PR testsuite/85483: Move aarch64/sve/vcond_1.c test to g++.dg/other/
[official-gcc.git] / gcc / calls.c
blob9eb0467311b2967a373c20013447dd738ddb4f61
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 gimple_call_num_args (stmt) > 0;
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 /* If rettype is addressable, we may not create a temporary.
3426 If target is properly aligned at runtime and the compiler
3427 just doesn't know about it, it will work fine, otherwise it
3428 will be UB. */
3429 && (TREE_ADDRESSABLE (rettype)
3430 || !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3431 && targetm.slow_unaligned_access (TYPE_MODE (rettype),
3432 MEM_ALIGN (target)))))
3433 structure_value_addr = XEXP (target, 0);
3434 else
3436 /* For variable-sized objects, we must be called with a target
3437 specified. If we were to allocate space on the stack here,
3438 we would have no way of knowing when to free it. */
3439 rtx d = assign_temp (rettype, 1, 1);
3440 structure_value_addr = XEXP (d, 0);
3441 target = 0;
3444 #endif /* not PCC_STATIC_STRUCT_RETURN */
3447 /* Figure out the amount to which the stack should be aligned. */
3448 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3449 if (fndecl)
3451 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3452 /* Without automatic stack alignment, we can't increase preferred
3453 stack boundary. With automatic stack alignment, it is
3454 unnecessary since unless we can guarantee that all callers will
3455 align the outgoing stack properly, callee has to align its
3456 stack anyway. */
3457 if (i
3458 && i->preferred_incoming_stack_boundary
3459 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3460 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3463 /* Operand 0 is a pointer-to-function; get the type of the function. */
3464 funtype = TREE_TYPE (addr);
3465 gcc_assert (POINTER_TYPE_P (funtype));
3466 funtype = TREE_TYPE (funtype);
3468 /* Count whether there are actual complex arguments that need to be split
3469 into their real and imaginary parts. Munge the type_arg_types
3470 appropriately here as well. */
3471 if (targetm.calls.split_complex_arg)
3473 call_expr_arg_iterator iter;
3474 tree arg;
3475 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3477 tree type = TREE_TYPE (arg);
3478 if (type && TREE_CODE (type) == COMPLEX_TYPE
3479 && targetm.calls.split_complex_arg (type))
3480 num_complex_actuals++;
3482 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3484 else
3485 type_arg_types = TYPE_ARG_TYPES (funtype);
3487 if (flags & ECF_MAY_BE_ALLOCA)
3488 cfun->calls_alloca = 1;
3490 /* If struct_value_rtx is 0, it means pass the address
3491 as if it were an extra parameter. Put the argument expression
3492 in structure_value_addr_value. */
3493 if (structure_value_addr && struct_value == 0)
3495 /* If structure_value_addr is a REG other than
3496 virtual_outgoing_args_rtx, we can use always use it. If it
3497 is not a REG, we must always copy it into a register.
3498 If it is virtual_outgoing_args_rtx, we must copy it to another
3499 register in some cases. */
3500 rtx temp = (!REG_P (structure_value_addr)
3501 || (ACCUMULATE_OUTGOING_ARGS
3502 && stack_arg_under_construction
3503 && structure_value_addr == virtual_outgoing_args_rtx)
3504 ? copy_addr_to_reg (convert_memory_address
3505 (Pmode, structure_value_addr))
3506 : structure_value_addr);
3508 structure_value_addr_value =
3509 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3510 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3513 /* Count the arguments and set NUM_ACTUALS. */
3514 num_actuals =
3515 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3517 /* Compute number of named args.
3518 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3520 if (type_arg_types != 0)
3521 n_named_args
3522 = (list_length (type_arg_types)
3523 /* Count the struct value address, if it is passed as a parm. */
3524 + structure_value_addr_parm);
3525 else
3526 /* If we know nothing, treat all args as named. */
3527 n_named_args = num_actuals;
3529 /* Start updating where the next arg would go.
3531 On some machines (such as the PA) indirect calls have a different
3532 calling convention than normal calls. The fourth argument in
3533 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3534 or not. */
3535 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3536 args_so_far = pack_cumulative_args (&args_so_far_v);
3538 /* Now possibly adjust the number of named args.
3539 Normally, don't include the last named arg if anonymous args follow.
3540 We do include the last named arg if
3541 targetm.calls.strict_argument_naming() returns nonzero.
3542 (If no anonymous args follow, the result of list_length is actually
3543 one too large. This is harmless.)
3545 If targetm.calls.pretend_outgoing_varargs_named() returns
3546 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3547 this machine will be able to place unnamed args that were passed
3548 in registers into the stack. So treat all args as named. This
3549 allows the insns emitting for a specific argument list to be
3550 independent of the function declaration.
3552 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3553 we do not have any reliable way to pass unnamed args in
3554 registers, so we must force them into memory. */
3556 if (type_arg_types != 0
3557 && targetm.calls.strict_argument_naming (args_so_far))
3559 else if (type_arg_types != 0
3560 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3561 /* Don't include the last named arg. */
3562 --n_named_args;
3563 else
3564 /* Treat all args as named. */
3565 n_named_args = num_actuals;
3567 /* Make a vector to hold all the information about each arg. */
3568 args = XCNEWVEC (struct arg_data, num_actuals);
3570 /* Build up entries in the ARGS array, compute the size of the
3571 arguments into ARGS_SIZE, etc. */
3572 initialize_argument_information (num_actuals, args, &args_size,
3573 n_named_args, exp,
3574 structure_value_addr_value, fndecl, fntype,
3575 args_so_far, reg_parm_stack_space,
3576 &old_stack_level, &old_pending_adj,
3577 &must_preallocate, &flags,
3578 &try_tail_call, CALL_FROM_THUNK_P (exp));
3580 if (args_size.var)
3581 must_preallocate = 1;
3583 /* Now make final decision about preallocating stack space. */
3584 must_preallocate = finalize_must_preallocate (must_preallocate,
3585 num_actuals, args,
3586 &args_size);
3588 /* If the structure value address will reference the stack pointer, we
3589 must stabilize it. We don't need to do this if we know that we are
3590 not going to adjust the stack pointer in processing this call. */
3592 if (structure_value_addr
3593 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3594 || reg_mentioned_p (virtual_outgoing_args_rtx,
3595 structure_value_addr))
3596 && (args_size.var
3597 || (!ACCUMULATE_OUTGOING_ARGS
3598 && maybe_ne (args_size.constant, 0))))
3599 structure_value_addr = copy_to_reg (structure_value_addr);
3601 /* Tail calls can make things harder to debug, and we've traditionally
3602 pushed these optimizations into -O2. Don't try if we're already
3603 expanding a call, as that means we're an argument. Don't try if
3604 there's cleanups, as we know there's code to follow the call. */
3606 if (currently_expanding_call++ != 0
3607 || !flag_optimize_sibling_calls
3608 || args_size.var
3609 || dbg_cnt (tail_call) == false)
3610 try_tail_call = 0;
3612 /* If the user has marked the function as requiring tail-call
3613 optimization, attempt it. */
3614 if (must_tail_call)
3615 try_tail_call = 1;
3617 /* Rest of purposes for tail call optimizations to fail. */
3618 if (try_tail_call)
3619 try_tail_call = can_implement_as_sibling_call_p (exp,
3620 structure_value_addr,
3621 funtype,
3622 reg_parm_stack_space,
3623 fndecl,
3624 flags, addr, args_size);
3626 /* Check if caller and callee disagree in promotion of function
3627 return value. */
3628 if (try_tail_call)
3630 machine_mode caller_mode, caller_promoted_mode;
3631 machine_mode callee_mode, callee_promoted_mode;
3632 int caller_unsignedp, callee_unsignedp;
3633 tree caller_res = DECL_RESULT (current_function_decl);
3635 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3636 caller_mode = DECL_MODE (caller_res);
3637 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3638 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3639 caller_promoted_mode
3640 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3641 &caller_unsignedp,
3642 TREE_TYPE (current_function_decl), 1);
3643 callee_promoted_mode
3644 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3645 &callee_unsignedp,
3646 funtype, 1);
3647 if (caller_mode != VOIDmode
3648 && (caller_promoted_mode != callee_promoted_mode
3649 || ((caller_mode != caller_promoted_mode
3650 || callee_mode != callee_promoted_mode)
3651 && (caller_unsignedp != callee_unsignedp
3652 || partial_subreg_p (caller_mode, callee_mode)))))
3654 try_tail_call = 0;
3655 maybe_complain_about_tail_call (exp,
3656 "caller and callee disagree in"
3657 " promotion of function"
3658 " return value");
3662 /* Ensure current function's preferred stack boundary is at least
3663 what we need. Stack alignment may also increase preferred stack
3664 boundary. */
3665 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3666 crtl->preferred_stack_boundary = preferred_stack_boundary;
3667 else
3668 preferred_stack_boundary = crtl->preferred_stack_boundary;
3670 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3672 /* We want to make two insn chains; one for a sibling call, the other
3673 for a normal call. We will select one of the two chains after
3674 initial RTL generation is complete. */
3675 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3677 int sibcall_failure = 0;
3678 /* We want to emit any pending stack adjustments before the tail
3679 recursion "call". That way we know any adjustment after the tail
3680 recursion call can be ignored if we indeed use the tail
3681 call expansion. */
3682 saved_pending_stack_adjust save;
3683 rtx_insn *insns, *before_call, *after_args;
3684 rtx next_arg_reg;
3686 if (pass == 0)
3688 /* State variables we need to save and restore between
3689 iterations. */
3690 save_pending_stack_adjust (&save);
3692 if (pass)
3693 flags &= ~ECF_SIBCALL;
3694 else
3695 flags |= ECF_SIBCALL;
3697 /* Other state variables that we must reinitialize each time
3698 through the loop (that are not initialized by the loop itself). */
3699 argblock = 0;
3700 call_fusage = 0;
3702 /* Start a new sequence for the normal call case.
