Improve max_insns_skipped logic
[official-gcc.git] / gcc / calls.c
blobe7572343ba89cbcb3e56ad5c16840b4d2515aaa6
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2017 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"
58 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
59 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
61 /* Data structure and subroutines used within expand_call. */
63 struct arg_data
65 /* Tree node for this argument. */
66 tree tree_value;
67 /* Mode for value; TYPE_MODE unless promoted. */
68 machine_mode mode;
69 /* Current RTL value for argument, or 0 if it isn't precomputed. */
70 rtx value;
71 /* Initially-compute RTL value for argument; only for const functions. */
72 rtx initial_value;
73 /* Register to pass this argument in, 0 if passed on stack, or an
74 PARALLEL if the arg is to be copied into multiple non-contiguous
75 registers. */
76 rtx reg;
77 /* Register to pass this argument in when generating tail call sequence.
78 This is not the same register as for normal calls on machines with
79 register windows. */
80 rtx tail_call_reg;
81 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
82 form for emit_group_move. */
83 rtx parallel_value;
84 /* If value is passed in neither reg nor stack, this field holds a number
85 of a special slot to be used. */
86 rtx special_slot;
87 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
88 there is no such pointer. */
89 int pointer_arg;
90 /* If pointer_arg refers a structure, then pointer_offset holds an offset
91 of a pointer in this structure. */
92 int pointer_offset;
93 /* If REG was promoted from the actual mode of the argument expression,
94 indicates whether the promotion is sign- or zero-extended. */
95 int unsignedp;
96 /* Number of bytes to put in registers. 0 means put the whole arg
97 in registers. Also 0 if not passed in registers. */
98 int partial;
99 /* Nonzero if argument must be passed on stack.
100 Note that some arguments may be passed on the stack
101 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
102 pass_on_stack identifies arguments that *cannot* go in registers. */
103 int pass_on_stack;
104 /* Some fields packaged up for locate_and_pad_parm. */
105 struct locate_and_pad_arg_data locate;
106 /* Location on the stack at which parameter should be stored. The store
107 has already been done if STACK == VALUE. */
108 rtx stack;
109 /* Location on the stack of the start of this argument slot. This can
110 differ from STACK if this arg pads downward. This location is known
111 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
112 rtx stack_slot;
113 /* Place that this stack area has been saved, if needed. */
114 rtx save_area;
115 /* If an argument's alignment does not permit direct copying into registers,
116 copy in smaller-sized pieces into pseudos. These are stored in a
117 block pointed to by this field. The next field says how many
118 word-sized pseudos we made. */
119 rtx *aligned_regs;
120 int n_aligned_regs;
123 /* A vector of one char per byte of stack space. A byte if nonzero if
124 the corresponding stack location has been used.
125 This vector is used to prevent a function call within an argument from
126 clobbering any stack already set up. */
127 static char *stack_usage_map;
129 /* Size of STACK_USAGE_MAP. */
130 static int highest_outgoing_arg_in_use;
132 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
133 stack location's tail call argument has been already stored into the stack.
134 This bitmap is used to prevent sibling call optimization if function tries
135 to use parent's incoming argument slots when they have been already
136 overwritten with tail call arguments. */
137 static sbitmap stored_args_map;
139 /* stack_arg_under_construction is nonzero when an argument may be
140 initialized with a constructor call (including a C function that
141 returns a BLKmode struct) and expand_call must take special action
142 to make sure the object being constructed does not overlap the
143 argument list for the constructor call. */
144 static int stack_arg_under_construction;
146 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
147 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
148 cumulative_args_t);
149 static void precompute_register_parameters (int, struct arg_data *, int *);
150 static void store_bounds (struct arg_data *, struct arg_data *);
151 static int store_one_arg (struct arg_data *, rtx, int, int, int);
152 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
153 static int finalize_must_preallocate (int, int, struct arg_data *,
154 struct args_size *);
155 static void precompute_arguments (int, struct arg_data *);
156 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
157 static void initialize_argument_information (int, struct arg_data *,
158 struct args_size *, int,
159 tree, tree,
160 tree, tree, cumulative_args_t, int,
161 rtx *, int *, int *, int *,
162 bool *, bool);
163 static void compute_argument_addresses (struct arg_data *, rtx, int);
164 static rtx rtx_for_function_call (tree, tree);
165 static void load_register_parameters (struct arg_data *, int, rtx *, int,
166 int, int *);
167 static int special_function_p (const_tree, int);
168 static int check_sibcall_argument_overlap_1 (rtx);
169 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
171 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
172 unsigned int);
173 static tree split_complex_types (tree);
175 #ifdef REG_PARM_STACK_SPACE
176 static rtx save_fixed_argument_area (int, rtx, int *, int *);
177 static void restore_fixed_argument_area (rtx, rtx, int, int);
178 #endif
180 /* Force FUNEXP into a form suitable for the address of a CALL,
181 and return that as an rtx. Also load the static chain register
182 if FNDECL is a nested function.
184 CALL_FUSAGE points to a variable holding the prospective
185 CALL_INSN_FUNCTION_USAGE information. */
188 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
189 rtx *call_fusage, int reg_parm_seen, int flags)
191 /* Make a valid memory address and copy constants through pseudo-regs,
192 but not for a constant address if -fno-function-cse. */
193 if (GET_CODE (funexp) != SYMBOL_REF)
195 /* If it's an indirect call by descriptor, generate code to perform
196 runtime identification of the pointer and load the descriptor. */
197 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
199 const int bit_val = targetm.calls.custom_function_descriptors;
200 rtx call_lab = gen_label_rtx ();
202 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
203 fndecl_or_type
204 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
205 fndecl_or_type);
206 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
207 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
209 if (GET_MODE (funexp) != Pmode)
210 funexp = convert_memory_address (Pmode, funexp);
212 /* Avoid long live ranges around function calls. */
213 funexp = copy_to_mode_reg (Pmode, funexp);
215 if (REG_P (chain))
216 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
218 /* Emit the runtime identification pattern. */
219 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
220 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
221 call_lab);
223 /* Statically predict the branch to very likely taken. */
224 rtx_insn *insn = get_last_insn ();
225 if (JUMP_P (insn))
226 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
228 /* Load the descriptor. */
229 rtx mem = gen_rtx_MEM (ptr_mode,
230 plus_constant (Pmode, funexp, - bit_val));
231 MEM_NOTRAP_P (mem) = 1;
232 mem = convert_memory_address (Pmode, mem);
233 emit_move_insn (chain, mem);
235 mem = gen_rtx_MEM (ptr_mode,
236 plus_constant (Pmode, funexp,
237 POINTER_SIZE / BITS_PER_UNIT
238 - bit_val));
239 MEM_NOTRAP_P (mem) = 1;
240 mem = convert_memory_address (Pmode, mem);
241 emit_move_insn (funexp, mem);
243 emit_label (call_lab);
245 if (REG_P (chain))
247 use_reg (call_fusage, chain);
248 STATIC_CHAIN_REG_P (chain) = 1;
251 /* Make sure we're not going to be overwritten below. */
252 gcc_assert (!static_chain_value);
255 /* If we are using registers for parameters, force the
256 function address into a register now. */
257 funexp = ((reg_parm_seen
258 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
259 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
260 : memory_address (FUNCTION_MODE, funexp));
262 else
264 /* funexp could be a SYMBOL_REF represents a function pointer which is
265 of ptr_mode. In this case, it should be converted into address mode
266 to be a valid address for memory rtx pattern. See PR 64971. */
267 if (GET_MODE (funexp) != Pmode)
268 funexp = convert_memory_address (Pmode, funexp);
270 if (!(flags & ECF_SIBCALL))
272 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
273 funexp = force_reg (Pmode, funexp);
277 if (static_chain_value != 0
278 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
279 || DECL_STATIC_CHAIN (fndecl_or_type)))
281 rtx chain;
283 chain = targetm.calls.static_chain (fndecl_or_type, false);
284 static_chain_value = convert_memory_address (Pmode, static_chain_value);
286 emit_move_insn (chain, static_chain_value);
287 if (REG_P (chain))
289 use_reg (call_fusage, chain);
290 STATIC_CHAIN_REG_P (chain) = 1;
294 return funexp;
297 /* Generate instructions to call function FUNEXP,
298 and optionally pop the results.
299 The CALL_INSN is the first insn generated.
301 FNDECL is the declaration node of the function. This is given to the
302 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
303 its own args.
305 FUNTYPE is the data type of the function. This is given to the hook
306 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
307 own args. We used to allow an identifier for library functions, but
308 that doesn't work when the return type is an aggregate type and the
309 calling convention says that the pointer to this aggregate is to be
310 popped by the callee.
312 STACK_SIZE is the number of bytes of arguments on the stack,
313 ROUNDED_STACK_SIZE is that number rounded up to
314 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
315 both to put into the call insn and to generate explicit popping
316 code if necessary.
318 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
319 It is zero if this call doesn't want a structure value.
321 NEXT_ARG_REG is the rtx that results from executing
322 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
323 just after all the args have had their registers assigned.
324 This could be whatever you like, but normally it is the first
325 arg-register beyond those used for args in this call,
326 or 0 if all the arg-registers are used in this call.
327 It is passed on to `gen_call' so you can put this info in the call insn.
329 VALREG is a hard register in which a value is returned,
330 or 0 if the call does not return a value.
332 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
333 the args to this call were processed.
334 We restore `inhibit_defer_pop' to that value.
336 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
337 denote registers used by the called function. */
339 static void
340 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
341 tree funtype ATTRIBUTE_UNUSED,
342 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
343 HOST_WIDE_INT rounded_stack_size,
344 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
345 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
346 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
347 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
349 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
350 rtx call, funmem, pat;
351 int already_popped = 0;
352 HOST_WIDE_INT n_popped = 0;
354 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
355 patterns exist). Any popping that the callee does on return will
356 be from our caller's frame rather than ours. */
357 if (!(ecf_flags & ECF_SIBCALL))
359 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
361 #ifdef CALL_POPS_ARGS
362 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
363 #endif
366 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
367 and we don't want to load it into a register as an optimization,
368 because prepare_call_address already did it if it should be done. */
369 if (GET_CODE (funexp) != SYMBOL_REF)
370 funexp = memory_address (FUNCTION_MODE, funexp);
372 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
373 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
375 tree t = fndecl;
377 /* Although a built-in FUNCTION_DECL and its non-__builtin
378 counterpart compare equal and get a shared mem_attrs, they
379 produce different dump output in compare-debug compilations,
380 if an entry gets garbage collected in one compilation, then
381 adds a different (but equivalent) entry, while the other
382 doesn't run the garbage collector at the same spot and then
383 shares the mem_attr with the equivalent entry. */
384 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
386 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
387 if (t2)
388 t = t2;
391 set_mem_expr (funmem, t);
393 else if (fntree)
394 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
396 if (ecf_flags & ECF_SIBCALL)
398 if (valreg)
399 pat = targetm.gen_sibcall_value (valreg, funmem,
400 rounded_stack_size_rtx,
401 next_arg_reg, NULL_RTX);
402 else
403 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
404 next_arg_reg, GEN_INT (struct_value_size));
406 /* If the target has "call" or "call_value" insns, then prefer them
407 if no arguments are actually popped. If the target does not have
408 "call" or "call_value" insns, then we must use the popping versions
409 even if the call has no arguments to pop. */
410 else if (n_popped > 0
411 || !(valreg
412 ? targetm.have_call_value ()
413 : targetm.have_call ()))
415 rtx n_pop = GEN_INT (n_popped);
417 /* If this subroutine pops its own args, record that in the call insn
418 if possible, for the sake of frame pointer elimination. */
420 if (valreg)
421 pat = targetm.gen_call_value_pop (valreg, funmem,
422 rounded_stack_size_rtx,
423 next_arg_reg, n_pop);
424 else
425 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
426 next_arg_reg, n_pop);
428 already_popped = 1;
430 else
432 if (valreg)
433 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
434 next_arg_reg, NULL_RTX);
435 else
436 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
437 GEN_INT (struct_value_size));
439 emit_insn (pat);
441 /* Find the call we just emitted. */
442 rtx_call_insn *call_insn = last_call_insn ();
444 /* Some target create a fresh MEM instead of reusing the one provided
445 above. Set its MEM_EXPR. */
446 call = get_call_rtx_from (call_insn);
447 if (call
448 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
449 && MEM_EXPR (funmem) != NULL_TREE)
450 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
452 /* Mark instrumented calls. */
453 if (call && fntree)
454 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
456 /* Put the register usage information there. */
457 add_function_usage_to (call_insn, call_fusage);
459 /* If this is a const call, then set the insn's unchanging bit. */
460 if (ecf_flags & ECF_CONST)
461 RTL_CONST_CALL_P (call_insn) = 1;
463 /* If this is a pure call, then set the insn's unchanging bit. */
464 if (ecf_flags & ECF_PURE)
465 RTL_PURE_CALL_P (call_insn) = 1;
467 /* If this is a const call, then set the insn's unchanging bit. */
468 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
469 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
471 /* Create a nothrow REG_EH_REGION note, if needed. */
472 make_reg_eh_region_note (call_insn, ecf_flags, 0);
474 if (ecf_flags & ECF_NORETURN)
475 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
477 if (ecf_flags & ECF_RETURNS_TWICE)
479 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
480 cfun->calls_setjmp = 1;
483 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
485 /* Restore this now, so that we do defer pops for this call's args
486 if the context of the call as a whole permits. */
487 inhibit_defer_pop = old_inhibit_defer_pop;
489 if (n_popped > 0)
491 if (!already_popped)
492 CALL_INSN_FUNCTION_USAGE (call_insn)
493 = gen_rtx_EXPR_LIST (VOIDmode,
494 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
495 CALL_INSN_FUNCTION_USAGE (call_insn));
496 rounded_stack_size -= n_popped;
497 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
498 stack_pointer_delta -= n_popped;
500 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
502 /* If popup is needed, stack realign must use DRAP */
503 if (SUPPORTS_STACK_ALIGNMENT)
504 crtl->need_drap = true;
506 /* For noreturn calls when not accumulating outgoing args force
507 REG_ARGS_SIZE note to prevent crossjumping of calls with different
508 args sizes. */
509 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
510 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
512 if (!ACCUMULATE_OUTGOING_ARGS)
514 /* If returning from the subroutine does not automatically pop the args,
515 we need an instruction to pop them sooner or later.
516 Perhaps do it now; perhaps just record how much space to pop later.
518 If returning from the subroutine does pop the args, indicate that the
519 stack pointer will be changed. */
521 if (rounded_stack_size != 0)
523 if (ecf_flags & ECF_NORETURN)
524 /* Just pretend we did the pop. */
525 stack_pointer_delta -= rounded_stack_size;
526 else if (flag_defer_pop && inhibit_defer_pop == 0
527 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
528 pending_stack_adjust += rounded_stack_size;
529 else
530 adjust_stack (rounded_stack_size_rtx);
533 /* When we accumulate outgoing args, we must avoid any stack manipulations.
534 Restore the stack pointer to its original value now. Usually
535 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
536 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
537 popping variants of functions exist as well.
539 ??? We may optimize similar to defer_pop above, but it is
540 probably not worthwhile.
542 ??? It will be worthwhile to enable combine_stack_adjustments even for
543 such machines. */
544 else if (n_popped)
545 anti_adjust_stack (GEN_INT (n_popped));
548 /* Determine if the function identified by FNDECL is one with
549 special properties we wish to know about. Modify FLAGS accordingly.
551 For example, if the function might return more than one time (setjmp), then
552 set ECF_RETURNS_TWICE.
554 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
555 space from the stack such as alloca. */
557 static int
558 special_function_p (const_tree fndecl, int flags)
560 tree name_decl = DECL_NAME (fndecl);
562 /* For instrumentation clones we want to derive flags
563 from the original name. */
564 if (cgraph_node::get (fndecl)
565 && cgraph_node::get (fndecl)->instrumentation_clone)
566 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
568 if (fndecl && name_decl
569 && IDENTIFIER_LENGTH (name_decl) <= 11
570 /* Exclude functions not at the file scope, or not `extern',
571 since they are not the magic functions we would otherwise
572 think they are.
