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1.1 root 1: /* Convert function calls to rtl insns, for GNU C compiler.
2: Copyright (C) 1989, 1992, 1993 Free Software Foundation, Inc.
3:
4: This file is part of GNU CC.
5:
6: GNU CC is free software; you can redistribute it and/or modify
7: it under the terms of the GNU General Public License as published by
8: the Free Software Foundation; either version 2, or (at your option)
9: any later version.
10:
11: GNU CC is distributed in the hope that it will be useful,
12: but WITHOUT ANY WARRANTY; without even the implied warranty of
13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14: GNU General Public License for more details.
15:
16: You should have received a copy of the GNU General Public License
17: along with GNU CC; see the file COPYING. If not, write to
18: the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
19:
20: #include "config.h"
21: #include "rtl.h"
22: #include "tree.h"
23: #include "flags.h"
24: #include "expr.h"
25: #include "gvarargs.h"
26: #include "insn-flags.h"
27:
28: /* Decide whether a function's arguments should be processed
29: from first to last or from last to first.
30:
31: They should if the stack and args grow in opposite directions, but
32: only if we have push insns. */
33:
34: #ifdef PUSH_ROUNDING
35:
36: #if defined (STACK_GROWS_DOWNWARD) != defined (ARGS_GROW_DOWNWARD)
37: #define PUSH_ARGS_REVERSED /* If it's last to first */
38: #endif
39:
40: #endif
41:
42: /* Like STACK_BOUNDARY but in units of bytes, not bits. */
43: #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
44:
45: /* Data structure and subroutines used within expand_call. */
46:
47: struct arg_data
48: {
49: /* Tree node for this argument. */
50: tree tree_value;
51: /* Mode for value; TYPE_MODE unless promoted. */
52: enum machine_mode mode;
53: /* Current RTL value for argument, or 0 if it isn't precomputed. */
54: rtx value;
55: /* Initially-compute RTL value for argument; only for const functions. */
56: rtx initial_value;
57: /* Register to pass this argument in, 0 if passed on stack, or an
58: EXPR_LIST if the arg is to be copied into multiple different
59: registers. */
60: rtx reg;
61: /* If REG was promoted from the actual mode of the argument expression,
62: indicates whether the promotion is sign- or zero-extended. */
63: int unsignedp;
64: /* Number of registers to use. 0 means put the whole arg in registers.
65: Also 0 if not passed in registers. */
66: int partial;
67: /* Non-zero if argument must be passed on stack.
68: Note that some arguments may be passed on the stack
69: even though pass_on_stack is zero, just because FUNCTION_ARG says so.
70: pass_on_stack identifies arguments that *cannot* go in registers. */
71: int pass_on_stack;
72: /* Offset of this argument from beginning of stack-args. */
73: struct args_size offset;
74: /* Similar, but offset to the start of the stack slot. Different from
75: OFFSET if this arg pads downward. */
76: struct args_size slot_offset;
77: /* Size of this argument on the stack, rounded up for any padding it gets,
78: parts of the argument passed in registers do not count.
79: If REG_PARM_STACK_SPACE is defined, then register parms
80: are counted here as well. */
81: struct args_size size;
82: /* Location on the stack at which parameter should be stored. The store
83: has already been done if STACK == VALUE. */
84: rtx stack;
85: /* Location on the stack of the start of this argument slot. This can
86: differ from STACK if this arg pads downward. This location is known
87: to be aligned to FUNCTION_ARG_BOUNDARY. */
88: rtx stack_slot;
89: #ifdef ACCUMULATE_OUTGOING_ARGS
90: /* Place that this stack area has been saved, if needed. */
91: rtx save_area;
92: #endif
93: #ifdef STRICT_ALIGNMENT
94: /* If an argument's alignment does not permit direct copying into registers,
95: copy in smaller-sized pieces into pseudos. These are stored in a
96: block pointed to by this field. The next field says how many
97: word-sized pseudos we made. */
98: rtx *aligned_regs;
99: int n_aligned_regs;
100: #endif
101: };
102:
103: #ifdef ACCUMULATE_OUTGOING_ARGS
104: /* A vector of one char per byte of stack space. A byte if non-zero if
105: the corresponding stack location has been used.
106: This vector is used to prevent a function call within an argument from
107: clobbering any stack already set up. */
108: static char *stack_usage_map;
109:
110: /* Size of STACK_USAGE_MAP. */
111: static int highest_outgoing_arg_in_use;
112:
113: /* stack_arg_under_construction is nonzero when an argument may be
114: initialized with a constructor call (including a C function that
115: returns a BLKmode struct) and expand_call must take special action
116: to make sure the object being constructed does not overlap the
117: argument list for the constructor call. */
118: int stack_arg_under_construction;
119: #endif
120:
121: static int calls_function PROTO((tree, int));
122: static int calls_function_1 PROTO((tree, int));
123: static void emit_call_1 PROTO((rtx, tree, int, int, rtx, rtx, int,
124: rtx, int));
125: static void store_one_arg PROTO ((struct arg_data *, rtx, int, int,
126: tree, int));
127:
128: /* If WHICH is 1, return 1 if EXP contains a call to the built-in function
129: `alloca'.
130:
131: If WHICH is 0, return 1 if EXP contains a call to any function.
132: Actually, we only need return 1 if evaluating EXP would require pushing
133: arguments on the stack, but that is too difficult to compute, so we just
134: assume any function call might require the stack. */
135:
136: static tree calls_function_save_exprs;
137:
138: static int
139: calls_function (exp, which)
140: tree exp;
141: int which;
142: {
143: int val;
144: calls_function_save_exprs = 0;
145: val = calls_function_1 (exp, which);
146: calls_function_save_exprs = 0;
147: return val;
148: }
149:
150: static int
151: calls_function_1 (exp, which)
152: tree exp;
153: int which;
154: {
155: register int i;
156: int type = TREE_CODE_CLASS (TREE_CODE (exp));
157: int length = tree_code_length[(int) TREE_CODE (exp)];
158:
159: /* Only expressions and references can contain calls. */
160:
161: if (type != 'e' && type != '<' && type != '1' && type != '2' && type != 'r'
162: && type != 'b')
163: return 0;
164:
165: switch (TREE_CODE (exp))
166: {
167: case CALL_EXPR:
168: if (which == 0)
169: return 1;
170: else if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
171: && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
172: == FUNCTION_DECL)
173: && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
174: && (DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
175: == BUILT_IN_ALLOCA))
176: return 1;
177:
178: /* Third operand is RTL. */
179: length = 2;
180: break;
181:
182: case SAVE_EXPR:
183: if (SAVE_EXPR_RTL (exp) != 0)
184: return 0;
185: if (value_member (exp, calls_function_save_exprs))
186: return 0;
187: calls_function_save_exprs = tree_cons (NULL_TREE, exp,
188: calls_function_save_exprs);
189: return (TREE_OPERAND (exp, 0) != 0
190: && calls_function_1 (TREE_OPERAND (exp, 0), which));
191:
192: case BLOCK:
193: {
194: register tree local;
195:
196: for (local = BLOCK_VARS (exp); local; local = TREE_CHAIN (local))
197: if (DECL_INITIAL (local) != 0
198: && calls_function_1 (DECL_INITIAL (local), which))
199: return 1;
200: }
201: {
202: register tree subblock;
203:
204: for (subblock = BLOCK_SUBBLOCKS (exp);
205: subblock;
206: subblock = TREE_CHAIN (subblock))
207: if (calls_function_1 (subblock, which))
208: return 1;
209: }
210: return 0;
211:
212: case METHOD_CALL_EXPR:
213: length = 3;
214: break;
215:
216: case WITH_CLEANUP_EXPR:
217: length = 1;
218: break;
219:
220: case RTL_EXPR:
221: return 0;
222: }
223:
224: for (i = 0; i < length; i++)
225: if (TREE_OPERAND (exp, i) != 0
226: && calls_function_1 (TREE_OPERAND (exp, i), which))
227: return 1;
228:
229: return 0;
230: }
231:
232: /* Force FUNEXP into a form suitable for the address of a CALL,
233: and return that as an rtx. Also load the static chain register
234: if FNDECL is a nested function.
235:
236: USE_INSNS points to a variable holding a chain of USE insns
237: to which a USE of the static chain
238: register should be added, if required. */
239:
240: rtx
241: prepare_call_address (funexp, fndecl, use_insns)
242: rtx funexp;
243: tree fndecl;
244: rtx *use_insns;
245: {
246: rtx static_chain_value = 0;
247:
248: funexp = protect_from_queue (funexp, 0);
249:
250: if (fndecl != 0)
251: /* Get possible static chain value for nested function in C. */
252: static_chain_value = lookup_static_chain (fndecl);
253:
254: /* Make a valid memory address and copy constants thru pseudo-regs,
255: but not for a constant address if -fno-function-cse. */
256: if (GET_CODE (funexp) != SYMBOL_REF)
257: funexp = memory_address (FUNCTION_MODE, funexp);
258: else
259: {
260: #ifndef NO_FUNCTION_CSE
261: if (optimize && ! flag_no_function_cse)
262: #ifdef NO_RECURSIVE_FUNCTION_CSE
263: if (fndecl != current_function_decl)
264: #endif
265: funexp = force_reg (Pmode, funexp);
266: #endif
267: }
268:
269: if (static_chain_value != 0)
270: {
271: emit_move_insn (static_chain_rtx, static_chain_value);
272:
273: /* Put the USE insn in the chain we were passed. It will later be
274: output immediately in front of the CALL insn. */
275: push_to_sequence (*use_insns);
276: emit_insn (gen_rtx (USE, VOIDmode, static_chain_rtx));
277: *use_insns = get_insns ();
278: end_sequence ();
279: }
280:
281: return funexp;
282: }
283:
284: /* Generate instructions to call function FUNEXP,
285: and optionally pop the results.
286: The CALL_INSN is the first insn generated.
287:
288: FUNTYPE is the data type of the function, or, for a library call,
289: the identifier for the name of the call. This is given to the
290: macro RETURN_POPS_ARGS to determine whether this function pops its own args.
291:
292: STACK_SIZE is the number of bytes of arguments on the stack,
293: rounded up to STACK_BOUNDARY; zero if the size is variable.
294: This is both to put into the call insn and
295: to generate explicit popping code if necessary.
296:
297: STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
298: It is zero if this call doesn't want a structure value.
299:
300: NEXT_ARG_REG is the rtx that results from executing
301: FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1)
302: just after all the args have had their registers assigned.
303: This could be whatever you like, but normally it is the first
304: arg-register beyond those used for args in this call,
305: or 0 if all the arg-registers are used in this call.
306: It is passed on to `gen_call' so you can put this info in the call insn.
307:
308: VALREG is a hard register in which a value is returned,
309: or 0 if the call does not return a value.
310:
311: OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
312: the args to this call were processed.
313: We restore `inhibit_defer_pop' to that value.
314:
315: USE_INSNS is a chain of USE insns to be emitted immediately before
316: the actual CALL insn.
317:
318: IS_CONST is true if this is a `const' call. */
319:
320: static void
321: emit_call_1 (funexp, funtype, stack_size, struct_value_size, next_arg_reg,
322: valreg, old_inhibit_defer_pop, use_insns, is_const)
323: rtx funexp;
324: tree funtype;
325: int stack_size;
326: int struct_value_size;
327: rtx next_arg_reg;
328: rtx valreg;
329: int old_inhibit_defer_pop;
330: rtx use_insns;
331: int is_const;
332: {
333: rtx stack_size_rtx = GEN_INT (stack_size);
334: rtx struct_value_size_rtx = GEN_INT (struct_value_size);
335: rtx call_insn;
336: int already_popped = 0;
337:
338: /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
339: and we don't want to load it into a register as an optimization,
340: because prepare_call_address already did it if it should be done. */
341: if (GET_CODE (funexp) != SYMBOL_REF)
342: funexp = memory_address (FUNCTION_MODE, funexp);
343:
344: #ifndef ACCUMULATE_OUTGOING_ARGS
345: #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
346: if (HAVE_call_pop && HAVE_call_value_pop
347: && (RETURN_POPS_ARGS (funtype, stack_size) > 0 || stack_size == 0))
348: {
349: rtx n_pop = GEN_INT (RETURN_POPS_ARGS (funtype, stack_size));
350: rtx pat;
351:
352: /* If this subroutine pops its own args, record that in the call insn
353: if possible, for the sake of frame pointer elimination. */
354: if (valreg)
355: pat = gen_call_value_pop (valreg,
356: gen_rtx (MEM, FUNCTION_MODE, funexp),
357: stack_size_rtx, next_arg_reg, n_pop);
358: else
359: pat = gen_call_pop (gen_rtx (MEM, FUNCTION_MODE, funexp),
360: stack_size_rtx, next_arg_reg, n_pop);
361:
362: emit_call_insn (pat);
363: already_popped = 1;
364: }
365: else
366: #endif
367: #endif
368:
369: #if defined (HAVE_call) && defined (HAVE_call_value)
370: if (HAVE_call && HAVE_call_value)
371: {
372: if (valreg)
373: emit_call_insn (gen_call_value (valreg,
374: gen_rtx (MEM, FUNCTION_MODE, funexp),
375: stack_size_rtx, next_arg_reg,
376: NULL_RTX));
377: else
378: emit_call_insn (gen_call (gen_rtx (MEM, FUNCTION_MODE, funexp),
379: stack_size_rtx, next_arg_reg,
380: struct_value_size_rtx));
381: }
382: else
383: #endif
384: abort ();
385:
386: /* Find the CALL insn we just emitted and write the USE insns before it. */
387: for (call_insn = get_last_insn ();
388: call_insn && GET_CODE (call_insn) != CALL_INSN;
389: call_insn = PREV_INSN (call_insn))
390: ;
391:
392: if (! call_insn)
393: abort ();
394:
395: /* Put the USE insns before the CALL. */
396: emit_insns_before (use_insns, call_insn);
397:
398: /* If this is a const call, then set the insn's unchanging bit. */
399: if (is_const)
400: CONST_CALL_P (call_insn) = 1;
401:
402: /* Restore this now, so that we do defer pops for this call's args
403: if the context of the call as a whole permits. */
404: inhibit_defer_pop = old_inhibit_defer_pop;
405:
406: #ifndef ACCUMULATE_OUTGOING_ARGS
407: /* If returning from the subroutine does not automatically pop the args,
408: we need an instruction to pop them sooner or later.
