* c-ada-spec.c (dump_number): Add FLOAT_P parameter.
[official-gcc.git] / gcc / calls.c
blob54fea1586312e06d49e9ea2b858e92e831f76780
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"
59 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
60 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
62 /* Data structure and subroutines used within expand_call. */
64 struct arg_data
66 /* Tree node for this argument. */
67 tree tree_value;
68 /* Mode for value; TYPE_MODE unless promoted. */
69 machine_mode mode;
70 /* Current RTL value for argument, or 0 if it isn't precomputed. */
71 rtx value;
72 /* Initially-compute RTL value for argument; only for const functions. */
73 rtx initial_value;
74 /* Register to pass this argument in, 0 if passed on stack, or an
75 PARALLEL if the arg is to be copied into multiple non-contiguous
76 registers. */
77 rtx reg;
78 /* Register to pass this argument in when generating tail call sequence.
79 This is not the same register as for normal calls on machines with
80 register windows. */
81 rtx tail_call_reg;
82 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
83 form for emit_group_move. */
84 rtx parallel_value;
85 /* If value is passed in neither reg nor stack, this field holds a number
86 of a special slot to be used. */
87 rtx special_slot;
88 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
89 there is no such pointer. */
90 int pointer_arg;
91 /* If pointer_arg refers a structure, then pointer_offset holds an offset
92 of a pointer in this structure. */
93 int pointer_offset;
94 /* If REG was promoted from the actual mode of the argument expression,
95 indicates whether the promotion is sign- or zero-extended. */
96 int unsignedp;
97 /* Number of bytes to put in registers. 0 means put the whole arg
98 in registers. Also 0 if not passed in registers. */
99 int partial;
100 /* Nonzero if argument must be passed on stack.
101 Note that some arguments may be passed on the stack
102 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
103 pass_on_stack identifies arguments that *cannot* go in registers. */
104 int pass_on_stack;
105 /* Some fields packaged up for locate_and_pad_parm. */
106 struct locate_and_pad_arg_data locate;
107 /* Location on the stack at which parameter should be stored. The store
108 has already been done if STACK == VALUE. */
109 rtx stack;
110 /* Location on the stack of the start of this argument slot. This can
111 differ from STACK if this arg pads downward. This location is known
112 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
113 rtx stack_slot;
114 /* Place that this stack area has been saved, if needed. */
115 rtx save_area;
116 /* If an argument's alignment does not permit direct copying into registers,
117 copy in smaller-sized pieces into pseudos. These are stored in a
118 block pointed to by this field. The next field says how many
119 word-sized pseudos we made. */
120 rtx *aligned_regs;
121 int n_aligned_regs;
124 /* A vector of one char per byte of stack space. A byte if nonzero if
125 the corresponding stack location has been used.
126 This vector is used to prevent a function call within an argument from
127 clobbering any stack already set up. */
128 static char *stack_usage_map;
130 /* Size of STACK_USAGE_MAP. */
131 static unsigned int highest_outgoing_arg_in_use;
133 /* Assume that any stack location at this byte index is used,
134 without checking the contents of stack_usage_map. */
135 static unsigned HOST_WIDE_INT stack_usage_watermark = HOST_WIDE_INT_M1U;
137 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
138 stack location's tail call argument has been already stored into the stack.
139 This bitmap is used to prevent sibling call optimization if function tries
140 to use parent's incoming argument slots when they have been already
141 overwritten with tail call arguments. */
142 static sbitmap stored_args_map;
144 /* Assume that any virtual-incoming location at this byte index has been
145 stored, without checking the contents of stored_args_map. */
146 static unsigned HOST_WIDE_INT stored_args_watermark;
148 /* stack_arg_under_construction is nonzero when an argument may be
149 initialized with a constructor call (including a C function that
150 returns a BLKmode struct) and expand_call must take special action
151 to make sure the object being constructed does not overlap the
152 argument list for the constructor call. */
153 static int stack_arg_under_construction;
155 static void precompute_register_parameters (int, struct arg_data *, int *);
156 static void store_bounds (struct arg_data *, struct arg_data *);
157 static int store_one_arg (struct arg_data *, rtx, int, int, int);
158 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
159 static int finalize_must_preallocate (int, int, struct arg_data *,
160 struct args_size *);
161 static void precompute_arguments (int, struct arg_data *);
162 static void compute_argument_addresses (struct arg_data *, rtx, int);
163 static rtx rtx_for_function_call (tree, tree);
164 static void load_register_parameters (struct arg_data *, int, rtx *, int,
165 int, int *);
166 static int special_function_p (const_tree, int);
167 static int check_sibcall_argument_overlap_1 (rtx);
168 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
170 static tree split_complex_types (tree);
172 #ifdef REG_PARM_STACK_SPACE
173 static rtx save_fixed_argument_area (int, rtx, int *, int *);
174 static void restore_fixed_argument_area (rtx, rtx, int, int);
175 #endif
177 /* Return true if bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
178 stack region might already be in use. */
180 static bool
181 stack_region_maybe_used_p (poly_uint64 lower_bound, poly_uint64 upper_bound,
182 unsigned int reg_parm_stack_space)
184 unsigned HOST_WIDE_INT const_lower, const_upper;
185 const_lower = constant_lower_bound (lower_bound);
186 if (!upper_bound.is_constant (&const_upper))
187 const_upper = HOST_WIDE_INT_M1U;
189 if (const_upper > stack_usage_watermark)
190 return true;
192 /* Don't worry about things in the fixed argument area;
193 it has already been saved. */
194 const_lower = MAX (const_lower, reg_parm_stack_space);
195 const_upper = MIN (const_upper, highest_outgoing_arg_in_use);
196 for (unsigned HOST_WIDE_INT i = const_lower; i < const_upper; ++i)
197 if (stack_usage_map[i])
198 return true;
199 return false;
202 /* Record that bytes [LOWER_BOUND, UPPER_BOUND) of the outgoing
203 stack region are now in use. */
205 static void
206 mark_stack_region_used (poly_uint64 lower_bound, poly_uint64 upper_bound)
208 unsigned HOST_WIDE_INT const_lower, const_upper;
209 const_lower = constant_lower_bound (lower_bound);
210 if (upper_bound.is_constant (&const_upper))
211 for (unsigned HOST_WIDE_INT i = const_lower; i < const_upper; ++i)
212 stack_usage_map[i] = 1;
213 else
214 stack_usage_watermark = MIN (stack_usage_watermark, const_lower);
217 /* Force FUNEXP into a form suitable for the address of a CALL,
218 and return that as an rtx. Also load the static chain register
219 if FNDECL is a nested function.
221 CALL_FUSAGE points to a variable holding the prospective
222 CALL_INSN_FUNCTION_USAGE information. */
225 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
226 rtx *call_fusage, int reg_parm_seen, int flags)
228 /* Make a valid memory address and copy constants through pseudo-regs,
229 but not for a constant address if -fno-function-cse. */
230 if (GET_CODE (funexp) != SYMBOL_REF)
232 /* If it's an indirect call by descriptor, generate code to perform
233 runtime identification of the pointer and load the descriptor. */
234 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
236 const int bit_val = targetm.calls.custom_function_descriptors;
237 rtx call_lab = gen_label_rtx ();
239 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
240 fndecl_or_type
241 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
242 fndecl_or_type);
243 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
244 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
246 if (GET_MODE (funexp) != Pmode)
247 funexp = convert_memory_address (Pmode, funexp);
249 /* Avoid long live ranges around function calls. */
250 funexp = copy_to_mode_reg (Pmode, funexp);
252 if (REG_P (chain))
253 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
255 /* Emit the runtime identification pattern. */
256 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
257 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
258 call_lab);
260 /* Statically predict the branch to very likely taken. */
261 rtx_insn *insn = get_last_insn ();
262 if (JUMP_P (insn))
263 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
265 /* Load the descriptor. */
266 rtx mem = gen_rtx_MEM (ptr_mode,
267 plus_constant (Pmode, funexp, - bit_val));
268 MEM_NOTRAP_P (mem) = 1;
269 mem = convert_memory_address (Pmode, mem);
270 emit_move_insn (chain, mem);
272 mem = gen_rtx_MEM (ptr_mode,
273 plus_constant (Pmode, funexp,
274 POINTER_SIZE / BITS_PER_UNIT
275 - bit_val));
276 MEM_NOTRAP_P (mem) = 1;
277 mem = convert_memory_address (Pmode, mem);
278 emit_move_insn (funexp, mem);
280 emit_label (call_lab);
282 if (REG_P (chain))
284 use_reg (call_fusage, chain);
285 STATIC_CHAIN_REG_P (chain) = 1;
288 /* Make sure we're not going to be overwritten below. */
289 gcc_assert (!static_chain_value);
292 /* If we are using registers for parameters, force the
293 function address into a register now. */
294 funexp = ((reg_parm_seen
295 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
296 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
297 : memory_address (FUNCTION_MODE, funexp));
299 else
301 /* funexp could be a SYMBOL_REF represents a function pointer which is
302 of ptr_mode. In this case, it should be converted into address mode
303 to be a valid address for memory rtx pattern. See PR 64971. */
304 if (GET_MODE (funexp) != Pmode)
305 funexp = convert_memory_address (Pmode, funexp);
307 if (!(flags & ECF_SIBCALL))
309 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
310 funexp = force_reg (Pmode, funexp);
314 if (static_chain_value != 0
315 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
316 || DECL_STATIC_CHAIN (fndecl_or_type)))
318 rtx chain;
320 chain = targetm.calls.static_chain (fndecl_or_type, false);
321 static_chain_value = convert_memory_address (Pmode, static_chain_value);
323 emit_move_insn (chain, static_chain_value);
324 if (REG_P (chain))
326 use_reg (call_fusage, chain);
327 STATIC_CHAIN_REG_P (chain) = 1;
331 return funexp;
334 /* Generate instructions to call function FUNEXP,
335 and optionally pop the results.
336 The CALL_INSN is the first insn generated.
338 FNDECL is the declaration node of the function. This is given to the
339 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
340 its own args.
342 FUNTYPE is the data type of the function. This is given to the hook
343 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
344 own args. We used to allow an identifier for library functions, but
345 that doesn't work when the return type is an aggregate type and the
346 calling convention says that the pointer to this aggregate is to be
347 popped by the callee.
349 STACK_SIZE is the number of bytes of arguments on the stack,
350 ROUNDED_STACK_SIZE is that number rounded up to
351 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
352 both to put into the call insn and to generate explicit popping
353 code if necessary.
355 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
356 It is zero if this call doesn't want a structure value.
358 NEXT_ARG_REG is the rtx that results from executing
359 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
360 just after all the args have had their registers assigned.
361 This could be whatever you like, but normally it is the first
362 arg-register beyond those used for args in this call,
363 or 0 if all the arg-registers are used in this call.
364 It is passed on to `gen_call' so you can put this info in the call insn.
366 VALREG is a hard register in which a value is returned,
367 or 0 if the call does not return a value.
369 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
370 the args to this call were processed.
371 We restore `inhibit_defer_pop' to that value.
373 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
374 denote registers used by the called function. */
376 static void
377 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
378 tree funtype ATTRIBUTE_UNUSED,
379 poly_int64 stack_size ATTRIBUTE_UNUSED,
380 poly_int64 rounded_stack_size,
381 poly_int64 struct_value_size ATTRIBUTE_UNUSED,
382 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
383 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
384 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
386 rtx rounded_stack_size_rtx = gen_int_mode (rounded_stack_size, Pmode);
387 rtx call, funmem, pat;
388 int already_popped = 0;
389 poly_int64 n_popped = 0;
391 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
392 patterns exist). Any popping that the callee does on return will
393 be from our caller's frame rather than ours. */
394 if (!(ecf_flags & ECF_SIBCALL))
396 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
398 #ifdef CALL_POPS_ARGS
399 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
400 #endif
403 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
404 and we don't want to load it into a register as an optimization,
405 because prepare_call_address already did it if it should be done. */
406 if (GET_CODE (funexp) != SYMBOL_REF)
407 funexp = memory_address (FUNCTION_MODE, funexp);
409 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
410 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
412 tree t = fndecl;
414 /* Although a built-in FUNCTION_DECL and its non-__builtin
415 counterpart compare equal and get a shared mem_attrs, they
416 produce different dump output in compare-debug compilations,
417 if an entry gets garbage collected in one compilation, then
418 adds a different (but equivalent) entry, while the other
419 doesn't run the garbage collector at the same spot and then
420 shares the mem_attr with the equivalent entry. */
421 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
423 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
424 if (t2)
425 t = t2;
428 set_mem_expr (funmem, t);
430 else if (fntree)
431 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
433 if (ecf_flags & ECF_SIBCALL)
435 if (valreg)
436 pat = targetm.gen_sibcall_value (valreg, funmem,
437 rounded_stack_size_rtx,
438 next_arg_reg, NULL_RTX);
439 else
440 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
441 next_arg_reg,
442 gen_int_mode (struct_value_size, Pmode));
444 /* If the target has "call" or "call_value" insns, then prefer them
445 if no arguments are actually popped. If the target does not have
446 "call" or "call_value" insns, then we must use the popping versions
447 even if the call has no arguments to pop. */
448 else if (maybe_ne (n_popped, 0)
449 || !(valreg
450 ? targetm.have_call_value ()
451 : targetm.have_call ()))
453 rtx n_pop = gen_int_mode (n_popped, Pmode);
455 /* If this subroutine pops its own args, record that in the call insn
456 if possible, for the sake of frame pointer elimination. */
458 if (valreg)
459 pat = targetm.gen_call_value_pop (valreg, funmem,
460 rounded_stack_size_rtx,
461 next_arg_reg, n_pop);
462 else
463 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
464 next_arg_reg, n_pop);
466 already_popped = 1;
468 else
470 if (valreg)
471 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
472 next_arg_reg, NULL_RTX);
473 else
474 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
475 gen_int_mode (struct_value_size, Pmode));
477 emit_insn (pat);
479 /* Find the call we just emitted. */
480 rtx_call_insn *call_insn = last_call_insn ();
482 /* Some target create a fresh MEM instead of reusing the one provided
483 above. Set its MEM_EXPR. */
484 call = get_call_rtx_from (call_insn);
485 if (call
486 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
487 && MEM_EXPR (funmem) != NULL_TREE)
488 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
490 /* Mark instrumented calls. */
491 if (call && fntree)
492 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
494 /* Put the register usage information there. */
495 add_function_usage_to (call_insn, call_fusage);
497 /* If this is a const call, then set the insn's unchanging bit. */
498 if (ecf_flags & ECF_CONST)
499 RTL_CONST_CALL_P (call_insn) = 1;
501 /* If this is a pure call, then set the insn's unchanging bit. */
502 if (ecf_flags & ECF_PURE)
503 RTL_PURE_CALL_P (call_insn) = 1;
505 /* If this is a const call, then set the insn's unchanging bit. */
506 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
507 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
509 /* Create a nothrow REG_EH_REGION note, if needed. */
510 make_reg_eh_region_note (call_insn, ecf_flags, 0);
512 if (ecf_flags & ECF_NORETURN)
513 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
515 if (ecf_flags & ECF_RETURNS_TWICE)
517 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
518 cfun->calls_setjmp = 1;
521 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
523 /* Restore this now, so that we do defer pops for this call's args
524 if the context of the call as a whole permits. */
525 inhibit_defer_pop = old_inhibit_defer_pop;
527 if (maybe_ne (n_popped, 0))
529 if (!already_popped)
530 CALL_INSN_FUNCTION_USAGE (call_insn)
531 = gen_rtx_EXPR_LIST (VOIDmode,
532 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
533 CALL_INSN_FUNCTION_USAGE (call_insn));
534 rounded_stack_size -= n_popped;
535 rounded_stack_size_rtx = gen_int_mode (rounded_stack_size, Pmode);
536 stack_pointer_delta -= n_popped;
538 add_args_size_note (call_insn, stack_pointer_delta);
540 /* If popup is needed, stack realign must use DRAP */
541 if (SUPPORTS_STACK_ALIGNMENT)
542 crtl->need_drap = true;
544 /* For noreturn calls when not accumulating outgoing args force
545 REG_ARGS_SIZE note to prevent crossjumping of calls with different
546 args sizes. */
547 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
548 add_args_size_note (call_insn, stack_pointer_delta);
550 if (!ACCUMULATE_OUTGOING_ARGS)
552 /* If returning from the subroutine does not automatically pop the args,
553 we need an instruction to pop them sooner or later.
554 Perhaps do it now; perhaps just record how much space to pop later.
556 If returning from the subroutine does pop the args, indicate that the
557 stack pointer will be changed. */
559 if (maybe_ne (rounded_stack_size, 0))
561 if (ecf_flags & ECF_NORETURN)
562 /* Just pretend we did the pop. */
563 stack_pointer_delta -= rounded_stack_size;
564 else if (flag_defer_pop && inhibit_defer_pop == 0
565 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
566 pending_stack_adjust += rounded_stack_size;
567 else
568 adjust_stack (rounded_stack_size_rtx);
571 /* When we accumulate outgoing args, we must avoid any stack manipulations.
572 Restore the stack pointer to its original value now. Usually
573 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
574 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
575 popping variants of functions exist as well.
577 ??? We may optimize similar to defer_pop above, but it is
578 probably not worthwhile.
580 ??? It will be worthwhile to enable combine_stack_adjustments even for
581 such machines. */
582 else if (maybe_ne (n_popped, 0))
583 anti_adjust_stack (gen_int_mode (n_popped, Pmode));
586 /* Determine if the function identified by FNDECL is one with
587 special properties we wish to know about. Modify FLAGS accordingly.
589 For example, if the function might return more than one time (setjmp), then
590 set ECF_RETURNS_TWICE.
592 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
593 space from the stack such as alloca. */
595 static int
596 special_function_p (const_tree fndecl, int flags)
598 tree name_decl = DECL_NAME (fndecl);
600 /* For instrumentation clones we want to derive flags
601 from the original name. */
602 if (cgraph_node::get (fndecl)
603 && cgraph_node::get (fndecl)->instrumentation_clone)
604 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
606 if (fndecl && name_decl
607 && IDENTIFIER_LENGTH (name_decl) <= 11
608 /* Exclude functions not at the file scope, or not `extern',
609 since they are not the magic functions we would otherwise
610 think they are.
