Annotation of gcc/final.c, revision 1.1

1.1     ! root        1: /* Convert RTL to assembler code and output it, for GNU compiler.
        !             2:    Copyright (C) 1987, 1988, 1989, 1992 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: 
        !            21: /* This is the final pass of the compiler.
        !            22:    It looks at the rtl code for a function and outputs assembler code.
        !            23: 
        !            24:    Call `final_start_function' to output the assembler code for function entry,
        !            25:    `final' to output assembler code for some RTL code,
        !            26:    `final_end_function' to output assembler code for function exit.
        !            27:    If a function is compiled in several pieces, each piece is
        !            28:    output separately with `final'.
        !            29: 
        !            30:    Some optimizations are also done at this level.
        !            31:    Move instructions that were made unnecessary by good register allocation
        !            32:    are detected and omitted from the output.  (Though most of these
        !            33:    are removed by the last jump pass.)
        !            34: 
        !            35:    Instructions to set the condition codes are omitted when it can be
        !            36:    seen that the condition codes already had the desired values.
        !            37: 
        !            38:    In some cases it is sufficient if the inherited condition codes
        !            39:    have related values, but this may require the following insn
        !            40:    (the one that tests the condition codes) to be modified.
        !            41: 
        !            42:    The code for the function prologue and epilogue are generated
        !            43:    directly as assembler code by the macros FUNCTION_PROLOGUE and
        !            44:    FUNCTION_EPILOGUE.  Those instructions never exist as rtl.  */
        !            45: 
        !            46: #include <stdio.h>
        !            47: #include "config.h"
        !            48: #include "gvarargs.h"
        !            49: #include "rtl.h"
        !            50: #include "regs.h"
        !            51: #include "insn-config.h"
        !            52: #include "insn-attr.h"
        !            53: #include "insn-codes.h"
        !            54: #include "recog.h"
        !            55: #include "conditions.h"
        !            56: #include "flags.h"
        !            57: #include "real.h"
        !            58: #include "output.h"
        !            59: #include "hard-reg-set.h"
        !            60: 
        !            61: #ifndef ASM_STABD_OP
        !            62: #define ASM_STABD_OP ".stabd"
        !            63: #endif
        !            64: 
        !            65: /* Get N_SLINE and N_SOL from stab.h if we can expect the file to exist.  */
        !            66: #ifdef DBX_DEBUGGING_INFO
        !            67: #ifdef USG
        !            68: #include "gstab.h"  /* If doing DBX on sysV, use our own stab.h.  */
        !            69: #else
        !            70: #include <stab.h>  /* On BSD, use the system's stab.h.  */
        !            71: #endif /* not USG */
        !            72: #endif /* DBX_DEBUGGING_INFO */
        !            73: 
        !            74: /* .stabd code for line number.  */
        !            75: #ifndef N_SLINE
        !            76: #define        N_SLINE 0x44
        !            77: #endif
        !            78: 
        !            79: /* .stabs code for included file name.  */
        !            80: #ifndef N_SOL
        !            81: #define        N_SOL 0x84
        !            82: #endif
        !            83: 
        !            84: #ifndef INT_TYPE_SIZE
        !            85: #define INT_TYPE_SIZE BITS_PER_WORD
        !            86: #endif
        !            87: 
        !            88: /* If we aren't using cc0, CC_STATUS_INIT shouldn't exist.  So define a
        !            89:    null default for it to save conditionalization later.  */
        !            90: #ifndef CC_STATUS_INIT
        !            91: #define CC_STATUS_INIT
        !            92: #endif
        !            93: 
        !            94: /* How to start an assembler comment.  */
        !            95: #ifndef ASM_COMMENT_START
        !            96: #define ASM_COMMENT_START ";#"
        !            97: #endif
        !            98: 
        !            99: rtx peephole ();
        !           100: void output_asm_insn ();
        !           101: rtx alter_subreg ();
        !           102: static int alter_cond ();
        !           103: void output_asm_label ();
        !           104: static void output_operand ();
        !           105: void output_address ();
        !           106: void output_addr_const ();
        !           107: static void output_source_line ();
        !           108: rtx final_scan_insn ();
        !           109: void profile_function ();
        !           110: 
        !           111: #ifdef HAVE_ATTR_length
        !           112: static int asm_insn_count ();
        !           113: #endif
        !           114: 
        !           115: /* Nonzero means this function is a leaf function, with no function calls. 
        !           116:    This variable exists to be examined in FUNCTION_PROLOGUE
        !           117:    and FUNCTION_EPILOGUE.  Always zero, unless set by some action.  */
        !           118: int leaf_function;
        !           119: 
        !           120: int leaf_function_p ();
        !           121: 
        !           122: #ifdef LEAF_REGISTERS
        !           123: int only_leaf_regs_used ();
        !           124: static void leaf_renumber_regs ();
        !           125: void leaf_renumber_regs_insn ();
        !           126: #endif
        !           127: 
        !           128: /* Last insn processed by final_scan_insn.  */
        !           129: static rtx debug_insn = 0;
        !           130: 
        !           131: /* Line number of last NOTE.  */
        !           132: static int last_linenum;
        !           133: 
        !           134: /* Number of basic blocks seen so far;
        !           135:    used if profile_block_flag is set.  */
        !           136: static int count_basic_blocks;
        !           137: 
        !           138: /* Nonzero while outputting an `asm' with operands.
        !           139:    This means that inconsistencies are the user's fault, so don't abort.
        !           140:    The precise value is the insn being output, to pass to error_for_asm.  */
        !           141: static rtx this_is_asm_operands;
        !           142: 
        !           143: /* Number of operands of this insn, for an `asm' with operands.  */
        !           144: static int insn_noperands;
        !           145: 
        !           146: /* Compare optimization flag.  */
        !           147: 
        !           148: static rtx last_ignored_compare = 0;
        !           149: 
        !           150: /* Flag indicating this insn is the start of a new basic block.  */
        !           151: 
        !           152: static int new_block = 1;
        !           153: 
        !           154: /* All the symbol-blocks (levels of scoping) in the compilation
        !           155:    are assigned sequence numbers in order of appearance of the
        !           156:    beginnings of the symbol-blocks.  Both final and dbxout do this,
        !           157:    and assume that they will both give the same number to each block.
        !           158:    Final uses these sequence numbers to generate assembler label names
        !           159:    LBBnnn and LBEnnn for the beginning and end of the symbol-block.
        !           160:    Dbxout uses the sequence nunbers to generate references to the same labels
        !           161:    from the dbx debugging information.
        !           162: 
        !           163:    Sdb records this level at the beginning of each function,
        !           164:    in order to find the current level when recursing down declarations.
        !           165:    It outputs the block beginning and endings
        !           166:    at the point in the asm file where the blocks would begin and end.  */
        !           167: 
        !           168: int next_block_index;
        !           169: 
        !           170: /* Assign a unique number to each insn that is output.
        !           171:    This can be used to generate unique local labels.  */
        !           172: 
        !           173: static int insn_counter = 0;
        !           174: 
        !           175: #ifdef HAVE_cc0
        !           176: /* This variable contains machine-dependent flags (defined in tm.h)
        !           177:    set and examined by output routines
        !           178:    that describe how to interpret the condition codes properly.  */
        !           179: 
        !           180: CC_STATUS cc_status;
        !           181: 
        !           182: /* During output of an insn, this contains a copy of cc_status
        !           183:    from before the insn.  */
        !           184: 
        !           185: CC_STATUS cc_prev_status;
        !           186: #endif
        !           187: 
        !           188: /* Indexed by hardware reg number, is 1 if that register is ever
        !           189:    used in the current function.
        !           190: 
        !           191:    In life_analysis, or in stupid_life_analysis, this is set
        !           192:    up to record the hard regs used explicitly.  Reload adds
        !           193:    in the hard regs used for holding pseudo regs.  Final uses
        !           194:    it to generate the code in the function prologue and epilogue
        !           195:    to save and restore registers as needed.  */
        !           196: 
        !           197: char regs_ever_live[FIRST_PSEUDO_REGISTER];
        !           198: 
        !           199: /* Nonzero means current function must be given a frame pointer.
        !           200:    Set in stmt.c if anything is allocated on the stack there.
        !           201:    Set in reload1.c if anything is allocated on the stack there.  */
        !           202: 
        !           203: int frame_pointer_needed;
        !           204: 
        !           205: /* Assign unique numbers to labels generated for profiling.  */
        !           206: 
        !           207: int profile_label_no;
        !           208: 
        !           209: /* Length so far allocated in PENDING_BLOCKS.  */
        !           210: 
        !           211: static int max_block_depth;
        !           212: 
        !           213: /* Stack of sequence numbers of symbol-blocks of which we have seen the
        !           214:    beginning but not yet the end.  Sequence numbers are assigned at
        !           215:    the beginning; this stack allows us to find the sequence number
        !           216:    of a block that is ending.  */
        !           217: 
        !           218: static int *pending_blocks;
        !           219: 
        !           220: /* Number of elements currently in use in PENDING_BLOCKS.  */
        !           221: 
        !           222: static int block_depth;
        !           223: 
        !           224: /* Nonzero if have enabled APP processing of our assembler output.  */
        !           225: 
        !           226: static int app_on;
        !           227: 
        !           228: /* If we are outputting an insn sequence, this contains the sequence rtx.
        !           229:    Zero otherwise.  */
        !           230: 
        !           231: rtx final_sequence;
        !           232: 
        !           233: /* Indexed by line number, nonzero if there is a note for that line.  */
        !           234: 
        !           235: static char *line_note_exists;
        !           236: 
        !           237: /* Initialize data in final at the beginning of a compilation.  */
        !           238: 
        !           239: void
        !           240: init_final (filename)
        !           241:      char *filename;
        !           242: {
        !           243:   next_block_index = 2;
        !           244:   app_on = 0;
        !           245:   max_block_depth = 20;
        !           246:   pending_blocks = (int *) xmalloc (20 * sizeof *pending_blocks);
        !           247:   final_sequence = 0;
        !           248: }
        !           249: 
        !           250: /* Called at end of source file,
        !           251:    to output the block-profiling table for this entire compilation.  */
        !           252: 
        !           253: void
        !           254: end_final (filename)
        !           255:      char *filename;
        !           256: {
        !           257:   int i;
        !           258: 
        !           259:   if (profile_block_flag)
        !           260:     {
        !           261:       char name[12];
        !           262: 
        !           263:       data_section ();
        !           264: 
        !           265:       /* Output the main header, of 6 words:
        !           266:         0:  1 if this file's initialized, else 0.
        !           267:         1:  address of file name.
        !           268:         2:  address of table of counts.
        !           269:         4:  number of counts in the table.
        !           270:         5:  always 0, for compatibility with Sun.
        !           271:         6:  extra word added by GNU: address of address table
        !           272:              which contains addresses of basic blocks,
        !           273:              in parallel with the table of counts.  */
        !           274:       ASM_OUTPUT_ALIGN (asm_out_file,
        !           275:                        exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
        !           276: 
        !           277:       ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 0);
        !           278:       assemble_integer (const0_rtx, UNITS_PER_WORD, 1);
        !           279:       ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 1);
        !           280:       assemble_integer (gen_rtx (SYMBOL_REF, Pmode, name), UNITS_PER_WORD, 1);
        !           281:       ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
        !           282:       assemble_integer (gen_rtx (SYMBOL_REF, Pmode, name), UNITS_PER_WORD, 1);
        !           283:       assemble_integer (gen_rtx (CONST_INT, VOIDmode, count_basic_blocks),
        !           284:                        UNITS_PER_WORD, 1);
        !           285:       assemble_integer (const0_rtx, UNITS_PER_WORD, 1);
        !           286:       ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 3);
        !           287:       assemble_integer (gen_rtx (SYMBOL_REF, Pmode, name), UNITS_PER_WORD, 1);
        !           288: 
        !           289:       /* Output the file name.  */
        !           290:       ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 1);
        !           291:       {
        !           292:        int len = strlen (filename);
        !           293:        char *data_file = (char *) alloca (len + 3);
        !           294:        strcpy (data_file, filename);
        !           295:        strip_off_ending (data_file, len);
        !           296:        strcat (data_file, ".d");
        !           297:        assemble_string (data_file, strlen (data_file) + 1);
        !           298:       }
        !           299: 
        !           300:       /* Realign data section.  */
        !           301:       ASM_OUTPUT_ALIGN (asm_out_file,
        !           302:                        exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
        !           303: 
        !           304:       /* Make space for the table of counts.  */
        !           305:       ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 2);
        !           306:       assemble_zeros (INT_TYPE_SIZE / BITS_PER_UNIT * count_basic_blocks);
        !           307: 
        !           308:       /* Output the table of addresses.  */
        !           309:       readonly_data_section ();
        !           310:       ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 3);
        !           311:       for (i = 0; i < count_basic_blocks; i++)
        !           312:        {
        !           313:          char name[12];
        !           314:          ASM_GENERATE_INTERNAL_LABEL (name, "LPB", i);
        !           315:          assemble_integer (gen_rtx (SYMBOL_REF, Pmode, name),
        !           316:                            UNITS_PER_WORD, 1);
        !           317:        }
        !           318: 
        !           319:       /* End with the address of the table of addresses,
        !           320:         so we can find it easily, as the last word in the file's text.  */
        !           321:       ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 3);
        !           322:       assemble_integer (gen_rtx (SYMBOL_REF, Pmode, name), UNITS_PER_WORD, 1);
        !           323:     }
        !           324: }
        !           325: 
        !           326: /* Enable APP processing of subsequent output.
