asm_support_x86.S revision 235e77bd9f19e4faefda109be40f8744f3a66f40 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ART_RUNTIME_ARCH_X86_ASM_SUPPORT_X86_S_
18#define ART_RUNTIME_ARCH_X86_ASM_SUPPORT_X86_S_
19
20#include "asm_support_x86.h"
21
22#if defined(__APPLE__) || (defined(__clang__) && (__clang_major__ < 4) && (__clang_minor__ < 5))
23    // Clang's as(1) doesn't let you name macro parameters prior to 3.5.
24    #define MACRO0(macro_name) .macro macro_name
25    #define MACRO1(macro_name, macro_arg1) .macro macro_name
26    #define MACRO2(macro_name, macro_arg1, macro_args2) .macro macro_name
27    #define MACRO3(macro_name, macro_arg1, macro_args2, macro_args3) .macro macro_name
28    #define END_MACRO .endmacro
29
30    // Clang's as(1) uses $0, $1, and so on for macro arguments.
31    #define RAW_VAR(name,index) $index
32    #define VAR(name,index) SYMBOL($index)
33    #define PLT_VAR(name, index) SYMBOL($index)
34    #define REG_VAR(name,index) %$index
35    #define CALL_MACRO(name,index) $index
36
37    //  The use of $x for arguments mean that literals need to be represented with $$x in macros.
38    #define LITERAL(value) $value
39    #define MACRO_LITERAL(value) $$value
40#else
41    // Regular gas(1) lets you name macro parameters.
42    #define MACRO0(macro_name) .macro macro_name
43    #define MACRO1(macro_name, macro_arg1) .macro macro_name macro_arg1
44    #define MACRO2(macro_name, macro_arg1, macro_arg2) .macro macro_name macro_arg1, macro_arg2
45    #define MACRO3(macro_name, macro_arg1, macro_arg2, macro_arg3) .macro macro_name macro_arg1, macro_arg2, macro_arg3
46    #define END_MACRO .endm
47
48    // Regular gas(1) uses \argument_name for macro arguments.
49    // We need to turn on alternate macro syntax so we can use & instead or the preprocessor
50    // will screw us by inserting a space between the \ and the name. Even in this mode there's
51    // no special meaning to $, so literals are still just $x. The use of altmacro means % is a
52    // special character meaning care needs to be taken when passing registers as macro arguments.
53    .altmacro
54    #define RAW_VAR(name,index) name&
55    #define VAR(name,index) name&
56    #define PLT_VAR(name, index) name&@PLT
57    #define REG_VAR(name,index) %name
58    #define CALL_MACRO(name,index) name&
59
60    #define LITERAL(value) $value
61    #define MACRO_LITERAL(value) $value
62#endif
63
64#if defined(__APPLE__)
65    #define FUNCTION_TYPE(name,index)
66    #define SIZE(name,index)
67#elif defined(__clang__) && (__clang_major__ < 4) && (__clang_minor__ < 5)
68    #define FUNCTION_TYPE(name,index) .type $index, @function
69    #define SIZE(name,index) .size $index, .-$index
70#else
71    #define FUNCTION_TYPE(name,index) .type name&, @function
72    #define SIZE(name,index) .size name, .-name
73#endif
74
75    // CFI support.
76#if !defined(__APPLE__)
77    #define CFI_STARTPROC .cfi_startproc
78    #define CFI_ENDPROC .cfi_endproc
79    #define CFI_ADJUST_CFA_OFFSET(size) .cfi_adjust_cfa_offset size
80    #define CFI_DEF_CFA(reg,size) .cfi_def_cfa reg,size
81    #define CFI_DEF_CFA_REGISTER(reg) .cfi_def_cfa_register reg
82    #define CFI_RESTORE(reg) .cfi_restore reg
83    #define CFI_REL_OFFSET(reg,size) .cfi_rel_offset reg,size
84    #define CFI_RESTORE_STATE .cfi_restore_state
85    #define CFI_REMEMBER_STATE .cfi_remember_state
86#else
87    // Mac OS' doesn't like cfi_* directives.