611 FIXME: this should be handled with attributes, not with this
612 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
613 because you can declare fork() inside a function if you
614 wish. */
615 && (DECL_CONTEXT (fndecl) == NULL_TREE
616 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
617 && TREE_PUBLIC (fndecl))
619 const char *name = IDENTIFIER_POINTER (name_decl);
620 const char *tname = name;
622 /* We assume that alloca will always be called by name. It
623 makes no sense to pass it as a pointer-to-function to
624 anything that does not understand its behavior. */
625 if (IDENTIFIER_LENGTH (name_decl) == 6
626 && name[0] == 'a'
627 && ! strcmp (name, "alloca"))
628 flags |= ECF_MAY_BE_ALLOCA;
630 /* Disregard prefix _ or __. */
631 if (name[0] == '_')
633 if (name[1] == '_')
634 tname += 2;
635 else
636 tname += 1;
639 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
640 if (! strcmp (tname, "setjmp")
641 || ! strcmp (tname, "sigsetjmp")
642 || ! strcmp (name, "savectx")
643 || ! strcmp (name, "vfork")
644 || ! strcmp (name, "getcontext"))
645 flags |= ECF_RETURNS_TWICE;
648 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
649 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (fndecl)))
650 flags |= ECF_MAY_BE_ALLOCA;
652 return flags;
655 /* Similar to special_function_p; return a set of ERF_ flags for the
656 function FNDECL. */
657 static int
658 decl_return_flags (tree fndecl)
660 tree attr;
661 tree type = TREE_TYPE (fndecl);
662 if (!type)
663 return 0;
665 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
666 if (!attr)
667 return 0;
669 attr = TREE_VALUE (TREE_VALUE (attr));
670 if (!attr || TREE_STRING_LENGTH (attr) < 1)
671 return 0;
673 switch (TREE_STRING_POINTER (attr)[0])
675 case '1':
676 case '2':
677 case '3':
678 case '4':
679 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
681 case 'm':
682 return ERF_NOALIAS;
684 case '.':
685 default:
686 return 0;
690 /* Return nonzero when FNDECL represents a call to setjmp. */
693 setjmp_call_p (const_tree fndecl)
695 if (DECL_IS_RETURNS_TWICE (fndecl))
696 return ECF_RETURNS_TWICE;
697 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
701 /* Return true if STMT may be an alloca call. */
703 bool
704 gimple_maybe_alloca_call_p (const gimple *stmt)
706 tree fndecl;
708 if (!is_gimple_call (stmt))
709 return false;
711 fndecl = gimple_call_fndecl (stmt);
712 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
713 return true;
715 return false;
718 /* Return true if STMT is a builtin alloca call. */
720 bool
721 gimple_alloca_call_p (const gimple *stmt)
723 tree fndecl;
725 if (!is_gimple_call (stmt))
726 return false;
728 fndecl = gimple_call_fndecl (stmt);
729 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
730 switch (DECL_FUNCTION_CODE (fndecl))
732 CASE_BUILT_IN_ALLOCA:
733 return true;
734 default:
735 break;
738 return false;
741 /* Return true when exp contains a builtin alloca call. */
743 bool
744 alloca_call_p (const_tree exp)
746 tree fndecl;
747 if (TREE_CODE (exp) == CALL_EXPR
748 && (fndecl = get_callee_fndecl (exp))
749 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
750 switch (DECL_FUNCTION_CODE (fndecl))
752 CASE_BUILT_IN_ALLOCA:
753 return true;
754 default:
755 break;
758 return false;
761 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
762 function. Return FALSE otherwise. */
764 static bool
765 is_tm_builtin (const_tree fndecl)
767 if (fndecl == NULL)
768 return false;
770 if (decl_is_tm_clone (fndecl))
771 return true;
773 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
775 switch (DECL_FUNCTION_CODE (fndecl))
777 case BUILT_IN_TM_COMMIT:
778 case BUILT_IN_TM_COMMIT_EH:
779 case BUILT_IN_TM_ABORT:
780 case BUILT_IN_TM_IRREVOCABLE:
781 case BUILT_IN_TM_GETTMCLONE_IRR:
782 case BUILT_IN_TM_MEMCPY:
783 case BUILT_IN_TM_MEMMOVE:
784 case BUILT_IN_TM_MEMSET:
785 CASE_BUILT_IN_TM_STORE (1):
786 CASE_BUILT_IN_TM_STORE (2):
787 CASE_BUILT_IN_TM_STORE (4):
788 CASE_BUILT_IN_TM_STORE (8):
789 CASE_BUILT_IN_TM_STORE (FLOAT):
790 CASE_BUILT_IN_TM_STORE (DOUBLE):
791 CASE_BUILT_IN_TM_STORE (LDOUBLE):
792 CASE_BUILT_IN_TM_STORE (M64):
793 CASE_BUILT_IN_TM_STORE (M128):
794 CASE_BUILT_IN_TM_STORE (M256):
795 CASE_BUILT_IN_TM_LOAD (1):
796 CASE_BUILT_IN_TM_LOAD (2):
797 CASE_BUILT_IN_TM_LOAD (4):
798 CASE_BUILT_IN_TM_LOAD (8):
799 CASE_BUILT_IN_TM_LOAD (FLOAT):
800 CASE_BUILT_IN_TM_LOAD (DOUBLE):
801 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
802 CASE_BUILT_IN_TM_LOAD (M64):
803 CASE_BUILT_IN_TM_LOAD (M128):
804 CASE_BUILT_IN_TM_LOAD (M256):
805 case BUILT_IN_TM_LOG:
806 case BUILT_IN_TM_LOG_1:
807 case BUILT_IN_TM_LOG_2:
808 case BUILT_IN_TM_LOG_4:
809 case BUILT_IN_TM_LOG_8:
810 case BUILT_IN_TM_LOG_FLOAT:
811 case BUILT_IN_TM_LOG_DOUBLE:
812 case BUILT_IN_TM_LOG_LDOUBLE:
813 case BUILT_IN_TM_LOG_M64:
814 case BUILT_IN_TM_LOG_M128:
815 case BUILT_IN_TM_LOG_M256:
816 return true;
817 default:
818 break;
821 return false;
824 /* Detect flags (function attributes) from the function decl or type node. */
827 flags_from_decl_or_type (const_tree exp)
829 int flags = 0;
831 if (DECL_P (exp))
833 /* The function exp may have the `malloc' attribute. */
834 if (DECL_IS_MALLOC (exp))
835 flags |= ECF_MALLOC;
837 /* The function exp may have the `returns_twice' attribute. */
838 if (DECL_IS_RETURNS_TWICE (exp))
839 flags |= ECF_RETURNS_TWICE;
841 /* Process the pure and const attributes. */
842 if (TREE_READONLY (exp))
843 flags |= ECF_CONST;
844 if (DECL_PURE_P (exp))
845 flags |= ECF_PURE;
846 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
847 flags |= ECF_LOOPING_CONST_OR_PURE;
849 if (DECL_IS_NOVOPS (exp))
850 flags |= ECF_NOVOPS;
851 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
852 flags |= ECF_LEAF;
853 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
854 flags |= ECF_COLD;
856 if (TREE_NOTHROW (exp))
857 flags |= ECF_NOTHROW;
859 if (flag_tm)
861 if (is_tm_builtin (exp))
862 flags |= ECF_TM_BUILTIN;
863 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
864 || lookup_attribute ("transaction_pure",
865 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
866 flags |= ECF_TM_PURE;
869 flags = special_function_p (exp, flags);
871 else if (TYPE_P (exp))
873 if (TYPE_READONLY (exp))
874 flags |= ECF_CONST;
876 if (flag_tm
877 && ((flags & ECF_CONST) != 0
878 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
879 flags |= ECF_TM_PURE;
881 else
882 gcc_unreachable ();
884 if (TREE_THIS_VOLATILE (exp))
886 flags |= ECF_NORETURN;
887 if (flags & (ECF_CONST|ECF_PURE))
888 flags |= ECF_LOOPING_CONST_OR_PURE;
891 return flags;
894 /* Detect flags from a CALL_EXPR. */
897 call_expr_flags (const_tree t)
899 int flags;
900 tree decl = get_callee_fndecl (t);
902 if (decl)
903 flags = flags_from_decl_or_type (decl);
904 else if (CALL_EXPR_FN (t) == NULL_TREE)
905 flags = internal_fn_flags (CALL_EXPR_IFN (t));
906 else
908 tree type = TREE_TYPE (CALL_EXPR_FN (t));
909 if (type && TREE_CODE (type) == POINTER_TYPE)
910 flags = flags_from_decl_or_type (TREE_TYPE (type));
911 else
912 flags = 0;
913 if (CALL_EXPR_BY_DESCRIPTOR (t))
914 flags |= ECF_BY_DESCRIPTOR;
917 return flags;
920 /* Return true if TYPE should be passed by invisible reference. */
922 bool
923 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
924 tree type, bool named_arg)
926 if (type)
928 /* If this type contains non-trivial constructors, then it is
929 forbidden for the middle-end to create any new copies. */
930 if (TREE_ADDRESSABLE (type))
931 return true;
933 /* GCC post 3.4 passes *all* variable sized types by reference. */
934 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
935 return true;
937 /* If a record type should be passed the same as its first (and only)
938 member, use the type and mode of that member. */
939 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
941 type = TREE_TYPE (first_field (type));
942 mode = TYPE_MODE (type);
946 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
947 type, named_arg);
950 /* Return true if TYPE, which is passed by reference, should be callee
951 copied instead of caller copied. */
953 bool
954 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
955 tree type, bool named_arg)
957 if (type && TREE_ADDRESSABLE (type))
958 return false;
959 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
960 named_arg);
964 /* Precompute all register parameters as described by ARGS, storing values
965 into fields within the ARGS array.
967 NUM_ACTUALS indicates the total number elements in the ARGS array.
969 Set REG_PARM_SEEN if we encounter a register parameter. */
971 static void
972 precompute_register_parameters (int num_actuals, struct arg_data *args,
973 int *reg_parm_seen)
975 int i;
977 *reg_parm_seen = 0;
979 for (i = 0; i < num_actuals; i++)
980 if (args[i].reg != 0 && ! args[i].pass_on_stack)
982 *reg_parm_seen = 1;
984 if (args[i].value == 0)
986 push_temp_slots ();
987 args[i].value = expand_normal (args[i].tree_value);
988 preserve_temp_slots (args[i].value);
989 pop_temp_slots ();
992 /* If we are to promote the function arg to a wider mode,
993 do it now. */
995 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
996 args[i].value
997 = convert_modes (args[i].mode,
998 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
999 args[i].value, args[i].unsignedp);
1001 /* If the value is a non-legitimate constant, force it into a
1002 pseudo now. TLS symbols sometimes need a call to resolve. */
1003 if (CONSTANT_P (args[i].value)
1004 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
1005 args[i].value = force_reg (args[i].mode, args[i].value);
1007 /* If we're going to have to load the value by parts, pull the
1008 parts into pseudos. The part extraction process can involve
1009 non-trivial computation. */
1010 if (GET_CODE (args[i].reg) == PARALLEL)
1012 tree type = TREE_TYPE (args[i].tree_value);
1013 args[i].parallel_value
1014 = emit_group_load_into_temps (args[i].reg, args[i].value,
1015 type, int_size_in_bytes (type));
1018 /* If the value is expensive, and we are inside an appropriately
1019 short loop, put the value into a pseudo and then put the pseudo
1020 into the hard reg.
1022 For small register classes, also do this if this call uses
1023 register parameters. This is to avoid reload conflicts while
1024 loading the parameters registers. */
1026 else if ((! (REG_P (args[i].value)
1027 || (GET_CODE (args[i].value) == SUBREG
1028 && REG_P (SUBREG_REG (args[i].value)))))
1029 && args[i].mode != BLKmode
1030 && (set_src_cost (args[i].value, args[i].mode,
1031 optimize_insn_for_speed_p ())
1032 > COSTS_N_INSNS (1))
1033 && ((*reg_parm_seen
1034 && targetm.small_register_classes_for_mode_p (args[i].mode))
1035 || optimize))
1036 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1040 #ifdef REG_PARM_STACK_SPACE
1042 /* The argument list is the property of the called routine and it
1043 may clobber it. If the fixed area has been used for previous
1044 parameters, we must save and restore it. */
1046 static rtx
1047 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1049 unsigned int low;
1050 unsigned int high;
1052 /* Compute the boundary of the area that needs to be saved, if any. */
1053 high = reg_parm_stack_space;
1054 if (ARGS_GROW_DOWNWARD)
1055 high += 1;
1057 if (high > highest_outgoing_arg_in_use)
1058 high = highest_outgoing_arg_in_use;
1060 for (low = 0; low < high; low++)
1061 if (stack_usage_map[low] != 0 || low >= stack_usage_watermark)
1063 int num_to_save;
1064 machine_mode save_mode;
1065 int delta;
1066 rtx addr;
1067 rtx stack_area;
1068 rtx save_area;
1070 while (stack_usage_map[--high] == 0)
1073 *low_to_save = low;
1074 *high_to_save = high;
1076 num_to_save = high - low + 1;
1078 /* If we don't have the required alignment, must do this
1079 in BLKmode. */
1080 scalar_int_mode imode;
1081 if (int_mode_for_size (num_to_save * BITS_PER_UNIT, 1).exists (&imode)
1082 && (low & (MIN (GET_MODE_SIZE (imode),
1083 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)) == 0)
1084 save_mode = imode;
1085 else
1086 save_mode = BLKmode;
1088 if (ARGS_GROW_DOWNWARD)
1089 delta = -high;
1090 else
1091 delta = low;
1093 addr = plus_constant (Pmode, argblock, delta);
1094 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1096 set_mem_align (stack_area, PARM_BOUNDARY);
1097 if (save_mode == BLKmode)
1099 save_area = assign_stack_temp (BLKmode, num_to_save);
1100 emit_block_move (validize_mem (save_area), stack_area,
1101 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1103 else
1105 save_area = gen_reg_rtx (save_mode);
1106 emit_move_insn (save_area, stack_area);
1109 return save_area;
1112 return NULL_RTX;
1115 static void
1116 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1118 machine_mode save_mode = GET_MODE (save_area);
1119 int delta;
1120 rtx addr, stack_area;
1122 if (ARGS_GROW_DOWNWARD)
1123 delta = -high_to_save;
1124 else
1125 delta = low_to_save;
1127 addr = plus_constant (Pmode, argblock, delta);
1128 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1129 set_mem_align (stack_area, PARM_BOUNDARY);
1131 if (save_mode != BLKmode)
1132 emit_move_insn (stack_area, save_area);
1133 else
1134 emit_block_move (stack_area, validize_mem (save_area),
1135 GEN_INT (high_to_save - low_to_save + 1),
1136 BLOCK_OP_CALL_PARM);
1138 #endif /* REG_PARM_STACK_SPACE */
1140 /* If any elements in ARGS refer to parameters that are to be passed in
1141 registers, but not in memory, and whose alignment does not permit a
1142 direct copy into registers. Copy the values into a group of pseudos
1143 which we will later copy into the appropriate hard registers.
1145 Pseudos for each unaligned argument will be stored into the array
1146 args[argnum].aligned_regs. The caller is responsible for deallocating
1147 the aligned_regs array if it is nonzero. */
1149 static void
1150 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1152 int i, j;
1154 for (i = 0; i < num_actuals; i++)
1155 if (args[i].reg != 0 && ! args[i].pass_on_stack
1156 && GET_CODE (args[i].reg) != PARALLEL
1157 && args[i].mode == BLKmode
1158 && MEM_P (args[i].value)
1159 && (MEM_ALIGN (args[i].value)
1160 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1162 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1163 int endian_correction = 0;
1165 if (args[i].partial)
1167 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1168 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1170 else
1172 args[i].n_aligned_regs
1173 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1176 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1178 /* Structures smaller than a word are normally aligned to the
1179 least significant byte. On a BYTES_BIG_ENDIAN machine,
1180 this means we must skip the empty high order bytes when
1181 calculating the bit offset. */
1182 if (bytes < UNITS_PER_WORD
1183 #ifdef BLOCK_REG_PADDING
1184 && (BLOCK_REG_PADDING (args[i].mode,
1185 TREE_TYPE (args[i].tree_value), 1)
1186 == PAD_DOWNWARD)
1187 #else
1188 && BYTES_BIG_ENDIAN
1189 #endif
1191 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1193 for (j = 0; j < args[i].n_aligned_regs; j++)
1195 rtx reg = gen_reg_rtx (word_mode);
1196 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1197 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1199 args[i].aligned_regs[j] = reg;
1200 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1201 word_mode, word_mode, false, NULL);
1203 /* There is no need to restrict this code to loading items
1204 in TYPE_ALIGN sized hunks. The bitfield instructions can
1205 load up entire word sized registers efficiently.
1207 ??? This may not be needed anymore.
1208 We use to emit a clobber here but that doesn't let later
1209 passes optimize the instructions we emit. By storing 0 into
1210 the register later passes know the first AND to zero out the
1211 bitfield being set in the register is unnecessary. The store
1212 of 0 will be deleted as will at least the first AND. */
1214 emit_move_insn (reg, const0_rtx);
1216 bytes -= bitsize / BITS_PER_UNIT;
1217 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1218 word_mode, word, false);
1223 /* The limit set by -Walloc-larger-than=. */
1224 static GTY(()) tree alloc_object_size_limit;
1226 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1227 setting if the option is specified, or to the maximum object size if it
1228 is not. Return the initialized value. */
1230 static tree
1231 alloc_max_size (void)
1233 if (!alloc_object_size_limit)
1235 alloc_object_size_limit = max_object_size ();
1237 if (warn_alloc_size_limit)
1239 char *end = NULL;
1240 errno = 0;
1241 unsigned HOST_WIDE_INT unit = 1;
1242 unsigned HOST_WIDE_INT limit
1243 = strtoull (warn_alloc_size_limit, &end, 10);
1245 if (!errno)
1247 if (end && *end)
1249 /* Numeric option arguments are at most INT_MAX. Make it
1250 possible to specify a larger value by accepting common
1251 suffixes. */
1252 if (!strcmp (end, "kB"))
1253 unit = 1000;
1254 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1255 unit = 1024;
1256 else if (!strcmp (end, "MB"))
1257 unit = HOST_WIDE_INT_UC (1000) * 1000;
1258 else if (!strcasecmp (end, "MiB"))
1259 unit = HOST_WIDE_INT_UC (1024) * 1024;
1260 else if (!strcasecmp (end, "GB"))
1261 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000;
1262 else if (!strcasecmp (end, "GiB"))
1263 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024;
1264 else if (!strcasecmp (end, "TB"))
1265 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000;
1266 else if (!strcasecmp (end, "TiB"))
1267 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024;
1268 else if (!strcasecmp (end, "PB"))
1269 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000;
1270 else if (!strcasecmp (end, "PiB"))
1271 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024;
1272 else if (!strcasecmp (end, "EB"))
1273 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000
1274 * 1000;
1275 else if (!strcasecmp (end, "EiB"))
1276 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024
1277 * 1024;
1278 else
1279 unit = 0;
1282 if (unit)
1284 widest_int w = wi::mul (limit, unit);
1285 if (w < wi::to_widest (alloc_object_size_limit))
1286 alloc_object_size_limit
1287 = wide_int_to_tree (ptrdiff_type_node, w);
1292 return alloc_object_size_limit;
1295 /* Return true when EXP's range can be determined and set RANGE[] to it
1296 after adjusting it if necessary to make EXP a represents a valid size
1297 of object, or a valid size argument to an allocation function declared
1298 with attribute alloc_size (whose argument may be signed), or to a string
1299 manipulation function like memset. When ALLOW_ZERO is true, allow
1300 returning a range of [0, 0] for a size in an anti-range [1, N] where
1301 N > PTRDIFF_MAX. A zero range is a (nearly) invalid argument to
1302 allocation functions like malloc but it is a valid argument to
1303 functions like memset. */
1305 bool
1306 get_size_range (tree exp, tree range[2], bool allow_zero /* = false */)
1308 if (tree_fits_uhwi_p (exp))
1310 /* EXP is a constant. */
1311 range[0] = range[1] = exp;
1312 return true;
1315 tree exptype = TREE_TYPE (exp);
1316 bool integral = INTEGRAL_TYPE_P (exptype);
1318 wide_int min, max;
1319 enum value_range_type range_type;
1321 if (TREE_CODE (exp) == SSA_NAME && integral)
1322 range_type = get_range_info (exp, &min, &max);
1323 else
1324 range_type = VR_VARYING;
1326 if (range_type == VR_VARYING)
1328 if (integral)
1330 /* Use the full range of the type of the expression when
1331 no value range information is available. */
1332 range[0] = TYPE_MIN_VALUE (exptype);
1333 range[1] = TYPE_MAX_VALUE (exptype);
1334 return true;
1337 range[0] = NULL_TREE;
1338 range[1] = NULL_TREE;
1339 return false;
1342 unsigned expprec = TYPE_PRECISION (exptype);
1344 bool signed_p = !TYPE_UNSIGNED (exptype);
1346 if (range_type == VR_ANTI_RANGE)
1348 if (signed_p)
1350 if (wi::les_p (max, 0))
1352 /* EXP is not in a strictly negative range. That means
1353 it must be in some (not necessarily strictly) positive
1354 range which includes zero. Since in signed to unsigned
1355 conversions negative values end up converted to large
1356 positive values, and otherwise they are not valid sizes,
1357 the resulting range is in both cases [0, TYPE_MAX]. */
1358 min = wi::zero (expprec);
1359 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1361 else if (wi::les_p (min - 1, 0))
1363 /* EXP is not in a negative-positive range. That means EXP
1364 is either negative, or greater than max. Since negative
1365 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1366 min = max + 1;
1367 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1369 else
1371 max = min - 1;
1372 min = wi::zero (expprec);
1375 else if (wi::eq_p (0, min - 1))
1377 /* EXP is unsigned and not in the range [1, MAX]. That means
1378 it's either zero or greater than MAX. Even though 0 would
1379 normally be detected by -Walloc-zero, unless ALLOW_ZERO
1380 is true, set the range to [MAX, TYPE_MAX] so that when MAX
1381 is greater than the limit the whole range is diagnosed. */
1382 if (allow_zero)
1383 min = max = wi::zero (expprec);
1384 else
1386 min = max + 1;
1387 max = wi::to_wide (TYPE_MAX_VALUE (exptype));
1390 else
1392 max = min - 1;
1393 min = wi::zero (expprec);
1397 range[0] = wide_int_to_tree (exptype, min);
1398 range[1] = wide_int_to_tree (exptype, max);
1400 return true;
1403 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1404 whose argument numbers given by IDX with values given by ARGS exceed
1405 the maximum object size or cause an unsigned oveflow (wrapping) when
1406 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1407 may be null for functions like malloc, and non-null for those like
1408 calloc that are decorated with a two-argument attribute alloc_size. */
1410 void
1411 maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1413 /* The range each of the (up to) two arguments is known to be in. */
1414 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1416 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1417 tree maxobjsize = alloc_max_size ();
1419 location_t loc = EXPR_LOCATION (exp);
1421 bool warned = false;
1423 /* Validate each argument individually. */
1424 for (unsigned i = 0; i != 2 && args[i]; ++i)
1426 if (TREE_CODE (args[i]) == INTEGER_CST)
1428 argrange[i][0] = args[i];
1429 argrange[i][1] = args[i];
1431 if (tree_int_cst_lt (args[i], integer_zero_node))
1433 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1434 "%Kargument %i value %qE is negative",
1435 exp, idx[i] + 1, args[i]);
1437 else if (integer_zerop (args[i]))
1439 /* Avoid issuing -Walloc-zero for allocation functions other
1440 than __builtin_alloca that are declared with attribute
1441 returns_nonnull because there's no portability risk. This
1442 avoids warning for such calls to libiberty's xmalloc and
1443 friends.