        !           327:    Used before the output from an `asm' statement.  */
        !           328: 
        !           329: void
        !           330: app_enable ()
        !           331: {
        !           332:   if (! app_on)
        !           333:     {
        !           334:       fprintf (asm_out_file, ASM_APP_ON);
        !           335:       app_on = 1;
        !           336:     }
        !           337: }
        !           338: 
        !           339: /* Enable APP processing of subsequent output.
        !           340:    Called from varasm.c before most kinds of output.  */
        !           341: 
        !           342: void
        !           343: app_disable ()
        !           344: {
        !           345:   if (app_on)
        !           346:     {
        !           347:       fprintf (asm_out_file, ASM_APP_OFF);
        !           348:       app_on = 0;
        !           349:     }
        !           350: }
        !           351: 
        !           352: /* Return the number of slots filled in the current 
        !           353:    delayed branch sequence (we don't count the insn needing the
        !           354:    delay slot).   Zero if not in a delayed branch sequence.  */
        !           355: 
        !           356: #ifdef DELAY_SLOTS
        !           357: int
        !           358: dbr_sequence_length ()
        !           359: {
        !           360:   if (final_sequence != 0)
        !           361:     return XVECLEN (final_sequence, 0) - 1;
        !           362:   else
        !           363:     return 0;
        !           364: }
        !           365: #endif
        !           366: 
        !           367: /* The next two pages contain routines used to compute the length of an insn
        !           368:    and to shorten branches.  */
        !           369: 
        !           370: /* Arrays for insn lengths, and addresses.  The latter is referenced by
        !           371:    `insn_current_length'.  */
        !           372: 
        !           373: static short *insn_lengths;
        !           374: int *insn_addresses;
        !           375: 
        !           376: /* Address of insn being processed.  Used by `insn_current_length'.  */
        !           377: int insn_current_address;
        !           378: 
        !           379: /* Indicate the branch shortening hasn't yet been done.  */
        !           380: 
        !           381: void
        !           382: init_insn_lengths ()
        !           383: {
        !           384:   insn_lengths = 0;
        !           385: }
        !           386: 
        !           387: /* Obtain the current length of an insn.  If branch shortening has been done,
        !           388:    get its actual length.  Otherwise, get its maximum length.  */
        !           389: 
        !           390: int
        !           391: get_attr_length (insn)
        !           392:      rtx insn;
        !           393: {
        !           394: #ifdef HAVE_ATTR_length
        !           395:   rtx body;
        !           396:   int i;
        !           397:   int length = 0;
        !           398: 
        !           399:   if (insn_lengths)
        !           400:     return insn_lengths[INSN_UID (insn)];
        !           401:   else
        !           402:     switch (GET_CODE (insn))
        !           403:       {
        !           404:       case NOTE:
        !           405:       case BARRIER:
        !           406:       case CODE_LABEL:
        !           407:        return 0;
        !           408: 
        !           409:       case CALL_INSN:
        !           410:        length = insn_default_length (insn);
        !           411:        break;
        !           412: 
        !           413:       case JUMP_INSN:
        !           414:        body = PATTERN (insn);
        !           415:         if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
        !           416:          {
        !           417:            /* This only takes room if jump tables go into the text section.  */
        !           418: #if !defined(READONLY_DATA_SECTION) || defined(JUMP_TABLES_IN_TEXT_SECTION)
        !           419:            length = (XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC)
        !           420:                      * GET_MODE_SIZE (GET_MODE (body)));
        !           421: 
        !           422:            /* Be pessimistic and assume worst-case alignment.  */
        !           423:            length += (GET_MODE_SIZE (GET_MODE (body)) - 1);
        !           424: #else
        !           425:            return 0;
        !           426: #endif
        !           427:          }
        !           428:        else
        !           429:          length = insn_default_length (insn);
        !           430:        break;
        !           431: 
        !           432:       case INSN:
        !           433:        body = PATTERN (insn);
        !           434:        if (GET_CODE (body) == USE || GET_CODE (body) == CLOBBER)
        !           435:          return 0;
        !           436: 
        !           437:        else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
        !           438:          length = asm_insn_count (insn) * insn_default_length (insn);
        !           439:        else if (GET_CODE (body) == SEQUENCE)
        !           440:          for (i = 0; i < XVECLEN (body, 0); i++)
        !           441:            length += get_attr_length (XVECEXP (body, 0, i));
        !           442:        else
        !           443:          length = insn_default_length (insn);
        !           444:       }
        !           445: 
        !           446: #ifdef ADJUST_INSN_LENGTH
        !           447:   ADJUST_INSN_LENGTH (insn, length);
        !           448: #endif
        !           449:   return length;
        !           450: #else /* not HAVE_ATTR_length */
        !           451:   return 0;
        !           452: #endif /* not HAVE_ATTR_length */
        !           453: }
        !           454: 
        !           455: /* Make a pass over all insns and compute their actual lengths by shortening
        !           456:    any branches of variable length if possible.  */
        !           457: 
        !           458: /* Give a default value for the lowest address in a function.  */
        !           459: 
        !           460: #ifndef FIRST_INSN_ADDRESS
        !           461: #define FIRST_INSN_ADDRESS 0
        !           462: #endif
        !           463: 
        !           464: void
        !           465: shorten_branches (first)
        !           466:      rtx first;
        !           467: {
        !           468: #ifdef HAVE_ATTR_length
        !           469:   rtx insn;
        !           470:   int something_changed = 1;
        !           471:   int max_uid = 0;
        !           472:   char *varying_length;
        !           473:   rtx body;
        !           474:   int uid;
        !           475: 
        !           476:   /* Compute maximum UID and allocate arrays.  */
        !           477:   for (insn = first; insn; insn = NEXT_INSN (insn))
        !           478:     if (INSN_UID (insn) > max_uid)
        !           479:       max_uid = INSN_UID (insn);
        !           480: 
        !           481:   max_uid++;
        !           482:   insn_lengths = (short *) oballoc (max_uid * sizeof (short));
        !           483:   insn_addresses = (int *) oballoc (max_uid * sizeof (int));
        !           484:   varying_length = (char *) oballoc (max_uid * sizeof (char));
        !           485: 
        !           486:   /* Compute initial lengths, addresses, and varying flags for each insn.  */
        !           487:   for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
        !           488:        insn != 0;
        !           489:        insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
        !           490:     {
        !           491:       uid = INSN_UID (insn);
        !           492:       insn_addresses[uid] = insn_current_address;
        !           493:       insn_lengths[uid] = 0;
        !           494:       varying_length[uid] = 0;
        !           495:       
        !           496:       if (GET_CODE (insn) == NOTE || GET_CODE (insn) == BARRIER
        !           497:          || GET_CODE (insn) == CODE_LABEL)
        !           498:        continue;
        !           499: 
        !           500:       body = PATTERN (insn);
        !           501:       if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
        !           502:        {
        !           503:          /* This only takes room if read-only data goes into the text
        !           504:             section.  */
        !           505: #if !defined(READONLY_DATA_SECTION) || defined(JUMP_TABLES_IN_TEXT_SECTION)
        !           506:          int unitsize = GET_MODE_SIZE (GET_MODE (body));
        !           507: 
        !           508:          insn_lengths[uid] = (XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC)
        !           509:                               * GET_MODE_SIZE (GET_MODE (body)));
        !           510: 
        !           511:          /* Account for possible alignment.  */
        !           512:          insn_lengths[uid]
        !           513:            += unitsize - (insn_current_address & (unitsize - 1));
        !           514: #else
        !           515:          ;
        !           516: #endif
        !           517:        }
        !           518:       else if (asm_noperands (body) >= 0)
        !           519:        insn_lengths[uid] = asm_insn_count (body) * insn_default_length (insn);
        !           520:       else if (GET_CODE (body) == SEQUENCE)
        !           521:        {
        !           522:          int i;
        !           523: 
        !           524:          /* Inside a delay slot sequence, we do not do any branch shortening
        !           525:             (on the only machine known to have both variable-length branches
        !           526:             and delay slots, the ROMP, branch-with-execute is the same size
        !           527:             as the maximum branch anyway).  So we only have to handle normal
        !           528:             insns (actually, reorg never puts ASM insns in a delay slot, but
        !           529:             we don't take advantage of that knowlege here).  */
        !           530:          for (i = 0; i < XVECLEN (body, 0); i++)
        !           531:            {
        !           532:              rtx inner_insn = XVECEXP (body, 0, i);
        !           533:              int inner_uid = INSN_UID (inner_insn);
        !           534:              int inner_length;
        !           535: 
        !           536:              if (asm_noperands (PATTERN (XVECEXP (body, 0, i))) >= 0)
        !           537:                inner_length = (asm_insn_count (PATTERN (inner_insn))
        !           538:                                * insn_default_length (inner_insn));
        !           539:              else
        !           540:                inner_length = insn_default_length (inner_insn);
        !           541:              
        !           542:              insn_lengths[inner_uid] = inner_length;
        !           543:              varying_length[inner_uid] = 0;
        !           544:              insn_lengths[uid] += inner_length;
        !           545:            }
        !           546:        }
        !           547:       else if (GET_CODE (body) != USE && GET_CODE (body) != CLOBBER)
        !           548:        {
        !           549:          insn_lengths[uid] = insn_default_length (insn);
        !           550:          varying_length[uid] = insn_variable_length_p (insn);
        !           551:        }
        !           552: 
        !           553:       /* If needed, do any adjustment.  */
        !           554: #ifdef ADJUST_INSN_LENGTH
        !           555:       ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
        !           556: #endif
        !           557:     }
        !           558: 
        !           559:   /* Now loop over all the insns finding varying length insns.  For each,
        !           560:      get the current insn length.  If it has changed, reflect the change.
        !           561:      When nothing changes for a full pass, we are done.  */
        !           562: 
        !           563:   while (something_changed)
        !           564:     {
        !           565:       something_changed = 0;
        !           566:       for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
        !           567:           insn != 0;
        !           568:           insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
        !           569:        {
        !           570:          int new_length;
        !           571: 
        !           572:          uid = INSN_UID (insn);
        !           573:          insn_addresses[uid] = insn_current_address;
        !           574:          if (! varying_length[uid])
        !           575:            continue;
        !           576: 
        !           577:          new_length = insn_current_length (insn);
        !           578:          if (new_length != insn_lengths[uid])
        !           579:            {
        !           580:              insn_lengths[uid] = new_length;
        !           581:              something_changed = 1;
        !           582:            }
        !           583:        }
        !           584:     }
        !           585: #endif /* HAVE_ATTR_length */
        !           586: }
        !           587: 
        !           588: #ifdef HAVE_ATTR_length
        !           589: /* Given the body of an INSN known to be generated by an ASM statement, return
        !           590:    the number of machine instructions likely to be generated for this insn.
        !           591:    This is used to compute its length.  */
        !           592: 
        !           593: static int
        !           594: asm_insn_count (body)
        !           595:      rtx body;
        !           596: {
        !           597:   char *template;
        !           598:   int count = 1;
        !           599: 
        !           600:   for (template = decode_asm_operands (body, 0, 0, 0, 0);
        !           601:        *template; template++)
        !           602:     if (*template == ';' || *template == '\n')
        !           603:       count++;
        !           604: 
        !           605:   return count;
        !           606: }
        !           607: #endif
        !           608: 
        !           609: /* Output assembler code for the start of a function,
        !           610:    and initialize some of the variables in this file
        !           611:    for the new function.  The label for the function and associated
        !           612:    assembler pseudo-ops have already been output in `assemble_start_function'.
        !           613: 
        !           614:    FIRST is the first insn of the rtl for the function being compiled.
        !           615:    FILE is the file to write assembler code to.