573 FIXME: this should be handled with attributes, not with this
574 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
575 because you can declare fork() inside a function if you
576 wish. */
577 && (DECL_CONTEXT (fndecl) == NULL_TREE
578 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
579 && TREE_PUBLIC (fndecl))
581 const char *name = IDENTIFIER_POINTER (name_decl);
582 const char *tname = name;
584 /* We assume that alloca will always be called by name. It
585 makes no sense to pass it as a pointer-to-function to
586 anything that does not understand its behavior. */
587 if (IDENTIFIER_LENGTH (name_decl) == 6
588 && name[0] == 'a'
589 && ! strcmp (name, "alloca"))
590 flags |= ECF_MAY_BE_ALLOCA;
592 /* Disregard prefix _ or __. */
593 if (name[0] == '_')
595 if (name[1] == '_')
596 tname += 2;
597 else
598 tname += 1;
601 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
602 if (! strcmp (tname, "setjmp")
603 || ! strcmp (tname, "sigsetjmp")
604 || ! strcmp (name, "savectx")
605 || ! strcmp (name, "vfork")
606 || ! strcmp (name, "getcontext"))
607 flags |= ECF_RETURNS_TWICE;
610 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
611 switch (DECL_FUNCTION_CODE (fndecl))
613 case BUILT_IN_ALLOCA:
614 case BUILT_IN_ALLOCA_WITH_ALIGN:
615 flags |= ECF_MAY_BE_ALLOCA;
616 break;
617 default:
618 break;
621 return flags;
624 /* Similar to special_function_p; return a set of ERF_ flags for the
625 function FNDECL. */
626 static int
627 decl_return_flags (tree fndecl)
629 tree attr;
630 tree type = TREE_TYPE (fndecl);
631 if (!type)
632 return 0;
634 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
635 if (!attr)
636 return 0;
638 attr = TREE_VALUE (TREE_VALUE (attr));
639 if (!attr || TREE_STRING_LENGTH (attr) < 1)
640 return 0;
642 switch (TREE_STRING_POINTER (attr)[0])
644 case '1':
645 case '2':
646 case '3':
647 case '4':
648 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
650 case 'm':
651 return ERF_NOALIAS;
653 case '.':
654 default:
655 return 0;
659 /* Return nonzero when FNDECL represents a call to setjmp. */
662 setjmp_call_p (const_tree fndecl)
664 if (DECL_IS_RETURNS_TWICE (fndecl))
665 return ECF_RETURNS_TWICE;
666 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
670 /* Return true if STMT may be an alloca call. */
672 bool
673 gimple_maybe_alloca_call_p (const gimple *stmt)
675 tree fndecl;
677 if (!is_gimple_call (stmt))
678 return false;
680 fndecl = gimple_call_fndecl (stmt);
681 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
682 return true;
684 return false;
687 /* Return true if STMT is a builtin alloca call. */
689 bool
690 gimple_alloca_call_p (const gimple *stmt)
692 tree fndecl;
694 if (!is_gimple_call (stmt))
695 return false;
697 fndecl = gimple_call_fndecl (stmt);
698 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
699 switch (DECL_FUNCTION_CODE (fndecl))
701 case BUILT_IN_ALLOCA:
702 case BUILT_IN_ALLOCA_WITH_ALIGN:
703 return true;
704 default:
705 break;
708 return false;
711 /* Return true when exp contains a builtin alloca call. */
713 bool
714 alloca_call_p (const_tree exp)
716 tree fndecl;
717 if (TREE_CODE (exp) == CALL_EXPR
718 && (fndecl = get_callee_fndecl (exp))
719 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
720 switch (DECL_FUNCTION_CODE (fndecl))
722 case BUILT_IN_ALLOCA:
723 case BUILT_IN_ALLOCA_WITH_ALIGN:
724 return true;
725 default:
726 break;
729 return false;
732 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
733 function. Return FALSE otherwise. */
735 static bool
736 is_tm_builtin (const_tree fndecl)
738 if (fndecl == NULL)
739 return false;
741 if (decl_is_tm_clone (fndecl))
742 return true;
744 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
746 switch (DECL_FUNCTION_CODE (fndecl))
748 case BUILT_IN_TM_COMMIT:
749 case BUILT_IN_TM_COMMIT_EH:
750 case BUILT_IN_TM_ABORT:
751 case BUILT_IN_TM_IRREVOCABLE:
752 case BUILT_IN_TM_GETTMCLONE_IRR:
753 case BUILT_IN_TM_MEMCPY:
754 case BUILT_IN_TM_MEMMOVE:
755 case BUILT_IN_TM_MEMSET:
756 CASE_BUILT_IN_TM_STORE (1):
757 CASE_BUILT_IN_TM_STORE (2):
758 CASE_BUILT_IN_TM_STORE (4):
759 CASE_BUILT_IN_TM_STORE (8):
760 CASE_BUILT_IN_TM_STORE (FLOAT):
761 CASE_BUILT_IN_TM_STORE (DOUBLE):
762 CASE_BUILT_IN_TM_STORE (LDOUBLE):
763 CASE_BUILT_IN_TM_STORE (M64):
764 CASE_BUILT_IN_TM_STORE (M128):
765 CASE_BUILT_IN_TM_STORE (M256):
766 CASE_BUILT_IN_TM_LOAD (1):
767 CASE_BUILT_IN_TM_LOAD (2):
768 CASE_BUILT_IN_TM_LOAD (4):
769 CASE_BUILT_IN_TM_LOAD (8):
770 CASE_BUILT_IN_TM_LOAD (FLOAT):
771 CASE_BUILT_IN_TM_LOAD (DOUBLE):
772 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
773 CASE_BUILT_IN_TM_LOAD (M64):
774 CASE_BUILT_IN_TM_LOAD (M128):
775 CASE_BUILT_IN_TM_LOAD (M256):
776 case BUILT_IN_TM_LOG:
777 case BUILT_IN_TM_LOG_1:
778 case BUILT_IN_TM_LOG_2:
779 case BUILT_IN_TM_LOG_4:
780 case BUILT_IN_TM_LOG_8:
781 case BUILT_IN_TM_LOG_FLOAT:
782 case BUILT_IN_TM_LOG_DOUBLE:
783 case BUILT_IN_TM_LOG_LDOUBLE:
784 case BUILT_IN_TM_LOG_M64:
785 case BUILT_IN_TM_LOG_M128:
786 case BUILT_IN_TM_LOG_M256:
787 return true;
788 default:
789 break;
792 return false;
795 /* Detect flags (function attributes) from the function decl or type node. */
798 flags_from_decl_or_type (const_tree exp)
800 int flags = 0;
802 if (DECL_P (exp))
804 /* The function exp may have the `malloc' attribute. */
805 if (DECL_IS_MALLOC (exp))
806 flags |= ECF_MALLOC;
808 /* The function exp may have the `returns_twice' attribute. */
809 if (DECL_IS_RETURNS_TWICE (exp))
810 flags |= ECF_RETURNS_TWICE;
812 /* Process the pure and const attributes. */
813 if (TREE_READONLY (exp))
814 flags |= ECF_CONST;
815 if (DECL_PURE_P (exp))
816 flags |= ECF_PURE;
817 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
818 flags |= ECF_LOOPING_CONST_OR_PURE;
820 if (DECL_IS_NOVOPS (exp))
821 flags |= ECF_NOVOPS;
822 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
823 flags |= ECF_LEAF;
824 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
825 flags |= ECF_COLD;
827 if (TREE_NOTHROW (exp))
828 flags |= ECF_NOTHROW;
830 if (flag_tm)
832 if (is_tm_builtin (exp))
833 flags |= ECF_TM_BUILTIN;
834 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
835 || lookup_attribute ("transaction_pure",
836 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
837 flags |= ECF_TM_PURE;
840 flags = special_function_p (exp, flags);
842 else if (TYPE_P (exp))
844 if (TYPE_READONLY (exp))
845 flags |= ECF_CONST;
847 if (flag_tm
848 && ((flags & ECF_CONST) != 0
849 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
850 flags |= ECF_TM_PURE;
852 else
853 gcc_unreachable ();
855 if (TREE_THIS_VOLATILE (exp))
857 flags |= ECF_NORETURN;
858 if (flags & (ECF_CONST|ECF_PURE))
859 flags |= ECF_LOOPING_CONST_OR_PURE;
862 return flags;
865 /* Detect flags from a CALL_EXPR. */
868 call_expr_flags (const_tree t)
870 int flags;
871 tree decl = get_callee_fndecl (t);
873 if (decl)
874 flags = flags_from_decl_or_type (decl);
875 else if (CALL_EXPR_FN (t) == NULL_TREE)
876 flags = internal_fn_flags (CALL_EXPR_IFN (t));
877 else
879 tree type = TREE_TYPE (CALL_EXPR_FN (t));
880 if (type && TREE_CODE (type) == POINTER_TYPE)
881 flags = flags_from_decl_or_type (TREE_TYPE (type));
882 else
883 flags = 0;
884 if (CALL_EXPR_BY_DESCRIPTOR (t))
885 flags |= ECF_BY_DESCRIPTOR;
888 return flags;
891 /* Return true if TYPE should be passed by invisible reference. */
893 bool
894 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
895 tree type, bool named_arg)
897 if (type)
899 /* If this type contains non-trivial constructors, then it is
900 forbidden for the middle-end to create any new copies. */
901 if (TREE_ADDRESSABLE (type))
902 return true;
904 /* GCC post 3.4 passes *all* variable sized types by reference. */
905 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
906 return true;
908 /* If a record type should be passed the same as its first (and only)
909 member, use the type and mode of that member. */
910 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
912 type = TREE_TYPE (first_field (type));
913 mode = TYPE_MODE (type);
917 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
918 type, named_arg);
921 /* Return true if TYPE, which is passed by reference, should be callee
922 copied instead of caller copied. */
924 bool
925 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
926 tree type, bool named_arg)
928 if (type && TREE_ADDRESSABLE (type))
929 return false;
930 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
931 named_arg);
935 /* Precompute all register parameters as described by ARGS, storing values
936 into fields within the ARGS array.
938 NUM_ACTUALS indicates the total number elements in the ARGS array.
940 Set REG_PARM_SEEN if we encounter a register parameter. */
942 static void
943 precompute_register_parameters (int num_actuals, struct arg_data *args,
944 int *reg_parm_seen)
946 int i;
948 *reg_parm_seen = 0;
950 for (i = 0; i < num_actuals; i++)
951 if (args[i].reg != 0 && ! args[i].pass_on_stack)
953 *reg_parm_seen = 1;
955 if (args[i].value == 0)
957 push_temp_slots ();
958 args[i].value = expand_normal (args[i].tree_value);
959 preserve_temp_slots (args[i].value);
960 pop_temp_slots ();
963 /* If we are to promote the function arg to a wider mode,
964 do it now. */
966 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
967 args[i].value
968 = convert_modes (args[i].mode,
969 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
970 args[i].value, args[i].unsignedp);
972 /* If the value is a non-legitimate constant, force it into a
973 pseudo now. TLS symbols sometimes need a call to resolve. */
974 if (CONSTANT_P (args[i].value)
975 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
976 args[i].value = force_reg (args[i].mode, args[i].value);
978 /* If we're going to have to load the value by parts, pull the
979 parts into pseudos. The part extraction process can involve
980 non-trivial computation. */
981 if (GET_CODE (args[i].reg) == PARALLEL)
983 tree type = TREE_TYPE (args[i].tree_value);
984 args[i].parallel_value
985 = emit_group_load_into_temps (args[i].reg, args[i].value,
986 type, int_size_in_bytes (type));
989 /* If the value is expensive, and we are inside an appropriately
990 short loop, put the value into a pseudo and then put the pseudo
991 into the hard reg.
993 For small register classes, also do this if this call uses
994 register parameters. This is to avoid reload conflicts while
995 loading the parameters registers. */
997 else if ((! (REG_P (args[i].value)
998 || (GET_CODE (args[i].value) == SUBREG
999 && REG_P (SUBREG_REG (args[i].value)))))
1000 && args[i].mode != BLKmode
1001 && (set_src_cost (args[i].value, args[i].mode,
1002 optimize_insn_for_speed_p ())
1003 > COSTS_N_INSNS (1))
1004 && ((*reg_parm_seen
1005 && targetm.small_register_classes_for_mode_p (args[i].mode))
1006 || optimize))
1007 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1011 #ifdef REG_PARM_STACK_SPACE
1013 /* The argument list is the property of the called routine and it
1014 may clobber it. If the fixed area has been used for previous
1015 parameters, we must save and restore it. */
1017 static rtx
1018 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1020 int low;
1021 int high;
1023 /* Compute the boundary of the area that needs to be saved, if any. */
1024 high = reg_parm_stack_space;
1025 if (ARGS_GROW_DOWNWARD)
1026 high += 1;
1028 if (high > highest_outgoing_arg_in_use)
1029 high = highest_outgoing_arg_in_use;
1031 for (low = 0; low < high; low++)
1032 if (stack_usage_map[low] != 0)
1034 int num_to_save;
1035 machine_mode save_mode;
1036 int delta;
1037 rtx addr;
1038 rtx stack_area;
1039 rtx save_area;
1041 while (stack_usage_map[--high] == 0)
1044 *low_to_save = low;
1045 *high_to_save = high;
1047 num_to_save = high - low + 1;
1049 /* If we don't have the required alignment, must do this
1050 in BLKmode. */
1051 scalar_int_mode imode;
1052 if (int_mode_for_size (num_to_save * BITS_PER_UNIT, 1).exists (&imode)
1053 && (low & (MIN (GET_MODE_SIZE (imode),
1054 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)) == 0)
1055 save_mode = imode;
1056 else
1057 save_mode = BLKmode;
1059 if (ARGS_GROW_DOWNWARD)
1060 delta = -high;
1061 else
1062 delta = low;
1064 addr = plus_constant (Pmode, argblock, delta);
1065 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1067 set_mem_align (stack_area, PARM_BOUNDARY);
1068 if (save_mode == BLKmode)
1070 save_area = assign_stack_temp (BLKmode, num_to_save);
1071 emit_block_move (validize_mem (save_area), stack_area,
1072 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1074 else
1076 save_area = gen_reg_rtx (save_mode);
1077 emit_move_insn (save_area, stack_area);
1080 return save_area;
1083 return NULL_RTX;
1086 static void
1087 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1089 machine_mode save_mode = GET_MODE (save_area);
1090 int delta;
1091 rtx addr, stack_area;
1093 if (ARGS_GROW_DOWNWARD)
1094 delta = -high_to_save;
1095 else
1096 delta = low_to_save;
1098 addr = plus_constant (Pmode, argblock, delta);
1099 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1100 set_mem_align (stack_area, PARM_BOUNDARY);
1102 if (save_mode != BLKmode)
1103 emit_move_insn (stack_area, save_area);
1104 else
1105 emit_block_move (stack_area, validize_mem (save_area),
1106 GEN_INT (high_to_save - low_to_save + 1),
1107 BLOCK_OP_CALL_PARM);
1109 #endif /* REG_PARM_STACK_SPACE */
1111 /* If any elements in ARGS refer to parameters that are to be passed in
1112 registers, but not in memory, and whose alignment does not permit a
1113 direct copy into registers. Copy the values into a group of pseudos
1114 which we will later copy into the appropriate hard registers.
1116 Pseudos for each unaligned argument will be stored into the array
1117 args[argnum].aligned_regs. The caller is responsible for deallocating
1118 the aligned_regs array if it is nonzero. */
1120 static void
1121 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1123 int i, j;
1125 for (i = 0; i < num_actuals; i++)
1126 if (args[i].reg != 0 && ! args[i].pass_on_stack
1127 && GET_CODE (args[i].reg) != PARALLEL
1128 && args[i].mode == BLKmode
1129 && MEM_P (args[i].value)
1130 && (MEM_ALIGN (args[i].value)
1131 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1133 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1134 int endian_correction = 0;
1136 if (args[i].partial)
1138 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1139 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1141 else
1143 args[i].n_aligned_regs
1144 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1147 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1149 /* Structures smaller than a word are normally aligned to the
1150 least significant byte. On a BYTES_BIG_ENDIAN machine,
1151 this means we must skip the empty high order bytes when
1152 calculating the bit offset. */
1153 if (bytes < UNITS_PER_WORD
1154 #ifdef BLOCK_REG_PADDING
1155 && (BLOCK_REG_PADDING (args[i].mode,
1156 TREE_TYPE (args[i].tree_value), 1)
1157 == PAD_DOWNWARD)
1158 #else
1159 && BYTES_BIG_ENDIAN
1160 #endif
1162 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1164 for (j = 0; j < args[i].n_aligned_regs; j++)
1166 rtx reg = gen_reg_rtx (word_mode);
1167 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1168 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1170 args[i].aligned_regs[j] = reg;
1171 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1172 word_mode, word_mode, false, NULL);
1174 /* There is no need to restrict this code to loading items
1175 in TYPE_ALIGN sized hunks. The bitfield instructions can
1176 load up entire word sized registers efficiently.
1178 ??? This may not be needed anymore.
1179 We use to emit a clobber here but that doesn't let later
1180 passes optimize the instructions we emit. By storing 0 into
1181 the register later passes know the first AND to zero out the
1182 bitfield being set in the register is unnecessary. The store
1183 of 0 will be deleted as will at least the first AND. */
1185 emit_move_insn (reg, const0_rtx);
1187 bytes -= bitsize / BITS_PER_UNIT;
1188 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1189 word_mode, word, false);
1194 /* The limit set by -Walloc-larger-than=. */
1195 static GTY(()) tree alloc_object_size_limit;
1197 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1198 setting if the option is specified, or to the maximum object size if it
1199 is not. Return the initialized value. */
1201 static tree
1202 alloc_max_size (void)
1204 if (!alloc_object_size_limit)
1206 alloc_object_size_limit = TYPE_MAX_VALUE (ssizetype);
1208 if (warn_alloc_size_limit)
1210 char *end = NULL;
1211 errno = 0;
1212 unsigned HOST_WIDE_INT unit = 1;
1213 unsigned HOST_WIDE_INT limit
1214 = strtoull (warn_alloc_size_limit, &end, 10);
1216 if (!errno)
1218 if (end && *end)
1220 /* Numeric option arguments are at most INT_MAX. Make it
1221 possible to specify a larger value by accepting common
1222 suffixes. */
1223 if (!strcmp (end, "kB"))
1224 unit = 1000;
1225 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1226 unit = 1024;
1227 else if (!strcmp (end, "MB"))
1228 unit = HOST_WIDE_INT_UC (1000) * 1000;
1229 else if (!strcasecmp (end, "MiB"))
1230 unit = HOST_WIDE_INT_UC (1024) * 1024;
1231 else if (!strcasecmp (end, "GB"))
1232 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000;
1233 else if (!strcasecmp (end, "GiB"))
1234 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024;
1235 else if (!strcasecmp (end, "TB"))
1236 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000;
1237 else if (!strcasecmp (end, "TiB"))
1238 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024;
1239 else if (!strcasecmp (end, "PB"))
1240 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000;
1241 else if (!strcasecmp (end, "PiB"))
1242 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024;
1243 else if (!strcasecmp (end, "EB"))
1244 unit = HOST_WIDE_INT_UC (1000) * 1000 * 1000 * 1000 * 1000
1245 * 1000;
1246 else if (!strcasecmp (end, "EiB"))
1247 unit = HOST_WIDE_INT_UC (1024) * 1024 * 1024 * 1024 * 1024
1248 * 1024;
1249 else
1250 unit = 0;
1253 if (unit)
1255 wide_int w = wi::uhwi (limit, HOST_BITS_PER_WIDE_INT + 64);
1256 w *= unit;
1257 if (wi::ltu_p (w, alloc_object_size_limit))
1258 alloc_object_size_limit = wide_int_to_tree (ssizetype, w);
1263 return alloc_object_size_limit;
1266 /* Return true when EXP's range can be determined and set RANGE[] to it
1267 after adjusting it if necessary to make EXP a valid size argument to
1268 an allocation function declared with attribute alloc_size (whose
1269 argument may be signed), or to a string manipulation function like
1270 memset. */
1272 bool
1273 get_size_range (tree exp, tree range[2])
1275 if (tree_fits_uhwi_p (exp))
1277 /* EXP is a constant. */
1278 range[0] = range[1] = exp;
1279 return true;
1282 wide_int min, max;
1283 enum value_range_type range_type
1284 = ((TREE_CODE (exp) == SSA_NAME && INTEGRAL_TYPE_P (TREE_TYPE (exp)))
1285 ? get_range_info (exp, &min, &max) : VR_VARYING);
1287 if (range_type == VR_VARYING)
1289 /* No range information available. */
1290 range[0] = NULL_TREE;
1291 range[1] = NULL_TREE;
1292 return false;
1295 tree exptype = TREE_TYPE (exp);
1296 unsigned expprec = TYPE_PRECISION (exptype);
1297 wide_int wzero = wi::zero (expprec);
1298 wide_int wmaxval = wide_int (TYPE_MAX_VALUE (exptype));
1300 bool signed_p = !TYPE_UNSIGNED (exptype);
1302 if (range_type == VR_ANTI_RANGE)
1304 if (signed_p)
1306 if (wi::les_p (max, wzero))
1308 /* EXP is not in a strictly negative range. That means
1309 it must be in some (not necessarily strictly) positive
1310 range which includes zero. Since in signed to unsigned
1311 conversions negative values end up converted to large
1312 positive values, and otherwise they are not valid sizes,
1313 the resulting range is in both cases [0, TYPE_MAX]. */
1314 min = wzero;
1315 max = wmaxval;
1317 else if (wi::les_p (min - 1, wzero))
1319 /* EXP is not in a negative-positive range. That means EXP
1320 is either negative, or greater than max. Since negative
1321 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1322 min = max + 1;
1323 max = wmaxval;
1325 else
1327 max = min - 1;
1328 min = wzero;
1331 else if (wi::eq_p (wzero, min - 1))
1333 /* EXP is unsigned and not in the range [1, MAX]. That means
1334 it's either zero or greater than MAX. Even though 0 would
1335 normally be detected by -Walloc-zero set the range to
1336 [MAX, TYPE_MAX] so that when MAX is greater than the limit
1337 the whole range is diagnosed. */
1338 min = max + 1;
1339 max = wmaxval;
1341 else
1343 max = min - 1;
1344 min = wzero;
1348 range[0] = wide_int_to_tree (exptype, min);
1349 range[1] = wide_int_to_tree (exptype, max);
1351 return true;
1354 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1355 whose argument numbers given by IDX with values given by ARGS exceed
1356 the maximum object size or cause an unsigned oveflow (wrapping) when
1357 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1358 may be null for functions like malloc, and non-null for those like
1359 calloc that are decorated with a two-argument attribute alloc_size. */
1361 void
1362 maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1364 /* The range each of the (up to) two arguments is known to be in. */
1365 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1367 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1368 tree maxobjsize = alloc_max_size ();
1370 location_t loc = EXPR_LOCATION (exp);
1372 bool warned = false;
1374 /* Validate each argument individually. */
1375 for (unsigned i = 0; i != 2 && args[i]; ++i)
1377 if (TREE_CODE (args[i]) == INTEGER_CST)
1379 argrange[i][0] = args[i];
1380 argrange[i][1] = args[i];
1382 if (tree_int_cst_lt (args[i], integer_zero_node))
1384 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1385 "%Kargument %i value %qE is negative",
1386 exp, idx[i] + 1, args[i]);
1388 else if (integer_zerop (args[i]))
1390 /* Avoid issuing -Walloc-zero for allocation functions other
1391 than __builtin_alloca that are declared with attribute
1392 returns_nonnull because there's no portability risk. This
1393 avoids warning for such calls to libiberty's xmalloc and
1394 friends.