1444 Also avoid issuing the warning for calls to function named
1445 "alloca". */
1446 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1447 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1448 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1449 && !lookup_attribute ("returns_nonnull",
1450 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1451 warned = warning_at (loc, OPT_Walloc_zero,
1452 "%Kargument %i value is zero",
1453 exp, idx[i] + 1);
1455 else if (tree_int_cst_lt (maxobjsize, args[i]))
1457 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1458 mode and with -fno-exceptions as a way to indicate array
1459 size overflow. There's no good way to detect C++98 here
1460 so avoid diagnosing these calls for all C++ modes. */
1461 if (i == 0
1462 && !args[1]
1463 && lang_GNU_CXX ()
1464 && DECL_IS_OPERATOR_NEW (fn)
1465 && integer_all_onesp (args[i]))
1466 continue;
1468 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1469 "%Kargument %i value %qE exceeds "
1470 "maximum object size %E",
1471 exp, idx[i] + 1, args[i], maxobjsize);
1474 else if (TREE_CODE (args[i]) == SSA_NAME
1475 && get_size_range (args[i], argrange[i]))
1477 /* Verify that the argument's range is not negative (including
1478 upper bound of zero). */
1479 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1480 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1482 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1483 "%Kargument %i range [%E, %E] is negative",
1484 exp, idx[i] + 1,
1485 argrange[i][0], argrange[i][1]);
1487 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1489 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1490 "%Kargument %i range [%E, %E] exceeds "
1491 "maximum object size %E",
1492 exp, idx[i] + 1,
1493 argrange[i][0], argrange[i][1],
1494 maxobjsize);
1499 if (!argrange[0])
1500 return;
1502 /* For a two-argument alloc_size, validate the product of the two
1503 arguments if both of their values or ranges are known. */
1504 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1505 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1506 && !integer_onep (argrange[0][0])
1507 && !integer_onep (argrange[1][0]))
1509 /* Check for overflow in the product of a function decorated with
1510 attribute alloc_size (X, Y). */
1511 unsigned szprec = TYPE_PRECISION (size_type_node);
1512 wide_int x = wi::to_wide (argrange[0][0], szprec);
1513 wide_int y = wi::to_wide (argrange[1][0], szprec);
1515 bool vflow;
1516 wide_int prod = wi::umul (x, y, &vflow);
1518 if (vflow)
1519 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1520 "%Kproduct %<%E * %E%> of arguments %i and %i "
1521 "exceeds %<SIZE_MAX%>",
1522 exp, argrange[0][0], argrange[1][0],
1523 idx[0] + 1, idx[1] + 1);
1524 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1525 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1526 "%Kproduct %<%E * %E%> of arguments %i and %i "
1527 "exceeds maximum object size %E",
1528 exp, argrange[0][0], argrange[1][0],
1529 idx[0] + 1, idx[1] + 1,
1530 maxobjsize);
1532 if (warned)
1534 /* Print the full range of each of the two arguments to make
1535 it clear when it is, in fact, in a range and not constant. */
1536 if (argrange[0][0] != argrange [0][1])
1537 inform (loc, "argument %i in the range [%E, %E]",
1538 idx[0] + 1, argrange[0][0], argrange[0][1]);
1539 if (argrange[1][0] != argrange [1][1])
1540 inform (loc, "argument %i in the range [%E, %E]",
1541 idx[1] + 1, argrange[1][0], argrange[1][1]);
1545 if (warned)
1547 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1549 if (DECL_IS_BUILTIN (fn))
1550 inform (loc,
1551 "in a call to built-in allocation function %qD", fn);
1552 else
1553 inform (fnloc,
1554 "in a call to allocation function %qD declared here", fn);
1558 /* If EXPR refers to a character array or pointer declared attribute
1559 nonstring return a decl for that array or pointer and set *REF to
1560 the referenced enclosing object or pointer. Otherwise returns
1561 null. */
1563 tree
1564 get_attr_nonstring_decl (tree expr, tree *ref)
1566 tree decl = expr;
1567 if (TREE_CODE (decl) == SSA_NAME)
1569 gimple *def = SSA_NAME_DEF_STMT (decl);
1571 if (is_gimple_assign (def))
1573 tree_code code = gimple_assign_rhs_code (def);
1574 if (code == ADDR_EXPR
1575 || code == COMPONENT_REF
1576 || code == VAR_DECL)
1577 decl = gimple_assign_rhs1 (def);
1579 else if (tree var = SSA_NAME_VAR (decl))
1580 decl = var;
1583 if (TREE_CODE (decl) == ADDR_EXPR)
1584 decl = TREE_OPERAND (decl, 0);
1586 if (ref)
1587 *ref = decl;
1589 if (TREE_CODE (decl) == COMPONENT_REF)
1590 decl = TREE_OPERAND (decl, 1);
1592 if (DECL_P (decl)
1593 && lookup_attribute ("nonstring", DECL_ATTRIBUTES (decl)))
1594 return decl;
1596 return NULL_TREE;
1599 /* Warn about passing a non-string array/pointer to a function that
1600 expects a nul-terminated string argument. */
1602 void
1603 maybe_warn_nonstring_arg (tree fndecl, tree exp)
1605 if (!fndecl || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
1606 return;
1608 bool with_bounds = CALL_WITH_BOUNDS_P (exp);
1610 unsigned nargs = call_expr_nargs (exp);
1612 /* The bound argument to a bounded string function like strncpy. */
1613 tree bound = NULL_TREE;
1615 /* It's safe to call "bounded" string functions with a non-string
1616 argument since the functions provide an explicit bound for this
1617 purpose. */
1618 switch (DECL_FUNCTION_CODE (fndecl))
1620 case BUILT_IN_STPNCPY:
1621 case BUILT_IN_STPNCPY_CHK:
1622 case BUILT_IN_STRNCMP:
1623 case BUILT_IN_STRNCASECMP:
1624 case BUILT_IN_STRNCPY:
1625 case BUILT_IN_STRNCPY_CHK:
1627 unsigned argno = with_bounds ? 4 : 2;
1628 if (argno < nargs)
1629 bound = CALL_EXPR_ARG (exp, argno);
1630 break;
1633 case BUILT_IN_STRNDUP:
1635 unsigned argno = with_bounds ? 2 : 1;
1636 if (argno < nargs)
1637 bound = CALL_EXPR_ARG (exp, argno);
1638 break;
1641 default:
1642 break;
1645 /* Determine the range of the bound argument (if specified). */
1646 tree bndrng[2] = { NULL_TREE, NULL_TREE };
1647 if (bound)
1648 get_size_range (bound, bndrng);
1650 /* Iterate over the built-in function's formal arguments and check
1651 each const char* against the actual argument. If the actual
1652 argument is declared attribute non-string issue a warning unless
1653 the argument's maximum length is bounded. */
1654 function_args_iterator it;
1655 function_args_iter_init (&it, TREE_TYPE (fndecl));
1657 for (unsigned argno = 0; ; ++argno, function_args_iter_next (&it))
1659 /* Avoid iterating past the declared argument in a call
1660 to function declared without a prototype. */
1661 if (argno >= nargs)
1662 break;
1664 tree argtype = function_args_iter_cond (&it);
1665 if (!argtype)
1666 break;
1668 if (TREE_CODE (argtype) != POINTER_TYPE)
1669 continue;
1671 argtype = TREE_TYPE (argtype);
1673 if (TREE_CODE (argtype) != INTEGER_TYPE
1674 || !TYPE_READONLY (argtype))
1675 continue;
1677 argtype = TYPE_MAIN_VARIANT (argtype);
1678 if (argtype != char_type_node)
1679 continue;
1681 tree callarg = CALL_EXPR_ARG (exp, argno);
1682 if (TREE_CODE (callarg) == ADDR_EXPR)
1683 callarg = TREE_OPERAND (callarg, 0);
1685 /* See if the destination is declared with attribute "nonstring". */
1686 tree decl = get_attr_nonstring_decl (callarg);
1687 if (!decl)
1688 continue;
1690 tree type = TREE_TYPE (decl);
1692 offset_int wibnd = 0;
1693 if (bndrng[0])
1694 wibnd = wi::to_offset (bndrng[0]);
1696 offset_int asize = wibnd;
1698 if (TREE_CODE (type) == ARRAY_TYPE)
1699 if (tree arrbnd = TYPE_DOMAIN (type))
1701 if ((arrbnd = TYPE_MAX_VALUE (arrbnd)))
1702 asize = wi::to_offset (arrbnd) + 1;
1705 location_t loc = EXPR_LOCATION (exp);
1707 bool warned = false;
1709 if (wi::ltu_p (asize, wibnd))
1710 warned = warning_at (loc, OPT_Wstringop_overflow_,
1711 "%qD argument %i declared attribute %<nonstring%> "
1712 "is smaller than the specified bound %E",
1713 fndecl, argno + 1, bndrng[0]);
1714 else if (!bound)
1715 warned = warning_at (loc, OPT_Wstringop_overflow_,
1716 "%qD argument %i declared attribute %<nonstring%>",
1717 fndecl, argno + 1);
1719 if (warned)
1720 inform (DECL_SOURCE_LOCATION (decl),
1721 "argument %qD declared here", decl);
1725 /* Issue an error if CALL_EXPR was flagged as requiring
1726 tall-call optimization. */
1728 static void
1729 maybe_complain_about_tail_call (tree call_expr, const char *reason)
1731 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1732 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1733 return;
1735 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1738 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1739 CALL_EXPR EXP.
1741 NUM_ACTUALS is the total number of parameters.
1743 N_NAMED_ARGS is the total number of named arguments.
1745 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1746 value, or null.
1748 FNDECL is the tree code for the target of this call (if known)
1750 ARGS_SO_FAR holds state needed by the target to know where to place
1751 the next argument.
1753 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1754 for arguments which are passed in registers.
1756 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1757 and may be modified by this routine.
1759 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1760 flags which may be modified by this routine.
1762 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1763 that requires allocation of stack space.
1765 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1766 the thunked-to function. */
1768 static void
1769 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1770 struct arg_data *args,
1771 struct args_size *args_size,
1772 int n_named_args ATTRIBUTE_UNUSED,
1773 tree exp, tree struct_value_addr_value,
1774 tree fndecl, tree fntype,
1775 cumulative_args_t args_so_far,
1776 int reg_parm_stack_space,
1777 rtx *old_stack_level,
1778 poly_int64_pod *old_pending_adj,
1779 int *must_preallocate, int *ecf_flags,
1780 bool *may_tailcall, bool call_from_thunk_p)
1782 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1783 location_t loc = EXPR_LOCATION (exp);
1785 /* Count arg position in order args appear. */
1786 int argpos;
1788 int i;
1790 args_size->constant = 0;
1791 args_size->var = 0;
1793 bitmap_obstack_initialize (NULL);
1795 /* In this loop, we consider args in the order they are written.
1796 We fill up ARGS from the back. */
1798 i = num_actuals - 1;
1800 int j = i, ptr_arg = -1;
1801 call_expr_arg_iterator iter;
1802 tree arg;
1803 bitmap slots = NULL;
1805 if (struct_value_addr_value)
1807 args[j].tree_value = struct_value_addr_value;
1808 j--;
1810 /* If we pass structure address then we need to
1811 create bounds for it. Since created bounds is
1812 a call statement, we expand it right here to avoid
1813 fixing all other places where it may be expanded. */
1814 if (CALL_WITH_BOUNDS_P (exp))
1816 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1817 args[j].tree_value
1818 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1819 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1820 EXPAND_NORMAL, 0, false);
1821 args[j].pointer_arg = j + 1;
1822 j--;
1825 argpos = 0;
1826 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1828 tree argtype = TREE_TYPE (arg);
1830 /* Remember last param with pointer and associate it
1831 with following pointer bounds. */
1832 if (CALL_WITH_BOUNDS_P (exp)
1833 && chkp_type_has_pointer (argtype))
1835 if (slots)
1836 BITMAP_FREE (slots);
1837 ptr_arg = j;
1838 if (!BOUNDED_TYPE_P (argtype))
1840 slots = BITMAP_ALLOC (NULL);
1841 chkp_find_bound_slots (argtype, slots);
1844 else if (CALL_WITH_BOUNDS_P (exp)
1845 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1846 argpos < n_named_args))
1848 if (slots)
1849 BITMAP_FREE (slots);
1850 ptr_arg = j;
1852 else if (POINTER_BOUNDS_TYPE_P (argtype))
1854 /* We expect bounds in instrumented calls only.
1855 Otherwise it is a sign we lost flag due to some optimization
1856 and may emit call args incorrectly. */
1857 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1859 /* For structures look for the next available pointer. */
1860 if (ptr_arg != -1 && slots)
1862 unsigned bnd_no = bitmap_first_set_bit (slots);
1863 args[j].pointer_offset =
1864 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1866 bitmap_clear_bit (slots, bnd_no);
1868 /* Check we have no more pointers in the structure. */
1869 if (bitmap_empty_p (slots))
1870 BITMAP_FREE (slots);
1872 args[j].pointer_arg = ptr_arg;
1874 /* Check we covered all pointers in the previous
1875 non bounds arg. */
1876 if (!slots)
1877 ptr_arg = -1;
1879 else
1880 ptr_arg = -1;
1882 if (targetm.calls.split_complex_arg
1883 && argtype
1884 && TREE_CODE (argtype) == COMPLEX_TYPE
1885 && targetm.calls.split_complex_arg (argtype))
1887 tree subtype = TREE_TYPE (argtype);
1888 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1889 j--;
1890 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1892 else
1893 args[j].tree_value = arg;
1894 j--;
1895 argpos++;
1898 if (slots)
1899 BITMAP_FREE (slots);
1902 bitmap_obstack_release (NULL);
1904 /* Extract attribute alloc_size and if set, store the indices of
1905 the corresponding arguments in ALLOC_IDX, and then the actual
1906 argument(s) at those indices in ALLOC_ARGS. */
1907 int alloc_idx[2] = { -1, -1 };
1908 if (tree alloc_size
1909 = (fndecl ? lookup_attribute ("alloc_size",
1910 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1911 : NULL_TREE))
1913 tree args = TREE_VALUE (alloc_size);
1914 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1915 if (TREE_CHAIN (args))
1916 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1919 /* Array for up to the two attribute alloc_size arguments. */
1920 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1922 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1923 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1925 tree type = TREE_TYPE (args[i].tree_value);
1926 int unsignedp;
1927 machine_mode mode;
1929 /* Replace erroneous argument with constant zero. */
1930 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1931 args[i].tree_value = integer_zero_node, type = integer_type_node;
1933 /* If TYPE is a transparent union or record, pass things the way
1934 we would pass the first field of the union or record. We have
1935 already verified that the modes are the same. */
1936 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1937 && TYPE_TRANSPARENT_AGGR (type))
1938 type = TREE_TYPE (first_field (type));
1940 /* Decide where to pass this arg.
1942 args[i].reg is nonzero if all or part is passed in registers.
1944 args[i].partial is nonzero if part but not all is passed in registers,
1945 and the exact value says how many bytes are passed in registers.
1947 args[i].pass_on_stack is nonzero if the argument must at least be
1948 computed on the stack. It may then be loaded back into registers
1949 if args[i].reg is nonzero.
1951 These decisions are driven by the FUNCTION_... macros and must agree
1952 with those made by function.c. */
1954 /* See if this argument should be passed by invisible reference. */
1955 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1956 type, argpos < n_named_args))
1958 bool callee_copies;
1959 tree base = NULL_TREE;
1961 callee_copies
1962 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1963 type, argpos < n_named_args);
1965 /* If we're compiling a thunk, pass through invisible references
1966 instead of making a copy. */
1967 if (call_from_thunk_p
1968 || (callee_copies
1969 && !TREE_ADDRESSABLE (type)
1970 && (base = get_base_address (args[i].tree_value))
1971 && TREE_CODE (base) != SSA_NAME
1972 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1974 /* We may have turned the parameter value into an SSA name.
1975 Go back to the original parameter so we can take the
1976 address. */
1977 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1979 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1980 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1981 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1983 /* Argument setup code may have copied the value to register. We
1984 revert that optimization now because the tail call code must
1985 use the original location. */
1986 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1987 && !MEM_P (DECL_RTL (args[i].tree_value))
1988 && DECL_INCOMING_RTL (args[i].tree_value)
1989 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1990 set_decl_rtl (args[i].tree_value,
1991 DECL_INCOMING_RTL (args[i].tree_value));
1993 mark_addressable (args[i].tree_value);
1995 /* We can't use sibcalls if a callee-copied argument is
1996 stored in the current function's frame. */
1997 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1999 *may_tailcall = false;
2000 maybe_complain_about_tail_call (exp,
2001 "a callee-copied argument is"
2002 " stored in the current "
2003 " function's frame");
2006 args[i].tree_value = build_fold_addr_expr_loc (loc,
2007 args[i].tree_value);
2008 type = TREE_TYPE (args[i].tree_value);
2010 if (*ecf_flags & ECF_CONST)
2011 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
2013 else
2015 /* We make a copy of the object and pass the address to the
2016 function being called. */
2017 rtx copy;
2019 if (!COMPLETE_TYPE_P (type)
2020 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
2021 || (flag_stack_check == GENERIC_STACK_CHECK
2022 && compare_tree_int (TYPE_SIZE_UNIT (type),
2023 STACK_CHECK_MAX_VAR_SIZE) > 0))
2025 /* This is a variable-sized object. Make space on the stack
2026 for it. */
2027 rtx size_rtx = expr_size (args[i].tree_value);
2029 if (*old_stack_level == 0)
2031 emit_stack_save (SAVE_BLOCK, old_stack_level);
2032 *old_pending_adj = pending_stack_adjust;
2033 pending_stack_adjust = 0;
2036 /* We can pass TRUE as the 4th argument because we just
2037 saved the stack pointer and will restore it right after
2038 the call. */
2039 copy = allocate_dynamic_stack_space (size_rtx,
2040 TYPE_ALIGN (type),
2041 TYPE_ALIGN (type),
2042 max_int_size_in_bytes
2043 (type),
2044 true);
2045 copy = gen_rtx_MEM (BLKmode, copy);
2046 set_mem_attributes (copy, type, 1);
2048 else
2049 copy = assign_temp (type, 1, 0);
2051 store_expr (args[i].tree_value, copy, 0, false, false);
2053 /* Just change the const function to pure and then let
2054 the next test clear the pure based on
2055 callee_copies. */
2056 if (*ecf_flags & ECF_CONST)
2058 *ecf_flags &= ~ECF_CONST;
2059 *ecf_flags |= ECF_PURE;
2062 if (!callee_copies && *ecf_flags & ECF_PURE)
2063 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2065 args[i].tree_value
2066 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
2067 type = TREE_TYPE (args[i].tree_value);
2068 *may_tailcall = false;
2069 maybe_complain_about_tail_call (exp,
2070 "argument must be passed"
2071 " by copying");
2075 unsignedp = TYPE_UNSIGNED (type);
2076 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
2077 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
2079 args[i].unsignedp = unsignedp;
2080 args[i].mode = mode;
2082 targetm.calls.warn_parameter_passing_abi (args_so_far, type);
2084 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
2085 argpos < n_named_args);
2087 if (args[i].reg && CONST_INT_P (args[i].reg))
2089 args[i].special_slot = args[i].reg;
2090 args[i].reg = NULL;
2093 /* If this is a sibling call and the machine has register windows, the
2094 register window has to be unwinded before calling the routine, so
2095 arguments have to go into the incoming registers. */
2096 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
2097 args[i].tail_call_reg
2098 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
2099 argpos < n_named_args);
2100 else
2101 args[i].tail_call_reg = args[i].reg;
2103 if (args[i].reg)
2104 args[i].partial
2105 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
2106 argpos < n_named_args);
2108 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
2110 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
2111 it means that we are to pass this arg in the register(s) designated
2112 by the PARALLEL, but also to pass it in the stack. */
2113 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
2114 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
2115 args[i].pass_on_stack = 1;
2117 /* If this is an addressable type, we must preallocate the stack
2118 since we must evaluate the object into its final location.
2120 If this is to be passed in both registers and the stack, it is simpler
2121 to preallocate. */
2122 if (TREE_ADDRESSABLE (type)
2123 || (args[i].pass_on_stack && args[i].reg != 0))
2124 *must_preallocate = 1;
2126 /* No stack allocation and padding for bounds. */
2127 if (POINTER_BOUNDS_P (args[i].tree_value))
2129 /* Compute the stack-size of this argument. */
2130 else if (args[i].reg == 0 || args[i].partial != 0
2131 || reg_parm_stack_space > 0
2132 || args[i].pass_on_stack)
2133 locate_and_pad_parm (mode, type,
2134 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2136 #else
2137 args[i].reg != 0,
2138 #endif
2139 reg_parm_stack_space,
2140 args[i].pass_on_stack ? 0 : args[i].partial,
2141 fndecl, args_size, &args[i].locate);
2142 #ifdef BLOCK_REG_PADDING
2143 else
2144 /* The argument is passed entirely in registers. See at which
2145 end it should be padded. */
2146 args[i].locate.where_pad =
2147 BLOCK_REG_PADDING (mode, type,
2148 int_size_in_bytes (type) <= UNITS_PER_WORD);
2149 #endif
2151 /* Update ARGS_SIZE, the total stack space for args so far. */
2153 args_size->constant += args[i].locate.size.constant;
2154 if (args[i].locate.size.var)
2155 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
2157 /* Increment ARGS_SO_FAR, which has info about which arg-registers
2158 have been used, etc. */
2160 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
2161 type, argpos < n_named_args);
2163 /* Store argument values for functions decorated with attribute
2164 alloc_size. */
2165 if (argpos == alloc_idx[0])
2166 alloc_args[0] = args[i].tree_value;
2167 else if (argpos == alloc_idx[1])
2168 alloc_args[1] = args[i].tree_value;
2171 if (alloc_args[0])
2173 /* Check the arguments of functions decorated with attribute
2174 alloc_size. */
2175 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
2178 /* Detect passing non-string arguments to functions expecting
2179 nul-terminated strings. */
2180 maybe_warn_nonstring_arg (fndecl, exp);
2183 /* Update ARGS_SIZE to contain the total size for the argument block.
2184 Return the original constant component of the argument block's size.
2186 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
2187 for arguments passed in registers. */
2189 static poly_int64
2190 compute_argument_block_size (int reg_parm_stack_space,
2191 struct args_size *args_size,
2192 tree fndecl ATTRIBUTE_UNUSED,
2193 tree fntype ATTRIBUTE_UNUSED,
2194 int preferred_stack_boundary ATTRIBUTE_UNUSED)
2196 poly_int64 unadjusted_args_size = args_size->constant;
2198 /* For accumulate outgoing args mode we don't need to align, since the frame
2199 will be already aligned. Align to STACK_BOUNDARY in order to prevent
2200 backends from generating misaligned frame sizes. */
2201 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
2202 preferred_stack_boundary = STACK_BOUNDARY;
2204 /* Compute the actual size of the argument block required. The variable
2205 and constant sizes must be combined, the size may have to be rounded,
2206 and there may be a minimum required size. */
2208 if (args_size->var)
2210 args_size->var = ARGS_SIZE_TREE (*args_size);
2211 args_size->constant = 0;
2213 preferred_stack_boundary /= BITS_PER_UNIT;
2214 if (preferred_stack_boundary > 1)
2216 /* We don't handle this case yet. To handle it correctly we have
2217 to add the delta, round and subtract the delta.
2218 Currently no machine description requires this support. */
2219 gcc_assert (multiple_p (stack_pointer_delta,
2220 preferred_stack_boundary));
2221 args_size->var = round_up (args_size->var, preferred_stack_boundary);
2224 if (reg_parm_stack_space > 0)
2226 args_size->var
2227 = size_binop (MAX_EXPR, args_size->var,
2228 ssize_int (reg_parm_stack_space));
2230 /* The area corresponding to register parameters is not to count in
2231 the size of the block we need. So make the adjustment. */
2232 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2233 args_size->var
2234 = size_binop (MINUS_EXPR, args_size->var,
2235 ssize_int (reg_parm_stack_space));
2238 else
2240 preferred_stack_boundary /= BITS_PER_UNIT;
2241 if (preferred_stack_boundary < 1)
2242 preferred_stack_boundary = 1;
2243 args_size->constant = (aligned_upper_bound (args_size->constant
2244 + stack_pointer_delta,
2245 preferred_stack_boundary)
2246 - stack_pointer_delta);
2248 args_size->constant = upper_bound (args_size->constant,
2249 reg_parm_stack_space);
2251 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2252 args_size->constant -= reg_parm_stack_space;
2254 return unadjusted_args_size;
2257 /* Precompute parameters as needed for a function call.
2259 FLAGS is mask of ECF_* constants.
2261 NUM_ACTUALS is the number of arguments.
2263 ARGS is an array containing information for each argument; this
2264 routine fills in the INITIAL_VALUE and VALUE fields for each
2265 precomputed argument. */
2267 static void
2268 precompute_arguments (int num_actuals, struct arg_data *args)
2270 int i;
2272 /* If this is a libcall, then precompute all arguments so that we do not
2273 get extraneous instructions emitted as part of the libcall sequence. */
2275 /* If we preallocated the stack space, and some arguments must be passed
2276 on the stack, then we must precompute any parameter which contains a
2277 function call which will store arguments on the stack.
