Index: simd/jquant-mmx.asm |
diff --git a/simd/jquant-mmx.asm b/simd/jquant-mmx.asm |
new file mode 100644 |
index 0000000000000000000000000000000000000000..dbfeceec776615c4aa52bffb754e768cb289c55d |
--- /dev/null |
+++ b/simd/jquant-mmx.asm |
@@ -0,0 +1,274 @@ |
+; |
+; jquant.asm - sample data conversion and quantization (MMX) |
+; |
+; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB |
+; |
+; Based on |
+; x86 SIMD extension for IJG JPEG library |
+; Copyright (C) 1999-2006, MIYASAKA Masaru. |
+; For conditions of distribution and use, see copyright notice in jsimdext.inc |
+; |
+; This file should be assembled with NASM (Netwide Assembler), |
+; can *not* be assembled with Microsoft's MASM or any compatible |
+; assembler (including Borland's Turbo Assembler). |
+; NASM is available from http://nasm.sourceforge.net/ or |
+; http://sourceforge.net/project/showfiles.php?group_id=6208 |
+; |
+; [TAB8] |
+ |
+%include "jsimdext.inc" |
+%include "jdct.inc" |
+ |
+; -------------------------------------------------------------------------- |
+ SECTION SEG_TEXT |
+ BITS 32 |
+; |
+; Load data into workspace, applying unsigned->signed conversion |
+; |
+; GLOBAL(void) |
+; jsimd_convsamp_mmx (JSAMPARRAY sample_data, JDIMENSION start_col, |
+; DCTELEM *workspace); |
+; |
+ |
+%define sample_data ebp+8 ; JSAMPARRAY sample_data |
+%define start_col ebp+12 ; JDIMENSION start_col |
+%define workspace ebp+16 ; DCTELEM *workspace |
+ |
+ align 16 |
+ global EXTN(jsimd_convsamp_mmx) |
+ |
+EXTN(jsimd_convsamp_mmx): |
+ push ebp |
+ mov ebp,esp |
+ push ebx |
+; push ecx ; need not be preserved |
+; push edx ; need not be preserved |
+ push esi |
+ push edi |
+ |
+ pxor mm6,mm6 ; mm6=(all 0's) |
+ pcmpeqw mm7,mm7 |
+ psllw mm7,7 ; mm7={0xFF80 0xFF80 0xFF80 0xFF80} |
+ |
+ mov esi, JSAMPARRAY [sample_data] ; (JSAMPROW *) |
+ mov eax, JDIMENSION [start_col] |
+ mov edi, POINTER [workspace] ; (DCTELEM *) |
+ mov ecx, DCTSIZE/4 |
+ alignx 16,7 |
+.convloop: |
+ mov ebx, JSAMPROW [esi+0*SIZEOF_JSAMPROW] ; (JSAMPLE *) |
+ mov edx, JSAMPROW [esi+1*SIZEOF_JSAMPROW] ; (JSAMPLE *) |
+ |
+ movq mm0, MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; mm0=(01234567) |
+ movq mm1, MMWORD [edx+eax*SIZEOF_JSAMPLE] ; mm1=(89ABCDEF) |
+ |
+ mov ebx, JSAMPROW [esi+2*SIZEOF_JSAMPROW] ; (JSAMPLE *) |
+ mov edx, JSAMPROW [esi+3*SIZEOF_JSAMPROW] ; (JSAMPLE *) |
+ |
+ movq mm2, MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; mm2=(GHIJKLMN) |
+ movq mm3, MMWORD [edx+eax*SIZEOF_JSAMPLE] ; mm3=(OPQRSTUV) |
+ |
+ movq mm4,mm0 |
+ punpcklbw mm0,mm6 ; mm0=(0123) |
+ punpckhbw mm4,mm6 ; mm4=(4567) |
+ movq mm5,mm1 |
+ punpcklbw mm1,mm6 ; mm1=(89AB) |
+ punpckhbw mm5,mm6 ; mm5=(CDEF) |
+ |
+ paddw mm0,mm7 |
+ paddw mm4,mm7 |
+ paddw mm1,mm7 |
+ paddw mm5,mm7 |