1395 Also avoid issuing the warning for calls to function named
1396 "alloca". */
1397 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1398 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1399 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1400 && !lookup_attribute ("returns_nonnull",
1401 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1402 warned = warning_at (loc, OPT_Walloc_zero,
1403 "%Kargument %i value is zero",
1404 exp, idx[i] + 1);
1406 else if (tree_int_cst_lt (maxobjsize, args[i]))
1408 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1409 mode and with -fno-exceptions as a way to indicate array
1410 size overflow. There's no good way to detect C++98 here
1411 so avoid diagnosing these calls for all C++ modes. */
1412 if (i == 0
1413 && !args[1]
1414 && lang_GNU_CXX ()
1415 && DECL_IS_OPERATOR_NEW (fn)
1416 && integer_all_onesp (args[i]))
1417 continue;
1419 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1420 "%Kargument %i value %qE exceeds "
1421 "maximum object size %E",
1422 exp, idx[i] + 1, args[i], maxobjsize);
1425 else if (TREE_CODE (args[i]) == SSA_NAME
1426 && get_size_range (args[i], argrange[i]))
1428 /* Verify that the argument's range is not negative (including
1429 upper bound of zero). */
1430 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1431 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1433 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1434 "%Kargument %i range [%E, %E] is negative",
1435 exp, idx[i] + 1,
1436 argrange[i][0], argrange[i][1]);
1438 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1440 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1441 "%Kargument %i range [%E, %E] exceeds "
1442 "maximum object size %E",
1443 exp, idx[i] + 1,
1444 argrange[i][0], argrange[i][1],
1445 maxobjsize);
1450 if (!argrange[0])
1451 return;
1453 /* For a two-argument alloc_size, validate the product of the two
1454 arguments if both of their values or ranges are known. */
1455 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1456 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1457 && !integer_onep (argrange[0][0])
1458 && !integer_onep (argrange[1][0]))
1460 /* Check for overflow in the product of a function decorated with
1461 attribute alloc_size (X, Y). */
1462 unsigned szprec = TYPE_PRECISION (size_type_node);
1463 wide_int x = wi::to_wide (argrange[0][0], szprec);
1464 wide_int y = wi::to_wide (argrange[1][0], szprec);
1466 bool vflow;
1467 wide_int prod = wi::umul (x, y, &vflow);
1469 if (vflow)
1470 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1471 "%Kproduct %<%E * %E%> of arguments %i and %i "
1472 "exceeds %<SIZE_MAX%>",
1473 exp, argrange[0][0], argrange[1][0],
1474 idx[0] + 1, idx[1] + 1);
1475 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1476 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1477 "%Kproduct %<%E * %E%> of arguments %i and %i "
1478 "exceeds maximum object size %E",
1479 exp, argrange[0][0], argrange[1][0],
1480 idx[0] + 1, idx[1] + 1,
1481 maxobjsize);
1483 if (warned)
1485 /* Print the full range of each of the two arguments to make
1486 it clear when it is, in fact, in a range and not constant. */
1487 if (argrange[0][0] != argrange [0][1])
1488 inform (loc, "argument %i in the range [%E, %E]",
1489 idx[0] + 1, argrange[0][0], argrange[0][1]);
1490 if (argrange[1][0] != argrange [1][1])
1491 inform (loc, "argument %i in the range [%E, %E]",
1492 idx[1] + 1, argrange[1][0], argrange[1][1]);
1496 if (warned)
1498 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1500 if (DECL_IS_BUILTIN (fn))
1501 inform (loc,
1502 "in a call to built-in allocation function %qD", fn);
1503 else
1504 inform (fnloc,
1505 "in a call to allocation function %qD declared here", fn);
1509 /* Issue an error if CALL_EXPR was flagged as requiring
1510 tall-call optimization. */
1512 static void
1513 maybe_complain_about_tail_call (tree call_expr, const char *reason)
1515 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1516 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1517 return;
1519 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1522 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1523 CALL_EXPR EXP.
1525 NUM_ACTUALS is the total number of parameters.
1527 N_NAMED_ARGS is the total number of named arguments.
1529 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1530 value, or null.
1532 FNDECL is the tree code for the target of this call (if known)
1534 ARGS_SO_FAR holds state needed by the target to know where to place
1535 the next argument.
1537 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1538 for arguments which are passed in registers.
1540 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1541 and may be modified by this routine.
1543 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1544 flags which may be modified by this routine.
1546 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1547 that requires allocation of stack space.
1549 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1550 the thunked-to function. */
1552 static void
1553 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1554 struct arg_data *args,
1555 struct args_size *args_size,
1556 int n_named_args ATTRIBUTE_UNUSED,
1557 tree exp, tree struct_value_addr_value,
1558 tree fndecl, tree fntype,
1559 cumulative_args_t args_so_far,
1560 int reg_parm_stack_space,
1561 rtx *old_stack_level, int *old_pending_adj,
1562 int *must_preallocate, int *ecf_flags,
1563 bool *may_tailcall, bool call_from_thunk_p)
1565 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1566 location_t loc = EXPR_LOCATION (exp);
1568 /* Count arg position in order args appear. */
1569 int argpos;
1571 int i;
1573 args_size->constant = 0;
1574 args_size->var = 0;
1576 bitmap_obstack_initialize (NULL);
1578 /* In this loop, we consider args in the order they are written.
1579 We fill up ARGS from the back. */
1581 i = num_actuals - 1;
1583 int j = i, ptr_arg = -1;
1584 call_expr_arg_iterator iter;
1585 tree arg;
1586 bitmap slots = NULL;
1588 if (struct_value_addr_value)
1590 args[j].tree_value = struct_value_addr_value;
1591 j--;
1593 /* If we pass structure address then we need to
1594 create bounds for it. Since created bounds is
1595 a call statement, we expand it right here to avoid
1596 fixing all other places where it may be expanded. */
1597 if (CALL_WITH_BOUNDS_P (exp))
1599 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1600 args[j].tree_value
1601 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1602 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1603 EXPAND_NORMAL, 0, false);
1604 args[j].pointer_arg = j + 1;
1605 j--;
1608 argpos = 0;
1609 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1611 tree argtype = TREE_TYPE (arg);
1613 /* Remember last param with pointer and associate it
1614 with following pointer bounds. */
1615 if (CALL_WITH_BOUNDS_P (exp)
1616 && chkp_type_has_pointer (argtype))
1618 if (slots)
1619 BITMAP_FREE (slots);
1620 ptr_arg = j;
1621 if (!BOUNDED_TYPE_P (argtype))
1623 slots = BITMAP_ALLOC (NULL);
1624 chkp_find_bound_slots (argtype, slots);
1627 else if (CALL_WITH_BOUNDS_P (exp)
1628 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1629 argpos < n_named_args))
1631 if (slots)
1632 BITMAP_FREE (slots);
1633 ptr_arg = j;
1635 else if (POINTER_BOUNDS_TYPE_P (argtype))
1637 /* We expect bounds in instrumented calls only.
1638 Otherwise it is a sign we lost flag due to some optimization
1639 and may emit call args incorrectly. */
1640 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1642 /* For structures look for the next available pointer. */
1643 if (ptr_arg != -1 && slots)
1645 unsigned bnd_no = bitmap_first_set_bit (slots);
1646 args[j].pointer_offset =
1647 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1649 bitmap_clear_bit (slots, bnd_no);
1651 /* Check we have no more pointers in the structure. */
1652 if (bitmap_empty_p (slots))
1653 BITMAP_FREE (slots);
1655 args[j].pointer_arg = ptr_arg;
1657 /* Check we covered all pointers in the previous
1658 non bounds arg. */
1659 if (!slots)
1660 ptr_arg = -1;
1662 else
1663 ptr_arg = -1;
1665 if (targetm.calls.split_complex_arg
1666 && argtype
1667 && TREE_CODE (argtype) == COMPLEX_TYPE
1668 && targetm.calls.split_complex_arg (argtype))
1670 tree subtype = TREE_TYPE (argtype);
1671 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1672 j--;
1673 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1675 else
1676 args[j].tree_value = arg;
1677 j--;
1678 argpos++;
1681 if (slots)
1682 BITMAP_FREE (slots);
1685 bitmap_obstack_release (NULL);
1687 /* Extract attribute alloc_size and if set, store the indices of
1688 the corresponding arguments in ALLOC_IDX, and then the actual
1689 argument(s) at those indices in ALLOC_ARGS. */
1690 int alloc_idx[2] = { -1, -1 };
1691 if (tree alloc_size
1692 = (fndecl ? lookup_attribute ("alloc_size",
1693 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1694 : NULL_TREE))
1696 tree args = TREE_VALUE (alloc_size);
1697 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1698 if (TREE_CHAIN (args))
1699 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1702 /* Array for up to the two attribute alloc_size arguments. */
1703 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1705 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1706 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1708 tree type = TREE_TYPE (args[i].tree_value);
1709 int unsignedp;
1710 machine_mode mode;
1712 /* Replace erroneous argument with constant zero. */
1713 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1714 args[i].tree_value = integer_zero_node, type = integer_type_node;
1716 /* If TYPE is a transparent union or record, pass things the way
1717 we would pass the first field of the union or record. We have
1718 already verified that the modes are the same. */
1719 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1720 && TYPE_TRANSPARENT_AGGR (type))
1721 type = TREE_TYPE (first_field (type));
1723 /* Decide where to pass this arg.
1725 args[i].reg is nonzero if all or part is passed in registers.
1727 args[i].partial is nonzero if part but not all is passed in registers,
1728 and the exact value says how many bytes are passed in registers.
1730 args[i].pass_on_stack is nonzero if the argument must at least be
1731 computed on the stack. It may then be loaded back into registers
1732 if args[i].reg is nonzero.
1734 These decisions are driven by the FUNCTION_... macros and must agree
1735 with those made by function.c. */
1737 /* See if this argument should be passed by invisible reference. */
1738 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1739 type, argpos < n_named_args))
1741 bool callee_copies;
1742 tree base = NULL_TREE;
1744 callee_copies
1745 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1746 type, argpos < n_named_args);
1748 /* If we're compiling a thunk, pass through invisible references
1749 instead of making a copy. */
1750 if (call_from_thunk_p
1751 || (callee_copies
1752 && !TREE_ADDRESSABLE (type)
1753 && (base = get_base_address (args[i].tree_value))
1754 && TREE_CODE (base) != SSA_NAME
1755 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1757 /* We may have turned the parameter value into an SSA name.
1758 Go back to the original parameter so we can take the
1759 address. */
1760 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1762 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1763 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1764 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1766 /* Argument setup code may have copied the value to register. We
1767 revert that optimization now because the tail call code must
1768 use the original location. */
1769 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1770 && !MEM_P (DECL_RTL (args[i].tree_value))
1771 && DECL_INCOMING_RTL (args[i].tree_value)
1772 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1773 set_decl_rtl (args[i].tree_value,
1774 DECL_INCOMING_RTL (args[i].tree_value));
1776 mark_addressable (args[i].tree_value);
1778 /* We can't use sibcalls if a callee-copied argument is
1779 stored in the current function's frame. */
1780 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1782 *may_tailcall = false;
1783 maybe_complain_about_tail_call (exp,
1784 "a callee-copied argument is"
1785 " stored in the current "
1786 " function's frame");
1789 args[i].tree_value = build_fold_addr_expr_loc (loc,
1790 args[i].tree_value);
1791 type = TREE_TYPE (args[i].tree_value);
1793 if (*ecf_flags & ECF_CONST)
1794 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1796 else
1798 /* We make a copy of the object and pass the address to the
1799 function being called. */
1800 rtx copy;
1802 if (!COMPLETE_TYPE_P (type)
1803 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1804 || (flag_stack_check == GENERIC_STACK_CHECK
1805 && compare_tree_int (TYPE_SIZE_UNIT (type),
1806 STACK_CHECK_MAX_VAR_SIZE) > 0))
1808 /* This is a variable-sized object. Make space on the stack
1809 for it. */
1810 rtx size_rtx = expr_size (args[i].tree_value);
1812 if (*old_stack_level == 0)
1814 emit_stack_save (SAVE_BLOCK, old_stack_level);
1815 *old_pending_adj = pending_stack_adjust;
1816 pending_stack_adjust = 0;
1819 /* We can pass TRUE as the 4th argument because we just
1820 saved the stack pointer and will restore it right after
1821 the call. */
1822 copy = allocate_dynamic_stack_space (size_rtx,
1823 TYPE_ALIGN (type),
1824 TYPE_ALIGN (type),
1825 true);
1826 copy = gen_rtx_MEM (BLKmode, copy);
1827 set_mem_attributes (copy, type, 1);
1829 else
1830 copy = assign_temp (type, 1, 0);
1832 store_expr (args[i].tree_value, copy, 0, false, false);
1834 /* Just change the const function to pure and then let
1835 the next test clear the pure based on
1836 callee_copies. */
1837 if (*ecf_flags & ECF_CONST)
1839 *ecf_flags &= ~ECF_CONST;
1840 *ecf_flags |= ECF_PURE;
1843 if (!callee_copies && *ecf_flags & ECF_PURE)
1844 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1846 args[i].tree_value
1847 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1848 type = TREE_TYPE (args[i].tree_value);
1849 *may_tailcall = false;
1850 maybe_complain_about_tail_call (exp,
1851 "argument must be passed"
1852 " by copying");
1856 unsignedp = TYPE_UNSIGNED (type);
1857 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1858 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1860 args[i].unsignedp = unsignedp;
1861 args[i].mode = mode;
1863 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1864 argpos < n_named_args);
1866 if (args[i].reg && CONST_INT_P (args[i].reg))
1868 args[i].special_slot = args[i].reg;
1869 args[i].reg = NULL;
1872 /* If this is a sibling call and the machine has register windows, the
1873 register window has to be unwinded before calling the routine, so
1874 arguments have to go into the incoming registers. */
1875 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1876 args[i].tail_call_reg
1877 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1878 argpos < n_named_args);
1879 else
1880 args[i].tail_call_reg = args[i].reg;
1882 if (args[i].reg)
1883 args[i].partial
1884 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1885 argpos < n_named_args);
1887 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1889 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1890 it means that we are to pass this arg in the register(s) designated
1891 by the PARALLEL, but also to pass it in the stack. */
1892 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1893 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1894 args[i].pass_on_stack = 1;
1896 /* If this is an addressable type, we must preallocate the stack
1897 since we must evaluate the object into its final location.
1899 If this is to be passed in both registers and the stack, it is simpler
1900 to preallocate. */
1901 if (TREE_ADDRESSABLE (type)
1902 || (args[i].pass_on_stack && args[i].reg != 0))
1903 *must_preallocate = 1;
1905 /* No stack allocation and padding for bounds. */
1906 if (POINTER_BOUNDS_P (args[i].tree_value))
1908 /* Compute the stack-size of this argument. */
1909 else if (args[i].reg == 0 || args[i].partial != 0
1910 || reg_parm_stack_space > 0
1911 || args[i].pass_on_stack)
1912 locate_and_pad_parm (mode, type,
1913 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1915 #else
1916 args[i].reg != 0,
1917 #endif
1918 reg_parm_stack_space,
1919 args[i].pass_on_stack ? 0 : args[i].partial,
1920 fndecl, args_size, &args[i].locate);
1921 #ifdef BLOCK_REG_PADDING
1922 else
1923 /* The argument is passed entirely in registers. See at which
1924 end it should be padded. */
1925 args[i].locate.where_pad =
1926 BLOCK_REG_PADDING (mode, type,
1927 int_size_in_bytes (type) <= UNITS_PER_WORD);
1928 #endif
1930 /* Update ARGS_SIZE, the total stack space for args so far. */
1932 args_size->constant += args[i].locate.size.constant;
1933 if (args[i].locate.size.var)
1934 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1936 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1937 have been used, etc. */
1939 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1940 type, argpos < n_named_args);
1942 /* Store argument values for functions decorated with attribute
1943 alloc_size. */
1944 if (argpos == alloc_idx[0])
1945 alloc_args[0] = args[i].tree_value;
1946 else if (argpos == alloc_idx[1])
1947 alloc_args[1] = args[i].tree_value;
1950 if (alloc_args[0])
1952 /* Check the arguments of functions decorated with attribute
1953 alloc_size. */
1954 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
1958 /* Update ARGS_SIZE to contain the total size for the argument block.
1959 Return the original constant component of the argument block's size.
1961 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1962 for arguments passed in registers. */
1964 static int
1965 compute_argument_block_size (int reg_parm_stack_space,
1966 struct args_size *args_size,
1967 tree fndecl ATTRIBUTE_UNUSED,
1968 tree fntype ATTRIBUTE_UNUSED,
1969 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1971 int unadjusted_args_size = args_size->constant;
1973 /* For accumulate outgoing args mode we don't need to align, since the frame
1974 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1975 backends from generating misaligned frame sizes. */
1976 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1977 preferred_stack_boundary = STACK_BOUNDARY;
1979 /* Compute the actual size of the argument block required. The variable
1980 and constant sizes must be combined, the size may have to be rounded,
1981 and there may be a minimum required size. */
1983 if (args_size->var)
1985 args_size->var = ARGS_SIZE_TREE (*args_size);
1986 args_size->constant = 0;
1988 preferred_stack_boundary /= BITS_PER_UNIT;
1989 if (preferred_stack_boundary > 1)
1991 /* We don't handle this case yet. To handle it correctly we have
1992 to add the delta, round and subtract the delta.
1993 Currently no machine description requires this support. */
1994 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1995 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1998 if (reg_parm_stack_space > 0)
2000 args_size->var
2001 = size_binop (MAX_EXPR, args_size->var,
2002 ssize_int (reg_parm_stack_space));
2004 /* The area corresponding to register parameters is not to count in
2005 the size of the block we need. So make the adjustment. */
2006 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2007 args_size->var
2008 = size_binop (MINUS_EXPR, args_size->var,
2009 ssize_int (reg_parm_stack_space));
2012 else
2014 preferred_stack_boundary /= BITS_PER_UNIT;
2015 if (preferred_stack_boundary < 1)
2016 preferred_stack_boundary = 1;
2017 args_size->constant = (((args_size->constant
2018 + stack_pointer_delta
2019 + preferred_stack_boundary - 1)
2020 / preferred_stack_boundary
2021 * preferred_stack_boundary)
2022 - stack_pointer_delta);
2024 args_size->constant = MAX (args_size->constant,
2025 reg_parm_stack_space);
2027 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2028 args_size->constant -= reg_parm_stack_space;
2030 return unadjusted_args_size;
2033 /* Precompute parameters as needed for a function call.
2035 FLAGS is mask of ECF_* constants.
2037 NUM_ACTUALS is the number of arguments.
2039 ARGS is an array containing information for each argument; this
2040 routine fills in the INITIAL_VALUE and VALUE fields for each
2041 precomputed argument. */
2043 static void
2044 precompute_arguments (int num_actuals, struct arg_data *args)
2046 int i;
2048 /* If this is a libcall, then precompute all arguments so that we do not
2049 get extraneous instructions emitted as part of the libcall sequence. */
2051 /* If we preallocated the stack space, and some arguments must be passed
2052 on the stack, then we must precompute any parameter which contains a
2053 function call which will store arguments on the stack.
2054 Otherwise, evaluating the parameter may clobber previous parameters
2055 which have already been stored into the stack. (we have code to avoid
2056 such case by saving the outgoing stack arguments, but it results in
2057 worse code) */
2058 if (!ACCUMULATE_OUTGOING_ARGS)
2059 return;
2061 for (i = 0; i < num_actuals; i++)
2063 tree type;
2064 machine_mode mode;
2066 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2067 continue;
2069 /* If this is an addressable type, we cannot pre-evaluate it. */
2070 type = TREE_TYPE (args[i].tree_value);
2071 gcc_assert (!TREE_ADDRESSABLE (type));
2073 args[i].initial_value = args[i].value
2074 = expand_normal (args[i].tree_value);
2076 mode = TYPE_MODE (type);
2077 if (mode != args[i].mode)
2079 int unsignedp = args[i].unsignedp;
2080 args[i].value
2081 = convert_modes (args[i].mode, mode,
2082 args[i].value, args[i].unsignedp);
2084 /* CSE will replace this only if it contains args[i].value
2085 pseudo, so convert it down to the declared mode using
2086 a SUBREG. */
2087 if (REG_P (args[i].value)
2088 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2089 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2091 args[i].initial_value
2092 = gen_lowpart_SUBREG (mode, args[i].value);
2093 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2094 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2100 /* Given the current state of MUST_PREALLOCATE and information about
2101 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2102 compute and return the final value for MUST_PREALLOCATE. */
2104 static int
2105 finalize_must_preallocate (int must_preallocate, int num_actuals,
2106 struct arg_data *args, struct args_size *args_size)
2108 /* See if we have or want to preallocate stack space.
2110 If we would have to push a partially-in-regs parm
2111 before other stack parms, preallocate stack space instead.
2113 If the size of some parm is not a multiple of the required stack
2114 alignment, we must preallocate.
2116 If the total size of arguments that would otherwise create a copy in
2117 a temporary (such as a CALL) is more than half the total argument list
2118 size, preallocation is faster.
2120 Another reason to preallocate is if we have a machine (like the m88k)
2121 where stack alignment is required to be maintained between every
2122 pair of insns, not just when the call is made. However, we assume here
2123 that such machines either do not have push insns (and hence preallocation
2124 would occur anyway) or the problem is taken care of with
2125 PUSH_ROUNDING. */
2127 if (! must_preallocate)
2129 int partial_seen = 0;
2130 int copy_to_evaluate_size = 0;
2131 int i;
2133 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2135 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2136 partial_seen = 1;
2137 else if (partial_seen && args[i].reg == 0)
2138 must_preallocate = 1;
2139 /* We preallocate in case there are bounds passed
2140 in the bounds table to have precomputed address
2141 for bounds association. */
2142 else if (POINTER_BOUNDS_P (args[i].tree_value)
2143 && !args[i].reg)
2144 must_preallocate = 1;
2146 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2147 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2148 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2149 || TREE_CODE (args[i].tree_value) == COND_EXPR
2150 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2151 copy_to_evaluate_size
2152 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2155 if (copy_to_evaluate_size * 2 >= args_size->constant
2156 && args_size->constant > 0)
2157 must_preallocate = 1;
2159 return must_preallocate;
2162 /* If we preallocated stack space, compute the address of each argument
2163 and store it into the ARGS array.
