PR ipa/69630
[official-gcc.git] / gcc / calls.c
blob8f573b83430c52955e215e7aabcdb55cb3a76d6a
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2016 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 "tm_p.h"
30 #include "stringpool.h"
31 #include "expmed.h"
32 #include "optabs.h"
33 #include "emit-rtl.h"
34 #include "cgraph.h"
35 #include "diagnostic-core.h"
36 #include "fold-const.h"
37 #include "stor-layout.h"
38 #include "varasm.h"
39 #include "internal-fn.h"
40 #include "dojump.h"
41 #include "explow.h"
42 #include "calls.h"
43 #include "expr.h"
44 #include "output.h"
45 #include "langhooks.h"
46 #include "except.h"
47 #include "dbgcnt.h"
48 #include "rtl-iter.h"
49 #include "tree-chkp.h"
50 #include "rtl-chkp.h"
53 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
54 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
56 /* Data structure and subroutines used within expand_call. */
58 struct arg_data
60 /* Tree node for this argument. */
61 tree tree_value;
62 /* Mode for value; TYPE_MODE unless promoted. */
63 machine_mode mode;
64 /* Current RTL value for argument, or 0 if it isn't precomputed. */
65 rtx value;
66 /* Initially-compute RTL value for argument; only for const functions. */
67 rtx initial_value;
68 /* Register to pass this argument in, 0 if passed on stack, or an
69 PARALLEL if the arg is to be copied into multiple non-contiguous
70 registers. */
71 rtx reg;
72 /* Register to pass this argument in when generating tail call sequence.
73 This is not the same register as for normal calls on machines with
74 register windows. */
75 rtx tail_call_reg;
76 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
77 form for emit_group_move. */
78 rtx parallel_value;
79 /* If value is passed in neither reg nor stack, this field holds a number
80 of a special slot to be used. */
81 rtx special_slot;
82 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
83 there is no such pointer. */
84 int pointer_arg;
85 /* If pointer_arg refers a structure, then pointer_offset holds an offset
86 of a pointer in this structure. */
87 int pointer_offset;
88 /* If REG was promoted from the actual mode of the argument expression,
89 indicates whether the promotion is sign- or zero-extended. */
90 int unsignedp;
91 /* Number of bytes to put in registers. 0 means put the whole arg
92 in registers. Also 0 if not passed in registers. */
93 int partial;
94 /* Nonzero if argument must be passed on stack.
95 Note that some arguments may be passed on the stack
96 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
97 pass_on_stack identifies arguments that *cannot* go in registers. */
98 int pass_on_stack;
99 /* Some fields packaged up for locate_and_pad_parm. */
100 struct locate_and_pad_arg_data locate;
101 /* Location on the stack at which parameter should be stored. The store
102 has already been done if STACK == VALUE. */
103 rtx stack;
104 /* Location on the stack of the start of this argument slot. This can
105 differ from STACK if this arg pads downward. This location is known
106 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
107 rtx stack_slot;
108 /* Place that this stack area has been saved, if needed. */
109 rtx save_area;
110 /* If an argument's alignment does not permit direct copying into registers,
111 copy in smaller-sized pieces into pseudos. These are stored in a
112 block pointed to by this field. The next field says how many
113 word-sized pseudos we made. */
114 rtx *aligned_regs;
115 int n_aligned_regs;
118 /* A vector of one char per byte of stack space. A byte if nonzero if
119 the corresponding stack location has been used.
120 This vector is used to prevent a function call within an argument from
121 clobbering any stack already set up. */
122 static char *stack_usage_map;
124 /* Size of STACK_USAGE_MAP. */
125 static int highest_outgoing_arg_in_use;
127 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
128 stack location's tail call argument has been already stored into the stack.
129 This bitmap is used to prevent sibling call optimization if function tries
130 to use parent's incoming argument slots when they have been already
131 overwritten with tail call arguments. */
132 static sbitmap stored_args_map;
134 /* stack_arg_under_construction is nonzero when an argument may be
135 initialized with a constructor call (including a C function that
136 returns a BLKmode struct) and expand_call must take special action
137 to make sure the object being constructed does not overlap the
138 argument list for the constructor call. */
139 static int stack_arg_under_construction;
141 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
142 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
143 cumulative_args_t);
144 static void precompute_register_parameters (int, struct arg_data *, int *);
145 static void store_bounds (struct arg_data *, struct arg_data *);
146 static int store_one_arg (struct arg_data *, rtx, int, int, int);
147 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
148 static int finalize_must_preallocate (int, int, struct arg_data *,
149 struct args_size *);
150 static void precompute_arguments (int, struct arg_data *);
151 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
152 static void initialize_argument_information (int, struct arg_data *,
153 struct args_size *, int,
154 tree, tree,
155 tree, tree, cumulative_args_t, int,
156 rtx *, int *, int *, int *,
157 bool *, bool);
158 static void compute_argument_addresses (struct arg_data *, rtx, int);
159 static rtx rtx_for_function_call (tree, tree);
160 static void load_register_parameters (struct arg_data *, int, rtx *, int,
161 int, int *);
162 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
163 machine_mode, int, va_list);
164 static int special_function_p (const_tree, int);
165 static int check_sibcall_argument_overlap_1 (rtx);
166 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
168 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
169 unsigned int);
170 static tree split_complex_types (tree);
172 #ifdef REG_PARM_STACK_SPACE
173 static rtx save_fixed_argument_area (int, rtx, int *, int *);
174 static void restore_fixed_argument_area (rtx, rtx, int, int);
175 #endif
177 /* Force FUNEXP into a form suitable for the address of a CALL,
178 and return that as an rtx. Also load the static chain register
179 if FNDECL is a nested function.
181 CALL_FUSAGE points to a variable holding the prospective
182 CALL_INSN_FUNCTION_USAGE information. */
185 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
186 rtx *call_fusage, int reg_parm_seen, int sibcallp)
188 /* Make a valid memory address and copy constants through pseudo-regs,
189 but not for a constant address if -fno-function-cse. */
190 if (GET_CODE (funexp) != SYMBOL_REF)
191 /* If we are using registers for parameters, force the
192 function address into a register now. */
193 funexp = ((reg_parm_seen
194 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
195 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
196 : memory_address (FUNCTION_MODE, funexp));
197 else if (! sibcallp)
199 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
200 funexp = force_reg (Pmode, funexp);
203 if (static_chain_value != 0
204 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
205 || DECL_STATIC_CHAIN (fndecl_or_type)))
207 rtx chain;
209 chain = targetm.calls.static_chain (fndecl_or_type, false);
210 static_chain_value = convert_memory_address (Pmode, static_chain_value);
212 emit_move_insn (chain, static_chain_value);
213 if (REG_P (chain))
214 use_reg (call_fusage, chain);
217 return funexp;
220 /* Generate instructions to call function FUNEXP,
221 and optionally pop the results.
222 The CALL_INSN is the first insn generated.
224 FNDECL is the declaration node of the function. This is given to the
225 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
226 its own args.
228 FUNTYPE is the data type of the function. This is given to the hook
229 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
230 own args. We used to allow an identifier for library functions, but
231 that doesn't work when the return type is an aggregate type and the
232 calling convention says that the pointer to this aggregate is to be
233 popped by the callee.
235 STACK_SIZE is the number of bytes of arguments on the stack,
236 ROUNDED_STACK_SIZE is that number rounded up to
237 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
238 both to put into the call insn and to generate explicit popping
239 code if necessary.
241 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
242 It is zero if this call doesn't want a structure value.
244 NEXT_ARG_REG is the rtx that results from executing
245 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
246 just after all the args have had their registers assigned.
247 This could be whatever you like, but normally it is the first
248 arg-register beyond those used for args in this call,
249 or 0 if all the arg-registers are used in this call.
250 It is passed on to `gen_call' so you can put this info in the call insn.
252 VALREG is a hard register in which a value is returned,
253 or 0 if the call does not return a value.
255 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
256 the args to this call were processed.
257 We restore `inhibit_defer_pop' to that value.
259 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
260 denote registers used by the called function. */
262 static void
263 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
264 tree funtype ATTRIBUTE_UNUSED,
265 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
266 HOST_WIDE_INT rounded_stack_size,
267 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
268 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
269 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
270 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
272 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
273 rtx call, funmem, pat;
274 int already_popped = 0;
275 HOST_WIDE_INT n_popped = 0;
277 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
278 patterns exist). Any popping that the callee does on return will
279 be from our caller's frame rather than ours. */
280 if (!(ecf_flags & ECF_SIBCALL))
282 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
284 #ifdef CALL_POPS_ARGS
285 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
286 #endif
289 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
290 and we don't want to load it into a register as an optimization,
291 because prepare_call_address already did it if it should be done. */
292 if (GET_CODE (funexp) != SYMBOL_REF)
293 funexp = memory_address (FUNCTION_MODE, funexp);
295 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
296 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
298 tree t = fndecl;
300 /* Although a built-in FUNCTION_DECL and its non-__builtin
301 counterpart compare equal and get a shared mem_attrs, they
302 produce different dump output in compare-debug compilations,
303 if an entry gets garbage collected in one compilation, then
304 adds a different (but equivalent) entry, while the other
305 doesn't run the garbage collector at the same spot and then
306 shares the mem_attr with the equivalent entry. */
307 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
309 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
310 if (t2)
311 t = t2;
314 set_mem_expr (funmem, t);
316 else if (fntree)
317 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
319 if (ecf_flags & ECF_SIBCALL)
321 if (valreg)
322 pat = targetm.gen_sibcall_value (valreg, funmem,
323 rounded_stack_size_rtx,
324 next_arg_reg, NULL_RTX);
325 else
326 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
327 next_arg_reg, GEN_INT (struct_value_size));
329 /* If the target has "call" or "call_value" insns, then prefer them
330 if no arguments are actually popped. If the target does not have
331 "call" or "call_value" insns, then we must use the popping versions
332 even if the call has no arguments to pop. */
333 else if (n_popped > 0
334 || !(valreg
335 ? targetm.have_call_value ()
336 : targetm.have_call ()))
338 rtx n_pop = GEN_INT (n_popped);
340 /* If this subroutine pops its own args, record that in the call insn
341 if possible, for the sake of frame pointer elimination. */
343 if (valreg)
344 pat = targetm.gen_call_value_pop (valreg, funmem,
345 rounded_stack_size_rtx,
346 next_arg_reg, n_pop);
347 else
348 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
349 next_arg_reg, n_pop);
351 already_popped = 1;
353 else
355 if (valreg)
356 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
357 next_arg_reg, NULL_RTX);
358 else
359 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
360 GEN_INT (struct_value_size));
362 emit_insn (pat);
364 /* Find the call we just emitted. */
365 rtx_call_insn *call_insn = last_call_insn ();
367 /* Some target create a fresh MEM instead of reusing the one provided
368 above. Set its MEM_EXPR. */
369 call = get_call_rtx_from (call_insn);
370 if (call
371 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
372 && MEM_EXPR (funmem) != NULL_TREE)
373 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
375 /* Mark instrumented calls. */
376 if (call && fntree)
377 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
379 /* Put the register usage information there. */
380 add_function_usage_to (call_insn, call_fusage);
382 /* If this is a const call, then set the insn's unchanging bit. */
383 if (ecf_flags & ECF_CONST)
384 RTL_CONST_CALL_P (call_insn) = 1;
386 /* If this is a pure call, then set the insn's unchanging bit. */
387 if (ecf_flags & ECF_PURE)
388 RTL_PURE_CALL_P (call_insn) = 1;
390 /* If this is a const call, then set the insn's unchanging bit. */
391 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
392 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
394 /* Create a nothrow REG_EH_REGION note, if needed. */
395 make_reg_eh_region_note (call_insn, ecf_flags, 0);
397 if (ecf_flags & ECF_NORETURN)
398 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
400 if (ecf_flags & ECF_RETURNS_TWICE)
402 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
403 cfun->calls_setjmp = 1;
406 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
408 /* Restore this now, so that we do defer pops for this call's args
409 if the context of the call as a whole permits. */
410 inhibit_defer_pop = old_inhibit_defer_pop;
412 if (n_popped > 0)
414 if (!already_popped)
415 CALL_INSN_FUNCTION_USAGE (call_insn)
416 = gen_rtx_EXPR_LIST (VOIDmode,
417 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
418 CALL_INSN_FUNCTION_USAGE (call_insn));
419 rounded_stack_size -= n_popped;
420 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
421 stack_pointer_delta -= n_popped;
423 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
425 /* If popup is needed, stack realign must use DRAP */
426 if (SUPPORTS_STACK_ALIGNMENT)
427 crtl->need_drap = true;
429 /* For noreturn calls when not accumulating outgoing args force
430 REG_ARGS_SIZE note to prevent crossjumping of calls with different
431 args sizes. */
432 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
433 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
435 if (!ACCUMULATE_OUTGOING_ARGS)
437 /* If returning from the subroutine does not automatically pop the args,
438 we need an instruction to pop them sooner or later.
439 Perhaps do it now; perhaps just record how much space to pop later.
441 If returning from the subroutine does pop the args, indicate that the
442 stack pointer will be changed. */
444 if (rounded_stack_size != 0)
446 if (ecf_flags & ECF_NORETURN)
447 /* Just pretend we did the pop. */
448 stack_pointer_delta -= rounded_stack_size;
449 else if (flag_defer_pop && inhibit_defer_pop == 0
450 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
451 pending_stack_adjust += rounded_stack_size;
452 else
453 adjust_stack (rounded_stack_size_rtx);
456 /* When we accumulate outgoing args, we must avoid any stack manipulations.
457 Restore the stack pointer to its original value now. Usually
458 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
459 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
460 popping variants of functions exist as well.
462 ??? We may optimize similar to defer_pop above, but it is
463 probably not worthwhile.
465 ??? It will be worthwhile to enable combine_stack_adjustments even for
466 such machines. */
467 else if (n_popped)
468 anti_adjust_stack (GEN_INT (n_popped));
471 /* Determine if the function identified by NAME and FNDECL is one with
472 special properties we wish to know about.
474 For example, if the function might return more than one time (setjmp), then
475 set RETURNS_TWICE to a nonzero value.
477 Similarly set NORETURN if the function is in the longjmp family.
479 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
480 space from the stack such as alloca. */
482 static int
483 special_function_p (const_tree fndecl, int flags)
485 tree name_decl = DECL_NAME (fndecl);
487 /* For instrumentation clones we want to derive flags
488 from the original name. */
489 if (cgraph_node::get (fndecl)
490 && cgraph_node::get (fndecl)->instrumentation_clone)
491 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
493 if (fndecl && name_decl
494 && IDENTIFIER_LENGTH (name_decl) <= 17
495 /* Exclude functions not at the file scope, or not `extern',
496 since they are not the magic functions we would otherwise
497 think they are.
