1 /* Assembler macros for i386. 2 Copyright (C) 1991, 92, 93, 95, 96, 98 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, write to the Free 17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 18 02111-1307 USA. */ 19 20 #include_next <sysdep.h> 21 22 #ifdef __ASSEMBLER__ 23 24 /* Syntactic details of assembler. */ 25 26 #ifdef HAVE_ELF 27 28 /* ELF uses byte-counts for .align, most others use log2 of count of bytes. */ 29 #define ALIGNARG(log2) 1<<log2 30 /* For ELF we need the `.type' directive to make shared libs work right. */ 31 #define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg; 32 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name; 33 34 #else 35 36 #define ALIGNARG(log2) log2 37 #define ASM_TYPE_DIRECTIVE(name,type) /* Nothing is specified. */ 38 #define ASM_SIZE_DIRECTIVE(name) /* Nothing is specified. */ 39 40 #endif 41 42 43 /* Define an entry point visible from C. 44 45 There is currently a bug in gdb which prevents us from specifying 46 incomplete stabs information. Fake some entries here which specify 47 the current source file. */ 48 #define ENTRY(name) \ 49 STABS_CURRENT_FILE1("") \ 50 STABS_CURRENT_FILE(name) \ 51 ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \ 52 ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function) \ 53 .align ALIGNARG(4); \ 54 STABS_FUN(name) \ 55 C_LABEL(name) \ 56 CALL_MCOUNT 57 58 #undef END 59 #define END(name) \ 60 ASM_SIZE_DIRECTIVE(name) \ 61 STABS_FUN_END(name) 62 63 /* Remove the following two lines once the gdb bug is fixed. */ 64 #define STABS_CURRENT_FILE(name) \ 65 STABS_CURRENT_FILE1 (#name) 66 #define STABS_CURRENT_FILE1(name) \ 67 1: .stabs name,100,0,0,1b; 68 /* Emit stabs definition lines. We use F(0,1) and define t(0,1) as `int', 69 the same way gcc does it. */ 70 #define STABS_FUN(name) STABS_FUN2(name, name##:F(0,1)) 71 #define STABS_FUN2(name, namestr) \ 72 .stabs "int:t(0,1)=r(0,1);-2147483648;2147483647;",128,0,0,0; \ 73 .stabs #namestr,36,0,0,name; 74 #define STABS_FUN_END(name) \ 75 1: .stabs "",36,0,0,1b-name; 76 77 /* If compiled for profiling, call `mcount' at the start of each function. */ 78 #ifdef PROF 79 /* The mcount code relies on a normal frame pointer being on the stack 80 to locate our caller, so push one just for its benefit. */ 81 #define CALL_MCOUNT \ 82 pushl %ebp; movl %esp, %ebp; call JUMPTARGET(mcount); popl %ebp; 83 #else 84 #define CALL_MCOUNT /* Do nothing. */ 85 #endif 86 87 /* Since C identifiers are not normally prefixed with an underscore 88 on this system, the asm identifier `syscall_error' intrudes on the 89 C name space. Make sure we use an innocuous name. */ 90 #define syscall_error __syscall_error 91 #define mcount _mcount 92 93 #define PSEUDO(name, syscall_name, args) \ 94 lose: SYSCALL_PIC_SETUP \ 95 jmp JUMPTARGET(syscall_error) \ 96 .globl syscall_error; \ 97 ENTRY (name) \ 98 DO_CALL (syscall_name, args); \ 99 jb lose 100 101 #undef PSEUDO_END 102 #define PSEUDO_END(name) \ 103 END (name) 104 105 #ifdef PIC 106 #define JUMPTARGET(name) name##@PLT 107 #define SYSCALL_PIC_SETUP \ 108 pushl %ebx; \ 109 call 0f; \ 110 0: popl %ebx; \ 111 addl $_GLOBAL_OFFSET_TABLE+[.-0b], %ebx; 112 #else 113 #define JUMPTARGET(name) name 114 #define SYSCALL_PIC_SETUP /* Nothing. */ 115 #endif 116 117 /* Local label name for asm code. */ 118 #ifndef L 119 #define L(name) name 120 #endif 121 122 #endif /* __ASSEMBLER__ */ 123