i370.c

linux下的gcc编译器

/* Subroutines for insn-output.c for System/370.
   Copyright (C) 1989, 1993, 1995, 1997, 1998, 1999, 2000, 2002
   Free Software Foundation, Inc.
   Contributed by Jan Stein ([e-mail]).
   Modified for OS/390 LanguageEnvironment C by Dave Pitts ([e-mail])
   Hacked for Linux-ELF/390 by Linas Vepstas ([e-mail]) 

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "config.h"
#include "system.h"
#include "rtl.h"
#include "tree.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "real.h"
#include "insn-config.h"
#include "conditions.h"
#include "output.h"
#include "insn-attr.h"
#include "function.h"
#include "expr.h"
#include "flags.h"
#include "recog.h"
#include "toplev.h"
#include "cpplib.h"
#include "tm_p.h"
#include "target.h"
#include "target-def.h"

extern FILE *asm_out_file;

/* Label node.  This structure is used to keep track of labels 
      on the various pages in the current routine.
   The label_id is the numeric ID of the label,
   The label_page is the page on which it actually appears,
   The first_ref_page is the page on which the true first ref appears.
   The label_addr is an estimate of its location in the current routine,
   The label_first & last_ref are estimates of where the earliest and
      latest references to this label occur.  */

typedef struct label_node
  {
    struct label_node *label_next;
    int label_id;
    int label_page;
    int first_ref_page;

    int label_addr;
    int label_first_ref;
    int label_last_ref;
  }
label_node_t;

/* Is 1 when a label has been generated and the base register must be reloaded.  */
int mvs_need_base_reload = 0;

/* Current function starting base page.  */
int function_base_page;

/* Length of the current page code.  */
int mvs_page_code;

/* Length of the current page literals.  */
int mvs_page_lit;

/* Current function name.  */
char *mvs_function_name = 0;

/* Current function name length.  */
int mvs_function_name_length = 0;

/* Page number for multi-page functions.  */
int mvs_page_num = 0;

/* Label node list anchor.  */
static label_node_t *label_anchor = 0;

/* Label node free list anchor.  */
static label_node_t *free_anchor = 0;

/* Assembler source file descriptor.  */
static FILE *assembler_source = 0;

static label_node_t * mvs_get_label PARAMS ((int));
static void i370_label_scan PARAMS ((void));
#ifdef TARGET_HLASM
static bool i370_hlasm_assemble_integer PARAMS ((rtx, unsigned int, int));
static void i370_globalize_label PARAMS ((FILE *, const char *));
#endif
static void i370_output_function_prologue PARAMS ((FILE *, HOST_WIDE_INT));
static void i370_output_function_epilogue PARAMS ((FILE *, HOST_WIDE_INT));
#ifdef LONGEXTERNAL
static int mvs_hash_alias PARAMS ((const char *));
#endif
static void i370_encode_section_info PARAMS ((tree, int));

/* ===================================================== */
/* defines and functions specific to the HLASM assembler */
#ifdef TARGET_HLASM

#define MVS_HASH_PRIME 999983
#if defined(HOST_EBCDIC)
#define MVS_SET_SIZE 256
#else
#define MVS_SET_SIZE 128
#endif

#ifndef MAX_MVS_LABEL_SIZE
#define MAX_MVS_LABEL_SIZE 8
#endif

#define MAX_LONG_LABEL_SIZE 255

/* Alias node, this structure is used to keep track of aliases to external
   variables. The IBM assembler allows an alias to an external name 
   that is longer that 8 characters; but only once per assembly.
   Also, this structure stores the #pragma map info.  */
typedef struct alias_node
  {
    struct alias_node *alias_next;
    int  alias_emitted;
    char alias_name [MAX_MVS_LABEL_SIZE + 1];
    char real_name [MAX_LONG_LABEL_SIZE + 1];
  }
alias_node_t;

/* Alias node list anchor.  */
static alias_node_t *alias_anchor = 0;

/* Define the length of the internal MVS function table.  */
#define MVS_FUNCTION_TABLE_LENGTH 32

/* C/370 internal function table.  These functions use non-standard linkage
   and must handled in a special manner.  */
static const char *const mvs_function_table[MVS_FUNCTION_TABLE_LENGTH] =
{
#if defined(HOST_EBCDIC) /* Changed for EBCDIC collating sequence */
   "ceil",     "edc_acos", "edc_asin", "edc_atan", "edc_ata2", "edc_cos",
   "edc_cosh", "edc_erf",  "edc_erfc", "edc_exp",  "edc_gamm", "edc_lg10",
   "edc_log",  "edc_sin",  "edc_sinh", "edc_sqrt", "edc_tan",  "edc_tanh",
   "fabs",     "floor",    "fmod",     "frexp",    "hypot",    "jn",
   "j0",       "j1",       "ldexp",    "modf",     "pow",      "yn",
   "y0",       "y1"
#else
   "ceil",     "edc_acos", "edc_asin", "edc_ata2", "edc_atan", "edc_cos",
   "edc_cosh", "edc_erf",  "edc_erfc", "edc_exp",  "edc_gamm", "edc_lg10",
   "edc_log",  "edc_sin",  "edc_sinh", "edc_sqrt", "edc_tan",  "edc_tanh",
   "fabs",     "floor",    "fmod",     "frexp",    "hypot",    "j0",
   "j1",       "jn",       "ldexp",    "modf",     "pow",      "y0",
   "y1",       "yn"
#endif
};