        !           616:    OPTIMIZE is nonzero if we should eliminate redundant
        !           617:      test and compare insns.  */
        !           618: 
        !           619: void
        !           620: final_start_function (first, file, optimize)
        !           621:      rtx first;
        !           622:      FILE *file;
        !           623:      int optimize;
        !           624: {
        !           625:   block_depth = 0;
        !           626: 
        !           627:   this_is_asm_operands = 0;
        !           628: 
        !           629: #ifdef NON_SAVING_SETJMP
        !           630:   /* A function that calls setjmp should save and restore all the
        !           631:      call-saved registers on a system where longjmp clobbers them.  */
        !           632:   if (NON_SAVING_SETJMP && current_function_calls_setjmp)
        !           633:     {
        !           634:       int i;
        !           635: 
        !           636:       for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
        !           637:        if (!call_used_regs[i] && !call_fixed_regs[i])
        !           638:          regs_ever_live[i] = 1;
        !           639:     }
        !           640: #endif
        !           641:   
        !           642:   /* Initial line number is supposed to be output
        !           643:      before the function's prologue and label
        !           644:      so that the function's address will not appear to be
        !           645:      in the last statement of the preceding function.  */
        !           646:   if (NOTE_LINE_NUMBER (first) != NOTE_INSN_DELETED)
        !           647:     {
        !           648:       if (write_symbols == SDB_DEBUG)
        !           649:        /* For sdb, let's not, but say we did.
        !           650:           We need to set last_linenum for sdbout_function_begin,
        !           651:           but we can't have an actual line number before the .bf symbol.
        !           652:           (sdb_begin_function_line is not set,
        !           653:           and other compilers don't do it.)  */
        !           654:        last_linenum = NOTE_LINE_NUMBER (first);
        !           655:       else
        !           656:        output_source_line (file, first);
        !           657:     }
        !           658: 
        !           659: #ifdef LEAF_REG_REMAP
        !           660:   if (leaf_function)
        !           661:     leaf_renumber_regs (first);
        !           662: #endif
        !           663: 
        !           664:   /* The Sun386i and perhaps other machines don't work right
        !           665:      if the profiling code comes after the prologue.  */
        !           666: #ifdef PROFILE_BEFORE_PROLOGUE
        !           667:   if (profile_flag)
        !           668:     profile_function (file);
        !           669: #endif /* PROFILE_BEFORE_PROLOGUE */
        !           670: 
        !           671: #ifdef FUNCTION_PROLOGUE
        !           672:   /* First output the function prologue: code to set up the stack frame.  */
        !           673:   FUNCTION_PROLOGUE (file, get_frame_size ());
        !           674: #endif
        !           675: 
        !           676: #ifdef SDB_DEBUGGING_INFO
        !           677:   if (write_symbols == SDB_DEBUG)
        !           678:     next_block_index = 1;
        !           679: #endif
        !           680: 
        !           681: #ifdef FUNCTION_BLOCK_PROFILER
        !           682:   if (profile_block_flag)
        !           683:     {
        !           684:       FUNCTION_BLOCK_PROFILER (file, profile_label_no);
        !           685:     }
        !           686: #endif /* FUNCTION_BLOCK_PROFILER */
        !           687: 
        !           688: #ifndef PROFILE_BEFORE_PROLOGUE
        !           689:   if (profile_flag)
        !           690:     profile_function (file);
        !           691: #endif /* not PROFILE_BEFORE_PROLOGUE */
        !           692: 
        !           693:   profile_label_no++;
        !           694: }
        !           695: 
        !           696: void
        !           697: profile_function (file)
        !           698:      FILE *file;
        !           699: {
        !           700:   int align = MIN (BIGGEST_ALIGNMENT, INT_TYPE_SIZE);
        !           701:   int sval = current_function_returns_struct;
        !           702:   int cxt = current_function_needs_context;
        !           703: 
        !           704:   data_section ();
        !           705:   ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
        !           706:   ASM_OUTPUT_INTERNAL_LABEL (file, "LP", profile_label_no);
        !           707:   assemble_integer (const0_rtx, UNITS_PER_WORD, 1);
        !           708: 
        !           709:   text_section ();
        !           710: 
        !           711: #ifdef STRUCT_VALUE_INCOMING_REGNUM
        !           712:   if (sval)
        !           713:     ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_INCOMING_REGNUM);
        !           714: #else
        !           715: #ifdef STRUCT_VALUE_REGNUM
        !           716:   if (sval)
        !           717:     ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_REGNUM);
        !           718: #endif
        !           719: #endif
        !           720: 
        !           721: #if 0
        !           722: #ifdef STATIC_CHAIN_INCOMING_REGNUM
        !           723:   if (cxt)
        !           724:     ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_INCOMING_REGNUM);
        !           725: #else
        !           726: #ifdef STATIC_CHAIN_REGNUM
        !           727:   if (cxt)
        !           728:     ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_REGNUM);
        !           729: #endif
        !           730: #endif
        !           731: #endif                         /* 0 */
        !           732: 
        !           733:   FUNCTION_PROFILER (file, profile_label_no);
        !           734: 
        !           735: #if 0
        !           736: #ifdef STATIC_CHAIN_INCOMING_REGNUM
        !           737:   if (cxt)
        !           738:     ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_INCOMING_REGNUM);
        !           739: #else
        !           740: #ifdef STATIC_CHAIN_REGNUM
        !           741:   if (cxt)
        !           742:     ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_REGNUM);
        !           743: #endif
        !           744: #endif
        !           745: #endif                         /* 0 */
        !           746: 
        !           747: #ifdef STRUCT_VALUE_INCOMING_REGNUM
        !           748:   if (sval)
        !           749:     ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_INCOMING_REGNUM);
        !           750: #else
        !           751: #ifdef STRUCT_VALUE_REGNUM
        !           752:   if (sval)
        !           753:     ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_REGNUM);
        !           754: #endif
        !           755: #endif
        !           756: }
        !           757: 
        !           758: /* Output assembler code for the end of a function.
        !           759:    For clarity, args are same as those of `final_start_function'
        !           760:    even though not all of them are needed.  */
        !           761: 
        !           762: void
        !           763: final_end_function (first, file, optimize)
        !           764:      rtx first;
        !           765:      FILE *file;
        !           766:      int optimize;
        !           767: {
        !           768:   if (app_on)
        !           769:     {
        !           770:       fprintf (file, ASM_APP_OFF);
        !           771:       app_on = 0;
        !           772:     }
        !           773: 
        !           774: #ifdef SDB_DEBUGGING_INFO
        !           775:   if (write_symbols == SDB_DEBUG)
        !           776:     sdbout_end_function (last_linenum);
        !           777: #endif
        !           778: 
        !           779: #ifdef FUNCTION_EPILOGUE
        !           780:   /* Finally, output the function epilogue:
        !           781:      code to restore the stack frame and return to the caller.  */
        !           782:   FUNCTION_EPILOGUE (file, get_frame_size ());
        !           783: #endif
        !           784: 
        !           785: #ifdef SDB_DEBUGGING_INFO
        !           786:   if (write_symbols == SDB_DEBUG)
        !           787:     sdbout_end_epilogue ();
        !           788: #endif
        !           789: 
        !           790: #ifdef DWARF_DEBUGGING_INFO
        !           791:   if (write_symbols == DWARF_DEBUG)
        !           792:     dwarfout_end_epilogue ();
        !           793: #endif
        !           794: 
        !           795:   /* If FUNCTION_EPILOGUE is not defined, then the function body
        !           796:      itself contains return instructions wherever needed.  */
        !           797: }
        !           798: 
        !           799: /* Output assembler code for some insns: all or part of a function.
        !           800:    For description of args, see `final_start_function', above.
        !           801: 
        !           802:    PRESCAN is 1 if we are not really outputting,
        !           803:      just scanning as if we were outputting.
        !           804:    Prescanning deletes and rearranges insns just like ordinary output.
        !           805:    PRESCAN is -2 if we are outputting after having prescanned.
        !           806:    In this case, don't try to delete or rearrange insns
        !           807:    because that has already been done.
        !           808:    Prescanning is done only on certain machines.  */
        !           809: 
        !           810: void
        !           811: final (first, file, optimize, prescan)
        !           812:      rtx first;
        !           813:      FILE *file;
        !           814:      int optimize;
        !           815:      int prescan;
        !           816: {
        !           817:   register rtx insn;
        !           818:   int max_line = 0;
        !           819: 
        !           820:   last_ignored_compare = 0;
        !           821:   new_block = 1;
        !           822: 
        !           823:   /* Make a map indicating which line numbers appear in this function.  */
        !           824:   for (insn = first; insn; insn = NEXT_INSN (insn))
        !           825:     if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > max_line)
        !           826:       max_line = NOTE_LINE_NUMBER (insn);
        !           827: 
        !           828:   line_note_exists = (char *) oballoc (max_line + 1);
        !           829:   bzero (line_note_exists, max_line + 1);
        !           830: 
        !           831:   for (insn = first; insn; insn = NEXT_INSN (insn))
        !           832:     if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
        !           833:       line_note_exists[NOTE_LINE_NUMBER (insn)] = 1;
        !           834: 
        !           835:   init_recog ();
        !           836: 
        !           837:   CC_STATUS_INIT;
        !           838: 
        !           839:   /* Output the insns.  */
        !           840:   for (insn = NEXT_INSN (first); insn;)
        !           841:     insn = final_scan_insn (insn, file, optimize, prescan, 0);
        !           842: 
        !           843:   /* Do basic-block profiling here
        !           844:      if the last insn was a conditional branch.  */
        !           845:   if (profile_block_flag && new_block)
        !           846:     {
        !           847:       new_block = 0;
        !           848:       /* Enable the table of basic-block use counts
        !           849:         to point at the code it applies to.  */
        !           850:       ASM_OUTPUT_INTERNAL_LABEL (file, "LPB", count_basic_blocks);
        !           851:       /* Before first insn of this basic block, increment the
        !           852:         count of times it was entered.  */
        !           853: #ifdef BLOCK_PROFILER
        !           854:       BLOCK_PROFILER (file, count_basic_blocks);
        !           855:       CC_STATUS_INIT;
        !           856: #endif
        !           857:       count_basic_blocks++;
        !           858:     }
        !           859: }
        !           860: 
        !           861: /* The final scan for one insn, INSN.
        !           862:    Args are same as in `final', except that INSN
        !           863:    is the insn being scanned.
        !           864:    Value returned is the next insn to be scanned.