409: Perhaps do it now; perhaps just record how much space to pop later.
410:
411: If returning from the subroutine does pop the args, indicate that the
412: stack pointer will be changed. */
413:
414: if (stack_size != 0 && RETURN_POPS_ARGS (funtype, stack_size) > 0)
415: {
416: if (!already_popped)
417: emit_insn (gen_rtx (CLOBBER, VOIDmode, stack_pointer_rtx));
418: stack_size -= RETURN_POPS_ARGS (funtype, stack_size);
419: stack_size_rtx = GEN_INT (stack_size);
420: }
421:
422: if (stack_size != 0)
423: {
424: if (flag_defer_pop && inhibit_defer_pop == 0 && !is_const)
425: pending_stack_adjust += stack_size;
426: else
427: adjust_stack (stack_size_rtx);
428: }
429: #endif
430: }
431:
432: /* Generate all the code for a function call
433: and return an rtx for its value.
434: Store the value in TARGET (specified as an rtx) if convenient.
435: If the value is stored in TARGET then TARGET is returned.
436: If IGNORE is nonzero, then we ignore the value of the function call. */
437:
438: rtx
439: expand_call (exp, target, ignore)
440: tree exp;
441: rtx target;
442: int ignore;
443: {
444: /* List of actual parameters. */
445: tree actparms = TREE_OPERAND (exp, 1);
446: /* RTX for the function to be called. */
447: rtx funexp;
448: /* Tree node for the function to be called (not the address!). */
449: tree funtree;
450: /* Data type of the function. */
451: tree funtype;
452: /* Declaration of the function being called,
453: or 0 if the function is computed (not known by name). */
454: tree fndecl = 0;
455: char *name = 0;
456:
457: /* Register in which non-BLKmode value will be returned,
458: or 0 if no value or if value is BLKmode. */
459: rtx valreg;
460: /* Address where we should return a BLKmode value;
461: 0 if value not BLKmode. */
462: rtx structure_value_addr = 0;
463: /* Nonzero if that address is being passed by treating it as
464: an extra, implicit first parameter. Otherwise,
465: it is passed by being copied directly into struct_value_rtx. */
466: int structure_value_addr_parm = 0;
467: /* Size of aggregate value wanted, or zero if none wanted
468: or if we are using the non-reentrant PCC calling convention
469: or expecting the value in registers. */
470: int struct_value_size = 0;
471: /* Nonzero if called function returns an aggregate in memory PCC style,
472: by returning the address of where to find it. */
473: int pcc_struct_value = 0;
474:
475: /* Number of actual parameters in this call, including struct value addr. */
476: int num_actuals;
477: /* Number of named args. Args after this are anonymous ones
478: and they must all go on the stack. */
479: int n_named_args;
480: /* Count arg position in order args appear. */
481: int argpos;
482:
483: /* Vector of information about each argument.
484: Arguments are numbered in the order they will be pushed,
485: not the order they are written. */
486: struct arg_data *args;
487:
488: /* Total size in bytes of all the stack-parms scanned so far. */
489: struct args_size args_size;
490: /* Size of arguments before any adjustments (such as rounding). */
491: struct args_size original_args_size;
492: /* Data on reg parms scanned so far. */
493: CUMULATIVE_ARGS args_so_far;
494: /* Nonzero if a reg parm has been scanned. */
495: int reg_parm_seen;
496: /* Nonzero if this is an indirect function call. */
497: int current_call_is_indirect = 0;
498:
499: /* Nonzero if we must avoid push-insns in the args for this call.
500: If stack space is allocated for register parameters, but not by the
501: caller, then it is preallocated in the fixed part of the stack frame.
502: So the entire argument block must then be preallocated (i.e., we
503: ignore PUSH_ROUNDING in that case). */
504:
505: #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
506: int must_preallocate = 1;
507: #else
508: #ifdef PUSH_ROUNDING
509: int must_preallocate = 0;
510: #else
511: int must_preallocate = 1;
512: #endif
513: #endif
514:
515: /* Size of the stack reserved for parameter registers. */
516: int reg_parm_stack_space = 0;
517:
518: /* 1 if scanning parms front to back, -1 if scanning back to front. */
519: int inc;
520: /* Address of space preallocated for stack parms
521: (on machines that lack push insns), or 0 if space not preallocated. */
522: rtx argblock = 0;
523:
524: /* Nonzero if it is plausible that this is a call to alloca. */
525: int may_be_alloca;
526: /* Nonzero if this is a call to setjmp or a related function. */
527: int returns_twice;
528: /* Nonzero if this is a call to `longjmp'. */
529: int is_longjmp;
530: /* Nonzero if this is a call to an inline function. */
531: int is_integrable = 0;
532: /* Nonzero if this is a call to a `const' function.
533: Note that only explicitly named functions are handled as `const' here. */
534: int is_const = 0;
535: /* Nonzero if this is a call to a `volatile' function. */
536: int is_volatile = 0;
537: #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
538: /* Define the boundary of the register parm stack space that needs to be
539: save, if any. */
540: int low_to_save = -1, high_to_save;
541: rtx save_area = 0; /* Place that it is saved */
542: #endif
543:
544: #ifdef ACCUMULATE_OUTGOING_ARGS
545: int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
546: char *initial_stack_usage_map = stack_usage_map;
547: #endif
548:
549: rtx old_stack_level = 0;
550: int old_pending_adj;
551: int old_stack_arg_under_construction;
552: int old_inhibit_defer_pop = inhibit_defer_pop;
553: tree old_cleanups = cleanups_this_call;
554:
555: rtx use_insns = 0;
556:
557: register tree p;
558: register int i, j;
559:
560: /* See if we can find a DECL-node for the actual function.
561: As a result, decide whether this is a call to an integrable function. */
562:
563: p = TREE_OPERAND (exp, 0);
564: if (TREE_CODE (p) == ADDR_EXPR)
565: {
566: fndecl = TREE_OPERAND (p, 0);
567: if (TREE_CODE (fndecl) != FUNCTION_DECL)
568: {
569: /* May still be a `const' function if it is
570: a call through a pointer-to-const.
571: But we don't handle that. */
572: fndecl = 0;
573: }
574: else
575: {
576: if (!flag_no_inline
577: && fndecl != current_function_decl
578: && DECL_SAVED_INSNS (fndecl))
579: is_integrable = 1;
580: else if (! TREE_ADDRESSABLE (fndecl))
581: {
582: /* In case this function later becomes inlinable,
583: record that there was already a non-inline call to it.
584:
585: Use abstraction instead of setting TREE_ADDRESSABLE
586: directly. */
587: if (DECL_INLINE (fndecl) && extra_warnings && warn_inline
588: && !flag_no_inline)
589: warning_with_decl (fndecl, "can't inline call to `%s' which was declared inline");
590: mark_addressable (fndecl);
591: }
592:
593: if (TREE_READONLY (fndecl) && ! TREE_THIS_VOLATILE (fndecl)
594: && TYPE_MODE (TREE_TYPE (exp)) != VOIDmode)
595: is_const = 1;
596:
597: if (TREE_THIS_VOLATILE (fndecl))
598: is_volatile = 1;
599: }
600: }
601:
602: #ifdef REG_PARM_STACK_SPACE
603: #ifdef MAYBE_REG_PARM_STACK_SPACE
604: reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
605: #else
606: reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
607: #endif
608: #endif
609:
610: /* Warn if this value is an aggregate type,
611: regardless of which calling convention we are using for it. */
612: if (warn_aggregate_return
613: && (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
614: || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE
615: || TREE_CODE (TREE_TYPE (exp)) == QUAL_UNION_TYPE
616: || TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE))
617: warning ("function call has aggregate value");
618:
619: /* Set up a place to return a structure. */
620:
621: /* Cater to broken compilers. */
622: if (aggregate_value_p (exp))
623: {
624: /* This call returns a big structure. */
625: is_const = 0;
626:
627: #ifdef PCC_STATIC_STRUCT_RETURN
628: {
629: pcc_struct_value = 1;
630: is_integrable = 0; /* Easier than making that case work right. */
631: }
632: #else /* not PCC_STATIC_STRUCT_RETURN */
633: {
634: struct_value_size = int_size_in_bytes (TREE_TYPE (exp));
635:
636: if (struct_value_size < 0)
637: abort ();
638:
639: if (target && GET_CODE (target) == MEM)
640: structure_value_addr = XEXP (target, 0);
641: else
642: {
643: /* Assign a temporary on the stack to hold the value. */
644:
645: /* For variable-sized objects, we must be called with a target
646: specified. If we were to allocate space on the stack here,
647: we would have no way of knowing when to free it. */
648:
649: structure_value_addr
650: = XEXP (assign_stack_temp (BLKmode, struct_value_size, 1), 0);
651: target = 0;
652: }
653: }
654: #endif /* not PCC_STATIC_STRUCT_RETURN */
655: }
656:
657: /* If called function is inline, try to integrate it. */
658:
659: if (is_integrable)
660: {
661: rtx temp;
662: rtx before_call = get_last_insn ();
663:
664: temp = expand_inline_function (fndecl, actparms, target,
665: ignore, TREE_TYPE (exp),
666: structure_value_addr);
667:
668: /* If inlining succeeded, return. */
669: if ((HOST_WIDE_INT) temp != -1)
670: {
671: /* Perform all cleanups needed for the arguments of this call
672: (i.e. destructors in C++). It is ok if these destructors
673: clobber RETURN_VALUE_REG, because the only time we care about
674: this is when TARGET is that register. But in C++, we take
675: care to never return that register directly. */
676: expand_cleanups_to (old_cleanups);
677:
678: #ifdef ACCUMULATE_OUTGOING_ARGS
679: /* If the outgoing argument list must be preserved, push
680: the stack before executing the inlined function if it
681: makes any calls. */
682:
683: for (i = reg_parm_stack_space - 1; i >= 0; i--)
684: if (i < highest_outgoing_arg_in_use && stack_usage_map[i] != 0)
685: break;
686:
687: if (stack_arg_under_construction || i >= 0)
688: {
689: rtx insn = NEXT_INSN (before_call), seq;
690:
691: /* Look for a call in the inline function code.
692: If OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) is
693: nonzero then there is a call and it is not necessary
694: to scan the insns. */
695:
696: if (OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl)) == 0)
697: for (; insn; insn = NEXT_INSN (insn))
698: if (GET_CODE (insn) == CALL_INSN)
699: break;
700:
701: if (insn)
702: {
703: /* Reserve enough stack space so that the largest
704: argument list of any function call in the inline
705: function does not overlap the argument list being
706: evaluated. This is usually an overestimate because
707: allocate_dynamic_stack_space reserves space for an
708: outgoing argument list in addition to the requested
709: space, but there is no way to ask for stack space such
710: that an argument list of a certain length can be
711: safely constructed. */
712:
713: int adjust = OUTGOING_ARGS_SIZE (DECL_SAVED_INSNS (fndecl));
714: #ifdef REG_PARM_STACK_SPACE
715: /* Add the stack space reserved for register arguments
716: in the inline function. What is really needed is the
717: largest value of reg_parm_stack_space in the inline
718: function, but that is not available. Using the current
719: value of reg_parm_stack_space is wrong, but gives
720: correct results on all supported machines. */
721: adjust += reg_parm_stack_space;
722: #endif
723: start_sequence ();
724: emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
725: allocate_dynamic_stack_space (GEN_INT (adjust),
726: NULL_RTX, BITS_PER_UNIT);
727: seq = get_insns ();
728: end_sequence ();
729: emit_insns_before (seq, NEXT_INSN (before_call));
730: emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
731: }
732: }
733: #endif
734:
735: /* If the result is equivalent to TARGET, return TARGET to simplify
736: checks in store_expr. They can be equivalent but not equal in the
737: case of a function that returns BLKmode. */
738: if (temp != target && rtx_equal_p (temp, target))
739: return target;
740: return temp;
741: }
742:
743: /* If inlining failed, mark FNDECL as needing to be compiled
744: separately after all. */
745: mark_addressable (fndecl);
746: }
747:
748: /* When calling a const function, we must pop the stack args right away,
749: so that the pop is deleted or moved with the call. */
750: if (is_const)
751: NO_DEFER_POP;
752:
753: function_call_count++;
754:
755: if (fndecl && DECL_NAME (fndecl))
756: name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
757:
758: /* On some machines (such as the PA) indirect calls have a different
759: calling convention than normal calls. FUNCTION_ARG in the target
760: description can look at current_call_is_indirect to determine which
761: calling convention to use. */
762: current_call_is_indirect = (fndecl == 0);
763: #if 0
764: = TREE_CODE (TREE_OPERAND (exp, 0)) == NON_LVALUE_EXPR ? 1 : 0;
765: #endif
766:
767: #if 0
768: /* Unless it's a call to a specific function that isn't alloca,
769: if it has one argument, we must assume it might be alloca. */
770:
771: may_be_alloca =
772: (!(fndecl != 0 && strcmp (name, "alloca"))
773: && actparms != 0
774: && TREE_CHAIN (actparms) == 0);
775: #else
776: /* We assume that alloca will always be called by name. It
777: makes no sense to pass it as a pointer-to-function to
778: anything that does not understand its behavior. */
779: may_be_alloca =
780: (name && ((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
781: && name[0] == 'a'
782: && ! strcmp (name, "alloca"))
783: || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
784: && name[0] == '_'
785: && ! strcmp (name, "__builtin_alloca"))));
786: #endif
787:
788: /* See if this is a call to a function that can return more than once
789: or a call to longjmp. */
790:
791: returns_twice = 0;
792: is_longjmp = 0;
793:
794: if (name != 0 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 15)
795: {
796: char *tname = name;
797:
798: /* Disregard prefix _, __ or __x. */
799: if (name[0] == '_')
800: {
801: if (name[1] == '_' && name[2] == 'x')
802: tname += 3;
803: else if (name[1] == '_')
804: tname += 2;
805: else
806: tname += 1;
807: }
808:
809: if (tname[0] == 's')
810: {
811: returns_twice
812: = ((tname[1] == 'e'
813: && (! strcmp (tname, "setjmp")
814: || ! strcmp (tname, "setjmp_syscall")))
815: || (tname[1] == 'i'
816: && ! strcmp (tname, "sigsetjmp"))
817: || (tname[1] == 'a'
818: && ! strcmp (tname, "savectx")));
819: if (tname[1] == 'i'
820: && ! strcmp (tname, "siglongjmp"))
821: is_longjmp = 1;
822: }
823: else if ((tname[0] == 'q' && tname[1] == 's'
824: && ! strcmp (tname, "qsetjmp"))
825: || (tname[0] == 'v' && tname[1] == 'f'
826: && ! strcmp (tname, "vfork")))
827: returns_twice = 1;
828:
829: else if (tname[0] == 'l' && tname[1] == 'o'
830: && ! strcmp (tname, "longjmp"))
831: is_longjmp = 1;
832: }
833:
834: if (may_be_alloca)
835: current_function_calls_alloca = 1;
836:
837: /* Don't let pending stack adjusts add up to too much.
