PR middle-end/66314
[official-gcc.git] / gcc / calls.c
blob563672512beea3b448d8d552c0208036dc06f8bd
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2015 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 "predict.h"
25 #include "tree.h"
26 #include "gimple.h"
27 #include "rtl.h"
28 #include "alias.h"
29 #include "fold-const.h"
30 #include "stor-layout.h"
31 #include "varasm.h"
32 #include "stringpool.h"
33 #include "attribs.h"
34 #include "internal-fn.h"
35 #include "flags.h"
36 #include "insn-config.h"
37 #include "expmed.h"
38 #include "dojump.h"
39 #include "explow.h"
40 #include "calls.h"
41 #include "emit-rtl.h"
42 #include "stmt.h"
43 #include "expr.h"
44 #include "insn-codes.h"
45 #include "optabs.h"
46 #include "libfuncs.h"
47 #include "regs.h"
48 #include "diagnostic-core.h"
49 #include "output.h"
50 #include "tm_p.h"
51 #include "timevar.h"
52 #include "langhooks.h"
53 #include "target.h"
54 #include "cgraph.h"
55 #include "except.h"
56 #include "dbgcnt.h"
57 #include "rtl-iter.h"
58 #include "tree-chkp.h"
59 #include "rtl-chkp.h"
62 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
63 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
65 /* Data structure and subroutines used within expand_call. */
67 struct arg_data
69 /* Tree node for this argument. */
70 tree tree_value;
71 /* Mode for value; TYPE_MODE unless promoted. */
72 machine_mode mode;
73 /* Current RTL value for argument, or 0 if it isn't precomputed. */
74 rtx value;
75 /* Initially-compute RTL value for argument; only for const functions. */
76 rtx initial_value;
77 /* Register to pass this argument in, 0 if passed on stack, or an
78 PARALLEL if the arg is to be copied into multiple non-contiguous
79 registers. */
80 rtx reg;
81 /* Register to pass this argument in when generating tail call sequence.
82 This is not the same register as for normal calls on machines with
83 register windows. */
84 rtx tail_call_reg;
85 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
86 form for emit_group_move. */
87 rtx parallel_value;
88 /* If value is passed in neither reg nor stack, this field holds a number
89 of a special slot to be used. */
90 rtx special_slot;
91 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
92 there is no such pointer. */
93 int pointer_arg;
94 /* If pointer_arg refers a structure, then pointer_offset holds an offset
95 of a pointer in this structure. */
96 int pointer_offset;
97 /* If REG was promoted from the actual mode of the argument expression,
98 indicates whether the promotion is sign- or zero-extended. */
99 int unsignedp;
100 /* Number of bytes to put in registers. 0 means put the whole arg
101 in registers. Also 0 if not passed in registers. */
102 int partial;
103 /* Nonzero if argument must be passed on stack.
104 Note that some arguments may be passed on the stack
105 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
106 pass_on_stack identifies arguments that *cannot* go in registers. */
107 int pass_on_stack;
108 /* Some fields packaged up for locate_and_pad_parm. */
109 struct locate_and_pad_arg_data locate;
110 /* Location on the stack at which parameter should be stored. The store
111 has already been done if STACK == VALUE. */
112 rtx stack;
113 /* Location on the stack of the start of this argument slot. This can
114 differ from STACK if this arg pads downward. This location is known
115 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
116 rtx stack_slot;
117 /* Place that this stack area has been saved, if needed. */
118 rtx save_area;
119 /* If an argument's alignment does not permit direct copying into registers,
120 copy in smaller-sized pieces into pseudos. These are stored in a
121 block pointed to by this field. The next field says how many
122 word-sized pseudos we made. */
123 rtx *aligned_regs;
124 int n_aligned_regs;
127 /* A vector of one char per byte of stack space. A byte if nonzero if
128 the corresponding stack location has been used.
129 This vector is used to prevent a function call within an argument from
130 clobbering any stack already set up. */
131 static char *stack_usage_map;
133 /* Size of STACK_USAGE_MAP. */
134 static int highest_outgoing_arg_in_use;
136 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
137 stack location's tail call argument has been already stored into the stack.
138 This bitmap is used to prevent sibling call optimization if function tries
139 to use parent's incoming argument slots when they have been already
140 overwritten with tail call arguments. */
141 static sbitmap stored_args_map;
143 /* stack_arg_under_construction is nonzero when an argument may be
144 initialized with a constructor call (including a C function that
145 returns a BLKmode struct) and expand_call must take special action
146 to make sure the object being constructed does not overlap the
147 argument list for the constructor call. */
148 static int stack_arg_under_construction;
150 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
151 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
152 cumulative_args_t);
153 static void precompute_register_parameters (int, struct arg_data *, int *);
154 static void store_bounds (struct arg_data *, struct arg_data *);
155 static int store_one_arg (struct arg_data *, rtx, int, int, int);
156 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
157 static int finalize_must_preallocate (int, int, struct arg_data *,
158 struct args_size *);
159 static void precompute_arguments (int, struct arg_data *);
160 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
161 static void initialize_argument_information (int, struct arg_data *,
162 struct args_size *, int,
163 tree, tree,
164 tree, tree, cumulative_args_t, int,
165 rtx *, int *, int *, int *,
166 bool *, bool);
167 static void compute_argument_addresses (struct arg_data *, rtx, int);
168 static rtx rtx_for_function_call (tree, tree);
169 static void load_register_parameters (struct arg_data *, int, rtx *, int,
170 int, int *);
171 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
172 machine_mode, int, va_list);
173 static int special_function_p (const_tree, int);
174 static int check_sibcall_argument_overlap_1 (rtx);
175 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
177 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
178 unsigned int);
179 static tree split_complex_types (tree);
181 #ifdef REG_PARM_STACK_SPACE
182 static rtx save_fixed_argument_area (int, rtx, int *, int *);
183 static void restore_fixed_argument_area (rtx, rtx, int, int);
184 #endif
186 /* Force FUNEXP into a form suitable for the address of a CALL,
187 and return that as an rtx. Also load the static chain register
188 if FNDECL is a nested function.
190 CALL_FUSAGE points to a variable holding the prospective
191 CALL_INSN_FUNCTION_USAGE information. */
194 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
195 rtx *call_fusage, int reg_parm_seen, int sibcallp)
197 /* Make a valid memory address and copy constants through pseudo-regs,
198 but not for a constant address if -fno-function-cse. */
199 if (GET_CODE (funexp) != SYMBOL_REF)
200 /* If we are using registers for parameters, force the
201 function address into a register now. */
202 funexp = ((reg_parm_seen
203 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
204 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
205 : memory_address (FUNCTION_MODE, funexp));
206 else if (flag_pic
207 && fndecl_or_type
208 && TREE_CODE (fndecl_or_type) == FUNCTION_DECL
209 && (!flag_plt
210 || lookup_attribute ("noplt", DECL_ATTRIBUTES (fndecl_or_type)))
211 && !targetm.binds_local_p (fndecl_or_type))
213 /* This is done only for PIC code. There is no easy interface to force the
214 function address into GOT for non-PIC case. non-PIC case needs to be
215 handled specially by the backend. */
216 funexp = force_reg (Pmode, funexp);
218 else if (! sibcallp)
220 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
221 funexp = force_reg (Pmode, funexp);
224 if (static_chain_value != 0
225 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
226 || DECL_STATIC_CHAIN (fndecl_or_type)))
228 rtx chain;
230 chain = targetm.calls.static_chain (fndecl_or_type, false);
231 static_chain_value = convert_memory_address (Pmode, static_chain_value);
233 emit_move_insn (chain, static_chain_value);
234 if (REG_P (chain))
235 use_reg (call_fusage, chain);
238 return funexp;
241 /* Generate instructions to call function FUNEXP,
242 and optionally pop the results.
243 The CALL_INSN is the first insn generated.
245 FNDECL is the declaration node of the function. This is given to the
246 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
247 its own args.
249 FUNTYPE is the data type of the function. This is given to the hook
250 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
251 own args. We used to allow an identifier for library functions, but
252 that doesn't work when the return type is an aggregate type and the
253 calling convention says that the pointer to this aggregate is to be
254 popped by the callee.
256 STACK_SIZE is the number of bytes of arguments on the stack,
257 ROUNDED_STACK_SIZE is that number rounded up to
258 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
259 both to put into the call insn and to generate explicit popping
260 code if necessary.
262 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
263 It is zero if this call doesn't want a structure value.
265 NEXT_ARG_REG is the rtx that results from executing
266 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
267 just after all the args have had their registers assigned.
268 This could be whatever you like, but normally it is the first
269 arg-register beyond those used for args in this call,
270 or 0 if all the arg-registers are used in this call.
271 It is passed on to `gen_call' so you can put this info in the call insn.
273 VALREG is a hard register in which a value is returned,
274 or 0 if the call does not return a value.
276 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
277 the args to this call were processed.
278 We restore `inhibit_defer_pop' to that value.
280 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
281 denote registers used by the called function. */
283 static void
284 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
285 tree funtype ATTRIBUTE_UNUSED,
286 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
287 HOST_WIDE_INT rounded_stack_size,
288 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
289 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
290 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
291 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
293 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
294 rtx call, funmem;
295 int already_popped = 0;
296 HOST_WIDE_INT n_popped
297 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
299 #ifdef CALL_POPS_ARGS
300 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
301 #endif
303 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
304 and we don't want to load it into a register as an optimization,
305 because prepare_call_address already did it if it should be done. */
306 if (GET_CODE (funexp) != SYMBOL_REF)
307 funexp = memory_address (FUNCTION_MODE, funexp);
309 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
310 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
312 tree t = fndecl;
314 /* Although a built-in FUNCTION_DECL and its non-__builtin
315 counterpart compare equal and get a shared mem_attrs, they
316 produce different dump output in compare-debug compilations,
317 if an entry gets garbage collected in one compilation, then
318 adds a different (but equivalent) entry, while the other
319 doesn't run the garbage collector at the same spot and then
320 shares the mem_attr with the equivalent entry. */
321 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
323 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
324 if (t2)
325 t = t2;
328 set_mem_expr (funmem, t);
330 else if (fntree)
331 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
333 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
334 if ((ecf_flags & ECF_SIBCALL)
335 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
336 && (n_popped > 0 || stack_size == 0))
338 rtx n_pop = GEN_INT (n_popped);
339 rtx pat;
341 /* If this subroutine pops its own args, record that in the call insn
342 if possible, for the sake of frame pointer elimination. */
344 if (valreg)
345 pat = GEN_SIBCALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
346 next_arg_reg, n_pop);
347 else
348 pat = GEN_SIBCALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
349 n_pop);
351 emit_call_insn (pat);
352 already_popped = 1;
354 else
355 #endif
357 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
358 /* If the target has "call" or "call_value" insns, then prefer them
359 if no arguments are actually popped. If the target does not have
360 "call" or "call_value" insns, then we must use the popping versions
361 even if the call has no arguments to pop. */
362 #if defined (HAVE_call) && defined (HAVE_call_value)
363 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
364 && n_popped > 0)
365 #else
366 if (HAVE_call_pop && HAVE_call_value_pop)
367 #endif
369 rtx n_pop = GEN_INT (n_popped);
370 rtx pat;
372 /* If this subroutine pops its own args, record that in the call insn
373 if possible, for the sake of frame pointer elimination. */
375 if (valreg)
376 pat = GEN_CALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
377 next_arg_reg, n_pop);
378 else
379 pat = GEN_CALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
380 n_pop);
382 emit_call_insn (pat);
383 already_popped = 1;
385 else
386 #endif
388 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
389 if ((ecf_flags & ECF_SIBCALL)
390 && HAVE_sibcall && HAVE_sibcall_value)
392 if (valreg)
393 emit_call_insn (GEN_SIBCALL_VALUE (valreg, funmem,
394 rounded_stack_size_rtx,
395 next_arg_reg, NULL_RTX));
396 else
397 emit_call_insn (GEN_SIBCALL (funmem, rounded_stack_size_rtx,
398 next_arg_reg,
399 GEN_INT (struct_value_size)));
401 else
402 #endif
404 #if defined (HAVE_call) && defined (HAVE_call_value)
405 if (HAVE_call && HAVE_call_value)
407 if (valreg)
408 emit_call_insn (GEN_CALL_VALUE (valreg, funmem, rounded_stack_size_rtx,
409 next_arg_reg, NULL_RTX));
410 else
411 emit_call_insn (GEN_CALL (funmem, rounded_stack_size_rtx, next_arg_reg,
412 GEN_INT (struct_value_size)));
414 else
415 #endif
416 gcc_unreachable ();
418 /* Find the call we just emitted. */
419 rtx_call_insn *call_insn = last_call_insn ();
421 /* Some target create a fresh MEM instead of reusing the one provided
422 above. Set its MEM_EXPR. */
423 call = get_call_rtx_from (call_insn);
424 if (call
425 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
426 && MEM_EXPR (funmem) != NULL_TREE)
427 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
429 /* Mark instrumented calls. */
430 if (call && fntree)
431 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
433 /* Put the register usage information there. */
434 add_function_usage_to (call_insn, call_fusage);
436 /* If this is a const call, then set the insn's unchanging bit. */
437 if (ecf_flags & ECF_CONST)
438 RTL_CONST_CALL_P (call_insn) = 1;
440 /* If this is a pure call, then set the insn's unchanging bit. */
441 if (ecf_flags & ECF_PURE)
442 RTL_PURE_CALL_P (call_insn) = 1;
444 /* If this is a const call, then set the insn's unchanging bit. */
445 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
446 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
448 /* Create a nothrow REG_EH_REGION note, if needed. */
449 make_reg_eh_region_note (call_insn, ecf_flags, 0);
451 if (ecf_flags & ECF_NORETURN)
452 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
454 if (ecf_flags & ECF_RETURNS_TWICE)
456 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
457 cfun->calls_setjmp = 1;
460 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
462 /* Restore this now, so that we do defer pops for this call's args
463 if the context of the call as a whole permits. */
464 inhibit_defer_pop = old_inhibit_defer_pop;
466 if (n_popped > 0)
468 if (!already_popped)
469 CALL_INSN_FUNCTION_USAGE (call_insn)
470 = gen_rtx_EXPR_LIST (VOIDmode,
471 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
472 CALL_INSN_FUNCTION_USAGE (call_insn));
473 rounded_stack_size -= n_popped;
474 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
475 stack_pointer_delta -= n_popped;
477 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
479 /* If popup is needed, stack realign must use DRAP */
480 if (SUPPORTS_STACK_ALIGNMENT)
481 crtl->need_drap = true;
483 /* For noreturn calls when not accumulating outgoing args force
484 REG_ARGS_SIZE note to prevent crossjumping of calls with different
485 args sizes. */
486 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
487 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
489 if (!ACCUMULATE_OUTGOING_ARGS)
491 /* If returning from the subroutine does not automatically pop the args,
492 we need an instruction to pop them sooner or later.
493 Perhaps do it now; perhaps just record how much space to pop later.
495 If returning from the subroutine does pop the args, indicate that the
496 stack pointer will be changed. */
498 if (rounded_stack_size != 0)
500 if (ecf_flags & ECF_NORETURN)
501 /* Just pretend we did the pop. */
502 stack_pointer_delta -= rounded_stack_size;
503 else if (flag_defer_pop && inhibit_defer_pop == 0
504 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
505 pending_stack_adjust += rounded_stack_size;
506 else
507 adjust_stack (rounded_stack_size_rtx);
510 /* When we accumulate outgoing args, we must avoid any stack manipulations.
511 Restore the stack pointer to its original value now. Usually
512 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
513 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
514 popping variants of functions exist as well.
516 ??? We may optimize similar to defer_pop above, but it is
517 probably not worthwhile.
519 ??? It will be worthwhile to enable combine_stack_adjustments even for
520 such machines. */
521 else if (n_popped)
522 anti_adjust_stack (GEN_INT (n_popped));
525 /* Determine if the function identified by NAME and FNDECL is one with
526 special properties we wish to know about.
528 For example, if the function might return more than one time (setjmp), then
529 set RETURNS_TWICE to a nonzero value.
531 Similarly set NORETURN if the function is in the longjmp family.
533 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
534 space from the stack such as alloca. */
536 static int
537 special_function_p (const_tree fndecl, int flags)
539 tree name_decl = DECL_NAME (fndecl);
541 /* For instrumentation clones we want to derive flags
542 from the original name. */
543 if (cgraph_node::get (fndecl)
544 && cgraph_node::get (fndecl)->instrumentation_clone)
545 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
547 if (fndecl && name_decl
548 && IDENTIFIER_LENGTH (name_decl) <= 17
549 /* Exclude functions not at the file scope, or not `extern',
550 since they are not the magic functions we would otherwise
551 think they are.
