1 /* Register Transfer Language (RTL) definitions for GNU C-Compiler
2 Copyright (C) 1987, 91-95, 1996 Free Software Foundation, Inc.
4 This file is part of GNU CC.
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)
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.
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, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
24 #undef FFS /* Some systems predefine this symbol; don't let it interfere. */
25 #undef FLOAT /* Likewise. */
26 #undef ABS /* Likewise. */
27 #undef PC /* Likewise. */
33 /* Register Transfer Language EXPRESSIONS CODES */
35 #define RTX_CODE enum rtx_code
38 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) ENUM ,
39 #include "rtl.def" /* rtl expressions are documented here */
42 LAST_AND_UNUSED_RTX_CODE}; /* A convenient way to get a value for
44 Assumes default enum value assignment. */
46 #define NUM_RTX_CODE ((int)LAST_AND_UNUSED_RTX_CODE)
47 /* The cast here, saves many elsewhere. */
49 extern int rtx_length[];
50 #define GET_RTX_LENGTH(CODE) (rtx_length[(int) (CODE)])
52 extern char *rtx_name[];
53 #define GET_RTX_NAME(CODE) (rtx_name[(int) (CODE)])
55 extern char *rtx_format[];
56 #define GET_RTX_FORMAT(CODE) (rtx_format[(int) (CODE)])
58 extern char rtx_class[];
59 #define GET_RTX_CLASS(CODE) (rtx_class[(int) (CODE)])
61 /* Common union for an element of an rtx. */
63 typedef union rtunion_def
69 struct rtvec_def *rtvec;
70 enum machine_mode rttype;
73 /* RTL expression ("rtx"). */
75 typedef struct rtx_def
77 #ifdef ONLY_INT_FIELDS
79 unsigned int code : 16;
84 /* The kind of expression this is. */
85 enum rtx_code code : 16;
87 /* The kind of value the expression has. */
88 #ifdef ONLY_INT_FIELDS
91 enum machine_mode mode : 8;
93 /* 1 in an INSN if it can alter flow of control
94 within this function. Not yet used! */
95 unsigned int jump : 1;
96 /* 1 in an INSN if it can call another function. Not yet used! */
97 unsigned int call : 1;
98 /* 1 in a MEM or REG if value of this expression will never change
99 during the current function, even though it is not
101 1 in a SUBREG if it is from a promoted variable that is unsigned.
102 1 in a SYMBOL_REF if it addresses something in the per-function
104 1 in a CALL_INSN if it is a const call.
105 1 in a JUMP_INSN if it is a branch that should be annulled. Valid from
106 reorg until end of compilation; cleared before used. */
107 unsigned int unchanging : 1;
108 /* 1 in a MEM expression if contents of memory are volatile.
109 1 in an INSN, CALL_INSN, JUMP_INSN, CODE_LABEL or BARRIER
111 1 in a REG expression if corresponds to a variable declared by the user.
112 0 for an internally generated temporary.
113 In a SYMBOL_REF, this flag is used for machine-specific purposes.
114 In a LABEL_REF or in a REG_LABEL note, this is LABEL_REF_NONLOCAL_P. */
115 unsigned int volatil : 1;
116 /* 1 in a MEM referring to a field of a structure (not a union!).
117 0 if the MEM was a variable or the result of a * operator in C;
118 1 if it was the result of a . or -> operator (on a struct) in C.
119 1 in a REG if the register is used only in exit code a loop.
120 1 in a SUBREG expression if was generated from a variable with a
122 1 in a CODE_LABEL if the label is used for nonlocal gotos
123 and must not be deleted even if its count is zero.
124 1 in a LABEL_REF if this is a reference to a label outside the
126 1 in an INSN, JUMP_INSN, or CALL_INSN if this insn must be scheduled
127 together with the preceding insn. Valid only within sched.
128 1 in an INSN, JUMP_INSN, or CALL_INSN if insn is in a delay slot and
129 from the target of a branch. Valid from reorg until end of compilation;
130 cleared before used. */
131 unsigned int in_struct : 1;
132 /* 1 if this rtx is used. This is used for copying shared structure.
133 See `unshare_all_rtl'.
134 In a REG, this is not needed for that purpose, and used instead
135 in `leaf_renumber_regs_insn'.
136 In a SYMBOL_REF, means that emit_library_call
137 has used it as the function. */
138 unsigned int used : 1;
139 /* Nonzero if this rtx came from procedure integration.
140 In a REG, nonzero means this reg refers to the return value
141 of the current function. */
142 unsigned integrated : 1;
143 /* Nonzero if this rtx is related to the call frame, either changing how
144 we compute the frame address or saving and restoring registers in
145 the prologue and epilogue. */
146 unsigned frame_related : 1;
147 /* The first element of the operands of this rtx.