838: Also, do all pending adjustments now
839: if there is any chance this might be a call to alloca. */
840:
841: if (pending_stack_adjust >= 32
842: || (pending_stack_adjust > 0 && may_be_alloca))
843: do_pending_stack_adjust ();
844:
845: /* Operand 0 is a pointer-to-function; get the type of the function. */
846: funtype = TREE_TYPE (TREE_OPERAND (exp, 0));
847: if (TREE_CODE (funtype) != POINTER_TYPE)
848: abort ();
849: funtype = TREE_TYPE (funtype);
850:
851: /* Push the temporary stack slot level so that we can free temporaries used
852: by each of the arguments separately. */
853: push_temp_slots ();
854:
855: /* Start updating where the next arg would go. */
856: INIT_CUMULATIVE_ARGS (args_so_far, funtype, NULL_RTX);
857:
858: /* If struct_value_rtx is 0, it means pass the address
859: as if it were an extra parameter. */
860: if (structure_value_addr && struct_value_rtx == 0)
861: {
862: #ifdef ACCUMULATE_OUTGOING_ARGS
863: /* If the stack will be adjusted, make sure the structure address
864: does not refer to virtual_outgoing_args_rtx. */
865: rtx temp = (stack_arg_under_construction
866: ? copy_addr_to_reg (structure_value_addr)
867: : force_reg (Pmode, structure_value_addr));
868: #else
869: rtx temp = force_reg (Pmode, structure_value_addr);
870: #endif
871:
872: actparms
873: = tree_cons (error_mark_node,
874: make_tree (build_pointer_type (TREE_TYPE (funtype)),
875: temp),
876: actparms);
877: structure_value_addr_parm = 1;
878: }
879:
880: /* Count the arguments and set NUM_ACTUALS. */
881: for (p = actparms, i = 0; p; p = TREE_CHAIN (p)) i++;
882: num_actuals = i;
883:
884: /* Compute number of named args.
885: Normally, don't include the last named arg if anonymous args follow.
886: (If no anonymous args follow, the result of list_length
887: is actually one too large.)
888:
889: If SETUP_INCOMING_VARARGS is defined, this machine will be able to
890: place unnamed args that were passed in registers into the stack. So
891: treat all args as named. This allows the insns emitting for a specific
892: argument list to be independent of the function declaration.
893:
894: If SETUP_INCOMING_VARARGS is not defined, we do not have any reliable
895: way to pass unnamed args in registers, so we must force them into
896: memory. */
897: #ifndef SETUP_INCOMING_VARARGS
898: if (TYPE_ARG_TYPES (funtype) != 0)
899: n_named_args
900: = list_length (TYPE_ARG_TYPES (funtype)) - 1
901: /* Count the struct value address, if it is passed as a parm. */
902: + structure_value_addr_parm;
903: else
904: #endif
905: /* If we know nothing, treat all args as named. */
906: n_named_args = num_actuals;
907:
908: /* Make a vector to hold all the information about each arg. */
909: args = (struct arg_data *) alloca (num_actuals * sizeof (struct arg_data));
910: bzero (args, num_actuals * sizeof (struct arg_data));
911:
912: args_size.constant = 0;
913: args_size.var = 0;
914:
915: /* In this loop, we consider args in the order they are written.
916: We fill up ARGS from the front of from the back if necessary
917: so that in any case the first arg to be pushed ends up at the front. */
918:
919: #ifdef PUSH_ARGS_REVERSED
920: i = num_actuals - 1, inc = -1;
921: /* In this case, must reverse order of args
922: so that we compute and push the last arg first. */
923: #else
924: i = 0, inc = 1;
925: #endif
926:
927: /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
928: for (p = actparms, argpos = 0; p; p = TREE_CHAIN (p), i += inc, argpos++)
929: {
930: tree type = TREE_TYPE (TREE_VALUE (p));
931: enum machine_mode mode;
932:
933: args[i].tree_value = TREE_VALUE (p);
934:
935: /* Replace erroneous argument with constant zero. */
936: if (type == error_mark_node || TYPE_SIZE (type) == 0)
937: args[i].tree_value = integer_zero_node, type = integer_type_node;
938:
939: /* Decide where to pass this arg.
940:
941: args[i].reg is nonzero if all or part is passed in registers.
942:
943: args[i].partial is nonzero if part but not all is passed in registers,
944: and the exact value says how many words are passed in registers.
945:
946: args[i].pass_on_stack is nonzero if the argument must at least be
947: computed on the stack. It may then be loaded back into registers
948: if args[i].reg is nonzero.
949:
950: These decisions are driven by the FUNCTION_... macros and must agree
951: with those made by function.c. */
952:
953: /* See if this argument should be passed by invisible reference. */
954: if ((TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
955: && contains_placeholder_p (TYPE_SIZE (type)))
956: #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
957: || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, TYPE_MODE (type),
958: type, argpos < n_named_args)
959: #endif
960: )
961: {
962: #ifdef FUNCTION_ARG_CALLEE_COPIES
963: if (FUNCTION_ARG_CALLEE_COPIES (args_so_far, TYPE_MODE (type), type,
964: argpos < n_named_args)
965: /* If it's in a register, we must make a copy of it too. */
966: /* ??? Is this a sufficient test? Is there a better one? */
967: && !(TREE_CODE (args[i].tree_value) == VAR_DECL
968: && REG_P (DECL_RTL (args[i].tree_value))))
969: {
970: args[i].tree_value = build1 (ADDR_EXPR,
971: build_pointer_type (type),
972: args[i].tree_value);
973: type = build_pointer_type (type);
974: }
975: else
976: #endif
977: {
978: /* We make a copy of the object and pass the address to the
979: function being called. */
980: rtx copy;
981:
982: if (TYPE_SIZE (type) == 0
983: || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
984: {
985: /* This is a variable-sized object. Make space on the stack
986: for it. */
987: rtx size_rtx = expr_size (TREE_VALUE (p));
988:
989: if (old_stack_level == 0)
990: {
991: emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
992: old_pending_adj = pending_stack_adjust;
993: pending_stack_adjust = 0;
994: }
995:
996: copy = gen_rtx (MEM, BLKmode,
997: allocate_dynamic_stack_space (size_rtx,
998: NULL_RTX,
999: TYPE_ALIGN (type)));
1000: }
1001: else
1002: {
1003: int size = int_size_in_bytes (type);
1004: copy = assign_stack_temp (TYPE_MODE (type), size, 1);
1005: }
1006:
1007: MEM_IN_STRUCT_P (copy)
1008: = (TREE_CODE (type) == RECORD_TYPE
1009: || TREE_CODE (type) == UNION_TYPE
1010: || TREE_CODE (type) == QUAL_UNION_TYPE
1011: || TREE_CODE (type) == ARRAY_TYPE);
1012:
1013: store_expr (args[i].tree_value, copy, 0);
1014:
1015: args[i].tree_value = build1 (ADDR_EXPR,
1016: build_pointer_type (type),
1017: make_tree (type, copy));
1018: type = build_pointer_type (type);
1019: }
1020: }
1021:
1022: mode = TYPE_MODE (type);
1023:
1024: #ifdef PROMOTE_FUNCTION_ARGS
1025: /* Compute the mode in which the arg is actually to be extended to. */
1026: if (TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == ENUMERAL_TYPE
1027: || TREE_CODE (type) == BOOLEAN_TYPE || TREE_CODE (type) == CHAR_TYPE
1028: || TREE_CODE (type) == REAL_TYPE || TREE_CODE (type) == POINTER_TYPE
1029: || TREE_CODE (type) == OFFSET_TYPE)
1030: {
1031: int unsignedp = TREE_UNSIGNED (type);
1032: PROMOTE_MODE (mode, unsignedp, type);
1033: args[i].unsignedp = unsignedp;
1034: }
1035: #endif
1036:
1037: args[i].mode = mode;
1038: args[i].reg = FUNCTION_ARG (args_so_far, mode, type,
1039: argpos < n_named_args);
1040: #ifdef FUNCTION_ARG_PARTIAL_NREGS
1041: if (args[i].reg)
1042: args[i].partial
1043: = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, type,
1044: argpos < n_named_args);
1045: #endif
1046:
1047: args[i].pass_on_stack = MUST_PASS_IN_STACK (mode, type);
1048:
1049: /* If FUNCTION_ARG returned an (expr_list (nil) FOO), it means that
1050: we are to pass this arg in the register(s) designated by FOO, but
1051: also to pass it in the stack. */
1052: if (args[i].reg && GET_CODE (args[i].reg) == EXPR_LIST
1053: && XEXP (args[i].reg, 0) == 0)
1054: args[i].pass_on_stack = 1, args[i].reg = XEXP (args[i].reg, 1);
1055:
1056: /* If this is an addressable type, we must preallocate the stack
1057: since we must evaluate the object into its final location.
1058:
1059: If this is to be passed in both registers and the stack, it is simpler
1060: to preallocate. */
1061: if (TREE_ADDRESSABLE (type)
1062: || (args[i].pass_on_stack && args[i].reg != 0))
1063: must_preallocate = 1;
1064:
1065: /* If this is an addressable type, we cannot pre-evaluate it. Thus,
1066: we cannot consider this function call constant. */
1067: if (TREE_ADDRESSABLE (type))
1068: is_const = 0;
1069:
1070: /* Compute the stack-size of this argument. */
1071: if (args[i].reg == 0 || args[i].partial != 0
1072: #ifdef REG_PARM_STACK_SPACE
1073: || reg_parm_stack_space > 0
1074: #endif
1075: || args[i].pass_on_stack)
1076: locate_and_pad_parm (mode, type,
1077: #ifdef STACK_PARMS_IN_REG_PARM_AREA
1078: 1,
1079: #else
1080: args[i].reg != 0,
1081: #endif
1082: fndecl, &args_size, &args[i].offset,
1083: &args[i].size);
1084:
1085: #ifndef ARGS_GROW_DOWNWARD
1086: args[i].slot_offset = args_size;
1087: #endif
1088:
1089: #ifndef REG_PARM_STACK_SPACE
1090: /* If a part of the arg was put into registers,
1091: don't include that part in the amount pushed. */
1092: if (! args[i].pass_on_stack)
1093: args[i].size.constant -= ((args[i].partial * UNITS_PER_WORD)
1094: / (PARM_BOUNDARY / BITS_PER_UNIT)
1095: * (PARM_BOUNDARY / BITS_PER_UNIT));
1096: #endif
1097:
1098: /* Update ARGS_SIZE, the total stack space for args so far. */
1099:
1100: args_size.constant += args[i].size.constant;
1101: if (args[i].size.var)
1102: {
1103: ADD_PARM_SIZE (args_size, args[i].size.var);
1104: }
1105:
1106: /* Since the slot offset points to the bottom of the slot,
1107: we must record it after incrementing if the args grow down. */
1108: #ifdef ARGS_GROW_DOWNWARD
1109: args[i].slot_offset = args_size;
1110:
1111: args[i].slot_offset.constant = -args_size.constant;
1112: if (args_size.var)
1113: {
1114: SUB_PARM_SIZE (args[i].slot_offset, args_size.var);
1115: }
1116: #endif
1117:
1118: /* Increment ARGS_SO_FAR, which has info about which arg-registers
1119: have been used, etc. */
1120:
1121: FUNCTION_ARG_ADVANCE (args_so_far, TYPE_MODE (type), type,
1122: argpos < n_named_args);
1123: }
1124:
1125: #ifdef FINAL_REG_PARM_STACK_SPACE
1126: reg_parm_stack_space = FINAL_REG_PARM_STACK_SPACE (args_size.constant,
1127: args_size.var);
1128: #endif
1129:
1130: /* Compute the actual size of the argument block required. The variable
1131: and constant sizes must be combined, the size may have to be rounded,
1132: and there may be a minimum required size. */
1133:
1134: original_args_size = args_size;
1135: if (args_size.var)
1136: {
1137: /* If this function requires a variable-sized argument list, don't try to
1138: make a cse'able block for this call. We may be able to do this
1139: eventually, but it is too complicated to keep track of what insns go
1140: in the cse'able block and which don't. */
1141:
1142: is_const = 0;
1143: must_preallocate = 1;
1144:
1145: args_size.var = ARGS_SIZE_TREE (args_size);
1146: args_size.constant = 0;
1147:
1148: #ifdef STACK_BOUNDARY
1149: if (STACK_BOUNDARY != BITS_PER_UNIT)
1150: args_size.var = round_up (args_size.var, STACK_BYTES);
1151: #endif
1152:
1153: #ifdef REG_PARM_STACK_SPACE
1154: if (reg_parm_stack_space > 0)
1155: {
1156: args_size.var
1157: = size_binop (MAX_EXPR, args_size.var,
1158: size_int (REG_PARM_STACK_SPACE (fndecl)));
1159:
1160: #ifndef OUTGOING_REG_PARM_STACK_SPACE
1161: /* The area corresponding to register parameters is not to count in
1162: the size of the block we need. So make the adjustment. */
1163: args_size.var
1164: = size_binop (MINUS_EXPR, args_size.var,
1165: size_int (reg_parm_stack_space));
1166: #endif
1167: }
1168: #endif
1169: }
1170: else
1171: {
1172: #ifdef STACK_BOUNDARY
1173: args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
1174: / STACK_BYTES) * STACK_BYTES);
1175: #endif
1176:
1177: #ifdef REG_PARM_STACK_SPACE
1178: args_size.constant = MAX (args_size.constant,
1179: reg_parm_stack_space);
1180: #ifdef MAYBE_REG_PARM_STACK_SPACE
1181: if (reg_parm_stack_space == 0)
1182: args_size.constant = 0;
1183: #endif
1184: #ifndef OUTGOING_REG_PARM_STACK_SPACE
1185: args_size.constant -= reg_parm_stack_space;
1186: #endif
1187: #endif
1188: }
1189:
1190: /* See if we have or want to preallocate stack space.