552 FIXME: this should be handled with attributes, not with this
553 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
554 because you can declare fork() inside a function if you
555 wish. */
556 && (DECL_CONTEXT (fndecl) == NULL_TREE
557 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
558 && TREE_PUBLIC (fndecl))
560 const char *name = IDENTIFIER_POINTER (name_decl);
561 const char *tname = name;
563 /* We assume that alloca will always be called by name. It
564 makes no sense to pass it as a pointer-to-function to
565 anything that does not understand its behavior. */
566 if (((IDENTIFIER_LENGTH (name_decl) == 6
567 && name[0] == 'a'
568 && ! strcmp (name, "alloca"))
569 || (IDENTIFIER_LENGTH (name_decl) == 16
570 && name[0] == '_'
571 && ! strcmp (name, "__builtin_alloca"))))
572 flags |= ECF_MAY_BE_ALLOCA;
574 /* Disregard prefix _, __, __x or __builtin_. */
575 if (name[0] == '_')
577 if (name[1] == '_'
578 && name[2] == 'b'
579 && !strncmp (name + 3, "uiltin_", 7))
580 tname += 10;
581 else if (name[1] == '_' && name[2] == 'x')
582 tname += 3;
583 else if (name[1] == '_')
584 tname += 2;
585 else
586 tname += 1;
589 if (tname[0] == 's')
591 if ((tname[1] == 'e'
592 && (! strcmp (tname, "setjmp")
593 || ! strcmp (tname, "setjmp_syscall")))
594 || (tname[1] == 'i'
595 && ! strcmp (tname, "sigsetjmp"))
596 || (tname[1] == 'a'
597 && ! strcmp (tname, "savectx")))
598 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
600 if (tname[1] == 'i'
601 && ! strcmp (tname, "siglongjmp"))
602 flags |= ECF_NORETURN;
604 else if ((tname[0] == 'q' && tname[1] == 's'
605 && ! strcmp (tname, "qsetjmp"))
606 || (tname[0] == 'v' && tname[1] == 'f'
607 && ! strcmp (tname, "vfork"))
608 || (tname[0] == 'g' && tname[1] == 'e'
609 && !strcmp (tname, "getcontext")))
610 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
612 else if (tname[0] == 'l' && tname[1] == 'o'
613 && ! strcmp (tname, "longjmp"))
614 flags |= ECF_NORETURN;
617 return flags;
620 /* Similar to special_function_p; return a set of ERF_ flags for the
621 function FNDECL. */
622 static int
623 decl_return_flags (tree fndecl)
625 tree attr;
626 tree type = TREE_TYPE (fndecl);
627 if (!type)
628 return 0;
630 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
631 if (!attr)
632 return 0;
634 attr = TREE_VALUE (TREE_VALUE (attr));
635 if (!attr || TREE_STRING_LENGTH (attr) < 1)
636 return 0;
638 switch (TREE_STRING_POINTER (attr)[0])
640 case '1':
641 case '2':
642 case '3':
643 case '4':
644 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
646 case 'm':
647 return ERF_NOALIAS;
649 case '.':
650 default:
651 return 0;
655 /* Return nonzero when FNDECL represents a call to setjmp. */
658 setjmp_call_p (const_tree fndecl)
660 if (DECL_IS_RETURNS_TWICE (fndecl))
661 return ECF_RETURNS_TWICE;
662 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
666 /* Return true if STMT is an alloca call. */
668 bool
669 gimple_alloca_call_p (const_gimple stmt)
671 tree fndecl;
673 if (!is_gimple_call (stmt))
674 return false;
676 fndecl = gimple_call_fndecl (stmt);
677 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
678 return true;
680 return false;
683 /* Return true when exp contains alloca call. */
685 bool
686 alloca_call_p (const_tree exp)
688 tree fndecl;
689 if (TREE_CODE (exp) == CALL_EXPR
690 && (fndecl = get_callee_fndecl (exp))
691 && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
692 return true;
693 return false;
696 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
697 function. Return FALSE otherwise. */
699 static bool
700 is_tm_builtin (const_tree fndecl)
702 if (fndecl == NULL)
703 return false;
705 if (decl_is_tm_clone (fndecl))
706 return true;
708 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
710 switch (DECL_FUNCTION_CODE (fndecl))
712 case BUILT_IN_TM_COMMIT:
713 case BUILT_IN_TM_COMMIT_EH:
714 case BUILT_IN_TM_ABORT:
715 case BUILT_IN_TM_IRREVOCABLE:
716 case BUILT_IN_TM_GETTMCLONE_IRR:
717 case BUILT_IN_TM_MEMCPY:
718 case BUILT_IN_TM_MEMMOVE:
719 case BUILT_IN_TM_MEMSET:
720 CASE_BUILT_IN_TM_STORE (1):
721 CASE_BUILT_IN_TM_STORE (2):
722 CASE_BUILT_IN_TM_STORE (4):
723 CASE_BUILT_IN_TM_STORE (8):
724 CASE_BUILT_IN_TM_STORE (FLOAT):
725 CASE_BUILT_IN_TM_STORE (DOUBLE):
726 CASE_BUILT_IN_TM_STORE (LDOUBLE):
727 CASE_BUILT_IN_TM_STORE (M64):
728 CASE_BUILT_IN_TM_STORE (M128):
729 CASE_BUILT_IN_TM_STORE (M256):
730 CASE_BUILT_IN_TM_LOAD (1):
731 CASE_BUILT_IN_TM_LOAD (2):
732 CASE_BUILT_IN_TM_LOAD (4):
733 CASE_BUILT_IN_TM_LOAD (8):
734 CASE_BUILT_IN_TM_LOAD (FLOAT):
735 CASE_BUILT_IN_TM_LOAD (DOUBLE):
736 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
737 CASE_BUILT_IN_TM_LOAD (M64):
738 CASE_BUILT_IN_TM_LOAD (M128):
739 CASE_BUILT_IN_TM_LOAD (M256):
740 case BUILT_IN_TM_LOG:
741 case BUILT_IN_TM_LOG_1:
742 case BUILT_IN_TM_LOG_2:
743 case BUILT_IN_TM_LOG_4:
744 case BUILT_IN_TM_LOG_8:
745 case BUILT_IN_TM_LOG_FLOAT:
746 case BUILT_IN_TM_LOG_DOUBLE:
747 case BUILT_IN_TM_LOG_LDOUBLE:
748 case BUILT_IN_TM_LOG_M64:
749 case BUILT_IN_TM_LOG_M128:
750 case BUILT_IN_TM_LOG_M256:
751 return true;
752 default:
753 break;
756 return false;
759 /* Detect flags (function attributes) from the function decl or type node. */
762 flags_from_decl_or_type (const_tree exp)
764 int flags = 0;
766 if (DECL_P (exp))
768 /* The function exp may have the `malloc' attribute. */
769 if (DECL_IS_MALLOC (exp))
770 flags |= ECF_MALLOC;
772 /* The function exp may have the `returns_twice' attribute. */
773 if (DECL_IS_RETURNS_TWICE (exp))
774 flags |= ECF_RETURNS_TWICE;
776 /* Process the pure and const attributes. */
777 if (TREE_READONLY (exp))
778 flags |= ECF_CONST;
779 if (DECL_PURE_P (exp))
780 flags |= ECF_PURE;
781 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
782 flags |= ECF_LOOPING_CONST_OR_PURE;
784 if (DECL_IS_NOVOPS (exp))
785 flags |= ECF_NOVOPS;
786 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
787 flags |= ECF_LEAF;
789 if (TREE_NOTHROW (exp))
790 flags |= ECF_NOTHROW;
792 if (flag_tm)
794 if (is_tm_builtin (exp))
795 flags |= ECF_TM_BUILTIN;
796 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
797 || lookup_attribute ("transaction_pure",
798 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
799 flags |= ECF_TM_PURE;
802 flags = special_function_p (exp, flags);
804 else if (TYPE_P (exp))
806 if (TYPE_READONLY (exp))
807 flags |= ECF_CONST;
809 if (flag_tm
810 && ((flags & ECF_CONST) != 0
811 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
812 flags |= ECF_TM_PURE;
814 else
815 gcc_unreachable ();
817 if (TREE_THIS_VOLATILE (exp))
819 flags |= ECF_NORETURN;
820 if (flags & (ECF_CONST|ECF_PURE))
821 flags |= ECF_LOOPING_CONST_OR_PURE;
824 return flags;
827 /* Detect flags from a CALL_EXPR. */
830 call_expr_flags (const_tree t)
832 int flags;
833 tree decl = get_callee_fndecl (t);
835 if (decl)
836 flags = flags_from_decl_or_type (decl);
837 else if (CALL_EXPR_FN (t) == NULL_TREE)
838 flags = internal_fn_flags (CALL_EXPR_IFN (t));
839 else
841 t = TREE_TYPE (CALL_EXPR_FN (t));
842 if (t && TREE_CODE (t) == POINTER_TYPE)
843 flags = flags_from_decl_or_type (TREE_TYPE (t));
844 else
845 flags = 0;
848 return flags;
851 /* Return true if TYPE should be passed by invisible reference. */
853 bool
854 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
855 tree type, bool named_arg)
857 if (type)
859 /* If this type contains non-trivial constructors, then it is
860 forbidden for the middle-end to create any new copies. */
861 if (TREE_ADDRESSABLE (type))
862 return true;
864 /* GCC post 3.4 passes *all* variable sized types by reference. */
865 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
866 return true;
868 /* If a record type should be passed the same as its first (and only)
869 member, use the type and mode of that member. */
870 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
872 type = TREE_TYPE (first_field (type));
873 mode = TYPE_MODE (type);
877 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
878 type, named_arg);
881 /* Return true if TYPE, which is passed by reference, should be callee
882 copied instead of caller copied. */
884 bool
885 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
886 tree type, bool named_arg)
888 if (type && TREE_ADDRESSABLE (type))
889 return false;
890 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
891 named_arg);
895 /* Precompute all register parameters as described by ARGS, storing values
896 into fields within the ARGS array.
898 NUM_ACTUALS indicates the total number elements in the ARGS array.
900 Set REG_PARM_SEEN if we encounter a register parameter. */
902 static void
903 precompute_register_parameters (int num_actuals, struct arg_data *args,
904 int *reg_parm_seen)
906 int i;
908 *reg_parm_seen = 0;
910 for (i = 0; i < num_actuals; i++)
911 if (args[i].reg != 0 && ! args[i].pass_on_stack)
913 *reg_parm_seen = 1;
915 if (args[i].value == 0)
917 push_temp_slots ();
918 args[i].value = expand_normal (args[i].tree_value);
919 preserve_temp_slots (args[i].value);
920 pop_temp_slots ();
923 /* If we are to promote the function arg to a wider mode,
924 do it now. */
926 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
927 args[i].value
928 = convert_modes (args[i].mode,
929 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
930 args[i].value, args[i].unsignedp);
932 /* If the value is a non-legitimate constant, force it into a
933 pseudo now. TLS symbols sometimes need a call to resolve. */
934 if (CONSTANT_P (args[i].value)
935 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
936 args[i].value = force_reg (args[i].mode, args[i].value);
938 /* If we're going to have to load the value by parts, pull the
939 parts into pseudos. The part extraction process can involve
940 non-trivial computation. */
941 if (GET_CODE (args[i].reg) == PARALLEL)
943 tree type = TREE_TYPE (args[i].tree_value);
944 args[i].parallel_value
945 = emit_group_load_into_temps (args[i].reg, args[i].value,
946 type, int_size_in_bytes (type));
949 /* If the value is expensive, and we are inside an appropriately
950 short loop, put the value into a pseudo and then put the pseudo
951 into the hard reg.
953 For small register classes, also do this if this call uses
954 register parameters. This is to avoid reload conflicts while
955 loading the parameters registers. */
957 else if ((! (REG_P (args[i].value)
958 || (GET_CODE (args[i].value) == SUBREG
959 && REG_P (SUBREG_REG (args[i].value)))))
960 && args[i].mode != BLKmode
961 && (set_src_cost (args[i].value, args[i].mode,
962 optimize_insn_for_speed_p ())
963 > COSTS_N_INSNS (1))
964 && ((*reg_parm_seen
965 && targetm.small_register_classes_for_mode_p (args[i].mode))
966 || optimize))
967 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
971 #ifdef REG_PARM_STACK_SPACE
973 /* The argument list is the property of the called routine and it
974 may clobber it. If the fixed area has been used for previous
975 parameters, we must save and restore it. */
977 static rtx
978 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
980 int low;
981 int high;
983 /* Compute the boundary of the area that needs to be saved, if any. */
984 high = reg_parm_stack_space;
985 if (ARGS_GROW_DOWNWARD)
986 high += 1;
988 if (high > highest_outgoing_arg_in_use)
989 high = highest_outgoing_arg_in_use;
991 for (low = 0; low < high; low++)
992 if (stack_usage_map[low] != 0)
994 int num_to_save;
995 machine_mode save_mode;
996 int delta;
997 rtx addr;
998 rtx stack_area;
999 rtx save_area;
1001 while (stack_usage_map[--high] == 0)
1004 *low_to_save = low;
1005 *high_to_save = high;
1007 num_to_save = high - low + 1;
1008 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1010 /* If we don't have the required alignment, must do this
1011 in BLKmode. */
1012 if ((low & (MIN (GET_MODE_SIZE (save_mode),
1013 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1014 save_mode = BLKmode;
1016 if (ARGS_GROW_DOWNWARD)
1017 delta = -high;
1018 else
1019 delta = low;
1021 addr = plus_constant (Pmode, argblock, delta);
1022 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1024 set_mem_align (stack_area, PARM_BOUNDARY);
1025 if (save_mode == BLKmode)
1027 save_area = assign_stack_temp (BLKmode, num_to_save);
1028 emit_block_move (validize_mem (save_area), stack_area,
1029 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1031 else
1033 save_area = gen_reg_rtx (save_mode);
1034 emit_move_insn (save_area, stack_area);
1037 return save_area;
1040 return NULL_RTX;
1043 static void
1044 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1046 machine_mode save_mode = GET_MODE (save_area);
1047 int delta;
1048 rtx addr, stack_area;
1050 if (ARGS_GROW_DOWNWARD)
1051 delta = -high_to_save;
1052 else
1053 delta = low_to_save;
1055 addr = plus_constant (Pmode, argblock, delta);
1056 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1057 set_mem_align (stack_area, PARM_BOUNDARY);
1059 if (save_mode != BLKmode)
1060 emit_move_insn (stack_area, save_area);
1061 else
1062 emit_block_move (stack_area, validize_mem (save_area),
1063 GEN_INT (high_to_save - low_to_save + 1),
1064 BLOCK_OP_CALL_PARM);
1066 #endif /* REG_PARM_STACK_SPACE */
1068 /* If any elements in ARGS refer to parameters that are to be passed in
1069 registers, but not in memory, and whose alignment does not permit a
1070 direct copy into registers. Copy the values into a group of pseudos
1071 which we will later copy into the appropriate hard registers.
1073 Pseudos for each unaligned argument will be stored into the array
1074 args[argnum].aligned_regs. The caller is responsible for deallocating
1075 the aligned_regs array if it is nonzero. */
1077 static void
1078 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1080 int i, j;
1082 for (i = 0; i < num_actuals; i++)
1083 if (args[i].reg != 0 && ! args[i].pass_on_stack
1084 && GET_CODE (args[i].reg) != PARALLEL
1085 && args[i].mode == BLKmode
1086 && MEM_P (args[i].value)
1087 && (MEM_ALIGN (args[i].value)
1088 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1090 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1091 int endian_correction = 0;
1093 if (args[i].partial)
1095 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1096 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1098 else
1100 args[i].n_aligned_regs
1101 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1104 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1106 /* Structures smaller than a word are normally aligned to the
1107 least significant byte. On a BYTES_BIG_ENDIAN machine,
1108 this means we must skip the empty high order bytes when
1109 calculating the bit offset. */
1110 if (bytes < UNITS_PER_WORD
1111 #ifdef BLOCK_REG_PADDING
1112 && (BLOCK_REG_PADDING (args[i].mode,
1113 TREE_TYPE (args[i].tree_value), 1)
1114 == downward)
1115 #else
1116 && BYTES_BIG_ENDIAN
1117 #endif
1119 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1121 for (j = 0; j < args[i].n_aligned_regs; j++)
1123 rtx reg = gen_reg_rtx (word_mode);
1124 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1125 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1127 args[i].aligned_regs[j] = reg;
1128 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1129 word_mode, word_mode);
1131 /* There is no need to restrict this code to loading items
1132 in TYPE_ALIGN sized hunks. The bitfield instructions can
1133 load up entire word sized registers efficiently.
1135 ??? This may not be needed anymore.
1136 We use to emit a clobber here but that doesn't let later
1137 passes optimize the instructions we emit. By storing 0 into
1138 the register later passes know the first AND to zero out the
1139 bitfield being set in the register is unnecessary. The store
1140 of 0 will be deleted as will at least the first AND. */
1142 emit_move_insn (reg, const0_rtx);
1144 bytes -= bitsize / BITS_PER_UNIT;
1145 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1146 word_mode, word);
1151 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1152 CALL_EXPR EXP.
1154 NUM_ACTUALS is the total number of parameters.
1156 N_NAMED_ARGS is the total number of named arguments.
1158 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1159 value, or null.
1161 FNDECL is the tree code for the target of this call (if known)
1163 ARGS_SO_FAR holds state needed by the target to know where to place
1164 the next argument.
1166 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1167 for arguments which are passed in registers.
1169 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1170 and may be modified by this routine.
1172 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1173 flags which may be modified by this routine.
1175 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1176 that requires allocation of stack space.
1178 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1179 the thunked-to function. */
1181 static void
1182 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1183 struct arg_data *args,
1184 struct args_size *args_size,
1185 int n_named_args ATTRIBUTE_UNUSED,
1186 tree exp, tree struct_value_addr_value,
1187 tree fndecl, tree fntype,
1188 cumulative_args_t args_so_far,
1189 int reg_parm_stack_space,
1190 rtx *old_stack_level, int *old_pending_adj,
1191 int *must_preallocate, int *ecf_flags,
1192 bool *may_tailcall, bool call_from_thunk_p)
1194 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1195 location_t loc = EXPR_LOCATION (exp);
1197 /* Count arg position in order args appear. */
1198 int argpos;
1200 int i;
1202 args_size->constant = 0;
1203 args_size->var = 0;
1205 bitmap_obstack_initialize (NULL);
1207 /* In this loop, we consider args in the order they are written.
1208 We fill up ARGS from the back. */
1210 i = num_actuals - 1;
1212 int j = i, ptr_arg = -1;
1213 call_expr_arg_iterator iter;
1214 tree arg;
1215 bitmap slots = NULL;
1217 if (struct_value_addr_value)
1219 args[j].tree_value = struct_value_addr_value;
1220 j--;
1222 /* If we pass structure address then we need to
1223 create bounds for it. Since created bounds is
1224 a call statement, we expand it right here to avoid
1225 fixing all other places where it may be expanded. */
1226 if (CALL_WITH_BOUNDS_P (exp))
1228 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1229 args[j].tree_value
1230 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1231 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1232 EXPAND_NORMAL, 0, false);
1233 args[j].pointer_arg = j + 1;
1234 j--;
1237 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1239 tree argtype = TREE_TYPE (arg);
1241 /* Remember last param with pointer and associate it
1242 with following pointer bounds. */
1243 if (CALL_WITH_BOUNDS_P (exp)
1244 && chkp_type_has_pointer (argtype))
1246 if (slots)
1247 BITMAP_FREE (slots);
1248 ptr_arg = j;
1249 if (!BOUNDED_TYPE_P (argtype))
1251 slots = BITMAP_ALLOC (NULL);
1252 chkp_find_bound_slots (argtype, slots);
1255 else if (POINTER_BOUNDS_TYPE_P (argtype))
1257 /* We expect bounds in instrumented calls only.
1258 Otherwise it is a sign we lost flag due to some optimization
1259 and may emit call args incorrectly. */
1260 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1262 /* For structures look for the next available pointer. */
1263 if (ptr_arg != -1 && slots)
1265 unsigned bnd_no = bitmap_first_set_bit (slots);
1266 args[j].pointer_offset =
1267 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1269 bitmap_clear_bit (slots, bnd_no);
1271 /* Check we have no more pointers in the structure. */
1272 if (bitmap_empty_p (slots))
1273 BITMAP_FREE (slots);
1275 args[j].pointer_arg = ptr_arg;
1277 /* Check we covered all pointers in the previous
1278 non bounds arg. */
1279 if (!slots)
1280 ptr_arg = -1;
1282 else
1283 ptr_arg = -1;
1285 if (targetm.calls.split_complex_arg
1286 && argtype
1287 && TREE_CODE (argtype) == COMPLEX_TYPE
1288 && targetm.calls.split_complex_arg (argtype))
1290 tree subtype = TREE_TYPE (argtype);
1291 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1292 j--;
1293 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1295 else
1296 args[j].tree_value = arg;
1297 j--;
1300 if (slots)
1301 BITMAP_FREE (slots);
1304 bitmap_obstack_release (NULL);
1306 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1307 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1309 tree type = TREE_TYPE (args[i].tree_value);
1310 int unsignedp;
1311 machine_mode mode;
1313 /* Replace erroneous argument with constant zero. */
1314 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1315 args[i].tree_value = integer_zero_node, type = integer_type_node;
1317 /* If TYPE is a transparent union or record, pass things the way
1318 we would pass the first field of the union or record. We have
1319 already verified that the modes are the same. */
1320 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1321 && TYPE_TRANSPARENT_AGGR (type))
1322 type = TREE_TYPE (first_field (type));
1324 /* Decide where to pass this arg.