88    #define CFI_STARTPROC
89    #define CFI_ENDPROC
90    #define CFI_ADJUST_CFA_OFFSET(size)
91    #define CFI_DEF_CFA(reg,size)
92    #define CFI_DEF_CFA_REGISTER(reg)
93    #define CFI_RESTORE(reg)
94    #define CFI_REL_OFFSET(reg,size)
95    #define CFI_RESTORE_STATE
96    #define CFI_REMEMBER_STATE
97#endif
98
99    // Symbols.
100#if !defined(__APPLE__)
101    #define SYMBOL(name) name
102    #if defined(__clang__) && (__clang_major__ < 4) && (__clang_minor__ < 5)
103        // TODO: Disabled for old clang 3.3, this leads to text relocations and there should be a
104        // better fix.
105        #define PLT_SYMBOL(name) name // ## @PLT
106    #else
107        #define PLT_SYMBOL(name) name ## @PLT
108    #endif
109#else
110    // Mac OS' symbols have an _ prefix.
111    #define SYMBOL(name) _ ## name
112    #define PLT_SYMBOL(name) _ ## name
113#endif
114
115// Directive to hide a function symbol.
116#if defined(__APPLE__)
117    #define ASM_HIDDEN .private_extern
118#else
119    #define ASM_HIDDEN .hidden
120#endif
121
122    /* Cache alignment for function entry */
123MACRO0(ALIGN_FUNCTION_ENTRY)
124    .balign 16
125END_MACRO
126
127MACRO1(DEFINE_FUNCTION, c_name)
128    FUNCTION_TYPE(\c_name, 0)
129    ASM_HIDDEN VAR(c_name, 0)
130    .globl VAR(c_name, 0)
131    ALIGN_FUNCTION_ENTRY
132VAR(c_name, 0):
133    CFI_STARTPROC
134    // Ensure we get a sane starting CFA.
135    CFI_DEF_CFA(esp, 4)
136END_MACRO
137
138MACRO1(DEFINE_FUNCTION_NO_HIDE, c_name)
139    FUNCTION_TYPE(\c_name, 0)
140    .globl VAR(c_name, 0)
141    ALIGN_FUNCTION_ENTRY
142VAR(c_name, 0):
143    CFI_STARTPROC
144    // Ensure we get a sane starting CFA.
145    CFI_DEF_CFA(esp, 4)
146END_MACRO
147
148MACRO1(END_FUNCTION, c_name)
149    CFI_ENDPROC
150    SIZE(\c_name, 0)
151END_MACRO
152
153MACRO1(PUSH, reg)
154    pushl REG_VAR(reg, 0)
155    CFI_ADJUST_CFA_OFFSET(4)
156    CFI_REL_OFFSET(REG_VAR(reg, 0), 0)
157END_MACRO
158
159MACRO1(POP, reg)
160    popl REG_VAR(reg,0)
161    CFI_ADJUST_CFA_OFFSET(-4)
162    CFI_RESTORE(REG_VAR(reg,0))
163END_MACRO
164
165MACRO1(UNIMPLEMENTED,name)
166    FUNCTION_TYPE(\name, 0)
167    .globl VAR(name, 0)
168    ALIGN_FUNCTION_ENTRY
169VAR(name, 0):
170    CFI_STARTPROC
171    int3
172    int3
173    CFI_ENDPROC
174    SIZE(\name, 0)
175END_MACRO
176
177MACRO0(SETUP_GOT_NOSAVE)
178#ifndef __APPLE__
179    call __x86.get_pc_thunk.bx
180    addl $_GLOBAL_OFFSET_TABLE_, %ebx
181#endif
182END_MACRO
183
184MACRO0(SETUP_GOT)
185    PUSH  ebx
186    SETUP_GOT_NOSAVE
187END_MACRO
188
189MACRO0(UNDO_SETUP_GOT)
190    POP  ebx
191END_MACRO
192
193#endif  // ART_RUNTIME_ARCH_X86_ASM_SUPPORT_X86_S_
194