498 FIXME: this should be handled with attributes, not with this
499 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
500 because you can declare fork() inside a function if you
501 wish. */
502 && (DECL_CONTEXT (fndecl) == NULL_TREE
503 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
504 && TREE_PUBLIC (fndecl))
506 const char *name = IDENTIFIER_POINTER (name_decl);
507 const char *tname = name;
509 /* We assume that alloca will always be called by name. It
510 makes no sense to pass it as a pointer-to-function to
511 anything that does not understand its behavior. */
512 if (IDENTIFIER_LENGTH (name_decl) == 6
513 && name[0] == 'a'
514 && ! strcmp (name, "alloca"))
515 flags |= ECF_MAY_BE_ALLOCA;
517 /* Disregard prefix _, __, __x or __builtin_. */
518 if (name[0] == '_')
520 if (name[1] == '_'
521 && name[2] == 'b'
522 && !strncmp (name + 3, "uiltin_", 7))
523 tname += 10;
524 else if (name[1] == '_' && name[2] == 'x')
525 tname += 3;
526 else if (name[1] == '_')
527 tname += 2;
528 else
529 tname += 1;
532 if (tname[0] == 's')
534 if ((tname[1] == 'e'
535 && (! strcmp (tname, "setjmp")
536 || ! strcmp (tname, "setjmp_syscall")))
537 || (tname[1] == 'i'
538 && ! strcmp (tname, "sigsetjmp"))
539 || (tname[1] == 'a'
540 && ! strcmp (tname, "savectx")))
541 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
543 if (tname[1] == 'i'
544 && ! strcmp (tname, "siglongjmp"))
545 flags |= ECF_NORETURN;
547 else if ((tname[0] == 'q' && tname[1] == 's'
548 && ! strcmp (tname, "qsetjmp"))
549 || (tname[0] == 'v' && tname[1] == 'f'
550 && ! strcmp (tname, "vfork"))
551 || (tname[0] == 'g' && tname[1] == 'e'
552 && !strcmp (tname, "getcontext")))
553 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
555 else if (tname[0] == 'l' && tname[1] == 'o'
556 && ! strcmp (tname, "longjmp"))
557 flags |= ECF_NORETURN;
560 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
561 switch (DECL_FUNCTION_CODE (fndecl))
563 case BUILT_IN_ALLOCA:
564 case BUILT_IN_ALLOCA_WITH_ALIGN:
565 flags |= ECF_MAY_BE_ALLOCA;
566 break;
567 default:
568 break;
571 return flags;
574 /* Similar to special_function_p; return a set of ERF_ flags for the
575 function FNDECL. */
576 static int
577 decl_return_flags (tree fndecl)
579 tree attr;
580 tree type = TREE_TYPE (fndecl);
581 if (!type)
582 return 0;
584 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
585 if (!attr)
586 return 0;
588 attr = TREE_VALUE (TREE_VALUE (attr));
589 if (!attr || TREE_STRING_LENGTH (attr) < 1)
590 return 0;
592 switch (TREE_STRING_POINTER (attr)[0])
594 case '1':
595 case '2':
596 case '3':
597 case '4':
598 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
600 case 'm':
601 return ERF_NOALIAS;
603 case '.':
604 default:
605 return 0;
609 /* Return nonzero when FNDECL represents a call to setjmp. */
612 setjmp_call_p (const_tree fndecl)
614 if (DECL_IS_RETURNS_TWICE (fndecl))
615 return ECF_RETURNS_TWICE;
616 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
620 /* Return true if STMT is an alloca call. */
622 bool
623 gimple_alloca_call_p (const gimple *stmt)
625 tree fndecl;
627 if (!is_gimple_call (stmt))
628 return false;
630 fndecl = gimple_call_fndecl (stmt);
631 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
632 return true;
634 return false;
637 /* Return true when exp contains alloca call. */
639 bool
640 alloca_call_p (const_tree exp)
642 tree fndecl;
643 if (TREE_CODE (exp) == CALL_EXPR
644 && (fndecl = get_callee_fndecl (exp))
645 && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
646 return true;
647 return false;
650 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
651 function. Return FALSE otherwise. */
653 static bool
654 is_tm_builtin (const_tree fndecl)
656 if (fndecl == NULL)
657 return false;
659 if (decl_is_tm_clone (fndecl))
660 return true;
662 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
664 switch (DECL_FUNCTION_CODE (fndecl))
666 case BUILT_IN_TM_COMMIT:
667 case BUILT_IN_TM_COMMIT_EH:
668 case BUILT_IN_TM_ABORT:
669 case BUILT_IN_TM_IRREVOCABLE:
670 case BUILT_IN_TM_GETTMCLONE_IRR:
671 case BUILT_IN_TM_MEMCPY:
672 case BUILT_IN_TM_MEMMOVE:
673 case BUILT_IN_TM_MEMSET:
674 CASE_BUILT_IN_TM_STORE (1):
675 CASE_BUILT_IN_TM_STORE (2):
676 CASE_BUILT_IN_TM_STORE (4):
677 CASE_BUILT_IN_TM_STORE (8):
678 CASE_BUILT_IN_TM_STORE (FLOAT):
679 CASE_BUILT_IN_TM_STORE (DOUBLE):
680 CASE_BUILT_IN_TM_STORE (LDOUBLE):
681 CASE_BUILT_IN_TM_STORE (M64):
682 CASE_BUILT_IN_TM_STORE (M128):
683 CASE_BUILT_IN_TM_STORE (M256):
684 CASE_BUILT_IN_TM_LOAD (1):
685 CASE_BUILT_IN_TM_LOAD (2):
686 CASE_BUILT_IN_TM_LOAD (4):
687 CASE_BUILT_IN_TM_LOAD (8):
688 CASE_BUILT_IN_TM_LOAD (FLOAT):
689 CASE_BUILT_IN_TM_LOAD (DOUBLE):
690 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
691 CASE_BUILT_IN_TM_LOAD (M64):
692 CASE_BUILT_IN_TM_LOAD (M128):
693 CASE_BUILT_IN_TM_LOAD (M256):
694 case BUILT_IN_TM_LOG:
695 case BUILT_IN_TM_LOG_1:
696 case BUILT_IN_TM_LOG_2:
697 case BUILT_IN_TM_LOG_4:
698 case BUILT_IN_TM_LOG_8:
699 case BUILT_IN_TM_LOG_FLOAT:
700 case BUILT_IN_TM_LOG_DOUBLE:
701 case BUILT_IN_TM_LOG_LDOUBLE:
702 case BUILT_IN_TM_LOG_M64:
703 case BUILT_IN_TM_LOG_M128:
704 case BUILT_IN_TM_LOG_M256:
705 return true;
706 default:
707 break;
710 return false;
713 /* Detect flags (function attributes) from the function decl or type node. */
716 flags_from_decl_or_type (const_tree exp)
718 int flags = 0;
720 if (DECL_P (exp))
722 /* The function exp may have the `malloc' attribute. */
723 if (DECL_IS_MALLOC (exp))
724 flags |= ECF_MALLOC;
726 /* The function exp may have the `returns_twice' attribute. */
727 if (DECL_IS_RETURNS_TWICE (exp))
728 flags |= ECF_RETURNS_TWICE;
730 /* Process the pure and const attributes. */
731 if (TREE_READONLY (exp))
732 flags |= ECF_CONST;
733 if (DECL_PURE_P (exp))
734 flags |= ECF_PURE;
735 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
736 flags |= ECF_LOOPING_CONST_OR_PURE;
738 if (DECL_IS_NOVOPS (exp))
739 flags |= ECF_NOVOPS;
740 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
741 flags |= ECF_LEAF;
743 if (TREE_NOTHROW (exp))
744 flags |= ECF_NOTHROW;
746 if (flag_tm)
748 if (is_tm_builtin (exp))
749 flags |= ECF_TM_BUILTIN;
750 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
751 || lookup_attribute ("transaction_pure",
752 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
753 flags |= ECF_TM_PURE;
756 flags = special_function_p (exp, flags);
758 else if (TYPE_P (exp))
760 if (TYPE_READONLY (exp))
761 flags |= ECF_CONST;
763 if (flag_tm
764 && ((flags & ECF_CONST) != 0
765 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
766 flags |= ECF_TM_PURE;
768 else
769 gcc_unreachable ();
771 if (TREE_THIS_VOLATILE (exp))
773 flags |= ECF_NORETURN;
774 if (flags & (ECF_CONST|ECF_PURE))
775 flags |= ECF_LOOPING_CONST_OR_PURE;
778 return flags;
781 /* Detect flags from a CALL_EXPR. */
784 call_expr_flags (const_tree t)
786 int flags;
787 tree decl = get_callee_fndecl (t);
789 if (decl)
790 flags = flags_from_decl_or_type (decl);
791 else if (CALL_EXPR_FN (t) == NULL_TREE)
792 flags = internal_fn_flags (CALL_EXPR_IFN (t));
793 else
795 t = TREE_TYPE (CALL_EXPR_FN (t));
796 if (t && TREE_CODE (t) == POINTER_TYPE)
797 flags = flags_from_decl_or_type (TREE_TYPE (t));
798 else
799 flags = 0;
802 return flags;
805 /* Return true if TYPE should be passed by invisible reference. */
807 bool
808 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
809 tree type, bool named_arg)
811 if (type)
813 /* If this type contains non-trivial constructors, then it is
814 forbidden for the middle-end to create any new copies. */
815 if (TREE_ADDRESSABLE (type))
816 return true;
818 /* GCC post 3.4 passes *all* variable sized types by reference. */
819 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
820 return true;
822 /* If a record type should be passed the same as its first (and only)
823 member, use the type and mode of that member. */
824 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
826 type = TREE_TYPE (first_field (type));
827 mode = TYPE_MODE (type);
831 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
832 type, named_arg);
835 /* Return true if TYPE, which is passed by reference, should be callee
836 copied instead of caller copied. */
838 bool
839 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
840 tree type, bool named_arg)
842 if (type && TREE_ADDRESSABLE (type))
843 return false;
844 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
845 named_arg);
849 /* Precompute all register parameters as described by ARGS, storing values
850 into fields within the ARGS array.
852 NUM_ACTUALS indicates the total number elements in the ARGS array.
854 Set REG_PARM_SEEN if we encounter a register parameter. */
856 static void
857 precompute_register_parameters (int num_actuals, struct arg_data *args,
858 int *reg_parm_seen)
860 int i;
862 *reg_parm_seen = 0;
864 for (i = 0; i < num_actuals; i++)
865 if (args[i].reg != 0 && ! args[i].pass_on_stack)
867 *reg_parm_seen = 1;
869 if (args[i].value == 0)
871 push_temp_slots ();
872 args[i].value = expand_normal (args[i].tree_value);
873 preserve_temp_slots (args[i].value);
874 pop_temp_slots ();
877 /* If we are to promote the function arg to a wider mode,
878 do it now. */
880 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
881 args[i].value
882 = convert_modes (args[i].mode,
883 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
884 args[i].value, args[i].unsignedp);
886 /* If the value is a non-legitimate constant, force it into a
887 pseudo now. TLS symbols sometimes need a call to resolve. */
888 if (CONSTANT_P (args[i].value)
889 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
890 args[i].value = force_reg (args[i].mode, args[i].value);
892 /* If we're going to have to load the value by parts, pull the
893 parts into pseudos. The part extraction process can involve
894 non-trivial computation. */
895 if (GET_CODE (args[i].reg) == PARALLEL)
897 tree type = TREE_TYPE (args[i].tree_value);
898 args[i].parallel_value
899 = emit_group_load_into_temps (args[i].reg, args[i].value,
900 type, int_size_in_bytes (type));
903 /* If the value is expensive, and we are inside an appropriately
904 short loop, put the value into a pseudo and then put the pseudo
905 into the hard reg.
907 For small register classes, also do this if this call uses
908 register parameters. This is to avoid reload conflicts while
909 loading the parameters registers. */
911 else if ((! (REG_P (args[i].value)
912 || (GET_CODE (args[i].value) == SUBREG
913 && REG_P (SUBREG_REG (args[i].value)))))
914 && args[i].mode != BLKmode
915 && (set_src_cost (args[i].value, args[i].mode,
916 optimize_insn_for_speed_p ())
917 > COSTS_N_INSNS (1))
918 && ((*reg_parm_seen
919 && targetm.small_register_classes_for_mode_p (args[i].mode))
920 || optimize))
921 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
925 #ifdef REG_PARM_STACK_SPACE
927 /* The argument list is the property of the called routine and it
928 may clobber it. If the fixed area has been used for previous
929 parameters, we must save and restore it. */
931 static rtx
932 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
934 int low;
935 int high;
937 /* Compute the boundary of the area that needs to be saved, if any. */
938 high = reg_parm_stack_space;
939 if (ARGS_GROW_DOWNWARD)
940 high += 1;
942 if (high > highest_outgoing_arg_in_use)
943 high = highest_outgoing_arg_in_use;
945 for (low = 0; low < high; low++)
946 if (stack_usage_map[low] != 0)
948 int num_to_save;
949 machine_mode save_mode;
950 int delta;
951 rtx addr;
952 rtx stack_area;
953 rtx save_area;
955 while (stack_usage_map[--high] == 0)
958 *low_to_save = low;
959 *high_to_save = high;
961 num_to_save = high - low + 1;
962 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
964 /* If we don't have the required alignment, must do this
965 in BLKmode. */
966 if ((low & (MIN (GET_MODE_SIZE (save_mode),
967 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
968 save_mode = BLKmode;
970 if (ARGS_GROW_DOWNWARD)
971 delta = -high;
972 else
973 delta = low;
975 addr = plus_constant (Pmode, argblock, delta);
976 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
978 set_mem_align (stack_area, PARM_BOUNDARY);
979 if (save_mode == BLKmode)
981 save_area = assign_stack_temp (BLKmode, num_to_save);
982 emit_block_move (validize_mem (save_area), stack_area,
983 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
985 else
987 save_area = gen_reg_rtx (save_mode);
988 emit_move_insn (save_area, stack_area);
991 return save_area;
994 return NULL_RTX;
997 static void
998 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1000 machine_mode save_mode = GET_MODE (save_area);
1001 int delta;
1002 rtx addr, stack_area;
1004 if (ARGS_GROW_DOWNWARD)
1005 delta = -high_to_save;
1006 else
1007 delta = low_to_save;
1009 addr = plus_constant (Pmode, argblock, delta);
1010 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1011 set_mem_align (stack_area, PARM_BOUNDARY);
1013 if (save_mode != BLKmode)
1014 emit_move_insn (stack_area, save_area);
1015 else
1016 emit_block_move (stack_area, validize_mem (save_area),
1017 GEN_INT (high_to_save - low_to_save + 1),
1018 BLOCK_OP_CALL_PARM);
1020 #endif /* REG_PARM_STACK_SPACE */
1022 /* If any elements in ARGS refer to parameters that are to be passed in
1023 registers, but not in memory, and whose alignment does not permit a
1024 direct copy into registers. Copy the values into a group of pseudos
1025 which we will later copy into the appropriate hard registers.
1027 Pseudos for each unaligned argument will be stored into the array
1028 args[argnum].aligned_regs. The caller is responsible for deallocating
1029 the aligned_regs array if it is nonzero. */
1031 static void
1032 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1034 int i, j;
1036 for (i = 0; i < num_actuals; i++)
1037 if (args[i].reg != 0 && ! args[i].pass_on_stack
1038 && GET_CODE (args[i].reg) != PARALLEL
1039 && args[i].mode == BLKmode
1040 && MEM_P (args[i].value)
1041 && (MEM_ALIGN (args[i].value)
1042 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1044 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1045 int endian_correction = 0;
1047 if (args[i].partial)
1049 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1050 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1052 else
1054 args[i].n_aligned_regs
1055 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1058 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1060 /* Structures smaller than a word are normally aligned to the
1061 least significant byte. On a BYTES_BIG_ENDIAN machine,
1062 this means we must skip the empty high order bytes when
1063 calculating the bit offset. */
1064 if (bytes < UNITS_PER_WORD
1065 #ifdef BLOCK_REG_PADDING
1066 && (BLOCK_REG_PADDING (args[i].mode,
1067 TREE_TYPE (args[i].tree_value), 1)
1068 == downward)
1069 #else
1070 && BYTES_BIG_ENDIAN
1071 #endif
1073 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1075 for (j = 0; j < args[i].n_aligned_regs; j++)
1077 rtx reg = gen_reg_rtx (word_mode);
1078 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1079 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1081 args[i].aligned_regs[j] = reg;
1082 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1083 word_mode, word_mode, false);
1085 /* There is no need to restrict this code to loading items
1086 in TYPE_ALIGN sized hunks. The bitfield instructions can
1087 load up entire word sized registers efficiently.
1089 ??? This may not be needed anymore.
1090 We use to emit a clobber here but that doesn't let later
1091 passes optimize the instructions we emit. By storing 0 into
1092 the register later passes know the first AND to zero out the
1093 bitfield being set in the register is unnecessary. The store
1094 of 0 will be deleted as will at least the first AND. */
1096 emit_move_insn (reg, const0_rtx);
1098 bytes -= bitsize / BITS_PER_UNIT;
1099 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1100 word_mode, word, false);
1105 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1106 CALL_EXPR EXP.
1108 NUM_ACTUALS is the total number of parameters.
1110 N_NAMED_ARGS is the total number of named arguments.
1112 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1113 value, or null.
1115 FNDECL is the tree code for the target of this call (if known)
1117 ARGS_SO_FAR holds state needed by the target to know where to place
1118 the next argument.
1120 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1121 for arguments which are passed in registers.
1123 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1124 and may be modified by this routine.
1126 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1127 flags which may be modified by this routine.
1129 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1130 that requires allocation of stack space.
1132 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1133 the thunked-to function. */
1135 static void
1136 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1137 struct arg_data *args,
1138 struct args_size *args_size,
1139 int n_named_args ATTRIBUTE_UNUSED,
1140 tree exp, tree struct_value_addr_value,
1141 tree fndecl, tree fntype,
1142 cumulative_args_t args_so_far,
1143 int reg_parm_stack_space,
1144 rtx *old_stack_level, int *old_pending_adj,
1145 int *must_preallocate, int *ecf_flags,
1146 bool *may_tailcall, bool call_from_thunk_p)
1148 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1149 location_t loc = EXPR_LOCATION (exp);
1151 /* Count arg position in order args appear. */
1152 int argpos;
1154 int i;
1156 args_size->constant = 0;
1157 args_size->var = 0;
1159 bitmap_obstack_initialize (NULL);
1161 /* In this loop, we consider args in the order they are written.
1162 We fill up ARGS from the back. */
1164 i = num_actuals - 1;
1166 int j = i, ptr_arg = -1;
1167 call_expr_arg_iterator iter;
1168 tree arg;
1169 bitmap slots = NULL;
1171 if (struct_value_addr_value)
1173 args[j].tree_value = struct_value_addr_value;
1174 j--;
1176 /* If we pass structure address then we need to
1177 create bounds for it. Since created bounds is
1178 a call statement, we expand it right here to avoid
1179 fixing all other places where it may be expanded. */
1180 if (CALL_WITH_BOUNDS_P (exp))
1182 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1183 args[j].tree_value
1184 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1185 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1186 EXPAND_NORMAL, 0, false);
1187 args[j].pointer_arg = j + 1;
1188 j--;
1191 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1193 tree argtype = TREE_TYPE (arg);
1195 /* Remember last param with pointer and associate it
1196 with following pointer bounds. */
1197 if (CALL_WITH_BOUNDS_P (exp)
1198 && chkp_type_has_pointer (argtype))
1200 if (slots)
1201 BITMAP_FREE (slots);
1202 ptr_arg = j;
1203 if (!BOUNDED_TYPE_P (argtype))
1205 slots = BITMAP_ALLOC (NULL);
1206 chkp_find_bound_slots (argtype, slots);
1209 else if (POINTER_BOUNDS_TYPE_P (argtype))
1211 /* We expect bounds in instrumented calls only.
1212 Otherwise it is a sign we lost flag due to some optimization
1213 and may emit call args incorrectly. */
1214 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1216 /* For structures look for the next available pointer. */
1217 if (ptr_arg != -1 && slots)
1219 unsigned bnd_no = bitmap_first_set_bit (slots);
1220 args[j].pointer_offset =
1221 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1223 bitmap_clear_bit (slots, bnd_no);
1225 /* Check we have no more pointers in the structure. */
1226 if (bitmap_empty_p (slots))
1227 BITMAP_FREE (slots);
1229 args[j].pointer_arg = ptr_arg;
1231 /* Check we covered all pointers in the previous
1232 non bounds arg. */
1233 if (!slots)
1234 ptr_arg = -1;
1236 else
1237 ptr_arg = -1;
1239 if (targetm.calls.split_complex_arg
1240 && argtype
1241 && TREE_CODE (argtype) == COMPLEX_TYPE
1242 && targetm.calls.split_complex_arg (argtype))
1244 tree subtype = TREE_TYPE (argtype);
1245 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1246 j--;
1247 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1249 else
1250 args[j].tree_value = arg;
1251 j--;
1254 if (slots)
1255 BITMAP_FREE (slots);
1258 bitmap_obstack_release (NULL);
1260 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1261 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1263 tree type = TREE_TYPE (args[i].tree_value);
1264 int unsignedp;
1265 machine_mode mode;
1267 /* Replace erroneous argument with constant zero. */
1268 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1269 args[i].tree_value = integer_zero_node, type = integer_type_node;
1271 /* If TYPE is a transparent union or record, pass things the way
1272 we would pass the first field of the union or record. We have
1273 already verified that the modes are the same. */
1274 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1275 && TYPE_TRANSPARENT_AGGR (type))
1276 type = TREE_TYPE (first_field (type));
1278 /* Decide where to pass this arg.
1280 args[i].reg is nonzero if all or part is passed in registers.
1282 args[i].partial is nonzero if part but not all is passed in registers,
1283 and the exact value says how many bytes are passed in registers.
1285 args[i].pass_on_stack is nonzero if the argument must at least be
1286 computed on the stack. It may then be loaded back into registers
1287 if args[i].reg is nonzero.
1289 These decisions are driven by the FUNCTION_... macros and must agree
1290 with those made by function.c. */
1292 /* See if this argument should be passed by invisible reference. */
1293 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1294 type, argpos < n_named_args))
1296 bool callee_copies;
1297 tree base = NULL_TREE;
1299 callee_copies
1300 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1301 type, argpos < n_named_args);
1303 /* If we're compiling a thunk, pass through invisible references
1304 instead of making a copy. */
1305 if (call_from_thunk_p
1306 || (callee_copies
1307 && !TREE_ADDRESSABLE (type)
1308 && (base = get_base_address (args[i].tree_value))
1309 && TREE_CODE (base) != SSA_NAME
1310 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1312 /* We may have turned the parameter value into an SSA name.