1326 args[i].reg is nonzero if all or part is passed in registers.
1328 args[i].partial is nonzero if part but not all is passed in registers,
1329 and the exact value says how many bytes are passed in registers.
1331 args[i].pass_on_stack is nonzero if the argument must at least be
1332 computed on the stack. It may then be loaded back into registers
1333 if args[i].reg is nonzero.
1335 These decisions are driven by the FUNCTION_... macros and must agree
1336 with those made by function.c. */
1338 /* See if this argument should be passed by invisible reference. */
1339 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1340 type, argpos < n_named_args))
1342 bool callee_copies;
1343 tree base = NULL_TREE;
1345 callee_copies
1346 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1347 type, argpos < n_named_args);
1349 /* If we're compiling a thunk, pass through invisible references
1350 instead of making a copy. */
1351 if (call_from_thunk_p
1352 || (callee_copies
1353 && !TREE_ADDRESSABLE (type)
1354 && (base = get_base_address (args[i].tree_value))
1355 && TREE_CODE (base) != SSA_NAME
1356 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1358 /* We may have turned the parameter value into an SSA name.
1359 Go back to the original parameter so we can take the
1360 address. */
1361 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1363 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1364 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1365 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1367 /* Argument setup code may have copied the value to register. We
1368 revert that optimization now because the tail call code must
1369 use the original location. */
1370 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1371 && !MEM_P (DECL_RTL (args[i].tree_value))
1372 && DECL_INCOMING_RTL (args[i].tree_value)
1373 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1374 set_decl_rtl (args[i].tree_value,
1375 DECL_INCOMING_RTL (args[i].tree_value));
1377 mark_addressable (args[i].tree_value);
1379 /* We can't use sibcalls if a callee-copied argument is
1380 stored in the current function's frame. */
1381 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1382 *may_tailcall = false;
1384 args[i].tree_value = build_fold_addr_expr_loc (loc,
1385 args[i].tree_value);
1386 type = TREE_TYPE (args[i].tree_value);
1388 if (*ecf_flags & ECF_CONST)
1389 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1391 else
1393 /* We make a copy of the object and pass the address to the
1394 function being called. */
1395 rtx copy;
1397 if (!COMPLETE_TYPE_P (type)
1398 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1399 || (flag_stack_check == GENERIC_STACK_CHECK
1400 && compare_tree_int (TYPE_SIZE_UNIT (type),
1401 STACK_CHECK_MAX_VAR_SIZE) > 0))
1403 /* This is a variable-sized object. Make space on the stack
1404 for it. */
1405 rtx size_rtx = expr_size (args[i].tree_value);
1407 if (*old_stack_level == 0)
1409 emit_stack_save (SAVE_BLOCK, old_stack_level);
1410 *old_pending_adj = pending_stack_adjust;
1411 pending_stack_adjust = 0;
1414 /* We can pass TRUE as the 4th argument because we just
1415 saved the stack pointer and will restore it right after
1416 the call. */
1417 copy = allocate_dynamic_stack_space (size_rtx,
1418 TYPE_ALIGN (type),
1419 TYPE_ALIGN (type),
1420 true);
1421 copy = gen_rtx_MEM (BLKmode, copy);
1422 set_mem_attributes (copy, type, 1);
1424 else
1425 copy = assign_temp (type, 1, 0);
1427 store_expr (args[i].tree_value, copy, 0, false);
1429 /* Just change the const function to pure and then let
1430 the next test clear the pure based on
1431 callee_copies. */
1432 if (*ecf_flags & ECF_CONST)
1434 *ecf_flags &= ~ECF_CONST;
1435 *ecf_flags |= ECF_PURE;
1438 if (!callee_copies && *ecf_flags & ECF_PURE)
1439 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1441 args[i].tree_value
1442 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1443 type = TREE_TYPE (args[i].tree_value);
1444 *may_tailcall = false;
1448 unsignedp = TYPE_UNSIGNED (type);
1449 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1450 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1452 args[i].unsignedp = unsignedp;
1453 args[i].mode = mode;
1455 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1456 argpos < n_named_args);
1458 if (args[i].reg && CONST_INT_P (args[i].reg))
1460 args[i].special_slot = args[i].reg;
1461 args[i].reg = NULL;
1464 /* If this is a sibling call and the machine has register windows, the
1465 register window has to be unwinded before calling the routine, so
1466 arguments have to go into the incoming registers. */
1467 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1468 args[i].tail_call_reg
1469 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1470 argpos < n_named_args);
1471 else
1472 args[i].tail_call_reg = args[i].reg;
1474 if (args[i].reg)
1475 args[i].partial
1476 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1477 argpos < n_named_args);
1479 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1481 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1482 it means that we are to pass this arg in the register(s) designated
1483 by the PARALLEL, but also to pass it in the stack. */
1484 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1485 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1486 args[i].pass_on_stack = 1;
1488 /* If this is an addressable type, we must preallocate the stack
1489 since we must evaluate the object into its final location.
1491 If this is to be passed in both registers and the stack, it is simpler
1492 to preallocate. */
1493 if (TREE_ADDRESSABLE (type)
1494 || (args[i].pass_on_stack && args[i].reg != 0))
1495 *must_preallocate = 1;
1497 /* No stack allocation and padding for bounds. */
1498 if (POINTER_BOUNDS_P (args[i].tree_value))
1500 /* Compute the stack-size of this argument. */
1501 else if (args[i].reg == 0 || args[i].partial != 0
1502 || reg_parm_stack_space > 0
1503 || args[i].pass_on_stack)
1504 locate_and_pad_parm (mode, type,
1505 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1507 #else
1508 args[i].reg != 0,
1509 #endif
1510 reg_parm_stack_space,
1511 args[i].pass_on_stack ? 0 : args[i].partial,
1512 fndecl, args_size, &args[i].locate);
1513 #ifdef BLOCK_REG_PADDING
1514 else
1515 /* The argument is passed entirely in registers. See at which
1516 end it should be padded. */
1517 args[i].locate.where_pad =
1518 BLOCK_REG_PADDING (mode, type,
1519 int_size_in_bytes (type) <= UNITS_PER_WORD);
1520 #endif
1522 /* Update ARGS_SIZE, the total stack space for args so far. */
1524 args_size->constant += args[i].locate.size.constant;
1525 if (args[i].locate.size.var)
1526 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1528 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1529 have been used, etc. */
1531 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1532 type, argpos < n_named_args);
1536 /* Update ARGS_SIZE to contain the total size for the argument block.
1537 Return the original constant component of the argument block's size.
1539 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1540 for arguments passed in registers. */
1542 static int
1543 compute_argument_block_size (int reg_parm_stack_space,
1544 struct args_size *args_size,
1545 tree fndecl ATTRIBUTE_UNUSED,
1546 tree fntype ATTRIBUTE_UNUSED,
1547 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1549 int unadjusted_args_size = args_size->constant;
1551 /* For accumulate outgoing args mode we don't need to align, since the frame
1552 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1553 backends from generating misaligned frame sizes. */
1554 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1555 preferred_stack_boundary = STACK_BOUNDARY;
1557 /* Compute the actual size of the argument block required. The variable
1558 and constant sizes must be combined, the size may have to be rounded,
1559 and there may be a minimum required size. */
1561 if (args_size->var)
1563 args_size->var = ARGS_SIZE_TREE (*args_size);
1564 args_size->constant = 0;
1566 preferred_stack_boundary /= BITS_PER_UNIT;
1567 if (preferred_stack_boundary > 1)
1569 /* We don't handle this case yet. To handle it correctly we have
1570 to add the delta, round and subtract the delta.
1571 Currently no machine description requires this support. */
1572 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1573 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1576 if (reg_parm_stack_space > 0)
1578 args_size->var
1579 = size_binop (MAX_EXPR, args_size->var,
1580 ssize_int (reg_parm_stack_space));
1582 /* The area corresponding to register parameters is not to count in
1583 the size of the block we need. So make the adjustment. */
1584 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1585 args_size->var
1586 = size_binop (MINUS_EXPR, args_size->var,
1587 ssize_int (reg_parm_stack_space));
1590 else
1592 preferred_stack_boundary /= BITS_PER_UNIT;
1593 if (preferred_stack_boundary < 1)
1594 preferred_stack_boundary = 1;
1595 args_size->constant = (((args_size->constant
1596 + stack_pointer_delta
1597 + preferred_stack_boundary - 1)
1598 / preferred_stack_boundary
1599 * preferred_stack_boundary)
1600 - stack_pointer_delta);
1602 args_size->constant = MAX (args_size->constant,
1603 reg_parm_stack_space);
1605 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1606 args_size->constant -= reg_parm_stack_space;
1608 return unadjusted_args_size;
1611 /* Precompute parameters as needed for a function call.
1613 FLAGS is mask of ECF_* constants.
1615 NUM_ACTUALS is the number of arguments.
1617 ARGS is an array containing information for each argument; this
1618 routine fills in the INITIAL_VALUE and VALUE fields for each
1619 precomputed argument. */
1621 static void
1622 precompute_arguments (int num_actuals, struct arg_data *args)
1624 int i;
1626 /* If this is a libcall, then precompute all arguments so that we do not
1627 get extraneous instructions emitted as part of the libcall sequence. */
1629 /* If we preallocated the stack space, and some arguments must be passed
1630 on the stack, then we must precompute any parameter which contains a
1631 function call which will store arguments on the stack.
1632 Otherwise, evaluating the parameter may clobber previous parameters
1633 which have already been stored into the stack. (we have code to avoid
1634 such case by saving the outgoing stack arguments, but it results in
1635 worse code) */
1636 if (!ACCUMULATE_OUTGOING_ARGS)
1637 return;
1639 for (i = 0; i < num_actuals; i++)
1641 tree type;
1642 machine_mode mode;
1644 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1645 continue;
1647 /* If this is an addressable type, we cannot pre-evaluate it. */
1648 type = TREE_TYPE (args[i].tree_value);
1649 gcc_assert (!TREE_ADDRESSABLE (type));
1651 args[i].initial_value = args[i].value
1652 = expand_normal (args[i].tree_value);
1654 mode = TYPE_MODE (type);
1655 if (mode != args[i].mode)
1657 int unsignedp = args[i].unsignedp;
1658 args[i].value
1659 = convert_modes (args[i].mode, mode,
1660 args[i].value, args[i].unsignedp);
1662 /* CSE will replace this only if it contains args[i].value
1663 pseudo, so convert it down to the declared mode using
1664 a SUBREG. */
1665 if (REG_P (args[i].value)
1666 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1667 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1669 args[i].initial_value
1670 = gen_lowpart_SUBREG (mode, args[i].value);
1671 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1672 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
1678 /* Given the current state of MUST_PREALLOCATE and information about
1679 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1680 compute and return the final value for MUST_PREALLOCATE. */
1682 static int
1683 finalize_must_preallocate (int must_preallocate, int num_actuals,
1684 struct arg_data *args, struct args_size *args_size)
1686 /* See if we have or want to preallocate stack space.
1688 If we would have to push a partially-in-regs parm
1689 before other stack parms, preallocate stack space instead.
1691 If the size of some parm is not a multiple of the required stack
1692 alignment, we must preallocate.
1694 If the total size of arguments that would otherwise create a copy in
1695 a temporary (such as a CALL) is more than half the total argument list
1696 size, preallocation is faster.
1698 Another reason to preallocate is if we have a machine (like the m88k)
1699 where stack alignment is required to be maintained between every
1700 pair of insns, not just when the call is made. However, we assume here
1701 that such machines either do not have push insns (and hence preallocation
1702 would occur anyway) or the problem is taken care of with
1703 PUSH_ROUNDING. */
1705 if (! must_preallocate)
1707 int partial_seen = 0;
1708 int copy_to_evaluate_size = 0;
1709 int i;
1711 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1713 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1714 partial_seen = 1;
1715 else if (partial_seen && args[i].reg == 0)
1716 must_preallocate = 1;
1717 /* We preallocate in case there are bounds passed
1718 in the bounds table to have precomputed address
1719 for bounds association. */
1720 else if (POINTER_BOUNDS_P (args[i].tree_value)
1721 && !args[i].reg)
1722 must_preallocate = 1;
1724 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1725 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1726 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1727 || TREE_CODE (args[i].tree_value) == COND_EXPR
1728 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1729 copy_to_evaluate_size
1730 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1733 if (copy_to_evaluate_size * 2 >= args_size->constant
1734 && args_size->constant > 0)
1735 must_preallocate = 1;
1737 return must_preallocate;
1740 /* If we preallocated stack space, compute the address of each argument
1741 and store it into the ARGS array.
1743 We need not ensure it is a valid memory address here; it will be
1744 validized when it is used.
1746 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1748 static void
1749 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1751 if (argblock)
1753 rtx arg_reg = argblock;
1754 int i, arg_offset = 0;
1756 if (GET_CODE (argblock) == PLUS)
1757 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1759 for (i = 0; i < num_actuals; i++)
1761 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1762 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1763 rtx addr;
1764 unsigned int align, boundary;
1765 unsigned int units_on_stack = 0;
1766 machine_mode partial_mode = VOIDmode;
1768 /* Skip this parm if it will not be passed on the stack. */
1769 if (! args[i].pass_on_stack
1770 && args[i].reg != 0
1771 && args[i].partial == 0)
1772 continue;
1774 /* Pointer Bounds are never passed on the stack. */
1775 if (POINTER_BOUNDS_P (args[i].tree_value))
1776 continue;
1778 if (CONST_INT_P (offset))
1779 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
1780 else
1781 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1783 addr = plus_constant (Pmode, addr, arg_offset);
1785 if (args[i].partial != 0)
1787 /* Only part of the parameter is being passed on the stack.
1788 Generate a simple memory reference of the correct size. */
1789 units_on_stack = args[i].locate.size.constant;
1790 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1791 MODE_INT, 1);
1792 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1793 set_mem_size (args[i].stack, units_on_stack);
1795 else
1797 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1798 set_mem_attributes (args[i].stack,
1799 TREE_TYPE (args[i].tree_value), 1);
1801 align = BITS_PER_UNIT;
1802 boundary = args[i].locate.boundary;
1803 if (args[i].locate.where_pad != downward)
1804 align = boundary;
1805 else if (CONST_INT_P (offset))
1807 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1808 align = align & -align;
1810 set_mem_align (args[i].stack, align);
1812 if (CONST_INT_P (slot_offset))
1813 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
1814 else
1815 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1817 addr = plus_constant (Pmode, addr, arg_offset);
1819 if (args[i].partial != 0)
1821 /* Only part of the parameter is being passed on the stack.
1822 Generate a simple memory reference of the correct size.
1824 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1825 set_mem_size (args[i].stack_slot, units_on_stack);
1827 else
1829 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1830 set_mem_attributes (args[i].stack_slot,
1831 TREE_TYPE (args[i].tree_value), 1);
1833 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1835 /* Function incoming arguments may overlap with sibling call
1836 outgoing arguments and we cannot allow reordering of reads
1837 from function arguments with stores to outgoing arguments
1838 of sibling calls. */
1839 set_mem_alias_set (args[i].stack, 0);
1840 set_mem_alias_set (args[i].stack_slot, 0);
1845 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1846 in a call instruction.
1848 FNDECL is the tree node for the target function. For an indirect call
1849 FNDECL will be NULL_TREE.
1851 ADDR is the operand 0 of CALL_EXPR for this call. */
1853 static rtx
1854 rtx_for_function_call (tree fndecl, tree addr)
1856 rtx funexp;
1858 /* Get the function to call, in the form of RTL. */
1859 if (fndecl)
1861 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1862 TREE_USED (fndecl) = 1;
1864 /* Get a SYMBOL_REF rtx for the function address. */
1865 funexp = XEXP (DECL_RTL (fndecl), 0);
1867 else
1868 /* Generate an rtx (probably a pseudo-register) for the address. */
1870 push_temp_slots ();
1871 funexp = expand_normal (addr);
1872 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1874 return funexp;
1877 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1878 static struct
1880 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1881 or NULL_RTX if none has been scanned yet. */
1882 rtx_insn *scan_start;
1883 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1884 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1885 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1886 with fixed offset, or PC if this is with variable or unknown offset. */
1887 vec<rtx> cache;
1888 } internal_arg_pointer_exp_state;
1890 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
1892 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1893 the tail call sequence, starting with first insn that hasn't been
1894 scanned yet, and note for each pseudo on the LHS whether it is based
1895 on crtl->args.internal_arg_pointer or not, and what offset from that
1896 that pointer it has. */
1898 static void
1899 internal_arg_pointer_based_exp_scan (void)
1901 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
1903 if (scan_start == NULL_RTX)
1904 insn = get_insns ();
1905 else
1906 insn = NEXT_INSN (scan_start);
1908 while (insn)
1910 rtx set = single_set (insn);
1911 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1913 rtx val = NULL_RTX;
1914 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1915 /* Punt on pseudos set multiple times. */
1916 if (idx < internal_arg_pointer_exp_state.cache.length ()
1917 && (internal_arg_pointer_exp_state.cache[idx]
1918 != NULL_RTX))
1919 val = pc_rtx;
1920 else
1921 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1922 if (val != NULL_RTX)
1924 if (idx >= internal_arg_pointer_exp_state.cache.length ())
1925 internal_arg_pointer_exp_state.cache
1926 .safe_grow_cleared (idx + 1);
1927 internal_arg_pointer_exp_state.cache[idx] = val;
1930 if (NEXT_INSN (insn) == NULL_RTX)
1931 scan_start = insn;
1932 insn = NEXT_INSN (insn);
1935 internal_arg_pointer_exp_state.scan_start = scan_start;
1938 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1939 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1940 it with fixed offset, or PC if this is with variable or unknown offset.