1191:
1192: If we would have to push a partially-in-regs parm
1193: before other stack parms, preallocate stack space instead.
1194:
1195: If the size of some parm is not a multiple of the required stack
1196: alignment, we must preallocate.
1197:
1198: If the total size of arguments that would otherwise create a copy in
1199: a temporary (such as a CALL) is more than half the total argument list
1200: size, preallocation is faster.
1201:
1202: Another reason to preallocate is if we have a machine (like the m88k)
1203: where stack alignment is required to be maintained between every
1204: pair of insns, not just when the call is made. However, we assume here
1205: that such machines either do not have push insns (and hence preallocation
1206: would occur anyway) or the problem is taken care of with
1207: PUSH_ROUNDING. */
1208:
1209: if (! must_preallocate)
1210: {
1211: int partial_seen = 0;
1212: int copy_to_evaluate_size = 0;
1213:
1214: for (i = 0; i < num_actuals && ! must_preallocate; i++)
1215: {
1216: if (args[i].partial > 0 && ! args[i].pass_on_stack)
1217: partial_seen = 1;
1218: else if (partial_seen && args[i].reg == 0)
1219: must_preallocate = 1;
1220:
1221: if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1222: && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1223: || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1224: || TREE_CODE (args[i].tree_value) == COND_EXPR
1225: || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1226: copy_to_evaluate_size
1227: += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1228: }
1229:
1230: if (copy_to_evaluate_size * 2 >= args_size.constant
1231: && args_size.constant > 0)
1232: must_preallocate = 1;
1233: }
1234:
1235: /* If the structure value address will reference the stack pointer, we must
1236: stabilize it. We don't need to do this if we know that we are not going
1237: to adjust the stack pointer in processing this call. */
1238:
1239: if (structure_value_addr
1240: && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
1241: || reg_mentioned_p (virtual_outgoing_args_rtx, structure_value_addr))
1242: && (args_size.var
1243: #ifndef ACCUMULATE_OUTGOING_ARGS
1244: || args_size.constant
1245: #endif
1246: ))
1247: structure_value_addr = copy_to_reg (structure_value_addr);
1248:
1249: /* If this function call is cse'able, precompute all the parameters.
1250: Note that if the parameter is constructed into a temporary, this will
1251: cause an additional copy because the parameter will be constructed
1252: into a temporary location and then copied into the outgoing arguments.
1253: If a parameter contains a call to alloca and this function uses the
1254: stack, precompute the parameter. */
1255:
1256: /* If we preallocated the stack space, and some arguments must be passed
1257: on the stack, then we must precompute any parameter which contains a
1258: function call which will store arguments on the stack.
1259: Otherwise, evaluating the parameter may clobber previous parameters
1260: which have already been stored into the stack. */
1261:
1262: for (i = 0; i < num_actuals; i++)
1263: if (is_const
1264: || ((args_size.var != 0 || args_size.constant != 0)
1265: && calls_function (args[i].tree_value, 1))
1266: || (must_preallocate && (args_size.var != 0 || args_size.constant != 0)
1267: && calls_function (args[i].tree_value, 0)))
1268: {
1269: args[i].initial_value = args[i].value
1270: = expand_expr (args[i].tree_value, NULL_RTX, VOIDmode, 0);
1271:
1272: if (GET_MODE (args[i].value ) != VOIDmode
1273: && GET_MODE (args[i].value) != args[i].mode)
1274: args[i].value = convert_to_mode (args[i].mode, args[i].value,
1275: args[i].unsignedp);
1276: preserve_temp_slots (args[i].value);
1277:
1278: free_temp_slots ();
1279:
1280: /* ANSI doesn't require a sequence point here,
1281: but PCC has one, so this will avoid some problems. */
1282: emit_queue ();
1283: }
1284:
1285: /* Now we are about to start emitting insns that can be deleted
1286: if a libcall is deleted. */
1287: if (is_const)
1288: start_sequence ();
1289:
1290: /* If we have no actual push instructions, or shouldn't use them,
1291: make space for all args right now. */
1292:
1293: if (args_size.var != 0)
1294: {
1295: if (old_stack_level == 0)
1296: {
1297: emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1298: old_pending_adj = pending_stack_adjust;
1299: pending_stack_adjust = 0;
1300: #ifdef ACCUMULATE_OUTGOING_ARGS
1301: /* stack_arg_under_construction says whether a stack arg is
1302: being constructed at the old stack level. Pushing the stack
1303: gets a clean outgoing argument block. */
1304: old_stack_arg_under_construction = stack_arg_under_construction;
1305: stack_arg_under_construction = 0;
1306: #endif
1307: }
1308: argblock = push_block (ARGS_SIZE_RTX (args_size), 0, 0);
1309: }
1310: else if (must_preallocate)
1311: {
1312: /* Note that we must go through the motions of allocating an argument
1313: block even if the size is zero because we may be storing args
1314: in the area reserved for register arguments, which may be part of
1315: the stack frame. */
1316: int needed = args_size.constant;
1317:
1318: #ifdef ACCUMULATE_OUTGOING_ARGS
1319: /* Store the maximum argument space used. It will be pushed by the
1320: prologue.
1321:
1322: Since the stack pointer will never be pushed, it is possible for
1323: the evaluation of a parm to clobber something we have already
1324: written to the stack. Since most function calls on RISC machines
1325: do not use the stack, this is uncommon, but must work correctly.
1326:
1327: Therefore, we save any area of the stack that was already written
1328: and that we are using. Here we set up to do this by making a new
1329: stack usage map from the old one. The actual save will be done
1330: by store_one_arg.
1331:
1332: Another approach might be to try to reorder the argument
1333: evaluations to avoid this conflicting stack usage. */
1334:
1335: if (needed > current_function_outgoing_args_size)
1336: current_function_outgoing_args_size = needed;
1337:
1338: #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1339: /* Since we will be writing into the entire argument area, the
1340: map must be allocated for its entire size, not just the part that
1341: is the responsibility of the caller. */
1342: needed += reg_parm_stack_space;
1343: #endif
1344:
1345: #ifdef ARGS_GROW_DOWNWARD
1346: highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
1347: needed + 1);
1348: #else
1349: highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
1350: #endif
1351: stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
1352:
1353: if (initial_highest_arg_in_use)
1354: bcopy (initial_stack_usage_map, stack_usage_map,
1355: initial_highest_arg_in_use);
1356:
1357: if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
1358: bzero (&stack_usage_map[initial_highest_arg_in_use],
1359: highest_outgoing_arg_in_use - initial_highest_arg_in_use);
1360: needed = 0;
1361:
1362: /* The address of the outgoing argument list must not be copied to a
1363: register here, because argblock would be left pointing to the
1364: wrong place after the call to allocate_dynamic_stack_space below. */
1365:
1366: argblock = virtual_outgoing_args_rtx;
1367:
1368: #else /* not ACCUMULATE_OUTGOING_ARGS */
1369: if (inhibit_defer_pop == 0)
1370: {
1371: /* Try to reuse some or all of the pending_stack_adjust
1372: to get this space. Maybe we can avoid any pushing. */
1373: if (needed > pending_stack_adjust)
1374: {
1375: needed -= pending_stack_adjust;
1376: pending_stack_adjust = 0;
1377: }
1378: else
1379: {
1380: pending_stack_adjust -= needed;
1381: needed = 0;
1382: }
1383: }
1384: /* Special case this because overhead of `push_block' in this
1385: case is non-trivial. */
1386: if (needed == 0)
1387: argblock = virtual_outgoing_args_rtx;
1388: else
1389: argblock = push_block (GEN_INT (needed), 0, 0);
1390:
1391: /* We only really need to call `copy_to_reg' in the case where push
1392: insns are going to be used to pass ARGBLOCK to a function
1393: call in ARGS. In that case, the stack pointer changes value
1394: from the allocation point to the call point, and hence
1395: the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
1396: But might as well always do it. */
1397: argblock = copy_to_reg (argblock);
1398: #endif /* not ACCUMULATE_OUTGOING_ARGS */
1399: }
1400:
1401:
1402: #ifdef ACCUMULATE_OUTGOING_ARGS
1403: /* The save/restore code in store_one_arg handles all cases except one:
1404: a constructor call (including a C function returning a BLKmode struct)
1405: to initialize an argument. */
1406: if (stack_arg_under_construction)
1407: {
1408: #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
1409: rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
1410: #else
1411: rtx push_size = GEN_INT (args_size.constant);
1412: #endif
1413: if (old_stack_level == 0)
1414: {
1415: emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
1416: old_pending_adj = pending_stack_adjust;
1417: pending_stack_adjust = 0;
1418: /* stack_arg_under_construction says whether a stack arg is
1419: being constructed at the old stack level. Pushing the stack
1420: gets a clean outgoing argument block. */
1421: old_stack_arg_under_construction = stack_arg_under_construction;
1422: stack_arg_under_construction = 0;
1423: /* Make a new map for the new argument list. */
1424: stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
1425: bzero (stack_usage_map, highest_outgoing_arg_in_use);
1426: highest_outgoing_arg_in_use = 0;
1427: }
1428: allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
1429: }
1430: /* If argument evaluation might modify the stack pointer, copy the
1431: address of the argument list to a register. */
1432: for (i = 0; i < num_actuals; i++)
1433: if (args[i].pass_on_stack)
1434: {
1435: argblock = copy_addr_to_reg (argblock);
1436: break;
1437: }
1438: #endif
1439:
1440:
1441: /* If we preallocated stack space, compute the address of each argument.
1442: We need not ensure it is a valid memory address here; it will be
1443: validized when it is used. */
1444: if (argblock)
1445: {
1446: rtx arg_reg = argblock;
1447: int arg_offset = 0;
1448:
1449: if (GET_CODE (argblock) == PLUS)
1450: arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1451:
1452: for (i = 0; i < num_actuals; i++)
1453: {
1454: rtx offset = ARGS_SIZE_RTX (args[i].offset);
1455: rtx slot_offset = ARGS_SIZE_RTX (args[i].slot_offset);
1456: rtx addr;
1457:
1458: /* Skip this parm if it will not be passed on the stack. */
1459: if (! args[i].pass_on_stack && args[i].reg != 0)
1460: continue;
1461:
1462: if (GET_CODE (offset) == CONST_INT)
1463: addr = plus_constant (arg_reg, INTVAL (offset));
1464: else
1465: addr = gen_rtx (PLUS, Pmode, arg_reg, offset);
1466:
1467: addr = plus_constant (addr, arg_offset);
1468: args[i].stack = gen_rtx (MEM, args[i].mode, addr);
1469: MEM_IN_STRUCT_P (args[i].stack)
1470: = (TREE_CODE (TREE_TYPE (args[i].tree_value)) == RECORD_TYPE
1471: || TREE_CODE (TREE_TYPE (args[i].tree_value)) == UNION_TYPE
1472: || TREE_CODE (TREE_TYPE (args[i].tree_value)) == QUAL_UNION_TYPE
1473: || TREE_CODE (TREE_TYPE (args[i].tree_value)) == ARRAY_TYPE);
1474:
1475: if (GET_CODE (slot_offset) == CONST_INT)
1476: addr = plus_constant (arg_reg, INTVAL (slot_offset));
1477: else
1478: addr = gen_rtx (PLUS, Pmode, arg_reg, slot_offset);
1479:
1480: addr = plus_constant (addr, arg_offset);
1481: args[i].stack_slot = gen_rtx (MEM, args[i].mode, addr);
1482: }
1483: }
1484:
1485: #ifdef PUSH_ARGS_REVERSED
1486: #ifdef STACK_BOUNDARY
1487: /* If we push args individually in reverse order, perform stack alignment
1488: before the first push (the last arg). */
1489: if (argblock == 0)
1490: anti_adjust_stack (GEN_INT (args_size.constant
1491: - original_args_size.constant));
1492: #endif
1493: #endif
1494:
1495: /* Don't try to defer pops if preallocating, not even from the first arg,
1496: since ARGBLOCK probably refers to the SP. */
1497: if (argblock)
1498: NO_DEFER_POP;
1499:
1500: /* Get the function to call, in the form of RTL. */
1501: if (fndecl)
1502: {
1503: /* If this is the first use of the function, see if we need to
1504: make an external definition for it. */
1505: if (! TREE_USED (fndecl))
1506: {
1507: assemble_external (fndecl);
1508: TREE_USED (fndecl) = 1;
1509: }
1510:
1511: /* Get a SYMBOL_REF rtx for the function address. */
1512: funexp = XEXP (DECL_RTL (fndecl), 0);
1513: }
1514: else
1515: /* Generate an rtx (probably a pseudo-register) for the address. */
1516: {
1517: funexp = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0);
1518: free_temp_slots (); /* FUNEXP can't be BLKmode */
1519: emit_queue ();
1520: }
1521:
1522: /* Figure out the register where the value, if any, will come back. */
1523: valreg = 0;
1524: if (TYPE_MODE (TREE_TYPE (exp)) != VOIDmode
1525: && ! structure_value_addr)
1526: {
1527: if (pcc_struct_value)
1528: valreg = hard_function_value (build_pointer_type (TREE_TYPE (exp)),
1529: fndecl);
1530: else
1531: valreg = hard_function_value (TREE_TYPE (exp), fndecl);
1532: }
1533:
1534: /* Precompute all register parameters. It isn't safe to compute anything
1535: once we have started filling any specific hard regs. */
1536: reg_parm_seen = 0;
1537: for (i = 0; i < num_actuals; i++)
1538: if (args[i].reg != 0 && ! args[i].pass_on_stack)
1539: {
1540: reg_parm_seen = 1;
1541:
1542: if (args[i].value == 0)
1543: {
1544: args[i].value = expand_expr (args[i].tree_value, NULL_RTX,
1545: VOIDmode, 0);
1546: preserve_temp_slots (args[i].value);
1547: free_temp_slots ();
1548:
1549: /* ANSI doesn't require a sequence point here,
1550: but PCC has one, so this will avoid some problems. */
1551: emit_queue ();
1552: }
1553:
1554: /* If we are to promote the function arg to a wider mode,
1555: do it now. */
1556:
1557: if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
1558: args[i].value
1559: = convert_modes (args[i].mode,
1560: TYPE_MODE (TREE_TYPE (args[i].tree_value)),
1561: args[i].value, args[i].unsignedp);
1562: }
1563:
1564: #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)
1565: /* The argument list is the property of the called routine and it
1566: may clobber it. If the fixed area has been used for previous
1567: parameters, we must save and restore it.