2278 Otherwise, evaluating the parameter may clobber previous parameters
2279 which have already been stored into the stack. (we have code to avoid
2280 such case by saving the outgoing stack arguments, but it results in
2281 worse code) */
2282 if (!ACCUMULATE_OUTGOING_ARGS)
2283 return;
2285 for (i = 0; i < num_actuals; i++)
2287 tree type;
2288 machine_mode mode;
2290 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2291 continue;
2293 /* If this is an addressable type, we cannot pre-evaluate it. */
2294 type = TREE_TYPE (args[i].tree_value);
2295 gcc_assert (!TREE_ADDRESSABLE (type));
2297 args[i].initial_value = args[i].value
2298 = expand_normal (args[i].tree_value);
2300 mode = TYPE_MODE (type);
2301 if (mode != args[i].mode)
2303 int unsignedp = args[i].unsignedp;
2304 args[i].value
2305 = convert_modes (args[i].mode, mode,
2306 args[i].value, args[i].unsignedp);
2308 /* CSE will replace this only if it contains args[i].value
2309 pseudo, so convert it down to the declared mode using
2310 a SUBREG. */
2311 if (REG_P (args[i].value)
2312 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2313 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2315 args[i].initial_value
2316 = gen_lowpart_SUBREG (mode, args[i].value);
2317 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2318 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2324 /* Given the current state of MUST_PREALLOCATE and information about
2325 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2326 compute and return the final value for MUST_PREALLOCATE. */
2328 static int
2329 finalize_must_preallocate (int must_preallocate, int num_actuals,
2330 struct arg_data *args, struct args_size *args_size)
2332 /* See if we have or want to preallocate stack space.
2334 If we would have to push a partially-in-regs parm
2335 before other stack parms, preallocate stack space instead.
2337 If the size of some parm is not a multiple of the required stack
2338 alignment, we must preallocate.
2340 If the total size of arguments that would otherwise create a copy in
2341 a temporary (such as a CALL) is more than half the total argument list
2342 size, preallocation is faster.
2344 Another reason to preallocate is if we have a machine (like the m88k)
2345 where stack alignment is required to be maintained between every
2346 pair of insns, not just when the call is made. However, we assume here
2347 that such machines either do not have push insns (and hence preallocation
2348 would occur anyway) or the problem is taken care of with
2349 PUSH_ROUNDING. */
2351 if (! must_preallocate)
2353 int partial_seen = 0;
2354 poly_int64 copy_to_evaluate_size = 0;
2355 int i;
2357 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2359 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2360 partial_seen = 1;
2361 else if (partial_seen && args[i].reg == 0)
2362 must_preallocate = 1;
2363 /* We preallocate in case there are bounds passed
2364 in the bounds table to have precomputed address
2365 for bounds association. */
2366 else if (POINTER_BOUNDS_P (args[i].tree_value)
2367 && !args[i].reg)
2368 must_preallocate = 1;
2370 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2371 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2372 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2373 || TREE_CODE (args[i].tree_value) == COND_EXPR
2374 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2375 copy_to_evaluate_size
2376 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2379 if (maybe_ne (args_size->constant, 0)
2380 && maybe_ge (copy_to_evaluate_size * 2, args_size->constant))
2381 must_preallocate = 1;
2383 return must_preallocate;
2386 /* If we preallocated stack space, compute the address of each argument
2387 and store it into the ARGS array.
2389 We need not ensure it is a valid memory address here; it will be
2390 validized when it is used.
2392 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2394 static void
2395 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2397 if (argblock)
2399 rtx arg_reg = argblock;
2400 int i;
2401 poly_int64 arg_offset = 0;
2403 if (GET_CODE (argblock) == PLUS)
2405 arg_reg = XEXP (argblock, 0);
2406 arg_offset = rtx_to_poly_int64 (XEXP (argblock, 1));
2409 for (i = 0; i < num_actuals; i++)
2411 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2412 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2413 rtx addr;
2414 unsigned int align, boundary;
2415 poly_uint64 units_on_stack = 0;
2416 machine_mode partial_mode = VOIDmode;
2418 /* Skip this parm if it will not be passed on the stack. */
2419 if (! args[i].pass_on_stack
2420 && args[i].reg != 0
2421 && args[i].partial == 0)
2422 continue;
2424 if (TYPE_EMPTY_P (TREE_TYPE (args[i].tree_value)))
2425 continue;
2427 /* Pointer Bounds are never passed on the stack. */
2428 if (POINTER_BOUNDS_P (args[i].tree_value))
2429 continue;
2431 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, offset);
2432 addr = plus_constant (Pmode, addr, arg_offset);
2434 if (args[i].partial != 0)
2436 /* Only part of the parameter is being passed on the stack.
2437 Generate a simple memory reference of the correct size. */
2438 units_on_stack = args[i].locate.size.constant;
2439 poly_uint64 bits_on_stack = units_on_stack * BITS_PER_UNIT;
2440 partial_mode = int_mode_for_size (bits_on_stack, 1).else_blk ();
2441 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2442 set_mem_size (args[i].stack, units_on_stack);
2444 else
2446 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2447 set_mem_attributes (args[i].stack,
2448 TREE_TYPE (args[i].tree_value), 1);
2450 align = BITS_PER_UNIT;
2451 boundary = args[i].locate.boundary;
2452 poly_int64 offset_val;
2453 if (args[i].locate.where_pad != PAD_DOWNWARD)
2454 align = boundary;
2455 else if (poly_int_rtx_p (offset, &offset_val))
2457 align = least_bit_hwi (boundary);
2458 unsigned int offset_align
2459 = known_alignment (offset_val) * BITS_PER_UNIT;
2460 if (offset_align != 0)
2461 align = MIN (align, offset_align);
2463 set_mem_align (args[i].stack, align);
2465 addr = simplify_gen_binary (PLUS, Pmode, arg_reg, slot_offset);
2466 addr = plus_constant (Pmode, addr, arg_offset);
2468 if (args[i].partial != 0)
2470 /* Only part of the parameter is being passed on the stack.
2471 Generate a simple memory reference of the correct size.
2473 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2474 set_mem_size (args[i].stack_slot, units_on_stack);
2476 else
2478 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2479 set_mem_attributes (args[i].stack_slot,
2480 TREE_TYPE (args[i].tree_value), 1);
2482 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2484 /* Function incoming arguments may overlap with sibling call
2485 outgoing arguments and we cannot allow reordering of reads
2486 from function arguments with stores to outgoing arguments
2487 of sibling calls. */
2488 set_mem_alias_set (args[i].stack, 0);
2489 set_mem_alias_set (args[i].stack_slot, 0);
2494 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2495 in a call instruction.
2497 FNDECL is the tree node for the target function. For an indirect call
2498 FNDECL will be NULL_TREE.
2500 ADDR is the operand 0 of CALL_EXPR for this call. */
2502 static rtx
2503 rtx_for_function_call (tree fndecl, tree addr)
2505 rtx funexp;
2507 /* Get the function to call, in the form of RTL. */
2508 if (fndecl)
2510 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2511 TREE_USED (fndecl) = 1;
2513 /* Get a SYMBOL_REF rtx for the function address. */
2514 funexp = XEXP (DECL_RTL (fndecl), 0);
2516 else
2517 /* Generate an rtx (probably a pseudo-register) for the address. */
2519 push_temp_slots ();
2520 funexp = expand_normal (addr);
2521 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2523 return funexp;
2526 /* Return the static chain for this function, if any. */
2529 rtx_for_static_chain (const_tree fndecl_or_type, bool incoming_p)
2531 if (DECL_P (fndecl_or_type) && !DECL_STATIC_CHAIN (fndecl_or_type))
2532 return NULL;
2534 return targetm.calls.static_chain (fndecl_or_type, incoming_p);
2537 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2538 static struct
2540 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2541 or NULL_RTX if none has been scanned yet. */
2542 rtx_insn *scan_start;
2543 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2544 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2545 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2546 with fixed offset, or PC if this is with variable or unknown offset. */
2547 vec<rtx> cache;
2548 } internal_arg_pointer_exp_state;
2550 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2552 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2553 the tail call sequence, starting with first insn that hasn't been
2554 scanned yet, and note for each pseudo on the LHS whether it is based
2555 on crtl->args.internal_arg_pointer or not, and what offset from that
2556 that pointer it has. */
2558 static void
2559 internal_arg_pointer_based_exp_scan (void)
2561 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2563 if (scan_start == NULL_RTX)
2564 insn = get_insns ();
2565 else
2566 insn = NEXT_INSN (scan_start);
2568 while (insn)
2570 rtx set = single_set (insn);
2571 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2573 rtx val = NULL_RTX;
2574 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2575 /* Punt on pseudos set multiple times. */
2576 if (idx < internal_arg_pointer_exp_state.cache.length ()
2577 && (internal_arg_pointer_exp_state.cache[idx]
2578 != NULL_RTX))
2579 val = pc_rtx;
2580 else
2581 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2582 if (val != NULL_RTX)
2584 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2585 internal_arg_pointer_exp_state.cache
2586 .safe_grow_cleared (idx + 1);
2587 internal_arg_pointer_exp_state.cache[idx] = val;
2590 if (NEXT_INSN (insn) == NULL_RTX)
2591 scan_start = insn;
2592 insn = NEXT_INSN (insn);
2595 internal_arg_pointer_exp_state.scan_start = scan_start;
2598 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2599 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2600 it with fixed offset, or PC if this is with variable or unknown offset.
2601 TOPLEVEL is true if the function is invoked at the topmost level. */
2603 static rtx
2604 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2606 if (CONSTANT_P (rtl))
2607 return NULL_RTX;
2609 if (rtl == crtl->args.internal_arg_pointer)
2610 return const0_rtx;
2612 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2613 return NULL_RTX;
2615 poly_int64 offset;
2616 if (GET_CODE (rtl) == PLUS && poly_int_rtx_p (XEXP (rtl, 1), &offset))
2618 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2619 if (val == NULL_RTX || val == pc_rtx)
2620 return val;
2621 return plus_constant (Pmode, val, offset);
2624 /* When called at the topmost level, scan pseudo assignments in between the
2625 last scanned instruction in the tail call sequence and the latest insn
2626 in that sequence. */
2627 if (toplevel)
2628 internal_arg_pointer_based_exp_scan ();
2630 if (REG_P (rtl))
2632 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2633 if (idx < internal_arg_pointer_exp_state.cache.length ())
2634 return internal_arg_pointer_exp_state.cache[idx];
2636 return NULL_RTX;
2639 subrtx_iterator::array_type array;
2640 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2642 const_rtx x = *iter;
2643 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2644 return pc_rtx;
2645 if (MEM_P (x))
2646 iter.skip_subrtxes ();
2649 return NULL_RTX;
2652 /* Return true if SIZE bytes starting from address ADDR might overlap an
2653 already-clobbered argument area. This function is used to determine
2654 if we should give up a sibcall. */
2656 static bool
2657 mem_might_overlap_already_clobbered_arg_p (rtx addr, poly_uint64 size)
2659 poly_int64 i;
2660 unsigned HOST_WIDE_INT start, end;
2661 rtx val;
2663 if (bitmap_empty_p (stored_args_map)
2664 && stored_args_watermark == HOST_WIDE_INT_M1U)
2665 return false;
2666 val = internal_arg_pointer_based_exp (addr, true);
2667 if (val == NULL_RTX)
2668 return false;
2669 else if (!poly_int_rtx_p (val, &i))
2670 return true;
2672 if (known_eq (size, 0U))
2673 return false;
2675 if (STACK_GROWS_DOWNWARD)
2676 i -= crtl->args.pretend_args_size;
2677 else
2678 i += crtl->args.pretend_args_size;
2680 if (ARGS_GROW_DOWNWARD)
2681 i = -i - size;
2683 /* We can ignore any references to the function's pretend args,
2684 which at this point would manifest as negative values of I. */
2685 if (known_le (i, 0) && known_le (size, poly_uint64 (-i)))
2686 return false;
2688 start = maybe_lt (i, 0) ? 0 : constant_lower_bound (i);
2689 if (!(i + size).is_constant (&end))
2690 end = HOST_WIDE_INT_M1U;
2692 if (end > stored_args_watermark)
2693 return true;
2695 end = MIN (end, SBITMAP_SIZE (stored_args_map));
2696 for (unsigned HOST_WIDE_INT k = start; k < end; ++k)
2697 if (bitmap_bit_p (stored_args_map, k))
2698 return true;
2700 return false;
2703 /* Do the register loads required for any wholly-register parms or any
2704 parms which are passed both on the stack and in a register. Their
2705 expressions were already evaluated.
2707 Mark all register-parms as living through the call, putting these USE
2708 insns in the CALL_INSN_FUNCTION_USAGE field.
2710 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2711 checking, setting *SIBCALL_FAILURE if appropriate. */
2713 static void
2714 load_register_parameters (struct arg_data *args, int num_actuals,
2715 rtx *call_fusage, int flags, int is_sibcall,
2716 int *sibcall_failure)
2718 int i, j;
2720 for (i = 0; i < num_actuals; i++)
2722 rtx reg = ((flags & ECF_SIBCALL)
2723 ? args[i].tail_call_reg : args[i].reg);
2724 if (reg)
2726 int partial = args[i].partial;
2727 int nregs;
2728 poly_int64 size = 0;
2729 HOST_WIDE_INT const_size = 0;
2730 rtx_insn *before_arg = get_last_insn ();
2731 /* Set non-negative if we must move a word at a time, even if
2732 just one word (e.g, partial == 4 && mode == DFmode). Set
2733 to -1 if we just use a normal move insn. This value can be
2734 zero if the argument is a zero size structure. */
2735 nregs = -1;
2736 if (GET_CODE (reg) == PARALLEL)
2738 else if (partial)
2740 gcc_assert (partial % UNITS_PER_WORD == 0);
2741 nregs = partial / UNITS_PER_WORD;
2743 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2745 /* Variable-sized parameters should be described by a
2746 PARALLEL instead. */
2747 const_size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2748 gcc_assert (const_size >= 0);
2749 nregs = (const_size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2750 size = const_size;
2752 else
2753 size = GET_MODE_SIZE (args[i].mode);
2755 /* Handle calls that pass values in multiple non-contiguous
2756 locations. The Irix 6 ABI has examples of this. */
2758 if (GET_CODE (reg) == PARALLEL)
2759 emit_group_move (reg, args[i].parallel_value);
2761 /* If simple case, just do move. If normal partial, store_one_arg
2762 has already loaded the register for us. In all other cases,
2763 load the register(s) from memory. */
2765 else if (nregs == -1)
2767 emit_move_insn (reg, args[i].value);
2768 #ifdef BLOCK_REG_PADDING
2769 /* Handle case where we have a value that needs shifting
2770 up to the msb. eg. a QImode value and we're padding
2771 upward on a BYTES_BIG_ENDIAN machine. */
2772 if (args[i].locate.where_pad
2773 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD))
2775 gcc_checking_assert (ordered_p (size, UNITS_PER_WORD));
2776 if (maybe_lt (size, UNITS_PER_WORD))
2778 rtx x;
2779 poly_int64 shift
2780 = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2782 /* Assigning REG here rather than a temp makes
2783 CALL_FUSAGE report the whole reg as used.
2784 Strictly speaking, the call only uses SIZE
2785 bytes at the msb end, but it doesn't seem worth
2786 generating rtl to say that. */
2787 reg = gen_rtx_REG (word_mode, REGNO (reg));
2788 x = expand_shift (LSHIFT_EXPR, word_mode,
2789 reg, shift, reg, 1);
2790 if (x != reg)
2791 emit_move_insn (reg, x);
2794 #endif
2797 /* If we have pre-computed the values to put in the registers in
2798 the case of non-aligned structures, copy them in now. */
2800 else if (args[i].n_aligned_regs != 0)
2801 for (j = 0; j < args[i].n_aligned_regs; j++)
2802 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2803 args[i].aligned_regs[j]);
2805 else if (partial == 0 || args[i].pass_on_stack)
2807 /* SIZE and CONST_SIZE are 0 for partial arguments and
2808 the size of a BLKmode type otherwise. */
2809 gcc_checking_assert (known_eq (size, const_size));
2810 rtx mem = validize_mem (copy_rtx (args[i].value));
2812 /* Check for overlap with already clobbered argument area,
2813 providing that this has non-zero size. */
2814 if (is_sibcall
2815 && const_size != 0
2816 && (mem_might_overlap_already_clobbered_arg_p
2817 (XEXP (args[i].value, 0), const_size)))
2818 *sibcall_failure = 1;
2820 if (const_size % UNITS_PER_WORD == 0
2821 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2822 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2823 else
2825 if (nregs > 1)
2826 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2827 args[i].mode);
2828 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2829 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2830 unsigned int bitsize = const_size * BITS_PER_UNIT - bitoff;
2831 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2832 word_mode, word_mode, false,
2833 NULL);
2834 if (BYTES_BIG_ENDIAN)
2835 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2836 BITS_PER_WORD - bitsize, dest, 1);
2837 if (x != dest)
2838 emit_move_insn (dest, x);
2841 /* Handle a BLKmode that needs shifting. */
2842 if (nregs == 1 && const_size < UNITS_PER_WORD
2843 #ifdef BLOCK_REG_PADDING
2844 && args[i].locate.where_pad == PAD_DOWNWARD
2845 #else
2846 && BYTES_BIG_ENDIAN
2847 #endif
2850 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2851 int shift = (UNITS_PER_WORD - const_size) * BITS_PER_UNIT;
2852 enum tree_code dir = (BYTES_BIG_ENDIAN
2853 ? RSHIFT_EXPR : LSHIFT_EXPR);
2854 rtx x;
2856 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2857 if (x != dest)
2858 emit_move_insn (dest, x);
2862 /* When a parameter is a block, and perhaps in other cases, it is
2863 possible that it did a load from an argument slot that was
2864 already clobbered. */
2865 if (is_sibcall
2866 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2867 *sibcall_failure = 1;
2869 /* Handle calls that pass values in multiple non-contiguous
2870 locations. The Irix 6 ABI has examples of this. */
2871 if (GET_CODE (reg) == PARALLEL)
2872 use_group_regs (call_fusage, reg);
2873 else if (nregs == -1)
2874 use_reg_mode (call_fusage, reg,
2875 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2876 else if (nregs > 0)
2877 use_regs (call_fusage, REGNO (reg), nregs);
2882 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2883 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2884 bytes, then we would need to push some additional bytes to pad the
2885 arguments. So, we try to compute an adjust to the stack pointer for an
2886 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2887 bytes. Then, when the arguments are pushed the stack will be perfectly
2888 aligned.
2890 Return true if this optimization is possible, storing the adjustment
2891 in ADJUSTMENT_OUT and setting ARGS_SIZE->CONSTANT to the number of
2892 bytes that should be popped after the call. */
2894 static bool
2895 combine_pending_stack_adjustment_and_call (poly_int64_pod *adjustment_out,
2896 poly_int64 unadjusted_args_size,
2897 struct args_size *args_size,
2898 unsigned int preferred_unit_stack_boundary)
2900 /* The number of bytes to pop so that the stack will be
2901 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2902 poly_int64 adjustment;
2903 /* The alignment of the stack after the arguments are pushed, if we
2904 just pushed the arguments without adjust the stack here. */
2905 unsigned HOST_WIDE_INT unadjusted_alignment;
2907 if (!known_misalignment (stack_pointer_delta + unadjusted_args_size,
2908 preferred_unit_stack_boundary,
2909 &unadjusted_alignment))
2910 return false;
2912 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2913 as possible -- leaving just enough left to cancel out the
2914 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2915 PENDING_STACK_ADJUST is non-negative, and congruent to
2916 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2918 /* Begin by trying to pop all the bytes. */
2919 unsigned HOST_WIDE_INT tmp_misalignment;
2920 if (!known_misalignment (pending_stack_adjust,
2921 preferred_unit_stack_boundary,
2922 &tmp_misalignment))
2923 return false;
2924 unadjusted_alignment -= tmp_misalignment;
2925 adjustment = pending_stack_adjust;
2926 /* Push enough additional bytes that the stack will be aligned
2927 after the arguments are pushed. */
2928 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2929 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2931 /* We need to know whether the adjusted argument size
2932 (UNADJUSTED_ARGS_SIZE - ADJUSTMENT) constitutes an allocation
2933 or a deallocation. */
2934 if (!ordered_p (adjustment, unadjusted_args_size))
2935 return false;
2937 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2938 bytes after the call. The right number is the entire
2939 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2940 by the arguments in the first place. */
2941 args_size->constant
2942 = pending_stack_adjust - adjustment + unadjusted_args_size;
2944 *adjustment_out = adjustment;
2945 return true;
2948 /* Scan X expression if it does not dereference any argument slots
2949 we already clobbered by tail call arguments (as noted in stored_args_map
2950 bitmap).