3704 From this point on, if the sibling call fails, we want to set
3705 sibcall_failure instead of continuing the loop. */
3706 start_sequence ();
3708 /* Don't let pending stack adjusts add up to too much.
3709 Also, do all pending adjustments now if there is any chance
3710 this might be a call to alloca or if we are expanding a sibling
3711 call sequence.
3712 Also do the adjustments before a throwing call, otherwise
3713 exception handling can fail; PR 19225. */
3714 if (maybe_ge (pending_stack_adjust, 32)
3715 || (maybe_ne (pending_stack_adjust, 0)
3716 && (flags & ECF_MAY_BE_ALLOCA))
3717 || (maybe_ne (pending_stack_adjust, 0)
3718 && flag_exceptions && !(flags & ECF_NOTHROW))
3719 || pass == 0)
3720 do_pending_stack_adjust ();
3722 /* Precompute any arguments as needed. */
3723 if (pass)
3724 precompute_arguments (num_actuals, args);
3726 /* Now we are about to start emitting insns that can be deleted
3727 if a libcall is deleted. */
3728 if (pass && (flags & ECF_MALLOC))
3729 start_sequence ();
3731 if (pass == 0
3732 && crtl->stack_protect_guard
3733 && targetm.stack_protect_runtime_enabled_p ())
3734 stack_protect_epilogue ();
3736 adjusted_args_size = args_size;
3737 /* Compute the actual size of the argument block required. The variable
3738 and constant sizes must be combined, the size may have to be rounded,
3739 and there may be a minimum required size. When generating a sibcall
3740 pattern, do not round up, since we'll be re-using whatever space our
3741 caller provided. */
3742 unadjusted_args_size
3743 = compute_argument_block_size (reg_parm_stack_space,
3744 &adjusted_args_size,
3745 fndecl, fntype,
3746 (pass == 0 ? 0
3747 : preferred_stack_boundary));
3749 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3751 /* The argument block when performing a sibling call is the
3752 incoming argument block. */
3753 if (pass == 0)
3755 argblock = crtl->args.internal_arg_pointer;
3756 if (STACK_GROWS_DOWNWARD)
3757 argblock
3758 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3759 else
3760 argblock
3761 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3763 HOST_WIDE_INT map_size = constant_lower_bound (args_size.constant);
3764 stored_args_map = sbitmap_alloc (map_size);
3765 bitmap_clear (stored_args_map);
3766 stored_args_watermark = HOST_WIDE_INT_M1U;
3769 /* If we have no actual push instructions, or shouldn't use them,
3770 make space for all args right now. */
3771 else if (adjusted_args_size.var != 0)
3773 if (old_stack_level == 0)
3775 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3776 old_stack_pointer_delta = stack_pointer_delta;
3777 old_pending_adj = pending_stack_adjust;
3778 pending_stack_adjust = 0;
3779 /* stack_arg_under_construction says whether a stack arg is
3780 being constructed at the old stack level. Pushing the stack
3781 gets a clean outgoing argument block. */
3782 old_stack_arg_under_construction = stack_arg_under_construction;
3783 stack_arg_under_construction = 0;
3785 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3786 if (flag_stack_usage_info)
3787 current_function_has_unbounded_dynamic_stack_size = 1;
3789 else
3791 /* Note that we must go through the motions of allocating an argument
3792 block even if the size is zero because we may be storing args
3793 in the area reserved for register arguments, which may be part of
3794 the stack frame. */
3796 poly_int64 needed = adjusted_args_size.constant;
3798 /* Store the maximum argument space used. It will be pushed by
3799 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3800 checking). */
3802 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
3803 needed);
3805 if (must_preallocate)
3807 if (ACCUMULATE_OUTGOING_ARGS)
3809 /* Since the stack pointer will never be pushed, it is
3810 possible for the evaluation of a parm to clobber
3811 something we have already written to the stack.
3812 Since most function calls on RISC machines do not use
3813 the stack, this is uncommon, but must work correctly.
3815 Therefore, we save any area of the stack that was already
3816 written and that we are using. Here we set up to do this
3817 by making a new stack usage map from the old one. The
3818 actual save will be done by store_one_arg.
3820 Another approach might be to try to reorder the argument
3821 evaluations to avoid this conflicting stack usage. */
3823 /* Since we will be writing into the entire argument area,
3824 the map must be allocated for its entire size, not just
3825 the part that is the responsibility of the caller. */
3826 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3827 needed += reg_parm_stack_space;
3829 poly_int64 limit = needed;
3830 if (ARGS_GROW_DOWNWARD)
3831 limit += 1;
3833 /* For polynomial sizes, this is the maximum possible
3834 size needed for arguments with a constant size
3835 and offset. */
3836 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
3837 highest_outgoing_arg_in_use
3838 = MAX (initial_highest_arg_in_use, const_limit);
3840 free (stack_usage_map_buf);
3841 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3842 stack_usage_map = stack_usage_map_buf;
3844 if (initial_highest_arg_in_use)
3845 memcpy (stack_usage_map, initial_stack_usage_map,
3846 initial_highest_arg_in_use);
3848 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3849 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3850 (highest_outgoing_arg_in_use
3851 - initial_highest_arg_in_use));
3852 needed = 0;
3854 /* The address of the outgoing argument list must not be
3855 copied to a register here, because argblock would be left
3856 pointing to the wrong place after the call to
3857 allocate_dynamic_stack_space below. */
3859 argblock = virtual_outgoing_args_rtx;
3861 else
3863 /* Try to reuse some or all of the pending_stack_adjust
3864 to get this space. */
3865 if (inhibit_defer_pop == 0
3866 && (combine_pending_stack_adjustment_and_call
3867 (&needed,
3868 unadjusted_args_size,
3869 &adjusted_args_size,
3870 preferred_unit_stack_boundary)))
3872 /* combine_pending_stack_adjustment_and_call computes
3873 an adjustment before the arguments are allocated.
3874 Account for them and see whether or not the stack
3875 needs to go up or down. */
3876 needed = unadjusted_args_size - needed;
3878 /* Checked by
3879 combine_pending_stack_adjustment_and_call. */
3880 gcc_checking_assert (ordered_p (needed, 0));
3881 if (maybe_lt (needed, 0))
3883 /* We're releasing stack space. */
3884 /* ??? We can avoid any adjustment at all if we're
3885 already aligned. FIXME. */
3886 pending_stack_adjust = -needed;
3887 do_pending_stack_adjust ();
3888 needed = 0;
3890 else
3891 /* We need to allocate space. We'll do that in
3892 push_block below. */
3893 pending_stack_adjust = 0;
3896 /* Special case this because overhead of `push_block' in
3897 this case is non-trivial. */
3898 if (known_eq (needed, 0))
3899 argblock = virtual_outgoing_args_rtx;
3900 else
3902 rtx needed_rtx = gen_int_mode (needed, Pmode);
3903 argblock = push_block (needed_rtx, 0, 0);
3904 if (ARGS_GROW_DOWNWARD)
3905 argblock = plus_constant (Pmode, argblock, needed);
3908 /* We only really need to call `copy_to_reg' in the case
3909 where push insns are going to be used to pass ARGBLOCK
3910 to a function call in ARGS. In that case, the stack
3911 pointer changes value from the allocation point to the
3912 call point, and hence the value of
3913 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3914 as well always do it. */
3915 argblock = copy_to_reg (argblock);
3920 if (ACCUMULATE_OUTGOING_ARGS)
3922 /* The save/restore code in store_one_arg handles all
3923 cases except one: a constructor call (including a C
3924 function returning a BLKmode struct) to initialize
3925 an argument. */
3926 if (stack_arg_under_construction)
3928 rtx push_size
3929 = (gen_int_mode
3930 (adjusted_args_size.constant
3931 + (OUTGOING_REG_PARM_STACK_SPACE (!fndecl ? fntype
3932 : TREE_TYPE (fndecl))
3933 ? 0 : reg_parm_stack_space), Pmode));
3934 if (old_stack_level == 0)
3936 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3937 old_stack_pointer_delta = stack_pointer_delta;
3938 old_pending_adj = pending_stack_adjust;
3939 pending_stack_adjust = 0;
3940 /* stack_arg_under_construction says whether a stack
3941 arg is being constructed at the old stack level.
3942 Pushing the stack gets a clean outgoing argument
3943 block. */
3944 old_stack_arg_under_construction
3945 = stack_arg_under_construction;
3946 stack_arg_under_construction = 0;
3947 /* Make a new map for the new argument list. */
3948 free (stack_usage_map_buf);
3949 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3950 stack_usage_map = stack_usage_map_buf;
3951 highest_outgoing_arg_in_use = 0;
3952 stack_usage_watermark = HOST_WIDE_INT_M1U;
3954 /* We can pass TRUE as the 4th argument because we just
3955 saved the stack pointer and will restore it right after
3956 the call. */
3957 allocate_dynamic_stack_space (push_size, 0, BIGGEST_ALIGNMENT,
3958 -1, true);
3961 /* If argument evaluation might modify the stack pointer,
3962 copy the address of the argument list to a register. */
3963 for (i = 0; i < num_actuals; i++)
3964 if (args[i].pass_on_stack)
3966 argblock = copy_addr_to_reg (argblock);
3967 break;
3971 compute_argument_addresses (args, argblock, num_actuals);
3973 /* Stack is properly aligned, pops can't safely be deferred during
3974 the evaluation of the arguments. */
3975 NO_DEFER_POP;
3977 /* Precompute all register parameters. It isn't safe to compute
3978 anything once we have started filling any specific hard regs.