1568:
1569: Here we compute the boundary of the that needs to be saved, if any. */
1570:
1571: #ifdef ARGS_GROW_DOWNWARD
1572: for (i = 0; i < reg_parm_stack_space + 1; i++)
1573: #else
1574: for (i = 0; i < reg_parm_stack_space; i++)
1575: #endif
1576: {
1577: if (i >= highest_outgoing_arg_in_use
1578: || stack_usage_map[i] == 0)
1579: continue;
1580:
1581: if (low_to_save == -1)
1582: low_to_save = i;
1583:
1584: high_to_save = i;
1585: }
1586:
1587: if (low_to_save >= 0)
1588: {
1589: int num_to_save = high_to_save - low_to_save + 1;
1590: enum machine_mode save_mode
1591: = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1592: rtx stack_area;
1593:
1594: /* If we don't have the required alignment, must do this in BLKmode. */
1595: if ((low_to_save & (MIN (GET_MODE_SIZE (save_mode),
1596: BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1597: save_mode = BLKmode;
1598:
1599: stack_area = gen_rtx (MEM, save_mode,
1600: memory_address (save_mode,
1601:
1602: #ifdef ARGS_GROW_DOWNWARD
1603: plus_constant (argblock,
1604: - high_to_save)
1605: #else
1606: plus_constant (argblock,
1607: low_to_save)
1608: #endif
1609: ));
1610: if (save_mode == BLKmode)
1611: {
1612: save_area = assign_stack_temp (BLKmode, num_to_save, 1);
1613: emit_block_move (validize_mem (save_area), stack_area,
1614: GEN_INT (num_to_save),
1615: PARM_BOUNDARY / BITS_PER_UNIT);
1616: }
1617: else
1618: {
1619: save_area = gen_reg_rtx (save_mode);
1620: emit_move_insn (save_area, stack_area);
1621: }
1622: }
1623: #endif
1624:
1625:
1626: /* Now store (and compute if necessary) all non-register parms.
1627: These come before register parms, since they can require block-moves,
1628: which could clobber the registers used for register parms.
1629: Parms which have partial registers are not stored here,
1630: but we do preallocate space here if they want that. */
1631:
1632: for (i = 0; i < num_actuals; i++)
1633: if (args[i].reg == 0 || args[i].pass_on_stack)
1634: store_one_arg (&args[i], argblock, may_be_alloca,
1635: args_size.var != 0, fndecl, reg_parm_stack_space);
1636:
1637: #ifdef STRICT_ALIGNMENT
1638: /* If we have a parm that is passed in registers but not in memory
1639: and whose alignment does not permit a direct copy into registers,
1640: make a group of pseudos that correspond to each register that we
1641: will later fill. */
1642:
1643: for (i = 0; i < num_actuals; i++)
1644: if (args[i].reg != 0 && ! args[i].pass_on_stack
1645: && args[i].mode == BLKmode
1646: && (TYPE_ALIGN (TREE_TYPE (args[i].tree_value))
1647: < MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1648: {
1649: int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1650: int big_endian_correction = 0;
1651:
1652: args[i].n_aligned_regs
1653: = args[i].partial ? args[i].partial
1654: : (bytes + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1655:
1656: args[i].aligned_regs = (rtx *) alloca (sizeof (rtx)
1657: * args[i].n_aligned_regs);
1658:
1659: /* Structures smaller than a word are aligned to the least signifcant
1660: byte (to the right). On a BYTES_BIG_ENDIAN machine, this means we
1661: must skip the empty high order bytes when calculating the bit
1662: offset. */
1663: if (BYTES_BIG_ENDIAN && bytes < UNITS_PER_WORD)
1664: big_endian_correction = (BITS_PER_WORD - (bytes * BITS_PER_UNIT));
1665:
1666: for (j = 0; j < args[i].n_aligned_regs; j++)
1667: {
1668: rtx reg = gen_reg_rtx (word_mode);
1669: rtx word = operand_subword_force (args[i].value, j, BLKmode);
1670: int bitsize = TYPE_ALIGN (TREE_TYPE (args[i].tree_value));
1671: int bitpos;
1672:
1673: args[i].aligned_regs[j] = reg;
1674:
1675: /* Clobber REG and move each partword into it. Ensure we don't
1676: go past the end of the structure. Note that the loop below
1677: works because we've already verified that padding
1678: and endianness are compatible. */
1679:
1680: emit_insn (gen_rtx (CLOBBER, VOIDmode, reg));
1681:
1682: for (bitpos = 0;
1683: bitpos < BITS_PER_WORD && bytes > 0;
1684: bitpos += bitsize, bytes -= bitsize / BITS_PER_UNIT)
1685: {
1686: int xbitpos = bitpos + big_endian_correction;
1687:
1688: store_bit_field (reg, bitsize, xbitpos, word_mode,
1689: extract_bit_field (word, bitsize, bitpos, 1,
1690: NULL_RTX, word_mode,
1691: word_mode,
1692: bitsize / BITS_PER_UNIT,
1693: BITS_PER_WORD),
1694: bitsize / BITS_PER_UNIT, BITS_PER_WORD);
1695: }
1696: }
1697: }
1698: #endif
1699:
1700: /* Now store any partially-in-registers parm.
1701: This is the last place a block-move can happen. */
1702: if (reg_parm_seen)
1703: for (i = 0; i < num_actuals; i++)
1704: if (args[i].partial != 0 && ! args[i].pass_on_stack)
1705: store_one_arg (&args[i], argblock, may_be_alloca,
1706: args_size.var != 0, fndecl, reg_parm_stack_space);
1707:
1708: #ifndef PUSH_ARGS_REVERSED
1709: #ifdef STACK_BOUNDARY
1710: /* If we pushed args in forward order, perform stack alignment
1711: after pushing the last arg. */
1712: if (argblock == 0)
1713: anti_adjust_stack (GEN_INT (args_size.constant
1714: - original_args_size.constant));
1715: #endif
1716: #endif
1717:
1718: /* If register arguments require space on the stack and stack space
1719: was not preallocated, allocate stack space here for arguments
1720: passed in registers. */
1721: #if ! defined(ACCUMULATE_OUTGOING_ARGS) && defined(OUTGOING_REG_PARM_STACK_SPACE)
1722: if (must_preallocate == 0 && reg_parm_stack_space > 0)
1723: anti_adjust_stack (GEN_INT (reg_parm_stack_space));
1724: #endif
1725:
1726: /* Pass the function the address in which to return a structure value. */
1727: if (structure_value_addr && ! structure_value_addr_parm)
1728: {
1729: emit_move_insn (struct_value_rtx,
1730: force_reg (Pmode,
1731: force_operand (structure_value_addr,
1732: NULL_RTX)));
1733: if (GET_CODE (struct_value_rtx) == REG)
1734: {
1735: push_to_sequence (use_insns);
1736: emit_insn (gen_rtx (USE, VOIDmode, struct_value_rtx));
1737: use_insns = get_insns ();
1738: end_sequence ();
1739: }
1740: }
1741:
1742: /* Now do the register loads required for any wholly-register parms or any
1743: parms which are passed both on the stack and in a register. Their
1744: expressions were already evaluated.
1745:
1746: Mark all register-parms as living through the call, putting these USE
1747: insns in a list headed by USE_INSNS. */
1748:
1749: for (i = 0; i < num_actuals; i++)
1750: {
1751: rtx list = args[i].reg;
1752: int partial = args[i].partial;
1753:
1754: while (list)
1755: {
1756: rtx reg;
1757: int nregs;
1758:
1759: /* Process each register that needs to get this arg. */
1760: if (GET_CODE (list) == EXPR_LIST)
1761: reg = XEXP (list, 0), list = XEXP (list, 1);
1762: else
1763: reg = list, list = 0;
1764:
1765: /* Set to non-zero if must move a word at a time, even if just one
1766: word (e.g, partial == 1 && mode == DFmode). Set to zero if
1767: we just use a normal move insn. */
1768: nregs = (partial ? partial
1769: : (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1770: ? ((int_size_in_bytes (TREE_TYPE (args[i].tree_value))
1771: + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
1772: : 0));
1773:
1774: /* If simple case, just do move. If normal partial, store_one_arg
1775: has already loaded the register for us. In all other cases,
1776: load the register(s) from memory. */
1777:
1778: if (nregs == 0)
1779: emit_move_insn (reg, args[i].value);
1780:
1781: #ifdef STRICT_ALIGNMENT
1782: /* If we have pre-computed the values to put in the registers in
1783: the case of non-aligned structures, copy them in now. */
1784:
1785: else if (args[i].n_aligned_regs != 0)
1786: for (j = 0; j < args[i].n_aligned_regs; j++)
1787: emit_move_insn (gen_rtx (REG, word_mode, REGNO (reg) + j),
1788: args[i].aligned_regs[j]);
1789: #endif
1790:
1791: else if (args[i].partial == 0 || args[i].pass_on_stack)
1792: move_block_to_reg (REGNO (reg),
1793: validize_mem (args[i].value), nregs,
1794: args[i].mode);
1795:
1796: #ifdef DUP_REG_ARG_LOAD
1797: DUP_REG_ARG_LOAD (name, nregs, reg, args[i].value, args[i].mode);
1798: #endif
1799:
1800: push_to_sequence (use_insns);
1801: if (nregs == 0)
1802: emit_insn (gen_rtx (USE, VOIDmode, reg));
1803: else
1804: use_regs (REGNO (reg), nregs);
1805: #ifdef USE_DUP_REG_ARG_LOAD
1806: USE_DUP_REG_ARG_LOAD (name, nregs, reg, args[i].mode);
1807: #endif
1808: use_insns = get_insns ();
1809: end_sequence ();
1810:
1811: /* PARTIAL referred only to the first register, so clear it for the
1812: next time. */
1813: partial = 0;
1814: }
1815: }
1816:
1817: /* Perform postincrements before actually calling the function. */
1818: emit_queue ();
1819:
1820: /* All arguments and registers used for the call must be set up by now! */
1821:
1822: funexp = prepare_call_address (funexp, fndecl, &use_insns);
1823:
1824: /* Generate the actual call instruction. */
1825: emit_call_1 (funexp, funtype, args_size.constant, struct_value_size,
1826: FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
1827: valreg, old_inhibit_defer_pop, use_insns, is_const);
1828:
1829: /* If call is cse'able, make appropriate pair of reg-notes around it.
1830: Test valreg so we don't crash; may safely ignore `const'
1831: if return type is void. */
1832: if (is_const && valreg != 0)
1833: {
1834: rtx note = 0;
1835: rtx temp = gen_reg_rtx (GET_MODE (valreg));
1836: rtx insns;
1837:
1838: /* Construct an "equal form" for the value which mentions all the
1839: arguments in order as well as the function name. */
1840: #ifdef PUSH_ARGS_REVERSED
1841: for (i = 0; i < num_actuals; i++)
1842: note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1843: #else
1844: for (i = num_actuals - 1; i >= 0; i--)
1845: note = gen_rtx (EXPR_LIST, VOIDmode, args[i].initial_value, note);
1846: #endif
1847: note = gen_rtx (EXPR_LIST, VOIDmode, funexp, note);
1848:
1849: insns = get_insns ();
1850: end_sequence ();
1851:
1852: emit_libcall_block (insns, temp, valreg, note);
1853:
1854: valreg = temp;
1855: }
1856:
1857: /* For calls to `setjmp', etc., inform flow.c it should complain
1858: if nonvolatile values are live. */
1859:
1860: if (returns_twice)
1861: {
1862: emit_note (name, NOTE_INSN_SETJMP);
1863: current_function_calls_setjmp = 1;
1864: }
1865:
1866: if (is_longjmp)
1867: current_function_calls_longjmp = 1;
1868:
1869: /* Notice functions that cannot return.
1870: If optimizing, insns emitted below will be dead.