1941 TOPLEVEL is true if the function is invoked at the topmost level. */
1943 static rtx
1944 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
1946 if (CONSTANT_P (rtl))
1947 return NULL_RTX;
1949 if (rtl == crtl->args.internal_arg_pointer)
1950 return const0_rtx;
1952 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1953 return NULL_RTX;
1955 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1957 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1958 if (val == NULL_RTX || val == pc_rtx)
1959 return val;
1960 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
1963 /* When called at the topmost level, scan pseudo assignments in between the
1964 last scanned instruction in the tail call sequence and the latest insn
1965 in that sequence. */
1966 if (toplevel)
1967 internal_arg_pointer_based_exp_scan ();
1969 if (REG_P (rtl))
1971 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1972 if (idx < internal_arg_pointer_exp_state.cache.length ())
1973 return internal_arg_pointer_exp_state.cache[idx];
1975 return NULL_RTX;
1978 subrtx_iterator::array_type array;
1979 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
1981 const_rtx x = *iter;
1982 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
1983 return pc_rtx;
1984 if (MEM_P (x))
1985 iter.skip_subrtxes ();
1988 return NULL_RTX;
1991 /* Return true if and only if SIZE storage units (usually bytes)
1992 starting from address ADDR overlap with already clobbered argument
1993 area. This function is used to determine if we should give up a
1994 sibcall. */
1996 static bool
1997 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1999 HOST_WIDE_INT i;
2000 rtx val;
2002 if (bitmap_empty_p (stored_args_map))
2003 return false;
2004 val = internal_arg_pointer_based_exp (addr, true);
2005 if (val == NULL_RTX)
2006 return false;
2007 else if (val == pc_rtx)
2008 return true;
2009 else
2010 i = INTVAL (val);
2012 if (STACK_GROWS_DOWNWARD)
2013 i -= crtl->args.pretend_args_size;
2014 else
2015 i += crtl->args.pretend_args_size;
2018 if (ARGS_GROW_DOWNWARD)
2019 i = -i - size;
2021 if (size > 0)
2023 unsigned HOST_WIDE_INT k;
2025 for (k = 0; k < size; k++)
2026 if (i + k < SBITMAP_SIZE (stored_args_map)
2027 && bitmap_bit_p (stored_args_map, i + k))
2028 return true;
2031 return false;
2034 /* Do the register loads required for any wholly-register parms or any
2035 parms which are passed both on the stack and in a register. Their
2036 expressions were already evaluated.
2038 Mark all register-parms as living through the call, putting these USE
2039 insns in the CALL_INSN_FUNCTION_USAGE field.
2041 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2042 checking, setting *SIBCALL_FAILURE if appropriate. */
2044 static void
2045 load_register_parameters (struct arg_data *args, int num_actuals,
2046 rtx *call_fusage, int flags, int is_sibcall,
2047 int *sibcall_failure)
2049 int i, j;
2051 for (i = 0; i < num_actuals; i++)
2053 rtx reg = ((flags & ECF_SIBCALL)
2054 ? args[i].tail_call_reg : args[i].reg);
2055 if (reg)
2057 int partial = args[i].partial;
2058 int nregs;
2059 int size = 0;
2060 rtx_insn *before_arg = get_last_insn ();
2061 /* Set non-negative if we must move a word at a time, even if
2062 just one word (e.g, partial == 4 && mode == DFmode). Set
2063 to -1 if we just use a normal move insn. This value can be
2064 zero if the argument is a zero size structure. */
2065 nregs = -1;
2066 if (GET_CODE (reg) == PARALLEL)
2068 else if (partial)
2070 gcc_assert (partial % UNITS_PER_WORD == 0);
2071 nregs = partial / UNITS_PER_WORD;
2073 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2075 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2076 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2078 else
2079 size = GET_MODE_SIZE (args[i].mode);
2081 /* Handle calls that pass values in multiple non-contiguous
2082 locations. The Irix 6 ABI has examples of this. */
2084 if (GET_CODE (reg) == PARALLEL)
2085 emit_group_move (reg, args[i].parallel_value);
2087 /* If simple case, just do move. If normal partial, store_one_arg
2088 has already loaded the register for us. In all other cases,
2089 load the register(s) from memory. */
2091 else if (nregs == -1)
2093 emit_move_insn (reg, args[i].value);
2094 #ifdef BLOCK_REG_PADDING
2095 /* Handle case where we have a value that needs shifting
2096 up to the msb. eg. a QImode value and we're padding
2097 upward on a BYTES_BIG_ENDIAN machine. */
2098 if (size < UNITS_PER_WORD
2099 && (args[i].locate.where_pad
2100 == (BYTES_BIG_ENDIAN ? upward : downward)))
2102 rtx x;
2103 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2105 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2106 report the whole reg as used. Strictly speaking, the
2107 call only uses SIZE bytes at the msb end, but it doesn't
2108 seem worth generating rtl to say that. */
2109 reg = gen_rtx_REG (word_mode, REGNO (reg));
2110 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2111 if (x != reg)
2112 emit_move_insn (reg, x);
2114 #endif
2117 /* If we have pre-computed the values to put in the registers in
2118 the case of non-aligned structures, copy them in now. */
2120 else if (args[i].n_aligned_regs != 0)
2121 for (j = 0; j < args[i].n_aligned_regs; j++)
2122 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2123 args[i].aligned_regs[j]);
2125 else if (partial == 0 || args[i].pass_on_stack)
2127 rtx mem = validize_mem (copy_rtx (args[i].value));
2129 /* Check for overlap with already clobbered argument area,
2130 providing that this has non-zero size. */
2131 if (is_sibcall
2132 && (size == 0
2133 || mem_overlaps_already_clobbered_arg_p
2134 (XEXP (args[i].value, 0), size)))
2135 *sibcall_failure = 1;
2137 if (size % UNITS_PER_WORD == 0
2138 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2139 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2140 else
2142 if (nregs > 1)
2143 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2144 args[i].mode);
2145 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2146 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2147 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2148 rtx x = extract_bit_field (mem, bitsize, bitoff, 1,
2149 dest, word_mode, word_mode);
2150 if (BYTES_BIG_ENDIAN)
2151 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2152 BITS_PER_WORD - bitsize, dest, 1);
2153 if (x != dest)
2154 emit_move_insn (dest, x);
2157 /* Handle a BLKmode that needs shifting. */
2158 if (nregs == 1 && size < UNITS_PER_WORD
2159 #ifdef BLOCK_REG_PADDING
2160 && args[i].locate.where_pad == downward
2161 #else
2162 && BYTES_BIG_ENDIAN
2163 #endif
2166 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2167 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2168 enum tree_code dir = (BYTES_BIG_ENDIAN
2169 ? RSHIFT_EXPR : LSHIFT_EXPR);
2170 rtx x;
2172 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2173 if (x != dest)
2174 emit_move_insn (dest, x);
2178 /* When a parameter is a block, and perhaps in other cases, it is
2179 possible that it did a load from an argument slot that was
2180 already clobbered. */
2181 if (is_sibcall
2182 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2183 *sibcall_failure = 1;
2185 /* Handle calls that pass values in multiple non-contiguous
2186 locations. The Irix 6 ABI has examples of this. */
2187 if (GET_CODE (reg) == PARALLEL)
2188 use_group_regs (call_fusage, reg);
2189 else if (nregs == -1)
2190 use_reg_mode (call_fusage, reg,
2191 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2192 else if (nregs > 0)
2193 use_regs (call_fusage, REGNO (reg), nregs);
2198 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2199 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2200 bytes, then we would need to push some additional bytes to pad the
2201 arguments. So, we compute an adjust to the stack pointer for an
2202 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2203 bytes. Then, when the arguments are pushed the stack will be perfectly
2204 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2205 be popped after the call. Returns the adjustment. */
2207 static int
2208 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2209 struct args_size *args_size,
2210 unsigned int preferred_unit_stack_boundary)
2212 /* The number of bytes to pop so that the stack will be
2213 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2214 HOST_WIDE_INT adjustment;
2215 /* The alignment of the stack after the arguments are pushed, if we
2216 just pushed the arguments without adjust the stack here. */
2217 unsigned HOST_WIDE_INT unadjusted_alignment;
2219 unadjusted_alignment
2220 = ((stack_pointer_delta + unadjusted_args_size)
2221 % preferred_unit_stack_boundary);
2223 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2224 as possible -- leaving just enough left to cancel out the
2225 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2226 PENDING_STACK_ADJUST is non-negative, and congruent to
2227 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2229 /* Begin by trying to pop all the bytes. */
2230 unadjusted_alignment
2231 = (unadjusted_alignment
2232 - (pending_stack_adjust % preferred_unit_stack_boundary));
2233 adjustment = pending_stack_adjust;
2234 /* Push enough additional bytes that the stack will be aligned
2235 after the arguments are pushed. */
2236 if (preferred_unit_stack_boundary > 1)
2238 if (unadjusted_alignment > 0)
2239 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2240 else
2241 adjustment += unadjusted_alignment;
2244 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2245 bytes after the call. The right number is the entire
2246 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2247 by the arguments in the first place. */
2248 args_size->constant
2249 = pending_stack_adjust - adjustment + unadjusted_args_size;
2251 return adjustment;
2254 /* Scan X expression if it does not dereference any argument slots
2255 we already clobbered by tail call arguments (as noted in stored_args_map
2256 bitmap).
2257 Return nonzero if X expression dereferences such argument slots,
2258 zero otherwise. */
2260 static int
2261 check_sibcall_argument_overlap_1 (rtx x)
2263 RTX_CODE code;
2264 int i, j;
2265 const char *fmt;
2267 if (x == NULL_RTX)
2268 return 0;
2270 code = GET_CODE (x);
2272 /* We need not check the operands of the CALL expression itself. */
2273 if (code == CALL)
2274 return 0;
2276 if (code == MEM)
2277 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2278 GET_MODE_SIZE (GET_MODE (x)));
2280 /* Scan all subexpressions. */
2281 fmt = GET_RTX_FORMAT (code);
2282 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2284 if (*fmt == 'e')
2286 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2287 return 1;
2289 else if (*fmt == 'E')
2291 for (j = 0; j < XVECLEN (x, i); j++)
2292 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2293 return 1;
2296 return 0;
2299 /* Scan sequence after INSN if it does not dereference any argument slots
2300 we already clobbered by tail call arguments (as noted in stored_args_map
2301 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2302 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2303 should be 0). Return nonzero if sequence after INSN dereferences such argument
2304 slots, zero otherwise. */
2306 static int
2307 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2308 int mark_stored_args_map)
2310 int low, high;
2312 if (insn == NULL_RTX)
2313 insn = get_insns ();
2314 else
2315 insn = NEXT_INSN (insn);
2317 for (; insn; insn = NEXT_INSN (insn))
2318 if (INSN_P (insn)
2319 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2320 break;
2322 if (mark_stored_args_map)
2324 if (ARGS_GROW_DOWNWARD)
2325 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2326 else
2327 low = arg->locate.slot_offset.constant;
2329 for (high = low + arg->locate.size.constant; low < high; low++)
2330 bitmap_set_bit (stored_args_map, low);
2332 return insn != NULL_RTX;
2335 /* Given that a function returns a value of mode MODE at the most
2336 significant end of hard register VALUE, shift VALUE left or right
2337 as specified by LEFT_P. Return true if some action was needed. */
2339 bool
2340 shift_return_value (machine_mode mode, bool left_p, rtx value)
2342 HOST_WIDE_INT shift;
2344 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2345 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2346 if (shift == 0)
2347 return false;
2349 /* Use ashr rather than lshr for right shifts. This is for the benefit
2350 of the MIPS port, which requires SImode values to be sign-extended
2351 when stored in 64-bit registers. */
2352 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2353 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2354 gcc_unreachable ();
2355 return true;
2358 /* If X is a likely-spilled register value, copy it to a pseudo
2359 register and return that register. Return X otherwise. */
2361 static rtx
2362 avoid_likely_spilled_reg (rtx x)
2364 rtx new_rtx;
2366 if (REG_P (x)
2367 && HARD_REGISTER_P (x)
2368 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2370 /* Make sure that we generate a REG rather than a CONCAT.
2371 Moves into CONCATs can need nontrivial instructions,
2372 and the whole point of this function is to avoid
2373 using the hard register directly in such a situation. */
2374 generating_concat_p = 0;
2375 new_rtx = gen_reg_rtx (GET_MODE (x));
2376 generating_concat_p = 1;
2377 emit_move_insn (new_rtx, x);
2378 return new_rtx;
2380 return x;
2383 /* Generate all the code for a CALL_EXPR exp
2384 and return an rtx for its value.
2385 Store the value in TARGET (specified as an rtx) if convenient.
2386 If the value is stored in TARGET then TARGET is returned.
2387 If IGNORE is nonzero, then we ignore the value of the function call. */
2390 expand_call (tree exp, rtx target, int ignore)
2392 /* Nonzero if we are currently expanding a call. */
2393 static int currently_expanding_call = 0;
2395 /* RTX for the function to be called. */
2396 rtx funexp;
2397 /* Sequence of insns to perform a normal "call". */
2398 rtx_insn *normal_call_insns = NULL;
2399 /* Sequence of insns to perform a tail "call". */
2400 rtx_insn *tail_call_insns = NULL;
2401 /* Data type of the function. */
2402 tree funtype;
2403 tree type_arg_types;
2404 tree rettype;
2405 /* Declaration of the function being called,
2406 or 0 if the function is computed (not known by name). */
2407 tree fndecl = 0;
2408 /* The type of the function being called. */
2409 tree fntype;
2410 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2411 int pass;
2413 /* Register in which non-BLKmode value will be returned,
2414 or 0 if no value or if value is BLKmode. */
2415 rtx valreg;
2416 /* Register(s) in which bounds are returned. */
2417 rtx valbnd = NULL;
2418 /* Address where we should return a BLKmode value;
2419 0 if value not BLKmode. */
2420 rtx structure_value_addr = 0;
2421 /* Nonzero if that address is being passed by treating it as
2422 an extra, implicit first parameter. Otherwise,
2423 it is passed by being copied directly into struct_value_rtx. */
2424 int structure_value_addr_parm = 0;
2425 /* Holds the value of implicit argument for the struct value. */
2426 tree structure_value_addr_value = NULL_TREE;
2427 /* Size of aggregate value wanted, or zero if none wanted
2428 or if we are using the non-reentrant PCC calling convention
2429 or expecting the value in registers. */
2430 HOST_WIDE_INT struct_value_size = 0;
2431 /* Nonzero if called function returns an aggregate in memory PCC style,
2432 by returning the address of where to find it. */
2433 int pcc_struct_value = 0;
2434 rtx struct_value = 0;
2436 /* Number of actual parameters in this call, including struct value addr. */
2437 int num_actuals;
2438 /* Number of named args. Args after this are anonymous ones
2439 and they must all go on the stack. */
2440 int n_named_args;
2441 /* Number of complex actual arguments that need to be split. */
2442 int num_complex_actuals = 0;
2444 /* Vector of information about each argument.
2445 Arguments are numbered in the order they will be pushed,
2446 not the order they are written. */
2447 struct arg_data *args;
2449 /* Total size in bytes of all the stack-parms scanned so far. */
2450 struct args_size args_size;
2451 struct args_size adjusted_args_size;
2452 /* Size of arguments before any adjustments (such as rounding). */
2453 int unadjusted_args_size;
2454 /* Data on reg parms scanned so far. */
2455 CUMULATIVE_ARGS args_so_far_v;
2456 cumulative_args_t args_so_far;
2457 /* Nonzero if a reg parm has been scanned. */
2458 int reg_parm_seen;
2459 /* Nonzero if this is an indirect function call. */
2461 /* Nonzero if we must avoid push-insns in the args for this call.
2462 If stack space is allocated for register parameters, but not by the
2463 caller, then it is preallocated in the fixed part of the stack frame.
2464 So the entire argument block must then be preallocated (i.e., we
2465 ignore PUSH_ROUNDING in that case). */
2467 int must_preallocate = !PUSH_ARGS;
2469 /* Size of the stack reserved for parameter registers. */
2470 int reg_parm_stack_space = 0;
2472 /* Address of space preallocated for stack parms
2473 (on machines that lack push insns), or 0 if space not preallocated. */
2474 rtx argblock = 0;
2476 /* Mask of ECF_ and ERF_ flags. */
2477 int flags = 0;
2478 int return_flags = 0;
2479 #ifdef REG_PARM_STACK_SPACE
2480 /* Define the boundary of the register parm stack space that needs to be
2481 saved, if any. */
2482 int low_to_save, high_to_save;
2483 rtx save_area = 0; /* Place that it is saved */
2484 #endif
2486 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2487 char *initial_stack_usage_map = stack_usage_map;
2488 char *stack_usage_map_buf = NULL;
2490 int old_stack_allocated;
2492 /* State variables to track stack modifications. */
2493 rtx old_stack_level = 0;
2494 int old_stack_arg_under_construction = 0;
2495 int old_pending_adj = 0;
2496 int old_inhibit_defer_pop = inhibit_defer_pop;
2498 /* Some stack pointer alterations we make are performed via
2499 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2500 which we then also need to save/restore along the way. */
2501 int old_stack_pointer_delta = 0;
2503 rtx call_fusage;
2504 tree addr = CALL_EXPR_FN (exp);
2505 int i;
2506 /* The alignment of the stack, in bits. */
2507 unsigned HOST_WIDE_INT preferred_stack_boundary;
2508 /* The alignment of the stack, in bytes. */
2509 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2510 /* The static chain value to use for this call. */
2511 rtx static_chain_value;
2512 /* See if this is "nothrow" function call. */
2513 if (TREE_NOTHROW (exp))
2514 flags |= ECF_NOTHROW;
2516 /* See if we can find a DECL-node for the actual function, and get the
2517 function attributes (flags) from the function decl or type node. */
2518 fndecl = get_callee_fndecl (exp);
2519 if (fndecl)
2521 fntype = TREE_TYPE (fndecl);
2522 flags |= flags_from_decl_or_type (fndecl);
2523 return_flags |= decl_return_flags (fndecl);
2525 else
2527 fntype = TREE_TYPE (TREE_TYPE (addr));
2528 flags |= flags_from_decl_or_type (fntype);
2530 rettype = TREE_TYPE (exp);
2532 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2534 /* Warn if this value is an aggregate type,
2535 regardless of which calling convention we are using for it. */
2536 if (AGGREGATE_TYPE_P (rettype))
2537 warning (OPT_Waggregate_return, "function call has aggregate value");
2539 /* If the result of a non looping pure or const function call is
2540 ignored (or void), and none of its arguments are volatile, we can
2541 avoid expanding the call and just evaluate the arguments for
2542 side-effects. */
2543 if ((flags & (ECF_CONST | ECF_PURE))
2544 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2545 && (ignore || target == const0_rtx
2546 || TYPE_MODE (rettype) == VOIDmode))
2548 bool volatilep = false;
2549 tree arg;
2550 call_expr_arg_iterator iter;
2552 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2553 if (TREE_THIS_VOLATILE (arg))
2555 volatilep = true;
2556 break;
2559 if (! volatilep)
2561 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2562 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2563 return const0_rtx;
2567 #ifdef REG_PARM_STACK_SPACE
2568 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2569 #endif
2571 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2572 && reg_parm_stack_space > 0 && PUSH_ARGS)
2573 must_preallocate = 1;
2575 /* Set up a place to return a structure. */
2577 /* Cater to broken compilers. */
2578 if (aggregate_value_p (exp, fntype))
2580 /* This call returns a big structure. */
2581 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2583 #ifdef PCC_STATIC_STRUCT_RETURN
2585 pcc_struct_value = 1;
2587 #else /* not PCC_STATIC_STRUCT_RETURN */
2589 struct_value_size = int_size_in_bytes (rettype);
2591 /* Even if it is semantically safe to use the target as the return
2592 slot, it may be not sufficiently aligned for the return type. */
2593 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
2594 && target
2595 && MEM_P (target)
2596 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
2597 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
2598 MEM_ALIGN (target))))
2599 structure_value_addr = XEXP (target, 0);
2600 else
2602 /* For variable-sized objects, we must be called with a target
2603 specified. If we were to allocate space on the stack here,
2604 we would have no way of knowing when to free it. */
2605 rtx d = assign_temp (rettype, 1, 1);
2606 structure_value_addr = XEXP (d, 0);
2607 target = 0;
2610 #endif /* not PCC_STATIC_STRUCT_RETURN */
2613 /* Figure out the amount to which the stack should be aligned. */
2614 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2615 if (fndecl)
2617 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
2618 /* Without automatic stack alignment, we can't increase preferred
2619 stack boundary. With automatic stack alignment, it is
2620 unnecessary since unless we can guarantee that all callers will
2621 align the outgoing stack properly, callee has to align its
2622 stack anyway. */
2623 if (i
2624 && i->preferred_incoming_stack_boundary
2625 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2626 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2629 /* Operand 0 is a pointer-to-function; get the type of the function. */
2630 funtype = TREE_TYPE (addr);
2631 gcc_assert (POINTER_TYPE_P (funtype));
2632 funtype = TREE_TYPE (funtype);
2634 /* Count whether there are actual complex arguments that need to be split
2635 into their real and imaginary parts. Munge the type_arg_types
2636 appropriately here as well. */
2637 if (targetm.calls.split_complex_arg)
2639 call_expr_arg_iterator iter;
2640 tree arg;
2641 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2643 tree type = TREE_TYPE (arg);
2644 if (type && TREE_CODE (type) == COMPLEX_TYPE
2645 && targetm.calls.split_complex_arg (type))
2646 num_complex_actuals++;
2648 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2650 else
2651 type_arg_types = TYPE_ARG_TYPES (funtype);
2653 if (flags & ECF_MAY_BE_ALLOCA)
2654 cfun->calls_alloca = 1;
2656 /* If struct_value_rtx is 0, it means pass the address
2657 as if it were an extra parameter. Put the argument expression
2658 in structure_value_addr_value. */
2659 if (structure_value_addr && struct_value == 0)
2661 /* If structure_value_addr is a REG other than
2662 virtual_outgoing_args_rtx, we can use always use it. If it
2663 is not a REG, we must always copy it into a register.