3979 TLS symbols sometimes need a call to resolve. Precompute
3980 register parameters before any stack pointer manipulation
3981 to avoid unaligned stack in the called function. */
3982 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3984 OK_DEFER_POP;
3986 /* Perform stack alignment before the first push (the last arg). */
3987 if (argblock == 0
3988 && maybe_gt (adjusted_args_size.constant, reg_parm_stack_space)
3989 && maybe_ne (adjusted_args_size.constant, unadjusted_args_size))
3991 /* When the stack adjustment is pending, we get better code
3992 by combining the adjustments. */
3993 if (maybe_ne (pending_stack_adjust, 0)
3994 && ! inhibit_defer_pop
3995 && (combine_pending_stack_adjustment_and_call
3996 (&pending_stack_adjust,
3997 unadjusted_args_size,
3998 &adjusted_args_size,
3999 preferred_unit_stack_boundary)))
4000 do_pending_stack_adjust ();
4001 else if (argblock == 0)
4002 anti_adjust_stack (gen_int_mode (adjusted_args_size.constant
4003 - unadjusted_args_size,
4004 Pmode));
4006 /* Now that the stack is properly aligned, pops can't safely
4007 be deferred during the evaluation of the arguments. */
4008 NO_DEFER_POP;
4010 /* Record the maximum pushed stack space size. We need to delay
4011 doing it this far to take into account the optimization done
4012 by combine_pending_stack_adjustment_and_call. */
4013 if (flag_stack_usage_info
4014 && !ACCUMULATE_OUTGOING_ARGS
4015 && pass
4016 && adjusted_args_size.var == 0)
4018 poly_int64 pushed = (adjusted_args_size.constant
4019 + pending_stack_adjust);
4020 current_function_pushed_stack_size
4021 = upper_bound (current_function_pushed_stack_size, pushed);
4024 funexp = rtx_for_function_call (fndecl, addr);
4026 if (CALL_EXPR_STATIC_CHAIN (exp))
4027 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
4028 else
4029 static_chain_value = 0;
4031 #ifdef REG_PARM_STACK_SPACE
4032 /* Save the fixed argument area if it's part of the caller's frame and
4033 is clobbered by argument setup for this call. */
4034 if (ACCUMULATE_OUTGOING_ARGS && pass)
4035 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4036 &low_to_save, &high_to_save);
4037 #endif
4039 /* Now store (and compute if necessary) all non-register parms.
4040 These come before register parms, since they can require block-moves,
4041 which could clobber the registers used for register parms.
4042 Parms which have partial registers are not stored here,
4043 but we do preallocate space here if they want that. */
4045 for (i = 0; i < num_actuals; i++)
4047 /* Delay bounds until all other args are stored. */
4048 if (POINTER_BOUNDS_P (args[i].tree_value))
4049 continue;
4050 else if (args[i].reg == 0 || args[i].pass_on_stack)
4052 rtx_insn *before_arg = get_last_insn ();
4054 /* We don't allow passing huge (> 2^30 B) arguments
4055 by value. It would cause an overflow later on. */
4056 if (constant_lower_bound (adjusted_args_size.constant)
4057 >= (1 << (HOST_BITS_PER_INT - 2)))
4059 sorry ("passing too large argument on stack");
4060 continue;
4063 if (store_one_arg (&args[i], argblock, flags,
4064 adjusted_args_size.var != 0,
4065 reg_parm_stack_space)
4066 || (pass == 0
4067 && check_sibcall_argument_overlap (before_arg,
4068 &args[i], 1)))
4069 sibcall_failure = 1;
4072 if (args[i].stack)
4073 call_fusage
4074 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
4075 gen_rtx_USE (VOIDmode, args[i].stack),
4076 call_fusage);
4079 /* If we have a parm that is passed in registers but not in memory
4080 and whose alignment does not permit a direct copy into registers,
4081 make a group of pseudos that correspond to each register that we
4082 will later fill. */
4083 if (STRICT_ALIGNMENT)
4084 store_unaligned_arguments_into_pseudos (args, num_actuals);
4086 /* Now store any partially-in-registers parm.
4087 This is the last place a block-move can happen. */
4088 if (reg_parm_seen)
4089 for (i = 0; i < num_actuals; i++)
4090 if (args[i].partial != 0 && ! args[i].pass_on_stack)
4092 rtx_insn *before_arg = get_last_insn ();
4094 /* On targets with weird calling conventions (e.g. PA) it's
4095 hard to ensure that all cases of argument overlap between
4096 stack and registers work. Play it safe and bail out. */
4097 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
4099 sibcall_failure = 1;
4100 break;
4103 if (store_one_arg (&args[i], argblock, flags,
4104 adjusted_args_size.var != 0,
4105 reg_parm_stack_space)
4106 || (pass == 0
4107 && check_sibcall_argument_overlap (before_arg,
4108 &args[i], 1)))
4109 sibcall_failure = 1;
4112 bool any_regs = false;
4113 for (i = 0; i < num_actuals; i++)
4114 if (args[i].reg != NULL_RTX)
4116 any_regs = true;
4117 targetm.calls.call_args (args[i].reg, funtype);
4119 if (!any_regs)
4120 targetm.calls.call_args (pc_rtx, funtype);
4122 /* Figure out the register where the value, if any, will come back. */
4123 valreg = 0;
4124 valbnd = 0;
4125 if (TYPE_MODE (rettype) != VOIDmode
4126 && ! structure_value_addr)
4128 if (pcc_struct_value)
4130 valreg = hard_function_value (build_pointer_type (rettype),
4131 fndecl, NULL, (pass == 0));
4132 if (CALL_WITH_BOUNDS_P (exp))
4133 valbnd = targetm.calls.
4134 chkp_function_value_bounds (build_pointer_type (rettype),
4135 fndecl, (pass == 0));
4137 else
4139 valreg = hard_function_value (rettype, fndecl, fntype,
4140 (pass == 0));
4141 if (CALL_WITH_BOUNDS_P (exp))
4142 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
4143 fndecl,
4144 (pass == 0));
4147 /* If VALREG is a PARALLEL whose first member has a zero
4148 offset, use that. This is for targets such as m68k that
4149 return the same value in multiple places. */
4150 if (GET_CODE (valreg) == PARALLEL)
4152 rtx elem = XVECEXP (valreg, 0, 0);
4153 rtx where = XEXP (elem, 0);
4154 rtx offset = XEXP (elem, 1);
4155 if (offset == const0_rtx
4156 && GET_MODE (where) == GET_MODE (valreg))
4157 valreg = where;
4161 /* Store all bounds not passed in registers. */
4162 for (i = 0; i < num_actuals; i++)
4164 if (POINTER_BOUNDS_P (args[i].tree_value)
4165 && !args[i].reg)
4166 store_bounds (&args[i],
4167 args[i].pointer_arg == -1
4168 ? NULL
4169 : &args[args[i].pointer_arg]);
4172 /* If register arguments require space on the stack and stack space
4173 was not preallocated, allocate stack space here for arguments
4174 passed in registers. */
4175 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
4176 && !ACCUMULATE_OUTGOING_ARGS
4177 && must_preallocate == 0 && reg_parm_stack_space > 0)
4178 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
4180 /* Pass the function the address in which to return a
4181 structure value. */
4182 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
4184 structure_value_addr
4185 = convert_memory_address (Pmode, structure_value_addr);
4186 emit_move_insn (struct_value,
4187 force_reg (Pmode,
4188 force_operand (structure_value_addr,
4189 NULL_RTX)));
4191 if (REG_P (struct_value))
4192 use_reg (&call_fusage, struct_value);
4195 after_args = get_last_insn ();
4196 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
4197 static_chain_value, &call_fusage,
4198 reg_parm_seen, flags);
4200 load_register_parameters (args, num_actuals, &call_fusage, flags,
4201 pass == 0, &sibcall_failure);
4203 /* Save a pointer to the last insn before the call, so that we can
4204 later safely search backwards to find the CALL_INSN. */
4205 before_call = get_last_insn ();
4207 /* Set up next argument register. For sibling calls on machines
4208 with register windows this should be the incoming register. */
4209 if (pass == 0)
4210 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
4211 VOIDmode,
4212 void_type_node,
4213 true);
4214 else
4215 next_arg_reg = targetm.calls.function_arg (args_so_far,
4216 VOIDmode, void_type_node,
4217 true);
4219 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
4221 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
4222 arg_nr = num_actuals - arg_nr - 1;
4223 if (arg_nr >= 0
4224 && arg_nr < num_actuals
4225 && args[arg_nr].reg
4226 && valreg
4227 && REG_P (valreg)
4228 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
4229 call_fusage
4230 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
4231 gen_rtx_SET (valreg, args[arg_nr].reg),
4232 call_fusage);
4234 /* All arguments and registers used for the call must be set up by
4235 now! */
4237 /* Stack must be properly aligned now. */
4238 gcc_assert (!pass
4239 || multiple_p (stack_pointer_delta,
4240 preferred_unit_stack_boundary));
4242 /* Generate the actual call instruction. */
4243 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
4244 adjusted_args_size.constant, struct_value_size,
4245 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
4246 flags, args_so_far);
4248 if (flag_ipa_ra)
4250 rtx_call_insn *last;
4251 rtx datum = NULL_RTX;
4252 if (fndecl != NULL_TREE)
4254 datum = XEXP (DECL_RTL (fndecl), 0);
4255 gcc_assert (datum != NULL_RTX
4256 && GET_CODE (datum) == SYMBOL_REF);
4258 last = last_call_insn ();
4259 add_reg_note (last, REG_CALL_DECL, datum);
4262 /* If the call setup or the call itself overlaps with anything
4263 of the argument setup we probably clobbered our call address.