1313 Go back to the original parameter so we can take the
1314 address. */
1315 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1317 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1318 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1319 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1321 /* Argument setup code may have copied the value to register. We
1322 revert that optimization now because the tail call code must
1323 use the original location. */
1324 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1325 && !MEM_P (DECL_RTL (args[i].tree_value))
1326 && DECL_INCOMING_RTL (args[i].tree_value)
1327 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1328 set_decl_rtl (args[i].tree_value,
1329 DECL_INCOMING_RTL (args[i].tree_value));
1331 mark_addressable (args[i].tree_value);
1333 /* We can't use sibcalls if a callee-copied argument is
1334 stored in the current function's frame. */
1335 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1336 *may_tailcall = false;
1338 args[i].tree_value = build_fold_addr_expr_loc (loc,
1339 args[i].tree_value);
1340 type = TREE_TYPE (args[i].tree_value);
1342 if (*ecf_flags & ECF_CONST)
1343 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1345 else
1347 /* We make a copy of the object and pass the address to the
1348 function being called. */
1349 rtx copy;
1351 if (!COMPLETE_TYPE_P (type)
1352 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1353 || (flag_stack_check == GENERIC_STACK_CHECK
1354 && compare_tree_int (TYPE_SIZE_UNIT (type),
1355 STACK_CHECK_MAX_VAR_SIZE) > 0))
1357 /* This is a variable-sized object. Make space on the stack
1358 for it. */
1359 rtx size_rtx = expr_size (args[i].tree_value);
1361 if (*old_stack_level == 0)
1363 emit_stack_save (SAVE_BLOCK, old_stack_level);
1364 *old_pending_adj = pending_stack_adjust;
1365 pending_stack_adjust = 0;
1368 /* We can pass TRUE as the 4th argument because we just
1369 saved the stack pointer and will restore it right after
1370 the call. */
1371 copy = allocate_dynamic_stack_space (size_rtx,
1372 TYPE_ALIGN (type),
1373 TYPE_ALIGN (type),
1374 true);
1375 copy = gen_rtx_MEM (BLKmode, copy);
1376 set_mem_attributes (copy, type, 1);
1378 else
1379 copy = assign_temp (type, 1, 0);
1381 store_expr (args[i].tree_value, copy, 0, false, false);
1383 /* Just change the const function to pure and then let
1384 the next test clear the pure based on
1385 callee_copies. */
1386 if (*ecf_flags & ECF_CONST)
1388 *ecf_flags &= ~ECF_CONST;
1389 *ecf_flags |= ECF_PURE;
1392 if (!callee_copies && *ecf_flags & ECF_PURE)
1393 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1395 args[i].tree_value
1396 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1397 type = TREE_TYPE (args[i].tree_value);
1398 *may_tailcall = false;
1402 unsignedp = TYPE_UNSIGNED (type);
1403 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1404 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1406 args[i].unsignedp = unsignedp;
1407 args[i].mode = mode;
1409 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1410 argpos < n_named_args);
1412 if (args[i].reg && CONST_INT_P (args[i].reg))
1414 args[i].special_slot = args[i].reg;
1415 args[i].reg = NULL;
1418 /* If this is a sibling call and the machine has register windows, the
1419 register window has to be unwinded before calling the routine, so
1420 arguments have to go into the incoming registers. */
1421 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1422 args[i].tail_call_reg
1423 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1424 argpos < n_named_args);
1425 else
1426 args[i].tail_call_reg = args[i].reg;
1428 if (args[i].reg)
1429 args[i].partial
1430 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1431 argpos < n_named_args);
1433 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1435 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1436 it means that we are to pass this arg in the register(s) designated
1437 by the PARALLEL, but also to pass it in the stack. */
1438 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1439 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1440 args[i].pass_on_stack = 1;
1442 /* If this is an addressable type, we must preallocate the stack
1443 since we must evaluate the object into its final location.
1445 If this is to be passed in both registers and the stack, it is simpler
1446 to preallocate. */
1447 if (TREE_ADDRESSABLE (type)
1448 || (args[i].pass_on_stack && args[i].reg != 0))
1449 *must_preallocate = 1;
1451 /* No stack allocation and padding for bounds. */
1452 if (POINTER_BOUNDS_P (args[i].tree_value))
1454 /* Compute the stack-size of this argument. */
1455 else if (args[i].reg == 0 || args[i].partial != 0
1456 || reg_parm_stack_space > 0
1457 || args[i].pass_on_stack)
1458 locate_and_pad_parm (mode, type,
1459 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1461 #else
1462 args[i].reg != 0,
1463 #endif
1464 reg_parm_stack_space,
1465 args[i].pass_on_stack ? 0 : args[i].partial,
1466 fndecl, args_size, &args[i].locate);
1467 #ifdef BLOCK_REG_PADDING
1468 else
1469 /* The argument is passed entirely in registers. See at which
1470 end it should be padded. */
1471 args[i].locate.where_pad =
1472 BLOCK_REG_PADDING (mode, type,
1473 int_size_in_bytes (type) <= UNITS_PER_WORD);
1474 #endif
1476 /* Update ARGS_SIZE, the total stack space for args so far. */
1478 args_size->constant += args[i].locate.size.constant;
1479 if (args[i].locate.size.var)
1480 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1482 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1483 have been used, etc. */
1485 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1486 type, argpos < n_named_args);
1490 /* Update ARGS_SIZE to contain the total size for the argument block.
1491 Return the original constant component of the argument block's size.
1493 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1494 for arguments passed in registers. */
1496 static int
1497 compute_argument_block_size (int reg_parm_stack_space,
1498 struct args_size *args_size,
1499 tree fndecl ATTRIBUTE_UNUSED,
1500 tree fntype ATTRIBUTE_UNUSED,
1501 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1503 int unadjusted_args_size = args_size->constant;
1505 /* For accumulate outgoing args mode we don't need to align, since the frame
1506 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1507 backends from generating misaligned frame sizes. */
1508 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1509 preferred_stack_boundary = STACK_BOUNDARY;
1511 /* Compute the actual size of the argument block required. The variable
1512 and constant sizes must be combined, the size may have to be rounded,
1513 and there may be a minimum required size. */
1515 if (args_size->var)
1517 args_size->var = ARGS_SIZE_TREE (*args_size);
1518 args_size->constant = 0;
1520 preferred_stack_boundary /= BITS_PER_UNIT;
1521 if (preferred_stack_boundary > 1)
1523 /* We don't handle this case yet. To handle it correctly we have
1524 to add the delta, round and subtract the delta.
1525 Currently no machine description requires this support. */
1526 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1527 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1530 if (reg_parm_stack_space > 0)
1532 args_size->var
1533 = size_binop (MAX_EXPR, args_size->var,
1534 ssize_int (reg_parm_stack_space));
1536 /* The area corresponding to register parameters is not to count in
1537 the size of the block we need. So make the adjustment. */
1538 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1539 args_size->var
1540 = size_binop (MINUS_EXPR, args_size->var,
1541 ssize_int (reg_parm_stack_space));
1544 else
1546 preferred_stack_boundary /= BITS_PER_UNIT;
1547 if (preferred_stack_boundary < 1)
1548 preferred_stack_boundary = 1;
1549 args_size->constant = (((args_size->constant
1550 + stack_pointer_delta
1551 + preferred_stack_boundary - 1)
1552 / preferred_stack_boundary
1553 * preferred_stack_boundary)
1554 - stack_pointer_delta);
1556 args_size->constant = MAX (args_size->constant,
1557 reg_parm_stack_space);
1559 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1560 args_size->constant -= reg_parm_stack_space;
1562 return unadjusted_args_size;
1565 /* Precompute parameters as needed for a function call.
1567 FLAGS is mask of ECF_* constants.
1569 NUM_ACTUALS is the number of arguments.
1571 ARGS is an array containing information for each argument; this
1572 routine fills in the INITIAL_VALUE and VALUE fields for each
1573 precomputed argument. */
1575 static void
1576 precompute_arguments (int num_actuals, struct arg_data *args)
1578 int i;
1580 /* If this is a libcall, then precompute all arguments so that we do not
1581 get extraneous instructions emitted as part of the libcall sequence. */
1583 /* If we preallocated the stack space, and some arguments must be passed
1584 on the stack, then we must precompute any parameter which contains a
1585 function call which will store arguments on the stack.
1586 Otherwise, evaluating the parameter may clobber previous parameters
1587 which have already been stored into the stack. (we have code to avoid
1588 such case by saving the outgoing stack arguments, but it results in
1589 worse code) */
1590 if (!ACCUMULATE_OUTGOING_ARGS)
1591 return;
1593 for (i = 0; i < num_actuals; i++)
1595 tree type;
1596 machine_mode mode;
1598 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1599 continue;
1601 /* If this is an addressable type, we cannot pre-evaluate it. */
1602 type = TREE_TYPE (args[i].tree_value);
1603 gcc_assert (!TREE_ADDRESSABLE (type));
1605 args[i].initial_value = args[i].value
1606 = expand_normal (args[i].tree_value);
1608 mode = TYPE_MODE (type);
1609 if (mode != args[i].mode)
1611 int unsignedp = args[i].unsignedp;
1612 args[i].value
1613 = convert_modes (args[i].mode, mode,
1614 args[i].value, args[i].unsignedp);
1616 /* CSE will replace this only if it contains args[i].value
1617 pseudo, so convert it down to the declared mode using
1618 a SUBREG. */
1619 if (REG_P (args[i].value)
1620 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1621 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1623 args[i].initial_value
1624 = gen_lowpart_SUBREG (mode, args[i].value);
1625 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1626 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
1632 /* Given the current state of MUST_PREALLOCATE and information about
1633 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1634 compute and return the final value for MUST_PREALLOCATE. */
1636 static int
1637 finalize_must_preallocate (int must_preallocate, int num_actuals,
1638 struct arg_data *args, struct args_size *args_size)
1640 /* See if we have or want to preallocate stack space.
1642 If we would have to push a partially-in-regs parm
1643 before other stack parms, preallocate stack space instead.
1645 If the size of some parm is not a multiple of the required stack
1646 alignment, we must preallocate.
1648 If the total size of arguments that would otherwise create a copy in
1649 a temporary (such as a CALL) is more than half the total argument list
1650 size, preallocation is faster.
1652 Another reason to preallocate is if we have a machine (like the m88k)
1653 where stack alignment is required to be maintained between every
1654 pair of insns, not just when the call is made. However, we assume here
1655 that such machines either do not have push insns (and hence preallocation
1656 would occur anyway) or the problem is taken care of with
1657 PUSH_ROUNDING. */
1659 if (! must_preallocate)
1661 int partial_seen = 0;
1662 int copy_to_evaluate_size = 0;
1663 int i;
1665 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1667 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1668 partial_seen = 1;
1669 else if (partial_seen && args[i].reg == 0)
1670 must_preallocate = 1;
1671 /* We preallocate in case there are bounds passed
1672 in the bounds table to have precomputed address
1673 for bounds association. */
1674 else if (POINTER_BOUNDS_P (args[i].tree_value)
1675 && !args[i].reg)
1676 must_preallocate = 1;
1678 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1679 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1680 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1681 || TREE_CODE (args[i].tree_value) == COND_EXPR
1682 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1683 copy_to_evaluate_size
1684 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1687 if (copy_to_evaluate_size * 2 >= args_size->constant
1688 && args_size->constant > 0)
1689 must_preallocate = 1;
1691 return must_preallocate;
1694 /* If we preallocated stack space, compute the address of each argument
1695 and store it into the ARGS array.
1697 We need not ensure it is a valid memory address here; it will be
1698 validized when it is used.
1700 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1702 static void
1703 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1705 if (argblock)
1707 rtx arg_reg = argblock;
1708 int i, arg_offset = 0;
1710 if (GET_CODE (argblock) == PLUS)
1711 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1713 for (i = 0; i < num_actuals; i++)
1715 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1716 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1717 rtx addr;
1718 unsigned int align, boundary;
1719 unsigned int units_on_stack = 0;
1720 machine_mode partial_mode = VOIDmode;
1722 /* Skip this parm if it will not be passed on the stack. */
1723 if (! args[i].pass_on_stack
1724 && args[i].reg != 0
1725 && args[i].partial == 0)
1726 continue;
1728 /* Pointer Bounds are never passed on the stack. */
1729 if (POINTER_BOUNDS_P (args[i].tree_value))
1730 continue;
1732 if (CONST_INT_P (offset))
1733 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
1734 else
1735 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1737 addr = plus_constant (Pmode, addr, arg_offset);
1739 if (args[i].partial != 0)
1741 /* Only part of the parameter is being passed on the stack.
1742 Generate a simple memory reference of the correct size. */
1743 units_on_stack = args[i].locate.size.constant;
1744 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1745 MODE_INT, 1);
1746 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1747 set_mem_size (args[i].stack, units_on_stack);
1749 else
1751 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1752 set_mem_attributes (args[i].stack,
1753 TREE_TYPE (args[i].tree_value), 1);
1755 align = BITS_PER_UNIT;
1756 boundary = args[i].locate.boundary;
1757 if (args[i].locate.where_pad != downward)
1758 align = boundary;
1759 else if (CONST_INT_P (offset))
1761 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1762 align = align & -align;
1764 set_mem_align (args[i].stack, align);
1766 if (CONST_INT_P (slot_offset))
1767 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
1768 else
1769 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1771 addr = plus_constant (Pmode, addr, arg_offset);
1773 if (args[i].partial != 0)
1775 /* Only part of the parameter is being passed on the stack.
1776 Generate a simple memory reference of the correct size.
1778 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1779 set_mem_size (args[i].stack_slot, units_on_stack);
1781 else
1783 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1784 set_mem_attributes (args[i].stack_slot,
1785 TREE_TYPE (args[i].tree_value), 1);
1787 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1789 /* Function incoming arguments may overlap with sibling call
1790 outgoing arguments and we cannot allow reordering of reads
1791 from function arguments with stores to outgoing arguments
1792 of sibling calls. */
1793 set_mem_alias_set (args[i].stack, 0);
1794 set_mem_alias_set (args[i].stack_slot, 0);
1799 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1800 in a call instruction.
1802 FNDECL is the tree node for the target function. For an indirect call
1803 FNDECL will be NULL_TREE.
1805 ADDR is the operand 0 of CALL_EXPR for this call. */
1807 static rtx
1808 rtx_for_function_call (tree fndecl, tree addr)
1810 rtx funexp;
1812 /* Get the function to call, in the form of RTL. */
1813 if (fndecl)
1815 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1816 TREE_USED (fndecl) = 1;
1818 /* Get a SYMBOL_REF rtx for the function address. */
1819 funexp = XEXP (DECL_RTL (fndecl), 0);
1821 else
1822 /* Generate an rtx (probably a pseudo-register) for the address. */
1824 push_temp_slots ();
1825 funexp = expand_normal (addr);
1826 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1828 return funexp;
1831 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1832 static struct
1834 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1835 or NULL_RTX if none has been scanned yet. */
1836 rtx_insn *scan_start;
1837 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1838 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1839 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1840 with fixed offset, or PC if this is with variable or unknown offset. */
1841 vec<rtx> cache;
1842 } internal_arg_pointer_exp_state;
1844 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
1846 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1847 the tail call sequence, starting with first insn that hasn't been
1848 scanned yet, and note for each pseudo on the LHS whether it is based
1849 on crtl->args.internal_arg_pointer or not, and what offset from that
1850 that pointer it has. */
1852 static void
1853 internal_arg_pointer_based_exp_scan (void)
1855 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
1857 if (scan_start == NULL_RTX)
1858 insn = get_insns ();
1859 else
1860 insn = NEXT_INSN (scan_start);
1862 while (insn)
1864 rtx set = single_set (insn);
1865 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1867 rtx val = NULL_RTX;
1868 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1869 /* Punt on pseudos set multiple times. */
1870 if (idx < internal_arg_pointer_exp_state.cache.length ()
1871 && (internal_arg_pointer_exp_state.cache[idx]
1872 != NULL_RTX))
1873 val = pc_rtx;
1874 else
1875 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1876 if (val != NULL_RTX)
1878 if (idx >= internal_arg_pointer_exp_state.cache.length ())
1879 internal_arg_pointer_exp_state.cache
1880 .safe_grow_cleared (idx + 1);
1881 internal_arg_pointer_exp_state.cache[idx] = val;
1884 if (NEXT_INSN (insn) == NULL_RTX)
1885 scan_start = insn;
1886 insn = NEXT_INSN (insn);
1889 internal_arg_pointer_exp_state.scan_start = scan_start;
1892 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1893 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1894 it with fixed offset, or PC if this is with variable or unknown offset.
1895 TOPLEVEL is true if the function is invoked at the topmost level. */
1897 static rtx
1898 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
1900 if (CONSTANT_P (rtl))
1901 return NULL_RTX;
1903 if (rtl == crtl->args.internal_arg_pointer)
1904 return const0_rtx;
1906 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1907 return NULL_RTX;
1909 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1911 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1912 if (val == NULL_RTX || val == pc_rtx)
1913 return val;
1914 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
1917 /* When called at the topmost level, scan pseudo assignments in between the
1918 last scanned instruction in the tail call sequence and the latest insn
1919 in that sequence. */
1920 if (toplevel)
1921 internal_arg_pointer_based_exp_scan ();
1923 if (REG_P (rtl))
1925 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1926 if (idx < internal_arg_pointer_exp_state.cache.length ())
1927 return internal_arg_pointer_exp_state.cache[idx];
1929 return NULL_RTX;
1932 subrtx_iterator::array_type array;
1933 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
1935 const_rtx x = *iter;
1936 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
1937 return pc_rtx;
1938 if (MEM_P (x))
1939 iter.skip_subrtxes ();
1942 return NULL_RTX;
1945 /* Return true if and only if SIZE storage units (usually bytes)
1946 starting from address ADDR overlap with already clobbered argument
1947 area. This function is used to determine if we should give up a
1948 sibcall. */
1950 static bool
1951 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1953 HOST_WIDE_INT i;
1954 rtx val;
1956 if (bitmap_empty_p (stored_args_map))
1957 return false;
1958 val = internal_arg_pointer_based_exp (addr, true);
1959 if (val == NULL_RTX)
1960 return false;
1961 else if (val == pc_rtx)
1962 return true;
1963 else
1964 i = INTVAL (val);
1966 if (STACK_GROWS_DOWNWARD)
1967 i -= crtl->args.pretend_args_size;
1968 else
1969 i += crtl->args.pretend_args_size;
1972 if (ARGS_GROW_DOWNWARD)
1973 i = -i - size;
1975 if (size > 0)
1977 unsigned HOST_WIDE_INT k;
1979 for (k = 0; k < size; k++)
1980 if (i + k < SBITMAP_SIZE (stored_args_map)
1981 && bitmap_bit_p (stored_args_map, i + k))
1982 return true;
1985 return false;
1988 /* Do the register loads required for any wholly-register parms or any
1989 parms which are passed both on the stack and in a register. Their
1990 expressions were already evaluated.