2664 If it is virtual_outgoing_args_rtx, we must copy it to another
2665 register in some cases. */
2666 rtx temp = (!REG_P (structure_value_addr)
2667 || (ACCUMULATE_OUTGOING_ARGS
2668 && stack_arg_under_construction
2669 && structure_value_addr == virtual_outgoing_args_rtx)
2670 ? copy_addr_to_reg (convert_memory_address
2671 (Pmode, structure_value_addr))
2672 : structure_value_addr);
2674 structure_value_addr_value =
2675 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2676 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
2679 /* Count the arguments and set NUM_ACTUALS. */
2680 num_actuals =
2681 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2683 /* Compute number of named args.
2684 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2686 if (type_arg_types != 0)
2687 n_named_args
2688 = (list_length (type_arg_types)
2689 /* Count the struct value address, if it is passed as a parm. */
2690 + structure_value_addr_parm);
2691 else
2692 /* If we know nothing, treat all args as named. */
2693 n_named_args = num_actuals;
2695 /* Start updating where the next arg would go.
2697 On some machines (such as the PA) indirect calls have a different
2698 calling convention than normal calls. The fourth argument in
2699 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2700 or not. */
2701 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2702 args_so_far = pack_cumulative_args (&args_so_far_v);
2704 /* Now possibly adjust the number of named args.
2705 Normally, don't include the last named arg if anonymous args follow.
2706 We do include the last named arg if
2707 targetm.calls.strict_argument_naming() returns nonzero.
2708 (If no anonymous args follow, the result of list_length is actually
2709 one too large. This is harmless.)
2711 If targetm.calls.pretend_outgoing_varargs_named() returns
2712 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2713 this machine will be able to place unnamed args that were passed
2714 in registers into the stack. So treat all args as named. This
2715 allows the insns emitting for a specific argument list to be
2716 independent of the function declaration.
2718 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2719 we do not have any reliable way to pass unnamed args in
2720 registers, so we must force them into memory. */
2722 if (type_arg_types != 0
2723 && targetm.calls.strict_argument_naming (args_so_far))
2725 else if (type_arg_types != 0
2726 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2727 /* Don't include the last named arg. */
2728 --n_named_args;
2729 else
2730 /* Treat all args as named. */
2731 n_named_args = num_actuals;
2733 /* Make a vector to hold all the information about each arg. */
2734 args = XALLOCAVEC (struct arg_data, num_actuals);
2735 memset (args, 0, num_actuals * sizeof (struct arg_data));
2737 /* Build up entries in the ARGS array, compute the size of the
2738 arguments into ARGS_SIZE, etc. */
2739 initialize_argument_information (num_actuals, args, &args_size,
2740 n_named_args, exp,
2741 structure_value_addr_value, fndecl, fntype,
2742 args_so_far, reg_parm_stack_space,
2743 &old_stack_level, &old_pending_adj,
2744 &must_preallocate, &flags,
2745 &try_tail_call, CALL_FROM_THUNK_P (exp));
2747 if (args_size.var)
2748 must_preallocate = 1;
2750 /* Now make final decision about preallocating stack space. */
2751 must_preallocate = finalize_must_preallocate (must_preallocate,
2752 num_actuals, args,
2753 &args_size);
2755 /* If the structure value address will reference the stack pointer, we
2756 must stabilize it. We don't need to do this if we know that we are
2757 not going to adjust the stack pointer in processing this call. */
2759 if (structure_value_addr
2760 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2761 || reg_mentioned_p (virtual_outgoing_args_rtx,
2762 structure_value_addr))
2763 && (args_size.var
2764 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2765 structure_value_addr = copy_to_reg (structure_value_addr);
2767 /* Tail calls can make things harder to debug, and we've traditionally
2768 pushed these optimizations into -O2. Don't try if we're already
2769 expanding a call, as that means we're an argument. Don't try if
2770 there's cleanups, as we know there's code to follow the call. */
2772 if (currently_expanding_call++ != 0
2773 || !flag_optimize_sibling_calls
2774 || args_size.var
2775 || dbg_cnt (tail_call) == false)
2776 try_tail_call = 0;
2778 /* Rest of purposes for tail call optimizations to fail. */
2779 if (!try_tail_call
2780 || !targetm.have_sibcall_epilogue ()
2781 /* Doing sibling call optimization needs some work, since
2782 structure_value_addr can be allocated on the stack.
2783 It does not seem worth the effort since few optimizable
2784 sibling calls will return a structure. */
2785 || structure_value_addr != NULL_RTX
2786 #ifdef REG_PARM_STACK_SPACE
2787 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2788 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2789 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2790 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl))
2791 #endif
2792 /* Check whether the target is able to optimize the call
2793 into a sibcall. */
2794 || !targetm.function_ok_for_sibcall (fndecl, exp)
2795 /* Functions that do not return exactly once may not be sibcall
2796 optimized. */
2797 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2798 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2799 /* If the called function is nested in the current one, it might access
2800 some of the caller's arguments, but could clobber them beforehand if
2801 the argument areas are shared. */
2802 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2803 /* If this function requires more stack slots than the current
2804 function, we cannot change it into a sibling call.
2805 crtl->args.pretend_args_size is not part of the
2806 stack allocated by our caller. */
2807 || args_size.constant > (crtl->args.size
2808 - crtl->args.pretend_args_size)
2809 /* If the callee pops its own arguments, then it must pop exactly
2810 the same number of arguments as the current function. */
2811 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2812 != targetm.calls.return_pops_args (current_function_decl,
2813 TREE_TYPE (current_function_decl),
2814 crtl->args.size))
2815 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2816 try_tail_call = 0;
2818 /* Check if caller and callee disagree in promotion of function
2819 return value. */
2820 if (try_tail_call)
2822 machine_mode caller_mode, caller_promoted_mode;
2823 machine_mode callee_mode, callee_promoted_mode;
2824 int caller_unsignedp, callee_unsignedp;
2825 tree caller_res = DECL_RESULT (current_function_decl);
2827 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2828 caller_mode = DECL_MODE (caller_res);
2829 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2830 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2831 caller_promoted_mode
2832 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2833 &caller_unsignedp,
2834 TREE_TYPE (current_function_decl), 1);
2835 callee_promoted_mode
2836 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2837 &callee_unsignedp,
2838 funtype, 1);
2839 if (caller_mode != VOIDmode
2840 && (caller_promoted_mode != callee_promoted_mode
2841 || ((caller_mode != caller_promoted_mode
2842 || callee_mode != callee_promoted_mode)
2843 && (caller_unsignedp != callee_unsignedp
2844 || GET_MODE_BITSIZE (caller_mode)
2845 < GET_MODE_BITSIZE (callee_mode)))))
2846 try_tail_call = 0;
2849 /* Ensure current function's preferred stack boundary is at least
2850 what we need. Stack alignment may also increase preferred stack
2851 boundary. */
2852 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2853 crtl->preferred_stack_boundary = preferred_stack_boundary;
2854 else
2855 preferred_stack_boundary = crtl->preferred_stack_boundary;
2857 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2859 /* We want to make two insn chains; one for a sibling call, the other
2860 for a normal call. We will select one of the two chains after
2861 initial RTL generation is complete. */
2862 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2864 int sibcall_failure = 0;
2865 /* We want to emit any pending stack adjustments before the tail
2866 recursion "call". That way we know any adjustment after the tail
2867 recursion call can be ignored if we indeed use the tail
2868 call expansion. */
2869 saved_pending_stack_adjust save;
2870 rtx_insn *insns, *before_call, *after_args;
2871 rtx next_arg_reg;
2873 if (pass == 0)
2875 /* State variables we need to save and restore between
2876 iterations. */
2877 save_pending_stack_adjust (&save);
2879 if (pass)
2880 flags &= ~ECF_SIBCALL;
2881 else
2882 flags |= ECF_SIBCALL;
2884 /* Other state variables that we must reinitialize each time
2885 through the loop (that are not initialized by the loop itself). */
2886 argblock = 0;
2887 call_fusage = 0;
2889 /* Start a new sequence for the normal call case.
2891 From this point on, if the sibling call fails, we want to set
2892 sibcall_failure instead of continuing the loop. */
2893 start_sequence ();
2895 /* Don't let pending stack adjusts add up to too much.
2896 Also, do all pending adjustments now if there is any chance
2897 this might be a call to alloca or if we are expanding a sibling
2898 call sequence.
2899 Also do the adjustments before a throwing call, otherwise
2900 exception handling can fail; PR 19225. */
2901 if (pending_stack_adjust >= 32
2902 || (pending_stack_adjust > 0
2903 && (flags & ECF_MAY_BE_ALLOCA))
2904 || (pending_stack_adjust > 0
2905 && flag_exceptions && !(flags & ECF_NOTHROW))
2906 || pass == 0)
2907 do_pending_stack_adjust ();
2909 /* Precompute any arguments as needed. */
2910 if (pass)
2911 precompute_arguments (num_actuals, args);
2913 /* Now we are about to start emitting insns that can be deleted
2914 if a libcall is deleted. */
2915 if (pass && (flags & ECF_MALLOC))
2916 start_sequence ();
2918 if (pass == 0 && crtl->stack_protect_guard)
2919 stack_protect_epilogue ();
2921 adjusted_args_size = args_size;
2922 /* Compute the actual size of the argument block required. The variable
2923 and constant sizes must be combined, the size may have to be rounded,
2924 and there may be a minimum required size. When generating a sibcall
2925 pattern, do not round up, since we'll be re-using whatever space our
2926 caller provided. */
2927 unadjusted_args_size
2928 = compute_argument_block_size (reg_parm_stack_space,
2929 &adjusted_args_size,
2930 fndecl, fntype,
2931 (pass == 0 ? 0
2932 : preferred_stack_boundary));
2934 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2936 /* The argument block when performing a sibling call is the
2937 incoming argument block. */
2938 if (pass == 0)
2940 argblock = crtl->args.internal_arg_pointer;
2941 if (STACK_GROWS_DOWNWARD)
2942 argblock
2943 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
2944 else
2945 argblock
2946 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
2948 stored_args_map = sbitmap_alloc (args_size.constant);
2949 bitmap_clear (stored_args_map);
2952 /* If we have no actual push instructions, or shouldn't use them,
2953 make space for all args right now. */
2954 else if (adjusted_args_size.var != 0)
2956 if (old_stack_level == 0)
2958 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2959 old_stack_pointer_delta = stack_pointer_delta;
2960 old_pending_adj = pending_stack_adjust;
2961 pending_stack_adjust = 0;
2962 /* stack_arg_under_construction says whether a stack arg is
2963 being constructed at the old stack level. Pushing the stack
2964 gets a clean outgoing argument block. */
2965 old_stack_arg_under_construction = stack_arg_under_construction;
2966 stack_arg_under_construction = 0;
2968 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2969 if (flag_stack_usage_info)
2970 current_function_has_unbounded_dynamic_stack_size = 1;
2972 else
2974 /* Note that we must go through the motions of allocating an argument
2975 block even if the size is zero because we may be storing args
2976 in the area reserved for register arguments, which may be part of
2977 the stack frame. */
2979 int needed = adjusted_args_size.constant;
2981 /* Store the maximum argument space used. It will be pushed by
2982 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2983 checking). */
2985 if (needed > crtl->outgoing_args_size)
2986 crtl->outgoing_args_size = needed;
2988 if (must_preallocate)
2990 if (ACCUMULATE_OUTGOING_ARGS)
2992 /* Since the stack pointer will never be pushed, it is
2993 possible for the evaluation of a parm to clobber
2994 something we have already written to the stack.
2995 Since most function calls on RISC machines do not use
2996 the stack, this is uncommon, but must work correctly.
2998 Therefore, we save any area of the stack that was already
2999 written and that we are using. Here we set up to do this
3000 by making a new stack usage map from the old one. The
3001 actual save will be done by store_one_arg.
3003 Another approach might be to try to reorder the argument
3004 evaluations to avoid this conflicting stack usage. */
3006 /* Since we will be writing into the entire argument area,
3007 the map must be allocated for its entire size, not just
3008 the part that is the responsibility of the caller. */
3009 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3010 needed += reg_parm_stack_space;
3012 if (ARGS_GROW_DOWNWARD)
3013 highest_outgoing_arg_in_use
3014 = MAX (initial_highest_arg_in_use, needed + 1);
3015 else
3016 highest_outgoing_arg_in_use
3017 = MAX (initial_highest_arg_in_use, needed);
3019 free (stack_usage_map_buf);
3020 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3021 stack_usage_map = stack_usage_map_buf;
3023 if (initial_highest_arg_in_use)
3024 memcpy (stack_usage_map, initial_stack_usage_map,
3025 initial_highest_arg_in_use);
3027 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3028 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3029 (highest_outgoing_arg_in_use
3030 - initial_highest_arg_in_use));
3031 needed = 0;
3033 /* The address of the outgoing argument list must not be
3034 copied to a register here, because argblock would be left
3035 pointing to the wrong place after the call to
3036 allocate_dynamic_stack_space below. */
3038 argblock = virtual_outgoing_args_rtx;
3040 else
3042 if (inhibit_defer_pop == 0)
3044 /* Try to reuse some or all of the pending_stack_adjust
3045 to get this space. */
3046 needed
3047 = (combine_pending_stack_adjustment_and_call
3048 (unadjusted_args_size,
3049 &adjusted_args_size,
3050 preferred_unit_stack_boundary));
3052 /* combine_pending_stack_adjustment_and_call computes
3053 an adjustment before the arguments are allocated.
3054 Account for them and see whether or not the stack
3055 needs to go up or down. */
3056 needed = unadjusted_args_size - needed;
3058 if (needed < 0)
3060 /* We're releasing stack space. */
3061 /* ??? We can avoid any adjustment at all if we're
3062 already aligned. FIXME. */
3063 pending_stack_adjust = -needed;
3064 do_pending_stack_adjust ();
3065 needed = 0;
3067 else
3068 /* We need to allocate space. We'll do that in
3069 push_block below. */
3070 pending_stack_adjust = 0;
3073 /* Special case this because overhead of `push_block' in
3074 this case is non-trivial. */
3075 if (needed == 0)
3076 argblock = virtual_outgoing_args_rtx;
3077 else
3079 argblock = push_block (GEN_INT (needed), 0, 0);
3080 if (ARGS_GROW_DOWNWARD)
3081 argblock = plus_constant (Pmode, argblock, needed);
3084 /* We only really need to call `copy_to_reg' in the case
3085 where push insns are going to be used to pass ARGBLOCK
3086 to a function call in ARGS. In that case, the stack
3087 pointer changes value from the allocation point to the
3088 call point, and hence the value of
3089 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3090 as well always do it. */
3091 argblock = copy_to_reg (argblock);
3096 if (ACCUMULATE_OUTGOING_ARGS)
3098 /* The save/restore code in store_one_arg handles all
3099 cases except one: a constructor call (including a C
3100 function returning a BLKmode struct) to initialize
3101 an argument. */
3102 if (stack_arg_under_construction)
3104 rtx push_size
3105 = GEN_INT (adjusted_args_size.constant
3106 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3107 : TREE_TYPE (fndecl))) ? 0
3108 : reg_parm_stack_space));
3109 if (old_stack_level == 0)
3111 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3112 old_stack_pointer_delta = stack_pointer_delta;
3113 old_pending_adj = pending_stack_adjust;
3114 pending_stack_adjust = 0;
3115 /* stack_arg_under_construction says whether a stack
3116 arg is being constructed at the old stack level.
3117 Pushing the stack gets a clean outgoing argument
3118 block. */
3119 old_stack_arg_under_construction
3120 = stack_arg_under_construction;
3121 stack_arg_under_construction = 0;
3122 /* Make a new map for the new argument list. */
3123 free (stack_usage_map_buf);
3124 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3125 stack_usage_map = stack_usage_map_buf;
3126 highest_outgoing_arg_in_use = 0;
3128 /* We can pass TRUE as the 4th argument because we just
3129 saved the stack pointer and will restore it right after
3130 the call. */
3131 allocate_dynamic_stack_space (push_size, 0,
3132 BIGGEST_ALIGNMENT, true);
3135 /* If argument evaluation might modify the stack pointer,
3136 copy the address of the argument list to a register. */
3137 for (i = 0; i < num_actuals; i++)
3138 if (args[i].pass_on_stack)
3140 argblock = copy_addr_to_reg (argblock);
3141 break;
3145 compute_argument_addresses (args, argblock, num_actuals);
3147 /* Stack is properly aligned, pops can't safely be deferred during
3148 the evaluation of the arguments. */
3149 NO_DEFER_POP;
3151 /* Precompute all register parameters. It isn't safe to compute
3152 anything once we have started filling any specific hard regs.