2951 Return nonzero if X expression dereferences such argument slots,
2952 zero otherwise. */
2954 static int
2955 check_sibcall_argument_overlap_1 (rtx x)
2957 RTX_CODE code;
2958 int i, j;
2959 const char *fmt;
2961 if (x == NULL_RTX)
2962 return 0;
2964 code = GET_CODE (x);
2966 /* We need not check the operands of the CALL expression itself. */
2967 if (code == CALL)
2968 return 0;
2970 if (code == MEM)
2971 return (mem_might_overlap_already_clobbered_arg_p
2972 (XEXP (x, 0), GET_MODE_SIZE (GET_MODE (x))));
2974 /* Scan all subexpressions. */
2975 fmt = GET_RTX_FORMAT (code);
2976 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2978 if (*fmt == 'e')
2980 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2981 return 1;
2983 else if (*fmt == 'E')
2985 for (j = 0; j < XVECLEN (x, i); j++)
2986 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2987 return 1;
2990 return 0;
2993 /* Scan sequence after INSN if it does not dereference any argument slots
2994 we already clobbered by tail call arguments (as noted in stored_args_map
2995 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2996 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2997 should be 0). Return nonzero if sequence after INSN dereferences such argument
2998 slots, zero otherwise. */
3000 static int
3001 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
3002 int mark_stored_args_map)
3004 poly_uint64 low, high;
3005 unsigned HOST_WIDE_INT const_low, const_high;
3007 if (insn == NULL_RTX)
3008 insn = get_insns ();
3009 else
3010 insn = NEXT_INSN (insn);
3012 for (; insn; insn = NEXT_INSN (insn))
3013 if (INSN_P (insn)
3014 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
3015 break;
3017 if (mark_stored_args_map)
3019 if (ARGS_GROW_DOWNWARD)
3020 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
3021 else
3022 low = arg->locate.slot_offset.constant;
3023 high = low + arg->locate.size.constant;
3025 const_low = constant_lower_bound (low);
3026 if (high.is_constant (&const_high))
3027 for (unsigned HOST_WIDE_INT i = const_low; i < const_high; ++i)
3028 bitmap_set_bit (stored_args_map, i);
3029 else
3030 stored_args_watermark = MIN (stored_args_watermark, const_low);
3032 return insn != NULL_RTX;
3035 /* Given that a function returns a value of mode MODE at the most
3036 significant end of hard register VALUE, shift VALUE left or right
3037 as specified by LEFT_P. Return true if some action was needed. */
3039 bool
3040 shift_return_value (machine_mode mode, bool left_p, rtx value)
3042 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
3043 machine_mode value_mode = GET_MODE (value);
3044 poly_int64 shift = GET_MODE_BITSIZE (value_mode) - GET_MODE_BITSIZE (mode);
3046 if (known_eq (shift, 0))
3047 return false;
3049 /* Use ashr rather than lshr for right shifts. This is for the benefit
3050 of the MIPS port, which requires SImode values to be sign-extended
3051 when stored in 64-bit registers. */
3052 if (!force_expand_binop (value_mode, left_p ? ashl_optab : ashr_optab,
3053 value, gen_int_shift_amount (value_mode, shift),
3054 value, 1, OPTAB_WIDEN))
3055 gcc_unreachable ();
3056 return true;
3059 /* If X is a likely-spilled register value, copy it to a pseudo
3060 register and return that register. Return X otherwise. */
3062 static rtx
3063 avoid_likely_spilled_reg (rtx x)
3065 rtx new_rtx;
3067 if (REG_P (x)
3068 && HARD_REGISTER_P (x)
3069 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
3071 /* Make sure that we generate a REG rather than a CONCAT.
3072 Moves into CONCATs can need nontrivial instructions,
3073 and the whole point of this function is to avoid
3074 using the hard register directly in such a situation. */
3075 generating_concat_p = 0;
3076 new_rtx = gen_reg_rtx (GET_MODE (x));
3077 generating_concat_p = 1;
3078 emit_move_insn (new_rtx, x);
3079 return new_rtx;
3081 return x;
3084 /* Helper function for expand_call.
3085 Return false is EXP is not implementable as a sibling call. */
3087 static bool
3088 can_implement_as_sibling_call_p (tree exp,
3089 rtx structure_value_addr,
3090 tree funtype,
3091 int reg_parm_stack_space ATTRIBUTE_UNUSED,
3092 tree fndecl,
3093 int flags,
3094 tree addr,
3095 const args_size &args_size)
3097 if (!targetm.have_sibcall_epilogue ())
3099 maybe_complain_about_tail_call
3100 (exp,
3101 "machine description does not have"
3102 " a sibcall_epilogue instruction pattern");
3103 return false;
3106 /* Doing sibling call optimization needs some work, since
3107 structure_value_addr can be allocated on the stack.
3108 It does not seem worth the effort since few optimizable
3109 sibling calls will return a structure. */
3110 if (structure_value_addr != NULL_RTX)
3112 maybe_complain_about_tail_call (exp, "callee returns a structure");
3113 return false;
3116 #ifdef REG_PARM_STACK_SPACE
3117 /* If outgoing reg parm stack space changes, we can not do sibcall. */
3118 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
3119 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
3120 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
3122 maybe_complain_about_tail_call (exp,
3123 "inconsistent size of stack space"
3124 " allocated for arguments which are"
3125 " passed in registers");
3126 return false;
3128 #endif
3130 /* Check whether the target is able to optimize the call
3131 into a sibcall. */
3132 if (!targetm.function_ok_for_sibcall (fndecl, exp))
3134 maybe_complain_about_tail_call (exp,
3135 "target is not able to optimize the"
3136 " call into a sibling call");
3137 return false;
3140 /* Functions that do not return exactly once may not be sibcall
3141 optimized. */
3142 if (flags & ECF_RETURNS_TWICE)
3144 maybe_complain_about_tail_call (exp, "callee returns twice");
3145 return false;
3147 if (flags & ECF_NORETURN)
3149 maybe_complain_about_tail_call (exp, "callee does not return");
3150 return false;
3153 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
3155 maybe_complain_about_tail_call (exp, "volatile function type");
3156 return false;
3159 /* If the called function is nested in the current one, it might access
3160 some of the caller's arguments, but could clobber them beforehand if
3161 the argument areas are shared. */
3162 if (fndecl && decl_function_context (fndecl) == current_function_decl)
3164 maybe_complain_about_tail_call (exp, "nested function");
3165 return false;
3168 /* If this function requires more stack slots than the current
3169 function, we cannot change it into a sibling call.
3170 crtl->args.pretend_args_size is not part of the
3171 stack allocated by our caller. */
3172 if (maybe_gt (args_size.constant,
3173 crtl->args.size - crtl->args.pretend_args_size))
3175 maybe_complain_about_tail_call (exp,
3176 "callee required more stack slots"
3177 " than the caller");
3178 return false;
3181 /* If the callee pops its own arguments, then it must pop exactly
3182 the same number of arguments as the current function. */
3183 if (maybe_ne (targetm.calls.return_pops_args (fndecl, funtype,
3184 args_size.constant),
3185 targetm.calls.return_pops_args (current_function_decl,
3186 TREE_TYPE
3187 (current_function_decl),
3188 crtl->args.size)))
3190 maybe_complain_about_tail_call (exp,
3191 "inconsistent number of"
3192 " popped arguments");
3193 return false;
3196 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
3198 maybe_complain_about_tail_call (exp, "frontend does not support"
3199 " sibling call");
3200 return false;
3203 /* All checks passed. */
3204 return true;
3207 /* Generate all the code for a CALL_EXPR exp
3208 and return an rtx for its value.
3209 Store the value in TARGET (specified as an rtx) if convenient.
3210 If the value is stored in TARGET then TARGET is returned.
3211 If IGNORE is nonzero, then we ignore the value of the function call. */
3214 expand_call (tree exp, rtx target, int ignore)
3216 /* Nonzero if we are currently expanding a call. */
3217 static int currently_expanding_call = 0;
3219 /* RTX for the function to be called. */
3220 rtx funexp;
3221 /* Sequence of insns to perform a normal "call". */
3222 rtx_insn *normal_call_insns = NULL;
3223 /* Sequence of insns to perform a tail "call". */
3224 rtx_insn *tail_call_insns = NULL;
3225 /* Data type of the function. */
3226 tree funtype;
3227 tree type_arg_types;
3228 tree rettype;
3229 /* Declaration of the function being called,
3230 or 0 if the function is computed (not known by name). */
3231 tree fndecl = 0;
3232 /* The type of the function being called. */
3233 tree fntype;
3234 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
3235 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
3236 int pass;
3238 /* Register in which non-BLKmode value will be returned,
3239 or 0 if no value or if value is BLKmode. */
3240 rtx valreg;
3241 /* Register(s) in which bounds are returned. */
3242 rtx valbnd = NULL;
3243 /* Address where we should return a BLKmode value;
3244 0 if value not BLKmode. */
3245 rtx structure_value_addr = 0;
3246 /* Nonzero if that address is being passed by treating it as
3247 an extra, implicit first parameter. Otherwise,
3248 it is passed by being copied directly into struct_value_rtx. */
3249 int structure_value_addr_parm = 0;
3250 /* Holds the value of implicit argument for the struct value. */
3251 tree structure_value_addr_value = NULL_TREE;
3252 /* Size of aggregate value wanted, or zero if none wanted
3253 or if we are using the non-reentrant PCC calling convention
3254 or expecting the value in registers. */
3255 poly_int64 struct_value_size = 0;
3256 /* Nonzero if called function returns an aggregate in memory PCC style,
3257 by returning the address of where to find it. */
3258 int pcc_struct_value = 0;
3259 rtx struct_value = 0;
3261 /* Number of actual parameters in this call, including struct value addr. */
3262 int num_actuals;
3263 /* Number of named args. Args after this are anonymous ones
3264 and they must all go on the stack. */
3265 int n_named_args;
3266 /* Number of complex actual arguments that need to be split. */
3267 int num_complex_actuals = 0;
3269 /* Vector of information about each argument.
3270 Arguments are numbered in the order they will be pushed,
3271 not the order they are written. */
3272 struct arg_data *args;
3274 /* Total size in bytes of all the stack-parms scanned so far. */
3275 struct args_size args_size;
3276 struct args_size adjusted_args_size;
3277 /* Size of arguments before any adjustments (such as rounding). */
3278 poly_int64 unadjusted_args_size;
3279 /* Data on reg parms scanned so far. */
3280 CUMULATIVE_ARGS args_so_far_v;
3281 cumulative_args_t args_so_far;
3282 /* Nonzero if a reg parm has been scanned. */
3283 int reg_parm_seen;
3284 /* Nonzero if this is an indirect function call. */
3286 /* Nonzero if we must avoid push-insns in the args for this call.
3287 If stack space is allocated for register parameters, but not by the
3288 caller, then it is preallocated in the fixed part of the stack frame.
3289 So the entire argument block must then be preallocated (i.e., we
3290 ignore PUSH_ROUNDING in that case). */
3292 int must_preallocate = !PUSH_ARGS;
3294 /* Size of the stack reserved for parameter registers. */
3295 int reg_parm_stack_space = 0;
3297 /* Address of space preallocated for stack parms
3298 (on machines that lack push insns), or 0 if space not preallocated. */
3299 rtx argblock = 0;
3301 /* Mask of ECF_ and ERF_ flags. */
3302 int flags = 0;
3303 int return_flags = 0;
3304 #ifdef REG_PARM_STACK_SPACE
3305 /* Define the boundary of the register parm stack space that needs to be
3306 saved, if any. */
3307 int low_to_save, high_to_save;
3308 rtx save_area = 0; /* Place that it is saved */
3309 #endif
3311 unsigned int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3312 char *initial_stack_usage_map = stack_usage_map;
3313 unsigned HOST_WIDE_INT initial_stack_usage_watermark = stack_usage_watermark;
3314 char *stack_usage_map_buf = NULL;
3316 poly_int64 old_stack_allocated;
3318 /* State variables to track stack modifications. */
3319 rtx old_stack_level = 0;
3320 int old_stack_arg_under_construction = 0;
3321 poly_int64 old_pending_adj = 0;
3322 int old_inhibit_defer_pop = inhibit_defer_pop;
3324 /* Some stack pointer alterations we make are performed via
3325 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3326 which we then also need to save/restore along the way. */
3327 poly_int64 old_stack_pointer_delta = 0;
3329 rtx call_fusage;
3330 tree addr = CALL_EXPR_FN (exp);
3331 int i;
3332 /* The alignment of the stack, in bits. */
3333 unsigned HOST_WIDE_INT preferred_stack_boundary;
3334 /* The alignment of the stack, in bytes. */
3335 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3336 /* The static chain value to use for this call. */
3337 rtx static_chain_value;
3338 /* See if this is "nothrow" function call. */
3339 if (TREE_NOTHROW (exp))
3340 flags |= ECF_NOTHROW;
3342 /* See if we can find a DECL-node for the actual function, and get the
3343 function attributes (flags) from the function decl or type node. */
3344 fndecl = get_callee_fndecl (exp);
3345 if (fndecl)
3347 fntype = TREE_TYPE (fndecl);
3348 flags |= flags_from_decl_or_type (fndecl);
3349 return_flags |= decl_return_flags (fndecl);
3351 else
3353 fntype = TREE_TYPE (TREE_TYPE (addr));
3354 flags |= flags_from_decl_or_type (fntype);
3355 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3356 flags |= ECF_BY_DESCRIPTOR;
3358 rettype = TREE_TYPE (exp);
3360 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3362 /* Warn if this value is an aggregate type,
3363 regardless of which calling convention we are using for it. */
3364 if (AGGREGATE_TYPE_P (rettype))
3365 warning (OPT_Waggregate_return, "function call has aggregate value");
3367 /* If the result of a non looping pure or const function call is
3368 ignored (or void), and none of its arguments are volatile, we can
3369 avoid expanding the call and just evaluate the arguments for
3370 side-effects. */
3371 if ((flags & (ECF_CONST | ECF_PURE))
3372 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3373 && (ignore || target == const0_rtx
3374 || TYPE_MODE (rettype) == VOIDmode))
3376 bool volatilep = false;
3377 tree arg;
3378 call_expr_arg_iterator iter;
3380 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3381 if (TREE_THIS_VOLATILE (arg))
3383 volatilep = true;
3384 break;
3387 if (! volatilep)
3389 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3390 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3391 return const0_rtx;
3395 #ifdef REG_PARM_STACK_SPACE
3396 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3397 #endif
3399 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3400 && reg_parm_stack_space > 0 && PUSH_ARGS)
3401 must_preallocate = 1;
3403 /* Set up a place to return a structure. */
3405 /* Cater to broken compilers. */
3406 if (aggregate_value_p (exp, fntype))
3408 /* This call returns a big structure. */
3409 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3411 #ifdef PCC_STATIC_STRUCT_RETURN
3413 pcc_struct_value = 1;
3415 #else /* not PCC_STATIC_STRUCT_RETURN */
3417 if (!poly_int_tree_p (TYPE_SIZE_UNIT (rettype), &struct_value_size))
3418 struct_value_size = -1;
3420 /* Even if it is semantically safe to use the target as the return
3421 slot, it may be not sufficiently aligned for the return type. */
3422 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3423 && target
3424 && MEM_P (target)
3425 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3426 && targetm.slow_unaligned_access (TYPE_MODE (rettype),
3427 MEM_ALIGN (target))))
3428 structure_value_addr = XEXP (target, 0);
3429 else
3431 /* For variable-sized objects, we must be called with a target
3432 specified. If we were to allocate space on the stack here,
3433 we would have no way of knowing when to free it. */
3434 rtx d = assign_temp (rettype, 1, 1);
3435 structure_value_addr = XEXP (d, 0);
3436 target = 0;
3439 #endif /* not PCC_STATIC_STRUCT_RETURN */
3442 /* Figure out the amount to which the stack should be aligned. */
3443 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3444 if (fndecl)
3446 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3447 /* Without automatic stack alignment, we can't increase preferred
3448 stack boundary. With automatic stack alignment, it is
3449 unnecessary since unless we can guarantee that all callers will
3450 align the outgoing stack properly, callee has to align its
3451 stack anyway. */
3452 if (i
3453 && i->preferred_incoming_stack_boundary
3454 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3455 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3458 /* Operand 0 is a pointer-to-function; get the type of the function. */
3459 funtype = TREE_TYPE (addr);
3460 gcc_assert (POINTER_TYPE_P (funtype));
3461 funtype = TREE_TYPE (funtype);
3463 /* Count whether there are actual complex arguments that need to be split
3464 into their real and imaginary parts. Munge the type_arg_types
3465 appropriately here as well. */
3466 if (targetm.calls.split_complex_arg)
3468 call_expr_arg_iterator iter;
3469 tree arg;
3470 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3472 tree type = TREE_TYPE (arg);
3473 if (type && TREE_CODE (type) == COMPLEX_TYPE
3474 && targetm.calls.split_complex_arg (type))
3475 num_complex_actuals++;
3477 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3479 else
3480 type_arg_types = TYPE_ARG_TYPES (funtype);
3482 if (flags & ECF_MAY_BE_ALLOCA)
3483 cfun->calls_alloca = 1;
3485 /* If struct_value_rtx is 0, it means pass the address
3486 as if it were an extra parameter. Put the argument expression
3487 in structure_value_addr_value. */
3488 if (structure_value_addr && struct_value == 0)
3490 /* If structure_value_addr is a REG other than
3491 virtual_outgoing_args_rtx, we can use always use it. If it
3492 is not a REG, we must always copy it into a register.
3493 If it is virtual_outgoing_args_rtx, we must copy it to another
3494 register in some cases. */
3495 rtx temp = (!REG_P (structure_value_addr)
3496 || (ACCUMULATE_OUTGOING_ARGS
3497 && stack_arg_under_construction
3498 && structure_value_addr == virtual_outgoing_args_rtx)
3499 ? copy_addr_to_reg (convert_memory_address
3500 (Pmode, structure_value_addr))
3501 : structure_value_addr);
3503 structure_value_addr_value =
3504 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3505 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3508 /* Count the arguments and set NUM_ACTUALS. */
3509 num_actuals =
3510 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3512 /* Compute number of named args.
3513 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3515 if (type_arg_types != 0)
3516 n_named_args
3517 = (list_length (type_arg_types)
3518 /* Count the struct value address, if it is passed as a parm. */
3519 + structure_value_addr_parm);
3520 else
3521 /* If we know nothing, treat all args as named. */
3522 n_named_args = num_actuals;
3524 /* Start updating where the next arg would go.
3526 On some machines (such as the PA) indirect calls have a different
3527 calling convention than normal calls. The fourth argument in
3528 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3529 or not. */
3530 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3531 args_so_far = pack_cumulative_args (&args_so_far_v);
3533 /* Now possibly adjust the number of named args.
3534 Normally, don't include the last named arg if anonymous args follow.
3535 We do include the last named arg if
3536 targetm.calls.strict_argument_naming() returns nonzero.
3537 (If no anonymous args follow, the result of list_length is actually
3538 one too large. This is harmless.)
3540 If targetm.calls.pretend_outgoing_varargs_named() returns
3541 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3542 this machine will be able to place unnamed args that were passed
3543 in registers into the stack. So treat all args as named. This
3544 allows the insns emitting for a specific argument list to be
3545 independent of the function declaration.
3547 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3548 we do not have any reliable way to pass unnamed args in
3549 registers, so we must force them into memory. */
3551 if (type_arg_types != 0
3552 && targetm.calls.strict_argument_naming (args_so_far))
3554 else if (type_arg_types != 0
3555 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3556 /* Don't include the last named arg. */
3557 --n_named_args;
3558 else
3559 /* Treat all args as named. */
3560 n_named_args = num_actuals;
3562 /* Make a vector to hold all the information about each arg. */
3563 args = XCNEWVEC (struct arg_data, num_actuals);
3565 /* Build up entries in the ARGS array, compute the size of the
3566 arguments into ARGS_SIZE, etc. */
3567 initialize_argument_information (num_actuals, args, &args_size,
3568 n_named_args, exp,
3569 structure_value_addr_value, fndecl, fntype,
3570 args_so_far, reg_parm_stack_space,
3571 &old_stack_level, &old_pending_adj,
3572 &must_preallocate, &flags,
3573 &try_tail_call, CALL_FROM_THUNK_P (exp));
3575 if (args_size.var)
3576 must_preallocate = 1;
3578 /* Now make final decision about preallocating stack space. */
3579 must_preallocate = finalize_must_preallocate (must_preallocate,
3580 num_actuals, args,
3581 &args_size);
3583 /* If the structure value address will reference the stack pointer, we
3584 must stabilize it. We don't need to do this if we know that we are
3585 not going to adjust the stack pointer in processing this call. */
3587 if (structure_value_addr
3588 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3589 || reg_mentioned_p (virtual_outgoing_args_rtx,
3590 structure_value_addr))
3591 && (args_size.var
3592 || (!ACCUMULATE_OUTGOING_ARGS
3593 && maybe_ne (args_size.constant, 0))))
3594 structure_value_addr = copy_to_reg (structure_value_addr);
3596 /* Tail calls can make things harder to debug, and we've traditionally
3597 pushed these optimizations into -O2. Don't try if we're already
3598 expanding a call, as that means we're an argument. Don't try if
3599 there's cleanups, as we know there's code to follow the call. */
3601 if (currently_expanding_call++ != 0
3602 || !flag_optimize_sibling_calls
3603 || args_size.var
3604 || dbg_cnt (tail_call) == false)
3605 try_tail_call = 0;
3607 /* If the user has marked the function as requiring tail-call
3608 optimization, attempt it. */
3609 if (must_tail_call)
3610 try_tail_call = 1;
3612 /* Rest of purposes for tail call optimizations to fail. */
3613 if (try_tail_call)
3614 try_tail_call = can_implement_as_sibling_call_p (exp,
3615 structure_value_addr,
3616 funtype,
3617 reg_parm_stack_space,
3618 fndecl,
3619 flags, addr, args_size);
3621 /* Check if caller and callee disagree in promotion of function
3622 return value. */
3623 if (try_tail_call)
3625 machine_mode caller_mode, caller_promoted_mode;
3626 machine_mode callee_mode, callee_promoted_mode;
3627 int caller_unsignedp, callee_unsignedp;
3628 tree caller_res = DECL_RESULT (current_function_decl);
3630 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3631 caller_mode = DECL_MODE (caller_res);
3632 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3633 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3634 caller_promoted_mode
3635 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3636 &caller_unsignedp,
3637 TREE_TYPE (current_function_decl), 1);
3638 callee_promoted_mode
3639 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3640 &callee_unsignedp,
3641 funtype, 1);
3642 if (caller_mode != VOIDmode
3643 && (caller_promoted_mode != callee_promoted_mode
3644 || ((caller_mode != caller_promoted_mode
3645 || callee_mode != callee_promoted_mode)
3646 && (caller_unsignedp != callee_unsignedp
3647 || partial_subreg_p (caller_mode, callee_mode)))))
3649 try_tail_call = 0;
3650 maybe_complain_about_tail_call (exp,
3651 "caller and callee disagree in"
3652 " promotion of function"
3653 " return value");
3657 /* Ensure current function's preferred stack boundary is at least
3658 what we need. Stack alignment may also increase preferred stack
3659 boundary. */
3660 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3661 crtl->preferred_stack_boundary = preferred_stack_boundary;
3662 else
3663 preferred_stack_boundary = crtl->preferred_stack_boundary;
3665 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3667 /* We want to make two insn chains; one for a sibling call, the other
3668 for a normal call. We will select one of the two chains after
3669 initial RTL generation is complete. */
3670 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3672 int sibcall_failure = 0;
3673 /* We want to emit any pending stack adjustments before the tail
3674 recursion "call". That way we know any adjustment after the tail
3675 recursion call can be ignored if we indeed use the tail
3676 call expansion. */
3677 saved_pending_stack_adjust save;
3678 rtx_insn *insns, *before_call, *after_args;
3679 rtx next_arg_reg;
3681 if (pass == 0)
3683 /* State variables we need to save and restore between
3684 iterations. */
3685 save_pending_stack_adjust (&save);
3687 if (pass)
3688 flags &= ~ECF_SIBCALL;
3689 else
3690 flags |= ECF_SIBCALL;
3692 /* Other state variables that we must reinitialize each time
3693 through the loop (that are not initialized by the loop itself). */
3694 argblock = 0;
3695 call_fusage = 0;
3697 /* Start a new sequence for the normal call case.