1992 Mark all register-parms as living through the call, putting these USE
1993 insns in the CALL_INSN_FUNCTION_USAGE field.
1995 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1996 checking, setting *SIBCALL_FAILURE if appropriate. */
1998 static void
1999 load_register_parameters (struct arg_data *args, int num_actuals,
2000 rtx *call_fusage, int flags, int is_sibcall,
2001 int *sibcall_failure)
2003 int i, j;
2005 for (i = 0; i < num_actuals; i++)
2007 rtx reg = ((flags & ECF_SIBCALL)
2008 ? args[i].tail_call_reg : args[i].reg);
2009 if (reg)
2011 int partial = args[i].partial;
2012 int nregs;
2013 int size = 0;
2014 rtx_insn *before_arg = get_last_insn ();
2015 /* Set non-negative if we must move a word at a time, even if
2016 just one word (e.g, partial == 4 && mode == DFmode). Set
2017 to -1 if we just use a normal move insn. This value can be
2018 zero if the argument is a zero size structure. */
2019 nregs = -1;
2020 if (GET_CODE (reg) == PARALLEL)
2022 else if (partial)
2024 gcc_assert (partial % UNITS_PER_WORD == 0);
2025 nregs = partial / UNITS_PER_WORD;
2027 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2029 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2030 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2032 else
2033 size = GET_MODE_SIZE (args[i].mode);
2035 /* Handle calls that pass values in multiple non-contiguous
2036 locations. The Irix 6 ABI has examples of this. */
2038 if (GET_CODE (reg) == PARALLEL)
2039 emit_group_move (reg, args[i].parallel_value);
2041 /* If simple case, just do move. If normal partial, store_one_arg
2042 has already loaded the register for us. In all other cases,
2043 load the register(s) from memory. */
2045 else if (nregs == -1)
2047 emit_move_insn (reg, args[i].value);
2048 #ifdef BLOCK_REG_PADDING
2049 /* Handle case where we have a value that needs shifting
2050 up to the msb. eg. a QImode value and we're padding
2051 upward on a BYTES_BIG_ENDIAN machine. */
2052 if (size < UNITS_PER_WORD
2053 && (args[i].locate.where_pad
2054 == (BYTES_BIG_ENDIAN ? upward : downward)))
2056 rtx x;
2057 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2059 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2060 report the whole reg as used. Strictly speaking, the
2061 call only uses SIZE bytes at the msb end, but it doesn't
2062 seem worth generating rtl to say that. */
2063 reg = gen_rtx_REG (word_mode, REGNO (reg));
2064 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2065 if (x != reg)
2066 emit_move_insn (reg, x);
2068 #endif
2071 /* If we have pre-computed the values to put in the registers in
2072 the case of non-aligned structures, copy them in now. */
2074 else if (args[i].n_aligned_regs != 0)
2075 for (j = 0; j < args[i].n_aligned_regs; j++)
2076 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2077 args[i].aligned_regs[j]);
2079 else if (partial == 0 || args[i].pass_on_stack)
2081 rtx mem = validize_mem (copy_rtx (args[i].value));
2083 /* Check for overlap with already clobbered argument area,
2084 providing that this has non-zero size. */
2085 if (is_sibcall
2086 && (size == 0
2087 || mem_overlaps_already_clobbered_arg_p
2088 (XEXP (args[i].value, 0), size)))
2089 *sibcall_failure = 1;
2091 if (size % UNITS_PER_WORD == 0
2092 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2093 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2094 else
2096 if (nregs > 1)
2097 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2098 args[i].mode);
2099 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2100 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2101 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2102 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2103 word_mode, word_mode, false);
2104 if (BYTES_BIG_ENDIAN)
2105 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2106 BITS_PER_WORD - bitsize, dest, 1);
2107 if (x != dest)
2108 emit_move_insn (dest, x);
2111 /* Handle a BLKmode that needs shifting. */
2112 if (nregs == 1 && size < UNITS_PER_WORD
2113 #ifdef BLOCK_REG_PADDING
2114 && args[i].locate.where_pad == downward
2115 #else
2116 && BYTES_BIG_ENDIAN
2117 #endif
2120 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2121 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2122 enum tree_code dir = (BYTES_BIG_ENDIAN
2123 ? RSHIFT_EXPR : LSHIFT_EXPR);
2124 rtx x;
2126 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2127 if (x != dest)
2128 emit_move_insn (dest, x);
2132 /* When a parameter is a block, and perhaps in other cases, it is
2133 possible that it did a load from an argument slot that was
2134 already clobbered. */
2135 if (is_sibcall
2136 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2137 *sibcall_failure = 1;
2139 /* Handle calls that pass values in multiple non-contiguous
2140 locations. The Irix 6 ABI has examples of this. */
2141 if (GET_CODE (reg) == PARALLEL)
2142 use_group_regs (call_fusage, reg);
2143 else if (nregs == -1)
2144 use_reg_mode (call_fusage, reg,
2145 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2146 else if (nregs > 0)
2147 use_regs (call_fusage, REGNO (reg), nregs);
2152 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2153 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2154 bytes, then we would need to push some additional bytes to pad the
2155 arguments. So, we compute an adjust to the stack pointer for an
2156 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2157 bytes. Then, when the arguments are pushed the stack will be perfectly
2158 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2159 be popped after the call. Returns the adjustment. */
2161 static int
2162 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2163 struct args_size *args_size,
2164 unsigned int preferred_unit_stack_boundary)
2166 /* The number of bytes to pop so that the stack will be
2167 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2168 HOST_WIDE_INT adjustment;
2169 /* The alignment of the stack after the arguments are pushed, if we
2170 just pushed the arguments without adjust the stack here. */
2171 unsigned HOST_WIDE_INT unadjusted_alignment;
2173 unadjusted_alignment
2174 = ((stack_pointer_delta + unadjusted_args_size)
2175 % preferred_unit_stack_boundary);
2177 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2178 as possible -- leaving just enough left to cancel out the
2179 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2180 PENDING_STACK_ADJUST is non-negative, and congruent to
2181 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2183 /* Begin by trying to pop all the bytes. */
2184 unadjusted_alignment
2185 = (unadjusted_alignment
2186 - (pending_stack_adjust % preferred_unit_stack_boundary));
2187 adjustment = pending_stack_adjust;
2188 /* Push enough additional bytes that the stack will be aligned
2189 after the arguments are pushed. */
2190 if (preferred_unit_stack_boundary > 1)
2192 if (unadjusted_alignment > 0)
2193 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2194 else
2195 adjustment += unadjusted_alignment;
2198 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2199 bytes after the call. The right number is the entire
2200 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2201 by the arguments in the first place. */
2202 args_size->constant
2203 = pending_stack_adjust - adjustment + unadjusted_args_size;
2205 return adjustment;
2208 /* Scan X expression if it does not dereference any argument slots
2209 we already clobbered by tail call arguments (as noted in stored_args_map
2210 bitmap).
2211 Return nonzero if X expression dereferences such argument slots,
2212 zero otherwise. */
2214 static int
2215 check_sibcall_argument_overlap_1 (rtx x)
2217 RTX_CODE code;
2218 int i, j;
2219 const char *fmt;
2221 if (x == NULL_RTX)
2222 return 0;
2224 code = GET_CODE (x);
2226 /* We need not check the operands of the CALL expression itself. */
2227 if (code == CALL)
2228 return 0;
2230 if (code == MEM)
2231 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2232 GET_MODE_SIZE (GET_MODE (x)));
2234 /* Scan all subexpressions. */
2235 fmt = GET_RTX_FORMAT (code);
2236 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2238 if (*fmt == 'e')
2240 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2241 return 1;
2243 else if (*fmt == 'E')
2245 for (j = 0; j < XVECLEN (x, i); j++)
2246 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2247 return 1;
2250 return 0;
2253 /* Scan sequence after INSN if it does not dereference any argument slots
2254 we already clobbered by tail call arguments (as noted in stored_args_map
2255 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2256 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2257 should be 0). Return nonzero if sequence after INSN dereferences such argument
2258 slots, zero otherwise. */
2260 static int
2261 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2262 int mark_stored_args_map)
2264 int low, high;
2266 if (insn == NULL_RTX)
2267 insn = get_insns ();
2268 else
2269 insn = NEXT_INSN (insn);
2271 for (; insn; insn = NEXT_INSN (insn))
2272 if (INSN_P (insn)
2273 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2274 break;
2276 if (mark_stored_args_map)
2278 if (ARGS_GROW_DOWNWARD)
2279 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2280 else
2281 low = arg->locate.slot_offset.constant;
2283 for (high = low + arg->locate.size.constant; low < high; low++)
2284 bitmap_set_bit (stored_args_map, low);
2286 return insn != NULL_RTX;
2289 /* Given that a function returns a value of mode MODE at the most
2290 significant end of hard register VALUE, shift VALUE left or right
2291 as specified by LEFT_P. Return true if some action was needed. */
2293 bool
2294 shift_return_value (machine_mode mode, bool left_p, rtx value)
2296 HOST_WIDE_INT shift;
2298 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2299 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2300 if (shift == 0)
2301 return false;
2303 /* Use ashr rather than lshr for right shifts. This is for the benefit
2304 of the MIPS port, which requires SImode values to be sign-extended
2305 when stored in 64-bit registers. */
2306 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2307 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2308 gcc_unreachable ();
2309 return true;
2312 /* If X is a likely-spilled register value, copy it to a pseudo
2313 register and return that register. Return X otherwise. */
2315 static rtx
2316 avoid_likely_spilled_reg (rtx x)
2318 rtx new_rtx;
2320 if (REG_P (x)
2321 && HARD_REGISTER_P (x)
2322 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2324 /* Make sure that we generate a REG rather than a CONCAT.
2325 Moves into CONCATs can need nontrivial instructions,
2326 and the whole point of this function is to avoid
2327 using the hard register directly in such a situation. */
2328 generating_concat_p = 0;
2329 new_rtx = gen_reg_rtx (GET_MODE (x));
2330 generating_concat_p = 1;
2331 emit_move_insn (new_rtx, x);
2332 return new_rtx;
2334 return x;
2337 /* Generate all the code for a CALL_EXPR exp
2338 and return an rtx for its value.
2339 Store the value in TARGET (specified as an rtx) if convenient.
2340 If the value is stored in TARGET then TARGET is returned.
2341 If IGNORE is nonzero, then we ignore the value of the function call. */
2344 expand_call (tree exp, rtx target, int ignore)
2346 /* Nonzero if we are currently expanding a call. */
2347 static int currently_expanding_call = 0;
2349 /* RTX for the function to be called. */
2350 rtx funexp;
2351 /* Sequence of insns to perform a normal "call". */
2352 rtx_insn *normal_call_insns = NULL;
2353 /* Sequence of insns to perform a tail "call". */
2354 rtx_insn *tail_call_insns = NULL;
2355 /* Data type of the function. */
2356 tree funtype;
2357 tree type_arg_types;
2358 tree rettype;
2359 /* Declaration of the function being called,
2360 or 0 if the function is computed (not known by name). */
2361 tree fndecl = 0;
2362 /* The type of the function being called. */
2363 tree fntype;
2364 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2365 int pass;
2367 /* Register in which non-BLKmode value will be returned,
2368 or 0 if no value or if value is BLKmode. */
2369 rtx valreg;
2370 /* Register(s) in which bounds are returned. */
2371 rtx valbnd = NULL;
2372 /* Address where we should return a BLKmode value;
2373 0 if value not BLKmode. */
2374 rtx structure_value_addr = 0;
2375 /* Nonzero if that address is being passed by treating it as
2376 an extra, implicit first parameter. Otherwise,
2377 it is passed by being copied directly into struct_value_rtx. */
2378 int structure_value_addr_parm = 0;
2379 /* Holds the value of implicit argument for the struct value. */
2380 tree structure_value_addr_value = NULL_TREE;
2381 /* Size of aggregate value wanted, or zero if none wanted
2382 or if we are using the non-reentrant PCC calling convention
2383 or expecting the value in registers. */
2384 HOST_WIDE_INT struct_value_size = 0;
2385 /* Nonzero if called function returns an aggregate in memory PCC style,
2386 by returning the address of where to find it. */
2387 int pcc_struct_value = 0;
2388 rtx struct_value = 0;
2390 /* Number of actual parameters in this call, including struct value addr. */
2391 int num_actuals;
2392 /* Number of named args. Args after this are anonymous ones
2393 and they must all go on the stack. */
2394 int n_named_args;
2395 /* Number of complex actual arguments that need to be split. */
2396 int num_complex_actuals = 0;
2398 /* Vector of information about each argument.
2399 Arguments are numbered in the order they will be pushed,
2400 not the order they are written. */
2401 struct arg_data *args;
2403 /* Total size in bytes of all the stack-parms scanned so far. */
2404 struct args_size args_size;
2405 struct args_size adjusted_args_size;
2406 /* Size of arguments before any adjustments (such as rounding). */
2407 int unadjusted_args_size;
2408 /* Data on reg parms scanned so far. */
2409 CUMULATIVE_ARGS args_so_far_v;
2410 cumulative_args_t args_so_far;
2411 /* Nonzero if a reg parm has been scanned. */
2412 int reg_parm_seen;
2413 /* Nonzero if this is an indirect function call. */
2415 /* Nonzero if we must avoid push-insns in the args for this call.
2416 If stack space is allocated for register parameters, but not by the
2417 caller, then it is preallocated in the fixed part of the stack frame.
2418 So the entire argument block must then be preallocated (i.e., we
2419 ignore PUSH_ROUNDING in that case). */
2421 int must_preallocate = !PUSH_ARGS;
2423 /* Size of the stack reserved for parameter registers. */
2424 int reg_parm_stack_space = 0;
2426 /* Address of space preallocated for stack parms
2427 (on machines that lack push insns), or 0 if space not preallocated. */
2428 rtx argblock = 0;
2430 /* Mask of ECF_ and ERF_ flags. */
2431 int flags = 0;
2432 int return_flags = 0;
2433 #ifdef REG_PARM_STACK_SPACE
2434 /* Define the boundary of the register parm stack space that needs to be
2435 saved, if any. */
2436 int low_to_save, high_to_save;
2437 rtx save_area = 0; /* Place that it is saved */
2438 #endif
2440 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2441 char *initial_stack_usage_map = stack_usage_map;
2442 char *stack_usage_map_buf = NULL;
2444 int old_stack_allocated;
2446 /* State variables to track stack modifications. */
2447 rtx old_stack_level = 0;
2448 int old_stack_arg_under_construction = 0;
2449 int old_pending_adj = 0;
2450 int old_inhibit_defer_pop = inhibit_defer_pop;
2452 /* Some stack pointer alterations we make are performed via
2453 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2454 which we then also need to save/restore along the way. */
2455 int old_stack_pointer_delta = 0;
2457 rtx call_fusage;
2458 tree addr = CALL_EXPR_FN (exp);
2459 int i;
2460 /* The alignment of the stack, in bits. */
2461 unsigned HOST_WIDE_INT preferred_stack_boundary;
2462 /* The alignment of the stack, in bytes. */
2463 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2464 /* The static chain value to use for this call. */
2465 rtx static_chain_value;
2466 /* See if this is "nothrow" function call. */
2467 if (TREE_NOTHROW (exp))
2468 flags |= ECF_NOTHROW;
2470 /* See if we can find a DECL-node for the actual function, and get the
2471 function attributes (flags) from the function decl or type node. */
2472 fndecl = get_callee_fndecl (exp);
2473 if (fndecl)
2475 fntype = TREE_TYPE (fndecl);
2476 flags |= flags_from_decl_or_type (fndecl);
2477 return_flags |= decl_return_flags (fndecl);
2479 else
2481 fntype = TREE_TYPE (TREE_TYPE (addr));
2482 flags |= flags_from_decl_or_type (fntype);
2484 rettype = TREE_TYPE (exp);
2486 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2488 /* Warn if this value is an aggregate type,
2489 regardless of which calling convention we are using for it. */
2490 if (AGGREGATE_TYPE_P (rettype))
2491 warning (OPT_Waggregate_return, "function call has aggregate value");
2493 /* If the result of a non looping pure or const function call is
2494 ignored (or void), and none of its arguments are volatile, we can
2495 avoid expanding the call and just evaluate the arguments for
2496 side-effects. */
2497 if ((flags & (ECF_CONST | ECF_PURE))
2498 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2499 && (ignore || target == const0_rtx
2500 || TYPE_MODE (rettype) == VOIDmode))
2502 bool volatilep = false;
2503 tree arg;
2504 call_expr_arg_iterator iter;
2506 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2507 if (TREE_THIS_VOLATILE (arg))
2509 volatilep = true;
2510 break;
2513 if (! volatilep)
2515 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2516 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2517 return const0_rtx;
2521 #ifdef REG_PARM_STACK_SPACE
2522 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2523 #endif
2525 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2526 && reg_parm_stack_space > 0 && PUSH_ARGS)
2527 must_preallocate = 1;
2529 /* Set up a place to return a structure. */
2531 /* Cater to broken compilers. */
2532 if (aggregate_value_p (exp, fntype))
2534 /* This call returns a big structure. */
2535 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2537 #ifdef PCC_STATIC_STRUCT_RETURN
2539 pcc_struct_value = 1;
2541 #else /* not PCC_STATIC_STRUCT_RETURN */
2543 struct_value_size = int_size_in_bytes (rettype);
2545 /* Even if it is semantically safe to use the target as the return
2546 slot, it may be not sufficiently aligned for the return type. */
2547 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
2548 && target
2549 && MEM_P (target)
2550 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
2551 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
2552 MEM_ALIGN (target))))
2553 structure_value_addr = XEXP (target, 0);
2554 else
2556 /* For variable-sized objects, we must be called with a target
2557 specified. If we were to allocate space on the stack here,
2558 we would have no way of knowing when to free it. */
2559 rtx d = assign_temp (rettype, 1, 1);
2560 structure_value_addr = XEXP (d, 0);
2561 target = 0;
2564 #endif /* not PCC_STATIC_STRUCT_RETURN */
2567 /* Figure out the amount to which the stack should be aligned. */
2568 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2569 if (fndecl)
2571 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
2572 /* Without automatic stack alignment, we can't increase preferred
2573 stack boundary. With automatic stack alignment, it is
2574 unnecessary since unless we can guarantee that all callers will
2575 align the outgoing stack properly, callee has to align its
2576 stack anyway. */
2577 if (i
2578 && i->preferred_incoming_stack_boundary
2579 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2580 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2583 /* Operand 0 is a pointer-to-function; get the type of the function. */
2584 funtype = TREE_TYPE (addr);
2585 gcc_assert (POINTER_TYPE_P (funtype));
2586 funtype = TREE_TYPE (funtype);
2588 /* Count whether there are actual complex arguments that need to be split
2589 into their real and imaginary parts. Munge the type_arg_types
2590 appropriately here as well. */
2591 if (targetm.calls.split_complex_arg)
2593 call_expr_arg_iterator iter;
2594 tree arg;
2595 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2597 tree type = TREE_TYPE (arg);
2598 if (type && TREE_CODE (type) == COMPLEX_TYPE
2599 && targetm.calls.split_complex_arg (type))
2600 num_complex_actuals++;
2602 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2604 else
2605 type_arg_types = TYPE_ARG_TYPES (funtype);
2607 if (flags & ECF_MAY_BE_ALLOCA)
2608 cfun->calls_alloca = 1;
2610 /* If struct_value_rtx is 0, it means pass the address
2611 as if it were an extra parameter. Put the argument expression
2612 in structure_value_addr_value. */
2613 if (structure_value_addr && struct_value == 0)
2615 /* If structure_value_addr is a REG other than
2616 virtual_outgoing_args_rtx, we can use always use it. If it
2617 is not a REG, we must always copy it into a register.