4264 In that case we can't do sibcalls. */
4265 if (pass == 0
4266 && check_sibcall_argument_overlap (after_args, 0, 0))
4267 sibcall_failure = 1;
4269 /* If a non-BLKmode value is returned at the most significant end
4270 of a register, shift the register right by the appropriate amount
4271 and update VALREG accordingly. BLKmode values are handled by the
4272 group load/store machinery below. */
4273 if (!structure_value_addr
4274 && !pcc_struct_value
4275 && TYPE_MODE (rettype) != VOIDmode
4276 && TYPE_MODE (rettype) != BLKmode
4277 && REG_P (valreg)
4278 && targetm.calls.return_in_msb (rettype))
4280 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
4281 sibcall_failure = 1;
4282 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
4285 if (pass && (flags & ECF_MALLOC))
4287 rtx temp = gen_reg_rtx (GET_MODE (valreg));
4288 rtx_insn *last, *insns;
4290 /* The return value from a malloc-like function is a pointer. */
4291 if (TREE_CODE (rettype) == POINTER_TYPE)
4292 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
4294 emit_move_insn (temp, valreg);
4296 /* The return value from a malloc-like function can not alias
4297 anything else. */
4298 last = get_last_insn ();
4299 add_reg_note (last, REG_NOALIAS, temp);
4301 /* Write out the sequence. */
4302 insns = get_insns ();
4303 end_sequence ();
4304 emit_insn (insns);
4305 valreg = temp;
4308 /* For calls to `setjmp', etc., inform
4309 function.c:setjmp_warnings that it should complain if
4310 nonvolatile values are live. For functions that cannot
4311 return, inform flow that control does not fall through. */
4313 if ((flags & ECF_NORETURN) || pass == 0)
4315 /* The barrier must be emitted
4316 immediately after the CALL_INSN. Some ports emit more
4317 than just a CALL_INSN above, so we must search for it here. */
4319 rtx_insn *last = get_last_insn ();
4320 while (!CALL_P (last))
4322 last = PREV_INSN (last);
4323 /* There was no CALL_INSN? */
4324 gcc_assert (last != before_call);
4327 emit_barrier_after (last);
4329 /* Stack adjustments after a noreturn call are dead code.
4330 However when NO_DEFER_POP is in effect, we must preserve
4331 stack_pointer_delta. */
4332 if (inhibit_defer_pop == 0)
4334 stack_pointer_delta = old_stack_allocated;
4335 pending_stack_adjust = 0;
4339 /* If value type not void, return an rtx for the value. */
4341 if (TYPE_MODE (rettype) == VOIDmode
4342 || ignore)
4343 target = const0_rtx;
4344 else if (structure_value_addr)
4346 if (target == 0 || !MEM_P (target))
4348 target
4349 = gen_rtx_MEM (TYPE_MODE (rettype),
4350 memory_address (TYPE_MODE (rettype),
4351 structure_value_addr));
4352 set_mem_attributes (target, rettype, 1);
4355 else if (pcc_struct_value)
4357 /* This is the special C++ case where we need to
4358 know what the true target was. We take care to
4359 never use this value more than once in one expression. */
4360 target = gen_rtx_MEM (TYPE_MODE (rettype),
4361 copy_to_reg (valreg));
4362 set_mem_attributes (target, rettype, 1);
4364 /* Handle calls that return values in multiple non-contiguous locations.
4365 The Irix 6 ABI has examples of this. */
4366 else if (GET_CODE (valreg) == PARALLEL)
4368 if (target == 0)
4369 target = emit_group_move_into_temps (valreg);
4370 else if (rtx_equal_p (target, valreg))
4372 else if (GET_CODE (target) == PARALLEL)
4373 /* Handle the result of a emit_group_move_into_temps
4374 call in the previous pass. */
4375 emit_group_move (target, valreg);
4376 else
4377 emit_group_store (target, valreg, rettype,
4378 int_size_in_bytes (rettype));
4380 else if (target
4381 && GET_MODE (target) == TYPE_MODE (rettype)
4382 && GET_MODE (target) == GET_MODE (valreg))
4384 bool may_overlap = false;
4386 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4387 reg to a plain register. */
4388 if (!REG_P (target) || HARD_REGISTER_P (target))
4389 valreg = avoid_likely_spilled_reg (valreg);
4391 /* If TARGET is a MEM in the argument area, and we have
4392 saved part of the argument area, then we can't store
4393 directly into TARGET as it may get overwritten when we
4394 restore the argument save area below. Don't work too
4395 hard though and simply force TARGET to a register if it
4396 is a MEM; the optimizer is quite likely to sort it out. */
4397 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4398 for (i = 0; i < num_actuals; i++)
4399 if (args[i].save_area)
4401 may_overlap = true;
4402 break;
4405 if (may_overlap)
4406 target = copy_to_reg (valreg);
4407 else
4409 /* TARGET and VALREG cannot be equal at this point
4410 because the latter would not have
4411 REG_FUNCTION_VALUE_P true, while the former would if
4412 it were referring to the same register.
4414 If they refer to the same register, this move will be
4415 a no-op, except when function inlining is being
4416 done. */
4417 emit_move_insn (target, valreg);
4419 /* If we are setting a MEM, this code must be executed.
4420 Since it is emitted after the call insn, sibcall
4421 optimization cannot be performed in that case. */
4422 if (MEM_P (target))
4423 sibcall_failure = 1;
4426 else
4427 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4429 /* If we promoted this return value, make the proper SUBREG.
4430 TARGET might be const0_rtx here, so be careful. */
4431 if (REG_P (target)
4432 && TYPE_MODE (rettype) != BLKmode
4433 && GET_MODE (target) != TYPE_MODE (rettype))
4435 tree type = rettype;
4436 int unsignedp = TYPE_UNSIGNED (type);
4437 machine_mode pmode;
4439 /* Ensure we promote as expected, and get the new unsignedness. */
4440 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4441 funtype, 1);
4442 gcc_assert (GET_MODE (target) == pmode);
4444 poly_uint64 offset = subreg_lowpart_offset (TYPE_MODE (type),
4445 GET_MODE (target));
4446 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4447 SUBREG_PROMOTED_VAR_P (target) = 1;
4448 SUBREG_PROMOTED_SET (target, unsignedp);
4451 /* If size of args is variable or this was a constructor call for a stack
4452 argument, restore saved stack-pointer value. */
4454 if (old_stack_level)
4456 rtx_insn *prev = get_last_insn ();
4458 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4459 stack_pointer_delta = old_stack_pointer_delta;
4461 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4463 pending_stack_adjust = old_pending_adj;
4464 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4465 stack_arg_under_construction = old_stack_arg_under_construction;
4466 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4467 stack_usage_map = initial_stack_usage_map;
4468 stack_usage_watermark = initial_stack_usage_watermark;
4469 sibcall_failure = 1;
4471 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4473 #ifdef REG_PARM_STACK_SPACE
4474 if (save_area)
4475 restore_fixed_argument_area (save_area, argblock,
4476 high_to_save, low_to_save);
4477 #endif
4479 /* If we saved any argument areas, restore them. */
4480 for (i = 0; i < num_actuals; i++)
4481 if (args[i].save_area)
4483 machine_mode save_mode = GET_MODE (args[i].save_area);
4484 rtx stack_area
4485 = gen_rtx_MEM (save_mode,
4486 memory_address (save_mode,
4487 XEXP (args[i].stack_slot, 0)));
4489 if (save_mode != BLKmode)
4490 emit_move_insn (stack_area, args[i].save_area);
4491 else
4492 emit_block_move (stack_area, args[i].save_area,
4493 (gen_int_mode
4494 (args[i].locate.size.constant, Pmode)),
4495 BLOCK_OP_CALL_PARM);
4498 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4499 stack_usage_map = initial_stack_usage_map;
4500 stack_usage_watermark = initial_stack_usage_watermark;
4503 /* If this was alloca, record the new stack level. */
4504 if (flags & ECF_MAY_BE_ALLOCA)
4505 record_new_stack_level ();
4507 /* Free up storage we no longer need. */
4508 for (i = 0; i < num_actuals; ++i)
4509 free (args[i].aligned_regs);
4511 targetm.calls.end_call_args ();
4513 insns = get_insns ();
4514 end_sequence ();
4516 if (pass == 0)
4518 tail_call_insns = insns;
4520 /* Restore the pending stack adjustment now that we have
4521 finished generating the sibling call sequence. */
4523 restore_pending_stack_adjust (&save);
4525 /* Prepare arg structure for next iteration. */
4526 for (i = 0; i < num_actuals; i++)
4528 args[i].value = 0;
4529 args[i].aligned_regs = 0;
4530 args[i].stack = 0;
4533 sbitmap_free (stored_args_map);
4534 internal_arg_pointer_exp_state.scan_start = NULL;
4535 internal_arg_pointer_exp_state.cache.release ();
4537 else
4539 normal_call_insns = insns;
4541 /* Verify that we've deallocated all the stack we used. */
4542 gcc_assert ((flags & ECF_NORETURN)
4543 || known_eq (old_stack_allocated,
4544 stack_pointer_delta
4545 - pending_stack_adjust));
4548 /* If something prevents making this a sibling call,
4549 zero out the sequence. */
4550 if (sibcall_failure)
4551 tail_call_insns = NULL;
4552 else
4553 break;
4556 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4557 arguments too, as argument area is now clobbered by the call. */
4558 if (tail_call_insns)
4560 emit_insn (tail_call_insns);
4561 crtl->tail_call_emit = true;
4563 else
4565 emit_insn (normal_call_insns);
4566 if (try_tail_call)
4567 /* Ideally we'd emit a message for all of the ways that it could
4568 have failed. */
4569 maybe_complain_about_tail_call (exp, "tail call production failed");
4572 currently_expanding_call--;
4574 free (stack_usage_map_buf);
4575 free (args);
4577 /* Join result with returned bounds so caller may use them if needed. */
4578 target = chkp_join_splitted_slot (target, valbnd);
4580 return target;
4583 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4584 this function's incoming arguments.