        !           865: 
        !           866:    NOPEEPHOLES is the flag to disallow peephole processing (currently
        !           867:    used for within delayed branch sequence output).  */
        !           868: 
        !           869: rtx
        !           870: final_scan_insn (insn, file, optimize, prescan, nopeepholes)
        !           871:      rtx insn;
        !           872:      FILE *file;
        !           873:      int optimize;
        !           874:      int prescan;
        !           875:      int nopeepholes;
        !           876: {
        !           877:   register int i;
        !           878:   insn_counter++;
        !           879: 
        !           880:   /* Ignore deleted insns.  These can occur when we split insns (due to a
        !           881:      template of "#") while not optimizing.  */
        !           882:   if (INSN_DELETED_P (insn))
        !           883:     return NEXT_INSN (insn);
        !           884: 
        !           885:   switch (GET_CODE (insn))
        !           886:     {
        !           887:     case NOTE:
        !           888:       if (prescan > 0)
        !           889:        break;
        !           890: 
        !           891:       /* Align the beginning of a loop, for higher speed
        !           892:         on certain machines.  */
        !           893: 
        !           894:       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG && optimize > 0)
        !           895:        {
        !           896: #ifdef ASM_OUTPUT_LOOP_ALIGN
        !           897:          rtx next = next_nonnote_insn (insn);
        !           898:          if (next && GET_CODE (next) == CODE_LABEL)
        !           899:            {
        !           900:              ASM_OUTPUT_LOOP_ALIGN (asm_out_file);
        !           901:            }
        !           902: #endif
        !           903:          break;
        !           904:        }
        !           905:       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END)
        !           906:        break;
        !           907: 
        !           908:       if (write_symbols == NO_DEBUG)
        !           909:        break;
        !           910:       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG)
        !           911:        {
        !           912: #ifdef SDB_DEBUGGING_INFO
        !           913:          if (write_symbols == SDB_DEBUG)
        !           914:            sdbout_begin_function (last_linenum);
        !           915: #endif
        !           916:          break;
        !           917:        }
        !           918:       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED)
        !           919:        break;                  /* An insn that was "deleted" */
        !           920:       if (app_on)
        !           921:        {
        !           922:          fprintf (file, ASM_APP_OFF);
        !           923:          app_on = 0;
        !           924:        }
        !           925:       if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG
        !           926:          && (debug_info_level == DINFO_LEVEL_NORMAL
        !           927:              || debug_info_level == DINFO_LEVEL_VERBOSE))
        !           928:        {
        !           929:          /* Beginning of a symbol-block.  Assign it a sequence number
        !           930:             and push the number onto the stack PENDING_BLOCKS.  */
        !           931: 
        !           932:          if (block_depth == max_block_depth)
        !           933:            {
        !           934:              /* PENDING_BLOCKS is full; make it longer.  */
        !           935:              max_block_depth *= 2;
        !           936:              pending_blocks
        !           937:                = (int *) xrealloc (pending_blocks,
        !           938:                                    max_block_depth * sizeof (int));
        !           939:            }
        !           940:          pending_blocks[block_depth++] = next_block_index;
        !           941: 
        !           942:          /* Output debugging info about the symbol-block beginning.  */
        !           943: 
        !           944: #ifdef SDB_DEBUGGING_INFO
        !           945:          if (write_symbols == SDB_DEBUG)
        !           946:            sdbout_begin_block (file, last_linenum, next_block_index);
        !           947: #endif
        !           948: #ifdef DBX_DEBUGGING_INFO
        !           949:          if (write_symbols == DBX_DEBUG)
        !           950:            ASM_OUTPUT_INTERNAL_LABEL (file, "LBB", next_block_index);
        !           951: #endif
        !           952: #ifdef DWARF_DEBUGGING_INFO
        !           953:          if (write_symbols == DWARF_DEBUG && block_depth > 1)
        !           954:            dwarfout_begin_block (next_block_index);
        !           955: #endif
        !           956: 
        !           957:          next_block_index++;
        !           958:        }
        !           959:       else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END
        !           960:               && (debug_info_level == DINFO_LEVEL_NORMAL
        !           961:                   || debug_info_level == DINFO_LEVEL_VERBOSE))
        !           962:        {
        !           963:          /* End of a symbol-block.  Pop its sequence number off
        !           964:             PENDING_BLOCKS and output debugging info based on that.  */
        !           965: 
        !           966:          --block_depth;
        !           967: 
        !           968: #ifdef DBX_DEBUGGING_INFO
        !           969:          if (write_symbols == DBX_DEBUG && block_depth >= 0)
        !           970:            ASM_OUTPUT_INTERNAL_LABEL (file, "LBE",
        !           971:                                       pending_blocks[block_depth]);
        !           972: #endif
        !           973: #ifdef SDB_DEBUGGING_INFO
        !           974:          if (write_symbols == SDB_DEBUG && block_depth >= 0)
        !           975:            sdbout_end_block (file, last_linenum);
        !           976: #endif
        !           977: #ifdef DWARF_DEBUGGING_INFO
        !           978:          if (write_symbols == DWARF_DEBUG && block_depth >= 1)
        !           979:            dwarfout_end_block (pending_blocks[block_depth]);
        !           980: #endif
        !           981:        }
        !           982:       else if (NOTE_LINE_NUMBER (insn) > 0)
        !           983:        /* This note is a line-number.  */
        !           984:        {
        !           985:          register rtx note;
        !           986: 
        !           987: #if 0 /* This is what we used to do.  */
        !           988:          output_source_line (file, insn);
        !           989: #endif
        !           990:          int note_after = 0;
        !           991: 
        !           992:          /* If there is anything real after this note,
        !           993:             output it.  If another line note follows, omit this one.  */
        !           994:          for (note = NEXT_INSN (insn); note; note = NEXT_INSN (note))
        !           995:            {
        !           996:              if (GET_CODE (note) != NOTE && GET_CODE (note) != CODE_LABEL)
        !           997:                break;
        !           998:              else if (GET_CODE (note) == NOTE && NOTE_LINE_NUMBER (note) > 0)
        !           999:                {
        !          1000:                  /* Another note follows; we can delete this note provided
        !          1001:                     no intervening line numbers have notes elsewhere.  */
        !          1002:                  int num;
        !          1003:                  for (num = NOTE_LINE_NUMBER (insn) + 1;
        !          1004:                       num < NOTE_LINE_NUMBER (note);
        !          1005:                       num++)
        !          1006:                    if (line_note_exists[num])
        !          1007:                      break;
        !          1008: 
        !          1009:                  if (num == NOTE_LINE_NUMBER (note))
        !          1010:                    note_after = 1;
        !          1011:                  break;
        !          1012:                }
        !          1013:            }
        !          1014: 
        !          1015:          /* Output this line note
        !          1016:             if it is the first or the last line note in a row.  */
        !          1017:          if (!note_after)
        !          1018:            output_source_line (file, insn);
        !          1019:        }
        !          1020:       break;
        !          1021: 
        !          1022:     case BARRIER:
        !          1023: #ifdef ASM_OUTPUT_ALIGN_CODE
        !          1024:       ASM_OUTPUT_ALIGN_CODE (file);
        !          1025: #endif
        !          1026:       break;
        !          1027: 
        !          1028:     case CODE_LABEL:
        !          1029:       CC_STATUS_INIT;
        !          1030:       if (prescan > 0)
        !          1031:        break;
        !          1032:       new_block = 1;
        !          1033: #ifdef SDB_DEBUGGING_INFO
        !          1034:       if (write_symbols == SDB_DEBUG && LABEL_NAME (insn))
        !          1035:        sdbout_label (insn);
        !          1036: #endif
        !          1037: #ifdef DWARF_DEBUGGING_INFO
        !          1038:       if (write_symbols == DWARF_DEBUG && LABEL_NAME (insn))
        !          1039:        dwarfout_label (insn);
        !          1040: #endif
        !          1041:       if (app_on)
        !          1042:        {
        !          1043:          fprintf (file, ASM_APP_OFF);
        !          1044:          app_on = 0;
        !          1045:        }
        !          1046:       if (NEXT_INSN (insn) != 0
        !          1047:          && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN)
        !          1048:        {
        !          1049:          rtx nextbody = PATTERN (NEXT_INSN (insn));
        !          1050: 
        !          1051:          /* If this label is followed by a jump-table,
        !          1052:             make sure we put the label in the read-only section.  Also
        !          1053:             possibly write the label and jump table together.  */
        !          1054: 
        !          1055:          if (GET_CODE (nextbody) == ADDR_VEC
        !          1056:              || GET_CODE (nextbody) == ADDR_DIFF_VEC)
        !          1057:            {
        !          1058: #ifndef JUMP_TABLES_IN_TEXT_SECTION
        !          1059:              readonly_data_section ();
        !          1060: #else
        !          1061:              text_section ();
        !          1062: #endif
        !          1063: #ifdef ASM_OUTPUT_CASE_LABEL
        !          1064:              ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
        !          1065:                                     NEXT_INSN (insn));
        !          1066: #else
        !          1067:              ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
        !          1068: #endif
        !          1069:              break;
        !          1070:            }
        !          1071:        }
        !          1072: 
        !          1073:       ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
        !          1074:       break;
        !          1075: 
        !          1076:     default:
        !          1077:       {
        !          1078:        register rtx body = PATTERN (insn);
        !          1079:        int insn_code_number;
        !          1080:        char *template;
        !          1081:        rtx note;
        !          1082: 
        !          1083:        /* An INSN, JUMP_INSN or CALL_INSN.
        !          1084:           First check for special kinds that recog doesn't recognize.  */
        !          1085: 
        !          1086:        if (GET_CODE (body) == USE /* These are just declarations */
        !          1087:            || GET_CODE (body) == CLOBBER)
        !          1088:          break;
        !          1089: 
        !          1090: #ifdef HAVE_cc0
        !          1091:        /* If there is a REG_CC_SETTER note on this insn, it means that
        !          1092:           the setting of the condition code was done in the delay slot
        !          1093:           of the insn that branched here.  So recover the cc status
        !          1094:           from the insn that set it.  */
        !          1095: 
        !          1096:        note = find_reg_note (insn, REG_CC_SETTER, 0);
        !          1097:        if (note)
        !          1098:          {
        !          1099:            NOTICE_UPDATE_CC (PATTERN (XEXP (note, 0)), XEXP (note, 0));
        !          1100:            cc_prev_status = cc_status;
        !          1101:          }
        !          1102: #endif
        !          1103: 
        !          1104:        /* Detect insns that are really jump-tables
        !          1105:           and output them as such.  */
        !          1106: 
        !          1107:        if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
        !          1108:          {
        !          1109:            register int vlen, idx;
        !          1110: 
        !          1111:            if (prescan > 0)
        !          1112:              break;
        !          1113: 
        !          1114:            if (app_on)
        !          1115:              {
        !          1116:                fprintf (file, ASM_APP_OFF);
        !          1117:                app_on = 0;
        !          1118:              }
        !          1119: 
        !          1120:            vlen = XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC);
        !          1121:            for (idx = 0; idx < vlen; idx++)
        !          1122:              {
        !          1123:                if (GET_CODE (body) == ADDR_VEC)
        !          1124:                  ASM_OUTPUT_ADDR_VEC_ELT
        !          1125:                    (file, CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 0, idx), 0)));
        !          1126:                else
        !          1127:                  ASM_OUTPUT_ADDR_DIFF_ELT
        !          1128:                    (file,
        !          1129:                     CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 1, idx), 0)),
        !          1130:                     CODE_LABEL_NUMBER (XEXP (XEXP (body, 0), 0)));
        !          1131:              }
        !          1132: #ifdef ASM_OUTPUT_CASE_END
        !          1133:            ASM_OUTPUT_CASE_END (file,
        !          1134:                                 CODE_LABEL_NUMBER (PREV_INSN (insn)),
        !          1135:                                 insn);
        !          1136: #endif
        !          1137: 
        !          1138:            text_section ();
        !          1139: 
        !          1140:            break;
        !          1141:          }
        !          1142: 
        !          1143:        /* Do basic-block profiling when we reach a new block.
        !          1144:           Done here to avoid jump tables.  */
        !          1145:        if (profile_block_flag && new_block)
        !          1146:          {
        !          1147:            new_block = 0;
        !          1148:            /* Enable the table of basic-block use counts
        !          1149:               to point at the code it applies to.  */
        !          1150:            ASM_OUTPUT_INTERNAL_LABEL (file, "LPB", count_basic_blocks);
        !          1151:            /* Before first insn of this basic block, increment the
        !          1152:               count of times it was entered.  */
        !          1153: #ifdef BLOCK_PROFILER
        !          1154:            BLOCK_PROFILER (file, count_basic_blocks);
        !          1155:            CC_STATUS_INIT;
        !          1156: #endif
        !          1157:            count_basic_blocks++;
        !          1158:          }
        !          1159: 
        !          1160:        if (GET_CODE (body) == ASM_INPUT)
        !          1161:          {
        !          1162:            /* There's no telling what that did to the condition codes.  */
        !          1163:            CC_STATUS_INIT;
        !          1164:            if (prescan > 0)
        !          1165:              break;
        !          1166:            if (! app_on)
        !          1167:              {
        !          1168:                fprintf (file, ASM_APP_ON);
        !          1169:                app_on = 1;
        !          1170:              }
        !          1171:            fprintf (asm_out_file, "\t%s\n", XSTR (body, 0));
        !          1172:            break;
        !          1173:          }
        !          1174: 
        !          1175:        /* Detect `asm' construct with operands.  */
        !          1176:        if (asm_noperands (body) >= 0)
        !          1177:          {
        !          1178:            int noperands = asm_noperands (body);
        !          1179:            rtx *ops;
        !          1180:            char *string;
        !          1181: 
        !          1182:            /* There's no telling what that did to the condition codes.  */
        !          1183:            CC_STATUS_INIT;
        !          1184:            if (prescan > 0)
        !          1185:              break;
        !          1186: 
        !          1187:            /* alloca won't do here, since only return from `final'
        !          1188:               would free it.  */
        !          1189:            if (noperands > 0)
        !          1190:              ops = (rtx *) xmalloc (noperands * sizeof (rtx));
        !          1191: 
        !          1192:            if (! app_on)
        !          1193:              {
        !          1194:                fprintf (file, ASM_APP_ON);
        !          1195:                app_on = 1;
        !          1196:              }
        !          1197: 
        !          1198:            /* Get out the operand values.  */
        !          1199:            string = decode_asm_operands (body, ops, 0, 0, 0);
        !          1200:            /* Inhibit aborts on what would otherwise be compiler bugs.  */
        !          1201:            insn_noperands = noperands;
        !          1202:            this_is_asm_operands = insn;
        !          1203:            /* Output the insn using them.  */
        !          1204:            output_asm_insn (string, ops);
        !          1205:            this_is_asm_operands = 0;
        !          1206:            if (noperands > 0)
        !          1207:              free (ops);
        !          1208:            break;
        !          1209:          }
        !          1210: 
        !          1211:        if (prescan <= 0 && app_on)
        !          1212:          {
        !          1213:            fprintf (file, ASM_APP_OFF);
        !          1214:            app_on = 0;
        !          1215:          }
        !          1216: 
        !          1217:        if (GET_CODE (body) == SEQUENCE)
        !          1218:          {
        !          1219:            /* A delayed-branch sequence */
        !          1220:            register int i;
        !          1221:            rtx next;
        !          1222: 
        !          1223:            if (prescan > 0)
        !          1224:              break;
        !          1225:            final_sequence = body;
        !          1226: 
        !          1227:            /* The first insn in this SEQUENCE might be a JUMP_INSN that will
        !          1228:               force the restoration of a comparison that was previously
        !          1229:               thought unnecessary.  If that happens, cancel this sequence
        !          1230:               and cause that insn to be restored.  */
        !          1231: 
        !          1232:            next = final_scan_insn (XVECEXP (body, 0, 0), file, 0, prescan, 1);
        !          1233:            if (next != XVECEXP (body, 0, 1))
        !          1234:              {
        !          1235:                final_sequence = 0;
        !          1236:                return next;
        !          1237:              }
        !          1238: 
        !          1239:            for (i = 1; i < XVECLEN (body, 0); i++)
        !          1240:              final_scan_insn (XVECEXP (body, 0, i), file, 0, prescan, 1);
        !          1241: #ifdef DBR_OUTPUT_SEQEND
        !          1242:            DBR_OUTPUT_SEQEND (file);
        !          1243: #endif
        !          1244:            final_sequence = 0;
        !          1245: 
        !          1246:            /* If the insn requiring the delay slot was a CALL_INSN, the
        !          1247:               insns in the delay slot are actually executed before the
        !          1248:               called function.  Hence we don't preserve any CC-setting
        !          1249:               actions in these insns and the CC must be marked as being
        !          1250:               clobbered by the function.  */
        !          1251:            if (GET_CODE (XVECEXP (body, 0, 0)) == CALL_INSN)
        !          1252:              CC_STATUS_INIT;
        !          1253:            break;
        !          1254:          }
        !          1255: 
        !          1256:        /* We have a real machine instruction as rtl.  */
        !          1257: 
        !          1258:        body = PATTERN (insn);
        !          1259: 
        !          1260: #ifdef HAVE_cc0
        !          1261:        /* Check for redundant test and compare instructions
        !          1262:           (when the condition codes are already set up as desired).