148 The number of operands and their types are controlled
149 by the `code' field, according to rtl.def. */
153 #include "gansidecl.h"
155 #define NULL_RTX (rtx) 0
157 /* Define macros to access the `code' field of the rtx. */
159 #ifdef SHORT_ENUM_BUG
160 #define GET_CODE(RTX) ((enum rtx_code) ((RTX)->code))
161 #define PUT_CODE(RTX, CODE) ((RTX)->code = ((short) (CODE)))
163 #define GET_CODE(RTX) ((RTX)->code)
164 #define PUT_CODE(RTX, CODE) ((RTX)->code = (CODE))
167 #define GET_MODE(RTX) ((RTX)->mode)
168 #define PUT_MODE(RTX, MODE) ((RTX)->mode = (MODE))
170 #define RTX_INTEGRATED_P(RTX) ((RTX)->integrated)
171 #define RTX_UNCHANGING_P(RTX) ((RTX)->unchanging)
172 #define RTX_FRAME_RELATED_P(RTX) ((RTX)->frame_related)
174 /* RTL vector. These appear inside RTX's when there is a need
175 for a variable number of things. The principle use is inside
176 PARALLEL expressions. */
178 typedef struct rtvec_def{
179 unsigned num_elem; /* number of elements */
183 #define NULL_RTVEC (rtvec) 0
185 #define GET_NUM_ELEM(RTVEC) ((RTVEC)->num_elem)
186 #define PUT_NUM_ELEM(RTVEC, NUM) ((RTVEC)->num_elem = (unsigned) NUM)
188 #define RTVEC_ELT(RTVEC, I) ((RTVEC)->elem[(I)].rtx)
190 /* 1 if X is a REG. */
192 #define REG_P(X) (GET_CODE (X) == REG)
194 /* 1 if X is a constant value that is an integer. */
196 #define CONSTANT_P(X) \
197 (GET_CODE (X) == LABEL_REF || GET_CODE (X) == SYMBOL_REF \
198 || GET_CODE (X) == CONST_INT || GET_CODE (X) == CONST_DOUBLE \
199 || GET_CODE (X) == CONST || GET_CODE (X) == HIGH)
201 /* General accessor macros for accessing the fields of an rtx. */
203 #define XEXP(RTX, N) ((RTX)->fld[N].rtx)
204 #define XINT(RTX, N) ((RTX)->fld[N].rtint)
205 #define XWINT(RTX, N) ((RTX)->fld[N].rtwint)
206 #define XSTR(RTX, N) ((RTX)->fld[N].rtstr)
207 #define XVEC(RTX, N) ((RTX)->fld[N].rtvec)
208 #define XVECLEN(RTX, N) ((RTX)->fld[N].rtvec->num_elem)
209 #define XVECEXP(RTX,N,M)((RTX)->fld[N].rtvec->elem[M].rtx)
211 /* ACCESS MACROS for particular fields of insns. */
213 /* Holds a unique number for each insn.
214 These are not necessarily sequentially increasing. */
215 #define INSN_UID(INSN) ((INSN)->fld[0].rtint)
217 /* Chain insns together in sequence. */
218 #define PREV_INSN(INSN) ((INSN)->fld[1].rtx)
219 #define NEXT_INSN(INSN) ((INSN)->fld[2].rtx)
221 /* The body of an insn. */
222 #define PATTERN(INSN) ((INSN)->fld[3].rtx)
224 /* Code number of instruction, from when it was recognized.
225 -1 means this instruction has not been recognized yet. */
226 #define INSN_CODE(INSN) ((INSN)->fld[4].rtint)
228 /* Set up in flow.c; empty before then.
229 Holds a chain of INSN_LIST rtx's whose first operands point at
230 previous insns with direct data-flow connections to this one.
231 That means that those insns set variables whose next use is in this insn.
232 They are always in the same basic block as this insn. */
233 #define LOG_LINKS(INSN) ((INSN)->fld[5].rtx)
235 /* 1 if insn has been deleted. */
236 #define INSN_DELETED_P(INSN) ((INSN)->volatil)
238 /* 1 if insn is a call to a const function. */
239 #define CONST_CALL_P(INSN) ((INSN)->unchanging)
241 /* 1 if insn is a branch that should not unconditionally execute its
242 delay slots, i.e., it is an annulled branch. */
243 #define INSN_ANNULLED_BRANCH_P(INSN) ((INSN)->unchanging)
245 /* 1 if insn is in a delay slot and is from the target of the branch. If
246 the branch insn has INSN_ANNULLED_BRANCH_P set, this insn should only be
247 executed if the branch is taken. For annulled branches with this bit
248 clear, the insn should be executed only if the branch is not taken. */
249 #define INSN_FROM_TARGET_P(INSN) ((INSN)->in_struct)
251 /* Holds a list of notes on what this insn does to various REGs.
252 It is a chain of EXPR_LIST rtx's, where the second operand
253 is the chain pointer and the first operand is the REG being described.
254 The mode field of the EXPR_LIST contains not a real machine mode
255 but a value that says what this note says about the REG:
256 REG_DEAD means that the value in REG dies in this insn (i.e., it is
257 not needed past this insn). If REG is set in this insn, the REG_DEAD
258 note may, but need not, be omitted.
259 REG_INC means that the REG is autoincremented or autodecremented.
260 REG_EQUIV describes the insn as a whole; it says that the
261 insn sets a register to a constant value or to be equivalent to
262 a memory address. If the
263 register is spilled to the stack then the constant value
264 should be substituted for it. The contents of the REG_EQUIV
265 is the constant value or memory address, which may be different
266 from the source of the SET although it has the same value.
267 REG_EQUAL is like REG_EQUIV except that the destination
268 is only momentarily equal to the specified rtx. Therefore, it
269 cannot be used for substitution; but it can be used for cse.
270 REG_RETVAL means that this insn copies the return-value of
271 a library call out of the hard reg for return values. This note
272 is actually an INSN_LIST and it points to the first insn involved
273 in setting up arguments for the call. flow.c uses this to delete
274 the entire library call when its result is dead.
275 REG_LIBCALL is the inverse of REG_RETVAL: it goes on the first insn
276 of the library call and points at the one that has the REG_RETVAL.
277 REG_WAS_0 says that the register set in this insn held 0 before the insn.
278 The contents of the note is the insn that stored the 0.
279 If that insn is deleted or patched to a NOTE, the REG_WAS_0 is inoperative.
280 The REG_WAS_0 note is actually an INSN_LIST, not an EXPR_LIST.
281 REG_NONNEG means that the register is always nonnegative during
282 the containing loop. This is used in branches so that decrement and
283 branch instructions terminating on zero can be matched. There must be
284 an insn pattern in the md file named `decrement_and_branch_until_zero'
285 or else this will never be added to any instructions.
286 REG_NO_CONFLICT means there is no conflict *after this insn*
287 between the register in the note and the destination of this insn.
