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asm.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVUTIL_X86_ASM_H
22 #define AVUTIL_X86_ASM_H
23 
24 #include <stdint.h>
25 #include "config.h"
26 
27 typedef struct xmm_reg { uint64_t a, b; } xmm_reg;
28 typedef struct ymm_reg { uint64_t a, b, c, d; } ymm_reg;
29 
30 #if ARCH_X86_64
31 # define OPSIZE "q"
32 # define REG_a "rax"
33 # define REG_b "rbx"
34 # define REG_c "rcx"
35 # define REG_d "rdx"
36 # define REG_D "rdi"
37 # define REG_S "rsi"
38 # define PTR_SIZE "8"
39 typedef int64_t x86_reg;
40 
41 /* REG_SP is defined in Solaris sys headers, so use REG_sp */
42 # define REG_sp "rsp"
43 # define REG_BP "rbp"
44 # define REGBP rbp
45 # define REGa rax
46 # define REGb rbx
47 # define REGc rcx
48 # define REGd rdx
49 # define REGSP rsp
50 
51 #elif ARCH_X86_32
52 
53 # define OPSIZE "l"
54 # define REG_a "eax"
55 # define REG_b "ebx"
56 # define REG_c "ecx"
57 # define REG_d "edx"
58 # define REG_D "edi"
59 # define REG_S "esi"
60 # define PTR_SIZE "4"
61 typedef int32_t x86_reg;
62 
63 # define REG_sp "esp"
64 # define REG_BP "ebp"
65 # define REGBP ebp
66 # define REGa eax
67 # define REGb ebx
68 # define REGc ecx
69 # define REGd edx
70 # define REGSP esp
71 #else
72 typedef int x86_reg;
73 #endif
74 
75 #define HAVE_7REGS (ARCH_X86_64 || (HAVE_EBX_AVAILABLE && HAVE_EBP_AVAILABLE))
76 #define HAVE_6REGS (ARCH_X86_64 || (HAVE_EBX_AVAILABLE || HAVE_EBP_AVAILABLE))
77 
78 #if ARCH_X86_64 && defined(PIC)
79 # define BROKEN_RELOCATIONS 1
80 #endif
81 
82 /*
83  * If gcc is not set to support sse (-msse) it will not accept xmm registers
84  * in the clobber list for inline asm. XMM_CLOBBERS takes a list of xmm
85  * registers to be marked as clobbered and evaluates to nothing if they are
86  * not supported, or to the list itself if they are supported. Since a clobber
87  * list may not be empty, XMM_CLOBBERS_ONLY should be used if the xmm
88  * registers are the only in the clobber list.
89  * For example a list with "eax" and "xmm0" as clobbers should become:
90  * : XMM_CLOBBERS("xmm0",) "eax"
91  * and a list with only "xmm0" should become:
92  * XMM_CLOBBERS_ONLY("xmm0")
93  */
94 #if HAVE_XMM_CLOBBERS
95 # define XMM_CLOBBERS(...) __VA_ARGS__
96 # define XMM_CLOBBERS_ONLY(...) : __VA_ARGS__
97 #else
98 # define XMM_CLOBBERS(...)
99 # define XMM_CLOBBERS_ONLY(...)
100 #endif
101 
102 /* Use to export labels from asm. */
103 #define LABEL_MANGLE(a) EXTERN_PREFIX #a
104 
105 // Use rip-relative addressing if compiling PIC code on x86-64.
106 #if ARCH_X86_64 && defined(PIC)
107 # define LOCAL_MANGLE(a) #a "(%%rip)"
108 #else
109 # define LOCAL_MANGLE(a) #a
110 #endif
111 
112 #if HAVE_INLINE_ASM_DIRECT_SYMBOL_REFS
113 # define MANGLE(a) EXTERN_PREFIX LOCAL_MANGLE(a)
114 # define NAMED_CONSTRAINTS_ADD(...)
115 # define NAMED_CONSTRAINTS(...)
116 # define NAMED_CONSTRAINTS_ARRAY_ADD(...)
117 # define NAMED_CONSTRAINTS_ARRAY(...)
