2018-05-29 Richard Biener <rguenther@suse.de>
[official-gcc.git] / gcc / calls.c
blob35bcff7c6e579b0e890187756daa03f20fef69d9
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2018 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "backend.h"
24 #include "target.h"
25 #include "rtl.h"
26 #include "tree.h"
27 #include "gimple.h"
28 #include "predict.h"
29 #include "memmodel.h"
30 #include "tm_p.h"
31 #include "stringpool.h"
32 #include "expmed.h"
33 #include "optabs.h"
34 #include "emit-rtl.h"
35 #include "cgraph.h"
36 #include "diagnostic-core.h"
37 #include "fold-const.h"
38 #include "stor-layout.h"
39 #include "varasm.h"
40 #include "internal-fn.h"
41 #include "dojump.h"
42 #include "explow.h"
43 #include "calls.h"
44 #include "expr.h"
45 #include "output.h"
46 #include "langhooks.h"
47 #include "except.h"
48 #include "dbgcnt.h"
49 #include "rtl-iter.h"
50 #include "tree-chkp.h"
51 #include "tree-vrp.h"
52 #include "tree-ssanames.h"
53 #include "rtl-chkp.h"
54 #include "intl.h"
55 #include "stringpool.h"
56 #include "attribs.h"
57 #include "builtins.h"
58 #include "gimple-fold.h"
60 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
61 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
63 /* Data structure and subroutines used within expand_call. */
65 struct arg_data
67 /* Tree node for this argument. */
68 tree tree_value;
69 /* Mode for value; TYPE_MODE unless promoted. */
70 machine_mode mode;
71 /* Current RTL value for argument, or 0 if it isn't precomputed. */
72 rtx value;
73 /* Initially-compute RTL value for argument; only for const functions. */
74 rtx initial_value;
75 /* Register to pass this argument in, 0 if passed on stack, or an
76 PARALLEL if the arg is to be copied into multiple non-contiguous
77 registers. */
78 rtx reg;
79 /* Register to pass this argument in when generating tail call sequence.
80 This is not the same register as for normal calls on machines with
81 register windows. */
82 rtx tail_call_reg;
83 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
84 form for emit_group_move. */
85 rtx parallel_value;
86 /* If value is passed in neither reg nor stack, this field holds a number
87 of a special slot to be used. */
88 rtx special_slot;
89 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
90 there is no such pointer. */
91 int pointer_arg;
92 /* If pointer_arg refers a structure, then pointer_offset holds an offset
93 of a pointer in this structure. */
94 int pointer_offset;
95 /* If REG was promoted from the actual mode of the argument expression,
96 indicates whether the promotion is sign- or zero-extended. */
97 int unsignedp;
98 /* Number of bytes to put in registers. 0 means put the whole arg
99 in registers. Also 0 if not passed in registers. */
100 int partial;
101 /* Nonzero if argument must be passed on stack.
102 Note that some arguments may be passed on the stack
103 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
104 pass_on_stack identifies arguments that *cannot* go in registers. */
105 int pass_on_stack;
106 /* Some fields packaged up for locate_and_pad_parm. */
107 struct locate_and_pad_arg_data locate;
108 /* Location on the stack at which parameter should be stored. The store
109 has already been done if STACK == VALUE. */
110 rtx stack;
111 /* Location on the stack of the start of this argument slot. This can
112 differ from STACK if this arg pads downward. This location is known
113 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
114 rtx stack_slot;
115 /* Place that this stack area has been saved, if needed. */
116 rtx save_area;
117 /* If an argument's alignment does not permit direct copying into registers,
118 copy in smaller-sized pieces into pseudos. These are stored in a
119 block pointed to by this field. The next field says how many
120 word-sized pseudos we made. */
121 rtx *aligned_regs;
122 int n_aligned_regs;
125 /* A vector of one char per byte of stack space. A byte if nonzero if
126 the corresponding stack location has been used.
127 This vector is used to prevent a function call within an argument from
128 clobbering any stack already set up. */
129 static char *stack_usage_map;
131 /* Size of STACK_USAGE_MAP. */
132 static unsigned int highest_outgoing_arg_in_use;
134 /* Assume that any stack location at this byte index is used,
135 without checking the contents of stack_usage_map. */
136 static unsigned HOST_WIDE_INT stack_usage_watermark = HOST_WIDE_INT_M1U;
138 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
139 stack location's tail call argument has been already stored into the stack.
140 This bitmap is used to prevent sibling call optimization if function tries
141 to use parent's incoming argument slots when they have been already
142 overwritten with tail call arguments. */
143 static sbitmap stored_args_map;
145 /* Assume that any virtual-incoming location at this byte index has been
146 stored, without checking the contents of stored_args_map. */
147 static unsigned HOST_WIDE_INT stored_args_watermark;
149 /* stack_arg_under_construction is nonzero when an argument may be
150 initialized with a constructor call (including a C function that
151 returns a BLKmode struct) and expand_call must take special action
152 to make sure the object being constructed does not overlap the
153 argument list for the constructor call. */
154 static int stack_arg_under_construction;
156 static void precompute_register_parameters (int, struct arg_data *, int *);
157 static void store_bounds (struct arg_data *, struct arg_data *);
158 static int store_one_arg (struct arg_data *, rtx, int, int, int);
159 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
160 static int finalize_must_preallocate (int, int, struct arg_data *,
161 struct args_size *);
162 static void precompute_arguments (int, struct arg_data *);
163 static void compute_argument_addresses (struct arg_data *, rtx, int);
164 static rtx rtx_for_function_call (tree, tree);
165 static void load_register_parameters (struct arg_data *, int, rtx *, int,
166 int, int *);
167 static int special_function_p (const_tree, int);
168 static int check_sibcall_argument_overlap_1 (rtx);
169 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
171 static tree split_complex_types (tree);
173 #ifdef REG_PARM_STACK_SPACE
174 static rtx save_fixed_argument_area (int, rtx, int *, int *);
175 static void restore_fixed_argument_area (rtx, rtx, int, int);
176 #endif
178 /* Return true if bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
179 stack region might already be in use. */
181 static bool
182 stack_region_maybe_used_p (poly_uint64 lower_bound, poly_uint64 upper_bound,
183 unsigned int reg_parm_stack_space)
185 unsigned HOST_WIDE_INT const_lower, const_upper;
186 const_lower = constant_lower_bound (lower_bound);
187 if (!upper_bound.is_constant (&const_upper))
188 const_upper = HOST_WIDE_INT_M1U;
190 if (const_upper > stack_usage_watermark)
191 return true;
193 /* Don't worry about things in the fixed argument area;
194 it has already been saved. */
195 const_lower = MAX (const_lower, reg_parm_stack_space);
196 const_upper = MIN (const_upper, highest_outgoing_arg_in_use);
197 for (unsigned HOST_WIDE_INT i = const_lower; i < const_upper; ++i)
198 if (stack_usage_map[i])
199 return true;
200 return false;
203 /* Record that bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
204 stack region are now in use. */
206 static void
207 mark_stack_region_used (poly_uint64 lower_bound, poly_uint64 upper_bound)
209 unsigned HOST_WIDE_INT const_lower, const_upper;
210 const_lower = constant_lower_bound (lower_bound);
211 if (upper_bound.is_constant (&const_upper))
212 for (unsigned HOST_WIDE_INT i = const_lower; i < const_upper; ++i)
213 stack_usage_map[i] = 1;
214 else
215 stack_usage_watermark = MIN (stack_usage_watermark, const_lower);
218 /* Force FUNEXP into a form suitable for the address of a CALL,
219 and return that as an rtx. Also load the static chain register
220 if FNDECL is a nested function.
222 CALL_FUSAGE points to a variable holding the prospective
223 CALL_INSN_FUNCTION_USAGE information. */
226 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
227 rtx *call_fusage, int reg_parm_seen, int flags)
229 /* Make a valid memory address and copy constants through pseudo-regs,
230 but not for a constant address if -fno-function-cse. */
231 if (GET_CODE (funexp) != SYMBOL_REF)
233 /* If it's an indirect call by descriptor, generate code to perform
234 runtime identification of the pointer and load the descriptor. */
235 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
237 const int bit_val = targetm.calls.custom_function_descriptors;
238 rtx call_lab = gen_label_rtx ();
240 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
241 fndecl_or_type
242 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
243 fndecl_or_type);
244 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
245 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
247 if (GET_MODE (funexp) != Pmode)
248 funexp = convert_memory_address (Pmode, funexp);
250 /* Avoid long live ranges around function calls. */
251 funexp = copy_to_mode_reg (Pmode, funexp);
253 if (REG_P (chain))
254 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
256 /* Emit the runtime identification pattern. */
257 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
258 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
259 call_lab);
261 /* Statically predict the branch to very likely taken. */
262 rtx_insn *insn = get_last_insn ();
263 if (JUMP_P (insn))
264 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
266 /* Load the descriptor. */
267 rtx mem = gen_rtx_MEM (ptr_mode,
268 plus_constant (Pmode, funexp, - bit_val));
269 MEM_NOTRAP_P (mem) = 1;
270 mem = convert_memory_address (Pmode, mem);
271 emit_move_insn (chain, mem);
273 mem = gen_rtx_MEM (ptr_mode,
274 plus_constant (Pmode, funexp,
275 POINTER_SIZE / BITS_PER_UNIT
276 - bit_val));
277 MEM_NOTRAP_P (mem) = 1;
278 mem = convert_memory_address (Pmode, mem);
279 emit_move_insn (funexp, mem);
281 emit_label (call_lab);
283 if (REG_P (chain))
285 use_reg (call_fusage, chain);
286 STATIC_CHAIN_REG_P (chain) = 1;
289 /* Make sure we're not going to be overwritten below. */
290 gcc_assert (!static_chain_value);
293 /* If we are using registers for parameters, force the
294 function address into a register now. */
295 funexp = ((reg_parm_seen
296 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
297 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
298 : memory_address (FUNCTION_MODE, funexp));
300 else
302 /* funexp could be a SYMBOL_REF represents a function pointer which is
303 of ptr_mode. In this case, it should be converted into address mode
304 to be a valid address for memory rtx pattern. See PR 64971. */
305 if (GET_MODE (funexp) != Pmode)
306 funexp = convert_memory_address (Pmode, funexp);
308 if (!(flags & ECF_SIBCALL))
310 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
311 funexp = force_reg (Pmode, funexp);
315 if (static_chain_value != 0
316 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
317 || DECL_STATIC_CHAIN (fndecl_or_type)))
319 rtx chain;
321 chain = targetm.calls.static_chain (fndecl_or_type, false);
322 static_chain_value = convert_memory_address (Pmode, static_chain_value);
324 emit_move_insn (chain, static_chain_value);
325 if (REG_P (chain))
327 use_reg (call_fusage, chain);
328 STATIC_CHAIN_REG_P (chain) = 1;
332 return funexp;
335 /* Generate instructions to call function FUNEXP,
336 and optionally pop the results.
337 The CALL_INSN is the first insn generated.
339 FNDECL is the declaration node of the function. This is given to the
340 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
341 its own args.
343 FUNTYPE is the data type of the function. This is given to the hook
344 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
345 own args. We used to allow an identifier for library functions, but
346 that doesn't work when the return type is an aggregate type and the
347 calling convention says that the pointer to this aggregate is to be
348 popped by the callee.
350 STACK_SIZE is the number of bytes of arguments on the stack,
351 ROUNDED_STACK_SIZE is that number rounded up to
352 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
353 both to put into the call insn and to generate explicit popping
354 code if necessary.
356 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
357 It is zero if this call doesn't want a structure value.
359 NEXT_ARG_REG is the rtx that results from executing
360 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
361 just after all the args have had their registers assigned.
362 This could be whatever you like, but normally it is the first
363 arg-register beyond those used for args in this call,
364 or 0 if all the arg-registers are used in this call.
365 It is passed on to `gen_call' so you can put this info in the call insn.
367 VALREG is a hard register in which a value is returned,
368 or 0 if the call does not return a value.
370 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
371 the args to this call were processed.
372 We restore `inhibit_defer_pop' to that value.
374 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
375 denote registers used by the called function. */
377 static void
378 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
379 tree funtype ATTRIBUTE_UNUSED,
380 poly_int64 stack_size ATTRIBUTE_UNUSED,
381 poly_int64 rounded_stack_size,
382 poly_int64 struct_value_size ATTRIBUTE_UNUSED,
383 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
384 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
385 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
387 rtx rounded_stack_size_rtx = gen_int_mode (rounded_stack_size, Pmode);
388 rtx call, funmem, pat;
389 int already_popped = 0;
390 poly_int64 n_popped = 0;
392 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
393 patterns exist). Any popping that the callee does on return will
394 be from our caller's frame rather than ours. */
395 if (!(ecf_flags & ECF_SIBCALL))
397 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
399 #ifdef CALL_POPS_ARGS
400 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
401 #endif
404 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
405 and we don't want to load it into a register as an optimization,
406 because prepare_call_address already did it if it should be done. */
407 if (GET_CODE (funexp) != SYMBOL_REF)
408 funexp = memory_address (FUNCTION_MODE, funexp);
410 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
411 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
413 tree t = fndecl;
415 /* Although a built-in FUNCTION_DECL and its non-__builtin
416 counterpart compare equal and get a shared mem_attrs, they
417 produce different dump output in compare-debug compilations,
418 if an entry gets garbage collected in one compilation, then
419 adds a different (but equivalent) entry, while the other
420 doesn't run the garbage collector at the same spot and then
421 shares the mem_attr with the equivalent entry. */
422 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
424 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
425 if (t2)
426 t = t2;
429 set_mem_expr (funmem, t);
431 else if (fntree)
432 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
434 if (ecf_flags & ECF_SIBCALL)
436 if (valreg)
437 pat = targetm.gen_sibcall_value (valreg, funmem,
438 rounded_stack_size_rtx,
439 next_arg_reg, NULL_RTX);
440 else
441 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
442 next_arg_reg,
443 gen_int_mode (struct_value_size, Pmode));
445 /* If the target has "call" or "call_value" insns, then prefer them
446 if no arguments are actually popped. If the target does not have
447 "call" or "call_value" insns, then we must use the popping versions
448 even if the call has no arguments to pop. */
449 else if (maybe_ne (n_popped, 0)
450 || !(valreg
451 ? targetm.have_call_value ()
452 : targetm.have_call ()))
454 rtx n_pop = gen_int_mode (n_popped, Pmode);
456 /* If this subroutine pops its own args, record that in the call insn
457 if possible, for the sake of frame pointer elimination. */
459 if (valreg)
460 pat = targetm.gen_call_value_pop (valreg, funmem,
461 rounded_stack_size_rtx,
462 next_arg_reg, n_pop);
463 else
464 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
465 next_arg_reg, n_pop);
467 already_popped = 1;
469 else
471 if (valreg)
472 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
473 next_arg_reg, NULL_RTX);
474 else
475 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
476 gen_int_mode (struct_value_size, Pmode));
478 emit_insn (pat);
480 /* Find the call we just emitted. */
481 rtx_call_insn *call_insn = last_call_insn ();
483 /* Some target create a fresh MEM instead of reusing the one provided
484 above. Set its MEM_EXPR. */
485 call = get_call_rtx_from (call_insn);
486 if (call
487 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
488 && MEM_EXPR (funmem) != NULL_TREE)
489 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
491 /* Mark instrumented calls. */
492 if (call && fntree)
493 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
495 /* Put the register usage information there. */
496 add_function_usage_to (call_insn, call_fusage);
498 /* If this is a const call, then set the insn's unchanging bit. */
499 if (ecf_flags & ECF_CONST)
500 RTL_CONST_CALL_P (call_insn) = 1;
502 /* If this is a pure call, then set the insn's unchanging bit. */
503 if (ecf_flags & ECF_PURE)
504 RTL_PURE_CALL_P (call_insn) = 1;
506 /* If this is a const call, then set the insn's unchanging bit. */
507 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
508 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
510 /* Create a nothrow REG_EH_REGION note, if needed. */
511 make_reg_eh_region_note (call_insn, ecf_flags, 0);
513 if (ecf_flags & ECF_NORETURN)
514 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
516 if (ecf_flags & ECF_RETURNS_TWICE)
518 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
519 cfun->calls_setjmp = 1;
522 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
524 /* Restore this now, so that we do defer pops for this call's args
525 if the context of the call as a whole permits. */
526 inhibit_defer_pop = old_inhibit_defer_pop;
528 if (maybe_ne (n_popped, 0))
530 if (!already_popped)
531 CALL_INSN_FUNCTION_USAGE (call_insn)
532 = gen_rtx_EXPR_LIST (VOIDmode,
533 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
534 CALL_INSN_FUNCTION_USAGE (call_insn));
535 rounded_stack_size -= n_popped;
536 rounded_stack_size_rtx = gen_int_mode (rounded_stack_size, Pmode);
537 stack_pointer_delta -= n_popped;
539 add_args_size_note (call_insn, stack_pointer_delta);
541 /* If popup is needed, stack realign must use DRAP */
542 if (SUPPORTS_STACK_ALIGNMENT)
543 crtl->need_drap = true;
545 /* For noreturn calls when not accumulating outgoing args force
546 REG_ARGS_SIZE note to prevent crossjumping of calls with different
547 args sizes. */
548 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
549 add_args_size_note (call_insn, stack_pointer_delta);
551 if (!ACCUMULATE_OUTGOING_ARGS)
553 /* If returning from the subroutine does not automatically pop the args,
554 we need an instruction to pop them sooner or later.
555 Perhaps do it now; perhaps just record how much space to pop later.
557 If returning from the subroutine does pop the args, indicate that the
558 stack pointer will be changed. */
560 if (maybe_ne (rounded_stack_size, 0))
562 if (ecf_flags & ECF_NORETURN)
563 /* Just pretend we did the pop. */
564 stack_pointer_delta -= rounded_stack_size;
565 else if (flag_defer_pop && inhibit_defer_pop == 0
566 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
567 pending_stack_adjust += rounded_stack_size;
568 else
569 adjust_stack (rounded_stack_size_rtx);
572 /* When we accumulate outgoing args, we must avoid any stack manipulations.
573 Restore the stack pointer to its original value now. Usually
574 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
575 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
576 popping variants of functions exist as well.
578 ??? We may optimize similar to defer_pop above, but it is
579 probably not worthwhile.
581 ??? It will be worthwhile to enable combine_stack_adjustments even for
582 such machines. */
583 else if (maybe_ne (n_popped, 0))
584 anti_adjust_stack (gen_int_mode (n_popped, Pmode));
587 /* Determine if the function identified by FNDECL is one with
588 special properties we wish to know about. Modify FLAGS accordingly.
590 For example, if the function might return more than one time (setjmp), then
591 set ECF_RETURNS_TWICE.
593 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
594 space from the stack such as alloca. */
596 static int
597 special_function_p (const_tree fndecl, int flags)
599 tree name_decl = DECL_NAME (fndecl);
601 /* For instrumentation clones we want to derive flags
602 from the original name. */
603 if (cgraph_node::get (fndecl)
604 && cgraph_node::get (fndecl)->instrumentation_clone)
605 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
607 if (fndecl && name_decl
608 && IDENTIFIER_LENGTH (name_decl) <= 11
609 /* Exclude functions not at the file scope, or not `extern',
610 since they are not the magic functions we would otherwise
611 think they are.