288 REG_UNUSED identifies a register set in this insn and never used.
289 REG_CC_SETTER and REG_CC_USER link a pair of insns that set and use
290 CC0, respectively. Normally, these are required to be consecutive insns,
291 but we permit putting a cc0-setting insn in the delay slot of a branch
292 as long as only one copy of the insn exists. In that case, these notes
293 point from one to the other to allow code generation to determine what
294 any require information and to properly update CC_STATUS.
295 REG_LABEL points to a CODE_LABEL. Used by non-JUMP_INSNs to
296 say that the CODE_LABEL contained in the REG_LABEL note is used
298 REG_DEP_ANTI is used in LOG_LINKS which represent anti (write after read)
299 dependencies. REG_DEP_OUTPUT is used in LOG_LINKS which represent output
300 (write after write) dependencies. Data dependencies, which are the only
301 type of LOG_LINK created by flow, are represented by a 0 reg note kind. */
303 #define REG_NOTES(INSN) ((INSN)->fld[6].rtx)
305 /* Don't forget to change reg_note_name in rtl.c. */
306 enum reg_note { REG_DEAD = 1, REG_INC = 2, REG_EQUIV = 3, REG_WAS_0 = 4,
307 REG_EQUAL = 5, REG_RETVAL = 6, REG_LIBCALL = 7,
308 REG_NONNEG = 8, REG_NO_CONFLICT = 9, REG_UNUSED = 10,
309 REG_CC_SETTER = 11, REG_CC_USER = 12, REG_LABEL = 13,
310 REG_DEP_ANTI = 14, REG_DEP_OUTPUT = 15 };
312 /* Define macros to extract and insert the reg-note kind in an EXPR_LIST. */
313 #define REG_NOTE_KIND(LINK) ((enum reg_note) GET_MODE (LINK))
314 #define PUT_REG_NOTE_KIND(LINK,KIND) PUT_MODE(LINK, (enum machine_mode) (KIND))
316 /* Names for REG_NOTE's in EXPR_LIST insn's. */
318 extern char *reg_note_name[];
319 #define GET_REG_NOTE_NAME(MODE) (reg_note_name[(int) (MODE)])
321 /* This field is only present on CALL_INSNs. It holds a chain of EXPR_LIST of
322 USE and CLOBBER expressions.
323 USE expressions list the registers filled with arguments that
324 are passed to the function.
325 CLOBBER expressions document the registers explicitly clobbered
327 Pseudo registers can not be mentioned in this list. */
328 #define CALL_INSN_FUNCTION_USAGE(INSN) ((INSN)->fld[7].rtx)
330 /* The label-number of a code-label. The assembler label
331 is made from `L' and the label-number printed in decimal.
332 Label numbers are unique in a compilation. */
333 #define CODE_LABEL_NUMBER(INSN) ((INSN)->fld[3].rtint)
335 #define LINE_NUMBER NOTE
337 /* In a NOTE that is a line number, this is a string for the file name
338 that the line is in. We use the same field to record block numbers
339 temporarily in NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes.
340 (We avoid lots of casts between ints and pointers if we use a
341 different macro for the bock number.) */
343 #define NOTE_SOURCE_FILE(INSN) ((INSN)->fld[3].rtstr)
344 #define NOTE_BLOCK_NUMBER(INSN) ((INSN)->fld[3].rtint)
346 /* In a NOTE that is a line number, this is the line number.
347 Other kinds of NOTEs are identified by negative numbers here. */
348 #define NOTE_LINE_NUMBER(INSN) ((INSN)->fld[4].rtint)
350 /* Codes that appear in the NOTE_LINE_NUMBER field
351 for kinds of notes that are not line numbers.
353 Notice that we do not try to use zero here for any of
354 the special note codes because sometimes the source line
355 actually can be zero! This happens (for example) when we
356 are generating code for the per-translation-unit constructor
357 and destructor routines for some C++ translation unit.
359 If you should change any of the following values, or if you
360 should add a new value here, don't forget to change the
361 note_insn_name array in rtl.c. */
363 /* This note is used to get rid of an insn
364 when it isn't safe to patch the insn out of the chain. */
365 #define NOTE_INSN_DELETED -1
366 #define NOTE_INSN_BLOCK_BEG -2
367 #define NOTE_INSN_BLOCK_END -3
368 #define NOTE_INSN_LOOP_BEG -4
369 #define NOTE_INSN_LOOP_END -5
370 /* This kind of note is generated at the end of the function body,
371 just before the return insn or return label.
372 In an optimizing compilation it is deleted by the first jump optimization,
373 after enabling that optimizer to determine whether control can fall
374 off the end of the function body without a return statement. */
375 #define NOTE_INSN_FUNCTION_END -6
376 /* This kind of note is generated just after each call to `setjmp', et al. */
377 #define NOTE_INSN_SETJMP -7
378 /* Generated at the place in a loop that `continue' jumps to. */
379 #define NOTE_INSN_LOOP_CONT -8
380 /* Generated at the start of a duplicated exit test. */
381 #define NOTE_INSN_LOOP_VTOP -9
382 /* This marks the point immediately after the last prologue insn. */
383 #define NOTE_INSN_PROLOGUE_END -10
384 /* This marks the point immediately prior to the first epilogue insn. */
385 #define NOTE_INSN_EPILOGUE_BEG -11
386 /* Generated in place of user-declared labels when they are deleted. */
387 #define NOTE_INSN_DELETED_LABEL -12
388 /* This note indicates the start of the real body of the function,
389 i.e. the point just after all of the parms have been moved into
391 #define NOTE_INSN_FUNCTION_BEG -13
392 /* These note where exception handling regions begin and end. */
393 #define NOTE_INSN_EH_REGION_BEG -14
394 #define NOTE_INSN_EH_REGION_END -15
397 #if 0 /* These are not used, and I don't know what they were for. --rms. */
398 #define NOTE_DECL_NAME(INSN) ((INSN)->fld[3].rtstr)
399 #define NOTE_DECL_CODE(INSN) ((INSN)->fld[4].rtint)
400 #define NOTE_DECL_RTL(INSN) ((INSN)->fld[5].rtx)
401 #define NOTE_DECL_IDENTIFIER(INSN) ((INSN)->fld[6].rtint)
402 #define NOTE_DECL_TYPE(INSN) ((INSN)->fld[7].rtint)
405 /* Names for NOTE insn's other than line numbers. */
407 extern char *note_insn_name[];
408 #define GET_NOTE_INSN_NAME(NOTE_CODE) (note_insn_name[-(NOTE_CODE)])
410 /* The name of a label, in case it corresponds to an explicit label
411 in the input source code. */
412 #define LABEL_NAME(LABEL) ((LABEL)->fld[4].rtstr)
414 /* In jump.c, each label contains a count of the number
415 of LABEL_REFs that point at it, so unused labels can be deleted. */
416 #define LABEL_NUSES(LABEL) ((LABEL)->fld[5].rtint)
418 /* The rest is used instead of the above, in a CODE_LABEL,
419 if bytecode is being output.