2165 We need not ensure it is a valid memory address here; it will be
2166 validized when it is used.
2168 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2170 static void
2171 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2173 if (argblock)
2175 rtx arg_reg = argblock;
2176 int i, arg_offset = 0;
2178 if (GET_CODE (argblock) == PLUS)
2179 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
2181 for (i = 0; i < num_actuals; i++)
2183 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2184 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2185 rtx addr;
2186 unsigned int align, boundary;
2187 unsigned int units_on_stack = 0;
2188 machine_mode partial_mode = VOIDmode;
2190 /* Skip this parm if it will not be passed on the stack. */
2191 if (! args[i].pass_on_stack
2192 && args[i].reg != 0
2193 && args[i].partial == 0)
2194 continue;
2196 /* Pointer Bounds are never passed on the stack. */
2197 if (POINTER_BOUNDS_P (args[i].tree_value))
2198 continue;
2200 if (CONST_INT_P (offset))
2201 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
2202 else
2203 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
2205 addr = plus_constant (Pmode, addr, arg_offset);
2207 if (args[i].partial != 0)
2209 /* Only part of the parameter is being passed on the stack.
2210 Generate a simple memory reference of the correct size. */
2211 units_on_stack = args[i].locate.size.constant;
2212 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
2213 MODE_INT, 1);
2214 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2215 set_mem_size (args[i].stack, units_on_stack);
2217 else
2219 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2220 set_mem_attributes (args[i].stack,
2221 TREE_TYPE (args[i].tree_value), 1);
2223 align = BITS_PER_UNIT;
2224 boundary = args[i].locate.boundary;
2225 if (args[i].locate.where_pad != PAD_DOWNWARD)
2226 align = boundary;
2227 else if (CONST_INT_P (offset))
2229 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
2230 align = least_bit_hwi (align);
2232 set_mem_align (args[i].stack, align);
2234 if (CONST_INT_P (slot_offset))
2235 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
2236 else
2237 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
2239 addr = plus_constant (Pmode, addr, arg_offset);
2241 if (args[i].partial != 0)
2243 /* Only part of the parameter is being passed on the stack.
2244 Generate a simple memory reference of the correct size.
2246 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2247 set_mem_size (args[i].stack_slot, units_on_stack);
2249 else
2251 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2252 set_mem_attributes (args[i].stack_slot,
2253 TREE_TYPE (args[i].tree_value), 1);
2255 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2257 /* Function incoming arguments may overlap with sibling call
2258 outgoing arguments and we cannot allow reordering of reads
2259 from function arguments with stores to outgoing arguments
2260 of sibling calls. */
2261 set_mem_alias_set (args[i].stack, 0);
2262 set_mem_alias_set (args[i].stack_slot, 0);
2267 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2268 in a call instruction.
2270 FNDECL is the tree node for the target function. For an indirect call
2271 FNDECL will be NULL_TREE.
2273 ADDR is the operand 0 of CALL_EXPR for this call. */
2275 static rtx
2276 rtx_for_function_call (tree fndecl, tree addr)
2278 rtx funexp;
2280 /* Get the function to call, in the form of RTL. */
2281 if (fndecl)
2283 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2284 TREE_USED (fndecl) = 1;
2286 /* Get a SYMBOL_REF rtx for the function address. */
2287 funexp = XEXP (DECL_RTL (fndecl), 0);
2289 else
2290 /* Generate an rtx (probably a pseudo-register) for the address. */
2292 push_temp_slots ();
2293 funexp = expand_normal (addr);
2294 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2296 return funexp;
2299 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2300 static struct
2302 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2303 or NULL_RTX if none has been scanned yet. */
2304 rtx_insn *scan_start;
2305 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2306 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2307 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2308 with fixed offset, or PC if this is with variable or unknown offset. */
2309 vec<rtx> cache;
2310 } internal_arg_pointer_exp_state;
2312 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2314 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2315 the tail call sequence, starting with first insn that hasn't been
2316 scanned yet, and note for each pseudo on the LHS whether it is based
2317 on crtl->args.internal_arg_pointer or not, and what offset from that
2318 that pointer it has. */
2320 static void
2321 internal_arg_pointer_based_exp_scan (void)
2323 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2325 if (scan_start == NULL_RTX)
2326 insn = get_insns ();
2327 else
2328 insn = NEXT_INSN (scan_start);
2330 while (insn)
2332 rtx set = single_set (insn);
2333 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2335 rtx val = NULL_RTX;
2336 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2337 /* Punt on pseudos set multiple times. */
2338 if (idx < internal_arg_pointer_exp_state.cache.length ()
2339 && (internal_arg_pointer_exp_state.cache[idx]
2340 != NULL_RTX))
2341 val = pc_rtx;
2342 else
2343 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2344 if (val != NULL_RTX)
2346 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2347 internal_arg_pointer_exp_state.cache
2348 .safe_grow_cleared (idx + 1);
2349 internal_arg_pointer_exp_state.cache[idx] = val;
2352 if (NEXT_INSN (insn) == NULL_RTX)
2353 scan_start = insn;
2354 insn = NEXT_INSN (insn);
2357 internal_arg_pointer_exp_state.scan_start = scan_start;
2360 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2361 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2362 it with fixed offset, or PC if this is with variable or unknown offset.
2363 TOPLEVEL is true if the function is invoked at the topmost level. */
2365 static rtx
2366 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2368 if (CONSTANT_P (rtl))
2369 return NULL_RTX;
2371 if (rtl == crtl->args.internal_arg_pointer)
2372 return const0_rtx;
2374 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2375 return NULL_RTX;
2377 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
2379 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2380 if (val == NULL_RTX || val == pc_rtx)
2381 return val;
2382 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
2385 /* When called at the topmost level, scan pseudo assignments in between the
2386 last scanned instruction in the tail call sequence and the latest insn
2387 in that sequence. */
2388 if (toplevel)
2389 internal_arg_pointer_based_exp_scan ();
2391 if (REG_P (rtl))
2393 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2394 if (idx < internal_arg_pointer_exp_state.cache.length ())
2395 return internal_arg_pointer_exp_state.cache[idx];
2397 return NULL_RTX;
2400 subrtx_iterator::array_type array;
2401 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2403 const_rtx x = *iter;
2404 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2405 return pc_rtx;
2406 if (MEM_P (x))
2407 iter.skip_subrtxes ();
2410 return NULL_RTX;
2413 /* Return true if and only if SIZE storage units (usually bytes)
2414 starting from address ADDR overlap with already clobbered argument
2415 area. This function is used to determine if we should give up a
2416 sibcall. */
2418 static bool
2419 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
2421 HOST_WIDE_INT i;
2422 rtx val;
2424 if (bitmap_empty_p (stored_args_map))
2425 return false;
2426 val = internal_arg_pointer_based_exp (addr, true);
2427 if (val == NULL_RTX)
2428 return false;
2429 else if (val == pc_rtx)
2430 return true;
2431 else
2432 i = INTVAL (val);
2434 if (STACK_GROWS_DOWNWARD)
2435 i -= crtl->args.pretend_args_size;
2436 else
2437 i += crtl->args.pretend_args_size;
2440 if (ARGS_GROW_DOWNWARD)
2441 i = -i - size;
2443 if (size > 0)
2445 unsigned HOST_WIDE_INT k;
2447 for (k = 0; k < size; k++)
2448 if (i + k < SBITMAP_SIZE (stored_args_map)
2449 && bitmap_bit_p (stored_args_map, i + k))
2450 return true;
2453 return false;
2456 /* Do the register loads required for any wholly-register parms or any
2457 parms which are passed both on the stack and in a register. Their
2458 expressions were already evaluated.
2460 Mark all register-parms as living through the call, putting these USE
2461 insns in the CALL_INSN_FUNCTION_USAGE field.
2463 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2464 checking, setting *SIBCALL_FAILURE if appropriate. */
2466 static void
2467 load_register_parameters (struct arg_data *args, int num_actuals,
2468 rtx *call_fusage, int flags, int is_sibcall,
2469 int *sibcall_failure)
2471 int i, j;
2473 for (i = 0; i < num_actuals; i++)
2475 rtx reg = ((flags & ECF_SIBCALL)
2476 ? args[i].tail_call_reg : args[i].reg);
2477 if (reg)
2479 int partial = args[i].partial;
2480 int nregs;
2481 int size = 0;
2482 rtx_insn *before_arg = get_last_insn ();
2483 /* Set non-negative if we must move a word at a time, even if
2484 just one word (e.g, partial == 4 && mode == DFmode). Set
2485 to -1 if we just use a normal move insn. This value can be
2486 zero if the argument is a zero size structure. */
2487 nregs = -1;
2488 if (GET_CODE (reg) == PARALLEL)
2490 else if (partial)
2492 gcc_assert (partial % UNITS_PER_WORD == 0);
2493 nregs = partial / UNITS_PER_WORD;
2495 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2497 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2498 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2500 else
2501 size = GET_MODE_SIZE (args[i].mode);
2503 /* Handle calls that pass values in multiple non-contiguous
2504 locations. The Irix 6 ABI has examples of this. */
2506 if (GET_CODE (reg) == PARALLEL)
2507 emit_group_move (reg, args[i].parallel_value);
2509 /* If simple case, just do move. If normal partial, store_one_arg
2510 has already loaded the register for us. In all other cases,
2511 load the register(s) from memory. */
2513 else if (nregs == -1)
2515 emit_move_insn (reg, args[i].value);
2516 #ifdef BLOCK_REG_PADDING
2517 /* Handle case where we have a value that needs shifting
2518 up to the msb. eg. a QImode value and we're padding
2519 upward on a BYTES_BIG_ENDIAN machine. */
2520 if (size < UNITS_PER_WORD
2521 && (args[i].locate.where_pad
2522 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2524 rtx x;
2525 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2527 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2528 report the whole reg as used. Strictly speaking, the
2529 call only uses SIZE bytes at the msb end, but it doesn't
2530 seem worth generating rtl to say that. */
2531 reg = gen_rtx_REG (word_mode, REGNO (reg));
2532 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2533 if (x != reg)
2534 emit_move_insn (reg, x);
2536 #endif
2539 /* If we have pre-computed the values to put in the registers in
2540 the case of non-aligned structures, copy them in now. */
2542 else if (args[i].n_aligned_regs != 0)
2543 for (j = 0; j < args[i].n_aligned_regs; j++)
2544 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2545 args[i].aligned_regs[j]);
2547 else if (partial == 0 || args[i].pass_on_stack)
2549 rtx mem = validize_mem (copy_rtx (args[i].value));
2551 /* Check for overlap with already clobbered argument area,
2552 providing that this has non-zero size. */
2553 if (is_sibcall
2554 && size != 0
2555 && (mem_overlaps_already_clobbered_arg_p
2556 (XEXP (args[i].value, 0), size)))
2557 *sibcall_failure = 1;
2559 if (size % UNITS_PER_WORD == 0
2560 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2561 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2562 else
2564 if (nregs > 1)
2565 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2566 args[i].mode);
2567 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2568 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2569 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2570 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2571 word_mode, word_mode, false,
2572 NULL);
2573 if (BYTES_BIG_ENDIAN)
2574 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2575 BITS_PER_WORD - bitsize, dest, 1);
2576 if (x != dest)
2577 emit_move_insn (dest, x);
2580 /* Handle a BLKmode that needs shifting. */
2581 if (nregs == 1 && size < UNITS_PER_WORD
2582 #ifdef BLOCK_REG_PADDING
2583 && args[i].locate.where_pad == PAD_DOWNWARD
2584 #else
2585 && BYTES_BIG_ENDIAN
2586 #endif
2589 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2590 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2591 enum tree_code dir = (BYTES_BIG_ENDIAN
2592 ? RSHIFT_EXPR : LSHIFT_EXPR);
2593 rtx x;
2595 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2596 if (x != dest)
2597 emit_move_insn (dest, x);
2601 /* When a parameter is a block, and perhaps in other cases, it is
2602 possible that it did a load from an argument slot that was
2603 already clobbered. */
2604 if (is_sibcall
2605 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2606 *sibcall_failure = 1;
2608 /* Handle calls that pass values in multiple non-contiguous
2609 locations. The Irix 6 ABI has examples of this. */
2610 if (GET_CODE (reg) == PARALLEL)
2611 use_group_regs (call_fusage, reg);
2612 else if (nregs == -1)
2613 use_reg_mode (call_fusage, reg,
2614 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2615 else if (nregs > 0)
2616 use_regs (call_fusage, REGNO (reg), nregs);
2621 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2622 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2623 bytes, then we would need to push some additional bytes to pad the
2624 arguments. So, we compute an adjust to the stack pointer for an
2625 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2626 bytes. Then, when the arguments are pushed the stack will be perfectly
2627 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2628 be popped after the call. Returns the adjustment. */
2630 static int
2631 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2632 struct args_size *args_size,
2633 unsigned int preferred_unit_stack_boundary)
2635 /* The number of bytes to pop so that the stack will be
2636 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2637 HOST_WIDE_INT adjustment;
2638 /* The alignment of the stack after the arguments are pushed, if we
2639 just pushed the arguments without adjust the stack here. */
2640 unsigned HOST_WIDE_INT unadjusted_alignment;
2642 unadjusted_alignment
2643 = ((stack_pointer_delta + unadjusted_args_size)
2644 % preferred_unit_stack_boundary);
2646 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2647 as possible -- leaving just enough left to cancel out the
2648 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2649 PENDING_STACK_ADJUST is non-negative, and congruent to
2650 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2652 /* Begin by trying to pop all the bytes. */
2653 unadjusted_alignment
2654 = (unadjusted_alignment
2655 - (pending_stack_adjust % preferred_unit_stack_boundary));
2656 adjustment = pending_stack_adjust;
2657 /* Push enough additional bytes that the stack will be aligned
2658 after the arguments are pushed. */
2659 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2660 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2662 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2663 bytes after the call. The right number is the entire
2664 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2665 by the arguments in the first place. */
2666 args_size->constant
2667 = pending_stack_adjust - adjustment + unadjusted_args_size;
2669 return adjustment;
2672 /* Scan X expression if it does not dereference any argument slots
2673 we already clobbered by tail call arguments (as noted in stored_args_map
2674 bitmap).
2675 Return nonzero if X expression dereferences such argument slots,
2676 zero otherwise. */
2678 static int
2679 check_sibcall_argument_overlap_1 (rtx x)
2681 RTX_CODE code;
2682 int i, j;
2683 const char *fmt;
2685 if (x == NULL_RTX)
2686 return 0;
2688 code = GET_CODE (x);
2690 /* We need not check the operands of the CALL expression itself. */
2691 if (code == CALL)
2692 return 0;
2694 if (code == MEM)
2695 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2696 GET_MODE_SIZE (GET_MODE (x)));
2698 /* Scan all subexpressions. */
2699 fmt = GET_RTX_FORMAT (code);
2700 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2702 if (*fmt == 'e')
2704 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2705 return 1;
2707 else if (*fmt == 'E')
2709 for (j = 0; j < XVECLEN (x, i); j++)
2710 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2711 return 1;
2714 return 0;
2717 /* Scan sequence after INSN if it does not dereference any argument slots
2718 we already clobbered by tail call arguments (as noted in stored_args_map
2719 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2720 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2721 should be 0). Return nonzero if sequence after INSN dereferences such argument
2722 slots, zero otherwise. */
2724 static int
2725 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2726 int mark_stored_args_map)
2728 int low, high;
2730 if (insn == NULL_RTX)
2731 insn = get_insns ();
2732 else
2733 insn = NEXT_INSN (insn);
2735 for (; insn; insn = NEXT_INSN (insn))
2736 if (INSN_P (insn)
2737 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2738 break;
2740 if (mark_stored_args_map)
2742 if (ARGS_GROW_DOWNWARD)
2743 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2744 else
2745 low = arg->locate.slot_offset.constant;
2747 for (high = low + arg->locate.size.constant; low < high; low++)
2748 bitmap_set_bit (stored_args_map, low);
2750 return insn != NULL_RTX;
2753 /* Given that a function returns a value of mode MODE at the most
2754 significant end of hard register VALUE, shift VALUE left or right
2755 as specified by LEFT_P. Return true if some action was needed. */
2757 bool
2758 shift_return_value (machine_mode mode, bool left_p, rtx value)
2760 HOST_WIDE_INT shift;
2762 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2763 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2764 if (shift == 0)
2765 return false;
2767 /* Use ashr rather than lshr for right shifts. This is for the benefit
2768 of the MIPS port, which requires SImode values to be sign-extended
2769 when stored in 64-bit registers. */
2770 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2771 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2772 gcc_unreachable ();
2773 return true;
2776 /* If X is a likely-spilled register value, copy it to a pseudo
2777 register and return that register. Return X otherwise. */
2779 static rtx
2780 avoid_likely_spilled_reg (rtx x)
2782 rtx new_rtx;
2784 if (REG_P (x)
2785 && HARD_REGISTER_P (x)
2786 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2788 /* Make sure that we generate a REG rather than a CONCAT.
2789 Moves into CONCATs can need nontrivial instructions,
2790 and the whole point of this function is to avoid
2791 using the hard register directly in such a situation. */
2792 generating_concat_p = 0;
2793 new_rtx = gen_reg_rtx (GET_MODE (x));
2794 generating_concat_p = 1;
2795 emit_move_insn (new_rtx, x);
2796 return new_rtx;
2798 return x;
2801 /* Helper function for expand_call.
2802 Return false is EXP is not implementable as a sibling call. */
2804 static bool
2805 can_implement_as_sibling_call_p (tree exp,
2806 rtx structure_value_addr,
2807 tree funtype,
2808 int reg_parm_stack_space ATTRIBUTE_UNUSED,
2809 tree fndecl,
2810 int flags,
2811 tree addr,
2812 const args_size &args_size)
2814 if (!targetm.have_sibcall_epilogue ())
2816 maybe_complain_about_tail_call
2817 (exp,
2818 "machine description does not have"
2819 " a sibcall_epilogue instruction pattern");
2820 return false;
2823 /* Doing sibling call optimization needs some work, since
2824 structure_value_addr can be allocated on the stack.
2825 It does not seem worth the effort since few optimizable
2826 sibling calls will return a structure. */
2827 if (structure_value_addr != NULL_RTX)
2829 maybe_complain_about_tail_call (exp, "callee returns a structure");
2830 return false;
2833 #ifdef REG_PARM_STACK_SPACE
2834 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2835 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2836 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
2837 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
2839 maybe_complain_about_tail_call (exp,
2840 "inconsistent size of stack space"
2841 " allocated for arguments which are"
2842 " passed in registers");
2843 return false;
2845 #endif
2847 /* Check whether the target is able to optimize the call
2848 into a sibcall. */
2849 if (!targetm.function_ok_for_sibcall (fndecl, exp))
2851 maybe_complain_about_tail_call (exp,
2852 "target is not able to optimize the"
2853 " call into a sibling call");
2854 return false;
2857 /* Functions that do not return exactly once may not be sibcall
2858 optimized. */
2859 if (flags & ECF_RETURNS_TWICE)
2861 maybe_complain_about_tail_call (exp, "callee returns twice");
2862 return false;
2864 if (flags & ECF_NORETURN)
2866 maybe_complain_about_tail_call (exp, "callee does not return");
2867 return false;
2870 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
2872 maybe_complain_about_tail_call (exp, "volatile function type");
2873 return false;
2876 /* If the called function is nested in the current one, it might access
2877 some of the caller's arguments, but could clobber them beforehand if
2878 the argument areas are shared. */
2879 if (fndecl && decl_function_context (fndecl) == current_function_decl)
2881 maybe_complain_about_tail_call (exp, "nested function");
2882 return false;
2885 /* If this function requires more stack slots than the current
2886 function, we cannot change it into a sibling call.