612 FIXME: this should be handled with attributes, not with this
613 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
614 because you can declare fork() inside a function if you
615 wish. */
616 && (DECL_CONTEXT (fndecl) == NULL_TREE
617 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
618 && TREE_PUBLIC (fndecl))
620 const char *name = IDENTIFIER_POINTER (name_decl);
621 const char *tname = name;
623 /* We assume that alloca will always be called by name. It
624 makes no sense to pass it as a pointer-to-function to
625 anything that does not understand its behavior. */
626 if (IDENTIFIER_LENGTH (name_decl) == 6
627 && name[0] == 'a'
628 && ! strcmp (name, "alloca"))
629 flags |= ECF_MAY_BE_ALLOCA;
631 /* Disregard prefix _ or __. */
632 if (name[0] == '_')
634 if (name[1] == '_')
635 tname += 2;
636 else
637 tname += 1;
640 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
641 if (! strcmp (tname, "setjmp")
642 || ! strcmp (tname, "sigsetjmp")
643 || ! strcmp (name, "savectx")
644 || ! strcmp (name, "vfork")
645 || ! strcmp (name, "getcontext"))
646 flags |= ECF_RETURNS_TWICE;
649 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
650 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl)))
651 flags |= ECF_MAY_BE_ALLOCA;
653 return flags;
656 /* Similar to special_function_p; return a set of ERF_ flags for the
657 function FNDECL. */
658 static int
659 decl_return_flags (tree fndecl)
661 tree attr;
662 tree type = TREE_TYPE (fndecl);
663 if (!type)
664 return 0;
666 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
667 if (!attr)
668 return 0;
670 attr = TREE_VALUE (TREE_VALUE (attr));
671 if (!attr || TREE_STRING_LENGTH (attr) < 1)
672 return 0;
674 switch (TREE_STRING_POINTER (attr)[0])
676 case '1':
677 case '2':
678 case '3':
679 case '4':
680 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
682 case 'm':
683 return ERF_NOALIAS;
685 case '.':
686 default:
687 return 0;
691 /* Return nonzero when FNDECL represents a call to setjmp. */
694 setjmp_call_p (const_tree fndecl)
696 if (DECL_IS_RETURNS_TWICE (fndecl))
697 return ECF_RETURNS_TWICE;
698 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
702 /* Return true if STMT may be an alloca call. */
704 bool
705 gimple_maybe_alloca_call_p (const gimple *stmt)
707 tree fndecl;
709 if (!is_gimple_call (stmt))
710 return false;
712 fndecl = gimple_call_fndecl (stmt);
713 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
714 return true;
716 return false;
719 /* Return true if STMT is a builtin alloca call. */
721 bool
722 gimple_alloca_call_p (const gimple *stmt)
724 tree fndecl;
726 if (!is_gimple_call (stmt))
727 return false;
729 fndecl = gimple_call_fndecl (stmt);
730 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
731 switch (DECL_FUNCTION_CODE (fndecl))
733 CASE_BUILT_IN_ALLOCA:
734 return gimple_call_num_args (stmt) > 0;
735 default:
736 break;
739 return false;
742 /* Return true when exp contains a builtin alloca call. */
744 bool
745 alloca_call_p (const_tree exp)
747 tree fndecl;
748 if (TREE_CODE (exp) == CALL_EXPR
749 && (fndecl = get_callee_fndecl (exp))
750 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
751 switch (DECL_FUNCTION_CODE (fndecl))
753 CASE_BUILT_IN_ALLOCA:
754 return true;
755 default:
756 break;
759 return false;
762 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
763 function. Return FALSE otherwise. */
765 static bool
766 is_tm_builtin (const_tree fndecl)
768 if (fndecl == NULL)
769 return false;
771 if (decl_is_tm_clone (fndecl))
772 return true;
774 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
776 switch (DECL_FUNCTION_CODE (fndecl))
778 case BUILT_IN_TM_COMMIT:
779 case BUILT_IN_TM_COMMIT_EH:
780 case BUILT_IN_TM_ABORT:
781 case BUILT_IN_TM_IRREVOCABLE:
782 case BUILT_IN_TM_GETTMCLONE_IRR:
783 case BUILT_IN_TM_MEMCPY:
784 case BUILT_IN_TM_MEMMOVE:
785 case BUILT_IN_TM_MEMSET:
786 CASE_BUILT_IN_TM_STORE (1):
787 CASE_BUILT_IN_TM_STORE (2):
788 CASE_BUILT_IN_TM_STORE (4):
789 CASE_BUILT_IN_TM_STORE (8):
790 CASE_BUILT_IN_TM_STORE (FLOAT):
791 CASE_BUILT_IN_TM_STORE (DOUBLE):
792 CASE_BUILT_IN_TM_STORE (LDOUBLE):
793 CASE_BUILT_IN_TM_STORE (M64):
794 CASE_BUILT_IN_TM_STORE (M128):
795 CASE_BUILT_IN_TM_STORE (M256):
796 CASE_BUILT_IN_TM_LOAD (1):
797 CASE_BUILT_IN_TM_LOAD (2):
798 CASE_BUILT_IN_TM_LOAD (4):
799 CASE_BUILT_IN_TM_LOAD (8):
800 CASE_BUILT_IN_TM_LOAD (FLOAT):
801 CASE_BUILT_IN_TM_LOAD (DOUBLE):
802 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
803 CASE_BUILT_IN_TM_LOAD (M64):
804 CASE_BUILT_IN_TM_LOAD (M128):
805 CASE_BUILT_IN_TM_LOAD (M256):
806 case BUILT_IN_TM_LOG:
807 case BUILT_IN_TM_LOG_1:
808 case BUILT_IN_TM_LOG_2:
809 case BUILT_IN_TM_LOG_4:
810 case BUILT_IN_TM_LOG_8:
811 case BUILT_IN_TM_LOG_FLOAT:
812 case BUILT_IN_TM_LOG_DOUBLE:
813 case BUILT_IN_TM_LOG_LDOUBLE:
814 case BUILT_IN_TM_LOG_M64:
815 case BUILT_IN_TM_LOG_M128:
816 case BUILT_IN_TM_LOG_M256:
817 return true;
818 default:
819 break;
822 return false;
825 /* Detect flags (function attributes) from the function decl or type node. */
828 flags_from_decl_or_type (const_tree exp)
830 int flags = 0;
832 if (DECL_P (exp))
834 /* The function exp may have the `malloc' attribute. */
835 if (DECL_IS_MALLOC (exp))
836 flags |= ECF_MALLOC;
838 /* The function exp may have the `returns_twice' attribute. */
839 if (DECL_IS_RETURNS_TWICE (exp))
840 flags |= ECF_RETURNS_TWICE;
842 /* Process the pure and const attributes. */
843 if (TREE_READONLY (exp))
844 flags |= ECF_CONST;
845 if (DECL_PURE_P (exp))
846 flags |= ECF_PURE;
847 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
848 flags |= ECF_LOOPING_CONST_OR_PURE;
850 if (DECL_IS_NOVOPS (exp))
851 flags |= ECF_NOVOPS;
852 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
853 flags |= ECF_LEAF;
854 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
855 flags |= ECF_COLD;
857 if (TREE_NOTHROW (exp))
858 flags |= ECF_NOTHROW;
860 if (flag_tm)
862 if (is_tm_builtin (exp))
863 flags |= ECF_TM_BUILTIN;
864 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
865 || lookup_attribute ("transaction_pure",
866 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
867 flags |= ECF_TM_PURE;
870 flags = special_function_p (exp, flags);
872 else if (TYPE_P (exp))
874 if (TYPE_READONLY (exp))
875 flags |= ECF_CONST;
877 if (flag_tm
878 && ((flags & ECF_CONST) != 0
879 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
880 flags |= ECF_TM_PURE;
882 else
883 gcc_unreachable ();
885 if (TREE_THIS_VOLATILE (exp))
887 flags |= ECF_NORETURN;
888 if (flags & (ECF_CONST|ECF_PURE))
889 flags |= ECF_LOOPING_CONST_OR_PURE;
892 return flags;
895 /* Detect flags from a CALL_EXPR. */
898 call_expr_flags (const_tree t)
900 int flags;
901 tree decl = get_callee_fndecl (t);
903 if (decl)
904 flags = flags_from_decl_or_type (decl);
905 else if (CALL_EXPR_FN (t) == NULL_TREE)
906 flags = internal_fn_flags (CALL_EXPR_IFN (t));
907 else
909 tree type = TREE_TYPE (CALL_EXPR_FN (t));
910 if (type && TREE_CODE (type) == POINTER_TYPE)
911 flags = flags_from_decl_or_type (TREE_TYPE (type));
912 else
913 flags = 0;
914 if (CALL_EXPR_BY_DESCRIPTOR (t))
915 flags |= ECF_BY_DESCRIPTOR;
918 return flags;
921 /* Return true if TYPE should be passed by invisible reference. */
923 bool
924 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
925 tree type, bool named_arg)
927 if (type)
929 /* If this type contains non-trivial constructors, then it is
930 forbidden for the middle-end to create any new copies. */
931 if (TREE_ADDRESSABLE (type))
932 return true;
934 /* GCC post 3.4 passes *all* variable sized types by reference. */
935 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
936 return true;
938 /* If a record type should be passed the same as its first (and only)
939 member, use the type and mode of that member. */
940 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
942 type = TREE_TYPE (first_field (type));
943 mode = TYPE_MODE (type);
947 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
948 type, named_arg);
951 /* Return true if TYPE, which is passed by reference, should be callee
952 copied instead of caller copied. */
954 bool
955 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
956 tree type, bool named_arg)
958 if (type && TREE_ADDRESSABLE (type))
959 return false;
960 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
961 named_arg);
965 /* Precompute all register parameters as described by ARGS, storing values
966 into fields within the ARGS array.
968 NUM_ACTUALS indicates the total number elements in the ARGS array.
970 Set REG_PARM_SEEN if we encounter a register parameter. */
972 static void
973 precompute_register_parameters (int num_actuals, struct arg_data *args,
974 int *reg_parm_seen)
976 int i;
978 *reg_parm_seen = 0;
980 for (i = 0; i < num_actuals; i++)
981 if (args[i].reg != 0 && ! args[i].pass_on_stack)
983 *reg_parm_seen = 1;
985 if (args[i].value == 0)
987 push_temp_slots ();
988 args[i].value = expand_normal (args[i].tree_value);
989 preserve_temp_slots (args[i].value);
990 pop_temp_slots ();
993 /* If we are to promote the function arg to a wider mode,
994 do it now. */
996 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
997 args[i].value
998 = convert_modes (args[i].mode,
999 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1000 args[i].value, args[i].unsignedp);
1002 /* If the value is a non-legitimate constant, force it into a
1003 pseudo now. TLS symbols sometimes need a call to resolve. */
1004 if (CONSTANT_P (args[i].value)
1005 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
1006 args[i].value = force_reg (args[i].mode, args[i].value);
1008 /* If we're going to have to load the value by parts, pull the
1009 parts into pseudos. The part extraction process can involve
1010 non-trivial computation. */
1011 if (GET_CODE (args[i].reg) == PARALLEL)
1013 tree type = TREE_TYPE (args[i].tree_value);
1014 args[i].parallel_value
1015 = emit_group_load_into_temps (args[i].reg, args[i].value,
1016 type, int_size_in_bytes (type));
1019 /* If the value is expensive, and we are inside an appropriately
1020 short loop, put the value into a pseudo and then put the pseudo
1021 into the hard reg.
1023 For small register classes, also do this if this call uses
1024 register parameters. This is to avoid reload conflicts while
1025 loading the parameters registers. */
1027 else if ((! (REG_P (args[i].value)
1028 || (GET_CODE (args[i].value) == SUBREG
1029 && REG_P (SUBREG_REG (args[i].value)))))
1030 && args[i].mode != BLKmode
1031 && (set_src_cost (args[i].value, args[i].mode,
1032 optimize_insn_for_speed_p ())
1033 > COSTS_N_INSNS (1))
1034 && ((*reg_parm_seen
1035 && targetm.small_register_classes_for_mode_p (args[i].mode))
1036 || optimize))
1037 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1041 #ifdef REG_PARM_STACK_SPACE
1043 /* The argument list is the property of the called routine and it
1044 may clobber it. If the fixed area has been used for previous
1045 parameters, we must save and restore it. */
1047 static rtx
1048 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1050 unsigned int low;
1051 unsigned int high;
1053 /* Compute the boundary of the area that needs to be saved, if any. */
1054 high = reg_parm_stack_space;
1055 if (ARGS_GROW_DOWNWARD)
1056 high += 1;
1058 if (high > highest_outgoing_arg_in_use)
1059 high = highest_outgoing_arg_in_use;
1061 for (low = 0; low < high; low++)
1062 if (stack_usage_map[low] != 0 || low >= stack_usage_watermark)
1064 int num_to_save;
1065 machine_mode save_mode;
1066 int delta;
1067 rtx addr;
1068 rtx stack_area;
1069 rtx save_area;
1071 while (stack_usage_map[--high] == 0)
1074 *low_to_save = low;
1075 *high_to_save = high;
1077 num_to_save = high - low + 1;
1079 /* If we don't have the required alignment, must do this
1080 in BLKmode. */
1081 scalar_int_mode imode;
1082 if (int_mode_for_size (num_to_save * BITS_PER_UNIT, 1).exists (&imode)
1083 && (low & (MIN (GET_MODE_SIZE (imode),
1084 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)) == 0)
1085 save_mode = imode;
1086 else
1087 save_mode = BLKmode;
1089 if (ARGS_GROW_DOWNWARD)
1090 delta = -high;
1091 else
1092 delta = low;
1094 addr = plus_constant (Pmode, argblock, delta);
1095 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1097 set_mem_align (stack_area, PARM_BOUNDARY);
1098 if (save_mode == BLKmode)
1100 save_area = assign_stack_temp (BLKmode, num_to_save);
1101 emit_block_move (validize_mem (save_area), stack_area,
1102 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1104 else
1106 save_area = gen_reg_rtx (save_mode);
1107 emit_move_insn (save_area, stack_area);
1110 return save_area;
1113 return NULL_RTX;
1116 static void
1117 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1119 machine_mode save_mode = GET_MODE (save_area);
1120 int delta;
1121 rtx addr, stack_area;
1123 if (ARGS_GROW_DOWNWARD)
1124 delta = -high_to_save;
1125 else
1126 delta = low_to_save;
1128 addr = plus_constant (Pmode, argblock, delta);
1129 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1130 set_mem_align (stack_area, PARM_BOUNDARY);
1132 if (save_mode != BLKmode)
1133 emit_move_insn (stack_area, save_area);
1134 else
1135 emit_block_move (stack_area, validize_mem (save_area),
1136 GEN_INT (high_to_save - low_to_save + 1),
1137 BLOCK_OP_CALL_PARM);
1139 #endif /* REG_PARM_STACK_SPACE */
1141 /* If any elements in ARGS refer to parameters that are to be passed in
1142 registers, but not in memory, and whose alignment does not permit a
1143 direct copy into registers. Copy the values into a group of pseudos
1144 which we will later copy into the appropriate hard registers.
1146 Pseudos for each unaligned argument will be stored into the array
1147 args[argnum].aligned_regs. The caller is responsible for deallocating
1148 the aligned_regs array if it is nonzero. */
1150 static void
1151 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1153 int i, j;
1155 for (i = 0; i < num_actuals; i++)
1156 if (args[i].reg != 0 && ! args[i].pass_on_stack
1157 && GET_CODE (args[i].reg) != PARALLEL
1158 && args[i].mode == BLKmode
1159 && MEM_P (args[i].value)
1160 && (MEM_ALIGN (args[i].value)
1161 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1163 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1164 int endian_correction = 0;
1166 if (args[i].partial)
1168 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1169 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1171 else
1173 args[i].n_aligned_regs
1174 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1177 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1179 /* Structures smaller than a word are normally aligned to the
1180 least significant byte. On a BYTES_BIG_ENDIAN machine,
1181 this means we must skip the empty high order bytes when
1182 calculating the bit offset. */
1183 if (bytes < UNITS_PER_WORD
1184 #ifdef BLOCK_REG_PADDING
1185 && (BLOCK_REG_PADDING (args[i].mode,
1186 TREE_TYPE (args[i].tree_value), 1)
1187 == PAD_DOWNWARD)
1188 #else
1189 && BYTES_BIG_ENDIAN
1190 #endif
1192 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1194 for (j = 0; j < args[i].n_aligned_regs; j++)
1196 rtx reg = gen_reg_rtx (word_mode);
1197 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1198 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1200 args[i].aligned_regs[j] = reg;
1201 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1202 word_mode, word_mode, false, NULL);
1204 /* There is no need to restrict this code to loading items
1205 in TYPE_ALIGN sized hunks. The bitfield instructions can
1206 load up entire word sized registers efficiently.
1208 ??? This may not be needed anymore.
1209 We use to emit a clobber here but that doesn't let later
1210 passes optimize the instructions we emit. By storing 0 into
1211 the register later passes know the first AND to zero out the
1212 bitfield being set in the register is unnecessary. The store
1213 of 0 will be deleted as will at least the first AND. */
1215 emit_move_insn (reg, const0_rtx);
1217 bytes -= bitsize / BITS_PER_UNIT;
1218 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1219 word_mode, word, false);
1224 /* The limit set by -Walloc-larger-than=. */
1225 static GTY(()) tree alloc_object_size_limit;
1227 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1228 setting if the option is specified, or to the maximum object size if it
1229 is not. Return the initialized value. */
1231 static tree
1232 alloc_max_size (void)
1234 if (!alloc_object_size_limit)
1236 alloc_object_size_limit = max_object_size ();
1238 if (warn_alloc_size_limit)
1240 char *end = NULL;
1241 errno = 0;
1242 unsigned HOST_WIDE_INT unit = 1;
1243 unsigned HOST_WIDE_INT limit
1244 = strtoull (warn_alloc_size_limit, &end, 10);
1246 if (!errno)
1248 if (end && *end)
1250 /* Numeric option arguments are at most INT_MAX. Make it
1251 possible to specify a larger value by accepting common
1252 suffixes. */
1253 if (!strcmp (end, "kB"))
1254 unit = 1000;
1255 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1256 unit = 1024;
1257 else if (!strcmp (end, "MB"))
1258 unit = HOST_WIDE_INT_UC (1000) * 1000;
1259 else if (!strcasecmp (end, "MiB"))
1260 unit = HOST_WIDE_INT_UC (1024) * 1024;
1261 else if (!strcasecmp (end, "GB"))
1262 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000;
1263 else if (!strcasecmp (end, "GiB"))
1264 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024;
1265 else if (!strcasecmp (end, "TB"))
1266 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000;
1267 else if (!strcasecmp (end, "TiB"))
1268 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024;
1269 else if (!strcasecmp (end, "PB"))
1270 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000;
1271 else if (!strcasecmp (end, "PiB"))
1272 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024;
1273 else if (!strcasecmp (end, "EB"))
1274 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000
1275 * 1000;
1276 else if (!strcasecmp (end, "EiB"))
1277 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024
1278 * 1024;
1279 else
1280 unit = 0;
1283 if (unit)
1285 widest_int w = wi::mul (limit, unit);
1286 if (w < wi::to_widest (alloc_object_size_limit))
1287 alloc_object_size_limit
1288 = wide_int_to_tree (ptrdiff_type_node, w);
1293 return alloc_object_size_limit;
1296 /* Return true when EXP's range can be determined and set RANGE[] to it
1297 after adjusting it if necessary to make EXP a represents a valid size
1298 of object, or a valid size argument to an allocation function declared
1299 with attribute alloc_size (whose argument may be signed), or to a string
1300 manipulation function like memset. When ALLOW_ZERO is true, allow
1301 returning a range of [0, 0] for a size in an anti-range [1, N] where
1302 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1303 allocation functions like malloc but it is a valid argument to
1304 functions like memset. */
1306 bool
1307 get_size_range (tree exp, tree range[2], bool allow_zero /* = false */)
1309 if (tree_fits_uhwi_p (exp))
1311 /* EXP is a constant. */
1312 range[0] = range[1] = exp;
1313 return true;
1316 tree exptype = TREE_TYPE (exp);
1317 bool integral = INTEGRAL_TYPE_P (exptype);
1319 wide_int min, max;
1320 enum value_range_type range_type;
1322 if (TREE_CODE (exp) == SSA_NAME && integral)
1323 range_type = get_range_info (exp, &min, &max);
1324 else
1325 range_type = VR_VARYING;
1327 if (range_type == VR_VARYING)
1329 if (integral)
1331 /* Use the full range of the type of the expression when
1332 no value range information is available. */
1333 range[0] = TYPE_MIN_VALUE (exptype);
1334 range[1] = TYPE_MAX_VALUE (exptype);
1335 return true;
1338 range[0] = NULL_TREE;
1339 range[1] = NULL_TREE;
1340 return false;
1343 unsigned expprec = TYPE_PRECISION (exptype);
1345 bool signed_p = !TYPE_UNSIGNED (exptype);
1347 if (range_type == VR_ANTI_RANGE)
1349 if (signed_p)
1351 if (wi::les_p (max, 0))
1353 /* EXP is not in a strictly negative range. That means
1354 it must be in some (not necessarily strictly) positive
1355 range which includes zero. Since in signed to unsigned
1356 conversions negative values end up converted to large
1357 positive values, and otherwise they are not valid sizes,
1358 the resulting range is in both cases [0, TYPE_MAX]. */
1359 min = wi::zero (expprec);
1360 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1362 else if (wi::les_p (min - 1, 0))
1364 /* EXP is not in a negative-positive range. That means EXP
1365 is either negative, or greater than max. Since negative
1366 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1367 min = max + 1;
1368 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1370 else
1372 max = min - 1;
1373 min = wi::zero (expprec);
1376 else if (wi::eq_p (0, min - 1))
1378 /* EXP is unsigned and not in the range [1, MAX]. That means
1379 it's either zero or greater than MAX. Even though 0 would
1380 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1381 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1382 is greater than the limit the whole range is diagnosed. */
1383 if (allow_zero)
1384 min = max = wi::zero (expprec);
1385 else
1387 min = max + 1;
1388 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1391 else
1393 max = min - 1;
1394 min = wi::zero (expprec);
1398 range[0] = wide_int_to_tree (exptype, min);
1399 range[1] = wide_int_to_tree (exptype, max);
1401 return true;
1404 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1405 whose argument numbers given by IDX with values given by ARGS exceed
1406 the maximum object size or cause an unsigned oveflow (wrapping) when
1407 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1408 may be null for functions like malloc, and non-null for those like
1409 calloc that are decorated with a two-argument attribute alloc_size. */
1411 void
1412 maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1414 /* The range each of the (up to) two arguments is known to be in. */
1415 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1417 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1418 tree maxobjsize = alloc_max_size ();
1420 location_t loc = EXPR_LOCATION (exp);
1422 bool warned = false;
1424 /* Validate each argument individually. */
1425 for (unsigned i = 0; i != 2 && args[i]; ++i)
1427 if (TREE_CODE (args[i]) == INTEGER_CST)
1429 argrange[i][0] = args[i];
1430 argrange[i][1] = args[i];
1432 if (tree_int_cst_lt (args[i], integer_zero_node))
1434 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1435 "%Kargument %i value %qE is negative",
1436 exp, idx[i] + 1, args[i]);
1438 else if (integer_zerop (args[i]))
1440 /* Avoid issuing -Walloc-zero for allocation functions other
1441 than __builtin_alloca that are declared with attribute
1442 returns_nonnull because there's no portability risk. This
1443 avoids warning for such calls to libiberty's xmalloc and
1444 friends.