420 We make the slightly kludgy assumption that a LABEL has enough slots
421 to hold these things. That happens to be true. */
423 /* For static or external objects. */
424 #define BYTECODE_LABEL(X) (XEXP ((X), 0))
426 /* For goto labels inside bytecode functions. */
427 #define BYTECODE_BC_LABEL(X) (*(struct bc_label **) &XEXP ((X), 1))
429 /* In jump.c, each JUMP_INSN can point to a label that it can jump to,
430 so that if the JUMP_INSN is deleted, the label's LABEL_NUSES can
431 be decremented and possibly the label can be deleted. */
432 #define JUMP_LABEL(INSN) ((INSN)->fld[7].rtx)
434 /* Once basic blocks are found in flow.c,
435 each CODE_LABEL starts a chain that goes through
436 all the LABEL_REFs that jump to that label.
437 The chain eventually winds up at the CODE_LABEL; it is circular. */
438 #define LABEL_REFS(LABEL) ((LABEL)->fld[5].rtx)
440 /* This is the field in the LABEL_REF through which the circular chain
441 of references to a particular label is linked.
442 This chain is set up in flow.c. */
444 #define LABEL_NEXTREF(REF) ((REF)->fld[1].rtx)
446 /* Once basic blocks are found in flow.c,
447 Each LABEL_REF points to its containing instruction with this field. */
449 #define CONTAINING_INSN(RTX) ((RTX)->fld[2].rtx)
451 /* For a REG rtx, REGNO extracts the register number. */
453 #define REGNO(RTX) ((RTX)->fld[0].rtint)
455 /* For a REG rtx, REG_FUNCTION_VALUE_P is nonzero if the reg
456 is the current function's return value. */
458 #define REG_FUNCTION_VALUE_P(RTX) ((RTX)->integrated)
460 /* 1 in a REG rtx if it corresponds to a variable declared by the user. */
461 #define REG_USERVAR_P(RTX) ((RTX)->volatil)
463 /* For a CONST_INT rtx, INTVAL extracts the integer. */
465 #define INTVAL(RTX) ((RTX)->fld[0].rtwint)
467 /* For a SUBREG rtx, SUBREG_REG extracts the value we want a subreg of.
468 SUBREG_WORD extracts the word-number. */
470 #define SUBREG_REG(RTX) ((RTX)->fld[0].rtx)
471 #define SUBREG_WORD(RTX) ((RTX)->fld[1].rtint)
473 /* 1 if the REG contained in SUBREG_REG is already known to be
474 sign- or zero-extended from the mode of the SUBREG to the mode of
475 the reg. SUBREG_PROMOTED_UNSIGNED_P gives the signedness of the
478 When used as a LHS, is means that this extension must be done
479 when assigning to SUBREG_REG. */
481 #define SUBREG_PROMOTED_VAR_P(RTX) ((RTX)->in_struct)
482 #define SUBREG_PROMOTED_UNSIGNED_P(RTX) ((RTX)->unchanging)
484 /* Access various components of an ASM_OPERANDS rtx. */
486 #define ASM_OPERANDS_TEMPLATE(RTX) XSTR ((RTX), 0)
487 #define ASM_OPERANDS_OUTPUT_CONSTRAINT(RTX) XSTR ((RTX), 1)
488 #define ASM_OPERANDS_OUTPUT_IDX(RTX) XINT ((RTX), 2)
489 #define ASM_OPERANDS_INPUT_VEC(RTX) XVEC ((RTX), 3)
490 #define ASM_OPERANDS_INPUT_CONSTRAINT_VEC(RTX) XVEC ((RTX), 4)
491 #define ASM_OPERANDS_INPUT(RTX, N) XVECEXP ((RTX), 3, (N))
492 #define ASM_OPERANDS_INPUT_LENGTH(RTX) XVECLEN ((RTX), 3)
493 #define ASM_OPERANDS_INPUT_CONSTRAINT(RTX, N) XSTR (XVECEXP ((RTX), 4, (N)), 0)
494 #define ASM_OPERANDS_INPUT_MODE(RTX, N) GET_MODE (XVECEXP ((RTX), 4, (N)))
495 #define ASM_OPERANDS_SOURCE_FILE(RTX) XSTR ((RTX), 5)
496 #define ASM_OPERANDS_SOURCE_LINE(RTX) XINT ((RTX), 6)
498 /* For a MEM rtx, 1 if it's a volatile reference.