        !          1263:           This is done only when optimizing; if not optimizing,
        !          1264:           it should be possible for the user to alter a variable
        !          1265:           with the debugger in between statements
        !          1266:           and the next statement should reexamine the variable
        !          1267:           to compute the condition codes.  */
        !          1268: 
        !          1269:        if (optimize
        !          1270:            && GET_CODE (body) == SET
        !          1271:            && GET_CODE (SET_DEST (body)) == CC0
        !          1272:            && insn != last_ignored_compare)
        !          1273:          {
        !          1274:            if (GET_CODE (SET_SRC (body)) == SUBREG)
        !          1275:              SET_SRC (body) = alter_subreg (SET_SRC (body));
        !          1276:            else if (GET_CODE (SET_SRC (body)) == COMPARE)
        !          1277:              {
        !          1278:                if (GET_CODE (XEXP (SET_SRC (body), 0)) == SUBREG)
        !          1279:                  XEXP (SET_SRC (body), 0)
        !          1280:                    = alter_subreg (XEXP (SET_SRC (body), 0));
        !          1281:                if (GET_CODE (XEXP (SET_SRC (body), 1)) == SUBREG)
        !          1282:                  XEXP (SET_SRC (body), 1)
        !          1283:                    = alter_subreg (XEXP (SET_SRC (body), 1));
        !          1284:              }
        !          1285:            if ((cc_status.value1 != 0
        !          1286:                 && rtx_equal_p (SET_SRC (body), cc_status.value1))
        !          1287:                || (cc_status.value2 != 0
        !          1288:                    && rtx_equal_p (SET_SRC (body), cc_status.value2)))
        !          1289:              {
        !          1290:                /* Don't delete insn if it has an addressing side-effect.  */
        !          1291:                if (! FIND_REG_INC_NOTE (insn, 0)
        !          1292:                    /* or if anything in it is volatile.  */
        !          1293:                    && ! volatile_refs_p (PATTERN (insn)))
        !          1294:                  {
        !          1295:                    /* We don't really delete the insn; just ignore it.  */
        !          1296:                    last_ignored_compare = insn;
        !          1297:                    break;
        !          1298:                  }
        !          1299:              }
        !          1300:          }
        !          1301: #endif
        !          1302: 
        !          1303:        /* Following a conditional branch, we have a new basic block.  */
        !          1304:        if ((GET_CODE (insn) == JUMP_INSN && GET_CODE (body) == SET
        !          1305:             && GET_CODE (SET_SRC (body)) != LABEL_REF)
        !          1306:            || (GET_CODE (insn) == JUMP_INSN && GET_CODE (body) == PARALLEL
        !          1307:                && GET_CODE (XVECEXP (body, 0, 0)) == SET
        !          1308:                && GET_CODE (SET_SRC (XVECEXP (body, 0, 0))) != LABEL_REF))
        !          1309:          new_block = 1;
        !          1310: 
        !          1311: #ifndef STACK_REGS
        !          1312:        /* Don't bother outputting obvious no-ops, even without -O.
        !          1313:           This optimization is fast and doesn't interfere with debugging.
        !          1314:           Don't do this if the insn is in a delay slot, since this
        !          1315:           will cause an improper number of delay insns to be written.  */
        !          1316:        if (final_sequence == 0
        !          1317:            && prescan >= 0
        !          1318:            && GET_CODE (insn) == INSN && GET_CODE (body) == SET
        !          1319:            && GET_CODE (SET_SRC (body)) == REG
        !          1320:            && GET_CODE (SET_DEST (body)) == REG
        !          1321:            && REGNO (SET_SRC (body)) == REGNO (SET_DEST (body)))
        !          1322:          break;
        !          1323: #endif
        !          1324: 
        !          1325: #ifdef HAVE_cc0
        !          1326:        /* If this is a conditional branch, maybe modify it
        !          1327:           if the cc's are in a nonstandard state
        !          1328:           so that it accomplishes the same thing that it would
        !          1329:           do straightforwardly if the cc's were set up normally.  */
        !          1330: 
        !          1331:        if (cc_status.flags != 0
        !          1332:            && GET_CODE (insn) == JUMP_INSN
        !          1333:            && GET_CODE (body) == SET
        !          1334:            && SET_DEST (body) == pc_rtx
        !          1335:            && GET_CODE (SET_SRC (body)) == IF_THEN_ELSE
        !          1336:            /* This is done during prescan; it is not done again
        !          1337:               in final scan when prescan has been done.  */
        !          1338:            && prescan >= 0)
        !          1339:          {
        !          1340:            /* This function may alter the contents of its argument
        !          1341:               and clear some of the cc_status.flags bits.
        !          1342:               It may also return 1 meaning condition now always true
        !          1343:               or -1 meaning condition now always false
        !          1344:               or 2 meaning condition nontrivial but altered.  */
        !          1345:            register int result = alter_cond (XEXP (SET_SRC (body), 0));
        !          1346:            /* If condition now has fixed value, replace the IF_THEN_ELSE
        !          1347:               with its then-operand or its else-operand.  */
        !          1348:            if (result == 1)
        !          1349:              SET_SRC (body) = XEXP (SET_SRC (body), 1);
        !          1350:            if (result == -1)
        !          1351:              SET_SRC (body) = XEXP (SET_SRC (body), 2);
        !          1352: 
        !          1353:            /* The jump is now either unconditional or a no-op.
        !          1354:               If it has become a no-op, don't try to output it.
        !          1355:               (It would not be recognized.)  */
        !          1356:            if (SET_SRC (body) == pc_rtx)
        !          1357:              {
        !          1358:                PUT_CODE (insn, NOTE);
        !          1359:                NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
        !          1360:                NOTE_SOURCE_FILE (insn) = 0;
        !          1361:                break;
        !          1362:              }
        !          1363:            else if (GET_CODE (SET_SRC (body)) == RETURN)
        !          1364:              /* Replace (set (pc) (return)) with (return).  */
        !          1365:              PATTERN (insn) = body = SET_SRC (body);
        !          1366: 
        !          1367:            /* Rerecognize the instruction if it has changed.  */
        !          1368:            if (result != 0)
        !          1369:              INSN_CODE (insn) = -1;
        !          1370:          }
        !          1371: 
        !          1372:        /* Make same adjustments to instructions that examine the
        !          1373:           condition codes without jumping (if this machine has them).  */
        !          1374: 
        !          1375:        if (cc_status.flags != 0
        !          1376:            && GET_CODE (body) == SET)
        !          1377:          {
        !          1378:            switch (GET_CODE (SET_SRC (body)))
        !          1379:              {
        !          1380:              case GTU:
        !          1381:              case GT:
        !          1382:              case LTU:
        !          1383:              case LT:
        !          1384:              case GEU:
        !          1385:              case GE:
        !          1386:              case LEU:
        !          1387:              case LE:
        !          1388:              case EQ:
        !          1389:              case NE:
        !          1390:                {
        !          1391:                  register int result;
        !          1392:                  if (XEXP (SET_SRC (body), 0) != cc0_rtx)
        !          1393:                    break;
        !          1394:                  result = alter_cond (SET_SRC (body));
        !          1395:                  if (result == 1)
        !          1396:                    validate_change (insn, &SET_SRC (body), const_true_rtx, 0);
        !          1397:                  else if (result == -1)
        !          1398:                    validate_change (insn, &SET_SRC (body), const0_rtx, 0);
        !          1399:                  else if (result == 2)
        !          1400:                    INSN_CODE (insn) = -1;
        !          1401:                }
        !          1402:              }
        !          1403:          }
        !          1404: #endif
        !          1405: 
        !          1406:        /* Do machine-specific peephole optimizations if desired.  */
        !          1407: 
        !          1408:        if (optimize && !flag_no_peephole && !nopeepholes)
        !          1409:          {
        !          1410:            rtx next = peephole (insn);
        !          1411:            /* When peepholing, if there were notes within the peephole,
        !          1412:               emit them before the peephole.  */
        !          1413:            if (next != 0 && next != NEXT_INSN (insn))
        !          1414:              {
        !          1415:                rtx prev = PREV_INSN (insn);
        !          1416:                rtx note;
        !          1417: 
        !          1418:                for (note = NEXT_INSN (insn); note != next;
        !          1419:                     note = NEXT_INSN (note))
        !          1420:                  final_scan_insn (note, file, optimize, prescan, nopeepholes);
        !          1421: 
        !          1422:                /* In case this is prescan, put the notes
        !          1423:                   in proper position for later rescan.  */
        !          1424:                note = NEXT_INSN (insn);
        !          1425:                PREV_INSN (note) = prev;
        !          1426:                NEXT_INSN (prev) = note;
        !          1427:                NEXT_INSN (PREV_INSN (next)) = insn;
        !          1428:                PREV_INSN (insn) = PREV_INSN (next);
        !          1429:                NEXT_INSN (insn) = next;
        !          1430:                PREV_INSN (next) = insn;
        !          1431:              }
        !          1432: 
        !          1433:            /* PEEPHOLE might have changed this.  */
        !          1434:            body = PATTERN (insn);
        !          1435:          }
        !          1436: 
        !          1437:        /* Try to recognize the instruction.
        !          1438:           If successful, verify that the operands satisfy the
        !          1439:           constraints for the instruction.  Crash if they don't,
        !          1440:           since `reload' should have changed them so that they do.  */
        !          1441: 
        !          1442:        insn_code_number = recog_memoized (insn);
        !          1443:        insn_extract (insn);
        !          1444:        for (i = 0; i < insn_n_operands[insn_code_number]; i++)
        !          1445:          {
        !          1446:            if (GET_CODE (recog_operand[i]) == SUBREG)
        !          1447:              recog_operand[i] = alter_subreg (recog_operand[i]);
        !          1448:          }
        !          1449: 
        !          1450: #ifdef REGISTER_CONSTRAINTS
        !          1451:        if (! constrain_operands (insn_code_number, 1))
        !          1452:          fatal_insn_not_found (insn);
        !          1453: #endif
        !          1454: 
        !          1455:        /* Some target machines need to prescan each insn before
        !          1456:           it is output.  */
        !          1457: 
        !          1458: #ifdef FINAL_PRESCAN_INSN
        !          1459:        FINAL_PRESCAN_INSN (insn, recog_operand,
        !          1460:                            insn_n_operands[insn_code_number]);
        !          1461: #endif
        !          1462: 
        !          1463: #ifdef HAVE_cc0
        !          1464:        cc_prev_status = cc_status;
        !          1465: 
        !          1466:        /* Update `cc_status' for this instruction.
        !          1467:           The instruction's output routine may change it further.