1445 Also avoid issuing the warning for calls to function named
1446 "alloca". */
1447 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1448 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1449 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1450 && !lookup_attribute ("returns_nonnull",
1451 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1452 warned = warning_at (loc, OPT_Walloc_zero,
1453 "%Kargument %i value is zero",
1454 exp, idx[i] + 1);
1456 else if (tree_int_cst_lt (maxobjsize, args[i]))
1458 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1459 mode and with -fno-exceptions as a way to indicate array
1460 size overflow. There's no good way to detect C++98 here
1461 so avoid diagnosing these calls for all C++ modes. */
1462 if (i == 0
1463 && !args[1]
1464 && lang_GNU_CXX ()
1465 && DECL_IS_OPERATOR_NEW (fn)
1466 && integer_all_onesp (args[i]))
1467 continue;
1469 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1470 "%Kargument %i value %qE exceeds "
1471 "maximum object size %E",
1472 exp, idx[i] + 1, args[i], maxobjsize);
1475 else if (TREE_CODE (args[i]) == SSA_NAME
1476 && get_size_range (args[i], argrange[i]))
1478 /* Verify that the argument's range is not negative (including
1479 upper bound of zero). */
1480 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1481 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1483 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1484 "%Kargument %i range [%E, %E] is negative",
1485 exp, idx[i] + 1,
1486 argrange[i][0], argrange[i][1]);
1488 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1490 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1491 "%Kargument %i range [%E, %E] exceeds "
1492 "maximum object size %E",
1493 exp, idx[i] + 1,
1494 argrange[i][0], argrange[i][1],
1495 maxobjsize);
1500 if (!argrange[0])
1501 return;
1503 /* For a two-argument alloc_size, validate the product of the two
1504 arguments if both of their values or ranges are known. */
1505 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1506 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1507 && !integer_onep (argrange[0][0])
1508 && !integer_onep (argrange[1][0]))
1510 /* Check for overflow in the product of a function decorated with
1511 attribute alloc_size (X, Y). */
1512 unsigned szprec = TYPE_PRECISION (size_type_node);
1513 wide_int x = wi::to_wide (argrange[0][0], szprec);
1514 wide_int y = wi::to_wide (argrange[1][0], szprec);
1516 bool vflow;
1517 wide_int prod = wi::umul (x, y, &vflow);
1519 if (vflow)
1520 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1521 "%Kproduct %<%E * %E%> of arguments %i and %i "
1522 "exceeds %<SIZE_MAX%>",
1523 exp, argrange[0][0], argrange[1][0],
1524 idx[0] + 1, idx[1] + 1);
1525 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1526 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1527 "%Kproduct %<%E * %E%> of arguments %i and %i "
1528 "exceeds maximum object size %E",
1529 exp, argrange[0][0], argrange[1][0],
1530 idx[0] + 1, idx[1] + 1,
1531 maxobjsize);
1533 if (warned)
1535 /* Print the full range of each of the two arguments to make
1536 it clear when it is, in fact, in a range and not constant. */
1537 if (argrange[0][0] != argrange [0][1])
1538 inform (loc, "argument %i in the range [%E, %E]",
1539 idx[0] + 1, argrange[0][0], argrange[0][1]);
1540 if (argrange[1][0] != argrange [1][1])
1541 inform (loc, "argument %i in the range [%E, %E]",
1542 idx[1] + 1, argrange[1][0], argrange[1][1]);
1546 if (warned)
1548 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1550 if (DECL_IS_BUILTIN (fn))
1551 inform (loc,
1552 "in a call to built-in allocation function %qD", fn);
1553 else
1554 inform (fnloc,
1555 "in a call to allocation function %qD declared here", fn);
1559 /* If EXPR refers to a character array or pointer declared attribute
1560 nonstring return a decl for that array or pointer and set *REF to
1561 the referenced enclosing object or pointer. Otherwise returns
1562 null. */
1564 tree
1565 get_attr_nonstring_decl (tree expr, tree *ref)
1567 tree decl = expr;
1568 if (TREE_CODE (decl) == SSA_NAME)
1570 gimple *def = SSA_NAME_DEF_STMT (decl);
1572 if (is_gimple_assign (def))
1574 tree_code code = gimple_assign_rhs_code (def);
1575 if (code == ADDR_EXPR
1576 || code == COMPONENT_REF
1577 || code == VAR_DECL)
1578 decl = gimple_assign_rhs1 (def);
1580 else if (tree var = SSA_NAME_VAR (decl))
1581 decl = var;
1584 if (TREE_CODE (decl) == ADDR_EXPR)
1585 decl = TREE_OPERAND (decl, 0);
1587 if (ref)
1588 *ref = decl;
1590 if (TREE_CODE (decl) == ARRAY_REF)
1591 decl = TREE_OPERAND (decl, 0);
1592 else if (TREE_CODE (decl) == COMPONENT_REF)
1593 decl = TREE_OPERAND (decl, 1);
1594 else if (TREE_CODE (decl) == MEM_REF)
1595 return get_attr_nonstring_decl (TREE_OPERAND (decl, 0), ref);
1597 if (DECL_P (decl)
1598 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl)))
1599 return decl;
1601 return NULL_TREE;
1604 /* Warn about passing a non-string array/pointer to a function that
1605 expects a nul-terminated string argument. */
1607 void
1608 maybe_warn_nonstring_arg (tree fndecl, tree exp)
1610 if (!fndecl || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
1611 return;
1613 bool with_bounds = CALL_WITH_BOUNDS_P (exp);
1615 unsigned nargs = call_expr_nargs (exp);
1617 /* The bound argument to a bounded string function like strncpy. */
1618 tree bound = NULL_TREE;
1620 /* The range of lengths of a string argument to one of the comparison
1621 functions. If the length is less than the bound it is used instead. */
1622 tree lenrng[2] = { NULL_TREE, NULL_TREE };
1624 /* It's safe to call "bounded" string functions with a non-string
1625 argument since the functions provide an explicit bound for this
1626 purpose. */
1627 switch (DECL_FUNCTION_CODE (fndecl))
1629 case BUILT_IN_STRCMP:
1630 case BUILT_IN_STRNCMP:
1631 case BUILT_IN_STRNCASECMP:
1633 /* For these, if one argument refers to one or more of a set
1634 of string constants or arrays of known size, determine
1635 the range of their known or possible lengths and use it
1636 conservatively as the bound for the unbounded function,
1637 and to adjust the range of the bound of the bounded ones. */
1638 unsigned stride = with_bounds ? 2 : 1;
1639 for (unsigned argno = 0; argno < nargs && !*lenrng; argno += stride)
1641 tree arg = CALL_EXPR_ARG (exp, argno);
1642 if (!get_attr_nonstring_decl (arg))
1643 get_range_strlen (arg, lenrng);
1646 /* Fall through. */
1648 case BUILT_IN_STPNCPY:
1649 case BUILT_IN_STPNCPY_CHK:
1650 case BUILT_IN_STRNCPY:
1651 case BUILT_IN_STRNCPY_CHK:
1653 unsigned argno = with_bounds ? 4 : 2;
1654 if (argno < nargs)
1655 bound = CALL_EXPR_ARG (exp, argno);
1656 break;
1659 case BUILT_IN_STRNDUP:
1661 unsigned argno = with_bounds ? 2 : 1;
1662 if (argno < nargs)
1663 bound = CALL_EXPR_ARG (exp, argno);
1664 break;
1667 default:
1668 break;
1671 /* Determine the range of the bound argument (if specified). */
1672 tree bndrng[2] = { NULL_TREE, NULL_TREE };
1673 if (bound)
1675 STRIP_NOPS (bound);
1676 get_size_range (bound, bndrng);
1679 if (*lenrng)
1681 /* Add one for the nul. */
1682 lenrng[0] = const_binop (PLUS_EXPR, TREE_TYPE (lenrng[0]),
1683 lenrng[0], size_one_node);
1684 lenrng[1] = const_binop (PLUS_EXPR, TREE_TYPE (lenrng[1]),
1685 lenrng[1], size_one_node);
1687 if (!bndrng[0])
1689 /* Conservatively use the upper bound of the lengths for
1690 both the lower and the upper bound of the operation. */
1691 bndrng[0] = lenrng[1];
1692 bndrng[1] = lenrng[1];
1693 bound = void_type_node;
1695 else
1697 /* Replace the bound on the operation with the upper bound
1698 of the length of the string if the latter is smaller. */
1699 if (tree_int_cst_lt (lenrng[1], bndrng[0]))
1700 bndrng[0] = lenrng[1];
1701 else if (tree_int_cst_lt (lenrng[1], bndrng[1]))
1702 bndrng[1] = lenrng[1];
1706 /* Iterate over the built-in function's formal arguments and check
1707 each const char* against the actual argument. If the actual
1708 argument is declared attribute non-string issue a warning unless
1709 the argument's maximum length is bounded. */
1710 function_args_iterator it;
1711 function_args_iter_init (&it, TREE_TYPE (fndecl));
1713 for (unsigned argno = 0; ; ++argno, function_args_iter_next (&it))
1715 /* Avoid iterating past the declared argument in a call
1716 to function declared without a prototype. */
1717 if (argno >= nargs)
1718 break;
1720 tree argtype = function_args_iter_cond (&it);
1721 if (!argtype)
1722 break;
1724 if (TREE_CODE (argtype) != POINTER_TYPE)
1725 continue;
1727 argtype = TREE_TYPE (argtype);
1729 if (TREE_CODE (argtype) != INTEGER_TYPE
1730 || !TYPE_READONLY (argtype))
1731 continue;
1733 argtype = TYPE_MAIN_VARIANT (argtype);
1734 if (argtype != char_type_node)
1735 continue;
1737 tree callarg = CALL_EXPR_ARG (exp, argno);
1738 if (TREE_CODE (callarg) == ADDR_EXPR)
1739 callarg = TREE_OPERAND (callarg, 0);
1741 /* See if the destination is declared with attribute "nonstring". */
1742 tree decl = get_attr_nonstring_decl (callarg);
1743 if (!decl)
1744 continue;
1746 tree type = TREE_TYPE (decl);
1748 /* The maximum number of array elements accessed. */
1749 offset_int wibnd = 0;
1750 if (bndrng[0])
1751 wibnd = wi::to_offset (bndrng[0]);
1753 /* Size of the array. */
1754 offset_int asize = wibnd;
1756 /* Determine the array size. For arrays of unknown bound and
1757 pointers reset BOUND to trigger the appropriate warning. */
1758 if (TREE_CODE (type) == ARRAY_TYPE)
1760 if (tree arrbnd = TYPE_DOMAIN (type))
1762 if ((arrbnd = TYPE_MAX_VALUE (arrbnd)))
1763 asize = wi::to_offset (arrbnd) + 1;
1765 else if (bound == void_type_node)
1766 bound = NULL_TREE;
1768 else if (bound == void_type_node)
1769 bound = NULL_TREE;
1771 location_t loc = EXPR_LOCATION (exp);
1773 bool warned = false;
1775 if (wi::ltu_p (asize, wibnd))
1776 warned = warning_at (loc, OPT_Wstringop_overflow_,
1777 "%qD argument %i declared attribute %<nonstring%> "
1778 "is smaller than the specified bound %E",
1779 fndecl, argno + 1, bndrng[0]);
1780 else if (!bound)
1781 warned = warning_at (loc, OPT_Wstringop_overflow_,
1782 "%qD argument %i declared attribute %<nonstring%>",
1783 fndecl, argno + 1);
1785 if (warned)
1786 inform (DECL_SOURCE_LOCATION (decl),
1787 "argument %qD declared here", decl);
1791 /* Issue an error if CALL_EXPR was flagged as requiring
1792 tall-call optimization. */
1794 static void
1795 maybe_complain_about_tail_call (tree call_expr, const char *reason)
1797 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1798 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1799 return;
1801 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1804 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1805 CALL_EXPR EXP.
1807 NUM_ACTUALS is the total number of parameters.
1809 N_NAMED_ARGS is the total number of named arguments.
1811 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1812 value, or null.
1814 FNDECL is the tree code for the target of this call (if known)
1816 ARGS_SO_FAR holds state needed by the target to know where to place
1817 the next argument.
1819 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1820 for arguments which are passed in registers.
1822 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1823 and may be modified by this routine.
1825 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1826 flags which may be modified by this routine.
1828 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1829 that requires allocation of stack space.
1831 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1832 the thunked-to function. */
1834 static void
1835 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1836 struct arg_data *args,
1837 struct args_size *args_size,
1838 int n_named_args ATTRIBUTE_UNUSED,
1839 tree exp, tree struct_value_addr_value,
1840 tree fndecl, tree fntype,
1841 cumulative_args_t args_so_far,
1842 int reg_parm_stack_space,
1843 rtx *old_stack_level,
1844 poly_int64_pod *old_pending_adj,
1845 int *must_preallocate, int *ecf_flags,
1846 bool *may_tailcall, bool call_from_thunk_p)
1848 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1849 location_t loc = EXPR_LOCATION (exp);
1851 /* Count arg position in order args appear. */
1852 int argpos;
1854 int i;
1856 args_size->constant = 0;
1857 args_size->var = 0;
1859 bitmap_obstack_initialize (NULL);
1861 /* In this loop, we consider args in the order they are written.
1862 We fill up ARGS from the back. */
1864 i = num_actuals - 1;
1866 int j = i, ptr_arg = -1;
1867 call_expr_arg_iterator iter;
1868 tree arg;
1869 bitmap slots = NULL;
1871 if (struct_value_addr_value)
1873 args[j].tree_value = struct_value_addr_value;
1874 j--;
1876 /* If we pass structure address then we need to
1877 create bounds for it. Since created bounds is
1878 a call statement, we expand it right here to avoid
1879 fixing all other places where it may be expanded. */
1880 if (CALL_WITH_BOUNDS_P (exp))
1882 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1883 args[j].tree_value
1884 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1885 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1886 EXPAND_NORMAL, 0, false);
1887 args[j].pointer_arg = j + 1;
1888 j--;
1891 argpos = 0;
1892 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1894 tree argtype = TREE_TYPE (arg);
1896 /* Remember last param with pointer and associate it
1897 with following pointer bounds. */
1898 if (CALL_WITH_BOUNDS_P (exp)
1899 && chkp_type_has_pointer (argtype))
1901 if (slots)
1902 BITMAP_FREE (slots);
1903 ptr_arg = j;
1904 if (!BOUNDED_TYPE_P (argtype))
1906 slots = BITMAP_ALLOC (NULL);
1907 chkp_find_bound_slots (argtype, slots);
1910 else if (CALL_WITH_BOUNDS_P (exp)
1911 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1912 argpos < n_named_args))
1914 if (slots)
1915 BITMAP_FREE (slots);
1916 ptr_arg = j;
1918 else if (POINTER_BOUNDS_TYPE_P (argtype))
1920 /* We expect bounds in instrumented calls only.
1921 Otherwise it is a sign we lost flag due to some optimization
1922 and may emit call args incorrectly. */
1923 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1925 /* For structures look for the next available pointer. */
1926 if (ptr_arg != -1 && slots)
1928 unsigned bnd_no = bitmap_first_set_bit (slots);
1929 args[j].pointer_offset =
1930 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1932 bitmap_clear_bit (slots, bnd_no);
1934 /* Check we have no more pointers in the structure. */
1935 if (bitmap_empty_p (slots))
1936 BITMAP_FREE (slots);
1938 args[j].pointer_arg = ptr_arg;
1940 /* Check we covered all pointers in the previous
1941 non bounds arg. */
1942 if (!slots)
1943 ptr_arg = -1;
1945 else
1946 ptr_arg = -1;
1948 if (targetm.calls.split_complex_arg
1949 && argtype
1950 && TREE_CODE (argtype) == COMPLEX_TYPE
1951 && targetm.calls.split_complex_arg (argtype))
1953 tree subtype = TREE_TYPE (argtype);
1954 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1955 j--;
1956 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1958 else
1959 args[j].tree_value = arg;
1960 j--;
1961 argpos++;
1964 if (slots)
1965 BITMAP_FREE (slots);
1968 bitmap_obstack_release (NULL);
1970 /* Extract attribute alloc_size and if set, store the indices of
1971 the corresponding arguments in ALLOC_IDX, and then the actual
1972 argument(s) at those indices in ALLOC_ARGS. */
1973 int alloc_idx[2] = { -1, -1 };
1974 if (tree alloc_size
1975 = (fndecl ? lookup_attribute ("alloc_size",
1976 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1977 : NULL_TREE))
1979 tree args = TREE_VALUE (alloc_size);
1980 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1981 if (TREE_CHAIN (args))
1982 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1985 /* Array for up to the two attribute alloc_size arguments. */
1986 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1988 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1989 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1991 tree type = TREE_TYPE (args[i].tree_value);
1992 int unsignedp;
1993 machine_mode mode;
1995 /* Replace erroneous argument with constant zero. */
1996 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1997 args[i].tree_value = integer_zero_node, type = integer_type_node;
1999 /* If TYPE is a transparent union or record, pass things the way
2000 we would pass the first field of the union or record. We have
2001 already verified that the modes are the same. */
2002 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
2003 && TYPE_TRANSPARENT_AGGR (type))
2004 type = TREE_TYPE (first_field (type));
2006 /* Decide where to pass this arg.
2008 args[i].reg is nonzero if all or part is passed in registers.
2010 args[i].partial is nonzero if part but not all is passed in registers,
2011 and the exact value says how many bytes are passed in registers.
2013 args[i].pass_on_stack is nonzero if the argument must at least be
2014 computed on the stack. It may then be loaded back into registers
2015 if args[i].reg is nonzero.
2017 These decisions are driven by the FUNCTION_... macros and must agree
2018 with those made by function.c. */
2020 /* See if this argument should be passed by invisible reference. */
2021 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
2022 type, argpos < n_named_args))
2024 bool callee_copies;
2025 tree base = NULL_TREE;
2027 callee_copies
2028 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
2029 type, argpos < n_named_args);
2031 /* If we're compiling a thunk, pass through invisible references
2032 instead of making a copy. */
2033 if (call_from_thunk_p
2034 || (callee_copies
2035 && !TREE_ADDRESSABLE (type)
2036 && (base = get_base_address (args[i].tree_value))
2037 && TREE_CODE (base) != SSA_NAME
2038 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
2040 /* We may have turned the parameter value into an SSA name.
2041 Go back to the original parameter so we can take the
2042 address. */
2043 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
2045 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
2046 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
2047 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
2049 /* Argument setup code may have copied the value to register. We
2050 revert that optimization now because the tail call code must
2051 use the original location. */
2052 if (TREE_CODE (args[i].tree_value) == PARM_DECL
2053 && !MEM_P (DECL_RTL (args[i].tree_value))
2054 && DECL_INCOMING_RTL (args[i].tree_value)
2055 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
2056 set_decl_rtl (args[i].tree_value,
2057 DECL_INCOMING_RTL (args[i].tree_value));
2059 mark_addressable (args[i].tree_value);
2061 /* We can't use sibcalls if a callee-copied argument is
2062 stored in the current function's frame. */
2063 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
2065 *may_tailcall = false;
2066 maybe_complain_about_tail_call (exp,
2067 "a callee-copied argument is"
2068 " stored in the current"
2069 " function's frame");
2072 args[i].tree_value = build_fold_addr_expr_loc (loc,
2073 args[i].tree_value);
2074 type = TREE_TYPE (args[i].tree_value);
2076 if (*ecf_flags & ECF_CONST)
2077 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
2079 else
2081 /* We make a copy of the object and pass the address to the
2082 function being called. */
2083 rtx copy;
2085 if (!COMPLETE_TYPE_P (type)
2086 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
2087 || (flag_stack_check == GENERIC_STACK_CHECK
2088 && compare_tree_int (TYPE_SIZE_UNIT (type),
2089 STACK_CHECK_MAX_VAR_SIZE) > 0))
2091 /* This is a variable-sized object. Make space on the stack
2092 for it. */
2093 rtx size_rtx = expr_size (args[i].tree_value);
2095 if (*old_stack_level == 0)
2097 emit_stack_save (SAVE_BLOCK, old_stack_level);
2098 *old_pending_adj = pending_stack_adjust;
2099 pending_stack_adjust = 0;
2102 /* We can pass TRUE as the 4th argument because we just
2103 saved the stack pointer and will restore it right after
2104 the call. */
2105 copy = allocate_dynamic_stack_space (size_rtx,
2106 TYPE_ALIGN (type),
2107 TYPE_ALIGN (type),
2108 max_int_size_in_bytes
2109 (type),
2110 true);
2111 copy = gen_rtx_MEM (BLKmode, copy);
2112 set_mem_attributes (copy, type, 1);
2114 else
2115 copy = assign_temp (type, 1, 0);
2117 store_expr (args[i].tree_value, copy, 0, false, false);
2119 /* Just change the const function to pure and then let
2120 the next test clear the pure based on
2121 callee_copies. */
2122 if (*ecf_flags & ECF_CONST)
2124 *ecf_flags &= ~ECF_CONST;
2125 *ecf_flags |= ECF_PURE;
2128 if (!callee_copies && *ecf_flags & ECF_PURE)
2129 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2131 args[i].tree_value
2132 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
2133 type = TREE_TYPE (args[i].tree_value);
2134 *may_tailcall = false;
2135 maybe_complain_about_tail_call (exp,
2136 "argument must be passed"
2137 " by copying");
2141 unsignedp = TYPE_UNSIGNED (type);
2142 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
2143 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
2145 args[i].unsignedp = unsignedp;
2146 args[i].mode = mode;
2148 targetm.calls.warn_parameter_passing_abi (args_so_far, type);
2150 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
2151 argpos < n_named_args);
2153 if (args[i].reg && CONST_INT_P (args[i].reg))
2155 args[i].special_slot = args[i].reg;
2156 args[i].reg = NULL;
2159 /* If this is a sibling call and the machine has register windows, the
2160 register window has to be unwinded before calling the routine, so
2161 arguments have to go into the incoming registers. */
2162 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
2163 args[i].tail_call_reg
2164 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
2165 argpos < n_named_args);
2166 else
2167 args[i].tail_call_reg = args[i].reg;
2169 if (args[i].reg)
2170 args[i].partial
2171 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
2172 argpos < n_named_args);
2174 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
2176 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2177 it means that we are to pass this arg in the register(s) designated
2178 by the PARALLEL, but also to pass it in the stack. */
2179 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
2180 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
2181 args[i].pass_on_stack = 1;
2183 /* If this is an addressable type, we must preallocate the stack
2184 since we must evaluate the object into its final location.
2186 If this is to be passed in both registers and the stack, it is simpler
2187 to preallocate. */
2188 if (TREE_ADDRESSABLE (type)
2189 || (args[i].pass_on_stack && args[i].reg != 0))
2190 *must_preallocate = 1;
2192 /* No stack allocation and padding for bounds. */
2193 if (POINTER_BOUNDS_P (args[i].tree_value))
2195 /* Compute the stack-size of this argument. */
2196 else if (args[i].reg == 0 || args[i].partial != 0
2197 || reg_parm_stack_space > 0
2198 || args[i].pass_on_stack)
2199 locate_and_pad_parm (mode, type,
2200 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2202 #else
2203 args[i].reg != 0,
2204 #endif
2205 reg_parm_stack_space,
2206 args[i].pass_on_stack ? 0 : args[i].partial,
2207 fndecl, args_size, &args[i].locate);
2208 #ifdef BLOCK_REG_PADDING
2209 else
2210 /* The argument is passed entirely in registers. See at which
2211 end it should be padded. */
2212 args[i].locate.where_pad =
2213 BLOCK_REG_PADDING (mode, type,
2214 int_size_in_bytes (type) <= UNITS_PER_WORD);
2215 #endif
2217 /* Update ARGS_SIZE, the total stack space for args so far. */
2219 args_size->constant += args[i].locate.size.constant;
2220 if (args[i].locate.size.var)
2221 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
2223 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2224 have been used, etc. */
2226 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
2227 type, argpos < n_named_args);
2229 /* Store argument values for functions decorated with attribute
2230 alloc_size. */
2231 if (argpos == alloc_idx[0])
2232 alloc_args[0] = args[i].tree_value;
2233 else if (argpos == alloc_idx[1])
2234 alloc_args[1] = args[i].tree_value;
2237 if (alloc_args[0])
2239 /* Check the arguments of functions decorated with attribute
2240 alloc_size. */
2241 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
2244 /* Detect passing non-string arguments to functions expecting
2245 nul-terminated strings. */
2246 maybe_warn_nonstring_arg (fndecl, exp);
2249 /* Update ARGS_SIZE to contain the total size for the argument block.
2250 Return the original constant component of the argument block's size.
2252 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2253 for arguments passed in registers. */
2255 static poly_int64
2256 compute_argument_block_size (int reg_parm_stack_space,
2257 struct args_size *args_size,
2258 tree fndecl ATTRIBUTE_UNUSED,
2259 tree fntype ATTRIBUTE_UNUSED,
2260 int preferred_stack_boundary ATTRIBUTE_UNUSED)
2262 poly_int64 unadjusted_args_size = args_size->constant;
2264 /* For accumulate outgoing args mode we don't need to align, since the frame
2265 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2266 backends from generating misaligned frame sizes. */
2267 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
2268 preferred_stack_boundary = STACK_BOUNDARY;
2270 /* Compute the actual size of the argument block required. The variable
2271 and constant sizes must be combined, the size may have to be rounded,
2272 and there may be a minimum required size. */
2274 if (args_size->var)
2276 args_size->var = ARGS_SIZE_TREE (*args_size);
2277 args_size->constant = 0;
2279 preferred_stack_boundary /= BITS_PER_UNIT;
2280 if (preferred_stack_boundary > 1)
2282 /* We don't handle this case yet. To handle it correctly we have
2283 to add the delta, round and subtract the delta.
