| /* Target definitions for GNU compiler for Intel 80386 running System V.4 |
| Copyright (C) 1991 Free Software Foundation, Inc. |
| |
| Written by Ron Guilmette (rfg@netcom.com). |
| |
| 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 "i386/i386.h" /* Base i386 target machine definitions */ |
| #include "i386/att.h" /* Use the i386 AT&T assembler syntax */ |
| #include "svr4.h" /* Definitions common to all SVR4 targets */ |
| |
| #undef TARGET_VERSION |
| #define TARGET_VERSION fprintf (stderr, " (i386 System V Release 4)"); |
| |
| /* The svr4 ABI for the i386 says that records and unions are returned |
| in memory. */ |
| |
| #undef RETURN_IN_MEMORY |
| #define RETURN_IN_MEMORY(TYPE) \ |
| (TYPE_MODE (TYPE) == BLKmode) |
| |
| /* Define which macros to predefine. __svr4__ is our extension. */ |
| /* This used to define X86, but james@bigtex.cactus.org says that |
| is supposed to be defined optionally by user programs--not by default. */ |
| #define CPP_PREDEFINES \ |
| "-Di386 -Dunix -D__svr4__ -Asystem(unix) -Asystem(svr4) -Acpu(i386) -Amachine(i386)" |
| |
| /* This is how to output assembly code to define a `float' constant. |
| We always have to use a .long pseudo-op to do this because the native |
| SVR4 ELF assembler is buggy and it generates incorrect values when we |
| try to use the .float pseudo-op instead. */ |
| |
| #undef ASM_OUTPUT_FLOAT |
| #define ASM_OUTPUT_FLOAT(FILE,VALUE) \ |
| do { long value; \ |
| REAL_VALUE_TO_TARGET_SINGLE ((VALUE), value); \ |
| if (sizeof (int) == sizeof (long)) \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value); \ |
| else \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value); \ |
| } while (0) |
| |
| /* This is how to output assembly code to define a `double' constant. |
| We always have to use a pair of .long pseudo-ops to do this because |
| the native SVR4 ELF assembler is buggy and it generates incorrect |
| values when we try to use the the .double pseudo-op instead. */ |
| |
| #undef ASM_OUTPUT_DOUBLE |
| #define ASM_OUTPUT_DOUBLE(FILE,VALUE) \ |
| do { long value[2]; \ |
| REAL_VALUE_TO_TARGET_DOUBLE ((VALUE), value); \ |
| if (sizeof (int) == sizeof (long)) \ |
| { \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value[0]); \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value[1]); \ |
| } \ |
| else \ |
| { \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value[0]); \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value[1]); \ |
| } \ |
| } while (0) |
| |
| |
| #undef ASM_OUTPUT_LONG_DOUBLE |
| #define ASM_OUTPUT_LONG_DOUBLE(FILE,VALUE) \ |
| do { long value[3]; \ |
| REAL_VALUE_TO_TARGET_LONG_DOUBLE ((VALUE), value); \ |
| if (sizeof (int) == sizeof (long)) \ |
| { \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value[0]); \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value[1]); \ |
| fprintf((FILE), "%s\t0x%x\n", ASM_LONG, value[2]); \ |
| } \ |
| else \ |
| { \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value[0]); \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value[1]); \ |
| fprintf((FILE), "%s\t0x%lx\n", ASM_LONG, value[2]); \ |
| } \ |
| } while (0) |
| |
| /* Output at beginning of assembler file. */ |
| /* The .file command should always begin the output. */ |
| |
| #undef ASM_FILE_START |
| #define ASM_FILE_START(FILE) \ |
| do { \ |
| output_file_directive (FILE, main_input_filename); \ |
| fprintf (FILE, "\t.version\t\"01.01\"\n"); \ |
| } while (0) |
| |
| /* Define the register numbers to be used in Dwarf debugging information. |
| The SVR4 reference port C compiler uses the following register numbers |
| in its Dwarf output code: |
| |
| 0 for %eax (gnu regno = 0) |
| 1 for %ecx (gnu regno = 2) |
| 2 for %edx (gnu regno = 1) |
| 3 for %ebx (gnu regno = 3) |
| 4 for %esp (gnu regno = 7) |
| 5 for %ebp (gnu regno = 6) |
| 6 for %esi (gnu regno = 4) |
| 7 for %edi (gnu regno = 5) |
| |
| The following three DWARF register numbers are never generated by |
| the SVR4 C compiler or by the GNU compilers, but SDB on x86/svr4 |
| believes these numbers have these meanings. |
| |
| 8 for %eip (no gnu equivalent) |
| 9 for %eflags (no gnu equivalent) |
| 10 for %trapno (no gnu equivalent) |
| |
| It is not at all clear how we should number the FP stack registers |
| for the x86 architecture. If the version of SDB on x86/svr4 were |
| a bit less brain dead with respect to floating-point then we would |
| have a precedent to follow with respect to DWARF register numbers |
| for x86 FP registers, but the SDB on x86/svr4 is so completely |