2887 crtl->args.pretend_args_size is not part of the
2888 stack allocated by our caller. */
2889 if (args_size.constant > (crtl->args.size - crtl->args.pretend_args_size))
2891 maybe_complain_about_tail_call (exp,
2892 "callee required more stack slots"
2893 " than the caller");
2894 return false;
2897 /* If the callee pops its own arguments, then it must pop exactly
2898 the same number of arguments as the current function. */
2899 if (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2900 != targetm.calls.return_pops_args (current_function_decl,
2901 TREE_TYPE (current_function_decl),
2902 crtl->args.size))
2904 maybe_complain_about_tail_call (exp,
2905 "inconsistent number of"
2906 " popped arguments");
2907 return false;
2910 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
2912 maybe_complain_about_tail_call (exp, "frontend does not support"
2913 " sibling call");
2914 return false;
2917 /* All checks passed. */
2918 return true;
2921 /* Generate all the code for a CALL_EXPR exp
2922 and return an rtx for its value.
2923 Store the value in TARGET (specified as an rtx) if convenient.
2924 If the value is stored in TARGET then TARGET is returned.
2925 If IGNORE is nonzero, then we ignore the value of the function call. */
2928 expand_call (tree exp, rtx target, int ignore)
2930 /* Nonzero if we are currently expanding a call. */
2931 static int currently_expanding_call = 0;
2933 /* RTX for the function to be called. */
2934 rtx funexp;
2935 /* Sequence of insns to perform a normal "call". */
2936 rtx_insn *normal_call_insns = NULL;
2937 /* Sequence of insns to perform a tail "call". */
2938 rtx_insn *tail_call_insns = NULL;
2939 /* Data type of the function. */
2940 tree funtype;
2941 tree type_arg_types;
2942 tree rettype;
2943 /* Declaration of the function being called,
2944 or 0 if the function is computed (not known by name). */
2945 tree fndecl = 0;
2946 /* The type of the function being called. */
2947 tree fntype;
2948 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2949 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
2950 int pass;
2952 /* Register in which non-BLKmode value will be returned,
2953 or 0 if no value or if value is BLKmode. */
2954 rtx valreg;
2955 /* Register(s) in which bounds are returned. */
2956 rtx valbnd = NULL;
2957 /* Address where we should return a BLKmode value;
2958 0 if value not BLKmode. */
2959 rtx structure_value_addr = 0;
2960 /* Nonzero if that address is being passed by treating it as
2961 an extra, implicit first parameter. Otherwise,
2962 it is passed by being copied directly into struct_value_rtx. */
2963 int structure_value_addr_parm = 0;
2964 /* Holds the value of implicit argument for the struct value. */
2965 tree structure_value_addr_value = NULL_TREE;
2966 /* Size of aggregate value wanted, or zero if none wanted
2967 or if we are using the non-reentrant PCC calling convention
2968 or expecting the value in registers. */
2969 HOST_WIDE_INT struct_value_size = 0;
2970 /* Nonzero if called function returns an aggregate in memory PCC style,
2971 by returning the address of where to find it. */
2972 int pcc_struct_value = 0;
2973 rtx struct_value = 0;
2975 /* Number of actual parameters in this call, including struct value addr. */
2976 int num_actuals;
2977 /* Number of named args. Args after this are anonymous ones
2978 and they must all go on the stack. */
2979 int n_named_args;
2980 /* Number of complex actual arguments that need to be split. */
2981 int num_complex_actuals = 0;
2983 /* Vector of information about each argument.
2984 Arguments are numbered in the order they will be pushed,
2985 not the order they are written. */
2986 struct arg_data *args;
2988 /* Total size in bytes of all the stack-parms scanned so far. */
2989 struct args_size args_size;
2990 struct args_size adjusted_args_size;
2991 /* Size of arguments before any adjustments (such as rounding). */
2992 int unadjusted_args_size;
2993 /* Data on reg parms scanned so far. */
2994 CUMULATIVE_ARGS args_so_far_v;
2995 cumulative_args_t args_so_far;
2996 /* Nonzero if a reg parm has been scanned. */
2997 int reg_parm_seen;
2998 /* Nonzero if this is an indirect function call. */
3000 /* Nonzero if we must avoid push-insns in the args for this call.
3001 If stack space is allocated for register parameters, but not by the
3002 caller, then it is preallocated in the fixed part of the stack frame.
3003 So the entire argument block must then be preallocated (i.e., we
3004 ignore PUSH_ROUNDING in that case). */
3006 int must_preallocate = !PUSH_ARGS;
3008 /* Size of the stack reserved for parameter registers. */
3009 int reg_parm_stack_space = 0;
3011 /* Address of space preallocated for stack parms
3012 (on machines that lack push insns), or 0 if space not preallocated. */
3013 rtx argblock = 0;
3015 /* Mask of ECF_ and ERF_ flags. */
3016 int flags = 0;
3017 int return_flags = 0;
3018 #ifdef REG_PARM_STACK_SPACE
3019 /* Define the boundary of the register parm stack space that needs to be
3020 saved, if any. */
3021 int low_to_save, high_to_save;
3022 rtx save_area = 0; /* Place that it is saved */
3023 #endif
3025 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3026 char *initial_stack_usage_map = stack_usage_map;
3027 char *stack_usage_map_buf = NULL;
3029 int old_stack_allocated;
3031 /* State variables to track stack modifications. */
3032 rtx old_stack_level = 0;
3033 int old_stack_arg_under_construction = 0;
3034 int old_pending_adj = 0;
3035 int old_inhibit_defer_pop = inhibit_defer_pop;
3037 /* Some stack pointer alterations we make are performed via
3038 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3039 which we then also need to save/restore along the way. */
3040 int old_stack_pointer_delta = 0;
3042 rtx call_fusage;
3043 tree addr = CALL_EXPR_FN (exp);
3044 int i;
3045 /* The alignment of the stack, in bits. */
3046 unsigned HOST_WIDE_INT preferred_stack_boundary;
3047 /* The alignment of the stack, in bytes. */
3048 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3049 /* The static chain value to use for this call. */
3050 rtx static_chain_value;
3051 /* See if this is "nothrow" function call. */
3052 if (TREE_NOTHROW (exp))
3053 flags |= ECF_NOTHROW;
3055 /* See if we can find a DECL-node for the actual function, and get the
3056 function attributes (flags) from the function decl or type node. */
3057 fndecl = get_callee_fndecl (exp);
3058 if (fndecl)
3060 fntype = TREE_TYPE (fndecl);
3061 flags |= flags_from_decl_or_type (fndecl);
3062 return_flags |= decl_return_flags (fndecl);
3064 else
3066 fntype = TREE_TYPE (TREE_TYPE (addr));
3067 flags |= flags_from_decl_or_type (fntype);
3068 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3069 flags |= ECF_BY_DESCRIPTOR;
3071 rettype = TREE_TYPE (exp);
3073 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3075 /* Warn if this value is an aggregate type,
3076 regardless of which calling convention we are using for it. */
3077 if (AGGREGATE_TYPE_P (rettype))
3078 warning (OPT_Waggregate_return, "function call has aggregate value");
3080 /* If the result of a non looping pure or const function call is
3081 ignored (or void), and none of its arguments are volatile, we can
3082 avoid expanding the call and just evaluate the arguments for
3083 side-effects. */
3084 if ((flags & (ECF_CONST | ECF_PURE))
3085 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3086 && (ignore || target == const0_rtx
3087 || TYPE_MODE (rettype) == VOIDmode))
3089 bool volatilep = false;
3090 tree arg;
3091 call_expr_arg_iterator iter;
3093 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3094 if (TREE_THIS_VOLATILE (arg))
3096 volatilep = true;
3097 break;
3100 if (! volatilep)
3102 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3103 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3104 return const0_rtx;
3108 #ifdef REG_PARM_STACK_SPACE
3109 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3110 #endif
3112 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3113 && reg_parm_stack_space > 0 && PUSH_ARGS)
3114 must_preallocate = 1;
3116 /* Set up a place to return a structure. */
3118 /* Cater to broken compilers. */
3119 if (aggregate_value_p (exp, fntype))
3121 /* This call returns a big structure. */
3122 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3124 #ifdef PCC_STATIC_STRUCT_RETURN
3126 pcc_struct_value = 1;
3128 #else /* not PCC_STATIC_STRUCT_RETURN */
3130 struct_value_size = int_size_in_bytes (rettype);
3132 /* Even if it is semantically safe to use the target as the return
3133 slot, it may be not sufficiently aligned for the return type. */
3134 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3135 && target
3136 && MEM_P (target)
3137 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3138 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
3139 MEM_ALIGN (target))))
3140 structure_value_addr = XEXP (target, 0);
3141 else
3143 /* For variable-sized objects, we must be called with a target
3144 specified. If we were to allocate space on the stack here,
3145 we would have no way of knowing when to free it. */
3146 rtx d = assign_temp (rettype, 1, 1);
3147 structure_value_addr = XEXP (d, 0);
3148 target = 0;
3151 #endif /* not PCC_STATIC_STRUCT_RETURN */
3154 /* Figure out the amount to which the stack should be aligned. */
3155 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3156 if (fndecl)
3158 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3159 /* Without automatic stack alignment, we can't increase preferred
3160 stack boundary. With automatic stack alignment, it is
3161 unnecessary since unless we can guarantee that all callers will
3162 align the outgoing stack properly, callee has to align its
3163 stack anyway. */
3164 if (i
3165 && i->preferred_incoming_stack_boundary
3166 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3167 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3170 /* Operand 0 is a pointer-to-function; get the type of the function. */
3171 funtype = TREE_TYPE (addr);
3172 gcc_assert (POINTER_TYPE_P (funtype));
3173 funtype = TREE_TYPE (funtype);
3175 /* Count whether there are actual complex arguments that need to be split
3176 into their real and imaginary parts. Munge the type_arg_types
3177 appropriately here as well. */
3178 if (targetm.calls.split_complex_arg)
3180 call_expr_arg_iterator iter;
3181 tree arg;
3182 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3184 tree type = TREE_TYPE (arg);
3185 if (type && TREE_CODE (type) == COMPLEX_TYPE
3186 && targetm.calls.split_complex_arg (type))
3187 num_complex_actuals++;
3189 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3191 else
3192 type_arg_types = TYPE_ARG_TYPES (funtype);
3194 if (flags & ECF_MAY_BE_ALLOCA)
3195 cfun->calls_alloca = 1;
3197 /* If struct_value_rtx is 0, it means pass the address
3198 as if it were an extra parameter. Put the argument expression
3199 in structure_value_addr_value. */
3200 if (structure_value_addr && struct_value == 0)
3202 /* If structure_value_addr is a REG other than
3203 virtual_outgoing_args_rtx, we can use always use it. If it
3204 is not a REG, we must always copy it into a register.
3205 If it is virtual_outgoing_args_rtx, we must copy it to another
3206 register in some cases. */
3207 rtx temp = (!REG_P (structure_value_addr)
3208 || (ACCUMULATE_OUTGOING_ARGS
3209 && stack_arg_under_construction
3210 && structure_value_addr == virtual_outgoing_args_rtx)
3211 ? copy_addr_to_reg (convert_memory_address
3212 (Pmode, structure_value_addr))
3213 : structure_value_addr);
3215 structure_value_addr_value =
3216 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3217 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3220 /* Count the arguments and set NUM_ACTUALS. */
3221 num_actuals =
3222 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3224 /* Compute number of named args.
3225 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3227 if (type_arg_types != 0)
3228 n_named_args
3229 = (list_length (type_arg_types)
3230 /* Count the struct value address, if it is passed as a parm. */
3231 + structure_value_addr_parm);
3232 else
3233 /* If we know nothing, treat all args as named. */
3234 n_named_args = num_actuals;
3236 /* Start updating where the next arg would go.
3238 On some machines (such as the PA) indirect calls have a different
3239 calling convention than normal calls. The fourth argument in
3240 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3241 or not. */
3242 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3243 args_so_far = pack_cumulative_args (&args_so_far_v);
3245 /* Now possibly adjust the number of named args.
3246 Normally, don't include the last named arg if anonymous args follow.
3247 We do include the last named arg if
3248 targetm.calls.strict_argument_naming() returns nonzero.
3249 (If no anonymous args follow, the result of list_length is actually
3250 one too large. This is harmless.)
3252 If targetm.calls.pretend_outgoing_varargs_named() returns
3253 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3254 this machine will be able to place unnamed args that were passed
3255 in registers into the stack. So treat all args as named. This
3256 allows the insns emitting for a specific argument list to be
3257 independent of the function declaration.
3259 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3260 we do not have any reliable way to pass unnamed args in
3261 registers, so we must force them into memory. */
3263 if (type_arg_types != 0
3264 && targetm.calls.strict_argument_naming (args_so_far))
3266 else if (type_arg_types != 0
3267 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3268 /* Don't include the last named arg. */
3269 --n_named_args;
3270 else
3271 /* Treat all args as named. */
3272 n_named_args = num_actuals;
3274 /* Make a vector to hold all the information about each arg. */
3275 args = XCNEWVEC (struct arg_data, num_actuals);
3277 /* Build up entries in the ARGS array, compute the size of the
3278 arguments into ARGS_SIZE, etc. */
3279 initialize_argument_information (num_actuals, args, &args_size,
3280 n_named_args, exp,
3281 structure_value_addr_value, fndecl, fntype,
3282 args_so_far, reg_parm_stack_space,
3283 &old_stack_level, &old_pending_adj,
3284 &must_preallocate, &flags,
3285 &try_tail_call, CALL_FROM_THUNK_P (exp));
3287 if (args_size.var)
3288 must_preallocate = 1;
3290 /* Now make final decision about preallocating stack space. */
3291 must_preallocate = finalize_must_preallocate (must_preallocate,
3292 num_actuals, args,
3293 &args_size);
3295 /* If the structure value address will reference the stack pointer, we
3296 must stabilize it. We don't need to do this if we know that we are
3297 not going to adjust the stack pointer in processing this call. */
3299 if (structure_value_addr
3300 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3301 || reg_mentioned_p (virtual_outgoing_args_rtx,
3302 structure_value_addr))
3303 && (args_size.var
3304 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
3305 structure_value_addr = copy_to_reg (structure_value_addr);
3307 /* Tail calls can make things harder to debug, and we've traditionally
3308 pushed these optimizations into -O2. Don't try if we're already
3309 expanding a call, as that means we're an argument. Don't try if
3310 there's cleanups, as we know there's code to follow the call. */
3312 if (currently_expanding_call++ != 0
3313 || !flag_optimize_sibling_calls
3314 || args_size.var
3315 || dbg_cnt (tail_call) == false)
3316 try_tail_call = 0;
3318 /* If the user has marked the function as requiring tail-call
3319 optimization, attempt it. */
3320 if (must_tail_call)
3321 try_tail_call = 1;
3323 /* Rest of purposes for tail call optimizations to fail. */
3324 if (try_tail_call)
3325 try_tail_call = can_implement_as_sibling_call_p (exp,
3326 structure_value_addr,
3327 funtype,
3328 reg_parm_stack_space,
3329 fndecl,
3330 flags, addr, args_size);
3332 /* Check if caller and callee disagree in promotion of function
3333 return value. */
3334 if (try_tail_call)
3336 machine_mode caller_mode, caller_promoted_mode;
3337 machine_mode callee_mode, callee_promoted_mode;
3338 int caller_unsignedp, callee_unsignedp;
3339 tree caller_res = DECL_RESULT (current_function_decl);
3341 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3342 caller_mode = DECL_MODE (caller_res);
3343 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3344 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3345 caller_promoted_mode
3346 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3347 &caller_unsignedp,
3348 TREE_TYPE (current_function_decl), 1);
3349 callee_promoted_mode
3350 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3351 &callee_unsignedp,
3352 funtype, 1);
3353 if (caller_mode != VOIDmode
3354 && (caller_promoted_mode != callee_promoted_mode
3355 || ((caller_mode != caller_promoted_mode
3356 || callee_mode != callee_promoted_mode)
3357 && (caller_unsignedp != callee_unsignedp
3358 || partial_subreg_p (caller_mode, callee_mode)))))
3360 try_tail_call = 0;
3361 maybe_complain_about_tail_call (exp,
3362 "caller and callee disagree in"
3363 " promotion of function"
3364 " return value");
3368 /* Ensure current function's preferred stack boundary is at least
3369 what we need. Stack alignment may also increase preferred stack
3370 boundary. */
3371 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3372 crtl->preferred_stack_boundary = preferred_stack_boundary;
3373 else
3374 preferred_stack_boundary = crtl->preferred_stack_boundary;
3376 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3378 /* We want to make two insn chains; one for a sibling call, the other
3379 for a normal call. We will select one of the two chains after
3380 initial RTL generation is complete. */
3381 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3383 int sibcall_failure = 0;
3384 /* We want to emit any pending stack adjustments before the tail
3385 recursion "call". That way we know any adjustment after the tail
3386 recursion call can be ignored if we indeed use the tail
3387 call expansion. */
3388 saved_pending_stack_adjust save;
3389 rtx_insn *insns, *before_call, *after_args;
3390 rtx next_arg_reg;
3392 if (pass == 0)
3394 /* State variables we need to save and restore between
3395 iterations. */
3396 save_pending_stack_adjust (&save);
3398 if (pass)
3399 flags &= ~ECF_SIBCALL;
3400 else
3401 flags |= ECF_SIBCALL;
3403 /* Other state variables that we must reinitialize each time
3404 through the loop (that are not initialized by the loop itself). */
3405 argblock = 0;
3406 call_fusage = 0;
3408 /* Start a new sequence for the normal call case.
3410 From this point on, if the sibling call fails, we want to set
3411 sibcall_failure instead of continuing the loop. */
3412 start_sequence ();
3414 /* Don't let pending stack adjusts add up to too much.
3415 Also, do all pending adjustments now if there is any chance
3416 this might be a call to alloca or if we are expanding a sibling
3417 call sequence.
3418 Also do the adjustments before a throwing call, otherwise
3419 exception handling can fail; PR 19225. */
3420 if (pending_stack_adjust >= 32
3421 || (pending_stack_adjust > 0
3422 && (flags & ECF_MAY_BE_ALLOCA))
3423 || (pending_stack_adjust > 0
3424 && flag_exceptions && !(flags & ECF_NOTHROW))
3425 || pass == 0)
3426 do_pending_stack_adjust ();
3428 /* Precompute any arguments as needed. */
3429 if (pass)
3430 precompute_arguments (num_actuals, args);
3432 /* Now we are about to start emitting insns that can be deleted
3433 if a libcall is deleted. */
3434 if (pass && (flags & ECF_MALLOC))
3435 start_sequence ();
3437 if (pass == 0
3438 && crtl->stack_protect_guard
3439 && targetm.stack_protect_runtime_enabled_p ())
3440 stack_protect_epilogue ();
3442 adjusted_args_size = args_size;
3443 /* Compute the actual size of the argument block required. The variable
3444 and constant sizes must be combined, the size may have to be rounded,
3445 and there may be a minimum required size. When generating a sibcall
3446 pattern, do not round up, since we'll be re-using whatever space our
3447 caller provided. */
3448 unadjusted_args_size
3449 = compute_argument_block_size (reg_parm_stack_space,
3450 &adjusted_args_size,
3451 fndecl, fntype,
3452 (pass == 0 ? 0
3453 : preferred_stack_boundary));
3455 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3457 /* The argument block when performing a sibling call is the
3458 incoming argument block. */
3459 if (pass == 0)
3461 argblock = crtl->args.internal_arg_pointer;
3462 if (STACK_GROWS_DOWNWARD)
3463 argblock
3464 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3465 else
3466 argblock
3467 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3469 stored_args_map = sbitmap_alloc (args_size.constant);
3470 bitmap_clear (stored_args_map);
3473 /* If we have no actual push instructions, or shouldn't use them,
3474 make space for all args right now. */
3475 else if (adjusted_args_size.var != 0)
3477 if (old_stack_level == 0)
3479 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3480 old_stack_pointer_delta = stack_pointer_delta;
3481 old_pending_adj = pending_stack_adjust;
3482 pending_stack_adjust = 0;
3483 /* stack_arg_under_construction says whether a stack arg is
3484 being constructed at the old stack level. Pushing the stack
3485 gets a clean outgoing argument block. */
3486 old_stack_arg_under_construction = stack_arg_under_construction;
3487 stack_arg_under_construction = 0;
3489 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3490 if (flag_stack_usage_info)
3491 current_function_has_unbounded_dynamic_stack_size = 1;
3493 else
3495 /* Note that we must go through the motions of allocating an argument
3496 block even if the size is zero because we may be storing args
3497 in the area reserved for register arguments, which may be part of
3498 the stack frame. */
3500 int needed = adjusted_args_size.constant;
3502 /* Store the maximum argument space used. It will be pushed by
3503 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3504 checking). */
3506 if (needed > crtl->outgoing_args_size)
3507 crtl->outgoing_args_size = needed;
3509 if (must_preallocate)
3511 if (ACCUMULATE_OUTGOING_ARGS)
3513 /* Since the stack pointer will never be pushed, it is
3514 possible for the evaluation of a parm to clobber
3515 something we have already written to the stack.