2284 Currently no machine description requires this support. */
2285 gcc_assert (multiple_p (stack_pointer_delta,
2286 preferred_stack_boundary));
2287 args_size->var = round_up (args_size->var, preferred_stack_boundary);
2290 if (reg_parm_stack_space > 0)
2292 args_size->var
2293 = size_binop (MAX_EXPR, args_size->var,
2294 ssize_int (reg_parm_stack_space));
2296 /* The area corresponding to register parameters is not to count in
2297 the size of the block we need. So make the adjustment. */
2298 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2299 args_size->var
2300 = size_binop (MINUS_EXPR, args_size->var,
2301 ssize_int (reg_parm_stack_space));
2304 else
2306 preferred_stack_boundary /= BITS_PER_UNIT;
2307 if (preferred_stack_boundary < 1)
2308 preferred_stack_boundary = 1;
2309 args_size->constant = (aligned_upper_bound (args_size->constant
2310 + stack_pointer_delta,
2311 preferred_stack_boundary)
2312 - stack_pointer_delta);
2314 args_size->constant = upper_bound (args_size->constant,
2315 reg_parm_stack_space);
2317 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2318 args_size->constant -= reg_parm_stack_space;
2320 return unadjusted_args_size;
2323 /* Precompute parameters as needed for a function call.
2325 FLAGS is mask of ECF_* constants.
2327 NUM_ACTUALS is the number of arguments.
2329 ARGS is an array containing information for each argument; this
2330 routine fills in the INITIAL_VALUE and VALUE fields for each
2331 precomputed argument. */
2333 static void
2334 precompute_arguments (int num_actuals, struct arg_data *args)
2336 int i;
2338 /* If this is a libcall, then precompute all arguments so that we do not
2339 get extraneous instructions emitted as part of the libcall sequence. */
2341 /* If we preallocated the stack space, and some arguments must be passed
2342 on the stack, then we must precompute any parameter which contains a
2343 function call which will store arguments on the stack.
2344 Otherwise, evaluating the parameter may clobber previous parameters
2345 which have already been stored into the stack. (we have code to avoid
2346 such case by saving the outgoing stack arguments, but it results in
2347 worse code) */
2348 if (!ACCUMULATE_OUTGOING_ARGS)
2349 return;
2351 for (i = 0; i < num_actuals; i++)
2353 tree type;
2354 machine_mode mode;
2356 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2357 continue;
2359 /* If this is an addressable type, we cannot pre-evaluate it. */
2360 type = TREE_TYPE (args[i].tree_value);
2361 gcc_assert (!TREE_ADDRESSABLE (type));
2363 args[i].initial_value = args[i].value
2364 = expand_normal (args[i].tree_value);
2366 mode = TYPE_MODE (type);
2367 if (mode != args[i].mode)
2369 int unsignedp = args[i].unsignedp;
2370 args[i].value
2371 = convert_modes (args[i].mode, mode,
2372 args[i].value, args[i].unsignedp);
2374 /* CSE will replace this only if it contains args[i].value
2375 pseudo, so convert it down to the declared mode using
2376 a SUBREG. */
2377 if (REG_P (args[i].value)
2378 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2379 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2381 args[i].initial_value
2382 = gen_lowpart_SUBREG (mode, args[i].value);
2383 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2384 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2390 /* Given the current state of MUST_PREALLOCATE and information about
2391 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2392 compute and return the final value for MUST_PREALLOCATE. */
2394 static int
2395 finalize_must_preallocate (int must_preallocate, int num_actuals,
2396 struct arg_data *args, struct args_size *args_size)
2398 /* See if we have or want to preallocate stack space.
2400 If we would have to push a partially-in-regs parm
2401 before other stack parms, preallocate stack space instead.
2403 If the size of some parm is not a multiple of the required stack
2404 alignment, we must preallocate.
2406 If the total size of arguments that would otherwise create a copy in
2407 a temporary (such as a CALL) is more than half the total argument list
2408 size, preallocation is faster.
2410 Another reason to preallocate is if we have a machine (like the m88k)
2411 where stack alignment is required to be maintained between every
2412 pair of insns, not just when the call is made. However, we assume here
2413 that such machines either do not have push insns (and hence preallocation
2414 would occur anyway) or the problem is taken care of with
2415 PUSH_ROUNDING. */
2417 if (! must_preallocate)
2419 int partial_seen = 0;
2420 poly_int64 copy_to_evaluate_size = 0;
2421 int i;
2423 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2425 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2426 partial_seen = 1;
2427 else if (partial_seen && args[i].reg == 0)
2428 must_preallocate = 1;
2429 /* We preallocate in case there are bounds passed
2430 in the bounds table to have precomputed address
2431 for bounds association. */
2432 else if (POINTER_BOUNDS_P (args[i].tree_value)
2433 && !args[i].reg)
2434 must_preallocate = 1;
2436 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2437 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2438 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2439 || TREE_CODE (args[i].tree_value) == COND_EXPR
2440 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2441 copy_to_evaluate_size
2442 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2445 if (maybe_ne (args_size->constant, 0)
2446 && maybe_ge (copy_to_evaluate_size * 2, args_size->constant))
2447 must_preallocate = 1;
2449 return must_preallocate;
2452 /* If we preallocated stack space, compute the address of each argument
2453 and store it into the ARGS array.
2455 We need not ensure it is a valid memory address here; it will be
2456 validized when it is used.
2458 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2460 static void
2461 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2463 if (argblock)
2465 rtx arg_reg = argblock;
2466 int i;
2467 poly_int64 arg_offset = 0;
2469 if (GET_CODE (argblock) == PLUS)
2471 arg_reg = XEXP (argblock, 0);
2472 arg_offset = rtx_to_poly_int64 (XEXP (argblock, 1));
2475 for (i = 0; i < num_actuals; i++)
2477 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2478 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2479 rtx addr;
2480 unsigned int align, boundary;
2481 poly_uint64 units_on_stack = 0;
2482 machine_mode partial_mode = VOIDmode;
2484 /* Skip this parm if it will not be passed on the stack. */
2485 if (! args[i].pass_on_stack
2486 && args[i].reg != 0
2487 && args[i].partial == 0)
2488 continue;
2490 if (TYPE_EMPTY_P (TREE_TYPE (args[i].tree_value)))
2491 continue;
2493 /* Pointer Bounds are never passed on the stack. */
2494 if (POINTER_BOUNDS_P (args[i].tree_value))
2495 continue;
2497 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, offset);
2498 addr = plus_constant (Pmode, addr, arg_offset);
2500 if (args[i].partial != 0)
2502 /* Only part of the parameter is being passed on the stack.
2503 Generate a simple memory reference of the correct size. */
2504 units_on_stack = args[i].locate.size.constant;
2505 poly_uint64 bits_on_stack = units_on_stack * BITS_PER_UNIT;
2506 partial_mode = int_mode_for_size (bits_on_stack, 1).else_blk ();
2507 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2508 set_mem_size (args[i].stack, units_on_stack);
2510 else
2512 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2513 set_mem_attributes (args[i].stack,
2514 TREE_TYPE (args[i].tree_value), 1);
2516 align = BITS_PER_UNIT;
2517 boundary = args[i].locate.boundary;
2518 poly_int64 offset_val;
2519 if (args[i].locate.where_pad != PAD_DOWNWARD)
2520 align = boundary;
2521 else if (poly_int_rtx_p (offset, &offset_val))
2523 align = least_bit_hwi (boundary);
2524 unsigned int offset_align
2525 = known_alignment (offset_val) * BITS_PER_UNIT;
2526 if (offset_align != 0)
2527 align = MIN (align, offset_align);
2529 set_mem_align (args[i].stack, align);
2531 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, slot_offset);
2532 addr = plus_constant (Pmode, addr, arg_offset);
2534 if (args[i].partial != 0)
2536 /* Only part of the parameter is being passed on the stack.
2537 Generate a simple memory reference of the correct size.
2539 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2540 set_mem_size (args[i].stack_slot, units_on_stack);
2542 else
2544 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2545 set_mem_attributes (args[i].stack_slot,
2546 TREE_TYPE (args[i].tree_value), 1);
2548 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2550 /* Function incoming arguments may overlap with sibling call
2551 outgoing arguments and we cannot allow reordering of reads
2552 from function arguments with stores to outgoing arguments
2553 of sibling calls. */
2554 set_mem_alias_set (args[i].stack, 0);
2555 set_mem_alias_set (args[i].stack_slot, 0);
2560 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2561 in a call instruction.
2563 FNDECL is the tree node for the target function. For an indirect call
2564 FNDECL will be NULL_TREE.
2566 ADDR is the operand 0 of CALL_EXPR for this call. */
2568 static rtx
2569 rtx_for_function_call (tree fndecl, tree addr)
2571 rtx funexp;
2573 /* Get the function to call, in the form of RTL. */
2574 if (fndecl)
2576 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2577 TREE_USED (fndecl) = 1;
2579 /* Get a SYMBOL_REF rtx for the function address. */
2580 funexp = XEXP (DECL_RTL (fndecl), 0);
2582 else
2583 /* Generate an rtx (probably a pseudo-register) for the address. */
2585 push_temp_slots ();
2586 funexp = expand_normal (addr);
2587 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2589 return funexp;
2592 /* Return the static chain for this function, if any. */
2595 rtx_for_static_chain (const_tree fndecl_or_type, bool incoming_p)
2597 if (DECL_P (fndecl_or_type) && !DECL_STATIC_CHAIN (fndecl_or_type))
2598 return NULL;
2600 return targetm.calls.static_chain (fndecl_or_type, incoming_p);
2603 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2604 static struct
2606 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2607 or NULL_RTX if none has been scanned yet. */
2608 rtx_insn *scan_start;
2609 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2610 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2611 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2612 with fixed offset, or PC if this is with variable or unknown offset. */
2613 vec<rtx> cache;
2614 } internal_arg_pointer_exp_state;
2616 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2618 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2619 the tail call sequence, starting with first insn that hasn't been
2620 scanned yet, and note for each pseudo on the LHS whether it is based
2621 on crtl->args.internal_arg_pointer or not, and what offset from that
2622 that pointer it has. */
2624 static void
2625 internal_arg_pointer_based_exp_scan (void)
2627 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2629 if (scan_start == NULL_RTX)
2630 insn = get_insns ();
2631 else
2632 insn = NEXT_INSN (scan_start);
2634 while (insn)
2636 rtx set = single_set (insn);
2637 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2639 rtx val = NULL_RTX;
2640 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2641 /* Punt on pseudos set multiple times. */
2642 if (idx < internal_arg_pointer_exp_state.cache.length ()
2643 && (internal_arg_pointer_exp_state.cache[idx]
2644 != NULL_RTX))
2645 val = pc_rtx;
2646 else
2647 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2648 if (val != NULL_RTX)
2650 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2651 internal_arg_pointer_exp_state.cache
2652 .safe_grow_cleared (idx + 1);
2653 internal_arg_pointer_exp_state.cache[idx] = val;
2656 if (NEXT_INSN (insn) == NULL_RTX)
2657 scan_start = insn;
2658 insn = NEXT_INSN (insn);
2661 internal_arg_pointer_exp_state.scan_start = scan_start;
2664 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2665 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2666 it with fixed offset, or PC if this is with variable or unknown offset.
2667 TOPLEVEL is true if the function is invoked at the topmost level. */
2669 static rtx
2670 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2672 if (CONSTANT_P (rtl))
2673 return NULL_RTX;
2675 if (rtl == crtl->args.internal_arg_pointer)
2676 return const0_rtx;
2678 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2679 return NULL_RTX;
2681 poly_int64 offset;
2682 if (GET_CODE (rtl) == PLUS && poly_int_rtx_p (XEXP (rtl, 1), &offset))
2684 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2685 if (val == NULL_RTX || val == pc_rtx)
2686 return val;
2687 return plus_constant (Pmode, val, offset);
2690 /* When called at the topmost level, scan pseudo assignments in between the
2691 last scanned instruction in the tail call sequence and the latest insn
2692 in that sequence. */
2693 if (toplevel)
2694 internal_arg_pointer_based_exp_scan ();
2696 if (REG_P (rtl))
2698 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2699 if (idx < internal_arg_pointer_exp_state.cache.length ())
2700 return internal_arg_pointer_exp_state.cache[idx];
2702 return NULL_RTX;
2705 subrtx_iterator::array_type array;
2706 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2708 const_rtx x = *iter;
2709 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2710 return pc_rtx;
2711 if (MEM_P (x))
2712 iter.skip_subrtxes ();
2715 return NULL_RTX;
2718 /* Return true if SIZE bytes starting from address ADDR might overlap an
2719 already-clobbered argument area. This function is used to determine
2720 if we should give up a sibcall. */
2722 static bool
2723 mem_might_overlap_already_clobbered_arg_p (rtx addr, poly_uint64 size)
2725 poly_int64 i;
2726 unsigned HOST_WIDE_INT start, end;
2727 rtx val;
2729 if (bitmap_empty_p (stored_args_map)
2730 && stored_args_watermark == HOST_WIDE_INT_M1U)
2731 return false;
2732 val = internal_arg_pointer_based_exp (addr, true);
2733 if (val == NULL_RTX)
2734 return false;
2735 else if (!poly_int_rtx_p (val, &i))
2736 return true;
2738 if (known_eq (size, 0U))
2739 return false;
2741 if (STACK_GROWS_DOWNWARD)
2742 i -= crtl->args.pretend_args_size;
2743 else
2744 i += crtl->args.pretend_args_size;
2746 if (ARGS_GROW_DOWNWARD)
2747 i = -i - size;
2749 /* We can ignore any references to the function's pretend args,
2750 which at this point would manifest as negative values of I. */
2751 if (known_le (i, 0) && known_le (size, poly_uint64 (-i)))
2752 return false;
2754 start = maybe_lt (i, 0) ? 0 : constant_lower_bound (i);
2755 if (!(i + size).is_constant (&end))
2756 end = HOST_WIDE_INT_M1U;
2758 if (end > stored_args_watermark)
2759 return true;
2761 end = MIN (end, SBITMAP_SIZE (stored_args_map));
2762 for (unsigned HOST_WIDE_INT k = start; k < end; ++k)
2763 if (bitmap_bit_p (stored_args_map, k))
2764 return true;
2766 return false;
2769 /* Do the register loads required for any wholly-register parms or any
2770 parms which are passed both on the stack and in a register. Their
2771 expressions were already evaluated.
2773 Mark all register-parms as living through the call, putting these USE
2774 insns in the CALL_INSN_FUNCTION_USAGE field.
2776 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2777 checking, setting *SIBCALL_FAILURE if appropriate. */
2779 static void
2780 load_register_parameters (struct arg_data *args, int num_actuals,
2781 rtx *call_fusage, int flags, int is_sibcall,
2782 int *sibcall_failure)
2784 int i, j;
2786 for (i = 0; i < num_actuals; i++)
2788 rtx reg = ((flags & ECF_SIBCALL)
2789 ? args[i].tail_call_reg : args[i].reg);
2790 if (reg)
2792 int partial = args[i].partial;
2793 int nregs;
2794 poly_int64 size = 0;
2795 HOST_WIDE_INT const_size = 0;
2796 rtx_insn *before_arg = get_last_insn ();
2797 /* Set non-negative if we must move a word at a time, even if
2798 just one word (e.g, partial == 4 && mode == DFmode). Set
2799 to -1 if we just use a normal move insn. This value can be
2800 zero if the argument is a zero size structure. */
2801 nregs = -1;
2802 if (GET_CODE (reg) == PARALLEL)
2804 else if (partial)
2806 gcc_assert (partial % UNITS_PER_WORD == 0);
2807 nregs = partial / UNITS_PER_WORD;
2809 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2811 /* Variable-sized parameters should be described by a
2812 PARALLEL instead. */
2813 const_size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2814 gcc_assert (const_size >= 0);
2815 nregs = (const_size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2816 size = const_size;
2818 else
2819 size = GET_MODE_SIZE (args[i].mode);
2821 /* Handle calls that pass values in multiple non-contiguous
2822 locations. The Irix 6 ABI has examples of this. */
2824 if (GET_CODE (reg) == PARALLEL)
2825 emit_group_move (reg, args[i].parallel_value);
2827 /* If simple case, just do move. If normal partial, store_one_arg
2828 has already loaded the register for us. In all other cases,
2829 load the register(s) from memory. */
2831 else if (nregs == -1)
2833 emit_move_insn (reg, args[i].value);
2834 #ifdef BLOCK_REG_PADDING
2835 /* Handle case where we have a value that needs shifting
2836 up to the msb. eg. a QImode value and we're padding
2837 upward on a BYTES_BIG_ENDIAN machine. */
2838 if (args[i].locate.where_pad
2839 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD))
2841 gcc_checking_assert (ordered_p (size, UNITS_PER_WORD));
2842 if (maybe_lt (size, UNITS_PER_WORD))
2844 rtx x;
2845 poly_int64 shift
2846 = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2848 /* Assigning REG here rather than a temp makes
2849 CALL_FUSAGE report the whole reg as used.
2850 Strictly speaking, the call only uses SIZE
2851 bytes at the msb end, but it doesn't seem worth
2852 generating rtl to say that. */
2853 reg = gen_rtx_REG (word_mode, REGNO (reg));
2854 x = expand_shift (LSHIFT_EXPR, word_mode,
2855 reg, shift, reg, 1);
2856 if (x != reg)
2857 emit_move_insn (reg, x);
2860 #endif
2863 /* If we have pre-computed the values to put in the registers in
2864 the case of non-aligned structures, copy them in now. */
2866 else if (args[i].n_aligned_regs != 0)
2867 for (j = 0; j < args[i].n_aligned_regs; j++)
2868 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2869 args[i].aligned_regs[j]);
2871 else if (partial == 0 || args[i].pass_on_stack)
2873 /* SIZE and CONST_SIZE are 0 for partial arguments and
2874 the size of a BLKmode type otherwise. */
2875 gcc_checking_assert (known_eq (size, const_size));
2876 rtx mem = validize_mem (copy_rtx (args[i].value));
2878 /* Check for overlap with already clobbered argument area,
2879 providing that this has non-zero size. */
2880 if (is_sibcall
2881 && const_size != 0
2882 && (mem_might_overlap_already_clobbered_arg_p
2883 (XEXP (args[i].value, 0), const_size)))
2884 *sibcall_failure = 1;
2886 if (const_size % UNITS_PER_WORD == 0
2887 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2888 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2889 else
2891 if (nregs > 1)
2892 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2893 args[i].mode);
2894 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2895 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2896 unsigned int bitsize = const_size * BITS_PER_UNIT - bitoff;
2897 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2898 word_mode, word_mode, false,
2899 NULL);
2900 if (BYTES_BIG_ENDIAN)
2901 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2902 BITS_PER_WORD - bitsize, dest, 1);
2903 if (x != dest)
2904 emit_move_insn (dest, x);
2907 /* Handle a BLKmode that needs shifting. */
2908 if (nregs == 1 && const_size < UNITS_PER_WORD
2909 #ifdef BLOCK_REG_PADDING
2910 && args[i].locate.where_pad == PAD_DOWNWARD
2911 #else
2912 && BYTES_BIG_ENDIAN
2913 #endif
2916 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2917 int shift = (UNITS_PER_WORD - const_size) * BITS_PER_UNIT;
2918 enum tree_code dir = (BYTES_BIG_ENDIAN
2919 ? RSHIFT_EXPR : LSHIFT_EXPR);
2920 rtx x;
2922 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2923 if (x != dest)
2924 emit_move_insn (dest, x);
2928 /* When a parameter is a block, and perhaps in other cases, it is
2929 possible that it did a load from an argument slot that was
2930 already clobbered. */
2931 if (is_sibcall
2932 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2933 *sibcall_failure = 1;
2935 /* Handle calls that pass values in multiple non-contiguous
2936 locations. The Irix 6 ABI has examples of this. */
2937 if (GET_CODE (reg) == PARALLEL)
2938 use_group_regs (call_fusage, reg);
2939 else if (nregs == -1)
2940 use_reg_mode (call_fusage, reg,
2941 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2942 else if (nregs > 0)
2943 use_regs (call_fusage, REGNO (reg), nregs);
2948 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2949 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2950 bytes, then we would need to push some additional bytes to pad the
2951 arguments. So, we try to compute an adjust to the stack pointer for an
2952 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2953 bytes. Then, when the arguments are pushed the stack will be perfectly
2954 aligned.
2956 Return true if this optimization is possible, storing the adjustment
2957 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2958 bytes that should be popped after the call. */
2960 static bool
2961 combine_pending_stack_adjustment_and_call (poly_int64_pod *adjustment_out,
2962 poly_int64 unadjusted_args_size,
2963 struct args_size *args_size,
2964 unsigned int preferred_unit_stack_boundary)
2966 /* The number of bytes to pop so that the stack will be
2967 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2968 poly_int64 adjustment;
2969 /* The alignment of the stack after the arguments are pushed, if we
2970 just pushed the arguments without adjust the stack here. */
2971 unsigned HOST_WIDE_INT unadjusted_alignment;
2973 if (!known_misalignment (stack_pointer_delta + unadjusted_args_size,
2974 preferred_unit_stack_boundary,
2975 &unadjusted_alignment))
2976 return false;
2978 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2979 as possible -- leaving just enough left to cancel out the
2980 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2981 PENDING_STACK_ADJUST is non-negative, and congruent to
2982 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2984 /* Begin by trying to pop all the bytes. */
2985 unsigned HOST_WIDE_INT tmp_misalignment;
2986 if (!known_misalignment (pending_stack_adjust,
2987 preferred_unit_stack_boundary,
2988 &tmp_misalignment))
2989 return false;
2990 unadjusted_alignment -= tmp_misalignment;
2991 adjustment = pending_stack_adjust;
2992 /* Push enough additional bytes that the stack will be aligned
2993 after the arguments are pushed. */
2994 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2995 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2997 /* We need to know whether the adjusted argument size
2998 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2999 or a deallocation. */
3000 if (!ordered_p (adjustment, unadjusted_args_size))
3001 return false;
3003 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
3004 bytes after the call. The right number is the entire
3005 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
3006 by the arguments in the first place. */
3007 args_size->constant
3008 = pending_stack_adjust - adjustment + unadjusted_args_size;
3010 *adjustment_out = adjustment;
3011 return true;
3014 /* Scan X expression if it does not dereference any argument slots
3015 we already clobbered by tail call arguments (as noted in stored_args_map
3016 bitmap).