4586 At the start of RTL generation we know the only REG_EQUIV notes
4587 in the rtl chain are those for incoming arguments, so we can look
4588 for REG_EQUIV notes between the start of the function and the
4589 NOTE_INSN_FUNCTION_BEG.
4591 This is (slight) overkill. We could keep track of the highest
4592 argument we clobber and be more selective in removing notes, but it
4593 does not seem to be worth the effort. */
4595 void
4596 fixup_tail_calls (void)
4598 rtx_insn *insn;
4600 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4602 rtx note;
4604 /* There are never REG_EQUIV notes for the incoming arguments
4605 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4606 if (NOTE_P (insn)
4607 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4608 break;
4610 note = find_reg_note (insn, REG_EQUIV, 0);
4611 if (note)
4612 remove_note (insn, note);
4613 note = find_reg_note (insn, REG_EQUIV, 0);
4614 gcc_assert (!note);
4618 /* Traverse a list of TYPES and expand all complex types into their
4619 components. */
4620 static tree
4621 split_complex_types (tree types)
4623 tree p;
4625 /* Before allocating memory, check for the common case of no complex. */
4626 for (p = types; p; p = TREE_CHAIN (p))
4628 tree type = TREE_VALUE (p);
4629 if (TREE_CODE (type) == COMPLEX_TYPE
4630 && targetm.calls.split_complex_arg (type))
4631 goto found;
4633 return types;
4635 found:
4636 types = copy_list (types);
4638 for (p = types; p; p = TREE_CHAIN (p))
4640 tree complex_type = TREE_VALUE (p);
4642 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4643 && targetm.calls.split_complex_arg (complex_type))
4645 tree next, imag;
4647 /* Rewrite complex type with component type. */
4648 TREE_VALUE (p) = TREE_TYPE (complex_type);
4649 next = TREE_CHAIN (p);
4651 /* Add another component type for the imaginary part. */
4652 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4653 TREE_CHAIN (p) = imag;
4654 TREE_CHAIN (imag) = next;
4656 /* Skip the newly created node. */
4657 p = TREE_CHAIN (p);
4661 return types;
4664 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4665 for a value of mode OUTMODE,
4666 with NARGS different arguments, passed as ARGS.
4667 Store the return value if RETVAL is nonzero: store it in VALUE if
4668 VALUE is nonnull, otherwise pick a convenient location. In either
4669 case return the location of the stored value.
4671 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4672 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4673 other types of library calls. */
4676 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4677 enum libcall_type fn_type,
4678 machine_mode outmode, int nargs, rtx_mode_t *args)
4680 /* Total size in bytes of all the stack-parms scanned so far. */
4681 struct args_size args_size;
4682 /* Size of arguments before any adjustments (such as rounding). */
4683 struct args_size original_args_size;
4684 int argnum;
4685 rtx fun;
4686 /* Todo, choose the correct decl type of orgfun. Sadly this information
4687 isn't present here, so we default to native calling abi here. */
4688 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4689 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4690 int count;
4691 rtx argblock = 0;
4692 CUMULATIVE_ARGS args_so_far_v;
4693 cumulative_args_t args_so_far;
4694 struct arg
4696 rtx value;
4697 machine_mode mode;
4698 rtx reg;
4699 int partial;
4700 struct locate_and_pad_arg_data locate;
4701 rtx save_area;
4703 struct arg *argvec;
4704 int old_inhibit_defer_pop = inhibit_defer_pop;
4705 rtx call_fusage = 0;
4706 rtx mem_value = 0;
4707 rtx valreg;
4708 int pcc_struct_value = 0;
4709 poly_int64 struct_value_size = 0;
4710 int flags;
4711 int reg_parm_stack_space = 0;
4712 poly_int64 needed;
4713 rtx_insn *before_call;
4714 bool have_push_fusage;
4715 tree tfom; /* type_for_mode (outmode, 0) */
4717 #ifdef REG_PARM_STACK_SPACE
4718 /* Define the boundary of the register parm stack space that needs to be
4719 save, if any. */
4720 int low_to_save = 0, high_to_save = 0;
4721 rtx save_area = 0; /* Place that it is saved. */
4722 #endif
4724 /* Size of the stack reserved for parameter registers. */
4725 unsigned int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4726 char *initial_stack_usage_map = stack_usage_map;
4727 unsigned HOST_WIDE_INT initial_stack_usage_watermark = stack_usage_watermark;
4728 char *stack_usage_map_buf = NULL;
4730 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4732 #ifdef REG_PARM_STACK_SPACE
4733 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4734 #endif
4736 /* By default, library functions cannot throw. */
4737 flags = ECF_NOTHROW;
4739 switch (fn_type)
4741 case LCT_NORMAL:
4742 break;
4743 case LCT_CONST:
4744 flags |= ECF_CONST;
4745 break;
4746 case LCT_PURE:
4747 flags |= ECF_PURE;
4748 break;
4749 case LCT_NORETURN:
4750 flags |= ECF_NORETURN;
4751 break;
4752 case LCT_THROW:
4753 flags &= ~ECF_NOTHROW;
4754 break;
4755 case LCT_RETURNS_TWICE:
4756 flags = ECF_RETURNS_TWICE;
4757 break;
4759 fun = orgfun;
4761 /* Ensure current function's preferred stack boundary is at least
4762 what we need. */
4763 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4764 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4766 /* If this kind of value comes back in memory,
4767 decide where in memory it should come back. */
4768 if (outmode != VOIDmode)
4770 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4771 if (aggregate_value_p (tfom, 0))
4773 #ifdef PCC_STATIC_STRUCT_RETURN
4774 rtx pointer_reg
4775 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4776 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4777 pcc_struct_value = 1;
4778 if (value == 0)
4779 value = gen_reg_rtx (outmode);
4780 #else /* not PCC_STATIC_STRUCT_RETURN */
4781 struct_value_size = GET_MODE_SIZE (outmode);
4782 if (value != 0 && MEM_P (value))
4783 mem_value = value;
4784 else
4785 mem_value = assign_temp (tfom, 1, 1);
4786 #endif
4787 /* This call returns a big structure. */
4788 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4791 else
4792 tfom = void_type_node;
4794 /* ??? Unfinished: must pass the memory address as an argument. */
4796 /* Copy all the libcall-arguments out of the varargs data
4797 and into a vector ARGVEC.
4799 Compute how to pass each argument. We only support a very small subset
4800 of the full argument passing conventions to limit complexity here since
4801 library functions shouldn't have many args. */
4803 argvec = XALLOCAVEC (struct arg, nargs + 1);
4804 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4806 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4807 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4808 #else
4809 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4810 #endif
4811 args_so_far = pack_cumulative_args (&args_so_far_v);
4813 args_size.constant = 0;
4814 args_size.var = 0;
4816 count = 0;
4818 push_temp_slots ();
4820 /* If there's a structure value address to be passed,
4821 either pass it in the special place, or pass it as an extra argument. */
4822 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4824 rtx addr = XEXP (mem_value, 0);
4826 nargs++;
4828 /* Make sure it is a reasonable operand for a move or push insn. */
4829 if (!REG_P (addr) && !MEM_P (addr)
4830 && !(CONSTANT_P (addr)
4831 && targetm.legitimate_constant_p (Pmode, addr)))
4832 addr = force_operand (addr, NULL_RTX);
4834 argvec[count].value = addr;
4835 argvec[count].mode = Pmode;
4836 argvec[count].partial = 0;
4838 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4839 Pmode, NULL_TREE, true);
4840 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4841 NULL_TREE, 1) == 0);
4843 locate_and_pad_parm (Pmode, NULL_TREE,
4844 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4846 #else
4847 argvec[count].reg != 0,
4848 #endif
4849 reg_parm_stack_space, 0,
4850 NULL_TREE, &args_size, &argvec[count].locate);
4852 if (argvec[count].reg == 0 || argvec[count].partial != 0
4853 || reg_parm_stack_space > 0)
4854 args_size.constant += argvec[count].locate.size.constant;
4856 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4858 count++;
4861 for (unsigned int i = 0; count < nargs; i++, count++)
4863 rtx val = args[i].first;
4864 machine_mode mode = args[i].second;
4865 int unsigned_p = 0;
4867 /* We cannot convert the arg value to the mode the library wants here;
4868 must do it earlier where we know the signedness of the arg. */
4869 gcc_assert (mode != BLKmode
4870 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4872 /* Make sure it is a reasonable operand for a move or push insn. */
4873 if (!REG_P (val) && !MEM_P (val)
4874 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4875 val = force_operand (val, NULL_RTX);
4877 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4879 rtx slot;
4880 int must_copy
4881 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4883 /* If this was a CONST function, it is now PURE since it now
4884 reads memory. */
4885 if (flags & ECF_CONST)
4887 flags &= ~ECF_CONST;
4888 flags |= ECF_PURE;
4891 if (MEM_P (val) && !must_copy)
4893 tree val_expr = MEM_EXPR (val);
4894 if (val_expr)
4895 mark_addressable (val_expr);
4896 slot = val;
4898 else
4900 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4901 1, 1);
4902 emit_move_insn (slot, val);
4905 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4906 gen_rtx_USE (VOIDmode, slot),
4907 call_fusage);
4908 if (must_copy)
4909 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4910 gen_rtx_CLOBBER (VOIDmode,
4911 slot),
4912 call_fusage);
4914 mode = Pmode;
4915 val = force_operand (XEXP (slot, 0), NULL_RTX);
4918 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4919 argvec[count].mode = mode;
4920 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4921 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4922 NULL_TREE, true);
4924 argvec[count].partial
4925 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4927 if (argvec[count].reg == 0
4928 || argvec[count].partial != 0
4929 || reg_parm_stack_space > 0)
4931 locate_and_pad_parm (mode, NULL_TREE,
4932 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4934 #else
4935 argvec[count].reg != 0,
4936 #endif
4937 reg_parm_stack_space, argvec[count].partial,
4938 NULL_TREE, &args_size, &argvec[count].locate);
4939 args_size.constant += argvec[count].locate.size.constant;
4940 gcc_assert (!argvec[count].locate.size.var);
4942 #ifdef BLOCK_REG_PADDING
4943 else
4944 /* The argument is passed entirely in registers. See at which
4945 end it should be padded. */
4946 argvec[count].locate.where_pad =
4947 BLOCK_REG_PADDING (mode, NULL_TREE,
4948 known_le (GET_MODE_SIZE (mode), UNITS_PER_WORD));
4949 #endif
4951 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4954 /* If this machine requires an external definition for library
4955 functions, write one out. */
4956 assemble_external_libcall (fun);
4958 original_args_size = args_size;
4959 args_size.constant = (aligned_upper_bound (args_size.constant
4960 + stack_pointer_delta,
4961 STACK_BYTES)
4962 - stack_pointer_delta);
4964 args_size.constant = upper_bound (args_size.constant,
4965 reg_parm_stack_space);
4967 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4968 args_size.constant -= reg_parm_stack_space;
4970 crtl->outgoing_args_size = upper_bound (crtl->outgoing_args_size,
4971 args_size.constant);
4973 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4975 poly_int64 pushed = args_size.constant + pending_stack_adjust;
4976 current_function_pushed_stack_size
4977 = upper_bound (current_function_pushed_stack_size, pushed);
4980 if (ACCUMULATE_OUTGOING_ARGS)
4982 /* Since the stack pointer will never be pushed, it is possible for
4983 the evaluation of a parm to clobber something we have already
4984 written to the stack. Since most function calls on RISC machines
4985 do not use the stack, this is uncommon, but must work correctly.
