FFmpeg
asmdefs.h
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1 /*
2  * Copyright (c) 2015 Imagination Technologies Ltd
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 /**
22  * @file
23  * MIPS assembly defines from sys/asm.h but rewritten for use with C inline
24  * assembly (rather than from within .s files).
25  */
26 
27 #ifndef AVUTIL_MIPS_ASMDEFS_H
28 #define AVUTIL_MIPS_ASMDEFS_H
29 
30 #if defined(_ABI64) && _MIPS_SIM == _ABI64
31 # define mips_reg int64_t
32 # define PTRSIZE " 8 "
33 # define PTRLOG " 3 "
34 # define PTR_ADDU "daddu "
35 # define PTR_ADDIU "daddiu "
36 # define PTR_ADDI "daddi "
37 # define PTR_SUBU "dsubu "
38 # define PTR_L "ld "
39 # define PTR_S "sd "
40 # define PTR_SRA "dsra "
41 # define PTR_SRL "dsrl "
42 # define PTR_SLL "dsll "
43 #else
44 # define mips_reg int32_t
45 # define PTRSIZE " 4 "
46 # define PTRLOG " 2 "
47 # define PTR_ADDU "addu "
48 # define PTR_ADDIU "addiu "
49 # define PTR_ADDI "addi "
50 # define PTR_SUBU "subu "
51 # define PTR_L "lw "
52 # define PTR_S "sw "
53 # define PTR_SRA "sra "
54 # define PTR_SRL "srl "
55 # define PTR_SLL "sll "
56 #endif
57 
58 /*
59  * parse_r var, r - Helper assembler macro for parsing register names.
60  *
61  * This converts the register name in $n form provided in \r to the
62  * corresponding register number, which is assigned to the variable \var. It is
63  * needed to allow explicit encoding of instructions in inline assembly where
64  * registers are chosen by the compiler in $n form, allowing us to avoid using
65  * fixed register numbers.
66  *
67  * It also allows newer instructions (not implemented by the assembler) to be
68  * transparently implemented using assembler macros, instead of needing separate
69  * cases depending on toolchain support.
70  *
71  * Simple usage example:
72  * __asm__ __volatile__("parse_r __rt, %0\n\t"
73  * ".insn\n\t"
74  * "# di %0\n\t"
75  * ".word (0x41606000 | (__rt << 16))"
76  * : "=r" (status);
77  */
78 
79 /* Match an individual register number and assign to \var */
80 #define _IFC_REG(n) \
81  ".ifc \\r, $" #n "\n\t" \
82  "\\var = " #n "\n\t" \
83  ".endif\n\t"
84 
85 __asm__(".macro parse_r var r\n\t"
86  "\\var = -1\n\t"
89  _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11)
90  _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15)
91  _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19)
92  _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23)
93  _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27)
94  _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31)
95  ".iflt \\var\n\t"
96  ".error \"Unable to parse register name \\r\"\n\t"
97  ".endif\n\t"
98  ".endm");
99 
100 #endif /* AVCODEC_MIPS_ASMDEFS_H */
#define _IFC_REG(n)
Definition: asmdefs.h:80
__asm__(".macro parse_r var r\n\t""\\var = -1\n\t"_IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31)".iflt \\var\n\t"".error \"Unable to parse register name \\r\"\n\t"".endif\n\t"".endm")