3017 Return nonzero if X expression dereferences such argument slots,
3018 zero otherwise. */
3020 static int
3021 check_sibcall_argument_overlap_1 (rtx x)
3023 RTX_CODE code;
3024 int i, j;
3025 const char *fmt;
3027 if (x == NULL_RTX)
3028 return 0;
3030 code = GET_CODE (x);
3032 /* We need not check the operands of the CALL expression itself. */
3033 if (code == CALL)
3034 return 0;
3036 if (code == MEM)
3037 return (mem_might_overlap_already_clobbered_arg_p
3038 (XEXP (x, 0), GET_MODE_SIZE (GET_MODE (x))));
3040 /* Scan all subexpressions. */
3041 fmt = GET_RTX_FORMAT (code);
3042 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3044 if (*fmt == 'e')
3046 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
3047 return 1;
3049 else if (*fmt == 'E')
3051 for (j = 0; j < XVECLEN (x, i); j++)
3052 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
3053 return 1;
3056 return 0;
3059 /* Scan sequence after INSN if it does not dereference any argument slots
3060 we already clobbered by tail call arguments (as noted in stored_args_map
3061 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
3062 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
3063 should be 0). Return nonzero if sequence after INSN dereferences such argument
3064 slots, zero otherwise. */
3066 static int
3067 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
3068 int mark_stored_args_map)
3070 poly_uint64 low, high;
3071 unsigned HOST_WIDE_INT const_low, const_high;
3073 if (insn == NULL_RTX)
3074 insn = get_insns ();
3075 else
3076 insn = NEXT_INSN (insn);
3078 for (; insn; insn = NEXT_INSN (insn))
3079 if (INSN_P (insn)
3080 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
3081 break;
3083 if (mark_stored_args_map)
3085 if (ARGS_GROW_DOWNWARD)
3086 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
3087 else
3088 low = arg->locate.slot_offset.constant;
3089 high = low + arg->locate.size.constant;
3091 const_low = constant_lower_bound (low);
3092 if (high.is_constant (&const_high))
3093 for (unsigned HOST_WIDE_INT i = const_low; i < const_high; ++i)
3094 bitmap_set_bit (stored_args_map, i);
3095 else
3096 stored_args_watermark = MIN (stored_args_watermark, const_low);
3098 return insn != NULL_RTX;
3101 /* Given that a function returns a value of mode MODE at the most
3102 significant end of hard register VALUE, shift VALUE left or right
3103 as specified by LEFT_P. Return true if some action was needed. */
3105 bool
3106 shift_return_value (machine_mode mode, bool left_p, rtx value)
3108 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
3109 machine_mode value_mode = GET_MODE (value);
3110 poly_int64 shift = GET_MODE_BITSIZE (value_mode) - GET_MODE_BITSIZE (mode);
3112 if (known_eq (shift, 0))
3113 return false;
3115 /* Use ashr rather than lshr for right shifts. This is for the benefit
3116 of the MIPS port, which requires SImode values to be sign-extended
3117 when stored in 64-bit registers. */
3118 if (!force_expand_binop (value_mode, left_p ? ashl_optab : ashr_optab,
3119 value, gen_int_shift_amount (value_mode, shift),
3120 value, 1, OPTAB_WIDEN))
3121 gcc_unreachable ();
3122 return true;
3125 /* If X is a likely-spilled register value, copy it to a pseudo
3126 register and return that register. Return X otherwise. */
3128 static rtx
3129 avoid_likely_spilled_reg (rtx x)
3131 rtx new_rtx;
3133 if (REG_P (x)
3134 && HARD_REGISTER_P (x)
3135 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
3137 /* Make sure that we generate a REG rather than a CONCAT.
3138 Moves into CONCATs can need nontrivial instructions,
3139 and the whole point of this function is to avoid
3140 using the hard register directly in such a situation. */
3141 generating_concat_p = 0;
3142 new_rtx = gen_reg_rtx (GET_MODE (x));
3143 generating_concat_p = 1;
3144 emit_move_insn (new_rtx, x);
3145 return new_rtx;
3147 return x;
3150 /* Helper function for expand_call.
3151 Return false is EXP is not implementable as a sibling call. */
3153 static bool
3154 can_implement_as_sibling_call_p (tree exp,
3155 rtx structure_value_addr,
3156 tree funtype,
3157 int reg_parm_stack_space ATTRIBUTE_UNUSED,
3158 tree fndecl,
3159 int flags,
3160 tree addr,
3161 const args_size &args_size)
3163 if (!targetm.have_sibcall_epilogue ())
3165 maybe_complain_about_tail_call
3166 (exp,
3167 "machine description does not have"
3168 " a sibcall_epilogue instruction pattern");
3169 return false;
3172 /* Doing sibling call optimization needs some work, since
3173 structure_value_addr can be allocated on the stack.
3174 It does not seem worth the effort since few optimizable
3175 sibling calls will return a structure. */
3176 if (structure_value_addr != NULL_RTX)
3178 maybe_complain_about_tail_call (exp, "callee returns a structure");
3179 return false;
3182 #ifdef REG_PARM_STACK_SPACE
3183 /* If outgoing reg parm stack space changes, we can not do sibcall. */
3184 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
3185 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
3186 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
3188 maybe_complain_about_tail_call (exp,
3189 "inconsistent size of stack space"
3190 " allocated for arguments which are"
3191 " passed in registers");
3192 return false;
3194 #endif
3196 /* Check whether the target is able to optimize the call
3197 into a sibcall. */
3198 if (!targetm.function_ok_for_sibcall (fndecl, exp))
3200 maybe_complain_about_tail_call (exp,
3201 "target is not able to optimize the"
3202 " call into a sibling call");
3203 return false;
3206 /* Functions that do not return exactly once may not be sibcall
3207 optimized. */
3208 if (flags & ECF_RETURNS_TWICE)
3210 maybe_complain_about_tail_call (exp, "callee returns twice");
3211 return false;
3213 if (flags & ECF_NORETURN)
3215 maybe_complain_about_tail_call (exp, "callee does not return");
3216 return false;
3219 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
3221 maybe_complain_about_tail_call (exp, "volatile function type");
3222 return false;
3225 /* If the called function is nested in the current one, it might access
3226 some of the caller's arguments, but could clobber them beforehand if
3227 the argument areas are shared. */
3228 if (fndecl && decl_function_context (fndecl) == current_function_decl)
3230 maybe_complain_about_tail_call (exp, "nested function");
3231 return false;
3234 /* If this function requires more stack slots than the current
3235 function, we cannot change it into a sibling call.
3236 crtl->args.pretend_args_size is not part of the
3237 stack allocated by our caller. */
3238 if (maybe_gt (args_size.constant,
3239 crtl->args.size - crtl->args.pretend_args_size))
3241 maybe_complain_about_tail_call (exp,
3242 "callee required more stack slots"
3243 " than the caller");
3244 return false;
3247 /* If the callee pops its own arguments, then it must pop exactly
3248 the same number of arguments as the current function. */
3249 if (maybe_ne (targetm.calls.return_pops_args (fndecl, funtype,
3250 args_size.constant),
3251 targetm.calls.return_pops_args (current_function_decl,
3252 TREE_TYPE
3253 (current_function_decl),
3254 crtl->args.size)))
3256 maybe_complain_about_tail_call (exp,
3257 "inconsistent number of"
3258 " popped arguments");
3259 return false;
3262 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
3264 maybe_complain_about_tail_call (exp, "frontend does not support"
3265 " sibling call");
3266 return false;
3269 /* All checks passed. */
3270 return true;
3273 /* Generate all the code for a CALL_EXPR exp
3274 and return an rtx for its value.
3275 Store the value in TARGET (specified as an rtx) if convenient.
3276 If the value is stored in TARGET then TARGET is returned.
3277 If IGNORE is nonzero, then we ignore the value of the function call. */
3280 expand_call (tree exp, rtx target, int ignore)
3282 /* Nonzero if we are currently expanding a call. */
3283 static int currently_expanding_call = 0;
3285 /* RTX for the function to be called. */
3286 rtx funexp;
3287 /* Sequence of insns to perform a normal "call". */
3288 rtx_insn *normal_call_insns = NULL;
3289 /* Sequence of insns to perform a tail "call". */
3290 rtx_insn *tail_call_insns = NULL;
3291 /* Data type of the function. */
3292 tree funtype;
3293 tree type_arg_types;
3294 tree rettype;
3295 /* Declaration of the function being called,
3296 or 0 if the function is computed (not known by name). */
3297 tree fndecl = 0;
3298 /* The type of the function being called. */
3299 tree fntype;
3300 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
3301 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
3302 int pass;
3304 /* Register in which non-BLKmode value will be returned,
3305 or 0 if no value or if value is BLKmode. */
3306 rtx valreg;
3307 /* Register(s) in which bounds are returned. */
3308 rtx valbnd = NULL;
3309 /* Address where we should return a BLKmode value;
3310 0 if value not BLKmode. */
3311 rtx structure_value_addr = 0;
3312 /* Nonzero if that address is being passed by treating it as
3313 an extra, implicit first parameter. Otherwise,
3314 it is passed by being copied directly into struct_value_rtx. */
3315 int structure_value_addr_parm = 0;
3316 /* Holds the value of implicit argument for the struct value. */
3317 tree structure_value_addr_value = NULL_TREE;
3318 /* Size of aggregate value wanted, or zero if none wanted
3319 or if we are using the non-reentrant PCC calling convention
3320 or expecting the value in registers. */
3321 poly_int64 struct_value_size = 0;
3322 /* Nonzero if called function returns an aggregate in memory PCC style,
3323 by returning the address of where to find it. */
3324 int pcc_struct_value = 0;
3325 rtx struct_value = 0;
3327 /* Number of actual parameters in this call, including struct value addr. */
3328 int num_actuals;
3329 /* Number of named args. Args after this are anonymous ones
3330 and they must all go on the stack. */
3331 int n_named_args;
3332 /* Number of complex actual arguments that need to be split. */
3333 int num_complex_actuals = 0;
3335 /* Vector of information about each argument.
3336 Arguments are numbered in the order they will be pushed,
3337 not the order they are written. */
3338 struct arg_data *args;
3340 /* Total size in bytes of all the stack-parms scanned so far. */
3341 struct args_size args_size;
3342 struct args_size adjusted_args_size;
3343 /* Size of arguments before any adjustments (such as rounding). */
3344 poly_int64 unadjusted_args_size;
3345 /* Data on reg parms scanned so far. */
3346 CUMULATIVE_ARGS args_so_far_v;
3347 cumulative_args_t args_so_far;
3348 /* Nonzero if a reg parm has been scanned. */
3349 int reg_parm_seen;
3350 /* Nonzero if this is an indirect function call. */
3352 /* Nonzero if we must avoid push-insns in the args for this call.
3353 If stack space is allocated for register parameters, but not by the
3354 caller, then it is preallocated in the fixed part of the stack frame.
3355 So the entire argument block must then be preallocated (i.e., we
3356 ignore PUSH_ROUNDING in that case). */
3358 int must_preallocate = !PUSH_ARGS;
3360 /* Size of the stack reserved for parameter registers. */
3361 int reg_parm_stack_space = 0;
3363 /* Address of space preallocated for stack parms
3364 (on machines that lack push insns), or 0 if space not preallocated. */
3365 rtx argblock = 0;
3367 /* Mask of ECF_ and ERF_ flags. */
3368 int flags = 0;
3369 int return_flags = 0;
3370 #ifdef REG_PARM_STACK_SPACE
3371 /* Define the boundary of the register parm stack space that needs to be
3372 saved, if any. */
3373 int low_to_save, high_to_save;
3374 rtx save_area = 0; /* Place that it is saved */
3375 #endif
3377 unsigned int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3378 char *initial_stack_usage_map = stack_usage_map;
3379 unsigned HOST_WIDE_INT initial_stack_usage_watermark = stack_usage_watermark;
3380 char *stack_usage_map_buf = NULL;
3382 poly_int64 old_stack_allocated;
3384 /* State variables to track stack modifications. */
3385 rtx old_stack_level = 0;
3386 int old_stack_arg_under_construction = 0;
3387 poly_int64 old_pending_adj = 0;
3388 int old_inhibit_defer_pop = inhibit_defer_pop;
3390 /* Some stack pointer alterations we make are performed via
3391 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3392 which we then also need to save/restore along the way. */
3393 poly_int64 old_stack_pointer_delta = 0;
3395 rtx call_fusage;
3396 tree addr = CALL_EXPR_FN (exp);
3397 int i;
3398 /* The alignment of the stack, in bits. */
3399 unsigned HOST_WIDE_INT preferred_stack_boundary;
3400 /* The alignment of the stack, in bytes. */
3401 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3402 /* The static chain value to use for this call. */
3403 rtx static_chain_value;
3404 /* See if this is "nothrow" function call. */
3405 if (TREE_NOTHROW (exp))
3406 flags |= ECF_NOTHROW;
3408 /* See if we can find a DECL-node for the actual function, and get the
3409 function attributes (flags) from the function decl or type node. */
3410 fndecl = get_callee_fndecl (exp);
3411 if (fndecl)
3413 fntype = TREE_TYPE (fndecl);
3414 flags |= flags_from_decl_or_type (fndecl);
3415 return_flags |= decl_return_flags (fndecl);
3417 else
3419 fntype = TREE_TYPE (TREE_TYPE (addr));
3420 flags |= flags_from_decl_or_type (fntype);
3421 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3422 flags |= ECF_BY_DESCRIPTOR;
3424 rettype = TREE_TYPE (exp);
3426 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3428 /* Warn if this value is an aggregate type,
3429 regardless of which calling convention we are using for it. */
3430 if (AGGREGATE_TYPE_P (rettype))
3431 warning (OPT_Waggregate_return, "function call has aggregate value");
3433 /* If the result of a non looping pure or const function call is
3434 ignored (or void), and none of its arguments are volatile, we can
3435 avoid expanding the call and just evaluate the arguments for
3436 side-effects. */
3437 if ((flags & (ECF_CONST | ECF_PURE))
3438 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3439 && (ignore || target == const0_rtx
3440 || TYPE_MODE (rettype) == VOIDmode))
3442 bool volatilep = false;
3443 tree arg;
3444 call_expr_arg_iterator iter;
3446 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3447 if (TREE_THIS_VOLATILE (arg))
3449 volatilep = true;
3450 break;
3453 if (! volatilep)
3455 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3456 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3457 return const0_rtx;
3461 #ifdef REG_PARM_STACK_SPACE
3462 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3463 #endif
3465 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3466 && reg_parm_stack_space > 0 && PUSH_ARGS)
3467 must_preallocate = 1;
3469 /* Set up a place to return a structure. */
3471 /* Cater to broken compilers. */
3472 if (aggregate_value_p (exp, fntype))
3474 /* This call returns a big structure. */
3475 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3477 #ifdef PCC_STATIC_STRUCT_RETURN
3479 pcc_struct_value = 1;
3481 #else /* not PCC_STATIC_STRUCT_RETURN */
3483 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype), &struct_value_size))
3484 struct_value_size = -1;
3486 /* Even if it is semantically safe to use the target as the return
3487 slot, it may be not sufficiently aligned for the return type. */
3488 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3489 && target
3490 && MEM_P (target)
3491 /* If rettype is addressable, we may not create a temporary.
3492 If target is properly aligned at runtime and the compiler
3493 just doesn't know about it, it will work fine, otherwise it
3494 will be UB. */
3495 && (TREE_ADDRESSABLE (rettype)
3496 || !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3497 && targetm.slow_unaligned_access (TYPE_MODE (rettype),
3498 MEM_ALIGN (target)))))
3499 structure_value_addr = XEXP (target, 0);
3500 else
3502 /* For variable-sized objects, we must be called with a target
3503 specified. If we were to allocate space on the stack here,
3504 we would have no way of knowing when to free it. */
3505 rtx d = assign_temp (rettype, 1, 1);
3506 structure_value_addr = XEXP (d, 0);
3507 target = 0;
3510 #endif /* not PCC_STATIC_STRUCT_RETURN */
3513 /* Figure out the amount to which the stack should be aligned. */
3514 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3515 if (fndecl)
3517 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3518 /* Without automatic stack alignment, we can't increase preferred
3519 stack boundary. With automatic stack alignment, it is
3520 unnecessary since unless we can guarantee that all callers will
3521 align the outgoing stack properly, callee has to align its
3522 stack anyway. */
3523 if (i
3524 && i->preferred_incoming_stack_boundary
3525 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3526 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3529 /* Operand 0 is a pointer-to-function; get the type of the function. */
3530 funtype = TREE_TYPE (addr);
3531 gcc_assert (POINTER_TYPE_P (funtype));
3532 funtype = TREE_TYPE (funtype);
3534 /* Count whether there are actual complex arguments that need to be split
3535 into their real and imaginary parts. Munge the type_arg_types
3536 appropriately here as well. */
3537 if (targetm.calls.split_complex_arg)
3539 call_expr_arg_iterator iter;
3540 tree arg;
3541 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3543 tree type = TREE_TYPE (arg);
3544 if (type && TREE_CODE (type) == COMPLEX_TYPE
3545 && targetm.calls.split_complex_arg (type))
3546 num_complex_actuals++;
3548 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3550 else
3551 type_arg_types = TYPE_ARG_TYPES (funtype);
3553 if (flags & ECF_MAY_BE_ALLOCA)
3554 cfun->calls_alloca = 1;
3556 /* If struct_value_rtx is 0, it means pass the address
3557 as if it were an extra parameter. Put the argument expression
3558 in structure_value_addr_value. */
3559 if (structure_value_addr && struct_value == 0)
3561 /* If structure_value_addr is a REG other than
3562 virtual_outgoing_args_rtx, we can use always use it. If it
3563 is not a REG, we must always copy it into a register.
3564 If it is virtual_outgoing_args_rtx, we must copy it to another
3565 register in some cases. */
3566 rtx temp = (!REG_P (structure_value_addr)
3567 || (ACCUMULATE_OUTGOING_ARGS
3568 && stack_arg_under_construction
3569 && structure_value_addr == virtual_outgoing_args_rtx)
3570 ? copy_addr_to_reg (convert_memory_address
3571 (Pmode, structure_value_addr))
3572 : structure_value_addr);
3574 structure_value_addr_value =
3575 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3576 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3579 /* Count the arguments and set NUM_ACTUALS. */
3580 num_actuals =
3581 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3583 /* Compute number of named args.
3584 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3586 if (type_arg_types != 0)
3587 n_named_args
3588 = (list_length (type_arg_types)
3589 /* Count the struct value address, if it is passed as a parm. */
3590 + structure_value_addr_parm);
3591 else
3592 /* If we know nothing, treat all args as named. */
3593 n_named_args = num_actuals;
3595 /* Start updating where the next arg would go.
3597 On some machines (such as the PA) indirect calls have a different
3598 calling convention than normal calls. The fourth argument in
3599 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3600 or not. */
3601 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3602 args_so_far = pack_cumulative_args (&args_so_far_v);
3604 /* Now possibly adjust the number of named args.
3605 Normally, don't include the last named arg if anonymous args follow.
3606 We do include the last named arg if
3607 targetm.calls.strict_argument_naming() returns nonzero.
3608 (If no anonymous args follow, the result of list_length is actually
3609 one too large. This is harmless.)
3611 If targetm.calls.pretend_outgoing_varargs_named() returns
3612 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3613 this machine will be able to place unnamed args that were passed
3614 in registers into the stack. So treat all args as named. This
3615 allows the insns emitting for a specific argument list to be
3616 independent of the function declaration.
3618 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3619 we do not have any reliable way to pass unnamed args in
3620 registers, so we must force them into memory. */
3622 if (type_arg_types != 0
3623 && targetm.calls.strict_argument_naming (args_so_far))
3625 else if (type_arg_types != 0
3626 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3627 /* Don't include the last named arg. */
3628 --n_named_args;
3629 else
3630 /* Treat all args as named. */
3631 n_named_args = num_actuals;
3633 /* Make a vector to hold all the information about each arg. */
3634 args = XCNEWVEC (struct arg_data, num_actuals);
3636 /* Build up entries in the ARGS array, compute the size of the
3637 arguments into ARGS_SIZE, etc. */
3638 initialize_argument_information (num_actuals, args, &args_size,
3639 n_named_args, exp,
3640 structure_value_addr_value, fndecl, fntype,
3641 args_so_far, reg_parm_stack_space,
3642 &old_stack_level, &old_pending_adj,
3643 &must_preallocate, &flags,
3644 &try_tail_call, CALL_FROM_THUNK_P (exp));
3646 if (args_size.var)
3647 must_preallocate = 1;
3649 /* Now make final decision about preallocating stack space. */
3650 must_preallocate = finalize_must_preallocate (must_preallocate,
3651 num_actuals, args,
3652 &args_size);
3654 /* If the structure value address will reference the stack pointer, we
3655 must stabilize it. We don't need to do this if we know that we are
3656 not going to adjust the stack pointer in processing this call. */
3658 if (structure_value_addr
3659 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3660 || reg_mentioned_p (virtual_outgoing_args_rtx,
3661 structure_value_addr))
3662 && (args_size.var
3663 || (!ACCUMULATE_OUTGOING_ARGS
3664 && maybe_ne (args_size.constant, 0))))
3665 structure_value_addr = copy_to_reg (structure_value_addr);
3667 /* Tail calls can make things harder to debug, and we've traditionally
3668 pushed these optimizations into -O2. Don't try if we're already
3669 expanding a call, as that means we're an argument. Don't try if
3670 there's cleanups, as we know there's code to follow the call. */
3672 if (currently_expanding_call++ != 0
3673 || !flag_optimize_sibling_calls
3674 || args_size.var
3675 || dbg_cnt (tail_call) == false)
3676 try_tail_call = 0;
3678 /* If the user has marked the function as requiring tail-call
3679 optimization, attempt it. */
3680 if (must_tail_call)
3681 try_tail_call = 1;
3683 /* Rest of purposes for tail call optimizations to fail. */
3684 if (try_tail_call)
3685 try_tail_call = can_implement_as_sibling_call_p (exp,
3686 structure_value_addr,
3687 funtype,
3688 reg_parm_stack_space,
3689 fndecl,
3690 flags, addr, args_size);
3692 /* Check if caller and callee disagree in promotion of function
3693 return value. */
3694 if (try_tail_call)
3696 machine_mode caller_mode, caller_promoted_mode;
3697 machine_mode callee_mode, callee_promoted_mode;
3698 int caller_unsignedp, callee_unsignedp;
3699 tree caller_res = DECL_RESULT (current_function_decl);
3701 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3702 caller_mode = DECL_MODE (caller_res);
3703 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3704 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3705 caller_promoted_mode
3706 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3707 &caller_unsignedp,
3708 TREE_TYPE (current_function_decl), 1);
3709 callee_promoted_mode
3710 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3711 &callee_unsignedp,
3712 funtype, 1);
3713 if (caller_mode != VOIDmode
3714 && (caller_promoted_mode != callee_promoted_mode
3715 || ((caller_mode != caller_promoted_mode
3716 || callee_mode != callee_promoted_mode)
3717 && (caller_unsignedp != callee_unsignedp
3718 || partial_subreg_p (caller_mode, callee_mode)))))
3720 try_tail_call = 0;
3721 maybe_complain_about_tail_call (exp,
3722 "caller and callee disagree in"
3723 " promotion of function"
3724 " return value");
3728 /* Ensure current function's preferred stack boundary is at least
3729 what we need. Stack alignment may also increase preferred stack
3730 boundary. */
3731 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3732 crtl->preferred_stack_boundary = preferred_stack_boundary;
3733 else
3734 preferred_stack_boundary = crtl->preferred_stack_boundary;
3736 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3738 /* We want to make two insn chains; one for a sibling call, the other
3739 for a normal call. We will select one of the two chains after
3740 initial RTL generation is complete. */
3741 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3743 int sibcall_failure = 0;
3744 /* We want to emit any pending stack adjustments before the tail
3745 recursion "call". That way we know any adjustment after the tail
3746 recursion call can be ignored if we indeed use the tail
3747 call expansion. */
3748 saved_pending_stack_adjust save;
3749 rtx_insn *insns, *before_call, *after_args;
3750 rtx next_arg_reg;
3752 if (pass == 0)
3754 /* State variables we need to save and restore between
3755 iterations. */
3756 save_pending_stack_adjust (&save);
3758 if (pass)
3759 flags &= ~ECF_SIBCALL;
3760 else
3761 flags |= ECF_SIBCALL;
3763 /* Other state variables that we must reinitialize each time
3764 through the loop (that are not initialized by the loop itself). */
3765 argblock = 0;
3766 call_fusage = 0;
3768 /* Start a new sequence for the normal call case.