+ |
+ movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_DCTELEM)], mm0 |
+ movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_DCTELEM)], mm4 |
+ movq MMWORD [MMBLOCK(1,0,edi,SIZEOF_DCTELEM)], mm1 |
+ movq MMWORD [MMBLOCK(1,1,edi,SIZEOF_DCTELEM)], mm5 |
+ |
+ movq mm0,mm2 |
+ punpcklbw mm2,mm6 ; mm2=(GHIJ) |
+ punpckhbw mm0,mm6 ; mm0=(KLMN) |
+ movq mm4,mm3 |
+ punpcklbw mm3,mm6 ; mm3=(OPQR) |
+ punpckhbw mm4,mm6 ; mm4=(STUV) |
+ |
+ paddw mm2,mm7 |
+ paddw mm0,mm7 |
+ paddw mm3,mm7 |
+ paddw mm4,mm7 |
+ |
+ movq MMWORD [MMBLOCK(2,0,edi,SIZEOF_DCTELEM)], mm2 |
+ movq MMWORD [MMBLOCK(2,1,edi,SIZEOF_DCTELEM)], mm0 |
+ movq MMWORD [MMBLOCK(3,0,edi,SIZEOF_DCTELEM)], mm3 |
+ movq MMWORD [MMBLOCK(3,1,edi,SIZEOF_DCTELEM)], mm4 |
+ |
+ add esi, byte 4*SIZEOF_JSAMPROW |
+ add edi, byte 4*DCTSIZE*SIZEOF_DCTELEM |
+ dec ecx |
+ jnz short .convloop |
+ |
+ emms ; empty MMX state |
+ |
+ pop edi |
+ pop esi |
+; pop edx ; need not be preserved |
+; pop ecx ; need not be preserved |
+ pop ebx |
+ pop ebp |
+ ret |
+ |
+; -------------------------------------------------------------------------- |
+; |
+; Quantize/descale the coefficients, and store into coef_block |
+; |
+; This implementation is based on an algorithm described in |
+; "How to optimize for the Pentium family of microprocessors" |
+; (http://www.agner.org/assem/). |
+; |
+; GLOBAL(void) |
+; jsimd_quantize_mmx (JCOEFPTR coef_block, DCTELEM *divisors, |
+; DCTELEM *workspace); |
+; |
+ |
+%define RECIPROCAL(m,n,b) MMBLOCK(DCTSIZE*0+(m),(n),(b),SIZEOF_DCTELEM) |
+%define CORRECTION(m,n,b) MMBLOCK(DCTSIZE*1+(m),(n),(b),SIZEOF_DCTELEM) |
+%define SCALE(m,n,b) MMBLOCK(DCTSIZE*2+(m),(n),(b),SIZEOF_DCTELEM) |
+%define SHIFT(m,n,b) MMBLOCK(DCTSIZE*3+(m),(n),(b),SIZEOF_DCTELEM) |
+ |
+%define coef_block ebp+8 ; JCOEFPTR coef_block |
+%define divisors ebp+12 ; DCTELEM *divisors |
+%define workspace ebp+16 ; DCTELEM *workspace |
+ |
+ align 16 |
+ global EXTN(jsimd_quantize_mmx) |
+ |
+EXTN(jsimd_quantize_mmx): |
+ push ebp |
+ mov ebp,esp |
+; push ebx ; unused |
+; push ecx ; unused |
+; push edx ; need not be preserved |
+ push esi |
+ push edi |
+ |
+ mov esi, POINTER [workspace] |
+ mov edx, POINTER [divisors] |
+ mov edi, JCOEFPTR [coef_block] |
+ mov ah, 2 |
+ alignx 16,7 |
+.quantloop1: |
+ mov al, DCTSIZE2/8/2 |
+ alignx 16,7 |
+.quantloop2: |
+ movq mm2, MMWORD [MMBLOCK(0,0,esi,SIZEOF_DCTELEM)] |
+ movq mm3, MMWORD [MMBLOCK(0,1,esi,SIZEOF_DCTELEM)] |
+ |
+ movq mm0,mm2 |
+ movq mm1,mm3 |
+ |
+ psraw mm2,(WORD_BIT-1) ; -1 if value < 0, 0 otherwise |
+ psraw mm3,(WORD_BIT-1) |
+ |
+ pxor mm0,mm2 ; val = -val |
+ pxor mm1,mm3 |
+ psubw mm0,mm2 |
+ psubw mm1,mm3 |
+ |
+ ; |
+ ; MMX is an annoyingly crappy instruction set. It has two |
+ ; misfeatures that are causing problems here: |