3153 TLS symbols sometimes need a call to resolve. Precompute
3154 register parameters before any stack pointer manipulation
3155 to avoid unaligned stack in the called function. */
3156 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3158 OK_DEFER_POP;
3160 /* Perform stack alignment before the first push (the last arg). */
3161 if (argblock == 0
3162 && adjusted_args_size.constant > reg_parm_stack_space
3163 && adjusted_args_size.constant != unadjusted_args_size)
3165 /* When the stack adjustment is pending, we get better code
3166 by combining the adjustments. */
3167 if (pending_stack_adjust
3168 && ! inhibit_defer_pop)
3170 pending_stack_adjust
3171 = (combine_pending_stack_adjustment_and_call
3172 (unadjusted_args_size,
3173 &adjusted_args_size,
3174 preferred_unit_stack_boundary));
3175 do_pending_stack_adjust ();
3177 else if (argblock == 0)
3178 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3179 - unadjusted_args_size));
3181 /* Now that the stack is properly aligned, pops can't safely
3182 be deferred during the evaluation of the arguments. */
3183 NO_DEFER_POP;
3185 /* Record the maximum pushed stack space size. We need to delay
3186 doing it this far to take into account the optimization done
3187 by combine_pending_stack_adjustment_and_call. */
3188 if (flag_stack_usage_info
3189 && !ACCUMULATE_OUTGOING_ARGS
3190 && pass
3191 && adjusted_args_size.var == 0)
3193 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3194 if (pushed > current_function_pushed_stack_size)
3195 current_function_pushed_stack_size = pushed;
3198 funexp = rtx_for_function_call (fndecl, addr);
3200 if (CALL_EXPR_STATIC_CHAIN (exp))
3201 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3202 else
3203 static_chain_value = 0;
3205 #ifdef REG_PARM_STACK_SPACE
3206 /* Save the fixed argument area if it's part of the caller's frame and
3207 is clobbered by argument setup for this call. */
3208 if (ACCUMULATE_OUTGOING_ARGS && pass)
3209 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3210 &low_to_save, &high_to_save);
3211 #endif
3213 /* Now store (and compute if necessary) all non-register parms.
3214 These come before register parms, since they can require block-moves,
3215 which could clobber the registers used for register parms.
3216 Parms which have partial registers are not stored here,
3217 but we do preallocate space here if they want that. */
3219 for (i = 0; i < num_actuals; i++)
3221 /* Delay bounds until all other args are stored. */
3222 if (POINTER_BOUNDS_P (args[i].tree_value))
3223 continue;
3224 else if (args[i].reg == 0 || args[i].pass_on_stack)
3226 rtx_insn *before_arg = get_last_insn ();
3228 /* We don't allow passing huge (> 2^30 B) arguments
3229 by value. It would cause an overflow later on. */
3230 if (adjusted_args_size.constant
3231 >= (1 << (HOST_BITS_PER_INT - 2)))
3233 sorry ("passing too large argument on stack");
3234 continue;
3237 if (store_one_arg (&args[i], argblock, flags,
3238 adjusted_args_size.var != 0,
3239 reg_parm_stack_space)
3240 || (pass == 0
3241 && check_sibcall_argument_overlap (before_arg,
3242 &args[i], 1)))
3243 sibcall_failure = 1;
3246 if (args[i].stack)
3247 call_fusage
3248 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3249 gen_rtx_USE (VOIDmode, args[i].stack),
3250 call_fusage);
3253 /* If we have a parm that is passed in registers but not in memory
3254 and whose alignment does not permit a direct copy into registers,
3255 make a group of pseudos that correspond to each register that we
3256 will later fill. */
3257 if (STRICT_ALIGNMENT)
3258 store_unaligned_arguments_into_pseudos (args, num_actuals);
3260 /* Now store any partially-in-registers parm.
3261 This is the last place a block-move can happen. */
3262 if (reg_parm_seen)
3263 for (i = 0; i < num_actuals; i++)
3264 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3266 rtx_insn *before_arg = get_last_insn ();
3268 /* On targets with weird calling conventions (e.g. PA) it's
3269 hard to ensure that all cases of argument overlap between
3270 stack and registers work. Play it safe and bail out. */
3271 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3273 sibcall_failure = 1;
3274 break;
3277 if (store_one_arg (&args[i], argblock, flags,
3278 adjusted_args_size.var != 0,
3279 reg_parm_stack_space)
3280 || (pass == 0
3281 && check_sibcall_argument_overlap (before_arg,
3282 &args[i], 1)))
3283 sibcall_failure = 1;
3286 bool any_regs = false;
3287 for (i = 0; i < num_actuals; i++)
3288 if (args[i].reg != NULL_RTX)
3290 any_regs = true;
3291 targetm.calls.call_args (args[i].reg, funtype);
3293 if (!any_regs)
3294 targetm.calls.call_args (pc_rtx, funtype);
3296 /* Figure out the register where the value, if any, will come back. */
3297 valreg = 0;
3298 valbnd = 0;
3299 if (TYPE_MODE (rettype) != VOIDmode
3300 && ! structure_value_addr)
3302 if (pcc_struct_value)
3304 valreg = hard_function_value (build_pointer_type (rettype),
3305 fndecl, NULL, (pass == 0));
3306 if (CALL_WITH_BOUNDS_P (exp))
3307 valbnd = targetm.calls.
3308 chkp_function_value_bounds (build_pointer_type (rettype),
3309 fndecl, (pass == 0));
3311 else
3313 valreg = hard_function_value (rettype, fndecl, fntype,
3314 (pass == 0));
3315 if (CALL_WITH_BOUNDS_P (exp))
3316 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3317 fndecl,
3318 (pass == 0));
3321 /* If VALREG is a PARALLEL whose first member has a zero
3322 offset, use that. This is for targets such as m68k that
3323 return the same value in multiple places. */
3324 if (GET_CODE (valreg) == PARALLEL)
3326 rtx elem = XVECEXP (valreg, 0, 0);
3327 rtx where = XEXP (elem, 0);
3328 rtx offset = XEXP (elem, 1);
3329 if (offset == const0_rtx
3330 && GET_MODE (where) == GET_MODE (valreg))
3331 valreg = where;
3335 /* Store all bounds not passed in registers. */
3336 for (i = 0; i < num_actuals; i++)
3338 if (POINTER_BOUNDS_P (args[i].tree_value)
3339 && !args[i].reg)
3340 store_bounds (&args[i],
3341 args[i].pointer_arg == -1
3342 ? NULL
3343 : &args[args[i].pointer_arg]);
3346 /* If register arguments require space on the stack and stack space
3347 was not preallocated, allocate stack space here for arguments
3348 passed in registers. */
3349 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3350 && !ACCUMULATE_OUTGOING_ARGS
3351 && must_preallocate == 0 && reg_parm_stack_space > 0)
3352 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3354 /* Pass the function the address in which to return a
3355 structure value. */
3356 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3358 structure_value_addr
3359 = convert_memory_address (Pmode, structure_value_addr);
3360 emit_move_insn (struct_value,
3361 force_reg (Pmode,
3362 force_operand (structure_value_addr,
3363 NULL_RTX)));
3365 if (REG_P (struct_value))
3366 use_reg (&call_fusage, struct_value);
3369 after_args = get_last_insn ();
3370 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3371 static_chain_value, &call_fusage,
3372 reg_parm_seen, pass == 0);
3374 load_register_parameters (args, num_actuals, &call_fusage, flags,
3375 pass == 0, &sibcall_failure);
3377 /* Save a pointer to the last insn before the call, so that we can
3378 later safely search backwards to find the CALL_INSN. */
3379 before_call = get_last_insn ();
3381 /* Set up next argument register. For sibling calls on machines
3382 with register windows this should be the incoming register. */
3383 if (pass == 0)
3384 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3385 VOIDmode,
3386 void_type_node,
3387 true);
3388 else
3389 next_arg_reg = targetm.calls.function_arg (args_so_far,
3390 VOIDmode, void_type_node,
3391 true);
3393 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3395 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3396 arg_nr = num_actuals - arg_nr - 1;
3397 if (arg_nr >= 0
3398 && arg_nr < num_actuals
3399 && args[arg_nr].reg
3400 && valreg
3401 && REG_P (valreg)
3402 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3403 call_fusage
3404 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3405 gen_rtx_SET (valreg, args[arg_nr].reg),
3406 call_fusage);
3408 /* All arguments and registers used for the call must be set up by
3409 now! */
3411 /* Stack must be properly aligned now. */
3412 gcc_assert (!pass
3413 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3415 /* Generate the actual call instruction. */
3416 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3417 adjusted_args_size.constant, struct_value_size,
3418 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3419 flags, args_so_far);
3421 if (flag_ipa_ra)
3423 rtx_call_insn *last;
3424 rtx datum = NULL_RTX;
3425 if (fndecl != NULL_TREE)
3427 datum = XEXP (DECL_RTL (fndecl), 0);
3428 gcc_assert (datum != NULL_RTX
3429 && GET_CODE (datum) == SYMBOL_REF);
3431 last = last_call_insn ();
3432 add_reg_note (last, REG_CALL_DECL, datum);
3435 /* If the call setup or the call itself overlaps with anything
3436 of the argument setup we probably clobbered our call address.
3437 In that case we can't do sibcalls. */
3438 if (pass == 0
3439 && check_sibcall_argument_overlap (after_args, 0, 0))
3440 sibcall_failure = 1;
3442 /* If a non-BLKmode value is returned at the most significant end
3443 of a register, shift the register right by the appropriate amount
3444 and update VALREG accordingly. BLKmode values are handled by the
3445 group load/store machinery below. */
3446 if (!structure_value_addr
3447 && !pcc_struct_value
3448 && TYPE_MODE (rettype) != VOIDmode
3449 && TYPE_MODE (rettype) != BLKmode
3450 && REG_P (valreg)
3451 && targetm.calls.return_in_msb (rettype))
3453 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3454 sibcall_failure = 1;
3455 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3458 if (pass && (flags & ECF_MALLOC))
3460 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3461 rtx_insn *last, *insns;
3463 /* The return value from a malloc-like function is a pointer. */
3464 if (TREE_CODE (rettype) == POINTER_TYPE)
3465 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3467 emit_move_insn (temp, valreg);
3469 /* The return value from a malloc-like function can not alias
3470 anything else. */
3471 last = get_last_insn ();
3472 add_reg_note (last, REG_NOALIAS, temp);
3474 /* Write out the sequence. */
3475 insns = get_insns ();
3476 end_sequence ();
3477 emit_insn (insns);
3478 valreg = temp;
3481 /* For calls to `setjmp', etc., inform
3482 function.c:setjmp_warnings that it should complain if
3483 nonvolatile values are live. For functions that cannot
3484 return, inform flow that control does not fall through. */
3486 if ((flags & ECF_NORETURN) || pass == 0)
3488 /* The barrier must be emitted
3489 immediately after the CALL_INSN. Some ports emit more
3490 than just a CALL_INSN above, so we must search for it here. */
3492 rtx_insn *last = get_last_insn ();
3493 while (!CALL_P (last))
3495 last = PREV_INSN (last);
3496 /* There was no CALL_INSN? */
3497 gcc_assert (last != before_call);
3500 emit_barrier_after (last);
3502 /* Stack adjustments after a noreturn call are dead code.
3503 However when NO_DEFER_POP is in effect, we must preserve
3504 stack_pointer_delta. */
3505 if (inhibit_defer_pop == 0)
3507 stack_pointer_delta = old_stack_allocated;
3508 pending_stack_adjust = 0;
3512 /* If value type not void, return an rtx for the value. */
3514 if (TYPE_MODE (rettype) == VOIDmode
3515 || ignore)
3516 target = const0_rtx;
3517 else if (structure_value_addr)
3519 if (target == 0 || !MEM_P (target))
3521 target
3522 = gen_rtx_MEM (TYPE_MODE (rettype),
3523 memory_address (TYPE_MODE (rettype),
3524 structure_value_addr));
3525 set_mem_attributes (target, rettype, 1);
3528 else if (pcc_struct_value)
3530 /* This is the special C++ case where we need to
3531 know what the true target was. We take care to
3532 never use this value more than once in one expression. */
3533 target = gen_rtx_MEM (TYPE_MODE (rettype),
3534 copy_to_reg (valreg));
3535 set_mem_attributes (target, rettype, 1);
3537 /* Handle calls that return values in multiple non-contiguous locations.
3538 The Irix 6 ABI has examples of this. */
3539 else if (GET_CODE (valreg) == PARALLEL)
3541 if (target == 0)
3542 target = emit_group_move_into_temps (valreg);
3543 else if (rtx_equal_p (target, valreg))
3545 else if (GET_CODE (target) == PARALLEL)
3546 /* Handle the result of a emit_group_move_into_temps
3547 call in the previous pass. */
3548 emit_group_move (target, valreg);
3549 else
3550 emit_group_store (target, valreg, rettype,
3551 int_size_in_bytes (rettype));
3553 else if (target
3554 && GET_MODE (target) == TYPE_MODE (rettype)
3555 && GET_MODE (target) == GET_MODE (valreg))
3557 bool may_overlap = false;
3559 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3560 reg to a plain register. */
3561 if (!REG_P (target) || HARD_REGISTER_P (target))
3562 valreg = avoid_likely_spilled_reg (valreg);
3564 /* If TARGET is a MEM in the argument area, and we have
3565 saved part of the argument area, then we can't store
3566 directly into TARGET as it may get overwritten when we
3567 restore the argument save area below. Don't work too
3568 hard though and simply force TARGET to a register if it
3569 is a MEM; the optimizer is quite likely to sort it out. */
3570 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3571 for (i = 0; i < num_actuals; i++)
3572 if (args[i].save_area)
3574 may_overlap = true;
3575 break;
3578 if (may_overlap)
3579 target = copy_to_reg (valreg);
3580 else
3582 /* TARGET and VALREG cannot be equal at this point
3583 because the latter would not have
3584 REG_FUNCTION_VALUE_P true, while the former would if
3585 it were referring to the same register.
3587 If they refer to the same register, this move will be
3588 a no-op, except when function inlining is being
3589 done. */
3590 emit_move_insn (target, valreg);
3592 /* If we are setting a MEM, this code must be executed.
3593 Since it is emitted after the call insn, sibcall
3594 optimization cannot be performed in that case. */
3595 if (MEM_P (target))
3596 sibcall_failure = 1;
3599 else
3600 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3602 /* If we promoted this return value, make the proper SUBREG.
3603 TARGET might be const0_rtx here, so be careful. */
3604 if (REG_P (target)
3605 && TYPE_MODE (rettype) != BLKmode
3606 && GET_MODE (target) != TYPE_MODE (rettype))
3608 tree type = rettype;
3609 int unsignedp = TYPE_UNSIGNED (type);
3610 int offset = 0;
3611 machine_mode pmode;
3613 /* Ensure we promote as expected, and get the new unsignedness. */
3614 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3615 funtype, 1);
3616 gcc_assert (GET_MODE (target) == pmode);
3618 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3619 && (GET_MODE_SIZE (GET_MODE (target))
3620 > GET_MODE_SIZE (TYPE_MODE (type))))
3622 offset = GET_MODE_SIZE (GET_MODE (target))
3623 - GET_MODE_SIZE (TYPE_MODE (type));
3624 if (! BYTES_BIG_ENDIAN)
3625 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3626 else if (! WORDS_BIG_ENDIAN)
3627 offset %= UNITS_PER_WORD;
3630 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3631 SUBREG_PROMOTED_VAR_P (target) = 1;
3632 SUBREG_PROMOTED_SET (target, unsignedp);
3635 /* If size of args is variable or this was a constructor call for a stack
3636 argument, restore saved stack-pointer value. */
3638 if (old_stack_level)
3640 rtx_insn *prev = get_last_insn ();
3642 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3643 stack_pointer_delta = old_stack_pointer_delta;
3645 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3647 pending_stack_adjust = old_pending_adj;
3648 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3649 stack_arg_under_construction = old_stack_arg_under_construction;
3650 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3651 stack_usage_map = initial_stack_usage_map;
3652 sibcall_failure = 1;
3654 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3656 #ifdef REG_PARM_STACK_SPACE
3657 if (save_area)
3658 restore_fixed_argument_area (save_area, argblock,
3659 high_to_save, low_to_save);
3660 #endif
3662 /* If we saved any argument areas, restore them. */
3663 for (i = 0; i < num_actuals; i++)
3664 if (args[i].save_area)
3666 machine_mode save_mode = GET_MODE (args[i].save_area);
3667 rtx stack_area
3668 = gen_rtx_MEM (save_mode,
3669 memory_address (save_mode,
3670 XEXP (args[i].stack_slot, 0)));
3672 if (save_mode != BLKmode)
3673 emit_move_insn (stack_area, args[i].save_area);
3674 else
3675 emit_block_move (stack_area, args[i].save_area,
3676 GEN_INT (args[i].locate.size.constant),
3677 BLOCK_OP_CALL_PARM);
3680 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3681 stack_usage_map = initial_stack_usage_map;
3684 /* If this was alloca, record the new stack level. */
3685 if (flags & ECF_MAY_BE_ALLOCA)
3686 record_new_stack_level ();
3688 /* Free up storage we no longer need. */
3689 for (i = 0; i < num_actuals; ++i)
3690 free (args[i].aligned_regs);
3692 targetm.calls.end_call_args ();
3694 insns = get_insns ();
3695 end_sequence ();
3697 if (pass == 0)
3699 tail_call_insns = insns;
3701 /* Restore the pending stack adjustment now that we have
3702 finished generating the sibling call sequence. */
3704 restore_pending_stack_adjust (&save);
3706 /* Prepare arg structure for next iteration. */
3707 for (i = 0; i < num_actuals; i++)
3709 args[i].value = 0;
3710 args[i].aligned_regs = 0;
3711 args[i].stack = 0;
3714 sbitmap_free (stored_args_map);
3715 internal_arg_pointer_exp_state.scan_start = NULL;
3716 internal_arg_pointer_exp_state.cache.release ();
3718 else
3720 normal_call_insns = insns;
3722 /* Verify that we've deallocated all the stack we used. */
3723 gcc_assert ((flags & ECF_NORETURN)
3724 || (old_stack_allocated
3725 == stack_pointer_delta - pending_stack_adjust));
3728 /* If something prevents making this a sibling call,
3729 zero out the sequence. */
3730 if (sibcall_failure)
3731 tail_call_insns = NULL;
3732 else
3733 break;
3736 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3737 arguments too, as argument area is now clobbered by the call. */
3738 if (tail_call_insns)
3740 emit_insn (tail_call_insns);
3741 crtl->tail_call_emit = true;
3743 else
3744 emit_insn (normal_call_insns);
3746 currently_expanding_call--;
3748 free (stack_usage_map_buf);
3750 /* Join result with returned bounds so caller may use them if needed. */
3751 target = chkp_join_splitted_slot (target, valbnd);
3753 return target;
3756 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3757 this function's incoming arguments.