        !          1468:           If the output routine for a jump insn needs to depend
        !          1469:           on the cc status, it should look at cc_prev_status.  */
        !          1470: 
        !          1471:        NOTICE_UPDATE_CC (body, insn);
        !          1472: #endif
        !          1473: 
        !          1474:        debug_insn = insn;
        !          1475: 
        !          1476:        /* If the proper template needs to be chosen by some C code,
        !          1477:           run that code and get the real template.  */
        !          1478: 
        !          1479:        template = insn_template[insn_code_number];
        !          1480:        if (template == 0)
        !          1481:          {
        !          1482:            template = (*insn_outfun[insn_code_number]) (recog_operand, insn);
        !          1483: 
        !          1484:            /* If the C code returns 0, it means that it is a jump insn
        !          1485:               which follows a deleted test insn, and that test insn
        !          1486:               needs to be reinserted.  */
        !          1487:            if (template == 0)
        !          1488:              {
        !          1489:                if (prev_nonnote_insn (insn) != last_ignored_compare)
        !          1490:                  abort ();
        !          1491:                new_block = 0;
        !          1492:                return prev_nonnote_insn (insn);
        !          1493:              }
        !          1494:          }
        !          1495: 
        !          1496:        /* If the template is the string "#", it means that this insn must
        !          1497:           be split.  */
        !          1498:        if (template[0] == '#' && template[1] == '\0')
        !          1499:          {
        !          1500:            rtx new = try_split (body, insn, 0);
        !          1501: 
        !          1502:            /* If we didn't split the insn, go away.  */
        !          1503:            if (new == insn && PATTERN (new) == body)
        !          1504:              abort ();
        !          1505:              
        !          1506:            new_block = 0;
        !          1507:            return new;
        !          1508:          }
        !          1509:        
        !          1510:        if (prescan > 0)
        !          1511:          break;
        !          1512: 
        !          1513:        /* Output assembler code from the template.  */
        !          1514: 
        !          1515:        output_asm_insn (template, recog_operand);
        !          1516: 
        !          1517: #if 0
        !          1518:        /* It's not at all clear why we did this and doing so interferes
        !          1519:           with tests we'd like to do to use REG_WAS_0 notes, so let's try
        !          1520:           with this out.  */
        !          1521: 
        !          1522:        /* Mark this insn as having been output.  */
        !          1523:        INSN_DELETED_P (insn) = 1;
        !          1524: #endif
        !          1525: 
        !          1526:        debug_insn = 0;
        !          1527:       }
        !          1528:     }
        !          1529:   return NEXT_INSN (insn);
        !          1530: }
        !          1531: 
        !          1532: /* Output debugging info to the assembler file FILE
        !          1533:    based on the NOTE-insn INSN, assumed to be a line number.  */
        !          1534: 
        !          1535: static void
        !          1536: output_source_line (file, insn)
        !          1537:      FILE *file;
        !          1538:      rtx insn;
        !          1539: {
        !          1540:   char ltext_label_name[100];
        !          1541:   register char *filename = NOTE_SOURCE_FILE (insn);
        !          1542: 
        !          1543:   last_linenum = NOTE_LINE_NUMBER (insn);
        !          1544: 
        !          1545:   if (write_symbols != NO_DEBUG)
        !          1546:     {
        !          1547: #ifdef SDB_DEBUGGING_INFO
        !          1548:       if (write_symbols == SDB_DEBUG
        !          1549: #if 0 /* People like having line numbers even in wrong file!  */
        !          1550:          /* COFF can't handle multiple source files--lose, lose.  */
        !          1551:          && !strcmp (filename, main_input_filename)
        !          1552: #endif
        !          1553:          /* COFF relative line numbers must be positive.  */
        !          1554:          && last_linenum > sdb_begin_function_line)
        !          1555:        {
        !          1556: #ifdef ASM_OUTPUT_SOURCE_LINE
        !          1557:          ASM_OUTPUT_SOURCE_LINE (file, last_linenum);
        !          1558: #else
        !          1559:          fprintf (file, "\t.ln\t%d\n",
        !          1560:                   ((sdb_begin_function_line > -1)
        !          1561:                    ? last_linenum - sdb_begin_function_line : 1));
        !          1562: #endif
        !          1563:        }
        !          1564: #endif
        !          1565: 
        !          1566: #ifdef DBX_DEBUGGING_INFO
        !          1567:       if (write_symbols == DBX_DEBUG)
        !          1568:        {
        !          1569:          dbxout_source_file (file, filename);
        !          1570: 
        !          1571: #ifdef ASM_OUTPUT_SOURCE_LINE
        !          1572:          ASM_OUTPUT_SOURCE_LINE (file, NOTE_LINE_NUMBER (insn));
        !          1573: #else
        !          1574:          fprintf (file, "\t%s %d,0,%d\n", ASM_STABD_OP, 
        !          1575:                   N_SLINE, NOTE_LINE_NUMBER (insn));
        !          1576: #endif
        !          1577:        }
        !          1578: #endif /* DBX_DEBUGGING_INFO */
        !          1579: 
        !          1580: #ifdef DWARF_DEBUGGING_INFO
        !          1581:       if (write_symbols == DWARF_DEBUG)
        !          1582:        dwarfout_line (filename, NOTE_LINE_NUMBER (insn));
        !          1583: #endif
        !          1584:     }
        !          1585: }
        !          1586: 
        !          1587: /* If X is a SUBREG, replace it with a REG or a MEM,
        !          1588:    based on the thing it is a subreg of.  */
        !          1589: 
        !          1590: rtx
        !          1591: alter_subreg (x)
        !          1592:      register rtx x;
        !          1593: {
        !          1594:   register rtx y = SUBREG_REG (x);
        !          1595:   if (GET_CODE (y) == SUBREG)
        !          1596:     y = alter_subreg (y);
        !          1597: 
        !          1598:   if (GET_CODE (y) == REG)
        !          1599:     {
        !          1600:       /* If the containing reg really gets a hard reg, so do we.  */
        !          1601:       PUT_CODE (x, REG);
        !          1602:       REGNO (x) = REGNO (y) + SUBREG_WORD (x);
        !          1603:     }
        !          1604:   else if (GET_CODE (y) == MEM)
        !          1605:     {
        !          1606:       register int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
        !          1607: #if BYTES_BIG_ENDIAN
        !          1608:       offset -= (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (x)))
        !          1609:                 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (y))));
        !          1610: #endif
        !          1611:       PUT_CODE (x, MEM);
        !          1612:       MEM_VOLATILE_P (x) = MEM_VOLATILE_P (y);
        !          1613:       XEXP (x, 0) = plus_constant (XEXP (y, 0), offset);
        !          1614:     }
        !          1615: 
        !          1616:   return x;
        !          1617: }
        !          1618: 
        !          1619: /* Do alter_subreg on all the SUBREGs contained in X.  */
        !          1620: 
        !          1621: static rtx
        !          1622: walk_alter_subreg (x)
        !          1623:      rtx x;
        !          1624: {
        !          1625:   switch (GET_CODE (x))
        !          1626:     {
        !          1627:     case PLUS:
        !          1628:     case MULT:
        !          1629:       XEXP (x, 0) = walk_alter_subreg (XEXP (x, 0));
        !          1630:       XEXP (x, 1) = walk_alter_subreg (XEXP (x, 1));
        !          1631:       break;
        !          1632: 
        !          1633:     case MEM:
        !          1634:       XEXP (x, 0) = walk_alter_subreg (XEXP (x, 0));
        !          1635:       break;
        !          1636: 
        !          1637:     case SUBREG:
        !          1638:       return alter_subreg (x);
        !          1639:     }
        !          1640: 
        !          1641:   return x;
        !          1642: }
        !          1643: 
        !          1644: #ifdef HAVE_cc0
        !          1645: 
        !          1646: /* Given BODY, the body of a jump instruction, alter the jump condition
        !          1647:    as required by the bits that are set in cc_status.flags.
        !          1648:    Not all of the bits there can be handled at this level in all cases.
        !          1649: 
        !          1650:    The value is normally 0.
        !          1651:    1 means that the condition has become always true.
        !          1652:    -1 means that the condition has become always false.
        !          1653:    2 means that COND has been altered.  */
        !          1654: 
        !          1655: static int
        !          1656: alter_cond (cond)
        !          1657:      register rtx cond;
        !          1658: {
        !          1659:   int value = 0;
        !          1660: 
        !          1661:   if (cc_status.flags & CC_REVERSED)
        !          1662:     {
        !          1663:       value = 2;
        !          1664:       PUT_CODE (cond, swap_condition (GET_CODE (cond)));
        !          1665:     }
        !          1666: 
        !          1667:   if (cc_status.flags & CC_INVERTED)
        !          1668:     {
        !          1669:       value = 2;
        !          1670:       PUT_CODE (cond, reverse_condition (GET_CODE (cond)));
        !          1671:     }
        !          1672: 
        !          1673:   if (cc_status.flags & CC_NOT_POSITIVE)
        !          1674:     switch (GET_CODE (cond))
        !          1675:       {
        !          1676:       case LE:
        !          1677:       case LEU:
        !          1678:       case GEU:
        !          1679:        /* Jump becomes unconditional.  */
        !          1680:        return 1;
        !          1681: 
        !          1682:       case GT:
        !          1683:       case GTU:
        !          1684:       case LTU:
        !          1685:        /* Jump becomes no-op.  */
        !          1686:        return -1;
        !          1687: 
        !          1688:       case GE:
        !          1689:        PUT_CODE (cond, EQ);
        !          1690:        value = 2;
        !          1691:        break;
        !          1692: 
        !          1693:       case LT:
        !          1694:        PUT_CODE (cond, NE);
        !          1695:        value = 2;
        !          1696:        break;
        !          1697:       }
        !          1698: 
        !          1699:   if (cc_status.flags & CC_NOT_NEGATIVE)
        !          1700:     switch (GET_CODE (cond))
        !          1701:       {
        !          1702:       case GE:
        !          1703:       case GEU:
        !          1704:        /* Jump becomes unconditional.  */
        !          1705:        return 1;
        !          1706: 
        !          1707:       case LT:
        !          1708:       case LTU:
        !          1709:        /* Jump becomes no-op.  */
        !          1710:        return -1;
        !          1711: 
        !          1712:       case LE:
        !          1713:       case LEU:
        !          1714:        PUT_CODE (cond, EQ);
        !          1715:        value = 2;
        !          1716:        break;
        !          1717: 
        !          1718:       case GT:
        !          1719:       case GTU:
        !          1720:        PUT_CODE (cond, NE);
        !          1721:        value = 2;
        !          1722:        break;
        !          1723:       }
        !          1724: 
        !          1725:   if (cc_status.flags & CC_NO_OVERFLOW)
        !          1726:     switch (GET_CODE (cond))
        !          1727:       {
        !          1728:       case GEU:
        !          1729:        /* Jump becomes unconditional.  */
        !          1730:        return 1;
        !          1731: 
        !          1732:       case LEU:
        !          1733:        PUT_CODE (cond, EQ);
        !          1734:        value = 2;
        !          1735:        break;
        !          1736: 
        !          1737:       case GTU:
        !          1738:        PUT_CODE (cond, NE);
        !          1739:        value = 2;
        !          1740:        break;
        !          1741: 
        !          1742:       case LTU:
        !          1743:        /* Jump becomes no-op.  */
        !          1744:        return -1;
        !          1745:       }
        !          1746: 
        !          1747:   if (cc_status.flags & (CC_Z_IN_NOT_N | CC_Z_IN_N))
        !          1748:     switch (GET_CODE (cond))
        !          1749:       {
        !          1750:       case LE:
        !          1751:       case LEU:
        !          1752:       case GE:
        !          1753:       case GEU:
        !          1754:       case LT:
        !          1755:       case LTU:
        !          1756:       case GT:
        !          1757:       case GTU:
        !          1758:        abort ();
        !          1759: 
        !          1760:       case NE:
        !          1761:        PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? GE : LT);
        !          1762:        value = 2;
        !          1763:        break;
        !          1764: 
        !          1765:       case EQ:
        !          1766:        PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? LT : GE);
        !          1767:        value = 2;
        !          1768:        break;
        !          1769:       }
        !          1770:   
        !          1771:   return value;
        !          1772: }
        !          1773: #endif
        !          1774: 
        !          1775: /* Report inconsistency between the assembler template and the operands.
        !          1776:    In an `asm', it's the user's fault; otherwise, the compiler's fault.  */
        !          1777: 
        !          1778: void
        !          1779: output_operand_lossage (str)
        !          1780:      char *str;
        !          1781: {
        !          1782:   if (this_is_asm_operands)
        !          1783:     error_for_asm (this_is_asm_operands, "invalid `asm': %s", str);
        !          1784:   else
        !          1785:     abort ();
        !          1786: }
        !          1787: 
        !          1788: /* Output of assembler code from a template, and its subroutines.  */
        !          1789: 
        !          1790: /* Output text from TEMPLATE to the assembler output file,
        !          1791:    obeying %-directions to substitute operands taken from
        !          1792:    the vector OPERANDS.
        !          1793: 
        !          1794:    %N (for N a digit) means print operand N in usual manner.
        !          1795:    %lN means require operand N to be a CODE_LABEL or LABEL_REF
        !          1796:       and print the label name with no punctuation.