4987 Therefore, we save any area of the stack that was already written
4988 and that we are using. Here we set up to do this by making a new
4989 stack usage map from the old one.
4991 Another approach might be to try to reorder the argument
4992 evaluations to avoid this conflicting stack usage. */
4994 needed = args_size.constant;
4996 /* Since we will be writing into the entire argument area, the
4997 map must be allocated for its entire size, not just the part that
4998 is the responsibility of the caller. */
4999 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
5000 needed += reg_parm_stack_space;
5002 poly_int64 limit = needed;
5003 if (ARGS_GROW_DOWNWARD)
5004 limit += 1;
5006 /* For polynomial sizes, this is the maximum possible size needed
5007 for arguments with a constant size and offset. */
5008 HOST_WIDE_INT const_limit = constant_lower_bound (limit);
5009 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
5010 const_limit);
5012 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
5013 stack_usage_map = stack_usage_map_buf;
5015 if (initial_highest_arg_in_use)
5016 memcpy (stack_usage_map, initial_stack_usage_map,
5017 initial_highest_arg_in_use);
5019 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
5020 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
5021 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
5022 needed = 0;
5024 /* We must be careful to use virtual regs before they're instantiated,
5025 and real regs afterwards. Loop optimization, for example, can create
5026 new libcalls after we've instantiated the virtual regs, and if we
5027 use virtuals anyway, they won't match the rtl patterns. */
5029 if (virtuals_instantiated)
5030 argblock = plus_constant (Pmode, stack_pointer_rtx,
5031 STACK_POINTER_OFFSET);
5032 else
5033 argblock = virtual_outgoing_args_rtx;
5035 else
5037 if (!PUSH_ARGS)
5038 argblock = push_block (gen_int_mode (args_size.constant, Pmode), 0, 0);
5041 /* We push args individually in reverse order, perform stack alignment
5042 before the first push (the last arg). */
5043 if (argblock == 0)
5044 anti_adjust_stack (gen_int_mode (args_size.constant
5045 - original_args_size.constant,
5046 Pmode));
5048 argnum = nargs - 1;
5050 #ifdef REG_PARM_STACK_SPACE
5051 if (ACCUMULATE_OUTGOING_ARGS)
5053 /* The argument list is the property of the called routine and it
5054 may clobber it. If the fixed area has been used for previous
5055 parameters, we must save and restore it. */
5056 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
5057 &low_to_save, &high_to_save);
5059 #endif
5061 /* When expanding a normal call, args are stored in push order,
5062 which is the reverse of what we have here. */
5063 bool any_regs = false;
5064 for (int i = nargs; i-- > 0; )
5065 if (argvec[i].reg != NULL_RTX)
5067 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
5068 any_regs = true;
5070 if (!any_regs)
5071 targetm.calls.call_args (pc_rtx, NULL_TREE);
5073 /* Push the args that need to be pushed. */
5075 have_push_fusage = false;
5077 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5078 are to be pushed. */
5079 for (count = 0; count < nargs; count++, argnum--)
5081 machine_mode mode = argvec[argnum].mode;
5082 rtx val = argvec[argnum].value;
5083 rtx reg = argvec[argnum].reg;
5084 int partial = argvec[argnum].partial;
5085 unsigned int parm_align = argvec[argnum].locate.boundary;
5086 poly_int64 lower_bound = 0, upper_bound = 0;
5088 if (! (reg != 0 && partial == 0))
5090 rtx use;
5092 if (ACCUMULATE_OUTGOING_ARGS)
5094 /* If this is being stored into a pre-allocated, fixed-size,
5095 stack area, save any previous data at that location. */
5097 if (ARGS_GROW_DOWNWARD)
5099 /* stack_slot is negative, but we want to index stack_usage_map
5100 with positive values. */
5101 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
5102 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
5104 else
5106 lower_bound = argvec[argnum].locate.slot_offset.constant;
5107 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
5110 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5111 reg_parm_stack_space))
5113 /* We need to make a save area. */
5114 poly_uint64 size
5115 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
5116 machine_mode save_mode
5117 = int_mode_for_size (size, 1).else_blk ();
5118 rtx adr
5119 = plus_constant (Pmode, argblock,
5120 argvec[argnum].locate.offset.constant);
5121 rtx stack_area
5122 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
5124 if (save_mode == BLKmode)
5126 argvec[argnum].save_area
5127 = assign_stack_temp (BLKmode,
5128 argvec[argnum].locate.size.constant
5131 emit_block_move (validize_mem
5132 (copy_rtx (argvec[argnum].save_area)),
5133 stack_area,
5134 (gen_int_mode
5135 (argvec[argnum].locate.size.constant,
5136 Pmode)),
5137 BLOCK_OP_CALL_PARM);
5139 else
5141 argvec[argnum].save_area = gen_reg_rtx (save_mode);
5143 emit_move_insn (argvec[argnum].save_area, stack_area);
5148 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
5149 partial, reg, 0, argblock,
5150 (gen_int_mode
5151 (argvec[argnum].locate.offset.constant, Pmode)),
5152 reg_parm_stack_space,
5153 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
5155 /* Now mark the segment we just used. */
5156 if (ACCUMULATE_OUTGOING_ARGS)
5157 mark_stack_region_used (lower_bound, upper_bound);
5159 NO_DEFER_POP;
5161 /* Indicate argument access so that alias.c knows that these
5162 values are live. */
5163 if (argblock)
5164 use = plus_constant (Pmode, argblock,
5165 argvec[argnum].locate.offset.constant);
5166 else if (have_push_fusage)
5167 continue;
5168 else
5170 /* When arguments are pushed, trying to tell alias.c where
5171 exactly this argument is won't work, because the
5172 auto-increment causes confusion. So we merely indicate
5173 that we access something with a known mode somewhere on
5174 the stack. */
5175 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
5176 gen_rtx_SCRATCH (Pmode));
5177 have_push_fusage = true;
5179 use = gen_rtx_MEM (argvec[argnum].mode, use);
5180 use = gen_rtx_USE (VOIDmode, use);
5181 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
5185 argnum = nargs - 1;
5187 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
5189 /* Now load any reg parms into their regs. */
5191 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
5192 are to be pushed. */
5193 for (count = 0; count < nargs; count++, argnum--)
5195 machine_mode mode = argvec[argnum].mode;
5196 rtx val = argvec[argnum].value;
5197 rtx reg = argvec[argnum].reg;
5198 int partial = argvec[argnum].partial;
5200 /* Handle calls that pass values in multiple non-contiguous
5201 locations. The PA64 has examples of this for library calls. */
5202 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5203 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
5204 else if (reg != 0 && partial == 0)
5206 emit_move_insn (reg, val);
5207 #ifdef BLOCK_REG_PADDING
5208 poly_int64 size = GET_MODE_SIZE (argvec[argnum].mode);
5210 /* Copied from load_register_parameters. */
5212 /* Handle case where we have a value that needs shifting
5213 up to the msb. eg. a QImode value and we're padding
5214 upward on a BYTES_BIG_ENDIAN machine. */
5215 if (known_lt (size, UNITS_PER_WORD)
5216 && (argvec[argnum].locate.where_pad
5217 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5219 rtx x;
5220 poly_int64 shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
5222 /* Assigning REG here rather than a temp makes CALL_FUSAGE
5223 report the whole reg as used. Strictly speaking, the
5224 call only uses SIZE bytes at the msb end, but it doesn't
5225 seem worth generating rtl to say that. */
5226 reg = gen_rtx_REG (word_mode, REGNO (reg));
5227 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
5228 if (x != reg)
5229 emit_move_insn (reg, x);
5231 #endif
5234 NO_DEFER_POP;
5237 /* Any regs containing parms remain in use through the call. */
5238 for (count = 0; count < nargs; count++)
5240 rtx reg = argvec[count].reg;
5241 if (reg != 0 && GET_CODE (reg) == PARALLEL)
5242 use_group_regs (&call_fusage, reg);
5243 else if (reg != 0)
5245 int partial = argvec[count].partial;
5246 if (partial)
5248 int nregs;
5249 gcc_assert (partial % UNITS_PER_WORD == 0);
5250 nregs = partial / UNITS_PER_WORD;
5251 use_regs (&call_fusage, REGNO (reg), nregs);
5253 else
5254 use_reg (&call_fusage, reg);
5258 /* Pass the function the address in which to return a structure value. */
5259 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
5261 emit_move_insn (struct_value,
5262 force_reg (Pmode,
5263 force_operand (XEXP (mem_value, 0),
5264 NULL_RTX)));
5265 if (REG_P (struct_value))
5266 use_reg (&call_fusage, struct_value);
5269 /* Don't allow popping to be deferred, since then
5270 cse'ing of library calls could delete a call and leave the pop. */
5271 NO_DEFER_POP;
5272 valreg = (mem_value == 0 && outmode != VOIDmode
5273 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
5275 /* Stack must be properly aligned now. */
5276 gcc_assert (multiple_p (stack_pointer_delta,
5277 PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT));
5279 before_call = get_last_insn ();
5281 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
5282 will set inhibit_defer_pop to that value. */
5283 /* The return type is needed to decide how many bytes the function pops.