3699 From this point on, if the sibling call fails, we want to set
3700 sibcall_failure instead of continuing the loop. */
3701 start_sequence ();
3703 /* Don't let pending stack adjusts add up to too much.
3704 Also, do all pending adjustments now if there is any chance
3705 this might be a call to alloca or if we are expanding a sibling
3706 call sequence.
3707 Also do the adjustments before a throwing call, otherwise
3708 exception handling can fail; PR 19225. */
3709 if (maybe_ge (pending_stack_adjust, 32)
3710 || (maybe_ne (pending_stack_adjust, 0)
3711 && (flags & ECF_MAY_BE_ALLOCA))
3712 || (maybe_ne (pending_stack_adjust, 0)
3713 && flag_exceptions && !(flags & ECF_NOTHROW))
3714 || pass == 0)
3715 do_pending_stack_adjust ();
3717 /* Precompute any arguments as needed. */
3718 if (pass)
3719 precompute_arguments (num_actuals, args);
3721 /* Now we are about to start emitting insns that can be deleted
3722 if a libcall is deleted. */
3723 if (pass && (flags & ECF_MALLOC))
3724 start_sequence ();
3726 if (pass == 0
3727 && crtl->stack_protect_guard
3728 && targetm.stack_protect_runtime_enabled_p ())
3729 stack_protect_epilogue ();
3731 adjusted_args_size = args_size;
3732 /* Compute the actual size of the argument block required. The variable
3733 and constant sizes must be combined, the size may have to be rounded,
3734 and there may be a minimum required size. When generating a sibcall
3735 pattern, do not round up, since we'll be re-using whatever space our
3736 caller provided. */
3737 unadjusted_args_size
3738 = compute_argument_block_size (reg_parm_stack_space,
3739 &adjusted_args_size,
3740 fndecl, fntype,
3741 (pass == 0 ? 0
3742 : preferred_stack_boundary));
3744 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3746 /* The argument block when performing a sibling call is the
3747 incoming argument block. */
3748 if (pass == 0)
3750 argblock = crtl->args.internal_arg_pointer;
3751 if (STACK_GROWS_DOWNWARD)
3752 argblock
3753 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3754 else
3755 argblock
3756 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3758 HOST_WIDE_INT map_size = constant_lower_bound (args_size.constant);
3759 stored_args_map = sbitmap_alloc (map_size);
3760 bitmap_clear (stored_args_map);
3761 stored_args_watermark = HOST_WIDE_INT_M1U;
3764 /* If we have no actual push instructions, or shouldn't use them,
3765 make space for all args right now. */
3766 else if (adjusted_args_size.var != 0)
3768 if (old_stack_level == 0)
3770 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3771 old_stack_pointer_delta = stack_pointer_delta;
3772 old_pending_adj = pending_stack_adjust;
3773 pending_stack_adjust = 0;
3774 /* stack_arg_under_construction says whether a stack arg is
3775 being constructed at the old stack level. Pushing the stack
3776 gets a clean outgoing argument block. */
3777 old_stack_arg_under_construction = stack_arg_under_construction;
3778 stack_arg_under_construction = 0;
3780 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3781 if (flag_stack_usage_info)
3782 current_function_has_unbounded_dynamic_stack_size = 1;
3784 else
3786 /* Note that we must go through the motions of allocating an argument
3787 block even if the size is zero because we may be storing args
3788 in the area reserved for register arguments, which may be part of
3789 the stack frame. */
3791 poly_int64 needed = adjusted_args_size.constant;
3793 /* Store the maximum argument space used. It will be pushed by
3794 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3795 checking). */
3797 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
3798 needed);
3800 if (must_preallocate)
3802 if (ACCUMULATE_OUTGOING_ARGS)
3804 /* Since the stack pointer will never be pushed, it is
3805 possible for the evaluation of a parm to clobber
3806 something we have already written to the stack.
3807 Since most function calls on RISC machines do not use
3808 the stack, this is uncommon, but must work correctly.
3810 Therefore, we save any area of the stack that was already
3811 written and that we are using. Here we set up to do this
3812 by making a new stack usage map from the old one. The
3813 actual save will be done by store_one_arg.
3815 Another approach might be to try to reorder the argument
3816 evaluations to avoid this conflicting stack usage. */
3818 /* Since we will be writing into the entire argument area,
3819 the map must be allocated for its entire size, not just
3820 the part that is the responsibility of the caller. */
3821 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3822 needed += reg_parm_stack_space;
3824 poly_int64 limit = needed;
3825 if (ARGS_GROW_DOWNWARD)
3826 limit += 1;
3828 /* For polynomial sizes, this is the maximum possible
3829 size needed for arguments with a constant size
3830 and offset. */
3831 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
3832 highest_outgoing_arg_in_use
3833 = MAX (initial_highest_arg_in_use, const_limit);
3835 free (stack_usage_map_buf);
3836 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3837 stack_usage_map = stack_usage_map_buf;
3839 if (initial_highest_arg_in_use)
3840 memcpy (stack_usage_map, initial_stack_usage_map,
3841 initial_highest_arg_in_use);
3843 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3844 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3845 (highest_outgoing_arg_in_use
3846 - initial_highest_arg_in_use));
3847 needed = 0;
3849 /* The address of the outgoing argument list must not be
3850 copied to a register here, because argblock would be left
3851 pointing to the wrong place after the call to
3852 allocate_dynamic_stack_space below. */
3854 argblock = virtual_outgoing_args_rtx;
3856 else
3858 /* Try to reuse some or all of the pending_stack_adjust
3859 to get this space. */
3860 if (inhibit_defer_pop == 0
3861 && (combine_pending_stack_adjustment_and_call
3862 (&needed,
3863 unadjusted_args_size,
3864 &adjusted_args_size,
3865 preferred_unit_stack_boundary)))
3867 /* combine_pending_stack_adjustment_and_call computes
3868 an adjustment before the arguments are allocated.
3869 Account for them and see whether or not the stack
3870 needs to go up or down. */
3871 needed = unadjusted_args_size - needed;
3873 /* Checked by
3874 combine_pending_stack_adjustment_and_call. */
3875 gcc_checking_assert (ordered_p (needed, 0));
3876 if (maybe_lt (needed, 0))
3878 /* We're releasing stack space. */
3879 /* ??? We can avoid any adjustment at all if we're
3880 already aligned. FIXME. */
3881 pending_stack_adjust = -needed;
3882 do_pending_stack_adjust ();
3883 needed = 0;
3885 else
3886 /* We need to allocate space. We'll do that in
3887 push_block below. */
3888 pending_stack_adjust = 0;
3891 /* Special case this because overhead of `push_block' in
3892 this case is non-trivial. */
3893 if (known_eq (needed, 0))
3894 argblock = virtual_outgoing_args_rtx;
3895 else
3897 rtx needed_rtx = gen_int_mode (needed, Pmode);
3898 argblock = push_block (needed_rtx, 0, 0);
3899 if (ARGS_GROW_DOWNWARD)
3900 argblock = plus_constant (Pmode, argblock, needed);
3903 /* We only really need to call `copy_to_reg' in the case
3904 where push insns are going to be used to pass ARGBLOCK
3905 to a function call in ARGS. In that case, the stack
3906 pointer changes value from the allocation point to the
3907 call point, and hence the value of
3908 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3909 as well always do it. */
3910 argblock = copy_to_reg (argblock);
3915 if (ACCUMULATE_OUTGOING_ARGS)
3917 /* The save/restore code in store_one_arg handles all
3918 cases except one: a constructor call (including a C
3919 function returning a BLKmode struct) to initialize
3920 an argument. */
3921 if (stack_arg_under_construction)
3923 rtx push_size
3924 = (gen_int_mode
3925 (adjusted_args_size.constant
3926 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl ? fntype
3927 : TREE_TYPE (fndecl))
3928 ? 0 : reg_parm_stack_space), Pmode));
3929 if (old_stack_level == 0)
3931 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3932 old_stack_pointer_delta = stack_pointer_delta;
3933 old_pending_adj = pending_stack_adjust;
3934 pending_stack_adjust = 0;
3935 /* stack_arg_under_construction says whether a stack
3936 arg is being constructed at the old stack level.
3937 Pushing the stack gets a clean outgoing argument
3938 block. */
3939 old_stack_arg_under_construction
3940 = stack_arg_under_construction;
3941 stack_arg_under_construction = 0;
3942 /* Make a new map for the new argument list. */
3943 free (stack_usage_map_buf);
3944 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3945 stack_usage_map = stack_usage_map_buf;
3946 highest_outgoing_arg_in_use = 0;
3947 stack_usage_watermark = HOST_WIDE_INT_M1U;
3949 /* We can pass TRUE as the 4th argument because we just
3950 saved the stack pointer and will restore it right after
3951 the call. */
3952 allocate_dynamic_stack_space (push_size, 0, BIGGEST_ALIGNMENT,
3953 -1, true);
3956 /* If argument evaluation might modify the stack pointer,
3957 copy the address of the argument list to a register. */
3958 for (i = 0; i < num_actuals; i++)
3959 if (args[i].pass_on_stack)
3961 argblock = copy_addr_to_reg (argblock);
3962 break;
3966 compute_argument_addresses (args, argblock, num_actuals);
3968 /* Stack is properly aligned, pops can't safely be deferred during
3969 the evaluation of the arguments. */
3970 NO_DEFER_POP;
3972 /* Precompute all register parameters. It isn't safe to compute
3973 anything once we have started filling any specific hard regs.
3974 TLS symbols sometimes need a call to resolve. Precompute
3975 register parameters before any stack pointer manipulation
3976 to avoid unaligned stack in the called function. */
3977 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3979 OK_DEFER_POP;
3981 /* Perform stack alignment before the first push (the last arg). */
3982 if (argblock == 0
3983 && maybe_gt (adjusted_args_size.constant, reg_parm_stack_space)
3984 && maybe_ne (adjusted_args_size.constant, unadjusted_args_size))
3986 /* When the stack adjustment is pending, we get better code
3987 by combining the adjustments. */
3988 if (maybe_ne (pending_stack_adjust, 0)
3989 && ! inhibit_defer_pop
3990 && (combine_pending_stack_adjustment_and_call
3991 (&pending_stack_adjust,
3992 unadjusted_args_size,
3993 &adjusted_args_size,
3994 preferred_unit_stack_boundary)))
3995 do_pending_stack_adjust ();
3996 else if (argblock == 0)
3997 anti_adjust_stack (gen_int_mode (adjusted_args_size.constant
3998 - unadjusted_args_size,
3999 Pmode));
4001 /* Now that the stack is properly aligned, pops can't safely
4002 be deferred during the evaluation of the arguments. */
4003 NO_DEFER_POP;
4005 /* Record the maximum pushed stack space size. We need to delay
4006 doing it this far to take into account the optimization done
4007 by combine_pending_stack_adjustment_and_call. */
4008 if (flag_stack_usage_info
4009 && !ACCUMULATE_OUTGOING_ARGS
4010 && pass
4011 && adjusted_args_size.var == 0)
4013 poly_int64 pushed = (adjusted_args_size.constant
4014 + pending_stack_adjust);
4015 current_function_pushed_stack_size
4016 = upper_bound (current_function_pushed_stack_size, pushed);
4019 funexp = rtx_for_function_call (fndecl, addr);
4021 if (CALL_EXPR_STATIC_CHAIN (exp))
4022 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
4023 else
4024 static_chain_value = 0;
4026 #ifdef REG_PARM_STACK_SPACE
4027 /* Save the fixed argument area if it's part of the caller's frame and
4028 is clobbered by argument setup for this call. */
4029 if (ACCUMULATE_OUTGOING_ARGS && pass)
4030 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4031 &low_to_save, &high_to_save);
4032 #endif
4034 /* Now store (and compute if necessary) all non-register parms.
4035 These come before register parms, since they can require block-moves,
4036 which could clobber the registers used for register parms.
4037 Parms which have partial registers are not stored here,
4038 but we do preallocate space here if they want that. */
4040 for (i = 0; i < num_actuals; i++)
4042 /* Delay bounds until all other args are stored. */
4043 if (POINTER_BOUNDS_P (args[i].tree_value))
4044 continue;
4045 else if (args[i].reg == 0 || args[i].pass_on_stack)
4047 rtx_insn *before_arg = get_last_insn ();
4049 /* We don't allow passing huge (> 2^30 B) arguments
4050 by value. It would cause an overflow later on. */
4051 if (constant_lower_bound (adjusted_args_size.constant)
4052 >= (1 << (HOST_BITS_PER_INT - 2)))
4054 sorry ("passing too large argument on stack");
4055 continue;
4058 if (store_one_arg (&args[i], argblock, flags,
4059 adjusted_args_size.var != 0,
4060 reg_parm_stack_space)
4061 || (pass == 0
4062 && check_sibcall_argument_overlap (before_arg,
4063 &args[i], 1)))
4064 sibcall_failure = 1;
4067 if (args[i].stack)
4068 call_fusage
4069 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
4070 gen_rtx_USE (VOIDmode, args[i].stack),
4071 call_fusage);
4074 /* If we have a parm that is passed in registers but not in memory
4075 and whose alignment does not permit a direct copy into registers,
4076 make a group of pseudos that correspond to each register that we
4077 will later fill. */
4078 if (STRICT_ALIGNMENT)
4079 store_unaligned_arguments_into_pseudos (args, num_actuals);
4081 /* Now store any partially-in-registers parm.
4082 This is the last place a block-move can happen. */
4083 if (reg_parm_seen)
4084 for (i = 0; i < num_actuals; i++)
4085 if (args[i].partial != 0 && ! args[i].pass_on_stack)
4087 rtx_insn *before_arg = get_last_insn ();
4089 /* On targets with weird calling conventions (e.g. PA) it's
4090 hard to ensure that all cases of argument overlap between
4091 stack and registers work. Play it safe and bail out. */
4092 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
4094 sibcall_failure = 1;
4095 break;
4098 if (store_one_arg (&args[i], argblock, flags,
4099 adjusted_args_size.var != 0,
4100 reg_parm_stack_space)
4101 || (pass == 0
4102 && check_sibcall_argument_overlap (before_arg,
4103 &args[i], 1)))
4104 sibcall_failure = 1;
4107 bool any_regs = false;
4108 for (i = 0; i < num_actuals; i++)
4109 if (args[i].reg != NULL_RTX)
4111 any_regs = true;
4112 targetm.calls.call_args (args[i].reg, funtype);
4114 if (!any_regs)
4115 targetm.calls.call_args (pc_rtx, funtype);
4117 /* Figure out the register where the value, if any, will come back. */
4118 valreg = 0;
4119 valbnd = 0;
4120 if (TYPE_MODE (rettype) != VOIDmode
4121 && ! structure_value_addr)
4123 if (pcc_struct_value)
4125 valreg = hard_function_value (build_pointer_type (rettype),
4126 fndecl, NULL, (pass == 0));
4127 if (CALL_WITH_BOUNDS_P (exp))
4128 valbnd = targetm.calls.
4129 chkp_function_value_bounds (build_pointer_type (rettype),
4130 fndecl, (pass == 0));
4132 else
4134 valreg = hard_function_value (rettype, fndecl, fntype,
4135 (pass == 0));
4136 if (CALL_WITH_BOUNDS_P (exp))
4137 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
4138 fndecl,
4139 (pass == 0));
4142 /* If VALREG is a PARALLEL whose first member has a zero
4143 offset, use that. This is for targets such as m68k that
4144 return the same value in multiple places. */
4145 if (GET_CODE (valreg) == PARALLEL)
4147 rtx elem = XVECEXP (valreg, 0, 0);
4148 rtx where = XEXP (elem, 0);
4149 rtx offset = XEXP (elem, 1);
4150 if (offset == const0_rtx
4151 && GET_MODE (where) == GET_MODE (valreg))
4152 valreg = where;
4156 /* Store all bounds not passed in registers. */
4157 for (i = 0; i < num_actuals; i++)
4159 if (POINTER_BOUNDS_P (args[i].tree_value)
4160 && !args[i].reg)
4161 store_bounds (&args[i],
4162 args[i].pointer_arg == -1
4163 ? NULL
4164 : &args[args[i].pointer_arg]);
4167 /* If register arguments require space on the stack and stack space
4168 was not preallocated, allocate stack space here for arguments
4169 passed in registers. */
4170 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
4171 && !ACCUMULATE_OUTGOING_ARGS
4172 && must_preallocate == 0 && reg_parm_stack_space > 0)
4173 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
4175 /* Pass the function the address in which to return a
4176 structure value. */
4177 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
4179 structure_value_addr
4180 = convert_memory_address (Pmode, structure_value_addr);
4181 emit_move_insn (struct_value,
4182 force_reg (Pmode,
4183 force_operand (structure_value_addr,
4184 NULL_RTX)));
4186 if (REG_P (struct_value))
4187 use_reg (&call_fusage, struct_value);
4190 after_args = get_last_insn ();
4191 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
4192 static_chain_value, &call_fusage,
4193 reg_parm_seen, flags);
4195 load_register_parameters (args, num_actuals, &call_fusage, flags,
4196 pass == 0, &sibcall_failure);
4198 /* Save a pointer to the last insn before the call, so that we can
4199 later safely search backwards to find the CALL_INSN. */
4200 before_call = get_last_insn ();
4202 /* Set up next argument register. For sibling calls on machines
4203 with register windows this should be the incoming register. */
4204 if (pass == 0)
4205 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
4206 VOIDmode,
4207 void_type_node,
4208 true);
4209 else
4210 next_arg_reg = targetm.calls.function_arg (args_so_far,
4211 VOIDmode, void_type_node,
4212 true);
4214 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
4216 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
4217 arg_nr = num_actuals - arg_nr - 1;
4218 if (arg_nr >= 0
4219 && arg_nr < num_actuals
4220 && args[arg_nr].reg
4221 && valreg
4222 && REG_P (valreg)
4223 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
4224 call_fusage
4225 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
4226 gen_rtx_SET (valreg, args[arg_nr].reg),
4227 call_fusage);
4229 /* All arguments and registers used for the call must be set up by
4230 now! */
4232 /* Stack must be properly aligned now. */
4233 gcc_assert (!pass
4234 || multiple_p (stack_pointer_delta,
4235 preferred_unit_stack_boundary));
4237 /* Generate the actual call instruction. */
4238 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
4239 adjusted_args_size.constant, struct_value_size,
4240 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
4241 flags, args_so_far);
4243 if (flag_ipa_ra)
4245 rtx_call_insn *last;
4246 rtx datum = NULL_RTX;
4247 if (fndecl != NULL_TREE)
4249 datum = XEXP (DECL_RTL (fndecl), 0);
4250 gcc_assert (datum != NULL_RTX
4251 && GET_CODE (datum) == SYMBOL_REF);
4253 last = last_call_insn ();
4254 add_reg_note (last, REG_CALL_DECL, datum);
4257 /* If the call setup or the call itself overlaps with anything
4258 of the argument setup we probably clobbered our call address.
4259 In that case we can't do sibcalls. */
4260 if (pass == 0
4261 && check_sibcall_argument_overlap (after_args, 0, 0))
4262 sibcall_failure = 1;
4264 /* If a non-BLKmode value is returned at the most significant end
4265 of a register, shift the register right by the appropriate amount
4266 and update VALREG accordingly. BLKmode values are handled by the
4267 group load/store machinery below. */
4268 if (!structure_value_addr
4269 && !pcc_struct_value
4270 && TYPE_MODE (rettype) != VOIDmode
4271 && TYPE_MODE (rettype) != BLKmode
4272 && REG_P (valreg)
4273 && targetm.calls.return_in_msb (rettype))
4275 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
4276 sibcall_failure = 1;
4277 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
4280 if (pass && (flags & ECF_MALLOC))
4282 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4283 rtx_insn *last, *insns;
4285 /* The return value from a malloc-like function is a pointer. */
4286 if (TREE_CODE (rettype) == POINTER_TYPE)
4287 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
4289 emit_move_insn (temp, valreg);
4291 /* The return value from a malloc-like function can not alias
4292 anything else. */
4293 last = get_last_insn ();
4294 add_reg_note (last, REG_NOALIAS, temp);
4296 /* Write out the sequence. */
4297 insns = get_insns ();
4298 end_sequence ();
4299 emit_insn (insns);
4300 valreg = temp;
4303 /* For calls to `setjmp', etc., inform
4304 function.c:setjmp_warnings that it should complain if
4305 nonvolatile values are live. For functions that cannot
4306 return, inform flow that control does not fall through. */
4308 if ((flags & ECF_NORETURN) || pass == 0)
4310 /* The barrier must be emitted
4311 immediately after the CALL_INSN. Some ports emit more
4312 than just a CALL_INSN above, so we must search for it here. */
4314 rtx_insn *last = get_last_insn ();
4315 while (!CALL_P (last))
4317 last = PREV_INSN (last);
4318 /* There was no CALL_INSN? */
4319 gcc_assert (last != before_call);
4322 emit_barrier_after (last);
4324 /* Stack adjustments after a noreturn call are dead code.
4325 However when NO_DEFER_POP is in effect, we must preserve
4326 stack_pointer_delta. */
4327 if (inhibit_defer_pop == 0)
4329 stack_pointer_delta = old_stack_allocated;
4330 pending_stack_adjust = 0;
4334 /* If value type not void, return an rtx for the value. */
4336 if (TYPE_MODE (rettype) == VOIDmode
4337 || ignore)
4338 target = const0_rtx;
4339 else if (structure_value_addr)
4341 if (target == 0 || !MEM_P (target))
4343 target
4344 = gen_rtx_MEM (TYPE_MODE (rettype),
4345 memory_address (TYPE_MODE (rettype),
4346 structure_value_addr));
4347 set_mem_attributes (target, rettype, 1);
4350 else if (pcc_struct_value)
4352 /* This is the special C++ case where we need to
4353 know what the true target was. We take care to
4354 never use this value more than once in one expression. */
4355 target = gen_rtx_MEM (TYPE_MODE (rettype),
4356 copy_to_reg (valreg));
4357 set_mem_attributes (target, rettype, 1);
4359 /* Handle calls that return values in multiple non-contiguous locations.