3770 From this point on, if the sibling call fails, we want to set
3771 sibcall_failure instead of continuing the loop. */
3772 start_sequence ();
3774 /* Don't let pending stack adjusts add up to too much.
3775 Also, do all pending adjustments now if there is any chance
3776 this might be a call to alloca or if we are expanding a sibling
3777 call sequence.
3778 Also do the adjustments before a throwing call, otherwise
3779 exception handling can fail; PR 19225. */
3780 if (maybe_ge (pending_stack_adjust, 32)
3781 || (maybe_ne (pending_stack_adjust, 0)
3782 && (flags & ECF_MAY_BE_ALLOCA))
3783 || (maybe_ne (pending_stack_adjust, 0)
3784 && flag_exceptions && !(flags & ECF_NOTHROW))
3785 || pass == 0)
3786 do_pending_stack_adjust ();
3788 /* Precompute any arguments as needed. */
3789 if (pass)
3790 precompute_arguments (num_actuals, args);
3792 /* Now we are about to start emitting insns that can be deleted
3793 if a libcall is deleted. */
3794 if (pass && (flags & ECF_MALLOC))
3795 start_sequence ();
3797 if (pass == 0
3798 && crtl->stack_protect_guard
3799 && targetm.stack_protect_runtime_enabled_p ())
3800 stack_protect_epilogue ();
3802 adjusted_args_size = args_size;
3803 /* Compute the actual size of the argument block required. The variable
3804 and constant sizes must be combined, the size may have to be rounded,
3805 and there may be a minimum required size. When generating a sibcall
3806 pattern, do not round up, since we'll be re-using whatever space our
3807 caller provided. */
3808 unadjusted_args_size
3809 = compute_argument_block_size (reg_parm_stack_space,
3810 &adjusted_args_size,
3811 fndecl, fntype,
3812 (pass == 0 ? 0
3813 : preferred_stack_boundary));
3815 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3817 /* The argument block when performing a sibling call is the
3818 incoming argument block. */
3819 if (pass == 0)
3821 argblock = crtl->args.internal_arg_pointer;
3822 if (STACK_GROWS_DOWNWARD)
3823 argblock
3824 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3825 else
3826 argblock
3827 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3829 HOST_WIDE_INT map_size = constant_lower_bound (args_size.constant);
3830 stored_args_map = sbitmap_alloc (map_size);
3831 bitmap_clear (stored_args_map);
3832 stored_args_watermark = HOST_WIDE_INT_M1U;
3835 /* If we have no actual push instructions, or shouldn't use them,
3836 make space for all args right now. */
3837 else if (adjusted_args_size.var != 0)
3839 if (old_stack_level == 0)
3841 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3842 old_stack_pointer_delta = stack_pointer_delta;
3843 old_pending_adj = pending_stack_adjust;
3844 pending_stack_adjust = 0;
3845 /* stack_arg_under_construction says whether a stack arg is
3846 being constructed at the old stack level. Pushing the stack
3847 gets a clean outgoing argument block. */
3848 old_stack_arg_under_construction = stack_arg_under_construction;
3849 stack_arg_under_construction = 0;
3851 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3852 if (flag_stack_usage_info)
3853 current_function_has_unbounded_dynamic_stack_size = 1;
3855 else
3857 /* Note that we must go through the motions of allocating an argument
3858 block even if the size is zero because we may be storing args
3859 in the area reserved for register arguments, which may be part of
3860 the stack frame. */
3862 poly_int64 needed = adjusted_args_size.constant;
3864 /* Store the maximum argument space used. It will be pushed by
3865 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3866 checking). */
3868 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
3869 needed);
3871 if (must_preallocate)
3873 if (ACCUMULATE_OUTGOING_ARGS)
3875 /* Since the stack pointer will never be pushed, it is
3876 possible for the evaluation of a parm to clobber
3877 something we have already written to the stack.
3878 Since most function calls on RISC machines do not use
3879 the stack, this is uncommon, but must work correctly.
3881 Therefore, we save any area of the stack that was already
3882 written and that we are using. Here we set up to do this
3883 by making a new stack usage map from the old one. The
3884 actual save will be done by store_one_arg.
3886 Another approach might be to try to reorder the argument
3887 evaluations to avoid this conflicting stack usage. */
3889 /* Since we will be writing into the entire argument area,
3890 the map must be allocated for its entire size, not just
3891 the part that is the responsibility of the caller. */
3892 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3893 needed += reg_parm_stack_space;
3895 poly_int64 limit = needed;
3896 if (ARGS_GROW_DOWNWARD)
3897 limit += 1;
3899 /* For polynomial sizes, this is the maximum possible
3900 size needed for arguments with a constant size
3901 and offset. */
3902 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
3903 highest_outgoing_arg_in_use
3904 = MAX (initial_highest_arg_in_use, const_limit);
3906 free (stack_usage_map_buf);
3907 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3908 stack_usage_map = stack_usage_map_buf;
3910 if (initial_highest_arg_in_use)
3911 memcpy (stack_usage_map, initial_stack_usage_map,
3912 initial_highest_arg_in_use);
3914 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3915 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3916 (highest_outgoing_arg_in_use
3917 - initial_highest_arg_in_use));
3918 needed = 0;
3920 /* The address of the outgoing argument list must not be
3921 copied to a register here, because argblock would be left
3922 pointing to the wrong place after the call to
3923 allocate_dynamic_stack_space below. */
3925 argblock = virtual_outgoing_args_rtx;
3927 else
3929 /* Try to reuse some or all of the pending_stack_adjust
3930 to get this space. */
3931 if (inhibit_defer_pop == 0
3932 && (combine_pending_stack_adjustment_and_call
3933 (&needed,
3934 unadjusted_args_size,
3935 &adjusted_args_size,
3936 preferred_unit_stack_boundary)))
3938 /* combine_pending_stack_adjustment_and_call computes
3939 an adjustment before the arguments are allocated.
3940 Account for them and see whether or not the stack
3941 needs to go up or down. */
3942 needed = unadjusted_args_size - needed;
3944 /* Checked by
3945 combine_pending_stack_adjustment_and_call. */
3946 gcc_checking_assert (ordered_p (needed, 0));
3947 if (maybe_lt (needed, 0))
3949 /* We're releasing stack space. */
3950 /* ??? We can avoid any adjustment at all if we're
3951 already aligned. FIXME. */
3952 pending_stack_adjust = -needed;
3953 do_pending_stack_adjust ();
3954 needed = 0;
3956 else
3957 /* We need to allocate space. We'll do that in
3958 push_block below. */
3959 pending_stack_adjust = 0;
3962 /* Special case this because overhead of `push_block' in
3963 this case is non-trivial. */
3964 if (known_eq (needed, 0))
3965 argblock = virtual_outgoing_args_rtx;
3966 else
3968 rtx needed_rtx = gen_int_mode (needed, Pmode);
3969 argblock = push_block (needed_rtx, 0, 0);
3970 if (ARGS_GROW_DOWNWARD)
3971 argblock = plus_constant (Pmode, argblock, needed);
3974 /* We only really need to call `copy_to_reg' in the case
3975 where push insns are going to be used to pass ARGBLOCK
3976 to a function call in ARGS. In that case, the stack
3977 pointer changes value from the allocation point to the
3978 call point, and hence the value of
3979 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3980 as well always do it. */
3981 argblock = copy_to_reg (argblock);
3986 if (ACCUMULATE_OUTGOING_ARGS)
3988 /* The save/restore code in store_one_arg handles all
3989 cases except one: a constructor call (including a C
3990 function returning a BLKmode struct) to initialize
3991 an argument. */
3992 if (stack_arg_under_construction)
3994 rtx push_size
3995 = (gen_int_mode
3996 (adjusted_args_size.constant
3997 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl ? fntype
3998 : TREE_TYPE (fndecl))
3999 ? 0 : reg_parm_stack_space), Pmode));
4000 if (old_stack_level == 0)
4002 emit_stack_save (SAVE_BLOCK, &old_stack_level);
4003 old_stack_pointer_delta = stack_pointer_delta;
4004 old_pending_adj = pending_stack_adjust;
4005 pending_stack_adjust = 0;
4006 /* stack_arg_under_construction says whether a stack
4007 arg is being constructed at the old stack level.
4008 Pushing the stack gets a clean outgoing argument
4009 block. */
4010 old_stack_arg_under_construction
4011 = stack_arg_under_construction;
4012 stack_arg_under_construction = 0;
4013 /* Make a new map for the new argument list. */
4014 free (stack_usage_map_buf);
4015 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
4016 stack_usage_map = stack_usage_map_buf;
4017 highest_outgoing_arg_in_use = 0;
4018 stack_usage_watermark = HOST_WIDE_INT_M1U;
4020 /* We can pass TRUE as the 4th argument because we just
4021 saved the stack pointer and will restore it right after
4022 the call. */
4023 allocate_dynamic_stack_space (push_size, 0, BIGGEST_ALIGNMENT,
4024 -1, true);
4027 /* If argument evaluation might modify the stack pointer,
4028 copy the address of the argument list to a register. */
4029 for (i = 0; i < num_actuals; i++)
4030 if (args[i].pass_on_stack)
4032 argblock = copy_addr_to_reg (argblock);
4033 break;
4037 compute_argument_addresses (args, argblock, num_actuals);
4039 /* Stack is properly aligned, pops can't safely be deferred during
4040 the evaluation of the arguments. */
4041 NO_DEFER_POP;
4043 /* Precompute all register parameters. It isn't safe to compute
4044 anything once we have started filling any specific hard regs.
4045 TLS symbols sometimes need a call to resolve. Precompute
4046 register parameters before any stack pointer manipulation
4047 to avoid unaligned stack in the called function. */
4048 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
4050 OK_DEFER_POP;
4052 /* Perform stack alignment before the first push (the last arg). */
4053 if (argblock == 0
4054 && maybe_gt (adjusted_args_size.constant, reg_parm_stack_space)
4055 && maybe_ne (adjusted_args_size.constant, unadjusted_args_size))
4057 /* When the stack adjustment is pending, we get better code
4058 by combining the adjustments. */
4059 if (maybe_ne (pending_stack_adjust, 0)
4060 && ! inhibit_defer_pop
4061 && (combine_pending_stack_adjustment_and_call
4062 (&pending_stack_adjust,
4063 unadjusted_args_size,
4064 &adjusted_args_size,
4065 preferred_unit_stack_boundary)))
4066 do_pending_stack_adjust ();
4067 else if (argblock == 0)
4068 anti_adjust_stack (gen_int_mode (adjusted_args_size.constant
4069 - unadjusted_args_size,
4070 Pmode));
4072 /* Now that the stack is properly aligned, pops can't safely
4073 be deferred during the evaluation of the arguments. */
4074 NO_DEFER_POP;
4076 /* Record the maximum pushed stack space size. We need to delay
4077 doing it this far to take into account the optimization done
4078 by combine_pending_stack_adjustment_and_call. */
4079 if (flag_stack_usage_info
4080 && !ACCUMULATE_OUTGOING_ARGS
4081 && pass
4082 && adjusted_args_size.var == 0)
4084 poly_int64 pushed = (adjusted_args_size.constant
4085 + pending_stack_adjust);
4086 current_function_pushed_stack_size
4087 = upper_bound (current_function_pushed_stack_size, pushed);
4090 funexp = rtx_for_function_call (fndecl, addr);
4092 if (CALL_EXPR_STATIC_CHAIN (exp))
4093 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
4094 else
4095 static_chain_value = 0;
4097 #ifdef REG_PARM_STACK_SPACE
4098 /* Save the fixed argument area if it's part of the caller's frame and
4099 is clobbered by argument setup for this call. */
4100 if (ACCUMULATE_OUTGOING_ARGS && pass)
4101 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4102 &low_to_save, &high_to_save);
4103 #endif
4105 /* Now store (and compute if necessary) all non-register parms.
4106 These come before register parms, since they can require block-moves,
4107 which could clobber the registers used for register parms.
4108 Parms which have partial registers are not stored here,
4109 but we do preallocate space here if they want that. */
4111 for (i = 0; i < num_actuals; i++)
4113 /* Delay bounds until all other args are stored. */
4114 if (POINTER_BOUNDS_P (args[i].tree_value))
4115 continue;
4116 else if (args[i].reg == 0 || args[i].pass_on_stack)
4118 rtx_insn *before_arg = get_last_insn ();
4120 /* We don't allow passing huge (> 2^30 B) arguments
4121 by value. It would cause an overflow later on. */
4122 if (constant_lower_bound (adjusted_args_size.constant)
4123 >= (1 << (HOST_BITS_PER_INT - 2)))
4125 sorry ("passing too large argument on stack");
4126 continue;
4129 if (store_one_arg (&args[i], argblock, flags,
4130 adjusted_args_size.var != 0,
4131 reg_parm_stack_space)
4132 || (pass == 0
4133 && check_sibcall_argument_overlap (before_arg,
4134 &args[i], 1)))
4135 sibcall_failure = 1;
4138 if (args[i].stack)
4139 call_fusage
4140 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
4141 gen_rtx_USE (VOIDmode, args[i].stack),
4142 call_fusage);
4145 /* If we have a parm that is passed in registers but not in memory
4146 and whose alignment does not permit a direct copy into registers,
4147 make a group of pseudos that correspond to each register that we
4148 will later fill. */
4149 if (STRICT_ALIGNMENT)
4150 store_unaligned_arguments_into_pseudos (args, num_actuals);
4152 /* Now store any partially-in-registers parm.
4153 This is the last place a block-move can happen. */
4154 if (reg_parm_seen)
4155 for (i = 0; i < num_actuals; i++)
4156 if (args[i].partial != 0 && ! args[i].pass_on_stack)
4158 rtx_insn *before_arg = get_last_insn ();
4160 /* On targets with weird calling conventions (e.g. PA) it's
4161 hard to ensure that all cases of argument overlap between
4162 stack and registers work. Play it safe and bail out. */
4163 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
4165 sibcall_failure = 1;
4166 break;
4169 if (store_one_arg (&args[i], argblock, flags,
4170 adjusted_args_size.var != 0,
4171 reg_parm_stack_space)
4172 || (pass == 0
4173 && check_sibcall_argument_overlap (before_arg,
4174 &args[i], 1)))
4175 sibcall_failure = 1;
4178 bool any_regs = false;
4179 for (i = 0; i < num_actuals; i++)
4180 if (args[i].reg != NULL_RTX)
4182 any_regs = true;
4183 targetm.calls.call_args (args[i].reg, funtype);
4185 if (!any_regs)
4186 targetm.calls.call_args (pc_rtx, funtype);
4188 /* Figure out the register where the value, if any, will come back. */
4189 valreg = 0;
4190 valbnd = 0;
4191 if (TYPE_MODE (rettype) != VOIDmode
4192 && ! structure_value_addr)
4194 if (pcc_struct_value)
4196 valreg = hard_function_value (build_pointer_type (rettype),
4197 fndecl, NULL, (pass == 0));
4198 if (CALL_WITH_BOUNDS_P (exp))
4199 valbnd = targetm.calls.
4200 chkp_function_value_bounds (build_pointer_type (rettype),
4201 fndecl, (pass == 0));
4203 else
4205 valreg = hard_function_value (rettype, fndecl, fntype,
4206 (pass == 0));
4207 if (CALL_WITH_BOUNDS_P (exp))
4208 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
4209 fndecl,
4210 (pass == 0));
4213 /* If VALREG is a PARALLEL whose first member has a zero
4214 offset, use that. This is for targets such as m68k that
4215 return the same value in multiple places. */
4216 if (GET_CODE (valreg) == PARALLEL)
4218 rtx elem = XVECEXP (valreg, 0, 0);
4219 rtx where = XEXP (elem, 0);
4220 rtx offset = XEXP (elem, 1);
4221 if (offset == const0_rtx
4222 && GET_MODE (where) == GET_MODE (valreg))
4223 valreg = where;
4227 /* Store all bounds not passed in registers. */
4228 for (i = 0; i < num_actuals; i++)
4230 if (POINTER_BOUNDS_P (args[i].tree_value)
4231 && !args[i].reg)
4232 store_bounds (&args[i],
4233 args[i].pointer_arg == -1
4234 ? NULL
4235 : &args[args[i].pointer_arg]);
4238 /* If register arguments require space on the stack and stack space
4239 was not preallocated, allocate stack space here for arguments
4240 passed in registers. */
4241 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
4242 && !ACCUMULATE_OUTGOING_ARGS
4243 && must_preallocate == 0 && reg_parm_stack_space > 0)
4244 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
4246 /* Pass the function the address in which to return a
4247 structure value. */
4248 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
4250 structure_value_addr
4251 = convert_memory_address (Pmode, structure_value_addr);
4252 emit_move_insn (struct_value,
4253 force_reg (Pmode,
4254 force_operand (structure_value_addr,
4255 NULL_RTX)));
4257 if (REG_P (struct_value))
4258 use_reg (&call_fusage, struct_value);
4261 after_args = get_last_insn ();
4262 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
4263 static_chain_value, &call_fusage,
4264 reg_parm_seen, flags);
4266 load_register_parameters (args, num_actuals, &call_fusage, flags,
4267 pass == 0, &sibcall_failure);
4269 /* Save a pointer to the last insn before the call, so that we can
4270 later safely search backwards to find the CALL_INSN. */
4271 before_call = get_last_insn ();
4273 /* Set up next argument register. For sibling calls on machines
4274 with register windows this should be the incoming register. */
4275 if (pass == 0)
4276 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
4277 VOIDmode,
4278 void_type_node,
4279 true);
4280 else
4281 next_arg_reg = targetm.calls.function_arg (args_so_far,
4282 VOIDmode, void_type_node,
4283 true);
4285 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
4287 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
4288 arg_nr = num_actuals - arg_nr - 1;
4289 if (arg_nr >= 0
4290 && arg_nr < num_actuals
4291 && args[arg_nr].reg
4292 && valreg
4293 && REG_P (valreg)
4294 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
4295 call_fusage
4296 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
4297 gen_rtx_SET (valreg, args[arg_nr].reg),
4298 call_fusage);
4300 /* All arguments and registers used for the call must be set up by
4301 now! */
4303 /* Stack must be properly aligned now. */
4304 gcc_assert (!pass
4305 || multiple_p (stack_pointer_delta,
4306 preferred_unit_stack_boundary));
4308 /* Generate the actual call instruction. */
4309 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
4310 adjusted_args_size.constant, struct_value_size,
4311 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
4312 flags, args_so_far);
4314 if (flag_ipa_ra)
4316 rtx_call_insn *last;
4317 rtx datum = NULL_RTX;
4318 if (fndecl != NULL_TREE)
4320 datum = XEXP (DECL_RTL (fndecl), 0);
4321 gcc_assert (datum != NULL_RTX
4322 && GET_CODE (datum) == SYMBOL_REF);
4324 last = last_call_insn ();
4325 add_reg_note (last, REG_CALL_DECL, datum);
4328 /* If the call setup or the call itself overlaps with anything
4329 of the argument setup we probably clobbered our call address.
4330 In that case we can't do sibcalls. */
4331 if (pass == 0
4332 && check_sibcall_argument_overlap (after_args, 0, 0))
4333 sibcall_failure = 1;
4335 /* If a non-BLKmode value is returned at the most significant end
4336 of a register, shift the register right by the appropriate amount
4337 and update VALREG accordingly. BLKmode values are handled by the
4338 group load/store machinery below. */
4339 if (!structure_value_addr
4340 && !pcc_struct_value
4341 && TYPE_MODE (rettype) != VOIDmode
4342 && TYPE_MODE (rettype) != BLKmode
4343 && REG_P (valreg)
4344 && targetm.calls.return_in_msb (rettype))
4346 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
4347 sibcall_failure = 1;
4348 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
4351 if (pass && (flags & ECF_MALLOC))
4353 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4354 rtx_insn *last, *insns;
4356 /* The return value from a malloc-like function is a pointer. */
4357 if (TREE_CODE (rettype) == POINTER_TYPE)
4358 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
4360 emit_move_insn (temp, valreg);
4362 /* The return value from a malloc-like function can not alias
4363 anything else. */
4364 last = get_last_insn ();
4365 add_reg_note (last, REG_NOALIAS, temp);
4367 /* Write out the sequence. */
4368 insns = get_insns ();
4369 end_sequence ();
4370 emit_insn (insns);
4371 valreg = temp;
4374 /* For calls to `setjmp', etc., inform
4375 function.c:setjmp_warnings that it should complain if
4376 nonvolatile values are live. For functions that cannot
4377 return, inform flow that control does not fall through. */
4379 if ((flags & ECF_NORETURN) || pass == 0)
4381 /* The barrier must be emitted
4382 immediately after the CALL_INSN. Some ports emit more
4383 than just a CALL_INSN above, so we must search for it here. */
4385 rtx_insn *last = get_last_insn ();
4386 while (!CALL_P (last))
4388 last = PREV_INSN (last);
4389 /* There was no CALL_INSN? */
4390 gcc_assert (last != before_call);
4393 emit_barrier_after (last);
4395 /* Stack adjustments after a noreturn call are dead code.