| broken with respect to FP registers that it is hardly worth thinking |
| of it as something to strive for compatibility with. |
| |
| The version of x86/svr4 SDB I have at the moment does (partially) |
| seem to believe that DWARF register number 11 is associated with |
| the x86 register %st(0), but that's about all. Higher DWARF |
| register numbers don't seem to be associated with anything in |
| particular, and even for DWARF regno 11, SDB only seems to under- |
| stand that it should say that a variable lives in %st(0) (when |
| asked via an `=' command) if we said it was in DWARF regno 11, |
| but SDB still prints garbage when asked for the value of the |
| variable in question (via a `/' command). |
| |
| (Also note that the labels SDB prints for various FP stack regs |
| when doing an `x' command are all wrong.) |
| |
| Note that these problems generally don't affect the native SVR4 |
| C compiler because it doesn't allow the use of -O with -g and |
| because when it is *not* optimizing, it allocates a memory |
| location for each floating-point variable, and the memory |
| location is what gets described in the DWARF AT_location |
| attribute for the variable in question. |
| |
| Regardless of the severe mental illness of the x86/svr4 SDB, we |
| do something sensible here and we use the following DWARF |
| register numbers. Note that these are all stack-top-relative |
| numbers. |
| |
| 11 for %st(0) (gnu regno = 8) |
| 12 for %st(1) (gnu regno = 9) |
| 13 for %st(2) (gnu regno = 10) |
| 14 for %st(3) (gnu regno = 11) |
| 15 for %st(4) (gnu regno = 12) |
| 16 for %st(5) (gnu regno = 13) |
| 17 for %st(6) (gnu regno = 14) |
| 18 for %st(7) (gnu regno = 15) |
| */ |
| |
| #undef DBX_REGISTER_NUMBER |
| #define DBX_REGISTER_NUMBER(n) \ |
| ((n) == 0 ? 0 \ |
| : (n) == 1 ? 2 \ |
| : (n) == 2 ? 1 \ |
| : (n) == 3 ? 3 \ |
| : (n) == 4 ? 6 \ |
| : (n) == 5 ? 7 \ |
| : (n) == 6 ? 5 \ |
| : (n) == 7 ? 4 \ |
| : ((n) >= FIRST_STACK_REG && (n) <= LAST_STACK_REG) ? (n)+3 \ |
| : (-1)) |
| |
| /* The routine used to output sequences of byte values. We use a special |
| version of this for most svr4 targets because doing so makes the |
| generated assembly code more compact (and thus faster to assemble) |
| as well as more readable. Note that if we find subparts of the |
| character sequence which end with NUL (and which are shorter than |
| STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING. */ |
| |
| #undef ASM_OUTPUT_ASCII |
| #define ASM_OUTPUT_ASCII(FILE, STR, LENGTH) \ |
| do \ |
| { \ |
| register unsigned char *_ascii_bytes = (unsigned char *) (STR); \ |
| register unsigned char *limit = _ascii_bytes + (LENGTH); \ |
| register unsigned bytes_in_chunk = 0; \ |
| for (; _ascii_bytes < limit; _ascii_bytes++) \ |
| { \ |
| register unsigned char *p; \ |
| if (bytes_in_chunk >= 64) \ |
| { \ |
| fputc ('\n', (FILE)); \ |
| bytes_in_chunk = 0; \ |
| } \ |
| for (p = _ascii_bytes; p < limit && *p != '\0'; p++) \ |
| continue; \ |
| if (p < limit && (p - _ascii_bytes) <= STRING_LIMIT) \ |
| { \ |
| if (bytes_in_chunk > 0) \ |
| { \ |
| fputc ('\n', (FILE)); \ |
| bytes_in_chunk = 0; \ |
| } \ |
| ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes); \ |
| _ascii_bytes = p; \ |
| } \ |
| else \ |
| { \ |
| if (bytes_in_chunk == 0) \ |
| fprintf ((FILE), "\t.byte\t"); \ |
| else \ |
| fputc (',', (FILE)); \ |
| fprintf ((FILE), "0x%02x", *_ascii_bytes); \ |
| bytes_in_chunk += 5; \ |
| } \ |
| } \ |
| if (bytes_in_chunk > 0) \ |
| fprintf ((FILE), "\n"); \ |
| } \ |
| while (0) |
| |
| /* This is how to output an element of a case-vector that is relative. |
| This is only used for PIC code. See comments by the `casesi' insn in |
| i386.md for an explanation of the expression this outputs. */ |
| |
| #undef ASM_OUTPUT_ADDR_DIFF_ELT |
| #define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, VALUE, REL) \ |
| fprintf (FILE, "\t.long _GLOBAL_OFFSET_TABLE_+[.-%s%d]\n", LPREFIX, VALUE) |
| |
| /* Indicate that jump tables go in the text section. This is |
| necessary when compiling PIC code. */ |
| |
| #define JUMP_TABLES_IN_TEXT_SECTION |
| |
| /* A C statement (sans semicolon) to output to the stdio stream |
| FILE the assembler definition of uninitialized global DECL named |
| NAME whose size is SIZE bytes and alignment is ALIGN bytes. |
| Try to use asm_output_aligned_bss to implement this macro. */ |
| |
| #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \ |
| asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN) |