3516 Since most function calls on RISC machines do not use
3517 the stack, this is uncommon, but must work correctly.
3519 Therefore, we save any area of the stack that was already
3520 written and that we are using. Here we set up to do this
3521 by making a new stack usage map from the old one. The
3522 actual save will be done by store_one_arg.
3524 Another approach might be to try to reorder the argument
3525 evaluations to avoid this conflicting stack usage. */
3527 /* Since we will be writing into the entire argument area,
3528 the map must be allocated for its entire size, not just
3529 the part that is the responsibility of the caller. */
3530 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3531 needed += reg_parm_stack_space;
3533 if (ARGS_GROW_DOWNWARD)
3534 highest_outgoing_arg_in_use
3535 = MAX (initial_highest_arg_in_use, needed + 1);
3536 else
3537 highest_outgoing_arg_in_use
3538 = MAX (initial_highest_arg_in_use, needed);
3540 free (stack_usage_map_buf);
3541 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3542 stack_usage_map = stack_usage_map_buf;
3544 if (initial_highest_arg_in_use)
3545 memcpy (stack_usage_map, initial_stack_usage_map,
3546 initial_highest_arg_in_use);
3548 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3549 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3550 (highest_outgoing_arg_in_use
3551 - initial_highest_arg_in_use));
3552 needed = 0;
3554 /* The address of the outgoing argument list must not be
3555 copied to a register here, because argblock would be left
3556 pointing to the wrong place after the call to
3557 allocate_dynamic_stack_space below. */
3559 argblock = virtual_outgoing_args_rtx;
3561 else
3563 if (inhibit_defer_pop == 0)
3565 /* Try to reuse some or all of the pending_stack_adjust
3566 to get this space. */
3567 needed
3568 = (combine_pending_stack_adjustment_and_call
3569 (unadjusted_args_size,
3570 &adjusted_args_size,
3571 preferred_unit_stack_boundary));
3573 /* combine_pending_stack_adjustment_and_call computes
3574 an adjustment before the arguments are allocated.
3575 Account for them and see whether or not the stack
3576 needs to go up or down. */
3577 needed = unadjusted_args_size - needed;
3579 if (needed < 0)
3581 /* We're releasing stack space. */
3582 /* ??? We can avoid any adjustment at all if we're
3583 already aligned. FIXME. */
3584 pending_stack_adjust = -needed;
3585 do_pending_stack_adjust ();
3586 needed = 0;
3588 else
3589 /* We need to allocate space. We'll do that in
3590 push_block below. */
3591 pending_stack_adjust = 0;
3594 /* Special case this because overhead of `push_block' in
3595 this case is non-trivial. */
3596 if (needed == 0)
3597 argblock = virtual_outgoing_args_rtx;
3598 else
3600 argblock = push_block (GEN_INT (needed), 0, 0);
3601 if (ARGS_GROW_DOWNWARD)
3602 argblock = plus_constant (Pmode, argblock, needed);
3605 /* We only really need to call `copy_to_reg' in the case
3606 where push insns are going to be used to pass ARGBLOCK
3607 to a function call in ARGS. In that case, the stack
3608 pointer changes value from the allocation point to the
3609 call point, and hence the value of
3610 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3611 as well always do it. */
3612 argblock = copy_to_reg (argblock);
3617 if (ACCUMULATE_OUTGOING_ARGS)
3619 /* The save/restore code in store_one_arg handles all
3620 cases except one: a constructor call (including a C
3621 function returning a BLKmode struct) to initialize
3622 an argument. */
3623 if (stack_arg_under_construction)
3625 rtx push_size
3626 = GEN_INT (adjusted_args_size.constant
3627 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3628 : TREE_TYPE (fndecl))) ? 0
3629 : reg_parm_stack_space));
3630 if (old_stack_level == 0)
3632 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3633 old_stack_pointer_delta = stack_pointer_delta;
3634 old_pending_adj = pending_stack_adjust;
3635 pending_stack_adjust = 0;
3636 /* stack_arg_under_construction says whether a stack
3637 arg is being constructed at the old stack level.
3638 Pushing the stack gets a clean outgoing argument
3639 block. */
3640 old_stack_arg_under_construction
3641 = stack_arg_under_construction;
3642 stack_arg_under_construction = 0;
3643 /* Make a new map for the new argument list. */
3644 free (stack_usage_map_buf);
3645 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3646 stack_usage_map = stack_usage_map_buf;
3647 highest_outgoing_arg_in_use = 0;
3649 /* We can pass TRUE as the 4th argument because we just
3650 saved the stack pointer and will restore it right after
3651 the call. */
3652 allocate_dynamic_stack_space (push_size, 0,
3653 BIGGEST_ALIGNMENT, true);
3656 /* If argument evaluation might modify the stack pointer,
3657 copy the address of the argument list to a register. */
3658 for (i = 0; i < num_actuals; i++)
3659 if (args[i].pass_on_stack)
3661 argblock = copy_addr_to_reg (argblock);
3662 break;
3666 compute_argument_addresses (args, argblock, num_actuals);
3668 /* Stack is properly aligned, pops can't safely be deferred during
3669 the evaluation of the arguments. */
3670 NO_DEFER_POP;
3672 /* Precompute all register parameters. It isn't safe to compute
3673 anything once we have started filling any specific hard regs.
3674 TLS symbols sometimes need a call to resolve. Precompute
3675 register parameters before any stack pointer manipulation
3676 to avoid unaligned stack in the called function. */
3677 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3679 OK_DEFER_POP;
3681 /* Perform stack alignment before the first push (the last arg). */
3682 if (argblock == 0
3683 && adjusted_args_size.constant > reg_parm_stack_space
3684 && adjusted_args_size.constant != unadjusted_args_size)
3686 /* When the stack adjustment is pending, we get better code
3687 by combining the adjustments. */
3688 if (pending_stack_adjust
3689 && ! inhibit_defer_pop)
3691 pending_stack_adjust
3692 = (combine_pending_stack_adjustment_and_call
3693 (unadjusted_args_size,
3694 &adjusted_args_size,
3695 preferred_unit_stack_boundary));
3696 do_pending_stack_adjust ();
3698 else if (argblock == 0)
3699 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3700 - unadjusted_args_size));
3702 /* Now that the stack is properly aligned, pops can't safely
3703 be deferred during the evaluation of the arguments. */
3704 NO_DEFER_POP;
3706 /* Record the maximum pushed stack space size. We need to delay
3707 doing it this far to take into account the optimization done
3708 by combine_pending_stack_adjustment_and_call. */
3709 if (flag_stack_usage_info
3710 && !ACCUMULATE_OUTGOING_ARGS
3711 && pass
3712 && adjusted_args_size.var == 0)
3714 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3715 if (pushed > current_function_pushed_stack_size)
3716 current_function_pushed_stack_size = pushed;
3719 funexp = rtx_for_function_call (fndecl, addr);
3721 if (CALL_EXPR_STATIC_CHAIN (exp))
3722 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3723 else
3724 static_chain_value = 0;
3726 #ifdef REG_PARM_STACK_SPACE
3727 /* Save the fixed argument area if it's part of the caller's frame and
3728 is clobbered by argument setup for this call. */
3729 if (ACCUMULATE_OUTGOING_ARGS && pass)
3730 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3731 &low_to_save, &high_to_save);
3732 #endif
3734 /* Now store (and compute if necessary) all non-register parms.
3735 These come before register parms, since they can require block-moves,
3736 which could clobber the registers used for register parms.
3737 Parms which have partial registers are not stored here,
3738 but we do preallocate space here if they want that. */
3740 for (i = 0; i < num_actuals; i++)
3742 /* Delay bounds until all other args are stored. */
3743 if (POINTER_BOUNDS_P (args[i].tree_value))
3744 continue;
3745 else if (args[i].reg == 0 || args[i].pass_on_stack)
3747 rtx_insn *before_arg = get_last_insn ();
3749 /* We don't allow passing huge (> 2^30 B) arguments
3750 by value. It would cause an overflow later on. */
3751 if (adjusted_args_size.constant
3752 >= (1 << (HOST_BITS_PER_INT - 2)))
3754 sorry ("passing too large argument on stack");
3755 continue;
3758 if (store_one_arg (&args[i], argblock, flags,
3759 adjusted_args_size.var != 0,
3760 reg_parm_stack_space)
3761 || (pass == 0
3762 && check_sibcall_argument_overlap (before_arg,
3763 &args[i], 1)))
3764 sibcall_failure = 1;
3767 if (args[i].stack)
3768 call_fusage
3769 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3770 gen_rtx_USE (VOIDmode, args[i].stack),
3771 call_fusage);
3774 /* If we have a parm that is passed in registers but not in memory
3775 and whose alignment does not permit a direct copy into registers,
3776 make a group of pseudos that correspond to each register that we
3777 will later fill. */
3778 if (STRICT_ALIGNMENT)
3779 store_unaligned_arguments_into_pseudos (args, num_actuals);
3781 /* Now store any partially-in-registers parm.
3782 This is the last place a block-move can happen. */
3783 if (reg_parm_seen)
3784 for (i = 0; i < num_actuals; i++)
3785 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3787 rtx_insn *before_arg = get_last_insn ();
3789 /* On targets with weird calling conventions (e.g. PA) it's
3790 hard to ensure that all cases of argument overlap between
3791 stack and registers work. Play it safe and bail out. */
3792 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3794 sibcall_failure = 1;
3795 break;
3798 if (store_one_arg (&args[i], argblock, flags,
3799 adjusted_args_size.var != 0,
3800 reg_parm_stack_space)
3801 || (pass == 0
3802 && check_sibcall_argument_overlap (before_arg,
3803 &args[i], 1)))
3804 sibcall_failure = 1;
3807 bool any_regs = false;
3808 for (i = 0; i < num_actuals; i++)
3809 if (args[i].reg != NULL_RTX)
3811 any_regs = true;
3812 targetm.calls.call_args (args[i].reg, funtype);
3814 if (!any_regs)
3815 targetm.calls.call_args (pc_rtx, funtype);
3817 /* Figure out the register where the value, if any, will come back. */
3818 valreg = 0;
3819 valbnd = 0;
3820 if (TYPE_MODE (rettype) != VOIDmode
3821 && ! structure_value_addr)
3823 if (pcc_struct_value)
3825 valreg = hard_function_value (build_pointer_type (rettype),
3826 fndecl, NULL, (pass == 0));
3827 if (CALL_WITH_BOUNDS_P (exp))
3828 valbnd = targetm.calls.
3829 chkp_function_value_bounds (build_pointer_type (rettype),
3830 fndecl, (pass == 0));
3832 else
3834 valreg = hard_function_value (rettype, fndecl, fntype,
3835 (pass == 0));
3836 if (CALL_WITH_BOUNDS_P (exp))
3837 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3838 fndecl,
3839 (pass == 0));
3842 /* If VALREG is a PARALLEL whose first member has a zero
3843 offset, use that. This is for targets such as m68k that
3844 return the same value in multiple places. */
3845 if (GET_CODE (valreg) == PARALLEL)
3847 rtx elem = XVECEXP (valreg, 0, 0);
3848 rtx where = XEXP (elem, 0);
3849 rtx offset = XEXP (elem, 1);
3850 if (offset == const0_rtx
3851 && GET_MODE (where) == GET_MODE (valreg))
3852 valreg = where;
3856 /* Store all bounds not passed in registers. */
3857 for (i = 0; i < num_actuals; i++)
3859 if (POINTER_BOUNDS_P (args[i].tree_value)
3860 && !args[i].reg)
3861 store_bounds (&args[i],
3862 args[i].pointer_arg == -1
3863 ? NULL
3864 : &args[args[i].pointer_arg]);
3867 /* If register arguments require space on the stack and stack space
3868 was not preallocated, allocate stack space here for arguments
3869 passed in registers. */
3870 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3871 && !ACCUMULATE_OUTGOING_ARGS
3872 && must_preallocate == 0 && reg_parm_stack_space > 0)
3873 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3875 /* Pass the function the address in which to return a
3876 structure value. */
3877 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3879 structure_value_addr
3880 = convert_memory_address (Pmode, structure_value_addr);
3881 emit_move_insn (struct_value,
3882 force_reg (Pmode,
3883 force_operand (structure_value_addr,
3884 NULL_RTX)));
3886 if (REG_P (struct_value))
3887 use_reg (&call_fusage, struct_value);
3890 after_args = get_last_insn ();
3891 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3892 static_chain_value, &call_fusage,
3893 reg_parm_seen, flags);
3895 load_register_parameters (args, num_actuals, &call_fusage, flags,
3896 pass == 0, &sibcall_failure);
3898 /* Save a pointer to the last insn before the call, so that we can
3899 later safely search backwards to find the CALL_INSN. */
3900 before_call = get_last_insn ();
3902 /* Set up next argument register. For sibling calls on machines
3903 with register windows this should be the incoming register. */
3904 if (pass == 0)
3905 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3906 VOIDmode,
3907 void_type_node,
3908 true);
3909 else
3910 next_arg_reg = targetm.calls.function_arg (args_so_far,
3911 VOIDmode, void_type_node,
3912 true);
3914 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3916 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3917 arg_nr = num_actuals - arg_nr - 1;
3918 if (arg_nr >= 0
3919 && arg_nr < num_actuals
3920 && args[arg_nr].reg
3921 && valreg
3922 && REG_P (valreg)
3923 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3924 call_fusage
3925 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3926 gen_rtx_SET (valreg, args[arg_nr].reg),
3927 call_fusage);
3929 /* All arguments and registers used for the call must be set up by
3930 now! */
3932 /* Stack must be properly aligned now. */
3933 gcc_assert (!pass
3934 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3936 /* Generate the actual call instruction. */
3937 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3938 adjusted_args_size.constant, struct_value_size,
3939 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3940 flags, args_so_far);
3942 if (flag_ipa_ra)
3944 rtx_call_insn *last;
3945 rtx datum = NULL_RTX;
3946 if (fndecl != NULL_TREE)
3948 datum = XEXP (DECL_RTL (fndecl), 0);
3949 gcc_assert (datum != NULL_RTX
3950 && GET_CODE (datum) == SYMBOL_REF);
3952 last = last_call_insn ();
3953 add_reg_note (last, REG_CALL_DECL, datum);
3956 /* If the call setup or the call itself overlaps with anything
3957 of the argument setup we probably clobbered our call address.
3958 In that case we can't do sibcalls. */
3959 if (pass == 0
3960 && check_sibcall_argument_overlap (after_args, 0, 0))
3961 sibcall_failure = 1;
3963 /* If a non-BLKmode value is returned at the most significant end
3964 of a register, shift the register right by the appropriate amount
3965 and update VALREG accordingly. BLKmode values are handled by the
3966 group load/store machinery below. */
3967 if (!structure_value_addr
3968 && !pcc_struct_value
3969 && TYPE_MODE (rettype) != VOIDmode
3970 && TYPE_MODE (rettype) != BLKmode
3971 && REG_P (valreg)
3972 && targetm.calls.return_in_msb (rettype))
3974 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3975 sibcall_failure = 1;
3976 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3979 if (pass && (flags & ECF_MALLOC))
3981 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3982 rtx_insn *last, *insns;
3984 /* The return value from a malloc-like function is a pointer. */
3985 if (TREE_CODE (rettype) == POINTER_TYPE)
3986 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3988 emit_move_insn (temp, valreg);
3990 /* The return value from a malloc-like function can not alias
3991 anything else. */
3992 last = get_last_insn ();
3993 add_reg_note (last, REG_NOALIAS, temp);
3995 /* Write out the sequence. */
3996 insns = get_insns ();
3997 end_sequence ();
3998 emit_insn (insns);
3999 valreg = temp;
4002 /* For calls to `setjmp', etc., inform
4003 function.c:setjmp_warnings that it should complain if
4004 nonvolatile values are live. For functions that cannot
4005 return, inform flow that control does not fall through. */
4007 if ((flags & ECF_NORETURN) || pass == 0)
4009 /* The barrier must be emitted
4010 immediately after the CALL_INSN. Some ports emit more
4011 than just a CALL_INSN above, so we must search for it here. */
4013 rtx_insn *last = get_last_insn ();
4014 while (!CALL_P (last))
4016 last = PREV_INSN (last);
4017 /* There was no CALL_INSN? */
4018 gcc_assert (last != before_call);
4021 emit_barrier_after (last);
4023 /* Stack adjustments after a noreturn call are dead code.
4024 However when NO_DEFER_POP is in effect, we must preserve
4025 stack_pointer_delta. */
4026 if (inhibit_defer_pop == 0)
4028 stack_pointer_delta = old_stack_allocated;
4029 pending_stack_adjust = 0;
4033 /* If value type not void, return an rtx for the value. */
4035 if (TYPE_MODE (rettype) == VOIDmode
4036 || ignore)
4037 target = const0_rtx;
4038 else if (structure_value_addr)
4040 if (target == 0 || !MEM_P (target))
4042 target
4043 = gen_rtx_MEM (TYPE_MODE (rettype),
4044 memory_address (TYPE_MODE (rettype),
4045 structure_value_addr));
4046 set_mem_attributes (target, rettype, 1);
4049 else if (pcc_struct_value)
4051 /* This is the special C++ case where we need to
4052 know what the true target was. We take care to
4053 never use this value more than once in one expression. */
4054 target = gen_rtx_MEM (TYPE_MODE (rettype),
4055 copy_to_reg (valreg));
4056 set_mem_attributes (target, rettype, 1);
4058 /* Handle calls that return values in multiple non-contiguous locations.
4059 The Irix 6 ABI has examples of this. */
4060 else if (GET_CODE (valreg) == PARALLEL)
4062 if (target == 0)
4063 target = emit_group_move_into_temps (valreg);
4064 else if (rtx_equal_p (target, valreg))
4066 else if (GET_CODE (target) == PARALLEL)
4067 /* Handle the result of a emit_group_move_into_temps
4068 call in the previous pass. */
4069 emit_group_move (target, valreg);
4070 else
4071 emit_group_store (target, valreg, rettype,
4072 int_size_in_bytes (rettype));
4074 else if (target
4075 && GET_MODE (target) == TYPE_MODE (rettype)
4076 && GET_MODE (target) == GET_MODE (valreg))
4078 bool may_overlap = false;
4080 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4081 reg to a plain register. */
4082 if (!REG_P (target) || HARD_REGISTER_P (target))
4083 valreg = avoid_likely_spilled_reg (valreg);
4085 /* If TARGET is a MEM in the argument area, and we have
4086 saved part of the argument area, then we can't store
4087 directly into TARGET as it may get overwritten when we
4088 restore the argument save area below. Don't work too
4089 hard though and simply force TARGET to a register if it
4090 is a MEM; the optimizer is quite likely to sort it out. */
4091 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4092 for (i = 0; i < num_actuals; i++)
4093 if (args[i].save_area)
4095 may_overlap = true;
4096 break;
4099 if (may_overlap)
4100 target = copy_to_reg (valreg);
4101 else
4103 /* TARGET and VALREG cannot be equal at this point
4104 because the latter would not have
4105 REG_FUNCTION_VALUE_P true, while the former would if
4106 it were referring to the same register.
4108 If they refer to the same register, this move will be
4109 a no-op, except when function inlining is being
4110 done. */
4111 emit_move_insn (target, valreg);
4113 /* If we are setting a MEM, this code must be executed.
4114 Since it is emitted after the call insn, sibcall
4115 optimization cannot be performed in that case. */
4116 if (MEM_P (target))
4117 sibcall_failure = 1;
4120 else
4121 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4123 /* If we promoted this return value, make the proper SUBREG.