118 #else
119  /* When direct symbol references are used in code passed to a compiler that does not support them
120  * then these references need to be converted to named asm constraints instead.
121  * Instead of returning a direct symbol MANGLE now returns a named constraint for that specific symbol.
122  * In order for this to work there must also be a corresponding entry in the asm-interface. To add this
123  * entry use the macro NAMED_CONSTRAINTS() and pass in a list of each symbol reference used in the
124  * corresponding block of code. (e.g. NAMED_CONSTRAINTS(var1,var2,var3) where var1 is the first symbol etc. ).
125  * If there are already existing constraints then use NAMED_CONSTRAINTS_ADD to add to the existing constraint list.
126  */
127 # define MANGLE(a) "%["#a"]"
128  // Intel/MSVC does not correctly expand va-args so we need a rather ugly hack in order to get it to work
129 # define FE_0(P,X) P(X)
130 # define FE_1(P,X,X1) P(X), FE_0(P,X1)
131 # define FE_2(P,X,X1,X2) P(X), FE_1(P,X1,X2)
132 # define FE_3(P,X,X1,X2,X3) P(X), FE_2(P,X1,X2,X3)
133 # define FE_4(P,X,X1,X2,X3,X4) P(X), FE_3(P,X1,X2,X3,X4)
134 # define FE_5(P,X,X1,X2,X3,X4,X5) P(X), FE_4(P,X1,X2,X3,X4,X5)
135 # define FE_6(P,X,X1,X2,X3,X4,X5,X6) P(X), FE_5(P,X1,X2,X3,X4,X5,X6)
136 # define FE_7(P,X,X1,X2,X3,X4,X5,X6,X7) P(X), FE_6(P,X1,X2,X3,X4,X5,X6,X7)
137 # define FE_8(P,X,X1,X2,X3,X4,X5,X6,X7,X8) P(X), FE_7(P,X1,X2,X3,X4,X5,X6,X7,X8)
138 # define FE_9(P,X,X1,X2,X3,X4,X5,X6,X7,X8,X9) P(X), FE_8(P,X1,X2,X3,X4,X5,X6,X7,X8,X9)
139 # define GET_FE_IMPL(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,NAME,...) NAME
140 # define GET_FE(A) GET_FE_IMPL A
141 # define GET_FE_GLUE(x, y) x y
142 # define FOR_EACH_VA(P,...) GET_FE_GLUE(GET_FE((__VA_ARGS__,FE_9,FE_8,FE_7,FE_6,FE_5,FE_4,FE_3,FE_2,FE_1,FE_0)), (P,__VA_ARGS__))
143 # define NAME_CONSTRAINT(x) [x] "m"(x)
144  // Parameters are a list of each symbol reference required
145 # define NAMED_CONSTRAINTS_ADD(...) , FOR_EACH_VA(NAME_CONSTRAINT,__VA_ARGS__)
146  // Same but without comma for when there are no previously defined constraints
147 # define NAMED_CONSTRAINTS(...) FOR_EACH_VA(NAME_CONSTRAINT,__VA_ARGS__)
148  // Same as above NAMED_CONSTRAINTS except used for passing arrays/pointers instead of normal variables
149 # define NAME_CONSTRAINT_ARRAY(x) [x] "m"(*x)
150 # define NAMED_CONSTRAINTS_ARRAY_ADD(...) , FOR_EACH_VA(NAME_CONSTRAINT_ARRAY,__VA_ARGS__)
151 # define NAMED_CONSTRAINTS_ARRAY(...) FOR_EACH_VA(NAME_CONSTRAINT_ARRAY,__VA_ARGS__)
152 #endif
153 
154 #endif /* AVUTIL_X86_ASM_H */
uint64_t b
Definition: asm.h:27
uint64_t d
Definition: asm.h:28
Definition: asm.h:27
uint64_t a
Definition: asm.h:28
uint64_t a
Definition: asm.h:27
uint64_t c
Definition: asm.h:28
int32_t
Definition: asm.h:28
int x86_reg
Definition: asm.h:72
uint64_t b
Definition: asm.h:28