5284 Signedness plays no role in that, so for simplicity, we pretend it's
5285 always signed. We also assume that the list of arguments passed has
5286 no impact, so we pretend it is unknown. */
5288 emit_call_1 (fun, NULL,
5289 get_identifier (XSTR (orgfun, 0)),
5290 build_function_type (tfom, NULL_TREE),
5291 original_args_size.constant, args_size.constant,
5292 struct_value_size,
5293 targetm.calls.function_arg (args_so_far,
5294 VOIDmode, void_type_node, true),
5295 valreg,
5296 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
5298 if (flag_ipa_ra)
5300 rtx datum = orgfun;
5301 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
5302 rtx_call_insn *last = last_call_insn ();
5303 add_reg_note (last, REG_CALL_DECL, datum);
5306 /* Right-shift returned value if necessary. */
5307 if (!pcc_struct_value
5308 && TYPE_MODE (tfom) != BLKmode
5309 && targetm.calls.return_in_msb (tfom))
5311 shift_return_value (TYPE_MODE (tfom), false, valreg);
5312 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5315 targetm.calls.end_call_args ();
5317 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5318 that it should complain if nonvolatile values are live. For
5319 functions that cannot return, inform flow that control does not
5320 fall through. */
5321 if (flags & ECF_NORETURN)
5323 /* The barrier note must be emitted
5324 immediately after the CALL_INSN. Some ports emit more than
5325 just a CALL_INSN above, so we must search for it here. */
5326 rtx_insn *last = get_last_insn ();
5327 while (!CALL_P (last))
5329 last = PREV_INSN (last);
5330 /* There was no CALL_INSN? */
5331 gcc_assert (last != before_call);
5334 emit_barrier_after (last);
5337 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5338 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5339 if (flags & ECF_NOTHROW)
5341 rtx_insn *last = get_last_insn ();
5342 while (!CALL_P (last))
5344 last = PREV_INSN (last);
5345 /* There was no CALL_INSN? */
5346 gcc_assert (last != before_call);
5349 make_reg_eh_region_note_nothrow_nononlocal (last);
5352 /* Now restore inhibit_defer_pop to its actual original value. */
5353 OK_DEFER_POP;
5355 pop_temp_slots ();
5357 /* Copy the value to the right place. */
5358 if (outmode != VOIDmode && retval)
5360 if (mem_value)
5362 if (value == 0)
5363 value = mem_value;
5364 if (value != mem_value)
5365 emit_move_insn (value, mem_value);
5367 else if (GET_CODE (valreg) == PARALLEL)
5369 if (value == 0)
5370 value = gen_reg_rtx (outmode);
5371 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5373 else
5375 /* Convert to the proper mode if a promotion has been active. */
5376 if (GET_MODE (valreg) != outmode)
5378 int unsignedp = TYPE_UNSIGNED (tfom);
5380 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5381 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5382 == GET_MODE (valreg));
5383 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5386 if (value != 0)
5387 emit_move_insn (value, valreg);
5388 else
5389 value = valreg;
5393 if (ACCUMULATE_OUTGOING_ARGS)
5395 #ifdef REG_PARM_STACK_SPACE
5396 if (save_area)
5397 restore_fixed_argument_area (save_area, argblock,
5398 high_to_save, low_to_save);
5399 #endif
5401 /* If we saved any argument areas, restore them. */
5402 for (count = 0; count < nargs; count++)
5403 if (argvec[count].save_area)
5405 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5406 rtx adr = plus_constant (Pmode, argblock,
5407 argvec[count].locate.offset.constant);
5408 rtx stack_area = gen_rtx_MEM (save_mode,
5409 memory_address (save_mode, adr));
5411 if (save_mode == BLKmode)
5412 emit_block_move (stack_area,
5413 validize_mem
5414 (copy_rtx (argvec[count].save_area)),
5415 (gen_int_mode
5416 (argvec[count].locate.size.constant, Pmode)),
5417 BLOCK_OP_CALL_PARM);
5418 else
5419 emit_move_insn (stack_area, argvec[count].save_area);
5422 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5423 stack_usage_map = initial_stack_usage_map;
5424 stack_usage_watermark = initial_stack_usage_watermark;
5427 free (stack_usage_map_buf);
5429 return value;
5434 /* Store pointer bounds argument ARG into Bounds Table entry
5435 associated with PARM. */
5436 static void
5437 store_bounds (struct arg_data *arg, struct arg_data *parm)
5439 rtx slot = NULL, ptr = NULL, addr = NULL;
5441 /* We may pass bounds not associated with any pointer. */
5442 if (!parm)
5444 gcc_assert (arg->special_slot);
5445 slot = arg->special_slot;
5446 ptr = const0_rtx;
5448 /* Find pointer associated with bounds and where it is
5449 passed. */
5450 else
5452 if (!parm->reg)
5454 gcc_assert (!arg->special_slot);
5456 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5458 else if (REG_P (parm->reg))
5460 gcc_assert (arg->special_slot);
5461 slot = arg->special_slot;
5463 if (MEM_P (parm->value))
5464 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5465 else if (REG_P (parm->value))
5466 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5467 else
5469 gcc_assert (!arg->pointer_offset);
5470 ptr = parm->value;
5473 else
5475 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5477 gcc_assert (arg->special_slot);
5478 slot = arg->special_slot;
5480 if (parm->parallel_value)
5481 ptr = chkp_get_value_with_offs (parm->parallel_value,
5482 GEN_INT (arg->pointer_offset));
5483 else
5484 gcc_unreachable ();
5488 /* Expand bounds. */
5489 if (!arg->value)
5490 arg->value = expand_normal (arg->tree_value);
5492 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5495 /* Store a single argument for a function call
5496 into the register or memory area where it must be passed.
5497 *ARG describes the argument value and where to pass it.
5499 ARGBLOCK is the address of the stack-block for all the arguments,
5500 or 0 on a machine where arguments are pushed individually.
5502 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5503 so must be careful about how the stack is used.
5505 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5506 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5507 that we need not worry about saving and restoring the stack.
5509 FNDECL is the declaration of the function we are calling.
5511 Return nonzero if this arg should cause sibcall failure,
5512 zero otherwise. */
5514 static int
5515 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5516 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5518 tree pval = arg->tree_value;
5519 rtx reg = 0;
5520 int partial = 0;
5521 poly_int64 used = 0;
5522 poly_int64 lower_bound = 0, upper_bound = 0;
5523 int sibcall_failure = 0;
5525 if (TREE_CODE (pval) == ERROR_MARK)
5526 return 1;
5528 /* Push a new temporary level for any temporaries we make for
5529 this argument. */
5530 push_temp_slots ();
5532 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5534 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5535 save any previous data at that location. */
5536 if (argblock && ! variable_size && arg->stack)
5538 if (ARGS_GROW_DOWNWARD)
5540 /* stack_slot is negative, but we want to index stack_usage_map
5541 with positive values. */
5542 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5544 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5545 upper_bound = -rtx_to_poly_int64 (offset) + 1;
5547 else
5548 upper_bound = 0;
5550 lower_bound = upper_bound - arg->locate.size.constant;
5552 else
5554 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5556 rtx offset = XEXP (XEXP (arg->stack_slot, 0), 1);
5557 lower_bound = rtx_to_poly_int64 (offset);
5559 else
5560 lower_bound = 0;
5562 upper_bound = lower_bound + arg->locate.size.constant;
5565 if (stack_region_maybe_used_p (lower_bound, upper_bound,
5566 reg_parm_stack_space))
5568 /* We need to make a save area. */
5569 poly_uint64 size = arg->locate.size.constant * BITS_PER_UNIT;
5570 machine_mode save_mode
5571 = int_mode_for_size (size, 1).else_blk ();
5572 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5573 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5575 if (save_mode == BLKmode)
5577 arg->save_area
5578 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5579 preserve_temp_slots (arg->save_area);
5580 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5581 stack_area,
5582 (gen_int_mode
5583 (arg->locate.size.constant, Pmode)),
5584 BLOCK_OP_CALL_PARM);
5586 else
5588 arg->save_area = gen_reg_rtx (save_mode);
5589 emit_move_insn (arg->save_area, stack_area);
5595 /* If this isn't going to be placed on both the stack and in registers,
5596 set up the register and number of words. */
5597 if (! arg->pass_on_stack)
5599 if (flags & ECF_SIBCALL)
5600 reg = arg->tail_call_reg;
5601 else
5602 reg = arg->reg;
5603 partial = arg->partial;
5606 /* Being passed entirely in a register. We shouldn't be called in
5607 this case. */
5608 gcc_assert (reg == 0 || partial != 0);
5610 /* If this arg needs special alignment, don't load the registers
5611 here. */
5612 if (arg->n_aligned_regs != 0)
5613 reg = 0;
5615 /* If this is being passed partially in a register, we can't evaluate
5616 it directly into its stack slot. Otherwise, we can. */
5617 if (arg->value == 0)
5619 /* stack_arg_under_construction is nonzero if a function argument is
5620 being evaluated directly into the outgoing argument list and
5621 expand_call must take special action to preserve the argument list
5622 if it is called recursively.