4396 However when NO_DEFER_POP is in effect, we must preserve
4397 stack_pointer_delta. */
4398 if (inhibit_defer_pop == 0)
4400 stack_pointer_delta = old_stack_allocated;
4401 pending_stack_adjust = 0;
4405 /* If value type not void, return an rtx for the value. */
4407 if (TYPE_MODE (rettype) == VOIDmode
4408 || ignore)
4409 target = const0_rtx;
4410 else if (structure_value_addr)
4412 if (target == 0 || !MEM_P (target))
4414 target
4415 = gen_rtx_MEM (TYPE_MODE (rettype),
4416 memory_address (TYPE_MODE (rettype),
4417 structure_value_addr));
4418 set_mem_attributes (target, rettype, 1);
4421 else if (pcc_struct_value)
4423 /* This is the special C++ case where we need to
4424 know what the true target was. We take care to
4425 never use this value more than once in one expression. */
4426 target = gen_rtx_MEM (TYPE_MODE (rettype),
4427 copy_to_reg (valreg));
4428 set_mem_attributes (target, rettype, 1);
4430 /* Handle calls that return values in multiple non-contiguous locations.
4431 The Irix 6 ABI has examples of this. */
4432 else if (GET_CODE (valreg) == PARALLEL)
4434 if (target == 0)
4435 target = emit_group_move_into_temps (valreg);
4436 else if (rtx_equal_p (target, valreg))
4438 else if (GET_CODE (target) == PARALLEL)
4439 /* Handle the result of a emit_group_move_into_temps
4440 call in the previous pass. */
4441 emit_group_move (target, valreg);
4442 else
4443 emit_group_store (target, valreg, rettype,
4444 int_size_in_bytes (rettype));
4446 else if (target
4447 && GET_MODE (target) == TYPE_MODE (rettype)
4448 && GET_MODE (target) == GET_MODE (valreg))
4450 bool may_overlap = false;
4452 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4453 reg to a plain register. */
4454 if (!REG_P (target) || HARD_REGISTER_P (target))
4455 valreg = avoid_likely_spilled_reg (valreg);
4457 /* If TARGET is a MEM in the argument area, and we have
4458 saved part of the argument area, then we can't store
4459 directly into TARGET as it may get overwritten when we
4460 restore the argument save area below. Don't work too
4461 hard though and simply force TARGET to a register if it
4462 is a MEM; the optimizer is quite likely to sort it out. */
4463 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4464 for (i = 0; i < num_actuals; i++)
4465 if (args[i].save_area)
4467 may_overlap = true;
4468 break;
4471 if (may_overlap)
4472 target = copy_to_reg (valreg);
4473 else
4475 /* TARGET and VALREG cannot be equal at this point
4476 because the latter would not have
4477 REG_FUNCTION_VALUE_P true, while the former would if
4478 it were referring to the same register.
4480 If they refer to the same register, this move will be
4481 a no-op, except when function inlining is being
4482 done. */
4483 emit_move_insn (target, valreg);
4485 /* If we are setting a MEM, this code must be executed.
4486 Since it is emitted after the call insn, sibcall
4487 optimization cannot be performed in that case. */
4488 if (MEM_P (target))
4489 sibcall_failure = 1;
4492 else
4493 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4495 /* If we promoted this return value, make the proper SUBREG.
4496 TARGET might be const0_rtx here, so be careful. */
4497 if (REG_P (target)
4498 && TYPE_MODE (rettype) != BLKmode
4499 && GET_MODE (target) != TYPE_MODE (rettype))
4501 tree type = rettype;
4502 int unsignedp = TYPE_UNSIGNED (type);
4503 machine_mode pmode;
4505 /* Ensure we promote as expected, and get the new unsignedness. */
4506 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4507 funtype, 1);
4508 gcc_assert (GET_MODE (target) == pmode);
4510 poly_uint64 offset = subreg_lowpart_offset (TYPE_MODE (type),
4511 GET_MODE (target));
4512 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4513 SUBREG_PROMOTED_VAR_P (target) = 1;
4514 SUBREG_PROMOTED_SET (target, unsignedp);
4517 /* If size of args is variable or this was a constructor call for a stack
4518 argument, restore saved stack-pointer value. */
4520 if (old_stack_level)
4522 rtx_insn *prev = get_last_insn ();
4524 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4525 stack_pointer_delta = old_stack_pointer_delta;
4527 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4529 pending_stack_adjust = old_pending_adj;
4530 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4531 stack_arg_under_construction = old_stack_arg_under_construction;
4532 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4533 stack_usage_map = initial_stack_usage_map;
4534 stack_usage_watermark = initial_stack_usage_watermark;
4535 sibcall_failure = 1;
4537 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4539 #ifdef REG_PARM_STACK_SPACE
4540 if (save_area)
4541 restore_fixed_argument_area (save_area, argblock,
4542 high_to_save, low_to_save);
4543 #endif
4545 /* If we saved any argument areas, restore them. */
4546 for (i = 0; i < num_actuals; i++)
4547 if (args[i].save_area)
4549 machine_mode save_mode = GET_MODE (args[i].save_area);
4550 rtx stack_area
4551 = gen_rtx_MEM (save_mode,
4552 memory_address (save_mode,
4553 XEXP (args[i].stack_slot, 0)));
4555 if (save_mode != BLKmode)
4556 emit_move_insn (stack_area, args[i].save_area);
4557 else
4558 emit_block_move (stack_area, args[i].save_area,
4559 (gen_int_mode
4560 (args[i].locate.size.constant, Pmode)),
4561 BLOCK_OP_CALL_PARM);
4564 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4565 stack_usage_map = initial_stack_usage_map;
4566 stack_usage_watermark = initial_stack_usage_watermark;
4569 /* If this was alloca, record the new stack level. */
4570 if (flags & ECF_MAY_BE_ALLOCA)
4571 record_new_stack_level ();
4573 /* Free up storage we no longer need. */
4574 for (i = 0; i < num_actuals; ++i)
4575 free (args[i].aligned_regs);
4577 targetm.calls.end_call_args ();
4579 insns = get_insns ();
4580 end_sequence ();
4582 if (pass == 0)
4584 tail_call_insns = insns;
4586 /* Restore the pending stack adjustment now that we have
4587 finished generating the sibling call sequence. */
4589 restore_pending_stack_adjust (&save);
4591 /* Prepare arg structure for next iteration. */
4592 for (i = 0; i < num_actuals; i++)
4594 args[i].value = 0;
4595 args[i].aligned_regs = 0;
4596 args[i].stack = 0;
4599 sbitmap_free (stored_args_map);
4600 internal_arg_pointer_exp_state.scan_start = NULL;
4601 internal_arg_pointer_exp_state.cache.release ();
4603 else
4605 normal_call_insns = insns;
4607 /* Verify that we've deallocated all the stack we used. */
4608 gcc_assert ((flags & ECF_NORETURN)
4609 || known_eq (old_stack_allocated,
4610 stack_pointer_delta
4611 - pending_stack_adjust));
4614 /* If something prevents making this a sibling call,
4615 zero out the sequence. */
4616 if (sibcall_failure)
4617 tail_call_insns = NULL;
4618 else
4619 break;
4622 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4623 arguments too, as argument area is now clobbered by the call. */
4624 if (tail_call_insns)
4626 emit_insn (tail_call_insns);
4627 crtl->tail_call_emit = true;
4629 else
4631 emit_insn (normal_call_insns);
4632 if (try_tail_call)
4633 /* Ideally we'd emit a message for all of the ways that it could
4634 have failed. */
4635 maybe_complain_about_tail_call (exp, "tail call production failed");
4638 currently_expanding_call--;
4640 free (stack_usage_map_buf);
4641 free (args);
4643 /* Join result with returned bounds so caller may use them if needed. */
4644 target = chkp_join_splitted_slot (target, valbnd);
4646 return target;
4649 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4650 this function's incoming arguments.
4652 At the start of RTL generation we know the only REG_EQUIV notes
4653 in the rtl chain are those for incoming arguments, so we can look
4654 for REG_EQUIV notes between the start of the function and the
4655 NOTE_INSN_FUNCTION_BEG.
4657 This is (slight) overkill. We could keep track of the highest
4658 argument we clobber and be more selective in removing notes, but it
4659 does not seem to be worth the effort. */
4661 void
4662 fixup_tail_calls (void)
4664 rtx_insn *insn;
4666 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4668 rtx note;
4670 /* There are never REG_EQUIV notes for the incoming arguments
4671 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4672 if (NOTE_P (insn)
4673 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4674 break;
4676 note = find_reg_note (insn, REG_EQUIV, 0);
4677 if (note)
4678 remove_note (insn, note);
4679 note = find_reg_note (insn, REG_EQUIV, 0);
4680 gcc_assert (!note);
4684 /* Traverse a list of TYPES and expand all complex types into their
4685 components. */
4686 static tree
4687 split_complex_types (tree types)
4689 tree p;
4691 /* Before allocating memory, check for the common case of no complex. */
4692 for (p = types; p; p = TREE_CHAIN (p))
4694 tree type = TREE_VALUE (p);
4695 if (TREE_CODE (type) == COMPLEX_TYPE
4696 && targetm.calls.split_complex_arg (type))
4697 goto found;
4699 return types;
4701 found:
4702 types = copy_list (types);
4704 for (p = types; p; p = TREE_CHAIN (p))
4706 tree complex_type = TREE_VALUE (p);
4708 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4709 && targetm.calls.split_complex_arg (complex_type))
4711 tree next, imag;
4713 /* Rewrite complex type with component type. */
4714 TREE_VALUE (p) = TREE_TYPE (complex_type);
4715 next = TREE_CHAIN (p);
4717 /* Add another component type for the imaginary part. */
4718 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4719 TREE_CHAIN (p) = imag;
4720 TREE_CHAIN (imag) = next;
4722 /* Skip the newly created node. */
4723 p = TREE_CHAIN (p);
4727 return types;
4730 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4731 for a value of mode OUTMODE,
4732 with NARGS different arguments, passed as ARGS.
4733 Store the return value if RETVAL is nonzero: store it in VALUE if
4734 VALUE is nonnull, otherwise pick a convenient location. In either
4735 case return the location of the stored value.
4737 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4738 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4739 other types of library calls. */
4742 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4743 enum libcall_type fn_type,
4744 machine_mode outmode, int nargs, rtx_mode_t *args)
4746 /* Total size in bytes of all the stack-parms scanned so far. */
4747 struct args_size args_size;
4748 /* Size of arguments before any adjustments (such as rounding). */
4749 struct args_size original_args_size;
4750 int argnum;
4751 rtx fun;
4752 /* Todo, choose the correct decl type of orgfun. Sadly this information
4753 isn't present here, so we default to native calling abi here. */
4754 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4755 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4756 int count;
4757 rtx argblock = 0;
4758 CUMULATIVE_ARGS args_so_far_v;
4759 cumulative_args_t args_so_far;
4760 struct arg
4762 rtx value;
4763 machine_mode mode;
4764 rtx reg;
4765 int partial;
4766 struct locate_and_pad_arg_data locate;
4767 rtx save_area;
4769 struct arg *argvec;
4770 int old_inhibit_defer_pop = inhibit_defer_pop;
4771 rtx call_fusage = 0;
4772 rtx mem_value = 0;
4773 rtx valreg;
4774 int pcc_struct_value = 0;
4775 poly_int64 struct_value_size = 0;
4776 int flags;
4777 int reg_parm_stack_space = 0;
4778 poly_int64 needed;
4779 rtx_insn *before_call;
4780 bool have_push_fusage;
4781 tree tfom; /* type_for_mode (outmode, 0) */
4783 #ifdef REG_PARM_STACK_SPACE
4784 /* Define the boundary of the register parm stack space that needs to be
4785 save, if any. */
4786 int low_to_save = 0, high_to_save = 0;
4787 rtx save_area = 0; /* Place that it is saved. */
4788 #endif
4790 /* Size of the stack reserved for parameter registers. */
4791 unsigned int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4792 char *initial_stack_usage_map = stack_usage_map;
4793 unsigned HOST_WIDE_INT initial_stack_usage_watermark = stack_usage_watermark;
4794 char *stack_usage_map_buf = NULL;
4796 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4798 #ifdef REG_PARM_STACK_SPACE
4799 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4800 #endif
4802 /* By default, library functions cannot throw. */
4803 flags = ECF_NOTHROW;
4805 switch (fn_type)
4807 case LCT_NORMAL:
4808 break;
4809 case LCT_CONST:
4810 flags |= ECF_CONST;
4811 break;
4812 case LCT_PURE:
4813 flags |= ECF_PURE;
4814 break;
4815 case LCT_NORETURN:
4816 flags |= ECF_NORETURN;
4817 break;
4818 case LCT_THROW:
4819 flags &= ~ECF_NOTHROW;
4820 break;
4821 case LCT_RETURNS_TWICE:
4822 flags = ECF_RETURNS_TWICE;
4823 break;
4825 fun = orgfun;
4827 /* Ensure current function's preferred stack boundary is at least
4828 what we need. */
4829 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4830 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4832 /* If this kind of value comes back in memory,
4833 decide where in memory it should come back. */
4834 if (outmode != VOIDmode)
4836 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4837 if (aggregate_value_p (tfom, 0))
4839 #ifdef PCC_STATIC_STRUCT_RETURN
4840 rtx pointer_reg
4841 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4842 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4843 pcc_struct_value = 1;
4844 if (value == 0)
4845 value = gen_reg_rtx (outmode);
4846 #else /* not PCC_STATIC_STRUCT_RETURN */
4847 struct_value_size = GET_MODE_SIZE (outmode);
4848 if (value != 0 && MEM_P (value))
4849 mem_value = value;
4850 else
4851 mem_value = assign_temp (tfom, 1, 1);
4852 #endif
4853 /* This call returns a big structure. */
4854 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4857 else
4858 tfom = void_type_node;
4860 /* ??? Unfinished: must pass the memory address as an argument. */
4862 /* Copy all the libcall-arguments out of the varargs data
4863 and into a vector ARGVEC.
4865 Compute how to pass each argument. We only support a very small subset
4866 of the full argument passing conventions to limit complexity here since
4867 library functions shouldn't have many args. */
4869 argvec = XALLOCAVEC (struct arg, nargs + 1);
4870 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4872 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4873 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4874 #else
4875 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4876 #endif
4877 args_so_far = pack_cumulative_args (&args_so_far_v);
4879 args_size.constant = 0;
4880 args_size.var = 0;
4882 count = 0;
4884 push_temp_slots ();
4886 /* If there's a structure value address to be passed,
4887 either pass it in the special place, or pass it as an extra argument. */
4888 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4890 rtx addr = XEXP (mem_value, 0);
4892 nargs++;
4894 /* Make sure it is a reasonable operand for a move or push insn. */
4895 if (!REG_P (addr) && !MEM_P (addr)
4896 && !(CONSTANT_P (addr)
4897 && targetm.legitimate_constant_p (Pmode, addr)))
4898 addr = force_operand (addr, NULL_RTX);
4900 argvec[count].value = addr;
4901 argvec[count].mode = Pmode;
4902 argvec[count].partial = 0;
4904 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4905 Pmode, NULL_TREE, true);
4906 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4907 NULL_TREE, 1) == 0);
4909 locate_and_pad_parm (Pmode, NULL_TREE,
4910 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4912 #else
4913 argvec[count].reg != 0,
4914 #endif
4915 reg_parm_stack_space, 0,
4916 NULL_TREE, &args_size, &argvec[count].locate);
4918 if (argvec[count].reg == 0 || argvec[count].partial != 0
4919 || reg_parm_stack_space > 0)
4920 args_size.constant += argvec[count].locate.size.constant;
4922 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4924 count++;
4927 for (unsigned int i = 0; count < nargs; i++, count++)
4929 rtx val = args[i].first;
4930 machine_mode mode = args[i].second;
4931 int unsigned_p = 0;
4933 /* We cannot convert the arg value to the mode the library wants here;
4934 must do it earlier where we know the signedness of the arg. */
4935 gcc_assert (mode != BLKmode
4936 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4938 /* Make sure it is a reasonable operand for a move or push insn. */
4939 if (!REG_P (val) && !MEM_P (val)
4940 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4941 val = force_operand (val, NULL_RTX);
4943 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4945 rtx slot;
4946 int must_copy
4947 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4949 /* If this was a CONST function, it is now PURE since it now
4950 reads memory. */
4951 if (flags & ECF_CONST)
4953 flags &= ~ECF_CONST;
4954 flags |= ECF_PURE;
4957 if (MEM_P (val) && !must_copy)
4959 tree val_expr = MEM_EXPR (val);
4960 if (val_expr)
4961 mark_addressable (val_expr);
4962 slot = val;
4964 else
4966 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4967 1, 1);
4968 emit_move_insn (slot, val);
4971 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4972 gen_rtx_USE (VOIDmode, slot),
4973 call_fusage);
4974 if (must_copy)
4975 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4976 gen_rtx_CLOBBER (VOIDmode,
4977 slot),
4978 call_fusage);
4980 mode = Pmode;
4981 val = force_operand (XEXP (slot, 0), NULL_RTX);
4984 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4985 argvec[count].mode = mode;
4986 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4987 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4988 NULL_TREE, true);
4990 argvec[count].partial
4991 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4993 if (argvec[count].reg == 0
4994 || argvec[count].partial != 0
4995 || reg_parm_stack_space > 0)
4997 locate_and_pad_parm (mode, NULL_TREE,
4998 #ifdef STACK_PARMS_IN_REG_PARM_AREA
5000 #else
5001 argvec[count].reg != 0,
5002 #endif
5003 reg_parm_stack_space, argvec[count].partial,
5004 NULL_TREE, &args_size, &argvec[count].locate);
5005 args_size.constant += argvec[count].locate.size.constant;
5006 gcc_assert (!argvec[count].locate.size.var);
5008 #ifdef BLOCK_REG_PADDING
5009 else
5010 /* The argument is passed entirely in registers. See at which
5011 end it should be padded. */
5012 argvec[count].locate.where_pad =
5013 BLOCK_REG_PADDING (mode, NULL_TREE,
5014 known_le (GET_MODE_SIZE (mode), UNITS_PER_WORD));
5015 #endif
5017 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
5020 /* If this machine requires an external definition for library
5021 functions, write one out. */
5022 assemble_external_libcall (fun);
5024 original_args_size = args_size;
5025 args_size.constant = (aligned_upper_bound (args_size.constant
5026 + stack_pointer_delta,
5027 STACK_BYTES)
5028 - stack_pointer_delta);
5030 args_size.constant = upper_bound (args_size.constant,
5031 reg_parm_stack_space);
5033 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
5034 args_size.constant -= reg_parm_stack_space;
5036 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
5037 args_size.constant);
5039 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
5041 poly_int64 pushed = args_size.constant + pending_stack_adjust;
5042 current_function_pushed_stack_size
5043 = upper_bound (current_function_pushed_stack_size, pushed);
5046 if (ACCUMULATE_OUTGOING_ARGS)
5048 /* Since the stack pointer will never be pushed, it is possible for
5049 the evaluation of a parm to clobber something we have already
5050 written to the stack. Since most function calls on RISC machines
5051 do not use the stack, this is uncommon, but must work correctly.
5053 Therefore, we save any area of the stack that was already written
5054 and that we are using. Here we set up to do this by making a new
5055 stack usage map from the old one.