        !          1797:    %cN means require operand N to be a constant
        !          1798:       and print the constant expression with no punctuation.
        !          1799:    %aN means expect operand N to be a memory address
        !          1800:       (not a memory reference!) and print a reference
        !          1801:       to that address.
        !          1802:    %nN means expect operand N to be a constant
        !          1803:       and print a constant expression for minus the value
        !          1804:       of the operand, with no other punctuation.  */
        !          1805: 
        !          1806: void
        !          1807: output_asm_insn (template, operands)
        !          1808:      char *template;
        !          1809:      rtx *operands;
        !          1810: {
        !          1811:   register char *p;
        !          1812:   register int c;
        !          1813: 
        !          1814:   /* An insn may return a null string template
        !          1815:      in a case where no assembler code is needed.  */
        !          1816:   if (*template == 0)
        !          1817:     return;
        !          1818: 
        !          1819:   p = template;
        !          1820:   putc ('\t', asm_out_file);
        !          1821: 
        !          1822: #ifdef ASM_OUTPUT_OPCODE
        !          1823:   ASM_OUTPUT_OPCODE (asm_out_file, p);
        !          1824: #endif
        !          1825: 
        !          1826:   while (c = *p++)
        !          1827:     {
        !          1828: #ifdef ASM_OUTPUT_OPCODE
        !          1829:       if (c == '\n')
        !          1830:        {
        !          1831:          putc (c, asm_out_file);
        !          1832:          while ((c = *p) == '\t')
        !          1833:            {
        !          1834:              putc (c, asm_out_file);
        !          1835:              p++;
        !          1836:            }
        !          1837:          ASM_OUTPUT_OPCODE (asm_out_file, p);
        !          1838:        }
        !          1839:       else
        !          1840: #endif
        !          1841:       if (c != '%')
        !          1842:        putc (c, asm_out_file);
        !          1843:       else
        !          1844:        {
        !          1845:          /* %% outputs a single %.  */
        !          1846:          if (*p == '%')
        !          1847:            {
        !          1848:              p++;
        !          1849:              putc (c, asm_out_file);
        !          1850:            }
        !          1851:          /* %= outputs a number which is unique to each insn in the entire
        !          1852:             compilation.  This is useful for making local labels that are
        !          1853:             referred to more than once in a given insn.  */
        !          1854:          else if (*p == '=')
        !          1855:            fprintf (asm_out_file, "%d", insn_counter);
        !          1856:          /* % followed by a letter and some digits
        !          1857:             outputs an operand in a special way depending on the letter.
        !          1858:             Letters `acln' are implemented directly.
        !          1859:             Other letters are passed to `output_operand' so that
        !          1860:             the PRINT_OPERAND macro can define them.  */
        !          1861:          else if ((*p >= 'a' && *p <= 'z')
        !          1862:                   || (*p >= 'A' && *p <= 'Z'))
        !          1863:            {
        !          1864:              int letter = *p++;
        !          1865:              c = atoi (p);
        !          1866: 
        !          1867:              if (! (*p >= '0' && *p <= '9'))
        !          1868:                output_operand_lossage ("operand number missing after %-letter");
        !          1869:              else if (this_is_asm_operands && c >= (unsigned) insn_noperands)
        !          1870:                output_operand_lossage ("operand number out of range");
        !          1871:              else if (letter == 'l')
        !          1872:                output_asm_label (operands[c]);
        !          1873:              else if (letter == 'a')
        !          1874:                output_address (operands[c]);
        !          1875:              else if (letter == 'c')
        !          1876:                {
        !          1877:                  if (CONSTANT_ADDRESS_P (operands[c]))
        !          1878:                    output_addr_const (asm_out_file, operands[c]);
        !          1879:                  else
        !          1880:                    output_operand (operands[c], 'c');
        !          1881:                }
        !          1882:              else if (letter == 'n')
        !          1883:                {
        !          1884:                  if (GET_CODE (operands[c]) == CONST_INT)
        !          1885:                    fprintf (asm_out_file, "%d", - INTVAL (operands[c]));
        !          1886:                  else
        !          1887:                    {
        !          1888:                      putc ('-', asm_out_file);
        !          1889:                      output_addr_const (asm_out_file, operands[c]);
        !          1890:                    }
        !          1891:                }
        !          1892:              else
        !          1893:                output_operand (operands[c], letter);
        !          1894: 
        !          1895:              while ((c = *p) >= '0' && c <= '9') p++;
        !          1896:            }
        !          1897:          /* % followed by a digit outputs an operand the default way.  */
        !          1898:          else if (*p >= '0' && *p <= '9')
        !          1899:            {
        !          1900:              c = atoi (p);
        !          1901:              if (this_is_asm_operands && c >= (unsigned) insn_noperands)
        !          1902:                output_operand_lossage ("operand number out of range");
        !          1903:              else
        !          1904:                output_operand (operands[c], 0);
        !          1905:              while ((c = *p) >= '0' && c <= '9') p++;
        !          1906:            }
        !          1907:          /* % followed by punctuation: output something for that
        !          1908:             punctuation character alone, with no operand.
        !          1909:             The PRINT_OPERAND macro decides what is actually done.  */
        !          1910: #ifdef PRINT_OPERAND_PUNCT_VALID_P
        !          1911:          else if (PRINT_OPERAND_PUNCT_VALID_P (*p))
        !          1912:            output_operand (0, *p++);
        !          1913: #endif
        !          1914:          else
        !          1915:            output_operand_lossage ("invalid %%-code");
        !          1916:        }
        !          1917:     }
        !          1918: 
        !          1919:   if (flag_print_asm_name)
        !          1920:     {
        !          1921:       /* Annotate the assembly with a comment describing the pattern and
        !          1922:         alternative used.  */
        !          1923:       if (debug_insn)
        !          1924:        {
        !          1925:          register int num = INSN_CODE (debug_insn);
        !          1926:          fprintf (asm_out_file, " %s %d %s", 
        !          1927:                   ASM_COMMENT_START, INSN_UID (debug_insn), insn_name[num]);
        !          1928:          if (insn_n_alternatives[num] > 1)
        !          1929:            fprintf (asm_out_file, "/%d", which_alternative + 1);
        !          1930: 
        !          1931:          /* Clear this so only the first assembler insn
        !          1932:             of any rtl insn will get the special comment for -dp.  */
        !          1933:          debug_insn = 0;
        !          1934:        }
        !          1935:     }
        !          1936: 
        !          1937:   putc ('\n', asm_out_file);
        !          1938: }
        !          1939: 
        !          1940: /* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol.  */
        !          1941: 
        !          1942: void
        !          1943: output_asm_label (x)
        !          1944:      rtx x;
        !          1945: {
        !          1946:   char buf[256];
        !          1947: 
        !          1948:   if (GET_CODE (x) == LABEL_REF)
        !          1949:     ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (XEXP (x, 0)));
        !          1950:   else if (GET_CODE (x) == CODE_LABEL)
        !          1951:     ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
        !          1952:   else
        !          1953:     output_operand_lossage ("`%l' operand isn't a label");
        !          1954: 
        !          1955:   assemble_name (asm_out_file, buf);
        !          1956: }
        !          1957: 
        !          1958: /* Print operand X using machine-dependent assembler syntax.
        !          1959:    The macro PRINT_OPERAND is defined just to control this function.
        !          1960:    CODE is a non-digit that preceded the operand-number in the % spec,
        !          1961:    such as 'z' if the spec was `%z3'.  CODE is 0 if there was no char
        !          1962:    between the % and the digits.
        !          1963:    When CODE is a non-letter, X is 0.
        !          1964: 
        !          1965:    The meanings of the letters are machine-dependent and controlled
        !          1966:    by PRINT_OPERAND.  */
        !          1967: 
        !          1968: static void
        !          1969: output_operand (x, code)
        !          1970:      rtx x;
        !          1971:      int code;
        !          1972: {
        !          1973:   if (x && GET_CODE (x) == SUBREG)
        !          1974:     x = alter_subreg (x);
        !          1975:   PRINT_OPERAND (asm_out_file, x, code);
        !          1976: }
        !          1977: 
        !          1978: /* Print a memory reference operand for address X
        !          1979:    using machine-dependent assembler syntax.
        !          1980:    The macro PRINT_OPERAND_ADDRESS exists just to control this function.  */
        !          1981: 
        !          1982: void
        !          1983: output_address (x)
        !          1984:      rtx x;
        !          1985: {
        !          1986:   walk_alter_subreg (x);
        !          1987:   PRINT_OPERAND_ADDRESS (asm_out_file, x);
        !          1988: }
        !          1989: 
        !          1990: /* Print an integer constant expression in assembler syntax.
        !          1991:    Addition and subtraction are the only arithmetic
        !          1992:    that may appear in these expressions.  */
        !          1993: 
        !          1994: void
        !          1995: output_addr_const (file, x)
        !          1996:      FILE *file;
        !          1997:      rtx x;
        !          1998: {
        !          1999:   char buf[256];
        !          2000: 
        !          2001:  restart:
        !          2002:   switch (GET_CODE (x))
        !          2003:     {
        !          2004:     case PC:
        !          2005:       if (flag_pic)
        !          2006:        putc ('.', file);
        !          2007:       else
        !          2008:        abort ();
        !          2009:       break;
        !          2010: 
        !          2011:     case SYMBOL_REF:
        !          2012:       assemble_name (file, XSTR (x, 0));
        !          2013:       break;
        !          2014: 
        !          2015:     case LABEL_REF:
        !          2016:       ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (XEXP (x, 0)));
        !          2017:       assemble_name (asm_out_file, buf);
        !          2018:       break;
        !          2019: 
        !          2020:     case CODE_LABEL:
        !          2021:       ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
        !          2022:       assemble_name (asm_out_file, buf);
        !          2023:       break;
        !          2024: 
        !          2025:     case CONST_INT:
        !          2026:       fprintf (file, "%d", INTVAL (x));
        !          2027:       break;
        !          2028: 
        !          2029:     case CONST:
        !          2030:       /* This used to output parentheses around the expression,
        !          2031:         but that does not work on the 386 (either ATT or BSD assembler).  */
        !          2032:       output_addr_const (file, XEXP (x, 0));
        !          2033:       break;
        !          2034: 
        !          2035:     case CONST_DOUBLE:
        !          2036:       if (GET_MODE (x) == VOIDmode)
        !          2037:        {
        !          2038:          /* We can use %d if the number is <32 bits and positive.  */
        !          2039:          if (CONST_DOUBLE_HIGH (x) || CONST_DOUBLE_LOW (x) < 0)
        !          2040:            fprintf (file, "0x%x%08x",
        !          2041:                     CONST_DOUBLE_HIGH (x), CONST_DOUBLE_LOW (x));
        !          2042:          else
        !          2043:            fprintf (file, "%d", CONST_DOUBLE_LOW (x));
        !          2044:        }
        !          2045:       else
        !          2046:        /* We can't handle floating point constants;
        !          2047:           PRINT_OPERAND must handle them.  */
        !          2048:        output_operand_lossage ("floating constant misused");
        !          2049:       break;
        !          2050: 
        !          2051:     case PLUS:
        !          2052:       /* Some assemblers need integer constants to appear last (eg masm).  */
        !          2053:       if (GET_CODE (XEXP (x, 0)) == CONST_INT)
        !          2054:        {
        !          2055:          output_addr_const (file, XEXP (x, 1));
        !          2056:          if (INTVAL (XEXP (x, 0)) >= 0)
        !          2057:            fprintf (file, "+");
        !          2058:          output_addr_const (file, XEXP (x, 0));
        !          2059:        }
        !          2060:       else
        !          2061:        {
        !          2062:          output_addr_const (file, XEXP (x, 0));
        !          2063:          if (INTVAL (XEXP (x, 1)) >= 0)
        !          2064:            fprintf (file, "+");
        !          2065:          output_addr_const (file, XEXP (x, 1));
        !          2066:        }
        !          2067:       break;
        !          2068: 
        !          2069:     case MINUS:
        !          2070:       output_addr_const (file, XEXP (x, 0));
        !          2071:       fprintf (file, "-");
        !          2072:       output_addr_const (file, XEXP (x, 1));
        !          2073:       break;
        !          2074: 
        !          2075:     default:
        !          2076:       output_operand_lossage ("invalid expression as operand");
        !          2077:     }
        !          2078: }
        !          2079: 
        !          2080: /* A poor man's fprintf, with the added features of %I, %R, %L, and %U.
        !          2081:    %R prints the value of REGISTER_PREFIX.
        !          2082:    %L prints the value of LOCAL_LABEL_PREFIX.
        !          2083:    %U prints the value of USER_LABEL_PREFIX.
        !          2084:    %I prints the value of IMMEDIATE_PREFIX.