3759 At the start of RTL generation we know the only REG_EQUIV notes
3760 in the rtl chain are those for incoming arguments, so we can look
3761 for REG_EQUIV notes between the start of the function and the
3762 NOTE_INSN_FUNCTION_BEG.
3764 This is (slight) overkill. We could keep track of the highest
3765 argument we clobber and be more selective in removing notes, but it
3766 does not seem to be worth the effort. */
3768 void
3769 fixup_tail_calls (void)
3771 rtx_insn *insn;
3773 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3775 rtx note;
3777 /* There are never REG_EQUIV notes for the incoming arguments
3778 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3779 if (NOTE_P (insn)
3780 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3781 break;
3783 note = find_reg_note (insn, REG_EQUIV, 0);
3784 if (note)
3785 remove_note (insn, note);
3786 note = find_reg_note (insn, REG_EQUIV, 0);
3787 gcc_assert (!note);
3791 /* Traverse a list of TYPES and expand all complex types into their
3792 components. */
3793 static tree
3794 split_complex_types (tree types)
3796 tree p;
3798 /* Before allocating memory, check for the common case of no complex. */
3799 for (p = types; p; p = TREE_CHAIN (p))
3801 tree type = TREE_VALUE (p);
3802 if (TREE_CODE (type) == COMPLEX_TYPE
3803 && targetm.calls.split_complex_arg (type))
3804 goto found;
3806 return types;
3808 found:
3809 types = copy_list (types);
3811 for (p = types; p; p = TREE_CHAIN (p))
3813 tree complex_type = TREE_VALUE (p);
3815 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3816 && targetm.calls.split_complex_arg (complex_type))
3818 tree next, imag;
3820 /* Rewrite complex type with component type. */
3821 TREE_VALUE (p) = TREE_TYPE (complex_type);
3822 next = TREE_CHAIN (p);
3824 /* Add another component type for the imaginary part. */
3825 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3826 TREE_CHAIN (p) = imag;
3827 TREE_CHAIN (imag) = next;
3829 /* Skip the newly created node. */
3830 p = TREE_CHAIN (p);
3834 return types;
3837 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3838 The RETVAL parameter specifies whether return value needs to be saved, other
3839 parameters are documented in the emit_library_call function below. */
3841 static rtx
3842 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3843 enum libcall_type fn_type,
3844 machine_mode outmode, int nargs, va_list p)
3846 /* Total size in bytes of all the stack-parms scanned so far. */
3847 struct args_size args_size;
3848 /* Size of arguments before any adjustments (such as rounding). */
3849 struct args_size original_args_size;
3850 int argnum;
3851 rtx fun;
3852 /* Todo, choose the correct decl type of orgfun. Sadly this information
3853 isn't present here, so we default to native calling abi here. */
3854 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3855 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3856 int count;
3857 rtx argblock = 0;
3858 CUMULATIVE_ARGS args_so_far_v;
3859 cumulative_args_t args_so_far;
3860 struct arg
3862 rtx value;
3863 machine_mode mode;
3864 rtx reg;
3865 int partial;
3866 struct locate_and_pad_arg_data locate;
3867 rtx save_area;
3869 struct arg *argvec;
3870 int old_inhibit_defer_pop = inhibit_defer_pop;
3871 rtx call_fusage = 0;
3872 rtx mem_value = 0;
3873 rtx valreg;
3874 int pcc_struct_value = 0;
3875 int struct_value_size = 0;
3876 int flags;
3877 int reg_parm_stack_space = 0;
3878 int needed;
3879 rtx_insn *before_call;
3880 bool have_push_fusage;
3881 tree tfom; /* type_for_mode (outmode, 0) */
3883 #ifdef REG_PARM_STACK_SPACE
3884 /* Define the boundary of the register parm stack space that needs to be
3885 save, if any. */
3886 int low_to_save = 0, high_to_save = 0;
3887 rtx save_area = 0; /* Place that it is saved. */
3888 #endif
3890 /* Size of the stack reserved for parameter registers. */
3891 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3892 char *initial_stack_usage_map = stack_usage_map;
3893 char *stack_usage_map_buf = NULL;
3895 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3897 #ifdef REG_PARM_STACK_SPACE
3898 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3899 #endif
3901 /* By default, library functions can not throw. */
3902 flags = ECF_NOTHROW;
3904 switch (fn_type)
3906 case LCT_NORMAL:
3907 break;
3908 case LCT_CONST:
3909 flags |= ECF_CONST;
3910 break;
3911 case LCT_PURE:
3912 flags |= ECF_PURE;
3913 break;
3914 case LCT_NORETURN:
3915 flags |= ECF_NORETURN;
3916 break;
3917 case LCT_THROW:
3918 flags = ECF_NORETURN;
3919 break;
3920 case LCT_RETURNS_TWICE:
3921 flags = ECF_RETURNS_TWICE;
3922 break;
3924 fun = orgfun;
3926 /* Ensure current function's preferred stack boundary is at least
3927 what we need. */
3928 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3929 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3931 /* If this kind of value comes back in memory,
3932 decide where in memory it should come back. */
3933 if (outmode != VOIDmode)
3935 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3936 if (aggregate_value_p (tfom, 0))
3938 #ifdef PCC_STATIC_STRUCT_RETURN
3939 rtx pointer_reg
3940 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3941 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3942 pcc_struct_value = 1;
3943 if (value == 0)
3944 value = gen_reg_rtx (outmode);
3945 #else /* not PCC_STATIC_STRUCT_RETURN */
3946 struct_value_size = GET_MODE_SIZE (outmode);
3947 if (value != 0 && MEM_P (value))
3948 mem_value = value;
3949 else
3950 mem_value = assign_temp (tfom, 1, 1);
3951 #endif
3952 /* This call returns a big structure. */
3953 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3956 else
3957 tfom = void_type_node;
3959 /* ??? Unfinished: must pass the memory address as an argument. */
3961 /* Copy all the libcall-arguments out of the varargs data
3962 and into a vector ARGVEC.
3964 Compute how to pass each argument. We only support a very small subset
3965 of the full argument passing conventions to limit complexity here since
3966 library functions shouldn't have many args. */
3968 argvec = XALLOCAVEC (struct arg, nargs + 1);
3969 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3971 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3972 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3973 #else
3974 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3975 #endif
3976 args_so_far = pack_cumulative_args (&args_so_far_v);
3978 args_size.constant = 0;
3979 args_size.var = 0;
3981 count = 0;
3983 push_temp_slots ();
3985 /* If there's a structure value address to be passed,
3986 either pass it in the special place, or pass it as an extra argument. */
3987 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3989 rtx addr = XEXP (mem_value, 0);
3991 nargs++;
3993 /* Make sure it is a reasonable operand for a move or push insn. */
3994 if (!REG_P (addr) && !MEM_P (addr)
3995 && !(CONSTANT_P (addr)
3996 && targetm.legitimate_constant_p (Pmode, addr)))
3997 addr = force_operand (addr, NULL_RTX);
3999 argvec[count].value = addr;
4000 argvec[count].mode = Pmode;
4001 argvec[count].partial = 0;
4003 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4004 Pmode, NULL_TREE, true);
4005 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4006 NULL_TREE, 1) == 0);
4008 locate_and_pad_parm (Pmode, NULL_TREE,
4009 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4011 #else
4012 argvec[count].reg != 0,
4013 #endif
4014 reg_parm_stack_space, 0,
4015 NULL_TREE, &args_size, &argvec[count].locate);
4017 if (argvec[count].reg == 0 || argvec[count].partial != 0
4018 || reg_parm_stack_space > 0)
4019 args_size.constant += argvec[count].locate.size.constant;
4021 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4023 count++;
4026 for (; count < nargs; count++)
4028 rtx val = va_arg (p, rtx);
4029 machine_mode mode = (machine_mode) va_arg (p, int);
4030 int unsigned_p = 0;
4032 /* We cannot convert the arg value to the mode the library wants here;
4033 must do it earlier where we know the signedness of the arg. */
4034 gcc_assert (mode != BLKmode
4035 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4037 /* Make sure it is a reasonable operand for a move or push insn. */
4038 if (!REG_P (val) && !MEM_P (val)
4039 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4040 val = force_operand (val, NULL_RTX);
4042 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4044 rtx slot;
4045 int must_copy
4046 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4048 /* If this was a CONST function, it is now PURE since it now
4049 reads memory. */
4050 if (flags & ECF_CONST)
4052 flags &= ~ECF_CONST;
4053 flags |= ECF_PURE;
4056 if (MEM_P (val) && !must_copy)
4058 tree val_expr = MEM_EXPR (val);
4059 if (val_expr)
4060 mark_addressable (val_expr);
4061 slot = val;
4063 else
4065 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4066 1, 1);
4067 emit_move_insn (slot, val);
4070 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4071 gen_rtx_USE (VOIDmode, slot),
4072 call_fusage);
4073 if (must_copy)
4074 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4075 gen_rtx_CLOBBER (VOIDmode,
4076 slot),
4077 call_fusage);
4079 mode = Pmode;
4080 val = force_operand (XEXP (slot, 0), NULL_RTX);
4083 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4084 argvec[count].mode = mode;
4085 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4086 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4087 NULL_TREE, true);
4089 argvec[count].partial
4090 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4092 if (argvec[count].reg == 0
4093 || argvec[count].partial != 0
4094 || reg_parm_stack_space > 0)
4096 locate_and_pad_parm (mode, NULL_TREE,
4097 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4099 #else
4100 argvec[count].reg != 0,
4101 #endif
4102 reg_parm_stack_space, argvec[count].partial,
4103 NULL_TREE, &args_size, &argvec[count].locate);
4104 args_size.constant += argvec[count].locate.size.constant;
4105 gcc_assert (!argvec[count].locate.size.var);
4107 #ifdef BLOCK_REG_PADDING
4108 else
4109 /* The argument is passed entirely in registers. See at which
4110 end it should be padded. */
4111 argvec[count].locate.where_pad =
4112 BLOCK_REG_PADDING (mode, NULL_TREE,
4113 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4114 #endif
4116 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4119 /* If this machine requires an external definition for library
4120 functions, write one out. */
4121 assemble_external_libcall (fun);
4123 original_args_size = args_size;
4124 args_size.constant = (((args_size.constant
4125 + stack_pointer_delta
4126 + STACK_BYTES - 1)
4127 / STACK_BYTES
4128 * STACK_BYTES)
4129 - stack_pointer_delta);
4131 args_size.constant = MAX (args_size.constant,
4132 reg_parm_stack_space);
4134 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4135 args_size.constant -= reg_parm_stack_space;
4137 if (args_size.constant > crtl->outgoing_args_size)
4138 crtl->outgoing_args_size = args_size.constant;
4140 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4142 int pushed = args_size.constant + pending_stack_adjust;
4143 if (pushed > current_function_pushed_stack_size)
4144 current_function_pushed_stack_size = pushed;
4147 if (ACCUMULATE_OUTGOING_ARGS)
4149 /* Since the stack pointer will never be pushed, it is possible for
4150 the evaluation of a parm to clobber something we have already
4151 written to the stack. Since most function calls on RISC machines
4152 do not use the stack, this is uncommon, but must work correctly.
4154 Therefore, we save any area of the stack that was already written
4155 and that we are using. Here we set up to do this by making a new
4156 stack usage map from the old one.
4158 Another approach might be to try to reorder the argument
4159 evaluations to avoid this conflicting stack usage. */
4161 needed = args_size.constant;
4163 /* Since we will be writing into the entire argument area, the
4164 map must be allocated for its entire size, not just the part that
4165 is the responsibility of the caller. */
4166 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4167 needed += reg_parm_stack_space;
4169 if (ARGS_GROW_DOWNWARD)
4170 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4171 needed + 1);
4172 else
4173 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4175 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4176 stack_usage_map = stack_usage_map_buf;
4178 if (initial_highest_arg_in_use)
4179 memcpy (stack_usage_map, initial_stack_usage_map,
4180 initial_highest_arg_in_use);
4182 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4183 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4184 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4185 needed = 0;
4187 /* We must be careful to use virtual regs before they're instantiated,
4188 and real regs afterwards. Loop optimization, for example, can create
4189 new libcalls after we've instantiated the virtual regs, and if we
4190 use virtuals anyway, they won't match the rtl patterns. */
4192 if (virtuals_instantiated)
4193 argblock = plus_constant (Pmode, stack_pointer_rtx,
4194 STACK_POINTER_OFFSET);
4195 else
4196 argblock = virtual_outgoing_args_rtx;
4198 else
4200 if (!PUSH_ARGS)
4201 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4204 /* We push args individually in reverse order, perform stack alignment
4205 before the first push (the last arg). */
4206 if (argblock == 0)
4207 anti_adjust_stack (GEN_INT (args_size.constant
4208 - original_args_size.constant));
4210 argnum = nargs - 1;
4212 #ifdef REG_PARM_STACK_SPACE
4213 if (ACCUMULATE_OUTGOING_ARGS)
4215 /* The argument list is the property of the called routine and it
4216 may clobber it. If the fixed area has been used for previous
4217 parameters, we must save and restore it. */
4218 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4219 &low_to_save, &high_to_save);
4221 #endif
4223 /* When expanding a normal call, args are stored in push order,
4224 which is the reverse of what we have here. */
4225 bool any_regs = false;
4226 for (int i = nargs; i-- > 0; )
4227 if (argvec[i].reg != NULL_RTX)
4229 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4230 any_regs = true;
4232 if (!any_regs)
4233 targetm.calls.call_args (pc_rtx, NULL_TREE);
4235 /* Push the args that need to be pushed. */
4237 have_push_fusage = false;
4239 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4240 are to be pushed. */
4241 for (count = 0; count < nargs; count++, argnum--)
4243 machine_mode mode = argvec[argnum].mode;
4244 rtx val = argvec[argnum].value;
4245 rtx reg = argvec[argnum].reg;
4246 int partial = argvec[argnum].partial;
4247 unsigned int parm_align = argvec[argnum].locate.boundary;
4248 int lower_bound = 0, upper_bound = 0, i;
4250 if (! (reg != 0 && partial == 0))
4252 rtx use;
4254 if (ACCUMULATE_OUTGOING_ARGS)
4256 /* If this is being stored into a pre-allocated, fixed-size,
4257 stack area, save any previous data at that location. */
4259 if (ARGS_GROW_DOWNWARD)
4261 /* stack_slot is negative, but we want to index stack_usage_map
4262 with positive values. */
4263 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4264 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4266 else
4268 lower_bound = argvec[argnum].locate.slot_offset.constant;
4269 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4272 i = lower_bound;
4273 /* Don't worry about things in the fixed argument area;
4274 it has already been saved. */
4275 if (i < reg_parm_stack_space)
4276 i = reg_parm_stack_space;
4277 while (i < upper_bound && stack_usage_map[i] == 0)
4278 i++;
4280 if (i < upper_bound)
4282 /* We need to make a save area. */
4283 unsigned int size
4284 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4285 machine_mode save_mode
4286 = mode_for_size (size, MODE_INT, 1);
4287 rtx adr
4288 = plus_constant (Pmode, argblock,
4289 argvec[argnum].locate.offset.constant);
4290 rtx stack_area
4291 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4293 if (save_mode == BLKmode)
4295 argvec[argnum].save_area
4296 = assign_stack_temp (BLKmode,
4297 argvec[argnum].locate.size.constant
4300 emit_block_move (validize_mem
4301 (copy_rtx (argvec[argnum].save_area)),
4302 stack_area,
4303 GEN_INT (argvec[argnum].locate.size.constant),
4304 BLOCK_OP_CALL_PARM);
4306 else
4308 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4310 emit_move_insn (argvec[argnum].save_area, stack_area);
4315 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4316 partial, reg, 0, argblock,
4317 GEN_INT (argvec[argnum].locate.offset.constant),
4318 reg_parm_stack_space,
4319 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4321 /* Now mark the segment we just used. */
4322 if (ACCUMULATE_OUTGOING_ARGS)
4323 for (i = lower_bound; i < upper_bound; i++)
4324 stack_usage_map[i] = 1;
4326 NO_DEFER_POP;
4328 /* Indicate argument access so that alias.c knows that these
4329 values are live. */
4330 if (argblock)
4331 use = plus_constant (Pmode, argblock,
4332 argvec[argnum].locate.offset.constant);
4333 else if (have_push_fusage)
4334 continue;
4335 else
4337 /* When arguments are pushed, trying to tell alias.c where
4338 exactly this argument is won't work, because the
4339 auto-increment causes confusion. So we merely indicate
4340 that we access something with a known mode somewhere on
4341 the stack. */
4342 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4343 gen_rtx_SCRATCH (Pmode));
4344 have_push_fusage = true;
4346 use = gen_rtx_MEM (argvec[argnum].mode, use);
4347 use = gen_rtx_USE (VOIDmode, use);
4348 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4352 argnum = nargs - 1;
4354 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4356 /* Now load any reg parms into their regs. */
4358 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4359 are to be pushed. */
4360 for (count = 0; count < nargs; count++, argnum--)
4362 machine_mode mode = argvec[argnum].mode;
4363 rtx val = argvec[argnum].value;
4364 rtx reg = argvec[argnum].reg;
4365 int partial = argvec[argnum].partial;
4366 #ifdef BLOCK_REG_PADDING
4367 int size = 0;
4368 #endif
4370 /* Handle calls that pass values in multiple non-contiguous
4371 locations. The PA64 has examples of this for library calls. */
4372 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4373 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4374 else if (reg != 0 && partial == 0)
4376 emit_move_insn (reg, val);
4377 #ifdef BLOCK_REG_PADDING
4378 size = GET_MODE_SIZE (argvec[argnum].mode);
4380 /* Copied from load_register_parameters. */
4382 /* Handle case where we have a value that needs shifting
4383 up to the msb. eg. a QImode value and we're padding
4384 upward on a BYTES_BIG_ENDIAN machine. */
4385 if (size < UNITS_PER_WORD
4386 && (argvec[argnum].locate.where_pad
4387 == (BYTES_BIG_ENDIAN ? upward : downward)))
4389 rtx x;
4390 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4392 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4393 report the whole reg as used. Strictly speaking, the
4394 call only uses SIZE bytes at the msb end, but it doesn't
4395 seem worth generating rtl to say that. */
4396 reg = gen_rtx_REG (word_mode, REGNO (reg));
4397 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4398 if (x != reg)
4399 emit_move_insn (reg, x);
4401 #endif
4404 NO_DEFER_POP;
4407 /* Any regs containing parms remain in use through the call. */
4408 for (count = 0; count < nargs; count++)
4410 rtx reg = argvec[count].reg;
4411 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4412 use_group_regs (&call_fusage, reg);
4413 else if (reg != 0)
4415 int partial = argvec[count].partial;
4416 if (partial)
4418 int nregs;
4419 gcc_assert (partial % UNITS_PER_WORD == 0);
4420 nregs = partial / UNITS_PER_WORD;
4421 use_regs (&call_fusage, REGNO (reg), nregs);
4423 else
4424 use_reg (&call_fusage, reg);
4428 /* Pass the function the address in which to return a structure value. */
4429 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4431 emit_move_insn (struct_value,
4432 force_reg (Pmode,
4433 force_operand (XEXP (mem_value, 0),
4434 NULL_RTX)));
4435 if (REG_P (struct_value))
4436 use_reg (&call_fusage, struct_value);
4439 /* Don't allow popping to be deferred, since then
4440 cse'ing of library calls could delete a call and leave the pop. */
4441 NO_DEFER_POP;
4442 valreg = (mem_value == 0 && outmode != VOIDmode
4443 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4445 /* Stack must be properly aligned now. */
4446 gcc_assert (!(stack_pointer_delta
4447 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4449 before_call = get_last_insn ();
4451 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4452 will set inhibit_defer_pop to that value. */
4453 /* The return type is needed to decide how many bytes the function pops.