4124 TARGET might be const0_rtx here, so be careful. */
4125 if (REG_P (target)
4126 && TYPE_MODE (rettype) != BLKmode
4127 && GET_MODE (target) != TYPE_MODE (rettype))
4129 tree type = rettype;
4130 int unsignedp = TYPE_UNSIGNED (type);
4131 int offset = 0;
4132 machine_mode pmode;
4134 /* Ensure we promote as expected, and get the new unsignedness. */
4135 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4136 funtype, 1);
4137 gcc_assert (GET_MODE (target) == pmode);
4139 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
4140 && (GET_MODE_SIZE (GET_MODE (target))
4141 > GET_MODE_SIZE (TYPE_MODE (type))))
4143 offset = GET_MODE_SIZE (GET_MODE (target))
4144 - GET_MODE_SIZE (TYPE_MODE (type));
4145 if (! BYTES_BIG_ENDIAN)
4146 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
4147 else if (! WORDS_BIG_ENDIAN)
4148 offset %= UNITS_PER_WORD;
4151 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4152 SUBREG_PROMOTED_VAR_P (target) = 1;
4153 SUBREG_PROMOTED_SET (target, unsignedp);
4156 /* If size of args is variable or this was a constructor call for a stack
4157 argument, restore saved stack-pointer value. */
4159 if (old_stack_level)
4161 rtx_insn *prev = get_last_insn ();
4163 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4164 stack_pointer_delta = old_stack_pointer_delta;
4166 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4168 pending_stack_adjust = old_pending_adj;
4169 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4170 stack_arg_under_construction = old_stack_arg_under_construction;
4171 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4172 stack_usage_map = initial_stack_usage_map;
4173 sibcall_failure = 1;
4175 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4177 #ifdef REG_PARM_STACK_SPACE
4178 if (save_area)
4179 restore_fixed_argument_area (save_area, argblock,
4180 high_to_save, low_to_save);
4181 #endif
4183 /* If we saved any argument areas, restore them. */
4184 for (i = 0; i < num_actuals; i++)
4185 if (args[i].save_area)
4187 machine_mode save_mode = GET_MODE (args[i].save_area);
4188 rtx stack_area
4189 = gen_rtx_MEM (save_mode,
4190 memory_address (save_mode,
4191 XEXP (args[i].stack_slot, 0)));
4193 if (save_mode != BLKmode)
4194 emit_move_insn (stack_area, args[i].save_area);
4195 else
4196 emit_block_move (stack_area, args[i].save_area,
4197 GEN_INT (args[i].locate.size.constant),
4198 BLOCK_OP_CALL_PARM);
4201 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4202 stack_usage_map = initial_stack_usage_map;
4205 /* If this was alloca, record the new stack level. */
4206 if (flags & ECF_MAY_BE_ALLOCA)
4207 record_new_stack_level ();
4209 /* Free up storage we no longer need. */
4210 for (i = 0; i < num_actuals; ++i)
4211 free (args[i].aligned_regs);
4213 targetm.calls.end_call_args ();
4215 insns = get_insns ();
4216 end_sequence ();
4218 if (pass == 0)
4220 tail_call_insns = insns;
4222 /* Restore the pending stack adjustment now that we have
4223 finished generating the sibling call sequence. */
4225 restore_pending_stack_adjust (&save);
4227 /* Prepare arg structure for next iteration. */
4228 for (i = 0; i < num_actuals; i++)
4230 args[i].value = 0;
4231 args[i].aligned_regs = 0;
4232 args[i].stack = 0;
4235 sbitmap_free (stored_args_map);
4236 internal_arg_pointer_exp_state.scan_start = NULL;
4237 internal_arg_pointer_exp_state.cache.release ();
4239 else
4241 normal_call_insns = insns;
4243 /* Verify that we've deallocated all the stack we used. */
4244 gcc_assert ((flags & ECF_NORETURN)
4245 || (old_stack_allocated
4246 == stack_pointer_delta - pending_stack_adjust));
4249 /* If something prevents making this a sibling call,
4250 zero out the sequence. */
4251 if (sibcall_failure)
4252 tail_call_insns = NULL;
4253 else
4254 break;
4257 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4258 arguments too, as argument area is now clobbered by the call. */
4259 if (tail_call_insns)
4261 emit_insn (tail_call_insns);
4262 crtl->tail_call_emit = true;
4264 else
4266 emit_insn (normal_call_insns);
4267 if (try_tail_call)
4268 /* Ideally we'd emit a message for all of the ways that it could
4269 have failed. */
4270 maybe_complain_about_tail_call (exp, "tail call production failed");
4273 currently_expanding_call--;
4275 free (stack_usage_map_buf);
4276 free (args);
4278 /* Join result with returned bounds so caller may use them if needed. */
4279 target = chkp_join_splitted_slot (target, valbnd);
4281 return target;
4284 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4285 this function's incoming arguments.
4287 At the start of RTL generation we know the only REG_EQUIV notes
4288 in the rtl chain are those for incoming arguments, so we can look
4289 for REG_EQUIV notes between the start of the function and the
4290 NOTE_INSN_FUNCTION_BEG.
4292 This is (slight) overkill. We could keep track of the highest
4293 argument we clobber and be more selective in removing notes, but it
4294 does not seem to be worth the effort. */
4296 void
4297 fixup_tail_calls (void)
4299 rtx_insn *insn;
4301 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4303 rtx note;
4305 /* There are never REG_EQUIV notes for the incoming arguments
4306 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4307 if (NOTE_P (insn)
4308 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4309 break;
4311 note = find_reg_note (insn, REG_EQUIV, 0);
4312 if (note)
4313 remove_note (insn, note);
4314 note = find_reg_note (insn, REG_EQUIV, 0);
4315 gcc_assert (!note);
4319 /* Traverse a list of TYPES and expand all complex types into their
4320 components. */
4321 static tree
4322 split_complex_types (tree types)
4324 tree p;
4326 /* Before allocating memory, check for the common case of no complex. */
4327 for (p = types; p; p = TREE_CHAIN (p))
4329 tree type = TREE_VALUE (p);
4330 if (TREE_CODE (type) == COMPLEX_TYPE
4331 && targetm.calls.split_complex_arg (type))
4332 goto found;
4334 return types;
4336 found:
4337 types = copy_list (types);
4339 for (p = types; p; p = TREE_CHAIN (p))
4341 tree complex_type = TREE_VALUE (p);
4343 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4344 && targetm.calls.split_complex_arg (complex_type))
4346 tree next, imag;
4348 /* Rewrite complex type with component type. */
4349 TREE_VALUE (p) = TREE_TYPE (complex_type);
4350 next = TREE_CHAIN (p);
4352 /* Add another component type for the imaginary part. */
4353 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4354 TREE_CHAIN (p) = imag;
4355 TREE_CHAIN (imag) = next;
4357 /* Skip the newly created node. */
4358 p = TREE_CHAIN (p);
4362 return types;
4365 /* Output a library call to function ORGFUN (a SYMBOL_REF rtx)
4366 for a value of mode OUTMODE,
4367 with NARGS different arguments, passed as ARGS.
4368 Store the return value if RETVAL is nonzero: store it in VALUE if
4369 VALUE is nonnull, otherwise pick a convenient location. In either
4370 case return the location of the stored value.
4372 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4373 `const' calls, LCT_PURE for `pure' calls, or another LCT_ value for
4374 other types of library calls. */
4377 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4378 enum libcall_type fn_type,
4379 machine_mode outmode, int nargs, rtx_mode_t *args)
4381 /* Total size in bytes of all the stack-parms scanned so far. */
4382 struct args_size args_size;
4383 /* Size of arguments before any adjustments (such as rounding). */
4384 struct args_size original_args_size;
4385 int argnum;
4386 rtx fun;
4387 /* Todo, choose the correct decl type of orgfun. Sadly this information
4388 isn't present here, so we default to native calling abi here. */
4389 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4390 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4391 int count;
4392 rtx argblock = 0;
4393 CUMULATIVE_ARGS args_so_far_v;
4394 cumulative_args_t args_so_far;
4395 struct arg
4397 rtx value;
4398 machine_mode mode;
4399 rtx reg;
4400 int partial;
4401 struct locate_and_pad_arg_data locate;
4402 rtx save_area;
4404 struct arg *argvec;
4405 int old_inhibit_defer_pop = inhibit_defer_pop;
4406 rtx call_fusage = 0;
4407 rtx mem_value = 0;
4408 rtx valreg;
4409 int pcc_struct_value = 0;
4410 int struct_value_size = 0;
4411 int flags;
4412 int reg_parm_stack_space = 0;
4413 int needed;
4414 rtx_insn *before_call;
4415 bool have_push_fusage;
4416 tree tfom; /* type_for_mode (outmode, 0) */
4418 #ifdef REG_PARM_STACK_SPACE
4419 /* Define the boundary of the register parm stack space that needs to be
4420 save, if any. */
4421 int low_to_save = 0, high_to_save = 0;
4422 rtx save_area = 0; /* Place that it is saved. */
4423 #endif
4425 /* Size of the stack reserved for parameter registers. */
4426 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4427 char *initial_stack_usage_map = stack_usage_map;
4428 char *stack_usage_map_buf = NULL;
4430 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4432 #ifdef REG_PARM_STACK_SPACE
4433 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4434 #endif
4436 /* By default, library functions cannot throw. */
4437 flags = ECF_NOTHROW;
4439 switch (fn_type)
4441 case LCT_NORMAL:
4442 break;
4443 case LCT_CONST:
4444 flags |= ECF_CONST;
4445 break;
4446 case LCT_PURE:
4447 flags |= ECF_PURE;
4448 break;
4449 case LCT_NORETURN:
4450 flags |= ECF_NORETURN;
4451 break;
4452 case LCT_THROW:
4453 flags &= ~ECF_NOTHROW;
4454 break;
4455 case LCT_RETURNS_TWICE:
4456 flags = ECF_RETURNS_TWICE;
4457 break;
4459 fun = orgfun;
4461 /* Ensure current function's preferred stack boundary is at least
4462 what we need. */
4463 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4464 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4466 /* If this kind of value comes back in memory,
4467 decide where in memory it should come back. */
4468 if (outmode != VOIDmode)
4470 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4471 if (aggregate_value_p (tfom, 0))
4473 #ifdef PCC_STATIC_STRUCT_RETURN
4474 rtx pointer_reg
4475 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4476 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4477 pcc_struct_value = 1;
4478 if (value == 0)
4479 value = gen_reg_rtx (outmode);
4480 #else /* not PCC_STATIC_STRUCT_RETURN */
4481 struct_value_size = GET_MODE_SIZE (outmode);
4482 if (value != 0 && MEM_P (value))
4483 mem_value = value;
4484 else
4485 mem_value = assign_temp (tfom, 1, 1);
4486 #endif
4487 /* This call returns a big structure. */
4488 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4491 else
4492 tfom = void_type_node;
4494 /* ??? Unfinished: must pass the memory address as an argument. */
4496 /* Copy all the libcall-arguments out of the varargs data
4497 and into a vector ARGVEC.
4499 Compute how to pass each argument. We only support a very small subset
4500 of the full argument passing conventions to limit complexity here since
4501 library functions shouldn't have many args. */
4503 argvec = XALLOCAVEC (struct arg, nargs + 1);
4504 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4506 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4507 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4508 #else
4509 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4510 #endif
4511 args_so_far = pack_cumulative_args (&args_so_far_v);
4513 args_size.constant = 0;
4514 args_size.var = 0;
4516 count = 0;
4518 push_temp_slots ();
4520 /* If there's a structure value address to be passed,
4521 either pass it in the special place, or pass it as an extra argument. */
4522 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4524 rtx addr = XEXP (mem_value, 0);
4526 nargs++;
4528 /* Make sure it is a reasonable operand for a move or push insn. */
4529 if (!REG_P (addr) && !MEM_P (addr)
4530 && !(CONSTANT_P (addr)
4531 && targetm.legitimate_constant_p (Pmode, addr)))
4532 addr = force_operand (addr, NULL_RTX);
4534 argvec[count].value = addr;
4535 argvec[count].mode = Pmode;
4536 argvec[count].partial = 0;
4538 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4539 Pmode, NULL_TREE, true);
4540 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4541 NULL_TREE, 1) == 0);
4543 locate_and_pad_parm (Pmode, NULL_TREE,
4544 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4546 #else
4547 argvec[count].reg != 0,
4548 #endif
4549 reg_parm_stack_space, 0,
4550 NULL_TREE, &args_size, &argvec[count].locate);
4552 if (argvec[count].reg == 0 || argvec[count].partial != 0
4553 || reg_parm_stack_space > 0)
4554 args_size.constant += argvec[count].locate.size.constant;
4556 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4558 count++;
4561 for (unsigned int i = 0; count < nargs; i++, count++)
4563 rtx val = args[i].first;
4564 machine_mode mode = args[i].second;
4565 int unsigned_p = 0;
4567 /* We cannot convert the arg value to the mode the library wants here;
4568 must do it earlier where we know the signedness of the arg. */
4569 gcc_assert (mode != BLKmode
4570 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4572 /* Make sure it is a reasonable operand for a move or push insn. */
4573 if (!REG_P (val) && !MEM_P (val)
4574 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4575 val = force_operand (val, NULL_RTX);
4577 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4579 rtx slot;
4580 int must_copy
4581 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4583 /* If this was a CONST function, it is now PURE since it now
4584 reads memory. */
4585 if (flags & ECF_CONST)
4587 flags &= ~ECF_CONST;
4588 flags |= ECF_PURE;
4591 if (MEM_P (val) && !must_copy)
4593 tree val_expr = MEM_EXPR (val);
4594 if (val_expr)
4595 mark_addressable (val_expr);
4596 slot = val;
4598 else
4600 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4601 1, 1);
4602 emit_move_insn (slot, val);
4605 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4606 gen_rtx_USE (VOIDmode, slot),
4607 call_fusage);
4608 if (must_copy)
4609 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4610 gen_rtx_CLOBBER (VOIDmode,
4611 slot),
4612 call_fusage);
4614 mode = Pmode;
4615 val = force_operand (XEXP (slot, 0), NULL_RTX);
4618 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4619 argvec[count].mode = mode;
4620 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4621 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4622 NULL_TREE, true);
4624 argvec[count].partial
4625 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4627 if (argvec[count].reg == 0
4628 || argvec[count].partial != 0
4629 || reg_parm_stack_space > 0)
4631 locate_and_pad_parm (mode, NULL_TREE,
4632 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4634 #else
4635 argvec[count].reg != 0,
4636 #endif
4637 reg_parm_stack_space, argvec[count].partial,
4638 NULL_TREE, &args_size, &argvec[count].locate);
4639 args_size.constant += argvec[count].locate.size.constant;
4640 gcc_assert (!argvec[count].locate.size.var);
4642 #ifdef BLOCK_REG_PADDING
4643 else
4644 /* The argument is passed entirely in registers. See at which
4645 end it should be padded. */
4646 argvec[count].locate.where_pad =
4647 BLOCK_REG_PADDING (mode, NULL_TREE,
4648 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4649 #endif
4651 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4654 /* If this machine requires an external definition for library
4655 functions, write one out. */
4656 assemble_external_libcall (fun);
4658 original_args_size = args_size;
4659 args_size.constant = (((args_size.constant
4660 + stack_pointer_delta
4661 + STACK_BYTES - 1)
4662 / STACK_BYTES
4663 * STACK_BYTES)
4664 - stack_pointer_delta);
4666 args_size.constant = MAX (args_size.constant,
4667 reg_parm_stack_space);
4669 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4670 args_size.constant -= reg_parm_stack_space;
4672 if (args_size.constant > crtl->outgoing_args_size)
4673 crtl->outgoing_args_size = args_size.constant;
4675 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4677 int pushed = args_size.constant + pending_stack_adjust;
4678 if (pushed > current_function_pushed_stack_size)
4679 current_function_pushed_stack_size = pushed;
4682 if (ACCUMULATE_OUTGOING_ARGS)
4684 /* Since the stack pointer will never be pushed, it is possible for
4685 the evaluation of a parm to clobber something we have already
4686 written to the stack. Since most function calls on RISC machines
4687 do not use the stack, this is uncommon, but must work correctly.
4689 Therefore, we save any area of the stack that was already written
4690 and that we are using. Here we set up to do this by making a new
4691 stack usage map from the old one.
4693 Another approach might be to try to reorder the argument
4694 evaluations to avoid this conflicting stack usage. */
4696 needed = args_size.constant;
4698 /* Since we will be writing into the entire argument area, the
4699 map must be allocated for its entire size, not just the part that
4700 is the responsibility of the caller. */
4701 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4702 needed += reg_parm_stack_space;
4704 if (ARGS_GROW_DOWNWARD)
4705 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4706 needed + 1);
4707 else
4708 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4710 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4711 stack_usage_map = stack_usage_map_buf;
4713 if (initial_highest_arg_in_use)
4714 memcpy (stack_usage_map, initial_stack_usage_map,
4715 initial_highest_arg_in_use);
4717 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4718 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4719 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4720 needed = 0;
4722 /* We must be careful to use virtual regs before they're instantiated,
4723 and real regs afterwards. Loop optimization, for example, can create
4724 new libcalls after we've instantiated the virtual regs, and if we
4725 use virtuals anyway, they won't match the rtl patterns. */
4727 if (virtuals_instantiated)
4728 argblock = plus_constant (Pmode, stack_pointer_rtx,
4729 STACK_POINTER_OFFSET);
4730 else
4731 argblock = virtual_outgoing_args_rtx;
4733 else
4735 if (!PUSH_ARGS)
4736 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4739 /* We push args individually in reverse order, perform stack alignment
4740 before the first push (the last arg). */
4741 if (argblock == 0)
4742 anti_adjust_stack (GEN_INT (args_size.constant
4743 - original_args_size.constant));
4745 argnum = nargs - 1;
4747 #ifdef REG_PARM_STACK_SPACE
4748 if (ACCUMULATE_OUTGOING_ARGS)
4750 /* The argument list is the property of the called routine and it
4751 may clobber it. If the fixed area has been used for previous
4752 parameters, we must save and restore it. */
4753 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4754 &low_to_save, &high_to_save);
4756 #endif
4758 /* When expanding a normal call, args are stored in push order,
4759 which is the reverse of what we have here. */
4760 bool any_regs = false;
4761 for (int i = nargs; i-- > 0; )
4762 if (argvec[i].reg != NULL_RTX)
4764 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4765 any_regs = true;
4767 if (!any_regs)
4768 targetm.calls.call_args (pc_rtx, NULL_TREE);
4770 /* Push the args that need to be pushed. */
4772 have_push_fusage = false;
4774 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4775 are to be pushed. */
4776 for (count = 0; count < nargs; count++, argnum--)
4778 machine_mode mode = argvec[argnum].mode;
4779 rtx val = argvec[argnum].value;
4780 rtx reg = argvec[argnum].reg;
4781 int partial = argvec[argnum].partial;
4782 unsigned int parm_align = argvec[argnum].locate.boundary;
4783 int lower_bound = 0, upper_bound = 0, i;
4785 if (! (reg != 0 && partial == 0))
4787 rtx use;
4789 if (ACCUMULATE_OUTGOING_ARGS)
4791 /* If this is being stored into a pre-allocated, fixed-size,
4792 stack area, save any previous data at that location. */
4794 if (ARGS_GROW_DOWNWARD)
4796 /* stack_slot is negative, but we want to index stack_usage_map
4797 with positive values. */
4798 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4799 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4801 else
4803 lower_bound = argvec[argnum].locate.slot_offset.constant;
4804 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4807 i = lower_bound;
4808 /* Don't worry about things in the fixed argument area;
4809 it has already been saved. */
4810 if (i < reg_parm_stack_space)
4811 i = reg_parm_stack_space;
4812 while (i < upper_bound && stack_usage_map[i] == 0)
4813 i++;
4815 if (i < upper_bound)
4817 /* We need to make a save area. */
4818 unsigned int size
4819 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4820 machine_mode save_mode
4821 = mode_for_size (size, MODE_INT, 1);
4822 rtx adr
4823 = plus_constant (Pmode, argblock,
4824 argvec[argnum].locate.offset.constant);
4825 rtx stack_area
4826 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4828 if (save_mode == BLKmode)
4830 argvec[argnum].save_area
4831 = assign_stack_temp (BLKmode,
4832 argvec[argnum].locate.size.constant
4835 emit_block_move (validize_mem
4836 (copy_rtx (argvec[argnum].save_area)),
4837 stack_area,
4838 GEN_INT (argvec[argnum].locate.size.constant),
4839 BLOCK_OP_CALL_PARM);
4841 else
4843 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4845 emit_move_insn (argvec[argnum].save_area, stack_area);
4850 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4851 partial, reg, 0, argblock,
4852 GEN_INT (argvec[argnum].locate.offset.constant),
4853 reg_parm_stack_space,
4854 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4856 /* Now mark the segment we just used. */
4857 if (ACCUMULATE_OUTGOING_ARGS)
4858 for (i = lower_bound; i < upper_bound; i++)
4859 stack_usage_map[i] = 1;
4861 NO_DEFER_POP;
4863 /* Indicate argument access so that alias.c knows that these
4864 values are live. */
4865 if (argblock)
4866 use = plus_constant (Pmode, argblock,
4867 argvec[argnum].locate.offset.constant);
4868 else if (have_push_fusage)
4869 continue;
4870 else
4872 /* When arguments are pushed, trying to tell alias.c where
4873 exactly this argument is won't work, because the
4874 auto-increment causes confusion. So we merely indicate
4875 that we access something with a known mode somewhere on
4876 the stack. */
4877 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4878 gen_rtx_SCRATCH (Pmode));
4879 have_push_fusage = true;
4881 use = gen_rtx_MEM (argvec[argnum].mode, use);
4882 use = gen_rtx_USE (VOIDmode, use);
4883 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4887 argnum = nargs - 1;
4889 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4891 /* Now load any reg parms into their regs. */
4893 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4894 are to be pushed. */
4895 for (count = 0; count < nargs; count++, argnum--)
4897 machine_mode mode = argvec[argnum].mode;
4898 rtx val = argvec[argnum].value;
4899 rtx reg = argvec[argnum].reg;
4900 int partial = argvec[argnum].partial;
4901 #ifdef BLOCK_REG_PADDING
4902 int size = 0;
4903 #endif
4905 /* Handle calls that pass values in multiple non-contiguous
4906 locations. The PA64 has examples of this for library calls. */
4907 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4908 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4909 else if (reg != 0 && partial == 0)
4911 emit_move_insn (reg, val);
4912 #ifdef BLOCK_REG_PADDING
4913 size = GET_MODE_SIZE (argvec[argnum].mode);
4915 /* Copied from load_register_parameters. */
4917 /* Handle case where we have a value that needs shifting
4918 up to the msb. eg. a QImode value and we're padding
4919 upward on a BYTES_BIG_ENDIAN machine. */
4920 if (size < UNITS_PER_WORD
4921 && (argvec[argnum].locate.where_pad
4922 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
4924 rtx x;
4925 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4927 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4928 report the whole reg as used. Strictly speaking, the
4929 call only uses SIZE bytes at the msb end, but it doesn't
4930 seem worth generating rtl to say that. */
4931 reg = gen_rtx_REG (word_mode, REGNO (reg));
4932 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4933 if (x != reg)
4934 emit_move_insn (reg, x);
4936 #endif
4939 NO_DEFER_POP;
4942 /* Any regs containing parms remain in use through the call. */
4943 for (count = 0; count < nargs; count++)
4945 rtx reg = argvec[count].reg;
4946 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4947 use_group_regs (&call_fusage, reg);
4948 else if (reg != 0)
4950 int partial = argvec[count].partial;
4951 if (partial)
4953 int nregs;
4954 gcc_assert (partial % UNITS_PER_WORD == 0);
4955 nregs = partial / UNITS_PER_WORD;
4956 use_regs (&call_fusage, REGNO (reg), nregs);
4958 else
4959 use_reg (&call_fusage, reg);
4963 /* Pass the function the address in which to return a structure value. */
4964 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4966 emit_move_insn (struct_value,
4967 force_reg (Pmode,
4968 force_operand (XEXP (mem_value, 0),
4969 NULL_RTX)));
4970 if (REG_P (struct_value))
4971 use_reg (&call_fusage, struct_value);
4974 /* Don't allow popping to be deferred, since then
4975 cse'ing of library calls could delete a call and leave the pop. */
4976 NO_DEFER_POP;
4977 valreg = (mem_value == 0 && outmode != VOIDmode
4978 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4980 /* Stack must be properly aligned now. */
4981 gcc_assert (!(stack_pointer_delta
4982 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4984 before_call = get_last_insn ();
4986 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4987 will set inhibit_defer_pop to that value. */
4988 /* The return type is needed to decide how many bytes the function pops.