2618 If it is virtual_outgoing_args_rtx, we must copy it to another
2619 register in some cases. */
2620 rtx temp = (!REG_P (structure_value_addr)
2621 || (ACCUMULATE_OUTGOING_ARGS
2622 && stack_arg_under_construction
2623 && structure_value_addr == virtual_outgoing_args_rtx)
2624 ? copy_addr_to_reg (convert_memory_address
2625 (Pmode, structure_value_addr))
2626 : structure_value_addr);
2628 structure_value_addr_value =
2629 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2630 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
2633 /* Count the arguments and set NUM_ACTUALS. */
2634 num_actuals =
2635 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2637 /* Compute number of named args.
2638 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2640 if (type_arg_types != 0)
2641 n_named_args
2642 = (list_length (type_arg_types)
2643 /* Count the struct value address, if it is passed as a parm. */
2644 + structure_value_addr_parm);
2645 else
2646 /* If we know nothing, treat all args as named. */
2647 n_named_args = num_actuals;
2649 /* Start updating where the next arg would go.
2651 On some machines (such as the PA) indirect calls have a different
2652 calling convention than normal calls. The fourth argument in
2653 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2654 or not. */
2655 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2656 args_so_far = pack_cumulative_args (&args_so_far_v);
2658 /* Now possibly adjust the number of named args.
2659 Normally, don't include the last named arg if anonymous args follow.
2660 We do include the last named arg if
2661 targetm.calls.strict_argument_naming() returns nonzero.
2662 (If no anonymous args follow, the result of list_length is actually
2663 one too large. This is harmless.)
2665 If targetm.calls.pretend_outgoing_varargs_named() returns
2666 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2667 this machine will be able to place unnamed args that were passed
2668 in registers into the stack. So treat all args as named. This
2669 allows the insns emitting for a specific argument list to be
2670 independent of the function declaration.
2672 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2673 we do not have any reliable way to pass unnamed args in
2674 registers, so we must force them into memory. */
2676 if (type_arg_types != 0
2677 && targetm.calls.strict_argument_naming (args_so_far))
2679 else if (type_arg_types != 0
2680 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2681 /* Don't include the last named arg. */
2682 --n_named_args;
2683 else
2684 /* Treat all args as named. */
2685 n_named_args = num_actuals;
2687 /* Make a vector to hold all the information about each arg. */
2688 args = XALLOCAVEC (struct arg_data, num_actuals);
2689 memset (args, 0, num_actuals * sizeof (struct arg_data));
2691 /* Build up entries in the ARGS array, compute the size of the
2692 arguments into ARGS_SIZE, etc. */
2693 initialize_argument_information (num_actuals, args, &args_size,
2694 n_named_args, exp,
2695 structure_value_addr_value, fndecl, fntype,
2696 args_so_far, reg_parm_stack_space,
2697 &old_stack_level, &old_pending_adj,
2698 &must_preallocate, &flags,
2699 &try_tail_call, CALL_FROM_THUNK_P (exp));
2701 if (args_size.var)
2702 must_preallocate = 1;
2704 /* Now make final decision about preallocating stack space. */
2705 must_preallocate = finalize_must_preallocate (must_preallocate,
2706 num_actuals, args,
2707 &args_size);
2709 /* If the structure value address will reference the stack pointer, we
2710 must stabilize it. We don't need to do this if we know that we are
2711 not going to adjust the stack pointer in processing this call. */
2713 if (structure_value_addr
2714 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2715 || reg_mentioned_p (virtual_outgoing_args_rtx,
2716 structure_value_addr))
2717 && (args_size.var
2718 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2719 structure_value_addr = copy_to_reg (structure_value_addr);
2721 /* Tail calls can make things harder to debug, and we've traditionally
2722 pushed these optimizations into -O2. Don't try if we're already
2723 expanding a call, as that means we're an argument. Don't try if
2724 there's cleanups, as we know there's code to follow the call. */
2726 if (currently_expanding_call++ != 0
2727 || !flag_optimize_sibling_calls
2728 || args_size.var
2729 || dbg_cnt (tail_call) == false)
2730 try_tail_call = 0;
2732 /* Rest of purposes for tail call optimizations to fail. */
2733 if (!try_tail_call
2734 || !targetm.have_sibcall_epilogue ()
2735 /* Doing sibling call optimization needs some work, since
2736 structure_value_addr can be allocated on the stack.
2737 It does not seem worth the effort since few optimizable
2738 sibling calls will return a structure. */
2739 || structure_value_addr != NULL_RTX
2740 #ifdef REG_PARM_STACK_SPACE
2741 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2742 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2743 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2744 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl))
2745 #endif
2746 /* Check whether the target is able to optimize the call
2747 into a sibcall. */
2748 || !targetm.function_ok_for_sibcall (fndecl, exp)
2749 /* Functions that do not return exactly once may not be sibcall
2750 optimized. */
2751 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2752 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2753 /* If the called function is nested in the current one, it might access
2754 some of the caller's arguments, but could clobber them beforehand if
2755 the argument areas are shared. */
2756 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2757 /* If this function requires more stack slots than the current
2758 function, we cannot change it into a sibling call.
2759 crtl->args.pretend_args_size is not part of the
2760 stack allocated by our caller. */
2761 || args_size.constant > (crtl->args.size
2762 - crtl->args.pretend_args_size)
2763 /* If the callee pops its own arguments, then it must pop exactly
2764 the same number of arguments as the current function. */
2765 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2766 != targetm.calls.return_pops_args (current_function_decl,
2767 TREE_TYPE (current_function_decl),
2768 crtl->args.size))
2769 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2770 try_tail_call = 0;
2772 /* Check if caller and callee disagree in promotion of function
2773 return value. */
2774 if (try_tail_call)
2776 machine_mode caller_mode, caller_promoted_mode;
2777 machine_mode callee_mode, callee_promoted_mode;
2778 int caller_unsignedp, callee_unsignedp;
2779 tree caller_res = DECL_RESULT (current_function_decl);
2781 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2782 caller_mode = DECL_MODE (caller_res);
2783 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2784 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2785 caller_promoted_mode
2786 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2787 &caller_unsignedp,
2788 TREE_TYPE (current_function_decl), 1);
2789 callee_promoted_mode
2790 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2791 &callee_unsignedp,
2792 funtype, 1);
2793 if (caller_mode != VOIDmode
2794 && (caller_promoted_mode != callee_promoted_mode
2795 || ((caller_mode != caller_promoted_mode
2796 || callee_mode != callee_promoted_mode)
2797 && (caller_unsignedp != callee_unsignedp
2798 || GET_MODE_BITSIZE (caller_mode)
2799 < GET_MODE_BITSIZE (callee_mode)))))
2800 try_tail_call = 0;
2803 /* Ensure current function's preferred stack boundary is at least
2804 what we need. Stack alignment may also increase preferred stack
2805 boundary. */
2806 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2807 crtl->preferred_stack_boundary = preferred_stack_boundary;
2808 else
2809 preferred_stack_boundary = crtl->preferred_stack_boundary;
2811 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2813 /* We want to make two insn chains; one for a sibling call, the other
2814 for a normal call. We will select one of the two chains after
2815 initial RTL generation is complete. */
2816 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2818 int sibcall_failure = 0;
2819 /* We want to emit any pending stack adjustments before the tail
2820 recursion "call". That way we know any adjustment after the tail
2821 recursion call can be ignored if we indeed use the tail
2822 call expansion. */
2823 saved_pending_stack_adjust save;
2824 rtx_insn *insns, *before_call, *after_args;
2825 rtx next_arg_reg;
2827 if (pass == 0)
2829 /* State variables we need to save and restore between
2830 iterations. */
2831 save_pending_stack_adjust (&save);
2833 if (pass)
2834 flags &= ~ECF_SIBCALL;
2835 else
2836 flags |= ECF_SIBCALL;
2838 /* Other state variables that we must reinitialize each time
2839 through the loop (that are not initialized by the loop itself). */
2840 argblock = 0;
2841 call_fusage = 0;
2843 /* Start a new sequence for the normal call case.
2845 From this point on, if the sibling call fails, we want to set
2846 sibcall_failure instead of continuing the loop. */
2847 start_sequence ();
2849 /* Don't let pending stack adjusts add up to too much.
2850 Also, do all pending adjustments now if there is any chance
2851 this might be a call to alloca or if we are expanding a sibling
2852 call sequence.
2853 Also do the adjustments before a throwing call, otherwise
2854 exception handling can fail; PR 19225. */
2855 if (pending_stack_adjust >= 32
2856 || (pending_stack_adjust > 0
2857 && (flags & ECF_MAY_BE_ALLOCA))
2858 || (pending_stack_adjust > 0
2859 && flag_exceptions && !(flags & ECF_NOTHROW))
2860 || pass == 0)
2861 do_pending_stack_adjust ();
2863 /* Precompute any arguments as needed. */
2864 if (pass)
2865 precompute_arguments (num_actuals, args);
2867 /* Now we are about to start emitting insns that can be deleted
2868 if a libcall is deleted. */
2869 if (pass && (flags & ECF_MALLOC))
2870 start_sequence ();
2872 if (pass == 0 && crtl->stack_protect_guard)
2873 stack_protect_epilogue ();
2875 adjusted_args_size = args_size;
2876 /* Compute the actual size of the argument block required. The variable
2877 and constant sizes must be combined, the size may have to be rounded,
2878 and there may be a minimum required size. When generating a sibcall
2879 pattern, do not round up, since we'll be re-using whatever space our
2880 caller provided. */
2881 unadjusted_args_size
2882 = compute_argument_block_size (reg_parm_stack_space,
2883 &adjusted_args_size,
2884 fndecl, fntype,
2885 (pass == 0 ? 0
2886 : preferred_stack_boundary));
2888 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2890 /* The argument block when performing a sibling call is the
2891 incoming argument block. */
2892 if (pass == 0)
2894 argblock = crtl->args.internal_arg_pointer;
2895 if (STACK_GROWS_DOWNWARD)
2896 argblock
2897 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
2898 else
2899 argblock
2900 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
2902 stored_args_map = sbitmap_alloc (args_size.constant);
2903 bitmap_clear (stored_args_map);
2906 /* If we have no actual push instructions, or shouldn't use them,
2907 make space for all args right now. */
2908 else if (adjusted_args_size.var != 0)
2910 if (old_stack_level == 0)
2912 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2913 old_stack_pointer_delta = stack_pointer_delta;
2914 old_pending_adj = pending_stack_adjust;
2915 pending_stack_adjust = 0;
2916 /* stack_arg_under_construction says whether a stack arg is
2917 being constructed at the old stack level. Pushing the stack
2918 gets a clean outgoing argument block. */
2919 old_stack_arg_under_construction = stack_arg_under_construction;
2920 stack_arg_under_construction = 0;
2922 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2923 if (flag_stack_usage_info)
2924 current_function_has_unbounded_dynamic_stack_size = 1;
2926 else
2928 /* Note that we must go through the motions of allocating an argument
2929 block even if the size is zero because we may be storing args
2930 in the area reserved for register arguments, which may be part of
2931 the stack frame. */
2933 int needed = adjusted_args_size.constant;
2935 /* Store the maximum argument space used. It will be pushed by
2936 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2937 checking). */
2939 if (needed > crtl->outgoing_args_size)
2940 crtl->outgoing_args_size = needed;
2942 if (must_preallocate)
2944 if (ACCUMULATE_OUTGOING_ARGS)
2946 /* Since the stack pointer will never be pushed, it is
2947 possible for the evaluation of a parm to clobber
2948 something we have already written to the stack.
2949 Since most function calls on RISC machines do not use
2950 the stack, this is uncommon, but must work correctly.
2952 Therefore, we save any area of the stack that was already
2953 written and that we are using. Here we set up to do this
2954 by making a new stack usage map from the old one. The
2955 actual save will be done by store_one_arg.
2957 Another approach might be to try to reorder the argument
2958 evaluations to avoid this conflicting stack usage. */
2960 /* Since we will be writing into the entire argument area,
2961 the map must be allocated for its entire size, not just
2962 the part that is the responsibility of the caller. */
2963 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2964 needed += reg_parm_stack_space;
2966 if (ARGS_GROW_DOWNWARD)
2967 highest_outgoing_arg_in_use
2968 = MAX (initial_highest_arg_in_use, needed + 1);
2969 else
2970 highest_outgoing_arg_in_use
2971 = MAX (initial_highest_arg_in_use, needed);
2973 free (stack_usage_map_buf);
2974 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2975 stack_usage_map = stack_usage_map_buf;
2977 if (initial_highest_arg_in_use)
2978 memcpy (stack_usage_map, initial_stack_usage_map,
2979 initial_highest_arg_in_use);
2981 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2982 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2983 (highest_outgoing_arg_in_use
2984 - initial_highest_arg_in_use));
2985 needed = 0;
2987 /* The address of the outgoing argument list must not be
2988 copied to a register here, because argblock would be left
2989 pointing to the wrong place after the call to
2990 allocate_dynamic_stack_space below. */
2992 argblock = virtual_outgoing_args_rtx;
2994 else
2996 if (inhibit_defer_pop == 0)
2998 /* Try to reuse some or all of the pending_stack_adjust
2999 to get this space. */
3000 needed
3001 = (combine_pending_stack_adjustment_and_call
3002 (unadjusted_args_size,
3003 &adjusted_args_size,
3004 preferred_unit_stack_boundary));
3006 /* combine_pending_stack_adjustment_and_call computes
3007 an adjustment before the arguments are allocated.
3008 Account for them and see whether or not the stack
3009 needs to go up or down. */
3010 needed = unadjusted_args_size - needed;
3012 if (needed < 0)
3014 /* We're releasing stack space. */
3015 /* ??? We can avoid any adjustment at all if we're
3016 already aligned. FIXME. */
3017 pending_stack_adjust = -needed;
3018 do_pending_stack_adjust ();
3019 needed = 0;
3021 else
3022 /* We need to allocate space. We'll do that in
3023 push_block below. */
3024 pending_stack_adjust = 0;
3027 /* Special case this because overhead of `push_block' in
3028 this case is non-trivial. */
3029 if (needed == 0)
3030 argblock = virtual_outgoing_args_rtx;
3031 else
3033 argblock = push_block (GEN_INT (needed), 0, 0);
3034 if (ARGS_GROW_DOWNWARD)
3035 argblock = plus_constant (Pmode, argblock, needed);
3038 /* We only really need to call `copy_to_reg' in the case
3039 where push insns are going to be used to pass ARGBLOCK
3040 to a function call in ARGS. In that case, the stack
3041 pointer changes value from the allocation point to the
3042 call point, and hence the value of
3043 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3044 as well always do it. */
3045 argblock = copy_to_reg (argblock);
3050 if (ACCUMULATE_OUTGOING_ARGS)
3052 /* The save/restore code in store_one_arg handles all
3053 cases except one: a constructor call (including a C
3054 function returning a BLKmode struct) to initialize
3055 an argument. */
3056 if (stack_arg_under_construction)
3058 rtx push_size
3059 = GEN_INT (adjusted_args_size.constant
3060 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3061 : TREE_TYPE (fndecl))) ? 0
3062 : reg_parm_stack_space));
3063 if (old_stack_level == 0)
3065 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3066 old_stack_pointer_delta = stack_pointer_delta;
3067 old_pending_adj = pending_stack_adjust;
3068 pending_stack_adjust = 0;
3069 /* stack_arg_under_construction says whether a stack
3070 arg is being constructed at the old stack level.
3071 Pushing the stack gets a clean outgoing argument
3072 block. */
3073 old_stack_arg_under_construction
3074 = stack_arg_under_construction;
3075 stack_arg_under_construction = 0;
3076 /* Make a new map for the new argument list. */
3077 free (stack_usage_map_buf);
3078 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3079 stack_usage_map = stack_usage_map_buf;
3080 highest_outgoing_arg_in_use = 0;
3082 /* We can pass TRUE as the 4th argument because we just
3083 saved the stack pointer and will restore it right after
3084 the call. */
3085 allocate_dynamic_stack_space (push_size, 0,
3086 BIGGEST_ALIGNMENT, true);
3089 /* If argument evaluation might modify the stack pointer,
3090 copy the address of the argument list to a register. */
3091 for (i = 0; i < num_actuals; i++)
3092 if (args[i].pass_on_stack)
3094 argblock = copy_addr_to_reg (argblock);
3095 break;
3099 compute_argument_addresses (args, argblock, num_actuals);
3101 /* Stack is properly aligned, pops can't safely be deferred during
3102 the evaluation of the arguments. */
3103 NO_DEFER_POP;
3105 /* Precompute all register parameters. It isn't safe to compute
3106 anything once we have started filling any specific hard regs.
