1/* Assembler macros for x86-64.
2 Copyright (C) 2001-2016 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, see
17 <http://www.gnu.org/licenses/>. */
18
19#ifndef _X86_64_SYSDEP_H
20#define _X86_64_SYSDEP_H 1
21
22#include <sysdeps/generic/sysdep.h>
23
24#ifdef __ASSEMBLER__
25
26/* Syntactic details of assembler. */
27
28/* This macro is for setting proper CFI with DW_CFA_expression describing
29 the register as saved relative to %rsp instead of relative to the CFA.
30 Expression is DW_OP_drop, DW_OP_breg7 (%rsp is register 7), sleb128 offset
31 from %rsp. */
32#define cfi_offset_rel_rsp(regn, off) .cfi_escape 0x10, regn, 0x4, 0x13, \
33 0x77, off & 0x7F | 0x80, off >> 7
34
35/* ELF uses byte-counts for .align, most others use log2 of count of bytes. */
36#define ALIGNARG(log2) 1<<log2
37#define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
38
39
40/* Define an entry point visible from C. */
41#define ENTRY(name) \
42 .globl C_SYMBOL_NAME(name); \
43 .type C_SYMBOL_NAME(name),@function; \
44 .align ALIGNARG(4); \
45 C_LABEL(name) \
46 cfi_startproc; \
47 CALL_MCOUNT
48
49#undef END
50#define END(name) \
51 cfi_endproc; \
52 ASM_SIZE_DIRECTIVE(name)
53
54#define ENTRY_CHK(name) ENTRY (name)
55#define END_CHK(name) END (name)
56
57/* If compiled for profiling, call `mcount' at the start of each function. */
58#ifdef PROF
59/* The mcount code relies on a normal frame pointer being on the stack
60 to locate our caller, so push one just for its benefit. */
61#define CALL_MCOUNT \
62 pushq %rbp; \
63 cfi_adjust_cfa_offset(8); \
64 movq %rsp, %rbp; \
65 cfi_def_cfa_register(%rbp); \
66 call JUMPTARGET(mcount); \
67 popq %rbp; \
68 cfi_def_cfa(rsp,8);
69#else
70#define CALL_MCOUNT /* Do nothing. */
71#endif
72
73/* Since C identifiers are not normally prefixed with an underscore
74 on this system, the asm identifier `syscall_error' intrudes on the
75 C name space. Make sure we use an innocuous name. */
76#define syscall_error __syscall_error
77#define mcount _mcount
78
79#define PSEUDO(name, syscall_name, args) \
80lose: \
81 jmp JUMPTARGET(syscall_error) \
82 .globl syscall_error; \
83 ENTRY (name) \
84 DO_CALL (syscall_name, args); \
85 jb lose
86
87#undef PSEUDO_END
88#define PSEUDO_END(name) \
89 END (name)
90
91#undef JUMPTARGET
92#ifdef PIC
93#define JUMPTARGET(name) name##@PLT
94#else
95#define JUMPTARGET(name) name
96#endif
97
98/* Local label name for asm code. */
99#ifndef L
100/* ELF-like local names start with `.L'. */
101# define L(name) .L##name
102#endif
103
104#define atom_text_section .section ".text.atom", "ax"
105
106/* Long and pointer size in bytes. */
107#define LP_SIZE 8
108
109/* Instruction to operate on long and pointer. */
110#define LP_OP(insn) insn##q
111
112/* Assembler address directive. */
113#define ASM_ADDR .quad
114
115/* Registers to hold long and pointer. */
116#define RAX_LP rax
117#define RBP_LP rbp
118#define RBX_LP rbx
119#define RCX_LP rcx
120#define RDI_LP rdi
121#define RDX_LP rdx
122#define RSI_LP rsi
123#define RSP_LP rsp
124#define R8_LP r8
125#define R9_LP r9
126#define R10_LP r10
127#define R11_LP r11
128#define R12_LP r12
129#define R13_LP r13
130#define R14_LP r14
131#define R15_LP r15
132
133#else /* __ASSEMBLER__ */
134
135/* Long and pointer size in bytes. */
136#define LP_SIZE "8"
137
138/* Instruction to operate on long and pointer. */
139#define LP_OP(insn) #insn "q"
140
141/* Assembler address directive. */
142#define ASM_ADDR ".quad"
143
144/* Registers to hold long and pointer. */
145#define RAX_LP "rax"
146#define RBP_LP "rbp"
147#define RBX_LP "rbx"
148#define RCX_LP "rcx"
149#define RDI_LP "rdi"
150#define RDX_LP "rdx"
151#define RSI_LP "rsi"
152#define RSP_LP "rsp"
153#define R8_LP "r8"
154#define R9_LP "r9"
155#define R10_LP "r10"
156#define R11_LP "r11"
157#define R12_LP "r12"
158#define R13_LP "r13"
159#define R14_LP "r14"
160#define R15_LP "r15"
161
162#endif /* __ASSEMBLER__ */
163
164#endif /* _X86_64_SYSDEP_H */
165