5057 Another approach might be to try to reorder the argument
5058 evaluations to avoid this conflicting stack usage. */
5060 needed = args_size.constant;
5062 /* Since we will be writing into the entire argument area, the
5063 map must be allocated for its entire size, not just the part that
5064 is the responsibility of the caller. */
5065 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
5066 needed += reg_parm_stack_space;
5068 poly_int64 limit = needed;
5069 if (ARGS_GROW_DOWNWARD)
5070 limit += 1;
5072 /* For polynomial sizes, this is the maximum possible size needed
5073 for arguments with a constant size and offset. */
5074 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
5075 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
5076 const_limit);
5078 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
5079 stack_usage_map = stack_usage_map_buf;
5081 if (initial_highest_arg_in_use)
5082 memcpy (stack_usage_map, initial_stack_usage_map,
5083 initial_highest_arg_in_use);
5085 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
5086 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
5087 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
5088 needed = 0;
5090 /* We must be careful to use virtual regs before they're instantiated,
5091 and real regs afterwards. Loop optimization, for example, can create
5092 new libcalls after we've instantiated the virtual regs, and if we
5093 use virtuals anyway, they won't match the rtl patterns. */
5095 if (virtuals_instantiated)
5096 argblock = plus_constant (Pmode, stack_pointer_rtx,
5097 STACK_POINTER_OFFSET);
5098 else
5099 argblock = virtual_outgoing_args_rtx;
5101 else
5103 if (!PUSH_ARGS)
5104 argblock = push_block (gen_int_mode (args_size.constant, Pmode), 0, 0);
5107 /* We push args individually in reverse order, perform stack alignment
5108 before the first push (the last arg). */
5109 if (argblock == 0)
5110 anti_adjust_stack (gen_int_mode (args_size.constant
5111 - original_args_size.constant,
5112 Pmode));
5114 argnum = nargs - 1;
5116 #ifdef REG_PARM_STACK_SPACE
5117 if (ACCUMULATE_OUTGOING_ARGS)
5119 /* The argument list is the property of the called routine and it
5120 may clobber it. If the fixed area has been used for previous
5121 parameters, we must save and restore it. */
5122 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
5123 &low_to_save, &high_to_save);
5125 #endif
5127 /* When expanding a normal call, args are stored in push order,
5128 which is the reverse of what we have here. */
5129 bool any_regs = false;
5130 for (int i = nargs; i-- > 0; )
5131 if (argvec[i].reg != NULL_RTX)
5133 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
5134 any_regs = true;
5136 if (!any_regs)
5137 targetm.calls.call_args (pc_rtx, NULL_TREE);
5139 /* Push the args that need to be pushed. */
5141 have_push_fusage = false;
5143 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5144 are to be pushed. */
5145 for (count = 0; count < nargs; count++, argnum--)
5147 machine_mode mode = argvec[argnum].mode;
5148 rtx val = argvec[argnum].value;
5149 rtx reg = argvec[argnum].reg;
5150 int partial = argvec[argnum].partial;
5151 unsigned int parm_align = argvec[argnum].locate.boundary;
5152 poly_int64 lower_bound = 0, upper_bound = 0;
5154 if (! (reg != 0 && partial == 0))
5156 rtx use;
5158 if (ACCUMULATE_OUTGOING_ARGS)
5160 /* If this is being stored into a pre-allocated, fixed-size,
5161 stack area, save any previous data at that location. */
5163 if (ARGS_GROW_DOWNWARD)
5165 /* stack_slot is negative, but we want to index stack_usage_map
5166 with positive values. */
5167 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
5168 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
5170 else
5172 lower_bound = argvec[argnum].locate.slot_offset.constant;
5173 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
5176 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5177 reg_parm_stack_space))
5179 /* We need to make a save area. */
5180 poly_uint64 size
5181 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
5182 machine_mode save_mode
5183 = int_mode_for_size (size, 1).else_blk ();
5184 rtx adr
5185 = plus_constant (Pmode, argblock,
5186 argvec[argnum].locate.offset.constant);
5187 rtx stack_area
5188 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
5190 if (save_mode == BLKmode)
5192 argvec[argnum].save_area
5193 = assign_stack_temp (BLKmode,
5194 argvec[argnum].locate.size.constant
5197 emit_block_move (validize_mem
5198 (copy_rtx (argvec[argnum].save_area)),
5199 stack_area,
5200 (gen_int_mode
5201 (argvec[argnum].locate.size.constant,
5202 Pmode)),
5203 BLOCK_OP_CALL_PARM);
5205 else
5207 argvec[argnum].save_area = gen_reg_rtx (save_mode);
5209 emit_move_insn (argvec[argnum].save_area, stack_area);
5214 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
5215 partial, reg, 0, argblock,
5216 (gen_int_mode
5217 (argvec[argnum].locate.offset.constant, Pmode)),
5218 reg_parm_stack_space,
5219 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
5221 /* Now mark the segment we just used. */
5222 if (ACCUMULATE_OUTGOING_ARGS)
5223 mark_stack_region_used (lower_bound, upper_bound);
5225 NO_DEFER_POP;
5227 /* Indicate argument access so that alias.c knows that these
5228 values are live. */
5229 if (argblock)
5230 use = plus_constant (Pmode, argblock,
5231 argvec[argnum].locate.offset.constant);
5232 else if (have_push_fusage)
5233 continue;
5234 else
5236 /* When arguments are pushed, trying to tell alias.c where
5237 exactly this argument is won't work, because the
5238 auto-increment causes confusion. So we merely indicate
5239 that we access something with a known mode somewhere on
5240 the stack. */
5241 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
5242 gen_rtx_SCRATCH (Pmode));
5243 have_push_fusage = true;
5245 use = gen_rtx_MEM (argvec[argnum].mode, use);
5246 use = gen_rtx_USE (VOIDmode, use);
5247 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
5251 argnum = nargs - 1;
5253 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
5255 /* Now load any reg parms into their regs. */
5257 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5258 are to be pushed. */
5259 for (count = 0; count < nargs; count++, argnum--)
5261 machine_mode mode = argvec[argnum].mode;
5262 rtx val = argvec[argnum].value;
5263 rtx reg = argvec[argnum].reg;
5264 int partial = argvec[argnum].partial;
5266 /* Handle calls that pass values in multiple non-contiguous
5267 locations. The PA64 has examples of this for library calls. */
5268 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5269 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
5270 else if (reg != 0 && partial == 0)
5272 emit_move_insn (reg, val);
5273 #ifdef BLOCK_REG_PADDING
5274 poly_int64 size = GET_MODE_SIZE (argvec[argnum].mode);
5276 /* Copied from load_register_parameters. */
5278 /* Handle case where we have a value that needs shifting
5279 up to the msb. eg. a QImode value and we're padding
5280 upward on a BYTES_BIG_ENDIAN machine. */
5281 if (known_lt (size, UNITS_PER_WORD)
5282 && (argvec[argnum].locate.where_pad
5283 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5285 rtx x;
5286 poly_int64 shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
5288 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5289 report the whole reg as used. Strictly speaking, the
5290 call only uses SIZE bytes at the msb end, but it doesn't
5291 seem worth generating rtl to say that. */
5292 reg = gen_rtx_REG (word_mode, REGNO (reg));
5293 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
5294 if (x != reg)
5295 emit_move_insn (reg, x);
5297 #endif
5300 NO_DEFER_POP;
5303 /* Any regs containing parms remain in use through the call. */
5304 for (count = 0; count < nargs; count++)
5306 rtx reg = argvec[count].reg;
5307 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5308 use_group_regs (&call_fusage, reg);
5309 else if (reg != 0)
5311 int partial = argvec[count].partial;
5312 if (partial)
5314 int nregs;
5315 gcc_assert (partial % UNITS_PER_WORD == 0);
5316 nregs = partial / UNITS_PER_WORD;
5317 use_regs (&call_fusage, REGNO (reg), nregs);
5319 else
5320 use_reg (&call_fusage, reg);
5324 /* Pass the function the address in which to return a structure value. */
5325 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
5327 emit_move_insn (struct_value,
5328 force_reg (Pmode,
5329 force_operand (XEXP (mem_value, 0),
5330 NULL_RTX)));
5331 if (REG_P (struct_value))
5332 use_reg (&call_fusage, struct_value);
5335 /* Don't allow popping to be deferred, since then
5336 cse'ing of library calls could delete a call and leave the pop. */
5337 NO_DEFER_POP;
5338 valreg = (mem_value == 0 && outmode != VOIDmode
5339 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
5341 /* Stack must be properly aligned now. */
5342 gcc_assert (multiple_p (stack_pointer_delta,
5343 PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT));
5345 before_call = get_last_insn ();
5347 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5348 will set inhibit_defer_pop to that value. */
5349 /* The return type is needed to decide how many bytes the function pops.
5350 Signedness plays no role in that, so for simplicity, we pretend it's
5351 always signed. We also assume that the list of arguments passed has
5352 no impact, so we pretend it is unknown. */
5354 emit_call_1 (fun, NULL,
5355 get_identifier (XSTR (orgfun, 0)),
5356 build_function_type (tfom, NULL_TREE),
5357 original_args_size.constant, args_size.constant,
5358 struct_value_size,
5359 targetm.calls.function_arg (args_so_far,
5360 VOIDmode, void_type_node, true),
5361 valreg,
5362 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
5364 if (flag_ipa_ra)
5366 rtx datum = orgfun;
5367 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
5368 rtx_call_insn *last = last_call_insn ();
5369 add_reg_note (last, REG_CALL_DECL, datum);
5372 /* Right-shift returned value if necessary. */
5373 if (!pcc_struct_value
5374 && TYPE_MODE (tfom) != BLKmode
5375 && targetm.calls.return_in_msb (tfom))
5377 shift_return_value (TYPE_MODE (tfom), false, valreg);
5378 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5381 targetm.calls.end_call_args ();
5383 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5384 that it should complain if nonvolatile values are live. For
5385 functions that cannot return, inform flow that control does not
5386 fall through. */
5387 if (flags & ECF_NORETURN)
5389 /* The barrier note must be emitted
5390 immediately after the CALL_INSN. Some ports emit more than
5391 just a CALL_INSN above, so we must search for it here. */
5392 rtx_insn *last = get_last_insn ();
5393 while (!CALL_P (last))
5395 last = PREV_INSN (last);
5396 /* There was no CALL_INSN? */
5397 gcc_assert (last != before_call);
5400 emit_barrier_after (last);
5403 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5404 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5405 if (flags & ECF_NOTHROW)
5407 rtx_insn *last = get_last_insn ();
5408 while (!CALL_P (last))
5410 last = PREV_INSN (last);
5411 /* There was no CALL_INSN? */
5412 gcc_assert (last != before_call);
5415 make_reg_eh_region_note_nothrow_nononlocal (last);
5418 /* Now restore inhibit_defer_pop to its actual original value. */
5419 OK_DEFER_POP;
5421 pop_temp_slots ();
5423 /* Copy the value to the right place. */
5424 if (outmode != VOIDmode && retval)
5426 if (mem_value)
5428 if (value == 0)
5429 value = mem_value;
5430 if (value != mem_value)
5431 emit_move_insn (value, mem_value);
5433 else if (GET_CODE (valreg) == PARALLEL)
5435 if (value == 0)
5436 value = gen_reg_rtx (outmode);
5437 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5439 else
5441 /* Convert to the proper mode if a promotion has been active. */
5442 if (GET_MODE (valreg) != outmode)
5444 int unsignedp = TYPE_UNSIGNED (tfom);
5446 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5447 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5448 == GET_MODE (valreg));
5449 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5452 if (value != 0)
5453 emit_move_insn (value, valreg);
5454 else
5455 value = valreg;
5459 if (ACCUMULATE_OUTGOING_ARGS)
5461 #ifdef REG_PARM_STACK_SPACE
5462 if (save_area)
5463 restore_fixed_argument_area (save_area, argblock,
5464 high_to_save, low_to_save);
5465 #endif
5467 /* If we saved any argument areas, restore them. */
5468 for (count = 0; count < nargs; count++)
5469 if (argvec[count].save_area)
5471 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5472 rtx adr = plus_constant (Pmode, argblock,
5473 argvec[count].locate.offset.constant);
5474 rtx stack_area = gen_rtx_MEM (save_mode,
5475 memory_address (save_mode, adr));
5477 if (save_mode == BLKmode)
5478 emit_block_move (stack_area,
5479 validize_mem
5480 (copy_rtx (argvec[count].save_area)),
5481 (gen_int_mode
5482 (argvec[count].locate.size.constant, Pmode)),
5483 BLOCK_OP_CALL_PARM);
5484 else
5485 emit_move_insn (stack_area, argvec[count].save_area);
5488 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5489 stack_usage_map = initial_stack_usage_map;
5490 stack_usage_watermark = initial_stack_usage_watermark;
5493 free (stack_usage_map_buf);
5495 return value;
5500 /* Store pointer bounds argument ARG into Bounds Table entry
5501 associated with PARM. */
5502 static void
5503 store_bounds (struct arg_data *arg, struct arg_data *parm)
5505 rtx slot = NULL, ptr = NULL, addr = NULL;
5507 /* We may pass bounds not associated with any pointer. */
5508 if (!parm)
5510 gcc_assert (arg->special_slot);
5511 slot = arg->special_slot;
5512 ptr = const0_rtx;
5514 /* Find pointer associated with bounds and where it is
5515 passed. */
5516 else
5518 if (!parm->reg)
5520 gcc_assert (!arg->special_slot);
5522 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5524 else if (REG_P (parm->reg))
5526 gcc_assert (arg->special_slot);
5527 slot = arg->special_slot;
5529 if (MEM_P (parm->value))
5530 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5531 else if (REG_P (parm->value))
5532 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5533 else
5535 gcc_assert (!arg->pointer_offset);
5536 ptr = parm->value;
5539 else
5541 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5543 gcc_assert (arg->special_slot);
5544 slot = arg->special_slot;
5546 if (parm->parallel_value)
5547 ptr = chkp_get_value_with_offs (parm->parallel_value,
5548 GEN_INT (arg->pointer_offset));
5549 else
5550 gcc_unreachable ();
5554 /* Expand bounds. */
5555 if (!arg->value)
5556 arg->value = expand_normal (arg->tree_value);
5558 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5561 /* Store a single argument for a function call
5562 into the register or memory area where it must be passed.
5563 *ARG describes the argument value and where to pass it.
5565 ARGBLOCK is the address of the stack-block for all the arguments,
5566 or 0 on a machine where arguments are pushed individually.
5568 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5569 so must be careful about how the stack is used.
5571 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5572 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5573 that we need not worry about saving and restoring the stack.
5575 FNDECL is the declaration of the function we are calling.
5577 Return nonzero if this arg should cause sibcall failure,
5578 zero otherwise. */
5580 static int
5581 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5582 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5584 tree pval = arg->tree_value;
5585 rtx reg = 0;
5586 int partial = 0;
5587 poly_int64 used = 0;
5588 poly_int64 lower_bound = 0, upper_bound = 0;
5589 int sibcall_failure = 0;
5591 if (TREE_CODE (pval) == ERROR_MARK)
5592 return 1;
5594 /* Push a new temporary level for any temporaries we make for
5595 this argument. */
5596 push_temp_slots ();
5598 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5600 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5601 save any previous data at that location. */
5602 if (argblock && ! variable_size && arg->stack)
5604 if (ARGS_GROW_DOWNWARD)
5606 /* stack_slot is negative, but we want to index stack_usage_map
5607 with positive values. */
5608 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5610 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5611 upper_bound = -rtx_to_poly_int64 (offset) + 1;
5613 else
5614 upper_bound = 0;
5616 lower_bound = upper_bound - arg->locate.size.constant;
5618 else
5620 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5622 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5623 lower_bound = rtx_to_poly_int64 (offset);
5625 else
5626 lower_bound = 0;
5628 upper_bound = lower_bound + arg->locate.size.constant;
5631 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5632 reg_parm_stack_space))
5634 /* We need to make a save area. */
5635 poly_uint64 size = arg->locate.size.constant * BITS_PER_UNIT;
5636 machine_mode save_mode
5637 = int_mode_for_size (size, 1).else_blk ();
5638 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5639 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5641 if (save_mode == BLKmode)
5643 arg->save_area
5644 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5645 preserve_temp_slots (arg->save_area);
5646 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5647 stack_area,
5648 (gen_int_mode
5649 (arg->locate.size.constant, Pmode)),
5650 BLOCK_OP_CALL_PARM);
5652 else
5654 arg->save_area = gen_reg_rtx (save_mode);
5655 emit_move_insn (arg->save_area, stack_area);
5661 /* If this isn't going to be placed on both the stack and in registers,
5662 set up the register and number of words. */
5663 if (! arg->pass_on_stack)
5665 if (flags & ECF_SIBCALL)
5666 reg = arg->tail_call_reg;
5667 else
5668 reg = arg->reg;
5669 partial = arg->partial;
5672 /* Being passed entirely in a register. We shouldn't be called in
5673 this case. */
5674 gcc_assert (reg == 0 || partial != 0);
5676 /* If this arg needs special alignment, don't load the registers
5677 here. */
5678 if (arg->n_aligned_regs != 0)
5679 reg = 0;
5681 /* If this is being passed partially in a register, we can't evaluate
5682 it directly into its stack slot. Otherwise, we can. */
5683 if (arg->value == 0)
5685 /* stack_arg_under_construction is nonzero if a function argument is
5686 being evaluated directly into the outgoing argument list and
5687 expand_call must take special action to preserve the argument list
5688 if it is called recursively.
5690 For scalar function arguments stack_usage_map is sufficient to
5691 determine which stack slots must be saved and restored. Scalar
5692 arguments in general have pass_on_stack == 0.
5694 If this argument is initialized by a function which takes the
5695 address of the argument (a C++ constructor or a C function
5696 returning a BLKmode structure), then stack_usage_map is
5697 insufficient and expand_call must push the stack around the
5698 function call. Such arguments have pass_on_stack == 1.
5700 Note that it is always safe to set stack_arg_under_construction,
5701 but this generates suboptimal code if set when not needed. */
5703 if (arg->pass_on_stack)
5704 stack_arg_under_construction++;
5706 arg->value = expand_expr (pval,
5707 (partial
5708 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5709 ? NULL_RTX : arg->stack,
5710 VOIDmode, EXPAND_STACK_PARM);
5712 /* If we are promoting object (or for any other reason) the mode
5713 doesn't agree, convert the mode. */
5715 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5716 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5717 arg->value, arg->unsignedp);
5719 if (arg->pass_on_stack)
5720 stack_arg_under_construction--;
5723 /* Check for overlap with already clobbered argument area. */
5724 if ((flags & ECF_SIBCALL)
5725 && MEM_P (arg->value)
5726 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg->value, 0),
5727 arg->locate.size.constant))
5728 sibcall_failure = 1;
5730 /* Don't allow anything left on stack from computation
5731 of argument to alloca. */
5732 if (flags & ECF_MAY_BE_ALLOCA)
5733 do_pending_stack_adjust ();
5735 if (arg->value == arg->stack)
5736 /* If the value is already in the stack slot, we are done. */
5738 else if (arg->mode != BLKmode)
5740 unsigned int parm_align;
5742 /* Argument is a scalar, not entirely passed in registers.
5743 (If part is passed in registers, arg->partial says how much
5744 and emit_push_insn will take care of putting it there.)
5746 Push it, and if its size is less than the
5747 amount of space allocated to it,
5748 also bump stack pointer by the additional space.
5749 Note that in C the default argument promotions
5750 will prevent such mismatches. */
5752 poly_int64 size = (TYPE_EMPTY_P (TREE_TYPE (pval))
5753 ? 0 : GET_MODE_SIZE (arg->mode));
5755 /* Compute how much space the push instruction will push.
5756 On many machines, pushing a byte will advance the stack
5757 pointer by a halfword. */
5758 #ifdef PUSH_ROUNDING
5759 size = PUSH_ROUNDING (size);
5760 #endif
5761 used = size;
5763 /* Compute how much space the argument should get:
5764 round up to a multiple of the alignment for arguments. */
5765 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5766 != PAD_NONE)
5767 /* At the moment we don't (need to) support ABIs for which the
5768 padding isn't known at compile time. In principle it should
5769 be easy to add though. */
5770 used = force_align_up (size, PARM_BOUNDARY / BITS_PER_UNIT);
5772 /* Compute the alignment of the pushed argument. */
5773 parm_align = arg->locate.boundary;
5774 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5775 == PAD_DOWNWARD)
5777 poly_int64 pad = used - size;
5778 unsigned int pad_align = known_alignment (pad) * BITS_PER_UNIT;
5779 if (pad_align != 0)
5780 parm_align = MIN (parm_align, pad_align);
5783 /* This isn't already where we want it on the stack, so put it there.
5784 This can either be done with push or copy insns. */
5785 if (maybe_ne (used, 0)
5786 && !emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval),
5787 NULL_RTX, parm_align, partial, reg, used - size,
5788 argblock, ARGS_SIZE_RTX (arg->locate.offset),
5789 reg_parm_stack_space,
5790 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5791 sibcall_failure = 1;
5793 /* Unless this is a partially-in-register argument, the argument is now
5794 in the stack. */
5795 if (partial == 0)
5796 arg->value = arg->stack;
5798 else
5800 /* BLKmode, at least partly to be pushed. */
5802 unsigned int parm_align;
5803 poly_int64 excess;
5804 rtx size_rtx;
5806 /* Pushing a nonscalar.
5807 If part is passed in registers, PARTIAL says how much
5808 and emit_push_insn will take care of putting it there. */
5810 /* Round its size up to a multiple
5811 of the allocation unit for arguments. */
5813 if (arg->locate.size.var != 0)
5815 excess = 0;
5816 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5818 else
5820 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5821 for BLKmode is careful to avoid it. */
5822 excess = (arg->locate.size.constant
5823 - arg_int_size_in_bytes (TREE_TYPE (pval))
5824 + partial);
5825 size_rtx = expand_expr (arg_size_in_bytes (TREE_TYPE (pval)),
5826 NULL_RTX, TYPE_MODE (sizetype),
5827 EXPAND_NORMAL);
5830 parm_align = arg->locate.boundary;
5832 /* When an argument is padded down, the block is aligned to
5833 PARM_BOUNDARY, but the actual argument isn't. */
5834 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5835 == PAD_DOWNWARD)
5837 if (arg->locate.size.var)
5838 parm_align = BITS_PER_UNIT;
5839 else
5841 unsigned int excess_align
5842 = known_alignment (excess) * BITS_PER_UNIT;
5843 if (excess_align != 0)
5844 parm_align = MIN (parm_align, excess_align);
5848 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5850 /* emit_push_insn might not work properly if arg->value and
5851 argblock + arg->locate.offset areas overlap. */
5852 rtx x = arg->value;
5853 poly_int64 i = 0;
5855 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5856 || (GET_CODE (XEXP (x, 0)) == PLUS
5857 && XEXP (XEXP (x, 0), 0) ==
5858 crtl->args.internal_arg_pointer
5859 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5861 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5862 i = rtx_to_poly_int64 (XEXP (XEXP (x, 0), 1));
5864 /* arg.locate doesn't contain the pretend_args_size offset,
5865 it's part of argblock. Ensure we don't count it in I. */
5866 if (STACK_GROWS_DOWNWARD)
5867 i -= crtl->args.pretend_args_size;
5868 else
5869 i += crtl->args.pretend_args_size;
5871 /* expand_call should ensure this. */
5872 gcc_assert (!arg->locate.offset.var
5873 && arg->locate.size.var == 0);
5874 poly_int64 size_val = rtx_to_poly_int64 (size_rtx);
5876 if (known_eq (arg->locate.offset.constant, i))
5878 /* Even though they appear to be at the same location,
5879 if part of the outgoing argument is in registers,
5880 they aren't really at the same location. Check for
5881 this by making sure that the incoming size is the
5882 same as the outgoing size. */
5883 if (maybe_ne (arg->locate.size.constant, size_val))
5884 sibcall_failure = 1;
5886 else if (maybe_in_range_p (arg->locate.offset.constant,
5887 i, size_val))
5888 sibcall_failure = 1;
5889 /* Use arg->locate.size.constant instead of size_rtx
5890 because we only care about the part of the argument
5891 on the stack. */
5892 else if (maybe_in_range_p (i, arg->locate.offset.constant,
5893 arg->locate.size.constant))
5894 sibcall_failure = 1;
5898 if (!CONST_INT_P (size_rtx) || INTVAL (size_rtx) != 0)
5899 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5900 parm_align, partial, reg, excess, argblock,
5901 ARGS_SIZE_RTX (arg->locate.offset),
5902 reg_parm_stack_space,
5903 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5905 /* Unless this is a partially-in-register argument, the argument is now
5906 in the stack.
5908 ??? Unlike the case above, in which we want the actual
5909 address of the data, so that we can load it directly into a
5910 register, here we want the address of the stack slot, so that
5911 it's properly aligned for word-by-word copying or something
5912 like that. It's not clear that this is always correct. */
5913 if (partial == 0)
5914 arg->value = arg->stack_slot;
5917 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5919 tree type = TREE_TYPE (arg->tree_value);
5920 arg->parallel_value
5921 = emit_group_load_into_temps (arg->reg, arg->value, type,
5922 int_size_in_bytes (type));
5925 /* Mark all slots this store used. */
5926 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5927 && argblock && ! variable_size && arg->stack)
5928 mark_stack_region_used (lower_bound, upper_bound);
5930 /* Once we have pushed something, pops can't safely
5931 be deferred during the rest of the arguments. */
5932 NO_DEFER_POP;
5934 /* Free any temporary slots made in processing this argument. */
5935 pop_temp_slots ();
5937 return sibcall_failure;
5940 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5942 bool
5943 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5944 const_tree type)
5946 if (!type)
5947 return false;
5949 /* If the type has variable size... */
5950 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5951 return true;
5953 /* If the type is marked as addressable (it is required
5954 to be constructed into the stack)... */
5955 if (TREE_ADDRESSABLE (type))
5956 return true;
5958 return false;
5961 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5962 takes trailing padding of a structure into account. */
5963 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5965 bool
5966 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5968 if (!type)
5969 return false;
5971 /* If the type has variable size... */
5972 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5973 return true;
5975 /* If the type is marked as addressable (it is required
5976 to be constructed into the stack)... */
5977 if (TREE_ADDRESSABLE (type))
5978 return true;
5980 if (TYPE_EMPTY_P (type))
5981 return false;
5983 /* If the padding and mode of the type is such that a copy into
5984 a register would put it into the wrong part of the register. */
5985 if (mode == BLKmode
5986 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5987 && (targetm.calls.function_arg_padding (mode, type)
5988 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5989 return true;
5991 return false;
5994 /* Tell the garbage collector about GTY markers in this source file. */
5995 #include "gt-calls.h"