+ ; |
+ ; - All multiplications are signed. |
+ ; |
+ ; - The second operand for the shifts is not treated as packed. |
+ ; |
+ ; |
+ ; We work around the first problem by implementing this algorithm: |
+ ; |
+ ; unsigned long unsigned_multiply(unsigned short x, unsigned short y) |
+ ; { |
+ ; enum { SHORT_BIT = 16 }; |
+ ; signed short sx = (signed short) x; |
+ ; signed short sy = (signed short) y; |
+ ; signed long sz; |
+ ; |
+ ; sz = (long) sx * (long) sy; /* signed multiply */ |
+ ; |
+ ; if (sx < 0) sz += (long) sy << SHORT_BIT; |
+ ; if (sy < 0) sz += (long) sx << SHORT_BIT; |
+ ; |
+ ; return (unsigned long) sz; |
+ ; } |
+ ; |
+ ; (note that a negative sx adds _sy_ and vice versa) |
+ ; |
+ ; For the second problem, we replace the shift by a multiplication. |
+ ; Unfortunately that means we have to deal with the signed issue again. |
+ ; |
+ |
+ paddw mm0, MMWORD [CORRECTION(0,0,edx)] ; correction + roundfactor |
+ paddw mm1, MMWORD [CORRECTION(0,1,edx)] |
+ |
+ movq mm4,mm0 ; store current value for later |
+ movq mm5,mm1 |
+ pmulhw mm0, MMWORD [RECIPROCAL(0,0,edx)] ; reciprocal |
+ pmulhw mm1, MMWORD [RECIPROCAL(0,1,edx)] |
+ paddw mm0,mm4 ; reciprocal is always negative (MSB=1), |
+ paddw mm1,mm5 ; so we always need to add the initial value |
+ ; (input value is never negative as we |
+ ; inverted it at the start of this routine) |
+ |
+ ; here it gets a bit tricky as both scale |
+ ; and mm0/mm1 can be negative |
+ movq mm6, MMWORD [SCALE(0,0,edx)] ; scale |
+ movq mm7, MMWORD [SCALE(0,1,edx)] |
+ movq mm4,mm0 |
+ movq mm5,mm1 |
+ pmulhw mm0,mm6 |
+ pmulhw mm1,mm7 |
+ |
+ psraw mm6,(WORD_BIT-1) ; determine if scale is negative |
+ psraw mm7,(WORD_BIT-1) |
+ |
+ pand mm6,mm4 ; and add input if it is |
+ pand mm7,mm5 |
+ paddw mm0,mm6 |
+ paddw mm1,mm7 |
+ |
+ psraw mm4,(WORD_BIT-1) ; then check if negative input |
+ psraw mm5,(WORD_BIT-1) |
+ |
+ pand mm4, MMWORD [SCALE(0,0,edx)] ; and add scale if it is |
+ pand mm5, MMWORD [SCALE(0,1,edx)] |
+ paddw mm0,mm4 |
+ paddw mm1,mm5 |
+ |
+ pxor mm0,mm2 ; val = -val |
+ pxor mm1,mm3 |
+ psubw mm0,mm2 |
+ psubw mm1,mm3 |
+ |
+ movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_DCTELEM)], mm0 |
+ movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_DCTELEM)], mm1 |
+ |
+ add esi, byte 8*SIZEOF_DCTELEM |
+ add edx, byte 8*SIZEOF_DCTELEM |
+ add edi, byte 8*SIZEOF_JCOEF |
+ dec al |
+ jnz near .quantloop2 |
+ dec ah |
+ jnz near .quantloop1 ; to avoid branch misprediction |
+ |
+ emms ; empty MMX state |
+ |
+ pop edi |
+ pop esi |
+; pop edx ; need not be preserved |
+; pop ecx ; unused |
+; pop ebx ; unused |
+ pop ebp |
+ ret |
+ |
+; For some reason, the OS X linker does not honor the request to align the |
+; segment unless we do this. |
+ align 16 |