1871: If not optimizing, they will exist, which is useful
1872: if the user uses the `return' command in the debugger. */
1873:
1874: if (is_volatile || is_longjmp)
1875: emit_barrier ();
1876:
1877: /* If value type not void, return an rtx for the value. */
1878:
1879: /* If there are cleanups to be called, don't use a hard reg as target. */
1880: if (cleanups_this_call != old_cleanups
1881: && target && REG_P (target)
1882: && REGNO (target) < FIRST_PSEUDO_REGISTER)
1883: target = 0;
1884:
1885: if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode
1886: || ignore)
1887: {
1888: target = const0_rtx;
1889: }
1890: else if (structure_value_addr)
1891: {
1892: if (target == 0 || GET_CODE (target) != MEM)
1893: {
1894: target = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1895: memory_address (TYPE_MODE (TREE_TYPE (exp)),
1896: structure_value_addr));
1897: MEM_IN_STRUCT_P (target)
1898: = (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE
1899: || TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
1900: || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE
1901: || TREE_CODE (TREE_TYPE (exp)) == QUAL_UNION_TYPE);
1902: }
1903: }
1904: else if (pcc_struct_value)
1905: {
1906: if (target == 0)
1907: {
1908: /* We used leave the value in the location that it is
1909: returned in, but that causes problems if it is used more
1910: than once in one expression. Rather than trying to track
1911: when a copy is required, we always copy when TARGET is
1912: not specified. This calling sequence is only used on
1913: a few machines and TARGET is usually nonzero. */
1914: if (TYPE_MODE (TREE_TYPE (exp)) == BLKmode)
1915: {
1916: target = assign_stack_temp (BLKmode,
1917: int_size_in_bytes (TREE_TYPE (exp)),
1918: 0);
1919:
1920: /* Save this temp slot around the pop below. */
1921: preserve_temp_slots (target);
1922: }
1923: else
1924: target = gen_reg_rtx (TYPE_MODE (TREE_TYPE (exp)));
1925: }
1926:
1927: if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode)
1928: emit_move_insn (target, gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)),
1929: copy_to_reg (valreg)));
1930: else
1931: emit_block_move (target, gen_rtx (MEM, BLKmode, copy_to_reg (valreg)),
1932: expr_size (exp),
1933: TYPE_ALIGN (TREE_TYPE (exp)) / BITS_PER_UNIT);
1934: }
1935: else if (target && GET_MODE (target) == TYPE_MODE (TREE_TYPE (exp))
1936: && GET_MODE (target) == GET_MODE (valreg))
1937: /* TARGET and VALREG cannot be equal at this point because the latter
1938: would not have REG_FUNCTION_VALUE_P true, while the former would if
1939: it were referring to the same register.
1940:
1941: If they refer to the same register, this move will be a no-op, except
1942: when function inlining is being done. */
1943: emit_move_insn (target, valreg);
1944: else
1945: target = copy_to_reg (valreg);
1946:
1947: #ifdef PROMOTE_FUNCTION_RETURN
1948: /* If we promoted this return value, make the proper SUBREG. TARGET
1949: might be const0_rtx here, so be careful. */
1950: if (GET_CODE (target) == REG
1951: && GET_MODE (target) != TYPE_MODE (TREE_TYPE (exp)))
1952: {
1953: enum machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
1954: int unsignedp = TREE_UNSIGNED (TREE_TYPE (exp));
1955:
1956: if (TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE
1957: || TREE_CODE (TREE_TYPE (exp)) == ENUMERAL_TYPE
1958: || TREE_CODE (TREE_TYPE (exp)) == BOOLEAN_TYPE
1959: || TREE_CODE (TREE_TYPE (exp)) == CHAR_TYPE
1960: || TREE_CODE (TREE_TYPE (exp)) == REAL_TYPE
1961: || TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE
1962: || TREE_CODE (TREE_TYPE (exp)) == OFFSET_TYPE)
1963: {
1964: PROMOTE_MODE (mode, unsignedp, TREE_TYPE (exp));
1965: }
1966:
1967: /* If we didn't promote as expected, something is wrong. */
1968: if (mode != GET_MODE (target))
1969: abort ();
1970:
1971: target = gen_rtx (SUBREG, TYPE_MODE (TREE_TYPE (exp)), target, 0);
1972: SUBREG_PROMOTED_VAR_P (target) = 1;
1973: SUBREG_PROMOTED_UNSIGNED_P (target) = unsignedp;
1974: }
1975: #endif
1976:
1977: /* Perform all cleanups needed for the arguments of this call
1978: (i.e. destructors in C++). */
1979: expand_cleanups_to (old_cleanups);
1980:
1981: /* If size of args is variable or this was a constructor call for a stack
1982: argument, restore saved stack-pointer value. */
1983:
1984: if (old_stack_level)
1985: {
1986: emit_stack_restore (SAVE_BLOCK, old_stack_level, NULL_RTX);
1987: pending_stack_adjust = old_pending_adj;
1988: #ifdef ACCUMULATE_OUTGOING_ARGS
1989: stack_arg_under_construction = old_stack_arg_under_construction;
1990: highest_outgoing_arg_in_use = initial_highest_arg_in_use;
1991: stack_usage_map = initial_stack_usage_map;
1992: #endif
1993: }
1994: #ifdef ACCUMULATE_OUTGOING_ARGS
1995: else
1996: {
1997: #ifdef REG_PARM_STACK_SPACE
1998: if (save_area)
1999: {
2000: enum machine_mode save_mode = GET_MODE (save_area);
2001: rtx stack_area
2002: = gen_rtx (MEM, save_mode,
2003: memory_address (save_mode,
2004: #ifdef ARGS_GROW_DOWNWARD
2005: plus_constant (argblock, - high_to_save)
2006: #else
2007: plus_constant (argblock, low_to_save)
2008: #endif
2009: ));
2010:
2011: if (save_mode != BLKmode)
2012: emit_move_insn (stack_area, save_area);
2013: else
2014: emit_block_move (stack_area, validize_mem (save_area),
2015: GEN_INT (high_to_save - low_to_save + 1),
2016: PARM_BOUNDARY / BITS_PER_UNIT);
2017: }
2018: #endif
2019:
2020: /* If we saved any argument areas, restore them. */
2021: for (i = 0; i < num_actuals; i++)
2022: if (args[i].save_area)
2023: {
2024: enum machine_mode save_mode = GET_MODE (args[i].save_area);
2025: rtx stack_area
2026: = gen_rtx (MEM, save_mode,
2027: memory_address (save_mode,
2028: XEXP (args[i].stack_slot, 0)));
2029:
2030: if (save_mode != BLKmode)
2031: emit_move_insn (stack_area, args[i].save_area);
2032: else
2033: emit_block_move (stack_area, validize_mem (args[i].save_area),
2034: GEN_INT (args[i].size.constant),
2035: PARM_BOUNDARY / BITS_PER_UNIT);
2036: }
2037:
2038: highest_outgoing_arg_in_use = initial_highest_arg_in_use;
2039: stack_usage_map = initial_stack_usage_map;
2040: }
2041: #endif
2042:
2043: /* If this was alloca, record the new stack level for nonlocal gotos.
2044: Check for the handler slots since we might not have a save area
2045: for non-local gotos. */
2046:
2047: if (may_be_alloca && nonlocal_goto_handler_slot != 0)
2048: emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
2049:
2050: pop_temp_slots ();
2051:
2052: return target;
2053: }
2054:
2055: /* Output a library call to function FUN (a SYMBOL_REF rtx)
2056: (emitting the queue unless NO_QUEUE is nonzero),
2057: for a value of mode OUTMODE,
2058: with NARGS different arguments, passed as alternating rtx values
2059: and machine_modes to convert them to.
2060: The rtx values should have been passed through protect_from_queue already.
2061:
2062: NO_QUEUE will be true if and only if the library call is a `const' call
2063: which will be enclosed in REG_LIBCALL/REG_RETVAL notes; it is equivalent
2064: to the variable is_const in expand_call.
2065:
2066: NO_QUEUE must be true for const calls, because if it isn't, then
2067: any pending increment will be emitted between REG_LIBCALL/REG_RETVAL notes,
2068: and will be lost if the libcall sequence is optimized away.
2069:
2070: NO_QUEUE must be false for non-const calls, because if it isn't, the
2071: call insn will have its CONST_CALL_P bit set, and it will be incorrectly
2072: optimized. For instance, the instruction scheduler may incorrectly
2073: move memory references across the non-const call. */
2074:
2075: void
2076: emit_library_call (va_alist)
2077: va_dcl
2078: {
2079: va_list p;
2080: /* Total size in bytes of all the stack-parms scanned so far. */
2081: struct args_size args_size;
2082: /* Size of arguments before any adjustments (such as rounding). */
2083: struct args_size original_args_size;
2084: register int argnum;
2085: enum machine_mode outmode;
2086: int nargs;
2087: rtx fun;
2088: rtx orgfun;
2089: tree name;
2090: int inc;
2091: int count;
2092: rtx argblock = 0;
2093: CUMULATIVE_ARGS args_so_far;
2094: struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2095: struct args_size offset; struct args_size size; };
2096: struct arg *argvec;
2097: int old_inhibit_defer_pop = inhibit_defer_pop;
2098: int no_queue = 0;
2099: rtx use_insns;
2100: /* library calls are never indirect calls. */
2101: int current_call_is_indirect = 0;
2102:
2103: va_start (p);
2104: orgfun = fun = va_arg (p, rtx);
2105: no_queue = va_arg (p, int);
2106: outmode = va_arg (p, enum machine_mode);
2107: nargs = va_arg (p, int);
2108:
2109: name = get_identifier (XSTR (orgfun, 0));
2110:
2111: /* Copy all the libcall-arguments out of the varargs data
2112: and into a vector ARGVEC.
2113:
2114: Compute how to pass each argument. We only support a very small subset
2115: of the full argument passing conventions to limit complexity here since
2116: library functions shouldn't have many args. */
2117:
2118: argvec = (struct arg *) alloca (nargs * sizeof (struct arg));
2119:
2120: INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2121:
2122: args_size.constant = 0;
2123: args_size.var = 0;
2124:
2125: push_temp_slots ();
2126:
2127: for (count = 0; count < nargs; count++)
2128: {
2129: rtx val = va_arg (p, rtx);
2130: enum machine_mode mode = va_arg (p, enum machine_mode);
2131:
2132: /* We cannot convert the arg value to the mode the library wants here;
2133: must do it earlier where we know the signedness of the arg. */
2134: if (mode == BLKmode
2135: || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2136: abort ();
2137:
2138: /* On some machines, there's no way to pass a float to a library fcn.
2139: Pass it as a double instead. */
2140: #ifdef LIBGCC_NEEDS_DOUBLE
2141: if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2142: val = convert_to_mode (DFmode, val, 0), mode = DFmode;
2143: #endif
2144:
2145: /* There's no need to call protect_from_queue, because
2146: either emit_move_insn or emit_push_insn will do that. */
2147:
2148: /* Make sure it is a reasonable operand for a move or push insn. */
2149: if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2150: && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2151: val = force_operand (val, NULL_RTX);
2152:
2153: #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2154: if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2155: {
2156: /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2157: be viewed as just an efficiency improvement. */
2158: rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2159: emit_move_insn (slot, val);
2160: val = XEXP (slot, 0);
2161: mode = Pmode;
2162: }
2163: #endif
2164:
2165: argvec[count].value = val;
2166: argvec[count].mode = mode;
2167:
2168: argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2169: if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2170: abort ();
2171: #ifdef FUNCTION_ARG_PARTIAL_NREGS
2172: argvec[count].partial
2173: = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2174: #else
2175: argvec[count].partial = 0;
2176: #endif
2177:
2178: locate_and_pad_parm (mode, NULL_TREE,
2179: argvec[count].reg && argvec[count].partial == 0,
2180: NULL_TREE, &args_size, &argvec[count].offset,
2181: &argvec[count].size);
2182:
2183: if (argvec[count].size.var)
2184: abort ();
2185:
2186: #ifndef REG_PARM_STACK_SPACE
2187: if (argvec[count].partial)
2188: argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2189: #endif
2190:
2191: if (argvec[count].reg == 0 || argvec[count].partial != 0
2192: #ifdef REG_PARM_STACK_SPACE
2193: || 1
2194: #endif
2195: )
2196: args_size.constant += argvec[count].size.constant;
2197:
2198: #ifdef ACCUMULATE_OUTGOING_ARGS
2199: /* If this arg is actually passed on the stack, it might be
2200: clobbering something we already put there (this library call might
2201: be inside the evaluation of an argument to a function whose call
2202: requires the stack). This will only occur when the library call
2203: has sufficient args to run out of argument registers. Abort in
2204: this case; if this ever occurs, code must be added to save and
2205: restore the arg slot. */
2206:
2207: if (argvec[count].reg == 0 || argvec[count].partial != 0)
2208: abort ();
2209: #endif
2210:
2211: FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2212: }
2213: va_end (p);
2214:
2215: /* If this machine requires an external definition for library
2216: functions, write one out. */
2217: assemble_external_libcall (fun);
2218:
2219: original_args_size = args_size;
2220: #ifdef STACK_BOUNDARY
2221: args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2222: / STACK_BYTES) * STACK_BYTES);
2223: #endif
2224:
2225: #ifdef REG_PARM_STACK_SPACE
2226: args_size.constant = MAX (args_size.constant,
2227: REG_PARM_STACK_SPACE (NULL_TREE));
2228: #ifndef OUTGOING_REG_PARM_STACK_SPACE
2229: args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2230: #endif
2231: #endif
2232:
2233: #ifdef ACCUMULATE_OUTGOING_ARGS
2234: if (args_size.constant > current_function_outgoing_args_size)
2235: current_function_outgoing_args_size = args_size.constant;
2236: args_size.constant = 0;
2237: #endif
2238:
2239: #ifndef PUSH_ROUNDING
2240: argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2241: #endif
2242:
2243: #ifdef PUSH_ARGS_REVERSED
2244: #ifdef STACK_BOUNDARY
2245: /* If we push args individually in reverse order, perform stack alignment
2246: before the first push (the last arg). */
2247: if (argblock == 0)
2248: anti_adjust_stack (GEN_INT (args_size.constant
2249: - original_args_size.constant));
2250: #endif
2251: #endif
2252:
2253: #ifdef PUSH_ARGS_REVERSED
2254: inc = -1;
2255: argnum = nargs - 1;
2256: #else
2257: inc = 1;
2258: argnum = 0;
2259: #endif
2260:
2261: /* Push the args that need to be pushed. */
2262:
2263: for (count = 0; count < nargs; count++, argnum += inc)
2264: {
2265: register enum machine_mode mode = argvec[argnum].mode;
2266: register rtx val = argvec[argnum].value;
2267: rtx reg = argvec[argnum].reg;
2268: int partial = argvec[argnum].partial;
2269:
2270: if (! (reg != 0 && partial == 0))
2271: emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2272: argblock, GEN_INT (argvec[count].offset.constant));
2273: NO_DEFER_POP;
2274: }
2275:
2276: #ifndef PUSH_ARGS_REVERSED
2277: #ifdef STACK_BOUNDARY
2278: /* If we pushed args in forward order, perform stack alignment
2279: after pushing the last arg. */
2280: if (argblock == 0)
2281: anti_adjust_stack (GEN_INT (args_size.constant
2282: - original_args_size.constant));
2283: #endif
2284: #endif
2285:
2286: #ifdef PUSH_ARGS_REVERSED
2287: argnum = nargs - 1;
2288: #else
2289: argnum = 0;
2290: #endif
2291:
2292: /* Now load any reg parms into their regs. */
2293:
2294: for (count = 0; count < nargs; count++, argnum += inc)
2295: {
2296: register enum machine_mode mode = argvec[argnum].mode;
2297: register rtx val = argvec[argnum].value;
2298: rtx reg = argvec[argnum].reg;
2299: int partial = argvec[argnum].partial;
2300:
2301: if (reg != 0 && partial == 0)
2302: {
2303: emit_move_insn (reg, val);
2304: #ifdef DUP_REG_ARG_LOAD
2305: DUP_REG_ARG_LOAD (name, 0, reg, val, mode);
2306: #endif
2307: }
2308:
2309: NO_DEFER_POP;
2310: }
2311:
2312: /* For version 1.37, try deleting this entirely. */
2313: if (! no_queue)
2314: emit_queue ();
2315:
2316: /* Any regs containing parms remain in use through the call. */
2317: start_sequence ();
2318: for (count = 0; count < nargs; count++)
2319: if (argvec[count].reg != 0)
2320: {
2321: emit_insn (gen_rtx (USE, VOIDmode, argvec[count].reg));
2322: #ifdef USE_DUP_REG_ARG_LOAD
2323: USE_DUP_REG_ARG_LOAD (name, 0, argvec[count].reg, argvec[count].mode);
2324: #endif
2325: }
2326:
2327: use_insns = get_insns ();
2328: end_sequence ();
2329:
2330: fun = prepare_call_address (fun, NULL_TREE, &use_insns);
2331:
2332: /* Don't allow popping to be deferred, since then
2333: cse'ing of library calls could delete a call and leave the pop. */
2334: NO_DEFER_POP;
2335:
2336: /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2337: will set inhibit_defer_pop to that value. */
2338:
2339: emit_call_1 (fun, name, args_size.constant, 0,
2340: FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2341: outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
2342: old_inhibit_defer_pop + 1, use_insns, no_queue);
2343:
2344: pop_temp_slots ();
2345:
2346: /* Now restore inhibit_defer_pop to its actual original value. */
2347: OK_DEFER_POP;
2348: }
2349:
2350: /* Like emit_library_call except that an extra argument, VALUE,
2351: comes second and says where to store the result.