499 Also in an ASM_OPERANDS rtx. */
500 #define MEM_VOLATILE_P(RTX) ((RTX)->volatil)
502 /* For a MEM rtx, 1 if it refers to a structure or union component. */
503 #define MEM_IN_STRUCT_P(RTX) ((RTX)->in_struct)
505 /* For a LABEL_REF, 1 means that this reference is to a label outside the
506 loop containing the reference. */
507 #define LABEL_OUTSIDE_LOOP_P(RTX) ((RTX)->in_struct)
509 /* For a LABEL_REF, 1 means it is for a nonlocal label. */
510 /* Likewise in an EXPR_LIST for a REG_LABEL note. */
511 #define LABEL_REF_NONLOCAL_P(RTX) ((RTX)->volatil)
513 /* For a CODE_LABEL, 1 means always consider this label to be needed. */
514 #define LABEL_PRESERVE_P(RTX) ((RTX)->in_struct)
516 /* For a REG, 1 means the register is used only in an exit test of a loop. */
517 #define REG_LOOP_TEST_P(RTX) ((RTX)->in_struct)
519 /* During sched, for an insn, 1 means that the insn must be scheduled together
520 with the preceding insn. */
521 #define SCHED_GROUP_P(INSN) ((INSN)->in_struct)
523 /* During sched, for the LOG_LINKS of an insn, these cache the adjusted
524 cost of the dependence link. The cost of executing an instruction
525 may vary based on how the results are used. LINK_COST_ZERO is 1 when
526 the cost through the link varies and is unchanged (i.e., the link has
527 zero additional cost). LINK_COST_FREE is 1 when the cost through the
528 link is zero (i.e., the link makes the cost free). In other cases,
529 the adjustment to the cost is recomputed each time it is needed. */
530 #define LINK_COST_ZERO(X) ((X)->jump)
531 #define LINK_COST_FREE(X) ((X)->call)
533 /* For a SET rtx, SET_DEST is the place that is set
534 and SET_SRC is the value it is set to. */
535 #define SET_DEST(RTX) ((RTX)->fld[0].rtx)
536 #define SET_SRC(RTX) ((RTX)->fld[1].rtx)
538 /* For a TRAP_IF rtx, TRAP_CONDITION is an expression. */
539 #define TRAP_CONDITION(RTX) ((RTX)->fld[0].rtx)
541 /* 1 in a SYMBOL_REF if it addresses this function's constants pool. */
542 #define CONSTANT_POOL_ADDRESS_P(RTX) ((RTX)->unchanging)
544 /* Flag in a SYMBOL_REF for machine-specific purposes. */
545 #define SYMBOL_REF_FLAG(RTX) ((RTX)->volatil)
547 /* 1 means a SYMBOL_REF has been the library function in emit_library_call. */
548 #define SYMBOL_REF_USED(RTX) ((RTX)->used)
550 /* For an INLINE_HEADER rtx, FIRST_FUNCTION_INSN is the first insn
551 of the function that is not involved in copying parameters to
552 pseudo-registers. FIRST_PARM_INSN is the very first insn of
553 the function, including the parameter copying.
554 We keep this around in case we must splice
555 this function into the assembly code at the end of the file.
556 FIRST_LABELNO is the first label number used by the function (inclusive).
557 LAST_LABELNO is the last label used by the function (exclusive).
558 MAX_REGNUM is the largest pseudo-register used by that function.
559 FUNCTION_ARGS_SIZE is the size of the argument block in the stack.
560 POPS_ARGS is the number of bytes of input arguments popped by the function
561 STACK_SLOT_LIST is the list of stack slots.
562 FORCED_LABELS is the list of labels whose address was taken.
563 FUNCTION_FLAGS are where single-bit flags are saved.
564 OUTGOING_ARGS_SIZE is the size of the largest outgoing stack parameter list.
565 ORIGINAL_ARG_VECTOR is a vector of the original DECL_RTX values
566 for the function arguments.
567 ORIGINAL_DECL_INITIAL is a pointer to the original DECL_INITIAL for the
569 INLINE_REGNO_REG_RTX, INLINE_REGNO_POINTER_FLAG, and
570 INLINE_REGNO_POINTER_ALIGN are pointers to the corresponding arrays.
572 We want this to lay down like an INSN. The PREV_INSN field
573 is always NULL. The NEXT_INSN field always points to the
574 first function insn of the function being squirreled away. */
576 #define FIRST_FUNCTION_INSN(RTX) ((RTX)->fld[2].rtx)
577 #define FIRST_PARM_INSN(RTX) ((RTX)->fld[3].rtx)
578 #define FIRST_LABELNO(RTX) ((RTX)->fld[4].rtint)
579 #define LAST_LABELNO(RTX) ((RTX)->fld[5].rtint)
580 #define MAX_PARMREG(RTX) ((RTX)->fld[6].rtint)
581 #define MAX_REGNUM(RTX) ((RTX)->fld[7].rtint)
582 #define FUNCTION_ARGS_SIZE(RTX) ((RTX)->fld[8].rtint)
583 #define POPS_ARGS(RTX) ((RTX)->fld[9].rtint)
584 #define STACK_SLOT_LIST(RTX) ((RTX)->fld[10].rtx)
585 #define FORCED_LABELS(RTX) ((RTX)->fld[11].rtx)
586 #define FUNCTION_FLAGS(RTX) ((RTX)->fld[12].rtint)
587 #define OUTGOING_ARGS_SIZE(RTX) ((RTX)->fld[13].rtint)
588 #define ORIGINAL_ARG_VECTOR(RTX) ((RTX)->fld[14].rtvec)
589 #define ORIGINAL_DECL_INITIAL(RTX) ((RTX)->fld[15].rtx)
590 #define INLINE_REGNO_REG_RTX(RTX) ((RTX)->fld[16].rtvec)
591 #define INLINE_REGNO_POINTER_FLAG(RTX) ((RTX)->fld[17].rtstr)
592 #define INLINE_REGNO_POINTER_ALIGN(RTX) ((RTX)->fld[18].rtstr)
594 /* In FUNCTION_FLAGS we save some variables computed when emitting the code
595 for the function and which must be `or'ed into the current flag values when
596 insns from that function are being inlined. */
598 /* These ought to be an enum, but non-ANSI compilers don't like that. */
599 #define FUNCTION_FLAGS_CALLS_ALLOCA 01
600 #define FUNCTION_FLAGS_CALLS_SETJMP 02
601 #define FUNCTION_FLAGS_RETURNS_STRUCT 04
602 #define FUNCTION_FLAGS_RETURNS_PCC_STRUCT 010
603 #define FUNCTION_FLAGS_NEEDS_CONTEXT 020
604 #define FUNCTION_FLAGS_HAS_NONLOCAL_LABEL 040
605 #define FUNCTION_FLAGS_RETURNS_POINTER 0100
606 #define FUNCTION_FLAGS_USES_CONST_POOL 0200
607 #define FUNCTION_FLAGS_CALLS_LONGJMP 0400
608 #define FUNCTION_FLAGS_USES_PIC_OFFSET_TABLE 01000
610 /* Define a macro to look for REG_INC notes,
611 but save time on machines where they never exist. */
613 /* Don't continue this line--convex cc version 4.1 would lose. */
614 #if (defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT) || defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT))
615 #define FIND_REG_INC_NOTE(insn, reg) (find_reg_note ((insn), REG_INC, (reg)))
617 #define FIND_REG_INC_NOTE(insn, reg) 0
620 /* Indicate whether the machine has any sort of auto increment addressing.