#endif /* TARGET_HLASM */
/* ===================================================== */

/* ASCII to EBCDIC conversion table.  */
static const unsigned char ascebc[256] =
{
 /*00  NL    SH    SX    EX    ET    NQ    AK    BL */
     0x00, 0x01, 0x02, 0x03, 0x37, 0x2D, 0x2E, 0x2F,
 /*08  BS    HT    LF    VT    FF    CR    SO    SI */
     0x16, 0x05, 0x15, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
 /*10  DL    D1    D2    D3    D4    NK    SN    EB */
     0x10, 0x11, 0x12, 0x13, 0x3C, 0x3D, 0x32, 0x26,
 /*18  CN    EM    SB    EC    FS    GS    RS    US */
     0x18, 0x19, 0x3F, 0x27, 0x1C, 0x1D, 0x1E, 0x1F,
 /*20  SP     !     "     #     $     %     &     ' */
     0x40, 0x5A, 0x7F, 0x7B, 0x5B, 0x6C, 0x50, 0x7D,
 /*28   (     )     *     +     ,     -    .      / */
     0x4D, 0x5D, 0x5C, 0x4E, 0x6B, 0x60, 0x4B, 0x61,
 /*30   0     1     2     3     4     5     6     7 */
     0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
 /*38   8     9     :     ;     <     =     >     ? */
     0xF8, 0xF9, 0x7A, 0x5E, 0x4C, 0x7E, 0x6E, 0x6F,
 /*40   @     A     B     C     D     E     F     G */
     0x7C, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7,
 /*48   H     I     J     K     L     M     N     O */
     0xC8, 0xC9, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
 /*50   P     Q     R     S     T     U     V     W */
     0xD7, 0xD8, 0xD9, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6,
 /*58   X     Y     Z     [     \     ]     ^     _ */
     0xE7, 0xE8, 0xE9, 0xAD, 0xE0, 0xBD, 0x5F, 0x6D,
 /*60   `     a     b     c     d     e     f     g */
     0x79, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
 /*68   h     i     j     k     l     m     n     o */
     0x88, 0x89, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96,
 /*70   p     q     r     s     t     u     v     w */
     0x97, 0x98, 0x99, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6,
 /*78   x     y     z     {     |     }     ~    DL */
     0xA7, 0xA8, 0xA9, 0xC0, 0x4F, 0xD0, 0xA1, 0x07,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
     0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0xFF
};

/* EBCDIC to ASCII conversion table.  */
static const unsigned char ebcasc[256] =
{
 /*00  NU    SH    SX    EX    PF    HT    LC    DL */
     0x00, 0x01, 0x02, 0x03, 0x00, 0x09, 0x00, 0x7F,
 /*08              SM    VT    FF    CR    SO    SI */
     0x00, 0x00, 0x00, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
 /*10  DE    D1    D2    TM    RS    NL    BS    IL */
     0x10, 0x11, 0x12, 0x13, 0x14, 0x0A, 0x08, 0x00,
 /*18  CN    EM    CC    C1    FS    GS    RS    US */
     0x18, 0x19, 0x00, 0x00, 0x1C, 0x1D, 0x1E, 0x1F,
 /*20  DS    SS    FS          BP    LF    EB    EC */
     0x00, 0x00, 0x00, 0x00, 0x00, 0x0A, 0x17, 0x1B,
 /*28              SM    C2    EQ    AK    BL       */
     0x00, 0x00, 0x00, 0x00, 0x05, 0x06, 0x07, 0x00,
 /*30              SY          PN    RS    UC    ET */
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
 /*38                    C3    D4    NK          SU */
     0x00, 0x00, 0x00, 0x00, 0x14, 0x15, 0x00, 0x1A,
 /*40  SP                                           */
     0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*48                     .     <     (     +     | */
     0x00, 0x00, 0x00, 0x2E, 0x3C, 0x28, 0x2B, 0x7C,
 /*50   &                                           */
     0x26, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*58               !     $     *     )     ;     ^ */
     0x00, 0x00, 0x21, 0x24, 0x2A, 0x29, 0x3B, 0x5E,
 /*60   -     /                                     */
     0x2D, 0x2F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*68                     ,     %     _     >     ? */
     0x00, 0x00, 0x00, 0x2C, 0x25, 0x5F, 0x3E, 0x3F,
 /*70                                               */
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*78         `     :     #     @     '     =     " */
     0x00, 0x60, 0x3A, 0x23, 0x40, 0x27, 0x3D, 0x22,
 /*80         a     b     c     d     e     f     g */
     0x00, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
 /*88   h     i           {                         */
     0x68, 0x69, 0x00, 0x7B, 0x00, 0x00, 0x00, 0x00,
 /*90         j     k     l     m     n     o     p */
     0x00, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70,
 /*98   q     r           }                         */
     0x71, 0x72, 0x00, 0x7D, 0x00, 0x00, 0x00, 0x00,
 /*A0         ~     s     t     u     v     w     x */
     0x00, 0x7E, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
 /*A8   y     z                       [             */
     0x79, 0x7A, 0x00, 0x00, 0x00, 0x5B, 0x00, 0x00,
 /*B0                                               */
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*B8                                 ]             */
     0x00, 0x00, 0x00, 0x00, 0x00, 0x5D, 0x00, 0x00,
 /*C0   {     A     B     C     D     E     F     G */
     0x7B, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
 /*C8   H     I                                     */
     0x48, 0x49, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*D0   }     J     K     L     M     N     O     P */
     0x7D, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50,
 /*D8   Q     R                                     */
     0x51, 0x52, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*E0   \           S     T     U     V     W     X */
     0x5C, 0x00, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
 /*E8   Y     Z                                     */
     0x59, 0x5A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*F0   0     1     2     3     4     5     6     7 */
     0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
 /*F8   8     9                                     */
     0x38, 0x39, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF
};

