asm_support_x86.S revision a0ff60587a7f81d8d065adf21008ead5f0251bbf 
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(__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, $1, and so on for macro arguments.
31    #define VAR(name,index) SYMBOL($index)
32    #define PLT_VAR(name, index) SYMBOL($index)
33    #define REG_VAR(name,index) %$index
34    #define CALL_MACRO(name,index) $index
35    #define FUNCTION_TYPE(name,index) .type $index, @function
36    #define SIZE(name,index) .size $index, .-$index
37
38    //  The use of $x for arguments mean that literals need to be represented with $$x in macros.
39    #define LITERAL(value) $value
40    #define MACRO_LITERAL(value) $$value
41#else
42    // Regular gas(1) lets you name macro parameters.
43    #define MACRO0(macro_name) .macro macro_name
44    #define MACRO1(macro_name, macro_arg1) .macro macro_name macro_arg1
45    #define MACRO2(macro_name, macro_arg1, macro_arg2) .macro macro_name macro_arg1, macro_arg2
46    #define MACRO3(macro_name, macro_arg1, macro_arg2, macro_arg3) .macro macro_name macro_arg1, macro_arg2, macro_arg3
47    #define END_MACRO .endm
48
49    // Regular gas(1) uses \argument_name for macro arguments.
50    // We need to turn on alternate macro syntax so we can use & instead or the preprocessor
51    // will screw us by inserting a space between the \ and the name. Even in this mode there's
52    // no special meaning to $, so literals are still just $x. The use of altmacro means % is a
53    // special character meaning care needs to be taken when passing registers as macro arguments.
54    .altmacro
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    #define FUNCTION_TYPE(name,index) .type name&, @function
60    #define SIZE(name,index) .size name, .-name
61
62    #define LITERAL(value) $value
63    #define MACRO_LITERAL(value) $value
64#endif
65
66    // CFI support.
67#if !defined(__APPLE__)
68    #define CFI_STARTPROC .cfi_startproc
69    #define CFI_ENDPROC .cfi_endproc
70    #define CFI_ADJUST_CFA_OFFSET(size) .cfi_adjust_cfa_offset size
71    #define CFI_DEF_CFA(reg,size) .cfi_def_cfa reg,size
72    #define CFI_DEF_CFA_REGISTER(reg) .cfi_def_cfa_register reg
73    #define CFI_RESTORE(reg) .cfi_restore reg
74    #define CFI_REL_OFFSET(reg,size) .cfi_rel_offset reg,size
75#else
76    // Mac OS' doesn't like cfi_* directives.
77    #define CFI_STARTPROC
78    #define CFI_ENDPROC
79    #define CFI_ADJUST_CFA_OFFSET(size)
80    #define CFI_DEF_CFA(reg,size)
81    #define CFI_DEF_CFA_REGISTER(reg)
82    #define CFI_RESTORE(reg)
83    #define CFI_REL_OFFSET(reg,size)
84#endif
85
86    // Symbols.
87#if !defined(__APPLE__)
88    #define SYMBOL(name) name
89    #if defined(__clang__) && (__clang_major__ < 4) && (__clang_minor__ < 5)
90        // TODO: Disabled for old clang 3.3, this leads to text reolocations and there should be a
91        // better fix.
92        #define PLT_SYMBOL(name) name // ## @PLT
93    #else
94        #define PLT_SYMBOL(name) name ## @PLT
95    #endif
96#else
97    // Mac OS' symbols have an _ prefix.
98    #define SYMBOL(name) _ ## name
99    #define PLT_SYMBOL(name) _ ## name
100#endif
101
102    /* Cache alignment for function entry */
103MACRO0(ALIGN_FUNCTION_ENTRY)
104    .balign 16
105END_MACRO
106
107MACRO1(DEFINE_FUNCTION, c_name)
108    FUNCTION_TYPE(\c_name, 0)
109    .globl VAR(c_name, 0)
110    ALIGN_FUNCTION_ENTRY
111VAR(c_name, 0):
112    CFI_STARTPROC
113    // Ensure we get a sane starting CFA.
114    CFI_DEF_CFA(esp, 4)
115END_MACRO
116
117MACRO1(END_FUNCTION, c_name)
118    CFI_ENDPROC
119    SIZE(\c_name, 0)
120END_MACRO
121
122MACRO1(PUSH, reg)
123    pushl REG_VAR(reg, 0)
124    CFI_ADJUST_CFA_OFFSET(4)
125    CFI_REL_OFFSET(REG_VAR(reg, 0), 0)
126END_MACRO
127
128MACRO1(POP, reg)
129    popl REG_VAR(reg,0)
130    CFI_ADJUST_CFA_OFFSET(-4)
131    CFI_RESTORE(REG_VAR(reg,0))
132END_MACRO
133
134MACRO1(UNIMPLEMENTED,name)
135    FUNCTION_TYPE(\name, 0)
136    .globl VAR(name, 0)
137    ALIGN_FUNCTION_ENTRY
138VAR(name, 0):
139    CFI_STARTPROC
140    int3
141    int3
142    CFI_ENDPROC
143    SIZE(\name, 0)
144END_MACRO
145
146MACRO0(SETUP_GOT_NOSAVE)
147    call __x86.get_pc_thunk.bx
148    addl $_GLOBAL_OFFSET_TABLE_, %ebx
149END_MACRO
150
151MACRO0(SETUP_GOT)
152    PUSH  ebx
153    SETUP_GOT_NOSAVE
154END_MACRO
155
156MACRO0(UNDO_SETUP_GOT)
157    POP  ebx
158END_MACRO
159
160#endif  // ART_RUNTIME_ARCH_X86_ASM_SUPPORT_X86_S_
161