621 If not, we can avoid checking for REG_INC notes. */
623 /* Don't continue this line--convex cc version 4.1 would lose. */
624 #if (defined (HAVE_PRE_INCREMENT) || defined (HAVE_PRE_DECREMENT) || defined (HAVE_POST_INCREMENT) || defined (HAVE_POST_DECREMENT))
628 /* Generally useful functions. */
630 /* The following functions accept a wide integer argument. Rather than
631 having to cast on every function call, we use a macro instead, that is
632 defined here and in tree.h. */
635 #define exact_log2(N) exact_log2_wide ((HOST_WIDE_INT) (N))
636 #define floor_log2(N) floor_log2_wide ((HOST_WIDE_INT) (N))
639 #define plus_constant(X,C) plus_constant_wide (X, (HOST_WIDE_INT) (C))
641 #define plus_constant_for_output(X,C) \
642 plus_constant_for_output_wide (X, (HOST_WIDE_INT) (C))
644 extern rtx plus_constant_wide PROTO((rtx, HOST_WIDE_INT));
645 extern rtx plus_constant_for_output_wide PROTO((rtx, HOST_WIDE_INT));
647 #define GEN_INT(N) gen_rtx (CONST_INT, VOIDmode, (HOST_WIDE_INT) (N))
649 extern rtx bc_gen_rtx ();
651 extern rtx gen_rtx PVPROTO((enum rtx_code,
652 enum machine_mode, ...));
653 extern rtvec gen_rtvec PVPROTO((int, ...));
655 extern rtx read_rtx STDIO_PROTO((FILE *));
658 /* At present, don't prototype xrealloc, since all of the callers don't
659 cast their pointers to char *, and all of the xrealloc's don't use
661 extern char *xmalloc PROTO((size_t));
662 extern char *xrealloc PROTO((void *, size_t));
664 extern char *xmalloc ();
665 extern char *xrealloc ();
668 extern char *oballoc PROTO((int));
669 extern char *permalloc PROTO((int));
670 extern void free PROTO((void *));
671 extern rtx rtx_alloc PROTO((RTX_CODE));
672 extern rtvec rtvec_alloc PROTO((int));
673 extern rtx find_reg_note PROTO((rtx, enum reg_note, rtx));
674 extern rtx find_regno_note PROTO((rtx, enum reg_note, int));
675 extern int find_reg_fusage PROTO((rtx, enum rtx_code, rtx));
676 extern int find_regno_fusage PROTO((rtx, enum rtx_code, int));
677 extern HOST_WIDE_INT get_integer_term PROTO((rtx));
678 extern rtx get_related_value PROTO((rtx));
679 extern rtx single_set PROTO((rtx));
680 extern rtx find_last_value PROTO((rtx, rtx *, rtx));
681 extern rtx copy_rtx PROTO((rtx));
682 extern rtx copy_rtx_if_shared PROTO((rtx));
683 extern rtx copy_most_rtx PROTO((rtx, rtx));
684 extern rtx replace_rtx PROTO((rtx, rtx, rtx));
685 extern rtvec gen_rtvec_v PROTO((int, rtx *));
686 extern rtvec gen_rtvec_vv PROTO((int, rtunion *));
687 extern rtx gen_reg_rtx PROTO((enum machine_mode));
688 extern rtx gen_label_rtx PROTO((void));
689 extern rtx gen_inline_header_rtx PROTO((rtx, rtx, int, int, int, int,
690 int, int, rtx, rtx, int, int,
692 rtvec, char *, char *));
693 extern rtx gen_lowpart_common PROTO((enum machine_mode, rtx));
694 extern rtx gen_lowpart PROTO((enum machine_mode, rtx));
695 extern rtx gen_lowpart_if_possible PROTO((enum machine_mode, rtx));
696 extern rtx gen_highpart PROTO((enum machine_mode, rtx));
697 extern rtx gen_realpart PROTO((enum machine_mode, rtx));
698 extern rtx gen_imagpart PROTO((enum machine_mode, rtx));
699 extern rtx operand_subword PROTO((rtx, int, int, enum machine_mode));
700 extern rtx operand_subword_force PROTO((rtx, int, enum machine_mode));
701 extern int subreg_lowpart_p PROTO((rtx));
702 extern rtx make_safe_from PROTO((rtx, rtx));
703 extern rtx convert_memory_address PROTO((enum machine_mode, rtx));
704 extern rtx memory_address PROTO((enum machine_mode, rtx));
705 extern rtx get_insns PROTO((void));
706 extern rtx get_last_insn PROTO((void));
707 extern rtx get_last_insn_anywhere PROTO((void));
708 extern void start_sequence PROTO((void));
709 extern void push_to_sequence PROTO((rtx));
710 extern void end_sequence PROTO((void));
711 extern rtx gen_sequence PROTO((void));
712 extern rtx immed_double_const PROTO((HOST_WIDE_INT, HOST_WIDE_INT, enum machine_mode));
713 extern rtx force_const_mem PROTO((enum machine_mode, rtx));
714 extern rtx force_reg PROTO((enum machine_mode, rtx));
715 extern rtx get_pool_constant PROTO((rtx));