        !          2085:    Also supported are %d, %x, %s, %e, %f, %g and %%.  */
        !          2086: 
        !          2087: void
        !          2088: asm_fprintf (va_alist)
        !          2089:      va_dcl
        !          2090: {
        !          2091:   va_list argptr;
        !          2092:   FILE *file;
        !          2093:   char buf[10];
        !          2094:   char *p, *q, c;
        !          2095: 
        !          2096:   va_start (argptr);
        !          2097: 
        !          2098:   file = va_arg (argptr, FILE *);
        !          2099:   p = va_arg (argptr, char *);
        !          2100:   buf[0] = '%';
        !          2101: 
        !          2102:   while (c = *p++)
        !          2103:     switch (c)
        !          2104:       {
        !          2105:       case '%':
        !          2106:        c = *p++;
        !          2107:        q = &buf[1];
        !          2108:        while ((c >= '0' && c <= '9') || c == '.')
        !          2109:          {
        !          2110:            *q++ = c;
        !          2111:            c = *p++;
        !          2112:          }
        !          2113:        switch (c)
        !          2114:          {
        !          2115:          case '%':
        !          2116:            fprintf (file, "%%");
        !          2117:            break;
        !          2118: 
        !          2119:          case 'd':  case 'i':  case 'u':
        !          2120:          case 'x':  case 'p':  case 'X':
        !          2121:          case 'o':
        !          2122:            *q++ = c;
        !          2123:            *q = 0;
        !          2124:            fprintf (file, buf, va_arg (argptr, int));
        !          2125:            break;
        !          2126: 
        !          2127:          case 'e':
        !          2128:          case 'f':
        !          2129:          case 'g':
        !          2130:            *q++ = c;
        !          2131:            *q = 0;
        !          2132:            fprintf (file, buf, va_arg (argptr, double));
        !          2133:            break;
        !          2134: 
        !          2135:          case 's':
        !          2136:            *q++ = c;
        !          2137:            *q = 0;
        !          2138:            fprintf (file, buf, va_arg (argptr, char *));
        !          2139:            break;
        !          2140: 
        !          2141:          case 'R':
        !          2142: #ifdef REGISTER_PREFIX
        !          2143:            fprintf (file, "%s", REGISTER_PREFIX);
        !          2144: #endif
        !          2145:            break;
        !          2146: 
        !          2147:          case 'I':
        !          2148: #ifdef IMMEDIATE_PREFIX
        !          2149:            fprintf (file, "%s", IMMEDIATE_PREFIX);
        !          2150: #endif
        !          2151:            break;
        !          2152: 
        !          2153:          case 'L':
        !          2154: #ifdef LOCAL_LABEL_PREFIX
        !          2155:            fprintf (file, "%s", LOCAL_LABEL_PREFIX);
        !          2156: #endif
        !          2157:            break;
        !          2158: 
        !          2159:          case 'U':
        !          2160: #ifdef USER_LABEL_PREFIX
        !          2161:            fprintf (file, "%s", USER_LABEL_PREFIX);
        !          2162: #endif
        !          2163:            break;
        !          2164: 
        !          2165:          default:
        !          2166:            abort ();
        !          2167:          }
        !          2168:        break;
        !          2169: 
        !          2170:       default:
        !          2171:        fputc (c, file);
        !          2172:       }
        !          2173: }
        !          2174: 
        !          2175: /* Split up a CONST_DOUBLE or integer constant rtx
        !          2176:    into two rtx's for single words,
        !          2177:    storing in *FIRST the word that comes first in memory in the target
        !          2178:    and in *SECOND the other.  */
        !          2179: 
        !          2180: void
        !          2181: split_double (value, first, second)
        !          2182:      rtx value;
        !          2183:      rtx *first, *second;
        !          2184: {
        !          2185:   if (GET_CODE (value) == CONST_INT)
        !          2186:     {
        !          2187:       /* The rule for using CONST_INT for a wider mode
        !          2188:         is that we regard the value as signed.
        !          2189:         So sign-extend it.  */
        !          2190:       rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
        !          2191: #if WORDS_BIG_ENDIAN
        !          2192:       *first = high;
        !          2193:       *second = value;
        !          2194: #else
        !          2195:       *first = value;
        !          2196:       *second = high;
        !          2197: #endif
        !          2198:     }
        !          2199:   else if (GET_CODE (value) != CONST_DOUBLE)
        !          2200:     {
        !          2201: #if WORDS_BIG_ENDIAN
        !          2202:       *first = const0_rtx;
        !          2203:       *second = value;
        !          2204: #else
        !          2205:       *first = value;
        !          2206:       *second = const0_rtx;
        !          2207: #endif
        !          2208:     }
        !          2209:   else if (GET_MODE (value) == VOIDmode
        !          2210:           /* This is the old way we did CONST_DOUBLE integers.  */
        !          2211:           || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
        !          2212:     {
        !          2213:       /* In an integer, the words are defined as most and least significant.
        !          2214:         So order them by the target's convention.  */
        !          2215: #if WORDS_BIG_ENDIAN
        !          2216:       *first = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_HIGH (value));
        !          2217:       *second = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_LOW (value));
        !          2218: #else
        !          2219:       *first = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_LOW (value));
        !          2220:       *second = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_HIGH (value));
        !          2221: #endif
        !          2222:     }
        !          2223:   else
        !          2224:     {
        !          2225:       if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
        !          2226:           || HOST_BITS_PER_INT != BITS_PER_WORD)
        !          2227:          && ! flag_pretend_float)
        !          2228:       abort ();
        !          2229: 
        !          2230: #if defined (HOST_WORDS_BIG_ENDIAN) == WORDS_BIG_ENDIAN
        !          2231:       /* Host and target agree => no need to swap.  */
        !          2232:       *first = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_LOW (value));
        !          2233:       *second = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_HIGH (value));
        !          2234: #else
        !          2235:       *second = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_LOW (value));
        !          2236:       *first = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_HIGH (value));
        !          2237: #endif
        !          2238:     }
        !          2239: }
        !          2240: 
        !          2241: /* Return nonzero if this function has no function calls.  */
        !          2242: 
        !          2243: int
        !          2244: leaf_function_p ()
        !          2245: {
        !          2246:   rtx insn;
        !          2247: 
        !          2248:   if (profile_flag || profile_block_flag)
        !          2249:     return 0;
        !          2250: 
        !          2251:   for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
        !          2252:     {
        !          2253:       if (GET_CODE (insn) == CALL_INSN)
        !          2254:        return 0;
        !          2255:       if (GET_CODE (insn) == INSN
        !          2256:          && GET_CODE (PATTERN (insn)) == SEQUENCE
        !          2257:          && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN)
        !          2258:        return 0;
        !          2259:     }
        !          2260:   for (insn = current_function_epilogue_delay_list; insn; insn = XEXP (insn, 1))
        !          2261:     {
        !          2262:       if (GET_CODE (XEXP (insn, 0)) == CALL_INSN)
        !          2263:        return 0;
        !          2264:       if (GET_CODE (XEXP (insn, 0)) == INSN
        !          2265:          && GET_CODE (PATTERN (XEXP (insn, 0))) == SEQUENCE
        !          2266:          && GET_CODE (XVECEXP (PATTERN (XEXP (insn, 0)), 0, 0)) == CALL_INSN)
        !          2267:        return 0;
        !          2268:     }
        !          2269: 
        !          2270:   return 1;
        !          2271: }
        !          2272: 
        !          2273: /* On some machines, a function with no call insns
        !          2274:    can run faster if it doesn't create its own register window.
        !          2275:    When output, the leaf function should use only the "output"
        !          2276:    registers.  Ordinarily, the function would be compiled to use
        !          2277:    the "input" registers to find its arguments; it is a candidate
        !          2278:    for leaf treatment if it uses only the "input" registers.
        !          2279:    Leaf function treatment means renumbering so the function
        !          2280:    uses the "output" registers instead.  */
        !          2281: 
        !          2282: #ifdef LEAF_REGISTERS
        !          2283: 
        !          2284: static char permitted_reg_in_leaf_functions[] = LEAF_REGISTERS;
        !          2285: 
        !          2286: /* Return 1 if this function uses only the registers that can be
        !          2287:    safely renumbered.  */
        !          2288: 
        !          2289: int
        !          2290: only_leaf_regs_used ()
        !          2291: {
        !          2292:   int i;
        !          2293: 
        !          2294:   for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
        !          2295:     {
        !          2296:       if (regs_ever_live[i] > permitted_reg_in_leaf_functions[i])
        !          2297:        return 0;
        !          2298:     }
        !          2299:   return 1;
        !          2300: }
        !          2301: 
        !          2302: /* Scan all instructions and renumber all registers into those
        !          2303:    available in leaf functions.  */
        !          2304: 
        !          2305: static void
        !          2306: leaf_renumber_regs (first)
        !          2307:      rtx first;
        !          2308: {
        !          2309:   rtx insn;
        !          2310: 
        !          2311:   /* Renumber only the actual patterns.
        !          2312:      The reg-notes can contain frame pointer refs,
        !          2313:      and renumbering them could crash, and should not be needed.  */
        !          2314:   for (insn = first; insn; insn = NEXT_INSN (insn))
        !          2315:     if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
        !          2316:       leaf_renumber_regs_insn (PATTERN (insn));
        !          2317:   for (insn = current_function_epilogue_delay_list; insn; insn = XEXP (insn, 1))
        !          2318:     if (GET_RTX_CLASS (GET_CODE (XEXP (insn, 0))) == 'i')
        !          2319:       leaf_renumber_regs_insn (PATTERN (XEXP (insn, 0)));
        !          2320: }
        !          2321: 
        !          2322: /* Scan IN_RTX and its subexpressions, and renumber all regs into those
        !          2323:    available in leaf functions.  */
        !          2324: 
        !          2325: void
        !          2326: leaf_renumber_regs_insn (in_rtx)
        !          2327:      register rtx in_rtx;
        !          2328: {
        !          2329:   register int i, j;
        !          2330:   register char *format_ptr;
        !          2331: 
        !          2332:   if (in_rtx == 0)
        !          2333:     return;
        !          2334: 
        !          2335:   /* Renumber all input-registers into output-registers.
        !          2336:      renumbered_regs would be 1 for an output-register;
        !          2337:      they  */
        !          2338: 
        !          2339:   if (GET_CODE (in_rtx) == REG)
        !          2340:     {
        !          2341:       int newreg;
        !          2342: 
        !          2343:       /* Don't renumber the same reg twice.  */
        !          2344:       if (in_rtx->used)
        !          2345:        return;
        !          2346: 
        !          2347:       newreg = REGNO (in_rtx);
        !          2348:       /* Don't try to renumber pseudo regs.  It is possible for a psuedo reg
        !          2349:         to reach here as part of a REG_NOTE.  */
        !          2350:       if (newreg >= FIRST_PSEUDO_REGISTER)
        !          2351:        {
        !          2352:          in_rtx->used = 1;
        !          2353:          return;
        !          2354:        }
        !          2355:       newreg = LEAF_REG_REMAP (newreg);
        !          2356:       if (newreg < 0)
        !          2357:        abort ();
        !          2358:       regs_ever_live[REGNO (in_rtx)] = 0;
        !          2359:       regs_ever_live[newreg] = 1;
        !          2360:       REGNO (in_rtx) = newreg;
        !          2361:       in_rtx->used = 1;
        !          2362:     }
        !          2363: 
        !          2364:   if (GET_RTX_CLASS (GET_CODE (in_rtx)) == 'i')
        !          2365:     {
        !          2366:       /* Inside a SEQUENCE, we find insns.
        !          2367:         Renumber just the patterns of these insns,
        !          2368:         just as we do for the top-level insns.  */
        !          2369:       leaf_renumber_regs_insn (PATTERN (in_rtx));
        !          2370:       return;
        !          2371:     }
        !          2372: 
        !          2373:   format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
        !          2374: 
        !          2375:   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (in_rtx)); i++)
        !          2376:     switch (*format_ptr++)
        !          2377:       {
        !          2378:       case 'e':
        !          2379:        leaf_renumber_regs_insn (XEXP (in_rtx, i));
        !          2380:        break;
        !          2381: 
        !          2382:       case 'E':
        !          2383:        if (NULL != XVEC (in_rtx, i))
        !          2384:          {
        !          2385:            for (j = 0; j < XVECLEN (in_rtx, i); j++)
        !          2386:              leaf_renumber_regs_insn (XVECEXP (in_rtx, i, j));
        !          2387:          }
        !          2388:        break;
        !          2389: 
        !          2390:       case 'S':
        !          2391:       case 's':
        !          2392:       case '0':
        !          2393:       case 'i':
        !          2394:       case 'n':
        !          2395:       case 'u':
        !          2396:        break;
        !          2397: 
        !          2398:       default:
        !          2399:        abort ();
        !          2400:       }
        !          2401: }
        !          2402: #endif

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