4989 Signedness plays no role in that, so for simplicity, we pretend it's
4990 always signed. We also assume that the list of arguments passed has
4991 no impact, so we pretend it is unknown. */
4993 emit_call_1 (fun, NULL,
4994 get_identifier (XSTR (orgfun, 0)),
4995 build_function_type (tfom, NULL_TREE),
4996 original_args_size.constant, args_size.constant,
4997 struct_value_size,
4998 targetm.calls.function_arg (args_so_far,
4999 VOIDmode, void_type_node, true),
5000 valreg,
5001 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
5003 if (flag_ipa_ra)
5005 rtx datum = orgfun;
5006 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
5007 rtx_call_insn *last = last_call_insn ();
5008 add_reg_note (last, REG_CALL_DECL, datum);
5011 /* Right-shift returned value if necessary. */
5012 if (!pcc_struct_value
5013 && TYPE_MODE (tfom) != BLKmode
5014 && targetm.calls.return_in_msb (tfom))
5016 shift_return_value (TYPE_MODE (tfom), false, valreg);
5017 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5020 targetm.calls.end_call_args ();
5022 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5023 that it should complain if nonvolatile values are live. For
5024 functions that cannot return, inform flow that control does not
5025 fall through. */
5026 if (flags & ECF_NORETURN)
5028 /* The barrier note must be emitted
5029 immediately after the CALL_INSN. Some ports emit more than
5030 just a CALL_INSN above, so we must search for it here. */
5031 rtx_insn *last = get_last_insn ();
5032 while (!CALL_P (last))
5034 last = PREV_INSN (last);
5035 /* There was no CALL_INSN? */
5036 gcc_assert (last != before_call);
5039 emit_barrier_after (last);
5042 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5043 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5044 if (flags & ECF_NOTHROW)
5046 rtx_insn *last = get_last_insn ();
5047 while (!CALL_P (last))
5049 last = PREV_INSN (last);
5050 /* There was no CALL_INSN? */
5051 gcc_assert (last != before_call);
5054 make_reg_eh_region_note_nothrow_nononlocal (last);
5057 /* Now restore inhibit_defer_pop to its actual original value. */
5058 OK_DEFER_POP;
5060 pop_temp_slots ();
5062 /* Copy the value to the right place. */
5063 if (outmode != VOIDmode && retval)
5065 if (mem_value)
5067 if (value == 0)
5068 value = mem_value;
5069 if (value != mem_value)
5070 emit_move_insn (value, mem_value);
5072 else if (GET_CODE (valreg) == PARALLEL)
5074 if (value == 0)
5075 value = gen_reg_rtx (outmode);
5076 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5078 else
5080 /* Convert to the proper mode if a promotion has been active. */
5081 if (GET_MODE (valreg) != outmode)
5083 int unsignedp = TYPE_UNSIGNED (tfom);
5085 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5086 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5087 == GET_MODE (valreg));
5088 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5091 if (value != 0)
5092 emit_move_insn (value, valreg);
5093 else
5094 value = valreg;
5098 if (ACCUMULATE_OUTGOING_ARGS)
5100 #ifdef REG_PARM_STACK_SPACE
5101 if (save_area)
5102 restore_fixed_argument_area (save_area, argblock,
5103 high_to_save, low_to_save);
5104 #endif
5106 /* If we saved any argument areas, restore them. */
5107 for (count = 0; count < nargs; count++)
5108 if (argvec[count].save_area)
5110 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5111 rtx adr = plus_constant (Pmode, argblock,
5112 argvec[count].locate.offset.constant);
5113 rtx stack_area = gen_rtx_MEM (save_mode,
5114 memory_address (save_mode, adr));
5116 if (save_mode == BLKmode)
5117 emit_block_move (stack_area,
5118 validize_mem
5119 (copy_rtx (argvec[count].save_area)),
5120 GEN_INT (argvec[count].locate.size.constant),
5121 BLOCK_OP_CALL_PARM);
5122 else
5123 emit_move_insn (stack_area, argvec[count].save_area);
5126 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5127 stack_usage_map = initial_stack_usage_map;
5130 free (stack_usage_map_buf);
5132 return value;
5137 /* Store pointer bounds argument ARG into Bounds Table entry
5138 associated with PARM. */
5139 static void
5140 store_bounds (struct arg_data *arg, struct arg_data *parm)
5142 rtx slot = NULL, ptr = NULL, addr = NULL;
5144 /* We may pass bounds not associated with any pointer. */
5145 if (!parm)
5147 gcc_assert (arg->special_slot);
5148 slot = arg->special_slot;
5149 ptr = const0_rtx;
5151 /* Find pointer associated with bounds and where it is
5152 passed. */
5153 else
5155 if (!parm->reg)
5157 gcc_assert (!arg->special_slot);
5159 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5161 else if (REG_P (parm->reg))
5163 gcc_assert (arg->special_slot);
5164 slot = arg->special_slot;
5166 if (MEM_P (parm->value))
5167 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5168 else if (REG_P (parm->value))
5169 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5170 else
5172 gcc_assert (!arg->pointer_offset);
5173 ptr = parm->value;
5176 else
5178 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5180 gcc_assert (arg->special_slot);
5181 slot = arg->special_slot;
5183 if (parm->parallel_value)
5184 ptr = chkp_get_value_with_offs (parm->parallel_value,
5185 GEN_INT (arg->pointer_offset));
5186 else
5187 gcc_unreachable ();
5191 /* Expand bounds. */
5192 if (!arg->value)
5193 arg->value = expand_normal (arg->tree_value);
5195 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5198 /* Store a single argument for a function call
5199 into the register or memory area where it must be passed.
5200 *ARG describes the argument value and where to pass it.
5202 ARGBLOCK is the address of the stack-block for all the arguments,
5203 or 0 on a machine where arguments are pushed individually.
5205 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5206 so must be careful about how the stack is used.
5208 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5209 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5210 that we need not worry about saving and restoring the stack.
5212 FNDECL is the declaration of the function we are calling.
5214 Return nonzero if this arg should cause sibcall failure,
5215 zero otherwise. */
5217 static int
5218 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5219 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5221 tree pval = arg->tree_value;
5222 rtx reg = 0;
5223 int partial = 0;
5224 int used = 0;
5225 int i, lower_bound = 0, upper_bound = 0;
5226 int sibcall_failure = 0;
5228 if (TREE_CODE (pval) == ERROR_MARK)
5229 return 1;
5231 /* Push a new temporary level for any temporaries we make for
5232 this argument. */
5233 push_temp_slots ();
5235 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5237 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5238 save any previous data at that location. */
5239 if (argblock && ! variable_size && arg->stack)
5241 if (ARGS_GROW_DOWNWARD)
5243 /* stack_slot is negative, but we want to index stack_usage_map
5244 with positive values. */
5245 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5246 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
5247 else
5248 upper_bound = 0;
5250 lower_bound = upper_bound - arg->locate.size.constant;
5252 else
5254 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5255 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
5256 else
5257 lower_bound = 0;
5259 upper_bound = lower_bound + arg->locate.size.constant;
5262 i = lower_bound;
5263 /* Don't worry about things in the fixed argument area;
5264 it has already been saved. */
5265 if (i < reg_parm_stack_space)
5266 i = reg_parm_stack_space;
5267 while (i < upper_bound && stack_usage_map[i] == 0)
5268 i++;
5270 if (i < upper_bound)
5272 /* We need to make a save area. */
5273 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
5274 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
5275 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5276 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5278 if (save_mode == BLKmode)
5280 arg->save_area
5281 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5282 preserve_temp_slots (arg->save_area);
5283 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5284 stack_area,
5285 GEN_INT (arg->locate.size.constant),
5286 BLOCK_OP_CALL_PARM);
5288 else
5290 arg->save_area = gen_reg_rtx (save_mode);
5291 emit_move_insn (arg->save_area, stack_area);
5297 /* If this isn't going to be placed on both the stack and in registers,
5298 set up the register and number of words. */
5299 if (! arg->pass_on_stack)
5301 if (flags & ECF_SIBCALL)
5302 reg = arg->tail_call_reg;
5303 else
5304 reg = arg->reg;
5305 partial = arg->partial;
5308 /* Being passed entirely in a register. We shouldn't be called in
5309 this case. */
5310 gcc_assert (reg == 0 || partial != 0);
5312 /* If this arg needs special alignment, don't load the registers
5313 here. */
5314 if (arg->n_aligned_regs != 0)
5315 reg = 0;
5317 /* If this is being passed partially in a register, we can't evaluate
5318 it directly into its stack slot. Otherwise, we can. */
5319 if (arg->value == 0)
5321 /* stack_arg_under_construction is nonzero if a function argument is
5322 being evaluated directly into the outgoing argument list and
5323 expand_call must take special action to preserve the argument list
5324 if it is called recursively.
5326 For scalar function arguments stack_usage_map is sufficient to
5327 determine which stack slots must be saved and restored. Scalar
5328 arguments in general have pass_on_stack == 0.
5330 If this argument is initialized by a function which takes the
5331 address of the argument (a C++ constructor or a C function
5332 returning a BLKmode structure), then stack_usage_map is
5333 insufficient and expand_call must push the stack around the
5334 function call. Such arguments have pass_on_stack == 1.
5336 Note that it is always safe to set stack_arg_under_construction,
5337 but this generates suboptimal code if set when not needed. */
5339 if (arg->pass_on_stack)
5340 stack_arg_under_construction++;
5342 arg->value = expand_expr (pval,
5343 (partial
5344 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5345 ? NULL_RTX : arg->stack,
5346 VOIDmode, EXPAND_STACK_PARM);
5348 /* If we are promoting object (or for any other reason) the mode
5349 doesn't agree, convert the mode. */
5351 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5352 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5353 arg->value, arg->unsignedp);
5355 if (arg->pass_on_stack)
5356 stack_arg_under_construction--;
5359 /* Check for overlap with already clobbered argument area. */
5360 if ((flags & ECF_SIBCALL)
5361 && MEM_P (arg->value)
5362 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
5363 arg->locate.size.constant))
5364 sibcall_failure = 1;
5366 /* Don't allow anything left on stack from computation
5367 of argument to alloca. */
5368 if (flags & ECF_MAY_BE_ALLOCA)
5369 do_pending_stack_adjust ();
5371 if (arg->value == arg->stack)
5372 /* If the value is already in the stack slot, we are done. */
5374 else if (arg->mode != BLKmode)
5376 int size;
5377 unsigned int parm_align;
5379 /* Argument is a scalar, not entirely passed in registers.
5380 (If part is passed in registers, arg->partial says how much
5381 and emit_push_insn will take care of putting it there.)
5383 Push it, and if its size is less than the
5384 amount of space allocated to it,
5385 also bump stack pointer by the additional space.
5386 Note that in C the default argument promotions
5387 will prevent such mismatches. */
5389 size = GET_MODE_SIZE (arg->mode);
5390 /* Compute how much space the push instruction will push.
5391 On many machines, pushing a byte will advance the stack
5392 pointer by a halfword. */
5393 #ifdef PUSH_ROUNDING
5394 size = PUSH_ROUNDING (size);
5395 #endif
5396 used = size;
5398 /* Compute how much space the argument should get:
5399 round up to a multiple of the alignment for arguments. */
5400 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5401 != PAD_NONE)
5402 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
5403 / (PARM_BOUNDARY / BITS_PER_UNIT))
5404 * (PARM_BOUNDARY / BITS_PER_UNIT));
5406 /* Compute the alignment of the pushed argument. */
5407 parm_align = arg->locate.boundary;
5408 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5409 == PAD_DOWNWARD)
5411 int pad = used - size;
5412 if (pad)
5414 unsigned int pad_align = least_bit_hwi (pad) * BITS_PER_UNIT;
5415 parm_align = MIN (parm_align, pad_align);
5419 /* This isn't already where we want it on the stack, so put it there.
5420 This can either be done with push or copy insns. */
5421 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
5422 parm_align, partial, reg, used - size, argblock,
5423 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5424 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5425 sibcall_failure = 1;
5427 /* Unless this is a partially-in-register argument, the argument is now
5428 in the stack. */
5429 if (partial == 0)
5430 arg->value = arg->stack;
5432 else
5434 /* BLKmode, at least partly to be pushed. */
5436 unsigned int parm_align;
5437 int excess;
5438 rtx size_rtx;
5440 /* Pushing a nonscalar.
5441 If part is passed in registers, PARTIAL says how much
5442 and emit_push_insn will take care of putting it there. */
5444 /* Round its size up to a multiple
5445 of the allocation unit for arguments. */
5447 if (arg->locate.size.var != 0)
5449 excess = 0;
5450 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5452 else
5454 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5455 for BLKmode is careful to avoid it. */
5456 excess = (arg->locate.size.constant
5457 - int_size_in_bytes (TREE_TYPE (pval))
5458 + partial);
5459 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
5460 NULL_RTX, TYPE_MODE (sizetype),
5461 EXPAND_NORMAL);
5464 parm_align = arg->locate.boundary;
5466 /* When an argument is padded down, the block is aligned to
5467 PARM_BOUNDARY, but the actual argument isn't. */
5468 if (targetm.calls.function_arg_padding (arg->mode, TREE_TYPE (pval))
5469 == PAD_DOWNWARD)
5471 if (arg->locate.size.var)
5472 parm_align = BITS_PER_UNIT;
5473 else if (excess)
5475 unsigned int excess_align = least_bit_hwi (excess) * BITS_PER_UNIT;
5476 parm_align = MIN (parm_align, excess_align);
5480 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5482 /* emit_push_insn might not work properly if arg->value and
5483 argblock + arg->locate.offset areas overlap. */
5484 rtx x = arg->value;
5485 int i = 0;
5487 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5488 || (GET_CODE (XEXP (x, 0)) == PLUS
5489 && XEXP (XEXP (x, 0), 0) ==
5490 crtl->args.internal_arg_pointer
5491 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5493 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5494 i = INTVAL (XEXP (XEXP (x, 0), 1));
5496 /* arg.locate doesn't contain the pretend_args_size offset,
5497 it's part of argblock. Ensure we don't count it in I. */
5498 if (STACK_GROWS_DOWNWARD)
5499 i -= crtl->args.pretend_args_size;
5500 else
5501 i += crtl->args.pretend_args_size;
5503 /* expand_call should ensure this. */
5504 gcc_assert (!arg->locate.offset.var
5505 && arg->locate.size.var == 0
5506 && CONST_INT_P (size_rtx));
5508 if (arg->locate.offset.constant > i)
5510 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
5511 sibcall_failure = 1;
5513 else if (arg->locate.offset.constant < i)
5515 /* Use arg->locate.size.constant instead of size_rtx
5516 because we only care about the part of the argument
5517 on the stack. */
5518 if (i < (arg->locate.offset.constant
5519 + arg->locate.size.constant))
5520 sibcall_failure = 1;
5522 else
5524 /* Even though they appear to be at the same location,
5525 if part of the outgoing argument is in registers,
5526 they aren't really at the same location. Check for
5527 this by making sure that the incoming size is the
5528 same as the outgoing size. */
5529 if (arg->locate.size.constant != INTVAL (size_rtx))
5530 sibcall_failure = 1;
5535 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5536 parm_align, partial, reg, excess, argblock,
5537 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5538 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5540 /* Unless this is a partially-in-register argument, the argument is now
5541 in the stack.
5543 ??? Unlike the case above, in which we want the actual
5544 address of the data, so that we can load it directly into a
5545 register, here we want the address of the stack slot, so that
5546 it's properly aligned for word-by-word copying or something
5547 like that. It's not clear that this is always correct. */
5548 if (partial == 0)
5549 arg->value = arg->stack_slot;
5552 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5554 tree type = TREE_TYPE (arg->tree_value);
5555 arg->parallel_value
5556 = emit_group_load_into_temps (arg->reg, arg->value, type,
5557 int_size_in_bytes (type));
5560 /* Mark all slots this store used. */
5561 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5562 && argblock && ! variable_size && arg->stack)
5563 for (i = lower_bound; i < upper_bound; i++)
5564 stack_usage_map[i] = 1;
5566 /* Once we have pushed something, pops can't safely
5567 be deferred during the rest of the arguments. */
5568 NO_DEFER_POP;
5570 /* Free any temporary slots made in processing this argument. */
5571 pop_temp_slots ();
5573 return sibcall_failure;
5576 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5578 bool
5579 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5580 const_tree type)
5582 if (!type)
5583 return false;
5585 /* If the type has variable size... */
5586 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5587 return true;
5589 /* If the type is marked as addressable (it is required
5590 to be constructed into the stack)... */
5591 if (TREE_ADDRESSABLE (type))
5592 return true;
5594 return false;
5597 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5598 takes trailing padding of a structure into account. */
5599 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5601 bool
5602 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5604 if (!type)
5605 return false;
5607 /* If the type has variable size... */
5608 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5609 return true;
5611 /* If the type is marked as addressable (it is required
5612 to be constructed into the stack)... */
5613 if (TREE_ADDRESSABLE (type))
5614 return true;
5616 /* If the padding and mode of the type is such that a copy into
5617 a register would put it into the wrong part of the register. */
5618 if (mode == BLKmode
5619 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5620 && (targetm.calls.function_arg_padding (mode, type)
5621 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
5622 return true;
5624 return false;
5627 /* Tell the garbage collector about GTY markers in this source file. */
5628 #include "gt-calls.h"