716 extern enum machine_mode get_pool_mode PROTO((rtx));
717 extern int get_pool_offset PROTO((rtx));
718 extern rtx simplify_subtraction PROTO((rtx));
719 extern rtx assign_stack_local PROTO((enum machine_mode, int, int));
720 extern rtx assign_stack_temp PROTO((enum machine_mode, int, int));
721 extern rtx assign_temp PROTO((union tree_node *, int,
723 extern rtx protect_from_queue PROTO((rtx, int));
724 extern void emit_queue PROTO((void));
725 extern rtx emit_move_insn PROTO((rtx, rtx));
726 extern rtx emit_insn_before PROTO((rtx, rtx));
727 extern rtx emit_jump_insn_before PROTO((rtx, rtx));
728 extern rtx emit_call_insn_before PROTO((rtx, rtx));
729 extern rtx emit_barrier_before PROTO((rtx));
730 extern rtx emit_note_before PROTO((int, rtx));
731 extern rtx emit_insn_after PROTO((rtx, rtx));
732 extern rtx emit_jump_insn_after PROTO((rtx, rtx));
733 extern rtx emit_barrier_after PROTO((rtx));
734 extern rtx emit_label_after PROTO((rtx, rtx));
735 extern rtx emit_note_after PROTO((int, rtx));
736 extern rtx emit_line_note_after PROTO((char *, int, rtx));
737 extern rtx emit_insn PROTO((rtx));
738 extern rtx emit_insns PROTO((rtx));
739 extern rtx emit_insns_before PROTO((rtx, rtx));
740 extern rtx emit_insns_after PROTO((rtx, rtx));
741 extern rtx emit_jump_insn PROTO((rtx));
742 extern rtx emit_call_insn PROTO((rtx));
743 extern rtx emit_label PROTO((rtx));
744 extern rtx emit_barrier PROTO((void));
745 extern rtx emit_line_note PROTO((char *, int));
746 extern rtx emit_note PROTO((char *, int));
747 extern rtx emit_line_note_force PROTO((char *, int));
748 extern rtx make_insn_raw PROTO((rtx));
749 extern rtx previous_insn PROTO((rtx));
750 extern rtx next_insn PROTO((rtx));
751 extern rtx prev_nonnote_insn PROTO((rtx));
752 extern rtx next_nonnote_insn PROTO((rtx));
753 extern rtx prev_real_insn PROTO((rtx));
754 extern rtx next_real_insn PROTO((rtx));
755 extern rtx prev_active_insn PROTO((rtx));
756 extern rtx next_active_insn PROTO((rtx));
757 extern rtx prev_label PROTO((rtx));
758 extern rtx next_label PROTO((rtx));
759 extern rtx next_cc0_user PROTO((rtx));
760 extern rtx prev_cc0_setter PROTO((rtx));
761 extern rtx reg_set_last PROTO((rtx, rtx));
762 extern rtx next_nondeleted_insn PROTO((rtx));
763 extern enum rtx_code reverse_condition PROTO((enum rtx_code));
764 extern enum rtx_code swap_condition PROTO((enum rtx_code));
765 extern enum rtx_code unsigned_condition PROTO((enum rtx_code));
766 extern enum rtx_code signed_condition PROTO((enum rtx_code));
767 extern rtx find_equiv_reg PROTO((rtx, rtx, enum reg_class, int, short *, int, enum machine_mode));
768 extern rtx squeeze_notes PROTO((rtx, rtx));
769 extern rtx delete_insn PROTO((rtx));
770 extern void delete_jump PROTO((rtx));
771 extern rtx get_label_before PROTO((rtx));
772 extern rtx get_label_after PROTO((rtx));
773 extern rtx follow_jumps PROTO((rtx));
774 extern rtx adj_offsettable_operand PROTO((rtx, int));
775 extern rtx try_split PROTO((rtx, rtx, int));
776 extern rtx split_insns PROTO((rtx, rtx));
777 extern rtx simplify_unary_operation PROTO((enum rtx_code, enum machine_mode, rtx, enum machine_mode));
778 extern rtx simplify_binary_operation PROTO((enum rtx_code, enum machine_mode, rtx, rtx));
779 extern rtx simplify_ternary_operation PROTO((enum rtx_code, enum machine_mode, enum machine_mode, rtx, rtx, rtx));
780 extern rtx simplify_relational_operation PROTO((enum rtx_code, enum machine_mode, rtx, rtx));
781 extern rtx nonlocal_label_rtx_list PROTO((void));
782 extern rtx gen_move_insn PROTO((rtx, rtx));
783 extern rtx gen_jump PROTO((rtx));
784 extern rtx gen_beq PROTO((rtx));
785 extern rtx gen_bge PROTO((rtx));
786 extern rtx gen_ble PROTO((rtx));
787 extern rtx eliminate_constant_term PROTO((rtx, rtx *));
788 extern rtx expand_complex_abs PROTO((enum machine_mode, rtx, rtx, int));
789 extern enum machine_mode choose_hard_reg_mode PROTO((int, int));
791 /* Maximum number of parallel sets and clobbers in any insn in this fn.
