xref: /third_party/ffmpeg/libavutil/x86/asm.h (revision cabdff1a) 
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
27typedef struct xmm_reg { uint64_t a, b; } xmm_reg;
28typedef struct ymm_reg { uint64_t a, b, c, d; } ymm_reg;
29
30#if ARCH_X86_64
31#    define FF_OPSIZE "q"
32#    define FF_REG_a "rax"
33#    define FF_REG_b "rbx"
34#    define FF_REG_c "rcx"
35#    define FF_REG_d "rdx"
36#    define FF_REG_D "rdi"
37#    define FF_REG_S "rsi"
38#    define FF_PTR_SIZE "8"
39typedef int64_t x86_reg;
40
41/* FF_REG_SP is defined in Solaris sys headers, so use FF_REG_sp */
42#    define FF_REG_sp "rsp"
43#    define FF_REG_BP "rbp"
44#    define FF_REGBP   rbp
45#    define FF_REGa    rax
46#    define FF_REGb    rbx
47#    define FF_REGc    rcx
48#    define FF_REGd    rdx
49#    define FF_REGSP   rsp
50
51#elif ARCH_X86_32
52
53#    define FF_OPSIZE "l"
54#    define FF_REG_a "eax"
55#    define FF_REG_b "ebx"
56#    define FF_REG_c "ecx"
57#    define FF_REG_d "edx"
58#    define FF_REG_D "edi"
59#    define FF_REG_S "esi"
60#    define FF_PTR_SIZE "4"
61typedef int32_t x86_reg;
62
63#    define FF_REG_sp "esp"
64#    define FF_REG_BP "ebp"
65#    define FF_REGBP   ebp
66#    define FF_REGa    eax
67#    define FF_REGb    ebx
68#    define FF_REGc    ecx
69#    define FF_REGd    edx
70#    define FF_REGSP   esp
71#else
72typedef 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 */
155