3107 TLS symbols sometimes need a call to resolve. Precompute
3108 register parameters before any stack pointer manipulation
3109 to avoid unaligned stack in the called function. */
3110 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3112 OK_DEFER_POP;
3114 /* Perform stack alignment before the first push (the last arg). */
3115 if (argblock == 0
3116 && adjusted_args_size.constant > reg_parm_stack_space
3117 && adjusted_args_size.constant != unadjusted_args_size)
3119 /* When the stack adjustment is pending, we get better code
3120 by combining the adjustments. */
3121 if (pending_stack_adjust
3122 && ! inhibit_defer_pop)
3124 pending_stack_adjust
3125 = (combine_pending_stack_adjustment_and_call
3126 (unadjusted_args_size,
3127 &adjusted_args_size,
3128 preferred_unit_stack_boundary));
3129 do_pending_stack_adjust ();
3131 else if (argblock == 0)
3132 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3133 - unadjusted_args_size));
3135 /* Now that the stack is properly aligned, pops can't safely
3136 be deferred during the evaluation of the arguments. */
3137 NO_DEFER_POP;
3139 /* Record the maximum pushed stack space size. We need to delay
3140 doing it this far to take into account the optimization done
3141 by combine_pending_stack_adjustment_and_call. */
3142 if (flag_stack_usage_info
3143 && !ACCUMULATE_OUTGOING_ARGS
3144 && pass
3145 && adjusted_args_size.var == 0)
3147 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3148 if (pushed > current_function_pushed_stack_size)
3149 current_function_pushed_stack_size = pushed;
3152 funexp = rtx_for_function_call (fndecl, addr);
3154 if (CALL_EXPR_STATIC_CHAIN (exp))
3155 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3156 else
3157 static_chain_value = 0;
3159 #ifdef REG_PARM_STACK_SPACE
3160 /* Save the fixed argument area if it's part of the caller's frame and
3161 is clobbered by argument setup for this call. */
3162 if (ACCUMULATE_OUTGOING_ARGS && pass)
3163 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3164 &low_to_save, &high_to_save);
3165 #endif
3167 /* Now store (and compute if necessary) all non-register parms.
3168 These come before register parms, since they can require block-moves,
3169 which could clobber the registers used for register parms.
3170 Parms which have partial registers are not stored here,
3171 but we do preallocate space here if they want that. */
3173 for (i = 0; i < num_actuals; i++)
3175 /* Delay bounds until all other args are stored. */
3176 if (POINTER_BOUNDS_P (args[i].tree_value))
3177 continue;
3178 else if (args[i].reg == 0 || args[i].pass_on_stack)
3180 rtx_insn *before_arg = get_last_insn ();
3182 /* We don't allow passing huge (> 2^30 B) arguments
3183 by value. It would cause an overflow later on. */
3184 if (adjusted_args_size.constant
3185 >= (1 << (HOST_BITS_PER_INT - 2)))
3187 sorry ("passing too large argument on stack");
3188 continue;
3191 if (store_one_arg (&args[i], argblock, flags,
3192 adjusted_args_size.var != 0,
3193 reg_parm_stack_space)
3194 || (pass == 0
3195 && check_sibcall_argument_overlap (before_arg,
3196 &args[i], 1)))
3197 sibcall_failure = 1;
3200 if (args[i].stack)
3201 call_fusage
3202 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3203 gen_rtx_USE (VOIDmode, args[i].stack),
3204 call_fusage);
3207 /* If we have a parm that is passed in registers but not in memory
3208 and whose alignment does not permit a direct copy into registers,
3209 make a group of pseudos that correspond to each register that we
3210 will later fill. */
3211 if (STRICT_ALIGNMENT)
3212 store_unaligned_arguments_into_pseudos (args, num_actuals);
3214 /* Now store any partially-in-registers parm.
3215 This is the last place a block-move can happen. */
3216 if (reg_parm_seen)
3217 for (i = 0; i < num_actuals; i++)
3218 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3220 rtx_insn *before_arg = get_last_insn ();
3222 /* On targets with weird calling conventions (e.g. PA) it's
3223 hard to ensure that all cases of argument overlap between
3224 stack and registers work. Play it safe and bail out. */
3225 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3227 sibcall_failure = 1;
3228 break;
3231 if (store_one_arg (&args[i], argblock, flags,
3232 adjusted_args_size.var != 0,
3233 reg_parm_stack_space)
3234 || (pass == 0
3235 && check_sibcall_argument_overlap (before_arg,
3236 &args[i], 1)))
3237 sibcall_failure = 1;
3240 bool any_regs = false;
3241 for (i = 0; i < num_actuals; i++)
3242 if (args[i].reg != NULL_RTX)
3244 any_regs = true;
3245 targetm.calls.call_args (args[i].reg, funtype);
3247 if (!any_regs)
3248 targetm.calls.call_args (pc_rtx, funtype);
3250 /* Figure out the register where the value, if any, will come back. */
3251 valreg = 0;
3252 valbnd = 0;
3253 if (TYPE_MODE (rettype) != VOIDmode
3254 && ! structure_value_addr)
3256 if (pcc_struct_value)
3258 valreg = hard_function_value (build_pointer_type (rettype),
3259 fndecl, NULL, (pass == 0));
3260 if (CALL_WITH_BOUNDS_P (exp))
3261 valbnd = targetm.calls.
3262 chkp_function_value_bounds (build_pointer_type (rettype),
3263 fndecl, (pass == 0));
3265 else
3267 valreg = hard_function_value (rettype, fndecl, fntype,
3268 (pass == 0));
3269 if (CALL_WITH_BOUNDS_P (exp))
3270 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3271 fndecl,
3272 (pass == 0));
3275 /* If VALREG is a PARALLEL whose first member has a zero
3276 offset, use that. This is for targets such as m68k that
3277 return the same value in multiple places. */
3278 if (GET_CODE (valreg) == PARALLEL)
3280 rtx elem = XVECEXP (valreg, 0, 0);
3281 rtx where = XEXP (elem, 0);
3282 rtx offset = XEXP (elem, 1);
3283 if (offset == const0_rtx
3284 && GET_MODE (where) == GET_MODE (valreg))
3285 valreg = where;
3289 /* Store all bounds not passed in registers. */
3290 for (i = 0; i < num_actuals; i++)
3292 if (POINTER_BOUNDS_P (args[i].tree_value)
3293 && !args[i].reg)
3294 store_bounds (&args[i],
3295 args[i].pointer_arg == -1
3296 ? NULL
3297 : &args[args[i].pointer_arg]);
3300 /* If register arguments require space on the stack and stack space
3301 was not preallocated, allocate stack space here for arguments
3302 passed in registers. */
3303 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3304 && !ACCUMULATE_OUTGOING_ARGS
3305 && must_preallocate == 0 && reg_parm_stack_space > 0)
3306 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3308 /* Pass the function the address in which to return a
3309 structure value. */
3310 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3312 structure_value_addr
3313 = convert_memory_address (Pmode, structure_value_addr);
3314 emit_move_insn (struct_value,
3315 force_reg (Pmode,
3316 force_operand (structure_value_addr,
3317 NULL_RTX)));
3319 if (REG_P (struct_value))
3320 use_reg (&call_fusage, struct_value);
3323 after_args = get_last_insn ();
3324 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3325 static_chain_value, &call_fusage,
3326 reg_parm_seen, pass == 0);
3328 load_register_parameters (args, num_actuals, &call_fusage, flags,
3329 pass == 0, &sibcall_failure);
3331 /* Save a pointer to the last insn before the call, so that we can
3332 later safely search backwards to find the CALL_INSN. */
3333 before_call = get_last_insn ();
3335 /* Set up next argument register. For sibling calls on machines
3336 with register windows this should be the incoming register. */
3337 if (pass == 0)
3338 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3339 VOIDmode,
3340 void_type_node,
3341 true);
3342 else
3343 next_arg_reg = targetm.calls.function_arg (args_so_far,
3344 VOIDmode, void_type_node,
3345 true);
3347 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3349 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3350 arg_nr = num_actuals - arg_nr - 1;
3351 if (arg_nr >= 0
3352 && arg_nr < num_actuals
3353 && args[arg_nr].reg
3354 && valreg
3355 && REG_P (valreg)
3356 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3357 call_fusage
3358 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3359 gen_rtx_SET (valreg, args[arg_nr].reg),
3360 call_fusage);
3362 /* All arguments and registers used for the call must be set up by
3363 now! */
3365 /* Stack must be properly aligned now. */
3366 gcc_assert (!pass
3367 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3369 /* Generate the actual call instruction. */
3370 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3371 adjusted_args_size.constant, struct_value_size,
3372 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3373 flags, args_so_far);
3375 if (flag_ipa_ra)
3377 rtx_call_insn *last;
3378 rtx datum = NULL_RTX;
3379 if (fndecl != NULL_TREE)
3381 datum = XEXP (DECL_RTL (fndecl), 0);
3382 gcc_assert (datum != NULL_RTX
3383 && GET_CODE (datum) == SYMBOL_REF);
3385 last = last_call_insn ();
3386 add_reg_note (last, REG_CALL_DECL, datum);
3389 /* If the call setup or the call itself overlaps with anything
3390 of the argument setup we probably clobbered our call address.
3391 In that case we can't do sibcalls. */
3392 if (pass == 0
3393 && check_sibcall_argument_overlap (after_args, 0, 0))
3394 sibcall_failure = 1;
3396 /* If a non-BLKmode value is returned at the most significant end
3397 of a register, shift the register right by the appropriate amount
3398 and update VALREG accordingly. BLKmode values are handled by the
3399 group load/store machinery below. */
3400 if (!structure_value_addr
3401 && !pcc_struct_value
3402 && TYPE_MODE (rettype) != VOIDmode
3403 && TYPE_MODE (rettype) != BLKmode
3404 && REG_P (valreg)
3405 && targetm.calls.return_in_msb (rettype))
3407 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3408 sibcall_failure = 1;
3409 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3412 if (pass && (flags & ECF_MALLOC))
3414 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3415 rtx_insn *last, *insns;
3417 /* The return value from a malloc-like function is a pointer. */
3418 if (TREE_CODE (rettype) == POINTER_TYPE)
3419 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3421 emit_move_insn (temp, valreg);
3423 /* The return value from a malloc-like function can not alias
3424 anything else. */
3425 last = get_last_insn ();
3426 add_reg_note (last, REG_NOALIAS, temp);
3428 /* Write out the sequence. */
3429 insns = get_insns ();
3430 end_sequence ();
3431 emit_insn (insns);
3432 valreg = temp;
3435 /* For calls to `setjmp', etc., inform
3436 function.c:setjmp_warnings that it should complain if
3437 nonvolatile values are live. For functions that cannot
3438 return, inform flow that control does not fall through. */
3440 if ((flags & ECF_NORETURN) || pass == 0)
3442 /* The barrier must be emitted
3443 immediately after the CALL_INSN. Some ports emit more
3444 than just a CALL_INSN above, so we must search for it here. */
3446 rtx_insn *last = get_last_insn ();
3447 while (!CALL_P (last))
3449 last = PREV_INSN (last);
3450 /* There was no CALL_INSN? */
3451 gcc_assert (last != before_call);
3454 emit_barrier_after (last);
3456 /* Stack adjustments after a noreturn call are dead code.
3457 However when NO_DEFER_POP is in effect, we must preserve
3458 stack_pointer_delta. */
3459 if (inhibit_defer_pop == 0)
3461 stack_pointer_delta = old_stack_allocated;
3462 pending_stack_adjust = 0;
3466 /* If value type not void, return an rtx for the value. */
3468 if (TYPE_MODE (rettype) == VOIDmode
3469 || ignore)
3470 target = const0_rtx;
3471 else if (structure_value_addr)
3473 if (target == 0 || !MEM_P (target))
3475 target
3476 = gen_rtx_MEM (TYPE_MODE (rettype),
3477 memory_address (TYPE_MODE (rettype),
3478 structure_value_addr));
3479 set_mem_attributes (target, rettype, 1);
3482 else if (pcc_struct_value)
3484 /* This is the special C++ case where we need to
3485 know what the true target was. We take care to
3486 never use this value more than once in one expression. */
3487 target = gen_rtx_MEM (TYPE_MODE (rettype),
3488 copy_to_reg (valreg));
3489 set_mem_attributes (target, rettype, 1);
3491 /* Handle calls that return values in multiple non-contiguous locations.
3492 The Irix 6 ABI has examples of this. */
3493 else if (GET_CODE (valreg) == PARALLEL)
3495 if (target == 0)
3496 target = emit_group_move_into_temps (valreg);
3497 else if (rtx_equal_p (target, valreg))
3499 else if (GET_CODE (target) == PARALLEL)
3500 /* Handle the result of a emit_group_move_into_temps
3501 call in the previous pass. */
3502 emit_group_move (target, valreg);
3503 else
3504 emit_group_store (target, valreg, rettype,
3505 int_size_in_bytes (rettype));
3507 else if (target
3508 && GET_MODE (target) == TYPE_MODE (rettype)
3509 && GET_MODE (target) == GET_MODE (valreg))
3511 bool may_overlap = false;
3513 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3514 reg to a plain register. */
3515 if (!REG_P (target) || HARD_REGISTER_P (target))
3516 valreg = avoid_likely_spilled_reg (valreg);
3518 /* If TARGET is a MEM in the argument area, and we have
3519 saved part of the argument area, then we can't store
3520 directly into TARGET as it may get overwritten when we
3521 restore the argument save area below. Don't work too
3522 hard though and simply force TARGET to a register if it
3523 is a MEM; the optimizer is quite likely to sort it out. */
3524 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3525 for (i = 0; i < num_actuals; i++)
3526 if (args[i].save_area)
3528 may_overlap = true;
3529 break;
3532 if (may_overlap)
3533 target = copy_to_reg (valreg);
3534 else
3536 /* TARGET and VALREG cannot be equal at this point
3537 because the latter would not have
3538 REG_FUNCTION_VALUE_P true, while the former would if
3539 it were referring to the same register.
3541 If they refer to the same register, this move will be
3542 a no-op, except when function inlining is being
3543 done. */
3544 emit_move_insn (target, valreg);
3546 /* If we are setting a MEM, this code must be executed.
3547 Since it is emitted after the call insn, sibcall
3548 optimization cannot be performed in that case. */
3549 if (MEM_P (target))
3550 sibcall_failure = 1;
3553 else
3554 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3556 /* If we promoted this return value, make the proper SUBREG.
3557 TARGET might be const0_rtx here, so be careful. */
3558 if (REG_P (target)
3559 && TYPE_MODE (rettype) != BLKmode
3560 && GET_MODE (target) != TYPE_MODE (rettype))
3562 tree type = rettype;
3563 int unsignedp = TYPE_UNSIGNED (type);
3564 int offset = 0;
3565 machine_mode pmode;
3567 /* Ensure we promote as expected, and get the new unsignedness. */
3568 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3569 funtype, 1);
3570 gcc_assert (GET_MODE (target) == pmode);
3572 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3573 && (GET_MODE_SIZE (GET_MODE (target))
3574 > GET_MODE_SIZE (TYPE_MODE (type))))
3576 offset = GET_MODE_SIZE (GET_MODE (target))
3577 - GET_MODE_SIZE (TYPE_MODE (type));
3578 if (! BYTES_BIG_ENDIAN)
3579 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3580 else if (! WORDS_BIG_ENDIAN)
3581 offset %= UNITS_PER_WORD;
3584 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3585 SUBREG_PROMOTED_VAR_P (target) = 1;
3586 SUBREG_PROMOTED_SET (target, unsignedp);
3589 /* If size of args is variable or this was a constructor call for a stack
3590 argument, restore saved stack-pointer value. */
3592 if (old_stack_level)
3594 rtx_insn *prev = get_last_insn ();
3596 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3597 stack_pointer_delta = old_stack_pointer_delta;
3599 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3601 pending_stack_adjust = old_pending_adj;
3602 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3603 stack_arg_under_construction = old_stack_arg_under_construction;
3604 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3605 stack_usage_map = initial_stack_usage_map;
3606 sibcall_failure = 1;
3608 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3610 #ifdef REG_PARM_STACK_SPACE
3611 if (save_area)
3612 restore_fixed_argument_area (save_area, argblock,
3613 high_to_save, low_to_save);
3614 #endif
3616 /* If we saved any argument areas, restore them. */
3617 for (i = 0; i < num_actuals; i++)
3618 if (args[i].save_area)
3620 machine_mode save_mode = GET_MODE (args[i].save_area);
3621 rtx stack_area
3622 = gen_rtx_MEM (save_mode,
3623 memory_address (save_mode,
3624 XEXP (args[i].stack_slot, 0)));
3626 if (save_mode != BLKmode)
3627 emit_move_insn (stack_area, args[i].save_area);
3628 else
3629 emit_block_move (stack_area, args[i].save_area,
3630 GEN_INT (args[i].locate.size.constant),
3631 BLOCK_OP_CALL_PARM);
3634 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3635 stack_usage_map = initial_stack_usage_map;
3638 /* If this was alloca, record the new stack level. */
3639 if (flags & ECF_MAY_BE_ALLOCA)
3640 record_new_stack_level ();
3642 /* Free up storage we no longer need. */
3643 for (i = 0; i < num_actuals; ++i)
3644 free (args[i].aligned_regs);
3646 targetm.calls.end_call_args ();
3648 insns = get_insns ();
3649 end_sequence ();
3651 if (pass == 0)
3653 tail_call_insns = insns;
3655 /* Restore the pending stack adjustment now that we have
3656 finished generating the sibling call sequence. */
3658 restore_pending_stack_adjust (&save);
3660 /* Prepare arg structure for next iteration. */
3661 for (i = 0; i < num_actuals; i++)
3663 args[i].value = 0;
3664 args[i].aligned_regs = 0;
3665 args[i].stack = 0;
3668 sbitmap_free (stored_args_map);
3669 internal_arg_pointer_exp_state.scan_start = NULL;
3670 internal_arg_pointer_exp_state.cache.release ();
3672 else
3674 normal_call_insns = insns;
3676 /* Verify that we've deallocated all the stack we used. */
3677 gcc_assert ((flags & ECF_NORETURN)
3678 || (old_stack_allocated
3679 == stack_pointer_delta - pending_stack_adjust));
3682 /* If something prevents making this a sibling call,
3683 zero out the sequence. */
3684 if (sibcall_failure)
3685 tail_call_insns = NULL;
3686 else
3687 break;
3690 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3691 arguments too, as argument area is now clobbered by the call. */
3692 if (tail_call_insns)
3694 emit_insn (tail_call_insns);
3695 crtl->tail_call_emit = true;
3697 else
3698 emit_insn (normal_call_insns);
3700 currently_expanding_call--;
3702 free (stack_usage_map_buf);
3704 /* Join result with returned bounds so caller may use them if needed. */
3705 target = chkp_join_splitted_slot (target, valbnd);
3707 return target;
3710 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3711 this function's incoming arguments.