792 Always at least 3, since the combiner could put that many togetherm
793 and we want this to remain correct for all the remaining passes. */
795 extern int max_parallel;
797 extern int asm_noperands PROTO((rtx));
798 extern char *decode_asm_operands PROTO((rtx, rtx *, rtx **, char **, enum machine_mode *));
800 extern enum reg_class reg_preferred_class PROTO((int));
801 extern enum reg_class reg_alternate_class PROTO((int));
803 extern rtx get_first_nonparm_insn PROTO((void));
805 /* Standard pieces of rtx, to be substituted directly into things. */
808 extern rtx const0_rtx;
809 extern rtx const1_rtx;
810 extern rtx const2_rtx;
811 extern rtx constm1_rtx;
812 extern rtx const_true_rtx;
814 extern rtx const_tiny_rtx[3][(int) MAX_MACHINE_MODE];
816 /* Returns a constant 0 rtx in mode MODE. Integer modes are treated the
819 #define CONST0_RTX(MODE) (const_tiny_rtx[0][(int) (MODE)])
821 /* Likewise, for the constants 1 and 2. */
823 #define CONST1_RTX(MODE) (const_tiny_rtx[1][(int) (MODE)])
824 #define CONST2_RTX(MODE) (const_tiny_rtx[2][(int) (MODE)])
826 /* All references to certain hard regs, except those created
827 by allocating pseudo regs into them (when that's possible),
828 go through these unique rtx objects. */
829 extern rtx stack_pointer_rtx;
830 extern rtx frame_pointer_rtx;
831 extern rtx hard_frame_pointer_rtx;
832 extern rtx arg_pointer_rtx;
833 extern rtx pic_offset_table_rtx;
834 extern rtx struct_value_rtx;
835 extern rtx struct_value_incoming_rtx;
836 extern rtx static_chain_rtx;
837 extern rtx static_chain_incoming_rtx;
839 /* If HARD_FRAME_POINTER_REGNUM is defined, then a special dummy reg
840 is used to represent the frame pointer. This is because the
841 hard frame pointer and the automatic variables are separated by an amount
842 that cannot be determined until after register allocation. We can assume
843 that in this case ELIMINABLE_REGS will be defined, one action of which
844 will be to eliminate FRAME_POINTER_REGNUM into HARD_FRAME_POINTER_REGNUM. */
845 #ifndef HARD_FRAME_POINTER_REGNUM
846 #define HARD_FRAME_POINTER_REGNUM FRAME_POINTER_REGNUM
849 /* Virtual registers are used during RTL generation to refer to locations into
850 the stack frame when the actual location isn't known until RTL generation
851 is complete. The routine instantiate_virtual_regs replaces these with
852 the proper value, which is normally {frame,arg,stack}_pointer_rtx plus
855 #define FIRST_VIRTUAL_REGISTER (FIRST_PSEUDO_REGISTER)
857 /* This points to the first word of the incoming arguments passed on the stack,
858 either by the caller or by the callee when pretending it was passed by the
861 extern rtx virtual_incoming_args_rtx;
863 #define VIRTUAL_INCOMING_ARGS_REGNUM (FIRST_VIRTUAL_REGISTER)
865 /* If FRAME_GROWS_DOWNWARD, this points to immediately above the first
866 variable on the stack. Otherwise, it points to the first variable on
869 extern rtx virtual_stack_vars_rtx;
871 #define VIRTUAL_STACK_VARS_REGNUM ((FIRST_VIRTUAL_REGISTER) + 1)
873 /* This points to the location of dynamically-allocated memory on the stack
874 immediately after the stack pointer has been adjusted by the amount
877 extern rtx virtual_stack_dynamic_rtx;
879 #define VIRTUAL_STACK_DYNAMIC_REGNUM ((FIRST_VIRTUAL_REGISTER) + 2)
881 /* This points to the location in the stack at which outgoing arguments should
882 be written when the stack is pre-pushed (arguments pushed using push
883 insns always use sp). */
885 extern rtx virtual_outgoing_args_rtx;
887 #define VIRTUAL_OUTGOING_ARGS_REGNUM ((FIRST_VIRTUAL_REGISTER) + 3)
889 #define LAST_VIRTUAL_REGISTER ((FIRST_VIRTUAL_REGISTER) + 3)
891 extern rtx find_next_ref PROTO((rtx, rtx));
892 extern rtx *find_single_use PROTO((rtx, rtx, rtx *));
894 /* It is hard to write the prototype for expand_expr, since it needs
895 expr.h to be included for the enumeration. */
897 extern rtx expand_expr ();
899 extern rtx output_constant_def PROTO((union tree_node *));
900 extern rtx immed_real_const PROTO((union tree_node *));
901 extern union tree_node *make_tree PROTO((union tree_node *, rtx));
904 extern void fatal_insn_not_found PROTO((rtx));
905 extern void fatal_insn PROTO((char *, rtx));
907 /* Define a default value for STORE_FLAG_VALUE. */
909 #ifndef STORE_FLAG_VALUE
910 #define STORE_FLAG_VALUE 1
913 /* Nonzero after end of reload pass.
914 Set to 1 or 0 by toplev.c. */
916 extern int reload_completed;
918 /* Set to 1 while reload_as_needed is operating.
919 Required by some machines to handle any generated moves differently. */
921 extern int reload_in_progress;
923 /* If this is nonzero, we do not bother generating VOLATILE
924 around volatile memory references, and we are willing to
925 output indirect addresses. If cse is to follow, we reject
926 indirect addresses so a useful potential cse is generated;
927 if it is used only once, instruction combination will produce
928 the same indirect address eventually. */
929 extern int cse_not_expected;
931 /* Indexed by pseudo register number, gives the rtx for that pseudo.
932 Allocated in parallel with regno_pointer_flag. */
933 extern rtx *regno_reg_rtx;
935 /* Vector indexed by regno; contains the alignment in bytes for a
936 register that contains a pointer, if known. */
937 extern char *regno_pointer_align;
938 #define REGNO_POINTER_ALIGN(REGNO) regno_pointer_align[REGNO]
940 /* Translates rtx code to tree code, for those codes needed by
941 REAL_ARITHMETIC. The function returns an int because the caller may not
942 know what `enum tree_code' means. */
944 extern int rtx_to_tree_code PROTO((enum rtx_code));