4454 Signedness plays no role in that, so for simplicity, we pretend it's
4455 always signed. We also assume that the list of arguments passed has
4456 no impact, so we pretend it is unknown. */
4458 emit_call_1 (fun, NULL,
4459 get_identifier (XSTR (orgfun, 0)),
4460 build_function_type (tfom, NULL_TREE),
4461 original_args_size.constant, args_size.constant,
4462 struct_value_size,
4463 targetm.calls.function_arg (args_so_far,
4464 VOIDmode, void_type_node, true),
4465 valreg,
4466 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4468 if (flag_ipa_ra)
4470 rtx datum = orgfun;
4471 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4472 rtx_call_insn *last = last_call_insn ();
4473 add_reg_note (last, REG_CALL_DECL, datum);
4476 /* Right-shift returned value if necessary. */
4477 if (!pcc_struct_value
4478 && TYPE_MODE (tfom) != BLKmode
4479 && targetm.calls.return_in_msb (tfom))
4481 shift_return_value (TYPE_MODE (tfom), false, valreg);
4482 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4485 targetm.calls.end_call_args ();
4487 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4488 that it should complain if nonvolatile values are live. For
4489 functions that cannot return, inform flow that control does not
4490 fall through. */
4491 if (flags & ECF_NORETURN)
4493 /* The barrier note must be emitted
4494 immediately after the CALL_INSN. Some ports emit more than
4495 just a CALL_INSN above, so we must search for it here. */
4496 rtx_insn *last = get_last_insn ();
4497 while (!CALL_P (last))
4499 last = PREV_INSN (last);
4500 /* There was no CALL_INSN? */
4501 gcc_assert (last != before_call);
4504 emit_barrier_after (last);
4507 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
4508 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
4509 if (flags & ECF_NOTHROW)
4511 rtx_insn *last = get_last_insn ();
4512 while (!CALL_P (last))
4514 last = PREV_INSN (last);
4515 /* There was no CALL_INSN? */
4516 gcc_assert (last != before_call);
4519 make_reg_eh_region_note_nothrow_nononlocal (last);
4522 /* Now restore inhibit_defer_pop to its actual original value. */
4523 OK_DEFER_POP;
4525 pop_temp_slots ();
4527 /* Copy the value to the right place. */
4528 if (outmode != VOIDmode && retval)
4530 if (mem_value)
4532 if (value == 0)
4533 value = mem_value;
4534 if (value != mem_value)
4535 emit_move_insn (value, mem_value);
4537 else if (GET_CODE (valreg) == PARALLEL)
4539 if (value == 0)
4540 value = gen_reg_rtx (outmode);
4541 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4543 else
4545 /* Convert to the proper mode if a promotion has been active. */
4546 if (GET_MODE (valreg) != outmode)
4548 int unsignedp = TYPE_UNSIGNED (tfom);
4550 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4551 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4552 == GET_MODE (valreg));
4553 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4556 if (value != 0)
4557 emit_move_insn (value, valreg);
4558 else
4559 value = valreg;
4563 if (ACCUMULATE_OUTGOING_ARGS)
4565 #ifdef REG_PARM_STACK_SPACE
4566 if (save_area)
4567 restore_fixed_argument_area (save_area, argblock,
4568 high_to_save, low_to_save);
4569 #endif
4571 /* If we saved any argument areas, restore them. */
4572 for (count = 0; count < nargs; count++)
4573 if (argvec[count].save_area)
4575 machine_mode save_mode = GET_MODE (argvec[count].save_area);
4576 rtx adr = plus_constant (Pmode, argblock,
4577 argvec[count].locate.offset.constant);
4578 rtx stack_area = gen_rtx_MEM (save_mode,
4579 memory_address (save_mode, adr));
4581 if (save_mode == BLKmode)
4582 emit_block_move (stack_area,
4583 validize_mem
4584 (copy_rtx (argvec[count].save_area)),
4585 GEN_INT (argvec[count].locate.size.constant),
4586 BLOCK_OP_CALL_PARM);
4587 else
4588 emit_move_insn (stack_area, argvec[count].save_area);
4591 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4592 stack_usage_map = initial_stack_usage_map;
4595 free (stack_usage_map_buf);
4597 return value;
4601 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4602 (emitting the queue unless NO_QUEUE is nonzero),
4603 for a value of mode OUTMODE,
4604 with NARGS different arguments, passed as alternating rtx values
4605 and machine_modes to convert them to.
4607 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4608 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4609 other types of library calls. */
4611 void
4612 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4613 machine_mode outmode, int nargs, ...)
4615 va_list p;
4617 va_start (p, nargs);
4618 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4619 va_end (p);
4622 /* Like emit_library_call except that an extra argument, VALUE,
4623 comes second and says where to store the result.
4624 (If VALUE is zero, this function chooses a convenient way
4625 to return the value.
4627 This function returns an rtx for where the value is to be found.
4628 If VALUE is nonzero, VALUE is returned. */
4631 emit_library_call_value (rtx orgfun, rtx value,
4632 enum libcall_type fn_type,
4633 machine_mode outmode, int nargs, ...)
4635 rtx result;
4636 va_list p;
4638 va_start (p, nargs);
4639 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4640 nargs, p);
4641 va_end (p);
4643 return result;
4647 /* Store pointer bounds argument ARG into Bounds Table entry
4648 associated with PARM. */
4649 static void
4650 store_bounds (struct arg_data *arg, struct arg_data *parm)
4652 rtx slot = NULL, ptr = NULL, addr = NULL;
4654 /* We may pass bounds not associated with any pointer. */
4655 if (!parm)
4657 gcc_assert (arg->special_slot);
4658 slot = arg->special_slot;
4659 ptr = const0_rtx;
4661 /* Find pointer associated with bounds and where it is
4662 passed. */
4663 else
4665 if (!parm->reg)
4667 gcc_assert (!arg->special_slot);
4669 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
4671 else if (REG_P (parm->reg))
4673 gcc_assert (arg->special_slot);
4674 slot = arg->special_slot;
4676 if (MEM_P (parm->value))
4677 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
4678 else if (REG_P (parm->value))
4679 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
4680 else
4682 gcc_assert (!arg->pointer_offset);
4683 ptr = parm->value;
4686 else
4688 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
4690 gcc_assert (arg->special_slot);
4691 slot = arg->special_slot;
4693 if (parm->parallel_value)
4694 ptr = chkp_get_value_with_offs (parm->parallel_value,
4695 GEN_INT (arg->pointer_offset));
4696 else
4697 gcc_unreachable ();
4701 /* Expand bounds. */
4702 if (!arg->value)
4703 arg->value = expand_normal (arg->tree_value);
4705 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
4708 /* Store a single argument for a function call
4709 into the register or memory area where it must be passed.
4710 *ARG describes the argument value and where to pass it.
4712 ARGBLOCK is the address of the stack-block for all the arguments,
4713 or 0 on a machine where arguments are pushed individually.
4715 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4716 so must be careful about how the stack is used.
4718 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4719 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4720 that we need not worry about saving and restoring the stack.
4722 FNDECL is the declaration of the function we are calling.
4724 Return nonzero if this arg should cause sibcall failure,
4725 zero otherwise. */
4727 static int
4728 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4729 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4731 tree pval = arg->tree_value;
4732 rtx reg = 0;
4733 int partial = 0;
4734 int used = 0;
4735 int i, lower_bound = 0, upper_bound = 0;
4736 int sibcall_failure = 0;
4738 if (TREE_CODE (pval) == ERROR_MARK)
4739 return 1;
4741 /* Push a new temporary level for any temporaries we make for
4742 this argument. */
4743 push_temp_slots ();
4745 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4747 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4748 save any previous data at that location. */
4749 if (argblock && ! variable_size && arg->stack)
4751 if (ARGS_GROW_DOWNWARD)
4753 /* stack_slot is negative, but we want to index stack_usage_map
4754 with positive values. */
4755 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4756 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4757 else
4758 upper_bound = 0;
4760 lower_bound = upper_bound - arg->locate.size.constant;
4762 else
4764 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4765 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4766 else
4767 lower_bound = 0;
4769 upper_bound = lower_bound + arg->locate.size.constant;
4772 i = lower_bound;
4773 /* Don't worry about things in the fixed argument area;
4774 it has already been saved. */
4775 if (i < reg_parm_stack_space)
4776 i = reg_parm_stack_space;
4777 while (i < upper_bound && stack_usage_map[i] == 0)
4778 i++;
4780 if (i < upper_bound)
4782 /* We need to make a save area. */
4783 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4784 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4785 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4786 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4788 if (save_mode == BLKmode)
4790 arg->save_area
4791 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
4792 preserve_temp_slots (arg->save_area);
4793 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
4794 stack_area,
4795 GEN_INT (arg->locate.size.constant),
4796 BLOCK_OP_CALL_PARM);
4798 else
4800 arg->save_area = gen_reg_rtx (save_mode);
4801 emit_move_insn (arg->save_area, stack_area);
4807 /* If this isn't going to be placed on both the stack and in registers,
4808 set up the register and number of words. */
4809 if (! arg->pass_on_stack)
4811 if (flags & ECF_SIBCALL)
4812 reg = arg->tail_call_reg;
4813 else
4814 reg = arg->reg;
4815 partial = arg->partial;
4818 /* Being passed entirely in a register. We shouldn't be called in
4819 this case. */
4820 gcc_assert (reg == 0 || partial != 0);
4822 /* If this arg needs special alignment, don't load the registers
4823 here. */
4824 if (arg->n_aligned_regs != 0)
4825 reg = 0;
4827 /* If this is being passed partially in a register, we can't evaluate
4828 it directly into its stack slot. Otherwise, we can. */
4829 if (arg->value == 0)
4831 /* stack_arg_under_construction is nonzero if a function argument is
4832 being evaluated directly into the outgoing argument list and
4833 expand_call must take special action to preserve the argument list
4834 if it is called recursively.
4836 For scalar function arguments stack_usage_map is sufficient to
4837 determine which stack slots must be saved and restored. Scalar
4838 arguments in general have pass_on_stack == 0.
4840 If this argument is initialized by a function which takes the
4841 address of the argument (a C++ constructor or a C function
4842 returning a BLKmode structure), then stack_usage_map is
4843 insufficient and expand_call must push the stack around the
4844 function call. Such arguments have pass_on_stack == 1.
4846 Note that it is always safe to set stack_arg_under_construction,
4847 but this generates suboptimal code if set when not needed. */
4849 if (arg->pass_on_stack)
4850 stack_arg_under_construction++;
4852 arg->value = expand_expr (pval,
4853 (partial
4854 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4855 ? NULL_RTX : arg->stack,
4856 VOIDmode, EXPAND_STACK_PARM);
4858 /* If we are promoting object (or for any other reason) the mode
4859 doesn't agree, convert the mode. */
4861 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4862 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4863 arg->value, arg->unsignedp);
4865 if (arg->pass_on_stack)
4866 stack_arg_under_construction--;
4869 /* Check for overlap with already clobbered argument area. */
4870 if ((flags & ECF_SIBCALL)
4871 && MEM_P (arg->value)
4872 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4873 arg->locate.size.constant))
4874 sibcall_failure = 1;
4876 /* Don't allow anything left on stack from computation
4877 of argument to alloca. */
4878 if (flags & ECF_MAY_BE_ALLOCA)
4879 do_pending_stack_adjust ();
4881 if (arg->value == arg->stack)
4882 /* If the value is already in the stack slot, we are done. */
4884 else if (arg->mode != BLKmode)
4886 int size;
4887 unsigned int parm_align;
4889 /* Argument is a scalar, not entirely passed in registers.
4890 (If part is passed in registers, arg->partial says how much
4891 and emit_push_insn will take care of putting it there.)
4893 Push it, and if its size is less than the
4894 amount of space allocated to it,
4895 also bump stack pointer by the additional space.
4896 Note that in C the default argument promotions
4897 will prevent such mismatches. */
4899 size = GET_MODE_SIZE (arg->mode);
4900 /* Compute how much space the push instruction will push.
4901 On many machines, pushing a byte will advance the stack
4902 pointer by a halfword. */
4903 #ifdef PUSH_ROUNDING
4904 size = PUSH_ROUNDING (size);
4905 #endif
4906 used = size;
4908 /* Compute how much space the argument should get:
4909 round up to a multiple of the alignment for arguments. */
4910 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4911 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4912 / (PARM_BOUNDARY / BITS_PER_UNIT))
4913 * (PARM_BOUNDARY / BITS_PER_UNIT));
4915 /* Compute the alignment of the pushed argument. */
4916 parm_align = arg->locate.boundary;
4917 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4919 int pad = used - size;
4920 if (pad)
4922 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4923 parm_align = MIN (parm_align, pad_align);
4927 /* This isn't already where we want it on the stack, so put it there.
4928 This can either be done with push or copy insns. */
4929 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4930 parm_align, partial, reg, used - size, argblock,
4931 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4932 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
4933 sibcall_failure = 1;
4935 /* Unless this is a partially-in-register argument, the argument is now
4936 in the stack. */
4937 if (partial == 0)
4938 arg->value = arg->stack;
4940 else
4942 /* BLKmode, at least partly to be pushed. */
4944 unsigned int parm_align;
4945 int excess;
4946 rtx size_rtx;
4948 /* Pushing a nonscalar.
4949 If part is passed in registers, PARTIAL says how much
4950 and emit_push_insn will take care of putting it there. */
4952 /* Round its size up to a multiple
4953 of the allocation unit for arguments. */
4955 if (arg->locate.size.var != 0)
4957 excess = 0;
4958 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4960 else
4962 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4963 for BLKmode is careful to avoid it. */
4964 excess = (arg->locate.size.constant
4965 - int_size_in_bytes (TREE_TYPE (pval))
4966 + partial);
4967 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4968 NULL_RTX, TYPE_MODE (sizetype),
4969 EXPAND_NORMAL);
4972 parm_align = arg->locate.boundary;
4974 /* When an argument is padded down, the block is aligned to
4975 PARM_BOUNDARY, but the actual argument isn't. */
4976 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4978 if (arg->locate.size.var)
4979 parm_align = BITS_PER_UNIT;
4980 else if (excess)
4982 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4983 parm_align = MIN (parm_align, excess_align);
4987 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4989 /* emit_push_insn might not work properly if arg->value and
4990 argblock + arg->locate.offset areas overlap. */
4991 rtx x = arg->value;
4992 int i = 0;
4994 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4995 || (GET_CODE (XEXP (x, 0)) == PLUS
4996 && XEXP (XEXP (x, 0), 0) ==
4997 crtl->args.internal_arg_pointer
4998 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5000 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5001 i = INTVAL (XEXP (XEXP (x, 0), 1));
5003 /* expand_call should ensure this. */
5004 gcc_assert (!arg->locate.offset.var
5005 && arg->locate.size.var == 0
5006 && CONST_INT_P (size_rtx));
5008 if (arg->locate.offset.constant > i)
5010 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
5011 sibcall_failure = 1;
5013 else if (arg->locate.offset.constant < i)
5015 /* Use arg->locate.size.constant instead of size_rtx
5016 because we only care about the part of the argument
5017 on the stack. */
5018 if (i < (arg->locate.offset.constant
5019 + arg->locate.size.constant))
5020 sibcall_failure = 1;
5022 else
5024 /* Even though they appear to be at the same location,
5025 if part of the outgoing argument is in registers,
5026 they aren't really at the same location. Check for
5027 this by making sure that the incoming size is the
5028 same as the outgoing size. */
5029 if (arg->locate.size.constant != INTVAL (size_rtx))
5030 sibcall_failure = 1;
5035 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5036 parm_align, partial, reg, excess, argblock,
5037 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5038 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5040 /* Unless this is a partially-in-register argument, the argument is now
5041 in the stack.
5043 ??? Unlike the case above, in which we want the actual
5044 address of the data, so that we can load it directly into a
5045 register, here we want the address of the stack slot, so that
5046 it's properly aligned for word-by-word copying or something
5047 like that. It's not clear that this is always correct. */
5048 if (partial == 0)
5049 arg->value = arg->stack_slot;
5052 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5054 tree type = TREE_TYPE (arg->tree_value);
5055 arg->parallel_value
5056 = emit_group_load_into_temps (arg->reg, arg->value, type,
5057 int_size_in_bytes (type));
5060 /* Mark all slots this store used. */
5061 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5062 && argblock && ! variable_size && arg->stack)
5063 for (i = lower_bound; i < upper_bound; i++)
5064 stack_usage_map[i] = 1;
5066 /* Once we have pushed something, pops can't safely
5067 be deferred during the rest of the arguments. */
5068 NO_DEFER_POP;
5070 /* Free any temporary slots made in processing this argument. */
5071 pop_temp_slots ();
5073 return sibcall_failure;
5076 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5078 bool
5079 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5080 const_tree type)
5082 if (!type)
5083 return false;
5085 /* If the type has variable size... */
5086 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5087 return true;
5089 /* If the type is marked as addressable (it is required
5090 to be constructed into the stack)... */
5091 if (TREE_ADDRESSABLE (type))
5092 return true;
5094 return false;
5097 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5098 takes trailing padding of a structure into account. */
5099 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5101 bool
5102 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5104 if (!type)
5105 return false;
5107 /* If the type has variable size... */
5108 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5109 return true;
5111 /* If the type is marked as addressable (it is required
5112 to be constructed into the stack)... */
5113 if (TREE_ADDRESSABLE (type))
5114 return true;
5116 /* If the padding and mode of the type is such that a copy into
5117 a register would put it into the wrong part of the register. */
5118 if (mode == BLKmode
5119 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5120 && (FUNCTION_ARG_PADDING (mode, type)
5121 == (BYTES_BIG_ENDIAN ? upward : downward)))
5122 return true;
5124 return false;