/* Initialize the GCC target structure.  */
#ifdef TARGET_HLASM
#undef TARGET_ASM_BYTE_OP
#define TARGET_ASM_BYTE_OP NULL
#undef TARGET_ASM_ALIGNED_HI_OP
#define TARGET_ASM_ALIGNED_HI_OP NULL
#undef TARGET_ASM_ALIGNED_SI_OP
#define TARGET_ASM_ALIGNED_SI_OP NULL
#undef TARGET_ASM_INTEGER
#define TARGET_ASM_INTEGER i370_hlasm_assemble_integer
#undef TARGET_ASM_GLOBALIZE_LABEL
#define TARGET_ASM_GLOBALIZE_LABEL i370_globalize_label
#endif

#undef TARGET_ASM_FUNCTION_PROLOGUE
#define TARGET_ASM_FUNCTION_PROLOGUE i370_output_function_prologue
#undef TARGET_ASM_FUNCTION_EPILOGUE
#define TARGET_ASM_FUNCTION_EPILOGUE i370_output_function_epilogue
#undef TARGET_ENCODE_SECTION_INFO
#define TARGET_ENCODE_SECTION_INFO i370_encode_section_info

struct gcc_target targetm = TARGET_INITIALIZER;

/* Set global variables as needed for the options enabled.  */

void
override_options ()
{
  /* We're 370 floating point, not IEEE floating point.  */
  memset (real_format_for_mode, 0, sizeof real_format_for_mode);
  real_format_for_mode[SFmode - QFmode] = &i370_single_format;
  real_format_for_mode[DFmode - QFmode] = &i370_double_format;
}


/* Map characters from one character set to another.
   C is the character to be translated.  */

char
mvs_map_char (c)
     int c;
{
#if defined(TARGET_EBCDIC) && !defined(HOST_EBCDIC)
  fprintf (stderr, "mvs_map_char: TE & !HE: c = %02x\n", c);
  return ascebc[c];
#else
#if defined(HOST_EBCDIC) && !defined(TARGET_EBCDIC)
  fprintf (stderr, "mvs_map_char: !TE & HE: c = %02x\n", c);
  return ebcasc[c];
#else
  fprintf (stderr, "mvs_map_char: !TE & !HE: c = %02x\n", c);
  return c;
#endif
#endif
}

/* ===================================================== */
/* The following three routines are used to determine whther 
   forward branch is on this page, or is a far jump.  We use
   the "length" attr on an insn [(set_atter "length" "4")]
   to store the largest possible code length that insn
   could have.  This gives us a hint of the address of a
   branch destination, and from that, we can work out 
   the length of the jump, and whether its on page or not. 
 */

/* Return the destination address of a branch.  */

int
i370_branch_dest (branch)
     rtx branch;
{
  rtx dest = SET_SRC (PATTERN (branch));
  int dest_uid;
  int dest_addr;

  /* first, compute the estimated address of the branch target */
  if (GET_CODE (dest) == IF_THEN_ELSE)
    dest = XEXP (dest, 1);
  dest = XEXP (dest, 0);
  dest_uid = INSN_UID (dest);
  dest_addr = INSN_ADDRESSES (dest_uid);

  /* next, record the address of this insn as the true addr of first ref */
  {
     label_node_t *lp;
     rtx label = JUMP_LABEL (branch);
     int labelno = CODE_LABEL_NUMBER (label);

     if (!label || CODE_LABEL != GET_CODE (label)) abort ();

     lp = mvs_get_label (labelno);
     if (-1 == lp -> first_ref_page) lp->first_ref_page = mvs_page_num;
  }
  return dest_addr;
}

int
i370_branch_length (insn)
     rtx insn;
{
  int here, there;
  here = INSN_ADDRESSES (INSN_UID (insn));
  there = i370_branch_dest (insn);
  return (there - here);
}