2352: (If VALUE is zero, this function chooses a convenient way
2353: to return the value.
2354:
2355: This function returns an rtx for where the value is to be found.
2356: If VALUE is nonzero, VALUE is returned. */
2357:
2358: rtx
2359: emit_library_call_value (va_alist)
2360: va_dcl
2361: {
2362: va_list p;
2363: /* Total size in bytes of all the stack-parms scanned so far. */
2364: struct args_size args_size;
2365: /* Size of arguments before any adjustments (such as rounding). */
2366: struct args_size original_args_size;
2367: register int argnum;
2368: enum machine_mode outmode;
2369: int nargs;
2370: rtx fun;
2371: rtx orgfun;
2372: int inc;
2373: int count;
2374: rtx argblock = 0;
2375: CUMULATIVE_ARGS args_so_far;
2376: struct arg { rtx value; enum machine_mode mode; rtx reg; int partial;
2377: struct args_size offset; struct args_size size; };
2378: struct arg *argvec;
2379: int old_inhibit_defer_pop = inhibit_defer_pop;
2380: int no_queue = 0;
2381: rtx use_insns;
2382: rtx value;
2383: rtx mem_value = 0;
2384: int pcc_struct_value = 0;
2385: int struct_value_size = 0;
2386: /* library calls are never indirect calls. */
2387: int current_call_is_indirect = 0;
2388:
2389: va_start (p);
2390: orgfun = fun = va_arg (p, rtx);
2391: value = va_arg (p, rtx);
2392: no_queue = va_arg (p, int);
2393: outmode = va_arg (p, enum machine_mode);
2394: nargs = va_arg (p, int);
2395:
2396: /* If this kind of value comes back in memory,
2397: decide where in memory it should come back. */
2398: if (aggregate_value_p (type_for_mode (outmode, 0)))
2399: {
2400: #ifdef PCC_STATIC_STRUCT_RETURN
2401: rtx pointer_reg
2402: = hard_function_value (build_pointer_type (type_for_mode (outmode, 0)),
2403: 0);
2404: mem_value = gen_rtx (MEM, outmode, pointer_reg);
2405: pcc_struct_value = 1;
2406: if (value == 0)
2407: value = gen_reg_rtx (outmode);
2408: #else /* not PCC_STATIC_STRUCT_RETURN */
2409: struct_value_size = GET_MODE_SIZE (outmode);
2410: if (value != 0 && GET_CODE (value) == MEM)
2411: mem_value = value;
2412: else
2413: mem_value = assign_stack_temp (outmode, GET_MODE_SIZE (outmode), 0);
2414: #endif
2415: }
2416:
2417: /* ??? Unfinished: must pass the memory address as an argument. */
2418:
2419: /* Copy all the libcall-arguments out of the varargs data
2420: and into a vector ARGVEC.
2421:
2422: Compute how to pass each argument. We only support a very small subset
2423: of the full argument passing conventions to limit complexity here since
2424: library functions shouldn't have many args. */
2425:
2426: argvec = (struct arg *) alloca ((nargs + 1) * sizeof (struct arg));
2427:
2428: INIT_CUMULATIVE_ARGS (args_so_far, NULL_TREE, fun);
2429:
2430: args_size.constant = 0;
2431: args_size.var = 0;
2432:
2433: count = 0;
2434:
2435: push_temp_slots ();
2436:
2437: /* If there's a structure value address to be passed,
2438: either pass it in the special place, or pass it as an extra argument. */
2439: if (mem_value && struct_value_rtx == 0 && ! pcc_struct_value)
2440: {
2441: rtx addr = XEXP (mem_value, 0);
2442: nargs++;
2443:
2444: /* Make sure it is a reasonable operand for a move or push insn. */
2445: if (GET_CODE (addr) != REG && GET_CODE (addr) != MEM
2446: && ! (CONSTANT_P (addr) && LEGITIMATE_CONSTANT_P (addr)))
2447: addr = force_operand (addr, NULL_RTX);
2448:
2449: argvec[count].value = addr;
2450: argvec[count].mode = Pmode;
2451: argvec[count].partial = 0;
2452:
2453: argvec[count].reg = FUNCTION_ARG (args_so_far, Pmode, NULL_TREE, 1);
2454: #ifdef FUNCTION_ARG_PARTIAL_NREGS
2455: if (FUNCTION_ARG_PARTIAL_NREGS (args_so_far, Pmode, NULL_TREE, 1))
2456: abort ();
2457: #endif
2458:
2459: locate_and_pad_parm (Pmode, NULL_TREE,
2460: argvec[count].reg && argvec[count].partial == 0,
2461: NULL_TREE, &args_size, &argvec[count].offset,
2462: &argvec[count].size);
2463:
2464:
2465: if (argvec[count].reg == 0 || argvec[count].partial != 0
2466: #ifdef REG_PARM_STACK_SPACE
2467: || 1
2468: #endif
2469: )
2470: args_size.constant += argvec[count].size.constant;
2471:
2472: FUNCTION_ARG_ADVANCE (args_so_far, Pmode, (tree)0, 1);
2473:
2474: count++;
2475: }
2476:
2477: for (; count < nargs; count++)
2478: {
2479: rtx val = va_arg (p, rtx);
2480: enum machine_mode mode = va_arg (p, enum machine_mode);
2481:
2482: /* We cannot convert the arg value to the mode the library wants here;
2483: must do it earlier where we know the signedness of the arg. */
2484: if (mode == BLKmode
2485: || (GET_MODE (val) != mode && GET_MODE (val) != VOIDmode))
2486: abort ();
2487:
2488: /* On some machines, there's no way to pass a float to a library fcn.
2489: Pass it as a double instead. */
2490: #ifdef LIBGCC_NEEDS_DOUBLE
2491: if (LIBGCC_NEEDS_DOUBLE && mode == SFmode)
2492: val = convert_to_mode (DFmode, val, 0), mode = DFmode;
2493: #endif
2494:
2495: /* There's no need to call protect_from_queue, because
2496: either emit_move_insn or emit_push_insn will do that. */
2497:
2498: /* Make sure it is a reasonable operand for a move or push insn. */
2499: if (GET_CODE (val) != REG && GET_CODE (val) != MEM
2500: && ! (CONSTANT_P (val) && LEGITIMATE_CONSTANT_P (val)))
2501: val = force_operand (val, NULL_RTX);
2502:
2503: #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
2504: if (FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, mode, NULL_TREE, 1))
2505: {
2506: /* We do not support FUNCTION_ARG_CALLEE_COPIES here since it can
2507: be viewed as just an efficiency improvement. */
2508: rtx slot = assign_stack_temp (mode, GET_MODE_SIZE (mode), 0);
2509: emit_move_insn (slot, val);
2510: val = XEXP (slot, 0);
2511: mode = Pmode;
2512: }
2513: #endif
2514:
2515: argvec[count].value = val;
2516: argvec[count].mode = mode;
2517:
2518: argvec[count].reg = FUNCTION_ARG (args_so_far, mode, NULL_TREE, 1);
2519: if (argvec[count].reg && GET_CODE (argvec[count].reg) == EXPR_LIST)
2520: abort ();
2521: #ifdef FUNCTION_ARG_PARTIAL_NREGS
2522: argvec[count].partial
2523: = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, mode, NULL_TREE, 1);
2524: #else
2525: argvec[count].partial = 0;
2526: #endif
2527:
2528: locate_and_pad_parm (mode, NULL_TREE,
2529: argvec[count].reg && argvec[count].partial == 0,
2530: NULL_TREE, &args_size, &argvec[count].offset,
2531: &argvec[count].size);
2532:
2533: if (argvec[count].size.var)
2534: abort ();
2535:
2536: #ifndef REG_PARM_STACK_SPACE
2537: if (argvec[count].partial)
2538: argvec[count].size.constant -= argvec[count].partial * UNITS_PER_WORD;
2539: #endif
2540:
2541: if (argvec[count].reg == 0 || argvec[count].partial != 0
2542: #ifdef REG_PARM_STACK_SPACE
2543: || 1
2544: #endif
2545: )
2546: args_size.constant += argvec[count].size.constant;
2547:
2548: #ifdef ACCUMULATE_OUTGOING_ARGS
2549: /* If this arg is actually passed on the stack, it might be
2550: clobbering something we already put there (this library call might
2551: be inside the evaluation of an argument to a function whose call
2552: requires the stack). This will only occur when the library call
2553: has sufficient args to run out of argument registers. Abort in
2554: this case; if this ever occurs, code must be added to save and
2555: restore the arg slot. */
2556:
2557: if (argvec[count].reg == 0 || argvec[count].partial != 0)
2558: abort ();
2559: #endif
2560:
2561: FUNCTION_ARG_ADVANCE (args_so_far, mode, (tree)0, 1);
2562: }
2563: va_end (p);
2564:
2565: /* If this machine requires an external definition for library
2566: functions, write one out. */
2567: assemble_external_libcall (fun);
2568:
2569: original_args_size = args_size;
2570: #ifdef STACK_BOUNDARY
2571: args_size.constant = (((args_size.constant + (STACK_BYTES - 1))
2572: / STACK_BYTES) * STACK_BYTES);
2573: #endif
2574:
2575: #ifdef REG_PARM_STACK_SPACE
2576: args_size.constant = MAX (args_size.constant,
2577: REG_PARM_STACK_SPACE (NULL_TREE));
2578: #ifndef OUTGOING_REG_PARM_STACK_SPACE
2579: args_size.constant -= REG_PARM_STACK_SPACE (NULL_TREE);
2580: #endif
2581: #endif
2582:
2583: #ifdef ACCUMULATE_OUTGOING_ARGS
2584: if (args_size.constant > current_function_outgoing_args_size)
2585: current_function_outgoing_args_size = args_size.constant;
2586: args_size.constant = 0;
2587: #endif
2588:
2589: #ifndef PUSH_ROUNDING
2590: argblock = push_block (GEN_INT (args_size.constant), 0, 0);
2591: #endif
2592:
2593: #ifdef PUSH_ARGS_REVERSED
2594: #ifdef STACK_BOUNDARY
2595: /* If we push args individually in reverse order, perform stack alignment
2596: before the first push (the last arg). */
2597: if (argblock == 0)
2598: anti_adjust_stack (GEN_INT (args_size.constant
2599: - original_args_size.constant));
2600: #endif
2601: #endif
2602:
2603: #ifdef PUSH_ARGS_REVERSED
2604: inc = -1;
2605: argnum = nargs - 1;
2606: #else
2607: inc = 1;
2608: argnum = 0;
2609: #endif
2610:
2611: /* Push the args that need to be pushed. */
2612:
2613: for (count = 0; count < nargs; count++, argnum += inc)
2614: {
2615: register enum machine_mode mode = argvec[argnum].mode;
2616: register rtx val = argvec[argnum].value;
2617: rtx reg = argvec[argnum].reg;
2618: int partial = argvec[argnum].partial;
2619:
2620: if (! (reg != 0 && partial == 0))
2621: emit_push_insn (val, mode, NULL_TREE, NULL_RTX, 0, partial, reg, 0,
2622: argblock, GEN_INT (argvec[count].offset.constant));
2623: NO_DEFER_POP;
2624: }
2625:
2626: #ifndef PUSH_ARGS_REVERSED
2627: #ifdef STACK_BOUNDARY
2628: /* If we pushed args in forward order, perform stack alignment
2629: after pushing the last arg. */
2630: if (argblock == 0)
2631: anti_adjust_stack (GEN_INT (args_size.constant
2632: - original_args_size.constant));
2633: #endif
2634: #endif
2635:
2636: #ifdef PUSH_ARGS_REVERSED
2637: argnum = nargs - 1;
2638: #else
2639: argnum = 0;
2640: #endif
2641:
2642: /* Now load any reg parms into their regs. */
2643:
2644: for (count = 0; count < nargs; count++, argnum += inc)
2645: {
2646: register enum machine_mode mode = argvec[argnum].mode;
2647: register rtx val = argvec[argnum].value;
2648: rtx reg = argvec[argnum].reg;
2649: int partial = argvec[argnum].partial;
2650:
2651: if (reg != 0 && partial == 0)
2652: emit_move_insn (reg, val);
2653: NO_DEFER_POP;
2654: }
2655:
2656: #if 0
2657: /* For version 1.37, try deleting this entirely. */
2658: if (! no_queue)
2659: emit_queue ();
2660: #endif
2661:
2662: /* Any regs containing parms remain in use through the call. */
2663: start_sequence ();
2664: for (count = 0; count < nargs; count++)
2665: if (argvec[count].reg != 0)
2666: emit_insn (gen_rtx (USE, VOIDmode, argvec[count].reg));
2667:
2668: use_insns = get_insns ();
2669: end_sequence ();
2670:
2671: /* Pass the function the address in which to return a structure value. */
2672: if (mem_value != 0 && struct_value_rtx != 0 && ! pcc_struct_value)
2673: {
2674: emit_move_insn (struct_value_rtx,
2675: force_reg (Pmode,
2676: force_operand (XEXP (mem_value, 0),
2677: NULL_RTX)));
2678: if (GET_CODE (struct_value_rtx) == REG)
2679: {
2680: push_to_sequence (use_insns);
2681: emit_insn (gen_rtx (USE, VOIDmode, struct_value_rtx));
2682: use_insns = get_insns ();
2683: end_sequence ();
2684: }
2685: }
2686:
2687: fun = prepare_call_address (fun, NULL_TREE, &use_insns);
2688:
2689: /* Don't allow popping to be deferred, since then
2690: cse'ing of library calls could delete a call and leave the pop. */
2691: NO_DEFER_POP;
2692:
2693: /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
2694: will set inhibit_defer_pop to that value. */
2695:
2696: emit_call_1 (fun, get_identifier (XSTR (orgfun, 0)), args_size.constant,
2697: struct_value_size,
2698: FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
2699: (outmode != VOIDmode && mem_value == 0
2700: ? hard_libcall_value (outmode) : NULL_RTX),
2701: old_inhibit_defer_pop + 1, use_insns, no_queue);
2702:
2703: /* Now restore inhibit_defer_pop to its actual original value. */
2704: OK_DEFER_POP;
2705:
2706: pop_temp_slots ();
2707:
2708: /* Copy the value to the right place. */
2709: if (outmode != VOIDmode)
2710: {
2711: if (mem_value)
2712: {
2713: if (value == 0)
2714: value = mem_value;
2715: if (value != mem_value)
2716: emit_move_insn (value, mem_value);
2717: }
2718: else if (value != 0)
2719: emit_move_insn (value, hard_libcall_value (outmode));
2720: else
2721: value = hard_libcall_value (outmode);
2722: }
2723:
2724: return value;
2725: }
2726:
2727: #if 0
2728: /* Return an rtx which represents a suitable home on the stack
2729: given TYPE, the type of the argument looking for a home.