3713 At the start of RTL generation we know the only REG_EQUIV notes
3714 in the rtl chain are those for incoming arguments, so we can look
3715 for REG_EQUIV notes between the start of the function and the
3716 NOTE_INSN_FUNCTION_BEG.
3718 This is (slight) overkill. We could keep track of the highest
3719 argument we clobber and be more selective in removing notes, but it
3720 does not seem to be worth the effort. */
3722 void
3723 fixup_tail_calls (void)
3725 rtx_insn *insn;
3727 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3729 rtx note;
3731 /* There are never REG_EQUIV notes for the incoming arguments
3732 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3733 if (NOTE_P (insn)
3734 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3735 break;
3737 note = find_reg_note (insn, REG_EQUIV, 0);
3738 if (note)
3739 remove_note (insn, note);
3740 note = find_reg_note (insn, REG_EQUIV, 0);
3741 gcc_assert (!note);
3745 /* Traverse a list of TYPES and expand all complex types into their
3746 components. */
3747 static tree
3748 split_complex_types (tree types)
3750 tree p;
3752 /* Before allocating memory, check for the common case of no complex. */
3753 for (p = types; p; p = TREE_CHAIN (p))
3755 tree type = TREE_VALUE (p);
3756 if (TREE_CODE (type) == COMPLEX_TYPE
3757 && targetm.calls.split_complex_arg (type))
3758 goto found;
3760 return types;
3762 found:
3763 types = copy_list (types);
3765 for (p = types; p; p = TREE_CHAIN (p))
3767 tree complex_type = TREE_VALUE (p);
3769 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3770 && targetm.calls.split_complex_arg (complex_type))
3772 tree next, imag;
3774 /* Rewrite complex type with component type. */
3775 TREE_VALUE (p) = TREE_TYPE (complex_type);
3776 next = TREE_CHAIN (p);
3778 /* Add another component type for the imaginary part. */
3779 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3780 TREE_CHAIN (p) = imag;
3781 TREE_CHAIN (imag) = next;
3783 /* Skip the newly created node. */
3784 p = TREE_CHAIN (p);
3788 return types;
3791 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3792 The RETVAL parameter specifies whether return value needs to be saved, other
3793 parameters are documented in the emit_library_call function below. */
3795 static rtx
3796 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3797 enum libcall_type fn_type,
3798 machine_mode outmode, int nargs, va_list p)
3800 /* Total size in bytes of all the stack-parms scanned so far. */
3801 struct args_size args_size;
3802 /* Size of arguments before any adjustments (such as rounding). */
3803 struct args_size original_args_size;
3804 int argnum;
3805 rtx fun;
3806 /* Todo, choose the correct decl type of orgfun. Sadly this information
3807 isn't present here, so we default to native calling abi here. */
3808 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3809 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3810 int count;
3811 rtx argblock = 0;
3812 CUMULATIVE_ARGS args_so_far_v;
3813 cumulative_args_t args_so_far;
3814 struct arg
3816 rtx value;
3817 machine_mode mode;
3818 rtx reg;
3819 int partial;
3820 struct locate_and_pad_arg_data locate;
3821 rtx save_area;
3823 struct arg *argvec;
3824 int old_inhibit_defer_pop = inhibit_defer_pop;
3825 rtx call_fusage = 0;
3826 rtx mem_value = 0;
3827 rtx valreg;
3828 int pcc_struct_value = 0;
3829 int struct_value_size = 0;
3830 int flags;
3831 int reg_parm_stack_space = 0;
3832 int needed;
3833 rtx_insn *before_call;
3834 bool have_push_fusage;
3835 tree tfom; /* type_for_mode (outmode, 0) */
3837 #ifdef REG_PARM_STACK_SPACE
3838 /* Define the boundary of the register parm stack space that needs to be
3839 save, if any. */
3840 int low_to_save = 0, high_to_save = 0;
3841 rtx save_area = 0; /* Place that it is saved. */
3842 #endif
3844 /* Size of the stack reserved for parameter registers. */
3845 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3846 char *initial_stack_usage_map = stack_usage_map;
3847 char *stack_usage_map_buf = NULL;
3849 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3851 #ifdef REG_PARM_STACK_SPACE
3852 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3853 #endif
3855 /* By default, library functions can not throw. */
3856 flags = ECF_NOTHROW;
3858 switch (fn_type)
3860 case LCT_NORMAL:
3861 break;
3862 case LCT_CONST:
3863 flags |= ECF_CONST;
3864 break;
3865 case LCT_PURE:
3866 flags |= ECF_PURE;
3867 break;
3868 case LCT_NORETURN:
3869 flags |= ECF_NORETURN;
3870 break;
3871 case LCT_THROW:
3872 flags = ECF_NORETURN;
3873 break;
3874 case LCT_RETURNS_TWICE:
3875 flags = ECF_RETURNS_TWICE;
3876 break;
3878 fun = orgfun;
3880 /* Ensure current function's preferred stack boundary is at least
3881 what we need. */
3882 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3883 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3885 /* If this kind of value comes back in memory,
3886 decide where in memory it should come back. */
3887 if (outmode != VOIDmode)
3889 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3890 if (aggregate_value_p (tfom, 0))
3892 #ifdef PCC_STATIC_STRUCT_RETURN
3893 rtx pointer_reg
3894 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3895 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3896 pcc_struct_value = 1;
3897 if (value == 0)
3898 value = gen_reg_rtx (outmode);
3899 #else /* not PCC_STATIC_STRUCT_RETURN */
3900 struct_value_size = GET_MODE_SIZE (outmode);
3901 if (value != 0 && MEM_P (value))
3902 mem_value = value;
3903 else
3904 mem_value = assign_temp (tfom, 1, 1);
3905 #endif
3906 /* This call returns a big structure. */
3907 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3910 else
3911 tfom = void_type_node;
3913 /* ??? Unfinished: must pass the memory address as an argument. */
3915 /* Copy all the libcall-arguments out of the varargs data
3916 and into a vector ARGVEC.
3918 Compute how to pass each argument. We only support a very small subset
3919 of the full argument passing conventions to limit complexity here since
3920 library functions shouldn't have many args. */
3922 argvec = XALLOCAVEC (struct arg, nargs + 1);
3923 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3925 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3926 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3927 #else
3928 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3929 #endif
3930 args_so_far = pack_cumulative_args (&args_so_far_v);
3932 args_size.constant = 0;
3933 args_size.var = 0;
3935 count = 0;
3937 push_temp_slots ();
3939 /* If there's a structure value address to be passed,
3940 either pass it in the special place, or pass it as an extra argument. */
3941 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3943 rtx addr = XEXP (mem_value, 0);
3945 nargs++;
3947 /* Make sure it is a reasonable operand for a move or push insn. */
3948 if (!REG_P (addr) && !MEM_P (addr)
3949 && !(CONSTANT_P (addr)
3950 && targetm.legitimate_constant_p (Pmode, addr)))
3951 addr = force_operand (addr, NULL_RTX);
3953 argvec[count].value = addr;
3954 argvec[count].mode = Pmode;
3955 argvec[count].partial = 0;
3957 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3958 Pmode, NULL_TREE, true);
3959 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3960 NULL_TREE, 1) == 0);
3962 locate_and_pad_parm (Pmode, NULL_TREE,
3963 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3965 #else
3966 argvec[count].reg != 0,
3967 #endif
3968 reg_parm_stack_space, 0,
3969 NULL_TREE, &args_size, &argvec[count].locate);
3971 if (argvec[count].reg == 0 || argvec[count].partial != 0
3972 || reg_parm_stack_space > 0)
3973 args_size.constant += argvec[count].locate.size.constant;
3975 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3977 count++;
3980 for (; count < nargs; count++)
3982 rtx val = va_arg (p, rtx);
3983 machine_mode mode = (machine_mode) va_arg (p, int);
3984 int unsigned_p = 0;
3986 /* We cannot convert the arg value to the mode the library wants here;
3987 must do it earlier where we know the signedness of the arg. */
3988 gcc_assert (mode != BLKmode
3989 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3991 /* Make sure it is a reasonable operand for a move or push insn. */
3992 if (!REG_P (val) && !MEM_P (val)
3993 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3994 val = force_operand (val, NULL_RTX);
3996 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3998 rtx slot;
3999 int must_copy
4000 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4002 /* If this was a CONST function, it is now PURE since it now
4003 reads memory. */
4004 if (flags & ECF_CONST)
4006 flags &= ~ECF_CONST;
4007 flags |= ECF_PURE;
4010 if (MEM_P (val) && !must_copy)
4012 tree val_expr = MEM_EXPR (val);
4013 if (val_expr)
4014 mark_addressable (val_expr);
4015 slot = val;
4017 else
4019 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4020 1, 1);
4021 emit_move_insn (slot, val);
4024 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4025 gen_rtx_USE (VOIDmode, slot),
4026 call_fusage);
4027 if (must_copy)
4028 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4029 gen_rtx_CLOBBER (VOIDmode,
4030 slot),
4031 call_fusage);
4033 mode = Pmode;
4034 val = force_operand (XEXP (slot, 0), NULL_RTX);
4037 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4038 argvec[count].mode = mode;
4039 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4040 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4041 NULL_TREE, true);
4043 argvec[count].partial
4044 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4046 if (argvec[count].reg == 0
4047 || argvec[count].partial != 0
4048 || reg_parm_stack_space > 0)
4050 locate_and_pad_parm (mode, NULL_TREE,
4051 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4053 #else
4054 argvec[count].reg != 0,
4055 #endif
4056 reg_parm_stack_space, argvec[count].partial,
4057 NULL_TREE, &args_size, &argvec[count].locate);
4058 args_size.constant += argvec[count].locate.size.constant;
4059 gcc_assert (!argvec[count].locate.size.var);
4061 #ifdef BLOCK_REG_PADDING
4062 else
4063 /* The argument is passed entirely in registers. See at which
4064 end it should be padded. */
4065 argvec[count].locate.where_pad =
4066 BLOCK_REG_PADDING (mode, NULL_TREE,
4067 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4068 #endif
4070 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4073 /* If this machine requires an external definition for library
4074 functions, write one out. */
4075 assemble_external_libcall (fun);
4077 original_args_size = args_size;
4078 args_size.constant = (((args_size.constant
4079 + stack_pointer_delta
4080 + STACK_BYTES - 1)
4081 / STACK_BYTES
4082 * STACK_BYTES)
4083 - stack_pointer_delta);
4085 args_size.constant = MAX (args_size.constant,
4086 reg_parm_stack_space);
4088 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4089 args_size.constant -= reg_parm_stack_space;
4091 if (args_size.constant > crtl->outgoing_args_size)
4092 crtl->outgoing_args_size = args_size.constant;
4094 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4096 int pushed = args_size.constant + pending_stack_adjust;
4097 if (pushed > current_function_pushed_stack_size)
4098 current_function_pushed_stack_size = pushed;
4101 if (ACCUMULATE_OUTGOING_ARGS)
4103 /* Since the stack pointer will never be pushed, it is possible for
4104 the evaluation of a parm to clobber something we have already
4105 written to the stack. Since most function calls on RISC machines
4106 do not use the stack, this is uncommon, but must work correctly.
4108 Therefore, we save any area of the stack that was already written
4109 and that we are using. Here we set up to do this by making a new
4110 stack usage map from the old one.
4112 Another approach might be to try to reorder the argument
4113 evaluations to avoid this conflicting stack usage. */
4115 needed = args_size.constant;
4117 /* Since we will be writing into the entire argument area, the
4118 map must be allocated for its entire size, not just the part that
4119 is the responsibility of the caller. */
4120 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4121 needed += reg_parm_stack_space;
4123 if (ARGS_GROW_DOWNWARD)
4124 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4125 needed + 1);
4126 else
4127 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4129 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4130 stack_usage_map = stack_usage_map_buf;
4132 if (initial_highest_arg_in_use)
4133 memcpy (stack_usage_map, initial_stack_usage_map,
4134 initial_highest_arg_in_use);
4136 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4137 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4138 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4139 needed = 0;
4141 /* We must be careful to use virtual regs before they're instantiated,
4142 and real regs afterwards. Loop optimization, for example, can create
4143 new libcalls after we've instantiated the virtual regs, and if we
4144 use virtuals anyway, they won't match the rtl patterns. */
4146 if (virtuals_instantiated)
4147 argblock = plus_constant (Pmode, stack_pointer_rtx,
4148 STACK_POINTER_OFFSET);
4149 else
4150 argblock = virtual_outgoing_args_rtx;
4152 else
4154 if (!PUSH_ARGS)
4155 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4158 /* We push args individually in reverse order, perform stack alignment
4159 before the first push (the last arg). */
4160 if (argblock == 0)
4161 anti_adjust_stack (GEN_INT (args_size.constant
4162 - original_args_size.constant));
4164 argnum = nargs - 1;
4166 #ifdef REG_PARM_STACK_SPACE
4167 if (ACCUMULATE_OUTGOING_ARGS)
4169 /* The argument list is the property of the called routine and it
4170 may clobber it. If the fixed area has been used for previous
4171 parameters, we must save and restore it. */
4172 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4173 &low_to_save, &high_to_save);
4175 #endif
4177 /* When expanding a normal call, args are stored in push order,
4178 which is the reverse of what we have here. */
4179 bool any_regs = false;
4180 for (int i = nargs; i-- > 0; )
4181 if (argvec[i].reg != NULL_RTX)
4183 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4184 any_regs = true;
4186 if (!any_regs)
4187 targetm.calls.call_args (pc_rtx, NULL_TREE);
4189 /* Push the args that need to be pushed. */
4191 have_push_fusage = false;
4193 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4194 are to be pushed. */
4195 for (count = 0; count < nargs; count++, argnum--)
4197 machine_mode mode = argvec[argnum].mode;
4198 rtx val = argvec[argnum].value;
4199 rtx reg = argvec[argnum].reg;
4200 int partial = argvec[argnum].partial;
4201 unsigned int parm_align = argvec[argnum].locate.boundary;
4202 int lower_bound = 0, upper_bound = 0, i;
4204 if (! (reg != 0 && partial == 0))
4206 rtx use;
4208 if (ACCUMULATE_OUTGOING_ARGS)
4210 /* If this is being stored into a pre-allocated, fixed-size,
4211 stack area, save any previous data at that location. */
4213 if (ARGS_GROW_DOWNWARD)
4215 /* stack_slot is negative, but we want to index stack_usage_map
4216 with positive values. */
4217 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4218 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4220 else
4222 lower_bound = argvec[argnum].locate.slot_offset.constant;
4223 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4226 i = lower_bound;
4227 /* Don't worry about things in the fixed argument area;
4228 it has already been saved. */
4229 if (i < reg_parm_stack_space)
4230 i = reg_parm_stack_space;
4231 while (i < upper_bound && stack_usage_map[i] == 0)
4232 i++;
4234 if (i < upper_bound)
4236 /* We need to make a save area. */
4237 unsigned int size
4238 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4239 machine_mode save_mode
4240 = mode_for_size (size, MODE_INT, 1);
4241 rtx adr
4242 = plus_constant (Pmode, argblock,
4243 argvec[argnum].locate.offset.constant);
4244 rtx stack_area
4245 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4247 if (save_mode == BLKmode)
4249 argvec[argnum].save_area
4250 = assign_stack_temp (BLKmode,
4251 argvec[argnum].locate.size.constant
4254 emit_block_move (validize_mem
4255 (copy_rtx (argvec[argnum].save_area)),
4256 stack_area,
4257 GEN_INT (argvec[argnum].locate.size.constant),
4258 BLOCK_OP_CALL_PARM);
4260 else
4262 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4264 emit_move_insn (argvec[argnum].save_area, stack_area);
4269 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4270 partial, reg, 0, argblock,
4271 GEN_INT (argvec[argnum].locate.offset.constant),
4272 reg_parm_stack_space,
4273 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4275 /* Now mark the segment we just used. */
4276 if (ACCUMULATE_OUTGOING_ARGS)
4277 for (i = lower_bound; i < upper_bound; i++)
4278 stack_usage_map[i] = 1;
4280 NO_DEFER_POP;
4282 /* Indicate argument access so that alias.c knows that these
4283 values are live. */
4284 if (argblock)
4285 use = plus_constant (Pmode, argblock,
4286 argvec[argnum].locate.offset.constant);
4287 else if (have_push_fusage)
4288 continue;
4289 else
4291 /* When arguments are pushed, trying to tell alias.c where
4292 exactly this argument is won't work, because the
4293 auto-increment causes confusion. So we merely indicate
4294 that we access something with a known mode somewhere on
4295 the stack. */
4296 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4297 gen_rtx_SCRATCH (Pmode));
4298 have_push_fusage = true;
4300 use = gen_rtx_MEM (argvec[argnum].mode, use);
4301 use = gen_rtx_USE (VOIDmode, use);
4302 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4306 argnum = nargs - 1;
4308 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4310 /* Now load any reg parms into their regs. */
4312 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4313 are to be pushed. */
4314 for (count = 0; count < nargs; count++, argnum--)
4316 machine_mode mode = argvec[argnum].mode;
4317 rtx val = argvec[argnum].value;
4318 rtx reg = argvec[argnum].reg;
4319 int partial = argvec[argnum].partial;
4320 #ifdef BLOCK_REG_PADDING
4321 int size = 0;
4322 #endif
4324 /* Handle calls that pass values in multiple non-contiguous
4325 locations. The PA64 has examples of this for library calls. */
4326 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4327 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4328 else if (reg != 0 && partial == 0)
4330 emit_move_insn (reg, val);
4331 #ifdef BLOCK_REG_PADDING
4332 size = GET_MODE_SIZE (argvec[argnum].mode);
4334 /* Copied from load_register_parameters. */
4336 /* Handle case where we have a value that needs shifting
4337 up to the msb. eg. a QImode value and we're padding
4338 upward on a BYTES_BIG_ENDIAN machine. */
4339 if (size < UNITS_PER_WORD
4340 && (argvec[argnum].locate.where_pad
4341 == (BYTES_BIG_ENDIAN ? upward : downward)))
4343 rtx x;
4344 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4346 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4347 report the whole reg as used. Strictly speaking, the
4348 call only uses SIZE bytes at the msb end, but it doesn't
4349 seem worth generating rtl to say that. */
4350 reg = gen_rtx_REG (word_mode, REGNO (reg));
4351 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4352 if (x != reg)
4353 emit_move_insn (reg, x);
4355 #endif
4358 NO_DEFER_POP;
4361 /* Any regs containing parms remain in use through the call. */
4362 for (count = 0; count < nargs; count++)
4364 rtx reg = argvec[count].reg;
4365 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4366 use_group_regs (&call_fusage, reg);
4367 else if (reg != 0)
4369 int partial = argvec[count].partial;
4370 if (partial)
4372 int nregs;
4373 gcc_assert (partial % UNITS_PER_WORD == 0);
4374 nregs = partial / UNITS_PER_WORD;
4375 use_regs (&call_fusage, REGNO (reg), nregs);
4377 else
4378 use_reg (&call_fusage, reg);
4382 /* Pass the function the address in which to return a structure value. */
4383 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4385 emit_move_insn (struct_value,
4386 force_reg (Pmode,
4387 force_operand (XEXP (mem_value, 0),
4388 NULL_RTX)));
4389 if (REG_P (struct_value))
4390 use_reg (&call_fusage, struct_value);
4393 /* Don't allow popping to be deferred, since then
4394 cse'ing of library calls could delete a call and leave the pop. */
4395 NO_DEFER_POP;
4396 valreg = (mem_value == 0 && outmode != VOIDmode
4397 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4399 /* Stack must be properly aligned now. */
4400 gcc_assert (!(stack_pointer_delta
4401 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4403 before_call = get_last_insn ();
4405 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4406 will set inhibit_defer_pop to that value. */
4407 /* The return type is needed to decide how many bytes the function pops.