4360 The Irix 6 ABI has examples of this. */
4361 else if (GET_CODE (valreg) == PARALLEL)
4363 if (target == 0)
4364 target = emit_group_move_into_temps (valreg);
4365 else if (rtx_equal_p (target, valreg))
4367 else if (GET_CODE (target) == PARALLEL)
4368 /* Handle the result of a emit_group_move_into_temps
4369 call in the previous pass. */
4370 emit_group_move (target, valreg);
4371 else
4372 emit_group_store (target, valreg, rettype,
4373 int_size_in_bytes (rettype));
4375 else if (target
4376 && GET_MODE (target) == TYPE_MODE (rettype)
4377 && GET_MODE (target) == GET_MODE (valreg))
4379 bool may_overlap = false;
4381 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4382 reg to a plain register. */
4383 if (!REG_P (target) || HARD_REGISTER_P (target))
4384 valreg = avoid_likely_spilled_reg (valreg);
4386 /* If TARGET is a MEM in the argument area, and we have
4387 saved part of the argument area, then we can't store
4388 directly into TARGET as it may get overwritten when we
4389 restore the argument save area below. Don't work too
4390 hard though and simply force TARGET to a register if it
4391 is a MEM; the optimizer is quite likely to sort it out. */
4392 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4393 for (i = 0; i < num_actuals; i++)
4394 if (args[i].save_area)
4396 may_overlap = true;
4397 break;
4400 if (may_overlap)
4401 target = copy_to_reg (valreg);
4402 else
4404 /* TARGET and VALREG cannot be equal at this point
4405 because the latter would not have
4406 REG_FUNCTION_VALUE_P true, while the former would if
4407 it were referring to the same register.
4409 If they refer to the same register, this move will be
4410 a no-op, except when function inlining is being
4411 done. */
4412 emit_move_insn (target, valreg);
4414 /* If we are setting a MEM, this code must be executed.
4415 Since it is emitted after the call insn, sibcall
4416 optimization cannot be performed in that case. */
4417 if (MEM_P (target))
4418 sibcall_failure = 1;
4421 else
4422 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4424 /* If we promoted this return value, make the proper SUBREG.
4425 TARGET might be const0_rtx here, so be careful. */
4426 if (REG_P (target)
4427 && TYPE_MODE (rettype) != BLKmode
4428 && GET_MODE (target) != TYPE_MODE (rettype))
4430 tree type = rettype;
4431 int unsignedp = TYPE_UNSIGNED (type);
4432 machine_mode pmode;
4434 /* Ensure we promote as expected, and get the new unsignedness. */
4435 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4436 funtype, 1);
4437 gcc_assert (GET_MODE (target) == pmode);
4439 poly_uint64 offset = subreg_lowpart_offset (TYPE_MODE (type),
4440 GET_MODE (target));
4441 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4442 SUBREG_PROMOTED_VAR_P (target) = 1;
4443 SUBREG_PROMOTED_SET (target, unsignedp);
4446 /* If size of args is variable or this was a constructor call for a stack
4447 argument, restore saved stack-pointer value. */
4449 if (old_stack_level)
4451 rtx_insn *prev = get_last_insn ();
4453 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4454 stack_pointer_delta = old_stack_pointer_delta;
4456 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4458 pending_stack_adjust = old_pending_adj;
4459 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4460 stack_arg_under_construction = old_stack_arg_under_construction;
4461 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4462 stack_usage_map = initial_stack_usage_map;
4463 stack_usage_watermark = initial_stack_usage_watermark;
4464 sibcall_failure = 1;
4466 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4468 #ifdef REG_PARM_STACK_SPACE
4469 if (save_area)
4470 restore_fixed_argument_area (save_area, argblock,
4471 high_to_save, low_to_save);
4472 #endif
4474 /* If we saved any argument areas, restore them. */
4475 for (i = 0; i < num_actuals; i++)
4476 if (args[i].save_area)
4478 machine_mode save_mode = GET_MODE (args[i].save_area);
4479 rtx stack_area
4480 = gen_rtx_MEM (save_mode,
4481 memory_address (save_mode,
4482 XEXP (args[i].stack_slot, 0)));
4484 if (save_mode != BLKmode)
4485 emit_move_insn (stack_area, args[i].save_area);
4486 else
4487 emit_block_move (stack_area, args[i].save_area,
4488 (gen_int_mode
4489 (args[i].locate.size.constant, Pmode)),
4490 BLOCK_OP_CALL_PARM);
4493 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4494 stack_usage_map = initial_stack_usage_map;
4495 stack_usage_watermark = initial_stack_usage_watermark;
4498 /* If this was alloca, record the new stack level. */
4499 if (flags & ECF_MAY_BE_ALLOCA)
4500 record_new_stack_level ();
4502 /* Free up storage we no longer need. */
4503 for (i = 0; i < num_actuals; ++i)
4504 free (args[i].aligned_regs);
4506 targetm.calls.end_call_args ();
4508 insns = get_insns ();
4509 end_sequence ();
4511 if (pass == 0)
4513 tail_call_insns = insns;
4515 /* Restore the pending stack adjustment now that we have
4516 finished generating the sibling call sequence. */
4518 restore_pending_stack_adjust (&save);
4520 /* Prepare arg structure for next iteration. */
4521 for (i = 0; i < num_actuals; i++)
4523 args[i].value = 0;
4524 args[i].aligned_regs = 0;
4525 args[i].stack = 0;
4528 sbitmap_free (stored_args_map);
4529 internal_arg_pointer_exp_state.scan_start = NULL;
4530 internal_arg_pointer_exp_state.cache.release ();
4532 else
4534 normal_call_insns = insns;
4536 /* Verify that we've deallocated all the stack we used. */
4537 gcc_assert ((flags & ECF_NORETURN)
4538 || known_eq (old_stack_allocated,
4539 stack_pointer_delta
4540 - pending_stack_adjust));
4543 /* If something prevents making this a sibling call,
4544 zero out the sequence. */
4545 if (sibcall_failure)
4546 tail_call_insns = NULL;
4547 else
4548 break;
4551 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4552 arguments too, as argument area is now clobbered by the call. */
4553 if (tail_call_insns)
4555 emit_insn (tail_call_insns);
4556 crtl->tail_call_emit = true;
4558 else
4560 emit_insn (normal_call_insns);
4561 if (try_tail_call)
4562 /* Ideally we'd emit a message for all of the ways that it could
4563 have failed. */
4564 maybe_complain_about_tail_call (exp, "tail call production failed");
4567 currently_expanding_call--;
4569 free (stack_usage_map_buf);
4570 free (args);
4572 /* Join result with returned bounds so caller may use them if needed. */
4573 target = chkp_join_splitted_slot (target, valbnd);
4575 return target;
4578 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4579 this function's incoming arguments.
4581 At the start of RTL generation we know the only REG_EQUIV notes
4582 in the rtl chain are those for incoming arguments, so we can look
4583 for REG_EQUIV notes between the start of the function and the
4584 NOTE_INSN_FUNCTION_BEG.
4586 This is (slight) overkill. We could keep track of the highest
4587 argument we clobber and be more selective in removing notes, but it
4588 does not seem to be worth the effort. */
4590 void
4591 fixup_tail_calls (void)
4593 rtx_insn *insn;
4595 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4597 rtx note;
4599 /* There are never REG_EQUIV notes for the incoming arguments
4600 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4601 if (NOTE_P (insn)
4602 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4603 break;
4605 note = find_reg_note (insn, REG_EQUIV, 0);
4606 if (note)
4607 remove_note (insn, note);
4608 note = find_reg_note (insn, REG_EQUIV, 0);
4609 gcc_assert (!note);
4613 /* Traverse a list of TYPES and expand all complex types into their
4614 components. */
4615 static tree
4616 split_complex_types (tree types)
4618 tree p;
4620 /* Before allocating memory, check for the common case of no complex. */
4621 for (p = types; p; p = TREE_CHAIN (p))
4623 tree type = TREE_VALUE (p);
4624 if (TREE_CODE (type) == COMPLEX_TYPE
4625 && targetm.calls.split_complex_arg (type))
4626 goto found;
4628 return types;
4630 found:
4631 types = copy_list (types);
4633 for (p = types; p; p = TREE_CHAIN (p))
4635 tree complex_type = TREE_VALUE (p);
4637 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4638 && targetm.calls.split_complex_arg (complex_type))
4640 tree next, imag;
4642 /* Rewrite complex type with component type. */
4643 TREE_VALUE (p) = TREE_TYPE (complex_type);
4644 next = TREE_CHAIN (p);
4646 /* Add another component type for the imaginary part. */
4647 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4648 TREE_CHAIN (p) = imag;
4649 TREE_CHAIN (imag) = next;
4651 /* Skip the newly created node. */
4652 p = TREE_CHAIN (p);
4656 return types;
4659 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4660 for a value of mode OUTMODE,
4661 with NARGS different arguments, passed as ARGS.
4662 Store the return value if RETVAL is nonzero: store it in VALUE if
4663 VALUE is nonnull, otherwise pick a convenient location. In either
4664 case return the location of the stored value.
4666 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4667 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4668 other types of library calls. */
4671 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4672 enum libcall_type fn_type,
4673 machine_mode outmode, int nargs, rtx_mode_t *args)
4675 /* Total size in bytes of all the stack-parms scanned so far. */
4676 struct args_size args_size;
4677 /* Size of arguments before any adjustments (such as rounding). */
4678 struct args_size original_args_size;
4679 int argnum;
4680 rtx fun;
4681 /* Todo, choose the correct decl type of orgfun. Sadly this information
4682 isn't present here, so we default to native calling abi here. */
4683 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4684 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4685 int count;
4686 rtx argblock = 0;
4687 CUMULATIVE_ARGS args_so_far_v;
4688 cumulative_args_t args_so_far;
4689 struct arg
4691 rtx value;
4692 machine_mode mode;
4693 rtx reg;
4694 int partial;
4695 struct locate_and_pad_arg_data locate;
4696 rtx save_area;
4698 struct arg *argvec;
4699 int old_inhibit_defer_pop = inhibit_defer_pop;
4700 rtx call_fusage = 0;
4701 rtx mem_value = 0;
4702 rtx valreg;
4703 int pcc_struct_value = 0;
4704 poly_int64 struct_value_size = 0;
4705 int flags;
4706 int reg_parm_stack_space = 0;
4707 poly_int64 needed;
4708 rtx_insn *before_call;
4709 bool have_push_fusage;
4710 tree tfom; /* type_for_mode (outmode, 0) */
4712 #ifdef REG_PARM_STACK_SPACE
4713 /* Define the boundary of the register parm stack space that needs to be
4714 save, if any. */
4715 int low_to_save = 0, high_to_save = 0;
4716 rtx save_area = 0; /* Place that it is saved. */
4717 #endif
4719 /* Size of the stack reserved for parameter registers. */
4720 unsigned int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4721 char *initial_stack_usage_map = stack_usage_map;
4722 unsigned HOST_WIDE_INT initial_stack_usage_watermark = stack_usage_watermark;
4723 char *stack_usage_map_buf = NULL;
4725 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4727 #ifdef REG_PARM_STACK_SPACE
4728 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4729 #endif
4731 /* By default, library functions cannot throw. */
4732 flags = ECF_NOTHROW;
4734 switch (fn_type)
4736 case LCT_NORMAL:
4737 break;
4738 case LCT_CONST:
4739 flags |= ECF_CONST;
4740 break;
4741 case LCT_PURE:
4742 flags |= ECF_PURE;
4743 break;
4744 case LCT_NORETURN:
4745 flags |= ECF_NORETURN;
4746 break;
4747 case LCT_THROW:
4748 flags &= ~ECF_NOTHROW;
4749 break;
4750 case LCT_RETURNS_TWICE:
4751 flags = ECF_RETURNS_TWICE;
4752 break;
4754 fun = orgfun;
4756 /* Ensure current function's preferred stack boundary is at least
4757 what we need. */
4758 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4759 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4761 /* If this kind of value comes back in memory,
4762 decide where in memory it should come back. */
4763 if (outmode != VOIDmode)
4765 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4766 if (aggregate_value_p (tfom, 0))
4768 #ifdef PCC_STATIC_STRUCT_RETURN
4769 rtx pointer_reg
4770 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4771 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4772 pcc_struct_value = 1;
4773 if (value == 0)
4774 value = gen_reg_rtx (outmode);
4775 #else /* not PCC_STATIC_STRUCT_RETURN */
4776 struct_value_size = GET_MODE_SIZE (outmode);
4777 if (value != 0 && MEM_P (value))
4778 mem_value = value;
4779 else
4780 mem_value = assign_temp (tfom, 1, 1);
4781 #endif
4782 /* This call returns a big structure. */
4783 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4786 else
4787 tfom = void_type_node;
4789 /* ??? Unfinished: must pass the memory address as an argument. */
4791 /* Copy all the libcall-arguments out of the varargs data
4792 and into a vector ARGVEC.
4794 Compute how to pass each argument. We only support a very small subset
4795 of the full argument passing conventions to limit complexity here since
4796 library functions shouldn't have many args. */
4798 argvec = XALLOCAVEC (struct arg, nargs + 1);
4799 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4801 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4802 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4803 #else
4804 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4805 #endif
4806 args_so_far = pack_cumulative_args (&args_so_far_v);
4808 args_size.constant = 0;
4809 args_size.var = 0;
4811 count = 0;
4813 push_temp_slots ();
4815 /* If there's a structure value address to be passed,
4816 either pass it in the special place, or pass it as an extra argument. */
4817 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4819 rtx addr = XEXP (mem_value, 0);
4821 nargs++;
4823 /* Make sure it is a reasonable operand for a move or push insn. */
4824 if (!REG_P (addr) && !MEM_P (addr)
4825 && !(CONSTANT_P (addr)
4826 && targetm.legitimate_constant_p (Pmode, addr)))
4827 addr = force_operand (addr, NULL_RTX);
4829 argvec[count].value = addr;
4830 argvec[count].mode = Pmode;
4831 argvec[count].partial = 0;
4833 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4834 Pmode, NULL_TREE, true);
4835 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4836 NULL_TREE, 1) == 0);
4838 locate_and_pad_parm (Pmode, NULL_TREE,
4839 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4841 #else
4842 argvec[count].reg != 0,
4843 #endif
4844 reg_parm_stack_space, 0,
4845 NULL_TREE, &args_size, &argvec[count].locate);
4847 if (argvec[count].reg == 0 || argvec[count].partial != 0
4848 || reg_parm_stack_space > 0)
4849 args_size.constant += argvec[count].locate.size.constant;
4851 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4853 count++;
4856 for (unsigned int i = 0; count < nargs; i++, count++)
4858 rtx val = args[i].first;
4859 machine_mode mode = args[i].second;
4860 int unsigned_p = 0;
4862 /* We cannot convert the arg value to the mode the library wants here;
4863 must do it earlier where we know the signedness of the arg. */
4864 gcc_assert (mode != BLKmode
4865 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4867 /* Make sure it is a reasonable operand for a move or push insn. */
4868 if (!REG_P (val) && !MEM_P (val)
4869 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4870 val = force_operand (val, NULL_RTX);
4872 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4874 rtx slot;
4875 int must_copy
4876 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4878 /* If this was a CONST function, it is now PURE since it now
4879 reads memory. */
4880 if (flags & ECF_CONST)
4882 flags &= ~ECF_CONST;
4883 flags |= ECF_PURE;
4886 if (MEM_P (val) && !must_copy)
4888 tree val_expr = MEM_EXPR (val);
4889 if (val_expr)
4890 mark_addressable (val_expr);
4891 slot = val;
4893 else
4895 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4896 1, 1);
4897 emit_move_insn (slot, val);
4900 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4901 gen_rtx_USE (VOIDmode, slot),
4902 call_fusage);
4903 if (must_copy)
4904 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4905 gen_rtx_CLOBBER (VOIDmode,
4906 slot),
4907 call_fusage);
4909 mode = Pmode;
4910 val = force_operand (XEXP (slot, 0), NULL_RTX);
4913 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4914 argvec[count].mode = mode;
4915 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4916 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4917 NULL_TREE, true);
4919 argvec[count].partial
4920 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4922 if (argvec[count].reg == 0
4923 || argvec[count].partial != 0
4924 || reg_parm_stack_space > 0)
4926 locate_and_pad_parm (mode, NULL_TREE,
4927 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4929 #else
4930 argvec[count].reg != 0,
4931 #endif
4932 reg_parm_stack_space, argvec[count].partial,
4933 NULL_TREE, &args_size, &argvec[count].locate);
4934 args_size.constant += argvec[count].locate.size.constant;
4935 gcc_assert (!argvec[count].locate.size.var);
4937 #ifdef BLOCK_REG_PADDING
4938 else
4939 /* The argument is passed entirely in registers. See at which
4940 end it should be padded. */
4941 argvec[count].locate.where_pad =
4942 BLOCK_REG_PADDING (mode, NULL_TREE,
4943 known_le (GET_MODE_SIZE (mode), UNITS_PER_WORD));
4944 #endif
4946 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4949 /* If this machine requires an external definition for library
4950 functions, write one out. */
4951 assemble_external_libcall (fun);
4953 original_args_size = args_size;
4954 args_size.constant = (aligned_upper_bound (args_size.constant
4955 + stack_pointer_delta,
4956 STACK_BYTES)
4957 - stack_pointer_delta);
4959 args_size.constant = upper_bound (args_size.constant,
4960 reg_parm_stack_space);
4962 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4963 args_size.constant -= reg_parm_stack_space;
4965 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
4966 args_size.constant);
4968 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4970 poly_int64 pushed = args_size.constant + pending_stack_adjust;
4971 current_function_pushed_stack_size
4972 = upper_bound (current_function_pushed_stack_size, pushed);
4975 if (ACCUMULATE_OUTGOING_ARGS)
4977 /* Since the stack pointer will never be pushed, it is possible for
4978 the evaluation of a parm to clobber something we have already
4979 written to the stack. Since most function calls on RISC machines
4980 do not use the stack, this is uncommon, but must work correctly.
4982 Therefore, we save any area of the stack that was already written
4983 and that we are using. Here we set up to do this by making a new
4984 stack usage map from the old one.
4986 Another approach might be to try to reorder the argument
4987 evaluations to avoid this conflicting stack usage. */
4989 needed = args_size.constant;
4991 /* Since we will be writing into the entire argument area, the
4992 map must be allocated for its entire size, not just the part that
4993 is the responsibility of the caller. */
4994 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4995 needed += reg_parm_stack_space;
4997 poly_int64 limit = needed;
4998 if (ARGS_GROW_DOWNWARD)
4999 limit += 1;
5001 /* For polynomial sizes, this is the maximum possible size needed
5002 for arguments with a constant size and offset. */
5003 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
5004 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
5005 const_limit);
5007 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
5008 stack_usage_map = stack_usage_map_buf;
5010 if (initial_highest_arg_in_use)
5011 memcpy (stack_usage_map, initial_stack_usage_map,
5012 initial_highest_arg_in_use);
5014 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
5015 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
5016 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
5017 needed = 0;
5019 /* We must be careful to use virtual regs before they're instantiated,
5020 and real regs afterwards. Loop optimization, for example, can create
5021 new libcalls after we've instantiated the virtual regs, and if we
5022 use virtuals anyway, they won't match the rtl patterns. */
5024 if (virtuals_instantiated)
5025 argblock = plus_constant (Pmode, stack_pointer_rtx,
5026 STACK_POINTER_OFFSET);
5027 else
5028 argblock = virtual_outgoing_args_rtx;
5030 else
5032 if (!PUSH_ARGS)
5033 argblock = push_block (gen_int_mode (args_size.constant, Pmode), 0, 0);
5036 /* We push args individually in reverse order, perform stack alignment
5037 before the first push (the last arg). */
5038 if (argblock == 0)
5039 anti_adjust_stack (gen_int_mode (args_size.constant
5040 - original_args_size.constant,
5041 Pmode));
5043 argnum = nargs - 1;
5045 #ifdef REG_PARM_STACK_SPACE
5046 if (ACCUMULATE_OUTGOING_ARGS)
5048 /* The argument list is the property of the called routine and it
5049 may clobber it. If the fixed area has been used for previous
5050 parameters, we must save and restore it. */
5051 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
5052 &low_to_save, &high_to_save);
5054 #endif
5056 /* When expanding a normal call, args are stored in push order,
5057 which is the reverse of what we have here. */
5058 bool any_regs = false;
5059 for (int i = nargs; i-- > 0; )
5060 if (argvec[i].reg != NULL_RTX)
5062 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
5063 any_regs = true;
5065 if (!any_regs)
5066 targetm.calls.call_args (pc_rtx, NULL_TREE);
5068 /* Push the args that need to be pushed. */
5070 have_push_fusage = false;
5072 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5073 are to be pushed. */
5074 for (count = 0; count < nargs; count++, argnum--)
5076 machine_mode mode = argvec[argnum].mode;
5077 rtx val = argvec[argnum].value;
5078 rtx reg = argvec[argnum].reg;
5079 int partial = argvec[argnum].partial;
5080 unsigned int parm_align = argvec[argnum].locate.boundary;
5081 poly_int64 lower_bound = 0, upper_bound = 0;
5083 if (! (reg != 0 && partial == 0))
5085 rtx use;
5087 if (ACCUMULATE_OUTGOING_ARGS)
5089 /* If this is being stored into a pre-allocated, fixed-size,
5090 stack area, save any previous data at that location. */
5092 if (ARGS_GROW_DOWNWARD)
5094 /* stack_slot is negative, but we want to index stack_usage_map
5095 with positive values. */
5096 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
5097 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
5099 else
5101 lower_bound = argvec[argnum].locate.slot_offset.constant;
5102 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
5105 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5106 reg_parm_stack_space))
5108 /* We need to make a save area. */
5109 poly_uint64 size
5110 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
5111 machine_mode save_mode
5112 = int_mode_for_size (size, 1).else_blk ();
5113 rtx adr
5114 = plus_constant (Pmode, argblock,
5115 argvec[argnum].locate.offset.constant);
5116 rtx stack_area
5117 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
5119 if (save_mode == BLKmode)
5121 argvec[argnum].save_area
5122 = assign_stack_temp (BLKmode,
5123 argvec[argnum].locate.size.constant
5126 emit_block_move (validize_mem
5127 (copy_rtx (argvec[argnum].save_area)),
5128 stack_area,
5129 (gen_int_mode
5130 (argvec[argnum].locate.size.constant,
5131 Pmode)),
5132 BLOCK_OP_CALL_PARM);
5134 else
5136 argvec[argnum].save_area = gen_reg_rtx (save_mode);
5138 emit_move_insn (argvec[argnum].save_area, stack_area);
5143 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
5144 partial, reg, 0, argblock,
5145 (gen_int_mode
5146 (argvec[argnum].locate.offset.constant, Pmode)),
5147 reg_parm_stack_space,
5148 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
5150 /* Now mark the segment we just used. */
5151 if (ACCUMULATE_OUTGOING_ARGS)
5152 mark_stack_region_used (lower_bound, upper_bound);
5154 NO_DEFER_POP;
5156 /* Indicate argument access so that alias.c knows that these
5157 values are live. */
5158 if (argblock)
5159 use = plus_constant (Pmode, argblock,
5160 argvec[argnum].locate.offset.constant);
5161 else if (have_push_fusage)
5162 continue;
5163 else
5165 /* When arguments are pushed, trying to tell alias.c where
5166 exactly this argument is won't work, because the
5167 auto-increment causes confusion. So we merely indicate
5168 that we access something with a known mode somewhere on
5169 the stack. */
5170 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
5171 gen_rtx_SCRATCH (Pmode));
5172 have_push_fusage = true;
5174 use = gen_rtx_MEM (argvec[argnum].mode, use);
5175 use = gen_rtx_USE (VOIDmode, use);
5176 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
5180 argnum = nargs - 1;
5182 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
5184 /* Now load any reg parms into their regs. */
5186 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5187 are to be pushed. */
5188 for (count = 0; count < nargs; count++, argnum--)
5190 machine_mode mode = argvec[argnum].mode;
5191 rtx val = argvec[argnum].value;
5192 rtx reg = argvec[argnum].reg;
5193 int partial = argvec[argnum].partial;
5195 /* Handle calls that pass values in multiple non-contiguous
5196 locations. The PA64 has examples of this for library calls. */
5197 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5198 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
5199 else if (reg != 0 && partial == 0)
5201 emit_move_insn (reg, val);
5202 #ifdef BLOCK_REG_PADDING
5203 poly_int64 size = GET_MODE_SIZE (argvec[argnum].mode);
5205 /* Copied from load_register_parameters. */
5207 /* Handle case where we have a value that needs shifting
5208 up to the msb. eg. a QImode value and we're padding
5209 upward on a BYTES_BIG_ENDIAN machine. */
5210 if (known_lt (size, UNITS_PER_WORD)
5211 && (argvec[argnum].locate.where_pad
5212 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5214 rtx x;
5215 poly_int64 shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
5217 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5218 report the whole reg as used. Strictly speaking, the
5219 call only uses SIZE bytes at the msb end, but it doesn't
5220 seem worth generating rtl to say that. */
5221 reg = gen_rtx_REG (word_mode, REGNO (reg));
5222 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
5223 if (x != reg)
5224 emit_move_insn (reg, x);
5226 #endif
5229 NO_DEFER_POP;
5232 /* Any regs containing parms remain in use through the call. */
5233 for (count = 0; count < nargs; count++)
5235 rtx reg = argvec[count].reg;
5236 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5237 use_group_regs (&call_fusage, reg);
5238 else if (reg != 0)
5240 int partial = argvec[count].partial;
5241 if (partial)
5243 int nregs;
5244 gcc_assert (partial % UNITS_PER_WORD == 0);
5245 nregs = partial / UNITS_PER_WORD;
5246 use_regs (&call_fusage, REGNO (reg), nregs);
5248 else
5249 use_reg (&call_fusage, reg);
5253 /* Pass the function the address in which to return a structure value. */
5254 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
5256 emit_move_insn (struct_value,
5257 force_reg (Pmode,
5258 force_operand (XEXP (mem_value, 0),
5259 NULL_RTX)));
5260 if (REG_P (struct_value))
5261 use_reg (&call_fusage, struct_value);
5264 /* Don't allow popping to be deferred, since then
5265 cse'ing of library calls could delete a call and leave the pop. */
5266 NO_DEFER_POP;
5267 valreg = (mem_value == 0 && outmode != VOIDmode
5268 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
5270 /* Stack must be properly aligned now. */
5271 gcc_assert (multiple_p (stack_pointer_delta,
5272 PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT));
5274 before_call = get_last_insn ();
5276 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5277 will set inhibit_defer_pop to that value. */
5278 /* The return type is needed to decide how many bytes the function pops.