2730: This is called only for BLKmode arguments.
2731:
2732: SIZE is the size needed for this target.
2733: ARGS_ADDR is the address of the bottom of the argument block for this call.
2734: OFFSET describes this parameter's offset into ARGS_ADDR. It is meaningless
2735: if this machine uses push insns. */
2736:
2737: static rtx
2738: target_for_arg (type, size, args_addr, offset)
2739: tree type;
2740: rtx size;
2741: rtx args_addr;
2742: struct args_size offset;
2743: {
2744: rtx target;
2745: rtx offset_rtx = ARGS_SIZE_RTX (offset);
2746:
2747: /* We do not call memory_address if possible,
2748: because we want to address as close to the stack
2749: as possible. For non-variable sized arguments,
2750: this will be stack-pointer relative addressing. */
2751: if (GET_CODE (offset_rtx) == CONST_INT)
2752: target = plus_constant (args_addr, INTVAL (offset_rtx));
2753: else
2754: {
2755: /* I have no idea how to guarantee that this
2756: will work in the presence of register parameters. */
2757: target = gen_rtx (PLUS, Pmode, args_addr, offset_rtx);
2758: target = memory_address (QImode, target);
2759: }
2760:
2761: return gen_rtx (MEM, BLKmode, target);
2762: }
2763: #endif
2764:
2765: /* Store a single argument for a function call
2766: into the register or memory area where it must be passed.
2767: *ARG describes the argument value and where to pass it.
2768:
2769: ARGBLOCK is the address of the stack-block for all the arguments,
2770: or 0 on a machine where arguments are pushed individually.
2771:
2772: MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
2773: so must be careful about how the stack is used.
2774:
2775: VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
2776: argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
2777: that we need not worry about saving and restoring the stack.
2778:
2779: FNDECL is the declaration of the function we are calling. */
2780:
2781: static void
2782: store_one_arg (arg, argblock, may_be_alloca, variable_size, fndecl,
2783: reg_parm_stack_space)
2784: struct arg_data *arg;
2785: rtx argblock;
2786: int may_be_alloca;
2787: int variable_size;
2788: tree fndecl;
2789: int reg_parm_stack_space;
2790: {
2791: register tree pval = arg->tree_value;
2792: rtx reg = 0;
2793: int partial = 0;
2794: int used = 0;
2795: int i, lower_bound, upper_bound;
2796:
2797: if (TREE_CODE (pval) == ERROR_MARK)
2798: return;
2799:
2800: #ifdef ACCUMULATE_OUTGOING_ARGS
2801: /* If this is being stored into a pre-allocated, fixed-size, stack area,
2802: save any previous data at that location. */
2803: if (argblock && ! variable_size && arg->stack)
2804: {
2805: #ifdef ARGS_GROW_DOWNWARD
2806: /* stack_slot is negative, but we want to index stack_usage_map */
2807: /* with positive values. */
2808: if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2809: upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
2810: else
2811: abort ();
2812:
2813: lower_bound = upper_bound - arg->size.constant;
2814: #else
2815: if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
2816: lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
2817: else
2818: lower_bound = 0;
2819:
2820: upper_bound = lower_bound + arg->size.constant;
2821: #endif
2822:
2823: for (i = lower_bound; i < upper_bound; i++)
2824: if (stack_usage_map[i]
2825: #ifdef REG_PARM_STACK_SPACE
2826: /* Don't store things in the fixed argument area at this point;
2827: it has already been saved. */
2828: && i > reg_parm_stack_space
2829: #endif
2830: )
2831: break;
2832:
2833: if (i != upper_bound)
2834: {
2835: /* We need to make a save area. See what mode we can make it. */
2836: enum machine_mode save_mode
2837: = mode_for_size (arg->size.constant * BITS_PER_UNIT, MODE_INT, 1);
2838: rtx stack_area
2839: = gen_rtx (MEM, save_mode,
2840: memory_address (save_mode, XEXP (arg->stack_slot, 0)));
2841:
2842: if (save_mode == BLKmode)
2843: {
2844: arg->save_area = assign_stack_temp (BLKmode,
2845: arg->size.constant, 1);
2846: emit_block_move (validize_mem (arg->save_area), stack_area,
2847: GEN_INT (arg->size.constant),
2848: PARM_BOUNDARY / BITS_PER_UNIT);
2849: }
2850: else
2851: {
2852: arg->save_area = gen_reg_rtx (save_mode);
2853: emit_move_insn (arg->save_area, stack_area);
2854: }
2855: }
2856: }
2857: #endif
2858:
2859: /* If this isn't going to be placed on both the stack and in registers,
2860: set up the register and number of words. */
2861: if (! arg->pass_on_stack)
2862: reg = arg->reg, partial = arg->partial;
2863:
2864: if (reg != 0 && partial == 0)
2865: /* Being passed entirely in a register. We shouldn't be called in
2866: this case. */
2867: abort ();
2868:
2869: #ifdef STRICT_ALIGNMENT
2870: /* If this arg needs special alignment, don't load the registers
2871: here. */
2872: if (arg->n_aligned_regs != 0)
2873: reg = 0;
2874: #endif
2875:
2876: /* If this is being partially passed in a register, but multiple locations
2877: are specified, we assume that the one partially used is the one that is
2878: listed first. */
2879: if (reg && GET_CODE (reg) == EXPR_LIST)
2880: reg = XEXP (reg, 0);
2881:
2882: /* If this is being passed partially in a register, we can't evaluate
2883: it directly into its stack slot. Otherwise, we can. */
2884: if (arg->value == 0)
2885: {
2886: #ifdef ACCUMULATE_OUTGOING_ARGS
2887: /* stack_arg_under_construction is nonzero if a function argument is
2888: being evaluated directly into the outgoing argument list and
2889: expand_call must take special action to preserve the argument list
2890: if it is called recursively.
2891:
2892: For scalar function arguments stack_usage_map is sufficient to
2893: determine which stack slots must be saved and restored. Scalar
2894: arguments in general have pass_on_stack == 0.
2895:
2896: If this argument is initialized by a function which takes the
2897: address of the argument (a C++ constructor or a C function
2898: returning a BLKmode structure), then stack_usage_map is
2899: insufficient and expand_call must push the stack around the
2900: function call. Such arguments have pass_on_stack == 1.
2901:
2902: Note that it is always safe to set stack_arg_under_construction,
2903: but this generates suboptimal code if set when not needed. */
2904:
2905: if (arg->pass_on_stack)
2906: stack_arg_under_construction++;
2907: #endif
2908: arg->value = expand_expr (pval,
2909: (partial
2910: || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
2911: ? NULL_RTX : arg->stack,
2912: VOIDmode, 0);
2913:
2914: /* If we are promoting object (or for any other reason) the mode
2915: doesn't agree, convert the mode. */
2916:
2917: if (GET_MODE (arg->value) != VOIDmode
2918: && GET_MODE (arg->value) != arg->mode)
2919: arg->value = convert_to_mode (arg->mode, arg->value, arg->unsignedp);
2920:
2921: #ifdef ACCUMULATE_OUTGOING_ARGS
2922: if (arg->pass_on_stack)
2923: stack_arg_under_construction--;
2924: #endif
2925: }
2926:
2927: /* Don't allow anything left on stack from computation
2928: of argument to alloca. */
2929: if (may_be_alloca)
2930: do_pending_stack_adjust ();
2931:
2932: if (arg->value == arg->stack)
2933: /* If the value is already in the stack slot, we are done. */
2934: ;
2935: else if (arg->mode != BLKmode)
2936: {
2937: register int size;
2938:
2939: /* Argument is a scalar, not entirely passed in registers.
2940: (If part is passed in registers, arg->partial says how much
2941: and emit_push_insn will take care of putting it there.)
2942:
2943: Push it, and if its size is less than the
2944: amount of space allocated to it,
2945: also bump stack pointer by the additional space.
2946: Note that in C the default argument promotions
2947: will prevent such mismatches. */
2948:
2949: size = GET_MODE_SIZE (arg->mode);
2950: /* Compute how much space the push instruction will push.
2951: On many machines, pushing a byte will advance the stack
2952: pointer by a halfword. */
2953: #ifdef PUSH_ROUNDING
2954: size = PUSH_ROUNDING (size);
2955: #endif
2956: used = size;
2957:
2958: /* Compute how much space the argument should get:
2959: round up to a multiple of the alignment for arguments. */
2960: if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
2961: used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
2962: / (PARM_BOUNDARY / BITS_PER_UNIT))
2963: * (PARM_BOUNDARY / BITS_PER_UNIT));
2964:
2965: /* This isn't already where we want it on the stack, so put it there.
2966: This can either be done with push or copy insns. */
2967: emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
2968: 0, partial, reg, used - size,
2969: argblock, ARGS_SIZE_RTX (arg->offset));
2970: }
2971: else
2972: {
2973: /* BLKmode, at least partly to be pushed. */
2974:
2975: register int excess;
2976: rtx size_rtx;
2977:
2978: /* Pushing a nonscalar.
2979: If part is passed in registers, PARTIAL says how much
2980: and emit_push_insn will take care of putting it there. */
2981:
2982: /* Round its size up to a multiple
2983: of the allocation unit for arguments. */
2984:
2985: if (arg->size.var != 0)
2986: {
2987: excess = 0;
2988: size_rtx = ARGS_SIZE_RTX (arg->size);
2989: }
2990: else
2991: {
2992: /* PUSH_ROUNDING has no effect on us, because
2993: emit_push_insn for BLKmode is careful to avoid it. */
2994: excess = (arg->size.constant - int_size_in_bytes (TREE_TYPE (pval))
2995: + partial * UNITS_PER_WORD);
2996: size_rtx = expr_size (pval);
2997: }
2998:
2999: emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
3000: TYPE_ALIGN (TREE_TYPE (pval)) / BITS_PER_UNIT, partial,
3001: reg, excess, argblock, ARGS_SIZE_RTX (arg->offset));
3002: }
3003:
3004:
3005: /* Unless this is a partially-in-register argument, the argument is now
3006: in the stack.
3007:
3008: ??? Note that this can change arg->value from arg->stack to
3009: arg->stack_slot and it matters when they are not the same.
3010: It isn't totally clear that this is correct in all cases. */
3011: if (partial == 0)
3012: arg->value = arg->stack_slot;
3013:
3014: /* Once we have pushed something, pops can't safely
3015: be deferred during the rest of the arguments. */
3016: NO_DEFER_POP;
3017:
3018: /* ANSI doesn't require a sequence point here,
3019: but PCC has one, so this will avoid some problems. */
3020: emit_queue ();
3021:
3022: /* Free any temporary slots made in processing this argument. */
3023: free_temp_slots ();
3024:
3025: #ifdef ACCUMULATE_OUTGOING_ARGS
3026: /* Now mark the segment we just used. */
3027: if (argblock && ! variable_size && arg->stack)
3028: for (i = lower_bound; i < upper_bound; i++)
3029: stack_usage_map[i] = 1;
3030: #endif
3031: }
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