5624 For scalar function arguments stack_usage_map is sufficient to
5625 determine which stack slots must be saved and restored. Scalar
5626 arguments in general have pass_on_stack == 0.
5628 If this argument is initialized by a function which takes the
5629 address of the argument (a C++ constructor or a C function
5630 returning a BLKmode structure), then stack_usage_map is
5631 insufficient and expand_call must push the stack around the
5632 function call. Such arguments have pass_on_stack == 1.
5634 Note that it is always safe to set stack_arg_under_construction,
5635 but this generates suboptimal code if set when not needed. */
5637 if (arg->pass_on_stack)
5638 stack_arg_under_construction++;
5640 arg->value = expand_expr (pval,
5641 (partial
5642 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5643 ? NULL_RTX : arg->stack,
5644 VOIDmode, EXPAND_STACK_PARM);
5646 /* If we are promoting object (or for any other reason) the mode
5647 doesn't agree, convert the mode. */
5649 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5650 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5651 arg->value, arg->unsignedp);
5653 if (arg->pass_on_stack)
5654 stack_arg_under_construction--;
5657 /* Check for overlap with already clobbered argument area. */
5658 if ((flags & ECF_SIBCALL)
5659 && MEM_P (arg->value)
5660 && mem_might_overlap_already_clobbered_arg_p (XEXP (arg->value, 0),
5661 arg->locate.size.constant))
5662 sibcall_failure = 1;
5664 /* Don't allow anything left on stack from computation
5665 of argument to alloca. */
5666 if (flags & ECF_MAY_BE_ALLOCA)
5667 do_pending_stack_adjust ();
5669 if (arg->value == arg->stack)
5670 /* If the value is already in the stack slot, we are done. */
5672 else if (arg->mode != BLKmode)
5674 unsigned int parm_align;
5676 /* Argument is a scalar, not entirely passed in registers.
5677 (If part is passed in registers, arg->partial says how much
5678 and emit_push_insn will take care of putting it there.)
5680 Push it, and if its size is less than the
5681 amount of space allocated to it,
5682 also bump stack pointer by the additional space.
5683 Note that in C the default argument promotions
5684 will prevent such mismatches. */
5686 poly_int64 size = (TYPE_EMPTY_P (TREE_TYPE (pval))
5687 ? 0 : GET_MODE_SIZE (arg->mode));
5689 /* Compute how much space the push instruction will push.
5690 On many machines, pushing a byte will advance the stack
5691 pointer by a halfword. */
5692 #ifdef PUSH_ROUNDING
5693 size = PUSH_ROUNDING (size);
5694 #endif
5695 used = size;
5697 /* Compute how much space the argument should get:
5698 round up to a multiple of the alignment for arguments. */
5699 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5700 != PAD_NONE)
5701 /* At the moment we don't (need to) support ABIs for which the
5702 padding isn't known at compile time. In principle it should
5703 be easy to add though. */
5704 used = force_align_up (size, PARM_BOUNDARY / BITS_PER_UNIT);
5706 /* Compute the alignment of the pushed argument. */
5707 parm_align = arg->locate.boundary;
5708 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5709 == PAD_DOWNWARD)
5711 poly_int64 pad = used - size;
5712 unsigned int pad_align = known_alignment (pad) * BITS_PER_UNIT;
5713 if (pad_align != 0)
5714 parm_align = MIN (parm_align, pad_align);
5717 /* This isn't already where we want it on the stack, so put it there.
5718 This can either be done with push or copy insns. */
5719 if (maybe_ne (used, 0)
5720 && !emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval),
5721 NULL_RTX, parm_align, partial, reg, used - size,
5722 argblock, ARGS_SIZE_RTX (arg->locate.offset),
5723 reg_parm_stack_space,
5724 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5725 sibcall_failure = 1;
5727 /* Unless this is a partially-in-register argument, the argument is now
5728 in the stack. */
5729 if (partial == 0)
5730 arg->value = arg->stack;
5732 else
5734 /* BLKmode, at least partly to be pushed. */
5736 unsigned int parm_align;
5737 poly_int64 excess;
5738 rtx size_rtx;
5740 /* Pushing a nonscalar.
5741 If part is passed in registers, PARTIAL says how much
5742 and emit_push_insn will take care of putting it there. */
5744 /* Round its size up to a multiple
5745 of the allocation unit for arguments. */
5747 if (arg->locate.size.var != 0)
5749 excess = 0;
5750 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5752 else
5754 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5755 for BLKmode is careful to avoid it. */
5756 excess = (arg->locate.size.constant
5757 - arg_int_size_in_bytes (TREE_TYPE (pval))
5758 + partial);
5759 size_rtx = expand_expr (arg_size_in_bytes (TREE_TYPE (pval)),
5760 NULL_RTX, TYPE_MODE (sizetype),
5761 EXPAND_NORMAL);
5764 parm_align = arg->locate.boundary;
5766 /* When an argument is padded down, the block is aligned to
5767 PARM_BOUNDARY, but the actual argument isn't. */
5768 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5769 == PAD_DOWNWARD)
5771 if (arg->locate.size.var)
5772 parm_align = BITS_PER_UNIT;
5773 else
5775 unsigned int excess_align
5776 = known_alignment (excess) * BITS_PER_UNIT;
5777 if (excess_align != 0)
5778 parm_align = MIN (parm_align, excess_align);
5782 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5784 /* emit_push_insn might not work properly if arg->value and
5785 argblock + arg->locate.offset areas overlap. */
5786 rtx x = arg->value;
5787 poly_int64 i = 0;
5789 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5790 || (GET_CODE (XEXP (x, 0)) == PLUS
5791 && XEXP (XEXP (x, 0), 0) ==
5792 crtl->args.internal_arg_pointer
5793 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5795 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5796 i = rtx_to_poly_int64 (XEXP (XEXP (x, 0), 1));
5798 /* arg.locate doesn't contain the pretend_args_size offset,
5799 it's part of argblock. Ensure we don't count it in I. */
5800 if (STACK_GROWS_DOWNWARD)
5801 i -= crtl->args.pretend_args_size;
5802 else
5803 i += crtl->args.pretend_args_size;
5805 /* expand_call should ensure this. */
5806 gcc_assert (!arg->locate.offset.var
5807 && arg->locate.size.var == 0);
5808 poly_int64 size_val = rtx_to_poly_int64 (size_rtx);
5810 if (known_eq (arg->locate.offset.constant, i))
5812 /* Even though they appear to be at the same location,
5813 if part of the outgoing argument is in registers,
5814 they aren't really at the same location. Check for
5815 this by making sure that the incoming size is the
5816 same as the outgoing size. */
5817 if (maybe_ne (arg->locate.size.constant, size_val))
5818 sibcall_failure = 1;
5820 else if (maybe_in_range_p (arg->locate.offset.constant,
5821 i, size_val))
5822 sibcall_failure = 1;
5823 /* Use arg->locate.size.constant instead of size_rtx
5824 because we only care about the part of the argument
5825 on the stack. */
5826 else if (maybe_in_range_p (i, arg->locate.offset.constant,
5827 arg->locate.size.constant))
5828 sibcall_failure = 1;
5832 if (!CONST_INT_P (size_rtx) || INTVAL (size_rtx) != 0)
5833 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5834 parm_align, partial, reg, excess, argblock,
5835 ARGS_SIZE_RTX (arg->locate.offset),
5836 reg_parm_stack_space,
5837 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5839 /* Unless this is a partially-in-register argument, the argument is now
5840 in the stack.
5842 ??? Unlike the case above, in which we want the actual
5843 address of the data, so that we can load it directly into a
5844 register, here we want the address of the stack slot, so that
5845 it's properly aligned for word-by-word copying or something
5846 like that. It's not clear that this is always correct. */
5847 if (partial == 0)
5848 arg->value = arg->stack_slot;
5851 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5853 tree type = TREE_TYPE (arg->tree_value);
5854 arg->parallel_value
5855 = emit_group_load_into_temps (arg->reg, arg->value, type,
5856 int_size_in_bytes (type));
5859 /* Mark all slots this store used. */
5860 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5861 && argblock && ! variable_size && arg->stack)
5862 mark_stack_region_used (lower_bound, upper_bound);
5864 /* Once we have pushed something, pops can't safely
5865 be deferred during the rest of the arguments. */
5866 NO_DEFER_POP;
5868 /* Free any temporary slots made in processing this argument. */
5869 pop_temp_slots ();
5871 return sibcall_failure;
5874 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5876 bool
5877 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5878 const_tree type)
5880 if (!type)
5881 return false;
5883 /* If the type has variable size... */
5884 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5885 return true;
5887 /* If the type is marked as addressable (it is required
5888 to be constructed into the stack)... */
5889 if (TREE_ADDRESSABLE (type))
5890 return true;
5892 return false;
5895 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5896 takes trailing padding of a structure into account. */
5897 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5899 bool
5900 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5902 if (!type)
5903 return false;
5905 /* If the type has variable size... */
5906 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5907 return true;
5909 /* If the type is marked as addressable (it is required
5910 to be constructed into the stack)... */
5911 if (TREE_ADDRESSABLE (type))
5912 return true;
5914 if (TYPE_EMPTY_P (type))
5915 return false;
5917 /* If the padding and mode of the type is such that a copy into
5918 a register would put it into the wrong part of the register. */
5919 if (mode == BLKmode
5920 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5921 && (targetm.calls.function_arg_padding (mode, type)
5922 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5923 return true;
5925 return false;
5928 /* Tell the garbage collector about GTY markers in this source file. */
5929 #include "gt-calls.h"