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comparison: media/libjpeg/simd/jsimdcpu.asm
media/libjpeg/simd/jsimdcpu.asm
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| -1:000000000000 | 0:1b446c211311 |
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| 1 ; | |
| 2 ; jsimdcpu.asm - SIMD instruction support check | |
| 3 ; | |
| 4 ; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB | |
| 5 ; | |
| 6 ; Based on | |
| 7 ; x86 SIMD extension for IJG JPEG library | |
| 8 ; Copyright (C) 1999-2006, MIYASAKA Masaru. | |
| 9 ; For conditions of distribution and use, see copyright notice in jsimdext.inc | |
| 10 ; | |
| 11 ; This file should be assembled with NASM (Netwide Assembler), | |
| 12 ; can *not* be assembled with Microsoft's MASM or any compatible | |
| 13 ; assembler (including Borland's Turbo Assembler). | |
| 14 ; NASM is available from http://nasm.sourceforge.net/ or | |
| 15 ; http://sourceforge.net/project/showfiles.php?group_id=6208 | |
| 16 ; | |
| 17 ; [TAB8] | |
| 18 | |
| 19 %include "jsimdext.inc" | |
| 20 | |
| 21 ; -------------------------------------------------------------------------- | |
| 22 SECTION SEG_TEXT | |
| 23 BITS 32 | |
| 24 ; | |
| 25 ; Check if the CPU supports SIMD instructions | |
| 26 ; | |
| 27 ; GLOBAL(unsigned int) | |
| 28 ; jpeg_simd_cpu_support (void) | |
| 29 ; | |
| 30 | |
| 31 align 16 | |
| 32 global EXTN(jpeg_simd_cpu_support) | |
| 33 | |
| 34 EXTN(jpeg_simd_cpu_support): | |
| 35 push ebx | |
| 36 ; push ecx ; need not be preserved | |
| 37 ; push edx ; need not be preserved | |
| 38 ; push esi ; unused | |
| 39 push edi | |
| 40 | |
| 41 xor edi,edi ; simd support flag | |
| 42 | |
| 43 pushfd | |
| 44 pop eax | |
| 45 mov edx,eax | |
| 46 xor eax, 1<<21 ; flip ID bit in EFLAGS | |
| 47 push eax | |
| 48 popfd | |
| 49 pushfd | |
| 50 pop eax | |
| 51 xor eax,edx | |
| 52 jz short .return ; CPUID is not supported | |
| 53 | |
| 54 ; Check for MMX instruction support | |
| 55 xor eax,eax | |
| 56 cpuid | |
| 57 test eax,eax | |
| 58 jz short .return | |
| 59 | |
| 60 xor eax,eax | |
| 61 inc eax | |
| 62 cpuid | |
| 63 mov eax,edx ; eax = Standard feature flags | |
| 64 | |
| 65 test eax, 1<<23 ; bit23:MMX | |
| 66 jz short .no_mmx | |
| 67 or edi, byte JSIMD_MMX | |
| 68 .no_mmx: | |
| 69 test eax, 1<<25 ; bit25:SSE | |
| 70 jz short .no_sse | |
| 71 or edi, byte JSIMD_SSE | |
| 72 .no_sse: | |
| 73 test eax, 1<<26 ; bit26:SSE2 | |
| 74 jz short .no_sse2 | |
| 75 or edi, byte JSIMD_SSE2 | |
| 76 .no_sse2: | |
| 77 | |
| 78 ; Check for 3DNow! instruction support | |
| 79 mov eax, 0x80000000 | |
| 80 cpuid | |
| 81 cmp eax, 0x80000000 | |
| 82 jbe short .return | |
| 83 | |
| 84 mov eax, 0x80000001 | |
| 85 cpuid | |
| 86 mov eax,edx ; eax = Extended feature flags | |
| 87 | |
| 88 test eax, 1<<31 ; bit31:3DNow!(vendor independent) | |
| 89 jz short .no_3dnow | |
| 90 or edi, byte JSIMD_3DNOW | |
| 91 .no_3dnow: | |
| 92 | |
| 93 .return: | |
| 94 mov eax,edi | |
| 95 | |
| 96 pop edi | |
| 97 ; pop esi ; unused | |
| 98 ; pop edx ; need not be preserved | |
| 99 ; pop ecx ; need not be preserved | |
| 100 pop ebx | |
| 101 ret | |
| 102 | |
| 103 ; For some reason, the OS X linker does not honor the request to align the | |
| 104 ; segment unless we do this. | |
| 105 align 16 |