5279 Signedness plays no role in that, so for simplicity, we pretend it's
5280 always signed. We also assume that the list of arguments passed has
5281 no impact, so we pretend it is unknown. */
5283 emit_call_1 (fun, NULL,
5284 get_identifier (XSTR (orgfun, 0)),
5285 build_function_type (tfom, NULL_TREE),
5286 original_args_size.constant, args_size.constant,
5287 struct_value_size,
5288 targetm.calls.function_arg (args_so_far,
5289 VOIDmode, void_type_node, true),
5290 valreg,
5291 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
5293 if (flag_ipa_ra)
5295 rtx datum = orgfun;
5296 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
5297 rtx_call_insn *last = last_call_insn ();
5298 add_reg_note (last, REG_CALL_DECL, datum);
5301 /* Right-shift returned value if necessary. */
5302 if (!pcc_struct_value
5303 && TYPE_MODE (tfom) != BLKmode
5304 && targetm.calls.return_in_msb (tfom))
5306 shift_return_value (TYPE_MODE (tfom), false, valreg);
5307 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5310 targetm.calls.end_call_args ();
5312 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5313 that it should complain if nonvolatile values are live. For
5314 functions that cannot return, inform flow that control does not
5315 fall through. */
5316 if (flags & ECF_NORETURN)
5318 /* The barrier note must be emitted
5319 immediately after the CALL_INSN. Some ports emit more than
5320 just a CALL_INSN above, so we must search for it here. */
5321 rtx_insn *last = get_last_insn ();
5322 while (!CALL_P (last))
5324 last = PREV_INSN (last);
5325 /* There was no CALL_INSN? */
5326 gcc_assert (last != before_call);
5329 emit_barrier_after (last);
5332 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5333 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5334 if (flags & ECF_NOTHROW)
5336 rtx_insn *last = get_last_insn ();
5337 while (!CALL_P (last))
5339 last = PREV_INSN (last);
5340 /* There was no CALL_INSN? */
5341 gcc_assert (last != before_call);
5344 make_reg_eh_region_note_nothrow_nononlocal (last);
5347 /* Now restore inhibit_defer_pop to its actual original value. */
5348 OK_DEFER_POP;
5350 pop_temp_slots ();
5352 /* Copy the value to the right place. */
5353 if (outmode != VOIDmode && retval)
5355 if (mem_value)
5357 if (value == 0)
5358 value = mem_value;
5359 if (value != mem_value)
5360 emit_move_insn (value, mem_value);
5362 else if (GET_CODE (valreg) == PARALLEL)
5364 if (value == 0)
5365 value = gen_reg_rtx (outmode);
5366 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5368 else
5370 /* Convert to the proper mode if a promotion has been active. */
5371 if (GET_MODE (valreg) != outmode)
5373 int unsignedp = TYPE_UNSIGNED (tfom);
5375 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5376 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5377 == GET_MODE (valreg));
5378 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5381 if (value != 0)
5382 emit_move_insn (value, valreg);
5383 else
5384 value = valreg;
5388 if (ACCUMULATE_OUTGOING_ARGS)
5390 #ifdef REG_PARM_STACK_SPACE
5391 if (save_area)
5392 restore_fixed_argument_area (save_area, argblock,
5393 high_to_save, low_to_save);
5394 #endif
5396 /* If we saved any argument areas, restore them. */
5397 for (count = 0; count < nargs; count++)
5398 if (argvec[count].save_area)
5400 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5401 rtx adr = plus_constant (Pmode, argblock,
5402 argvec[count].locate.offset.constant);
5403 rtx stack_area = gen_rtx_MEM (save_mode,
5404 memory_address (save_mode, adr));
5406 if (save_mode == BLKmode)
5407 emit_block_move (stack_area,
5408 validize_mem
5409 (copy_rtx (argvec[count].save_area)),
5410 (gen_int_mode
5411 (argvec[count].locate.size.constant, Pmode)),
5412 BLOCK_OP_CALL_PARM);
5413 else
5414 emit_move_insn (stack_area, argvec[count].save_area);
5417 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5418 stack_usage_map = initial_stack_usage_map;
5419 stack_usage_watermark = initial_stack_usage_watermark;
5422 free (stack_usage_map_buf);
5424 return value;
5429 /* Store pointer bounds argument ARG into Bounds Table entry
5430 associated with PARM. */
5431 static void
5432 store_bounds (struct arg_data *arg, struct arg_data *parm)
5434 rtx slot = NULL, ptr = NULL, addr = NULL;
5436 /* We may pass bounds not associated with any pointer. */
5437 if (!parm)
5439 gcc_assert (arg->special_slot);
5440 slot = arg->special_slot;
5441 ptr = const0_rtx;
5443 /* Find pointer associated with bounds and where it is
5444 passed. */
5445 else
5447 if (!parm->reg)
5449 gcc_assert (!arg->special_slot);
5451 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5453 else if (REG_P (parm->reg))
5455 gcc_assert (arg->special_slot);
5456 slot = arg->special_slot;
5458 if (MEM_P (parm->value))
5459 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5460 else if (REG_P (parm->value))
5461 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5462 else
5464 gcc_assert (!arg->pointer_offset);
5465 ptr = parm->value;
5468 else
5470 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5472 gcc_assert (arg->special_slot);
5473 slot = arg->special_slot;
5475 if (parm->parallel_value)
5476 ptr = chkp_get_value_with_offs (parm->parallel_value,
5477 GEN_INT (arg->pointer_offset));
5478 else
5479 gcc_unreachable ();
5483 /* Expand bounds. */
5484 if (!arg->value)
5485 arg->value = expand_normal (arg->tree_value);
5487 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5490 /* Store a single argument for a function call
5491 into the register or memory area where it must be passed.
5492 *ARG describes the argument value and where to pass it.
5494 ARGBLOCK is the address of the stack-block for all the arguments,
5495 or 0 on a machine where arguments are pushed individually.
5497 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5498 so must be careful about how the stack is used.
5500 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5501 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5502 that we need not worry about saving and restoring the stack.
5504 FNDECL is the declaration of the function we are calling.
5506 Return nonzero if this arg should cause sibcall failure,
5507 zero otherwise. */
5509 static int
5510 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5511 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5513 tree pval = arg->tree_value;
5514 rtx reg = 0;
5515 int partial = 0;
5516 poly_int64 used = 0;
5517 poly_int64 lower_bound = 0, upper_bound = 0;
5518 int sibcall_failure = 0;
5520 if (TREE_CODE (pval) == ERROR_MARK)
5521 return 1;
5523 /* Push a new temporary level for any temporaries we make for
5524 this argument. */
5525 push_temp_slots ();
5527 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5529 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5530 save any previous data at that location. */
5531 if (argblock && ! variable_size && arg->stack)
5533 if (ARGS_GROW_DOWNWARD)
5535 /* stack_slot is negative, but we want to index stack_usage_map
5536 with positive values. */
5537 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5539 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5540 upper_bound = -rtx_to_poly_int64 (offset) + 1;
5542 else
5543 upper_bound = 0;
5545 lower_bound = upper_bound - arg->locate.size.constant;
5547 else
5549 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5551 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5552 lower_bound = rtx_to_poly_int64 (offset);
5554 else
5555 lower_bound = 0;
5557 upper_bound = lower_bound + arg->locate.size.constant;
5560 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5561 reg_parm_stack_space))
5563 /* We need to make a save area. */
5564 poly_uint64 size = arg->locate.size.constant * BITS_PER_UNIT;
5565 machine_mode save_mode
5566 = int_mode_for_size (size, 1).else_blk ();
5567 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5568 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5570 if (save_mode == BLKmode)
5572 arg->save_area
5573 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5574 preserve_temp_slots (arg->save_area);
5575 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5576 stack_area,
5577 (gen_int_mode
5578 (arg->locate.size.constant, Pmode)),
5579 BLOCK_OP_CALL_PARM);
5581 else
5583 arg->save_area = gen_reg_rtx (save_mode);
5584 emit_move_insn (arg->save_area, stack_area);
5590 /* If this isn't going to be placed on both the stack and in registers,
5591 set up the register and number of words. */
5592 if (! arg->pass_on_stack)
5594 if (flags & ECF_SIBCALL)
5595 reg = arg->tail_call_reg;
5596 else
5597 reg = arg->reg;
5598 partial = arg->partial;
5601 /* Being passed entirely in a register. We shouldn't be called in
5602 this case. */
5603 gcc_assert (reg == 0 || partial != 0);
5605 /* If this arg needs special alignment, don't load the registers
5606 here. */
5607 if (arg->n_aligned_regs != 0)
5608 reg = 0;
5610 /* If this is being passed partially in a register, we can't evaluate
5611 it directly into its stack slot. Otherwise, we can. */
5612 if (arg->value == 0)
5614 /* stack_arg_under_construction is nonzero if a function argument is
5615 being evaluated directly into the outgoing argument list and
5616 expand_call must take special action to preserve the argument list
5617 if it is called recursively.
5619 For scalar function arguments stack_usage_map is sufficient to
5620 determine which stack slots must be saved and restored. Scalar
5621 arguments in general have pass_on_stack == 0.
5623 If this argument is initialized by a function which takes the
5624 address of the argument (a C++ constructor or a C function
5625 returning a BLKmode structure), then stack_usage_map is
5626 insufficient and expand_call must push the stack around the
5627 function call. Such arguments have pass_on_stack == 1.
5629 Note that it is always safe to set stack_arg_under_construction,
5630 but this generates suboptimal code if set when not needed. */
5632 if (arg->pass_on_stack)
5633 stack_arg_under_construction++;
5635 arg->value = expand_expr (pval,
5636 (partial
5637 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5638 ? NULL_RTX : arg->stack,
5639 VOIDmode, EXPAND_STACK_PARM);
5641 /* If we are promoting object (or for any other reason) the mode
5642 doesn't agree, convert the mode. */
5644 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5645 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5646 arg->value, arg->unsignedp);
5648 if (arg->pass_on_stack)
5649 stack_arg_under_construction--;
5652 /* Check for overlap with already clobbered argument area. */
5653 if ((flags & ECF_SIBCALL)
5654 && MEM_P (arg->value)
5655 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg->value, 0),
5656 arg->locate.size.constant))
5657 sibcall_failure = 1;
5659 /* Don't allow anything left on stack from computation
5660 of argument to alloca. */
5661 if (flags & ECF_MAY_BE_ALLOCA)
5662 do_pending_stack_adjust ();
5664 if (arg->value == arg->stack)
5665 /* If the value is already in the stack slot, we are done. */
5667 else if (arg->mode != BLKmode)
5669 unsigned int parm_align;
5671 /* Argument is a scalar, not entirely passed in registers.
5672 (If part is passed in registers, arg->partial says how much
5673 and emit_push_insn will take care of putting it there.)
5675 Push it, and if its size is less than the
5676 amount of space allocated to it,
5677 also bump stack pointer by the additional space.
5678 Note that in C the default argument promotions
5679 will prevent such mismatches. */
5681 poly_int64 size = (TYPE_EMPTY_P (TREE_TYPE (pval))
5682 ? 0 : GET_MODE_SIZE (arg->mode));
5684 /* Compute how much space the push instruction will push.
5685 On many machines, pushing a byte will advance the stack
5686 pointer by a halfword. */
5687 #ifdef PUSH_ROUNDING
5688 size = PUSH_ROUNDING (size);
5689 #endif
5690 used = size;
5692 /* Compute how much space the argument should get:
5693 round up to a multiple of the alignment for arguments. */
5694 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5695 != PAD_NONE)
5696 /* At the moment we don't (need to) support ABIs for which the
5697 padding isn't known at compile time. In principle it should
5698 be easy to add though. */
5699 used = force_align_up (size, PARM_BOUNDARY / BITS_PER_UNIT);
5701 /* Compute the alignment of the pushed argument. */
5702 parm_align = arg->locate.boundary;
5703 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5704 == PAD_DOWNWARD)
5706 poly_int64 pad = used - size;
5707 unsigned int pad_align = known_alignment (pad) * BITS_PER_UNIT;
5708 if (pad_align != 0)
5709 parm_align = MIN (parm_align, pad_align);
5712 /* This isn't already where we want it on the stack, so put it there.
5713 This can either be done with push or copy insns. */
5714 if (maybe_ne (used, 0)
5715 && !emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval),
5716 NULL_RTX, parm_align, partial, reg, used - size,
5717 argblock, ARGS_SIZE_RTX (arg->locate.offset),
5718 reg_parm_stack_space,
5719 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5720 sibcall_failure = 1;
5722 /* Unless this is a partially-in-register argument, the argument is now
5723 in the stack. */
5724 if (partial == 0)
5725 arg->value = arg->stack;
5727 else
5729 /* BLKmode, at least partly to be pushed. */
5731 unsigned int parm_align;
5732 poly_int64 excess;
5733 rtx size_rtx;
5735 /* Pushing a nonscalar.
5736 If part is passed in registers, PARTIAL says how much
5737 and emit_push_insn will take care of putting it there. */
5739 /* Round its size up to a multiple
5740 of the allocation unit for arguments. */
5742 if (arg->locate.size.var != 0)
5744 excess = 0;
5745 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5747 else
5749 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5750 for BLKmode is careful to avoid it. */
5751 excess = (arg->locate.size.constant
5752 - arg_int_size_in_bytes (TREE_TYPE (pval))
5753 + partial);
5754 size_rtx = expand_expr (arg_size_in_bytes (TREE_TYPE (pval)),
5755 NULL_RTX, TYPE_MODE (sizetype),
5756 EXPAND_NORMAL);
5759 parm_align = arg->locate.boundary;
5761 /* When an argument is padded down, the block is aligned to
5762 PARM_BOUNDARY, but the actual argument isn't. */
5763 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5764 == PAD_DOWNWARD)
5766 if (arg->locate.size.var)
5767 parm_align = BITS_PER_UNIT;
5768 else
5770 unsigned int excess_align
5771 = known_alignment (excess) * BITS_PER_UNIT;
5772 if (excess_align != 0)
5773 parm_align = MIN (parm_align, excess_align);
5777 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5779 /* emit_push_insn might not work properly if arg->value and
5780 argblock + arg->locate.offset areas overlap. */
5781 rtx x = arg->value;
5782 poly_int64 i = 0;
5784 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5785 || (GET_CODE (XEXP (x, 0)) == PLUS
5786 && XEXP (XEXP (x, 0), 0) ==
5787 crtl->args.internal_arg_pointer
5788 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5790 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5791 i = rtx_to_poly_int64 (XEXP (XEXP (x, 0), 1));
5793 /* arg.locate doesn't contain the pretend_args_size offset,
5794 it's part of argblock. Ensure we don't count it in I. */
5795 if (STACK_GROWS_DOWNWARD)
5796 i -= crtl->args.pretend_args_size;
5797 else
5798 i += crtl->args.pretend_args_size;
5800 /* expand_call should ensure this. */
5801 gcc_assert (!arg->locate.offset.var
5802 && arg->locate.size.var == 0);
5803 poly_int64 size_val = rtx_to_poly_int64 (size_rtx);
5805 if (known_eq (arg->locate.offset.constant, i))
5807 /* Even though they appear to be at the same location,
5808 if part of the outgoing argument is in registers,
5809 they aren't really at the same location. Check for
5810 this by making sure that the incoming size is the
5811 same as the outgoing size. */
5812 if (maybe_ne (arg->locate.size.constant, size_val))
5813 sibcall_failure = 1;
5815 else if (maybe_in_range_p (arg->locate.offset.constant,
5816 i, size_val))
5817 sibcall_failure = 1;
5818 /* Use arg->locate.size.constant instead of size_rtx
5819 because we only care about the part of the argument
5820 on the stack. */
5821 else if (maybe_in_range_p (i, arg->locate.offset.constant,
5822 arg->locate.size.constant))
5823 sibcall_failure = 1;
5827 if (!CONST_INT_P (size_rtx) || INTVAL (size_rtx) != 0)
5828 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5829 parm_align, partial, reg, excess, argblock,
5830 ARGS_SIZE_RTX (arg->locate.offset),
5831 reg_parm_stack_space,
5832 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5834 /* Unless this is a partially-in-register argument, the argument is now
5835 in the stack.
5837 ??? Unlike the case above, in which we want the actual
5838 address of the data, so that we can load it directly into a
5839 register, here we want the address of the stack slot, so that
5840 it's properly aligned for word-by-word copying or something
5841 like that. It's not clear that this is always correct. */
5842 if (partial == 0)
5843 arg->value = arg->stack_slot;
5846 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5848 tree type = TREE_TYPE (arg->tree_value);
5849 arg->parallel_value
5850 = emit_group_load_into_temps (arg->reg, arg->value, type,
5851 int_size_in_bytes (type));
5854 /* Mark all slots this store used. */
5855 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5856 && argblock && ! variable_size && arg->stack)
5857 mark_stack_region_used (lower_bound, upper_bound);
5859 /* Once we have pushed something, pops can't safely
5860 be deferred during the rest of the arguments. */
5861 NO_DEFER_POP;
5863 /* Free any temporary slots made in processing this argument. */
5864 pop_temp_slots ();
5866 return sibcall_failure;
5869 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5871 bool
5872 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5873 const_tree type)
5875 if (!type)
5876 return false;
5878 /* If the type has variable size... */
5879 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5880 return true;
5882 /* If the type is marked as addressable (it is required
5883 to be constructed into the stack)... */
5884 if (TREE_ADDRESSABLE (type))
5885 return true;
5887 return false;
5890 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5891 takes trailing padding of a structure into account. */
5892 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5894 bool
5895 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5897 if (!type)
5898 return false;
5900 /* If the type has variable size... */
5901 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5902 return true;
5904 /* If the type is marked as addressable (it is required
5905 to be constructed into the stack)... */
5906 if (TREE_ADDRESSABLE (type))
5907 return true;
5909 if (TYPE_EMPTY_P (type))
5910 return false;
5912 /* If the padding and mode of the type is such that a copy into
5913 a register would put it into the wrong part of the register. */
5914 if (mode == BLKmode
5915 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5916 && (targetm.calls.function_arg_padding (mode, type)
5917 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5918 return true;
5920 return false;
5923 /* Tell the garbage collector about GTY markers in this source file. */
5924 #include "gt-calls.h"