4408 Signedness plays no role in that, so for simplicity, we pretend it's
4409 always signed. We also assume that the list of arguments passed has
4410 no impact, so we pretend it is unknown. */
4412 emit_call_1 (fun, NULL,
4413 get_identifier (XSTR (orgfun, 0)),
4414 build_function_type (tfom, NULL_TREE),
4415 original_args_size.constant, args_size.constant,
4416 struct_value_size,
4417 targetm.calls.function_arg (args_so_far,
4418 VOIDmode, void_type_node, true),
4419 valreg,
4420 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4422 if (flag_ipa_ra)
4424 rtx datum = orgfun;
4425 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4426 rtx_call_insn *last = last_call_insn ();
4427 add_reg_note (last, REG_CALL_DECL, datum);
4430 /* Right-shift returned value if necessary. */
4431 if (!pcc_struct_value
4432 && TYPE_MODE (tfom) != BLKmode
4433 && targetm.calls.return_in_msb (tfom))
4435 shift_return_value (TYPE_MODE (tfom), false, valreg);
4436 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4439 targetm.calls.end_call_args ();
4441 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4442 that it should complain if nonvolatile values are live. For
4443 functions that cannot return, inform flow that control does not
4444 fall through. */
4445 if (flags & ECF_NORETURN)
4447 /* The barrier note must be emitted
4448 immediately after the CALL_INSN. Some ports emit more than
4449 just a CALL_INSN above, so we must search for it here. */
4450 rtx_insn *last = get_last_insn ();
4451 while (!CALL_P (last))
4453 last = PREV_INSN (last);
4454 /* There was no CALL_INSN? */
4455 gcc_assert (last != before_call);
4458 emit_barrier_after (last);
4461 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
4462 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
4463 if (flags & ECF_NOTHROW)
4465 rtx_insn *last = get_last_insn ();
4466 while (!CALL_P (last))
4468 last = PREV_INSN (last);
4469 /* There was no CALL_INSN? */
4470 gcc_assert (last != before_call);
4473 make_reg_eh_region_note_nothrow_nononlocal (last);
4476 /* Now restore inhibit_defer_pop to its actual original value. */
4477 OK_DEFER_POP;
4479 pop_temp_slots ();
4481 /* Copy the value to the right place. */
4482 if (outmode != VOIDmode && retval)
4484 if (mem_value)
4486 if (value == 0)
4487 value = mem_value;
4488 if (value != mem_value)
4489 emit_move_insn (value, mem_value);
4491 else if (GET_CODE (valreg) == PARALLEL)
4493 if (value == 0)
4494 value = gen_reg_rtx (outmode);
4495 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4497 else
4499 /* Convert to the proper mode if a promotion has been active. */
4500 if (GET_MODE (valreg) != outmode)
4502 int unsignedp = TYPE_UNSIGNED (tfom);
4504 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4505 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4506 == GET_MODE (valreg));
4507 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4510 if (value != 0)
4511 emit_move_insn (value, valreg);
4512 else
4513 value = valreg;
4517 if (ACCUMULATE_OUTGOING_ARGS)
4519 #ifdef REG_PARM_STACK_SPACE
4520 if (save_area)
4521 restore_fixed_argument_area (save_area, argblock,
4522 high_to_save, low_to_save);
4523 #endif
4525 /* If we saved any argument areas, restore them. */
4526 for (count = 0; count < nargs; count++)
4527 if (argvec[count].save_area)
4529 machine_mode save_mode = GET_MODE (argvec[count].save_area);
4530 rtx adr = plus_constant (Pmode, argblock,
4531 argvec[count].locate.offset.constant);
4532 rtx stack_area = gen_rtx_MEM (save_mode,
4533 memory_address (save_mode, adr));
4535 if (save_mode == BLKmode)
4536 emit_block_move (stack_area,
4537 validize_mem
4538 (copy_rtx (argvec[count].save_area)),
4539 GEN_INT (argvec[count].locate.size.constant),
4540 BLOCK_OP_CALL_PARM);
4541 else
4542 emit_move_insn (stack_area, argvec[count].save_area);
4545 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4546 stack_usage_map = initial_stack_usage_map;
4549 free (stack_usage_map_buf);
4551 return value;
4555 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4556 (emitting the queue unless NO_QUEUE is nonzero),
4557 for a value of mode OUTMODE,
4558 with NARGS different arguments, passed as alternating rtx values
4559 and machine_modes to convert them to.
4561 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4562 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4563 other types of library calls. */
4565 void
4566 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4567 machine_mode outmode, int nargs, ...)
4569 va_list p;
4571 va_start (p, nargs);
4572 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4573 va_end (p);
4576 /* Like emit_library_call except that an extra argument, VALUE,
4577 comes second and says where to store the result.
4578 (If VALUE is zero, this function chooses a convenient way
4579 to return the value.
4581 This function returns an rtx for where the value is to be found.
4582 If VALUE is nonzero, VALUE is returned. */
4585 emit_library_call_value (rtx orgfun, rtx value,
4586 enum libcall_type fn_type,
4587 machine_mode outmode, int nargs, ...)
4589 rtx result;
4590 va_list p;
4592 va_start (p, nargs);
4593 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4594 nargs, p);
4595 va_end (p);
4597 return result;
4601 /* Store pointer bounds argument ARG into Bounds Table entry
4602 associated with PARM. */
4603 static void
4604 store_bounds (struct arg_data *arg, struct arg_data *parm)
4606 rtx slot = NULL, ptr = NULL, addr = NULL;
4608 /* We may pass bounds not associated with any pointer. */
4609 if (!parm)
4611 gcc_assert (arg->special_slot);
4612 slot = arg->special_slot;
4613 ptr = const0_rtx;
4615 /* Find pointer associated with bounds and where it is
4616 passed. */
4617 else
4619 if (!parm->reg)
4621 gcc_assert (!arg->special_slot);
4623 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
4625 else if (REG_P (parm->reg))
4627 gcc_assert (arg->special_slot);
4628 slot = arg->special_slot;
4630 if (MEM_P (parm->value))
4631 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
4632 else if (REG_P (parm->value))
4633 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
4634 else
4636 gcc_assert (!arg->pointer_offset);
4637 ptr = parm->value;
4640 else
4642 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
4644 gcc_assert (arg->special_slot);
4645 slot = arg->special_slot;
4647 if (parm->parallel_value)
4648 ptr = chkp_get_value_with_offs (parm->parallel_value,
4649 GEN_INT (arg->pointer_offset));
4650 else
4651 gcc_unreachable ();
4655 /* Expand bounds. */
4656 if (!arg->value)
4657 arg->value = expand_normal (arg->tree_value);
4659 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
4662 /* Store a single argument for a function call
4663 into the register or memory area where it must be passed.
4664 *ARG describes the argument value and where to pass it.
4666 ARGBLOCK is the address of the stack-block for all the arguments,
4667 or 0 on a machine where arguments are pushed individually.
4669 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4670 so must be careful about how the stack is used.
4672 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4673 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4674 that we need not worry about saving and restoring the stack.
4676 FNDECL is the declaration of the function we are calling.
4678 Return nonzero if this arg should cause sibcall failure,
4679 zero otherwise. */
4681 static int
4682 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4683 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4685 tree pval = arg->tree_value;
4686 rtx reg = 0;
4687 int partial = 0;
4688 int used = 0;
4689 int i, lower_bound = 0, upper_bound = 0;
4690 int sibcall_failure = 0;
4692 if (TREE_CODE (pval) == ERROR_MARK)
4693 return 1;
4695 /* Push a new temporary level for any temporaries we make for
4696 this argument. */
4697 push_temp_slots ();
4699 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4701 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4702 save any previous data at that location. */
4703 if (argblock && ! variable_size && arg->stack)
4705 if (ARGS_GROW_DOWNWARD)
4707 /* stack_slot is negative, but we want to index stack_usage_map
4708 with positive values. */
4709 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4710 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4711 else
4712 upper_bound = 0;
4714 lower_bound = upper_bound - arg->locate.size.constant;
4716 else
4718 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4719 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4720 else
4721 lower_bound = 0;
4723 upper_bound = lower_bound + arg->locate.size.constant;
4726 i = lower_bound;
4727 /* Don't worry about things in the fixed argument area;
4728 it has already been saved. */
4729 if (i < reg_parm_stack_space)
4730 i = reg_parm_stack_space;
4731 while (i < upper_bound && stack_usage_map[i] == 0)
4732 i++;
4734 if (i < upper_bound)
4736 /* We need to make a save area. */
4737 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4738 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4739 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4740 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4742 if (save_mode == BLKmode)
4744 arg->save_area
4745 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
4746 preserve_temp_slots (arg->save_area);
4747 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
4748 stack_area,
4749 GEN_INT (arg->locate.size.constant),
4750 BLOCK_OP_CALL_PARM);
4752 else
4754 arg->save_area = gen_reg_rtx (save_mode);
4755 emit_move_insn (arg->save_area, stack_area);
4761 /* If this isn't going to be placed on both the stack and in registers,
4762 set up the register and number of words. */
4763 if (! arg->pass_on_stack)
4765 if (flags & ECF_SIBCALL)
4766 reg = arg->tail_call_reg;
4767 else
4768 reg = arg->reg;
4769 partial = arg->partial;
4772 /* Being passed entirely in a register. We shouldn't be called in
4773 this case. */
4774 gcc_assert (reg == 0 || partial != 0);
4776 /* If this arg needs special alignment, don't load the registers
4777 here. */
4778 if (arg->n_aligned_regs != 0)
4779 reg = 0;
4781 /* If this is being passed partially in a register, we can't evaluate
4782 it directly into its stack slot. Otherwise, we can. */
4783 if (arg->value == 0)
4785 /* stack_arg_under_construction is nonzero if a function argument is
4786 being evaluated directly into the outgoing argument list and
4787 expand_call must take special action to preserve the argument list
4788 if it is called recursively.
4790 For scalar function arguments stack_usage_map is sufficient to
4791 determine which stack slots must be saved and restored. Scalar
4792 arguments in general have pass_on_stack == 0.
4794 If this argument is initialized by a function which takes the
4795 address of the argument (a C++ constructor or a C function
4796 returning a BLKmode structure), then stack_usage_map is
4797 insufficient and expand_call must push the stack around the
4798 function call. Such arguments have pass_on_stack == 1.
4800 Note that it is always safe to set stack_arg_under_construction,
4801 but this generates suboptimal code if set when not needed. */
4803 if (arg->pass_on_stack)
4804 stack_arg_under_construction++;
4806 arg->value = expand_expr (pval,
4807 (partial
4808 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4809 ? NULL_RTX : arg->stack,
4810 VOIDmode, EXPAND_STACK_PARM);
4812 /* If we are promoting object (or for any other reason) the mode
4813 doesn't agree, convert the mode. */
4815 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4816 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4817 arg->value, arg->unsignedp);
4819 if (arg->pass_on_stack)
4820 stack_arg_under_construction--;
4823 /* Check for overlap with already clobbered argument area. */
4824 if ((flags & ECF_SIBCALL)
4825 && MEM_P (arg->value)
4826 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4827 arg->locate.size.constant))
4828 sibcall_failure = 1;
4830 /* Don't allow anything left on stack from computation
4831 of argument to alloca. */
4832 if (flags & ECF_MAY_BE_ALLOCA)
4833 do_pending_stack_adjust ();
4835 if (arg->value == arg->stack)
4836 /* If the value is already in the stack slot, we are done. */
4838 else if (arg->mode != BLKmode)
4840 int size;
4841 unsigned int parm_align;
4843 /* Argument is a scalar, not entirely passed in registers.
4844 (If part is passed in registers, arg->partial says how much
4845 and emit_push_insn will take care of putting it there.)
4847 Push it, and if its size is less than the
4848 amount of space allocated to it,
4849 also bump stack pointer by the additional space.
4850 Note that in C the default argument promotions
4851 will prevent such mismatches. */
4853 size = GET_MODE_SIZE (arg->mode);
4854 /* Compute how much space the push instruction will push.
4855 On many machines, pushing a byte will advance the stack
4856 pointer by a halfword. */
4857 #ifdef PUSH_ROUNDING
4858 size = PUSH_ROUNDING (size);
4859 #endif
4860 used = size;
4862 /* Compute how much space the argument should get:
4863 round up to a multiple of the alignment for arguments. */
4864 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4865 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4866 / (PARM_BOUNDARY / BITS_PER_UNIT))
4867 * (PARM_BOUNDARY / BITS_PER_UNIT));
4869 /* Compute the alignment of the pushed argument. */
4870 parm_align = arg->locate.boundary;
4871 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4873 int pad = used - size;
4874 if (pad)
4876 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4877 parm_align = MIN (parm_align, pad_align);
4881 /* This isn't already where we want it on the stack, so put it there.
4882 This can either be done with push or copy insns. */
4883 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4884 parm_align, partial, reg, used - size, argblock,
4885 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4886 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
4887 sibcall_failure = 1;
4889 /* Unless this is a partially-in-register argument, the argument is now
4890 in the stack. */
4891 if (partial == 0)
4892 arg->value = arg->stack;
4894 else
4896 /* BLKmode, at least partly to be pushed. */
4898 unsigned int parm_align;
4899 int excess;
4900 rtx size_rtx;
4902 /* Pushing a nonscalar.
4903 If part is passed in registers, PARTIAL says how much
4904 and emit_push_insn will take care of putting it there. */
4906 /* Round its size up to a multiple
4907 of the allocation unit for arguments. */
4909 if (arg->locate.size.var != 0)
4911 excess = 0;
4912 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4914 else
4916 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4917 for BLKmode is careful to avoid it. */
4918 excess = (arg->locate.size.constant
4919 - int_size_in_bytes (TREE_TYPE (pval))
4920 + partial);
4921 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4922 NULL_RTX, TYPE_MODE (sizetype),
4923 EXPAND_NORMAL);
4926 parm_align = arg->locate.boundary;
4928 /* When an argument is padded down, the block is aligned to
4929 PARM_BOUNDARY, but the actual argument isn't. */
4930 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4932 if (arg->locate.size.var)
4933 parm_align = BITS_PER_UNIT;
4934 else if (excess)
4936 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4937 parm_align = MIN (parm_align, excess_align);
4941 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4943 /* emit_push_insn might not work properly if arg->value and
4944 argblock + arg->locate.offset areas overlap. */
4945 rtx x = arg->value;
4946 int i = 0;
4948 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4949 || (GET_CODE (XEXP (x, 0)) == PLUS
4950 && XEXP (XEXP (x, 0), 0) ==
4951 crtl->args.internal_arg_pointer
4952 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4954 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4955 i = INTVAL (XEXP (XEXP (x, 0), 1));
4957 /* arg.locate doesn't contain the pretend_args_size offset,
4958 it's part of argblock. Ensure we don't count it in I. */
4959 if (STACK_GROWS_DOWNWARD)
4960 i -= crtl->args.pretend_args_size;
4961 else
4962 i += crtl->args.pretend_args_size;
4964 /* expand_call should ensure this. */
4965 gcc_assert (!arg->locate.offset.var
4966 && arg->locate.size.var == 0
4967 && CONST_INT_P (size_rtx));
4969 if (arg->locate.offset.constant > i)
4971 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4972 sibcall_failure = 1;
4974 else if (arg->locate.offset.constant < i)
4976 /* Use arg->locate.size.constant instead of size_rtx
4977 because we only care about the part of the argument
4978 on the stack. */
4979 if (i < (arg->locate.offset.constant
4980 + arg->locate.size.constant))
4981 sibcall_failure = 1;
4983 else
4985 /* Even though they appear to be at the same location,
4986 if part of the outgoing argument is in registers,
4987 they aren't really at the same location. Check for
4988 this by making sure that the incoming size is the
4989 same as the outgoing size. */
4990 if (arg->locate.size.constant != INTVAL (size_rtx))
4991 sibcall_failure = 1;
4996 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4997 parm_align, partial, reg, excess, argblock,
4998 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4999 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5001 /* Unless this is a partially-in-register argument, the argument is now
5002 in the stack.
5004 ??? Unlike the case above, in which we want the actual
5005 address of the data, so that we can load it directly into a
5006 register, here we want the address of the stack slot, so that
5007 it's properly aligned for word-by-word copying or something
5008 like that. It's not clear that this is always correct. */
5009 if (partial == 0)
5010 arg->value = arg->stack_slot;
5013 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5015 tree type = TREE_TYPE (arg->tree_value);
5016 arg->parallel_value
5017 = emit_group_load_into_temps (arg->reg, arg->value, type,
5018 int_size_in_bytes (type));
5021 /* Mark all slots this store used. */
5022 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5023 && argblock && ! variable_size && arg->stack)
5024 for (i = lower_bound; i < upper_bound; i++)
5025 stack_usage_map[i] = 1;
5027 /* Once we have pushed something, pops can't safely
5028 be deferred during the rest of the arguments. */
5029 NO_DEFER_POP;
5031 /* Free any temporary slots made in processing this argument. */
5032 pop_temp_slots ();
5034 return sibcall_failure;
5037 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5039 bool
5040 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5041 const_tree type)
5043 if (!type)
5044 return false;
5046 /* If the type has variable size... */
5047 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5048 return true;
5050 /* If the type is marked as addressable (it is required
5051 to be constructed into the stack)... */
5052 if (TREE_ADDRESSABLE (type))
5053 return true;
5055 return false;
5058 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5059 takes trailing padding of a structure into account. */
5060 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5062 bool
5063 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5065 if (!type)
5066 return false;
5068 /* If the type has variable size... */
5069 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5070 return true;
5072 /* If the type is marked as addressable (it is required
5073 to be constructed into the stack)... */
5074 if (TREE_ADDRESSABLE (type))
5075 return true;
5077 /* If the padding and mode of the type is such that a copy into
5078 a register would put it into the wrong part of the register. */
5079 if (mode == BLKmode
5080 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5081 && (FUNCTION_ARG_PADDING (mode, type)
5082 == (BYTES_BIG_ENDIAN ? upward : downward)))
5083 return true;
5085 return false;