Source code
Revision control
Copy as Markdown
Other Tools
;
; jquanti.asm - sample data conversion and quantization (SSE2)
;
; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
; Copyright (C) 2016, 2024, D. R. Commander.
;
; Based on the 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) or Yasm.
%include "jsimdext.inc"
%include "jdct.inc"
; --------------------------------------------------------------------------
SECTION SEG_TEXT
BITS 32
;
; Load data into workspace, applying unsigned->signed conversion
;
; GLOBAL(void)
; jsimd_convsamp_sse2(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 32
GLOBAL_FUNCTION(jsimd_convsamp_sse2)
EXTN(jsimd_convsamp_sse2):
push ebp
mov ebp, esp
push ebx
; push ecx ; need not be preserved
; push edx ; need not be preserved
push esi
push edi
pxor xmm6, xmm6 ; xmm6=(all 0's)
pcmpeqw xmm7, xmm7
psllw xmm7, 7 ; xmm7={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 xmm0, XMM_MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; xmm0=(01234567)
movq xmm1, XMM_MMWORD [edx+eax*SIZEOF_JSAMPLE] ; xmm1=(89ABCDEF)
mov ebx, JSAMPROW [esi+2*SIZEOF_JSAMPROW] ; (JSAMPLE *)
mov edx, JSAMPROW [esi+3*SIZEOF_JSAMPROW] ; (JSAMPLE *)
movq xmm2, XMM_MMWORD [ebx+eax*SIZEOF_JSAMPLE] ; xmm2=(GHIJKLMN)
movq xmm3, XMM_MMWORD [edx+eax*SIZEOF_JSAMPLE] ; xmm3=(OPQRSTUV)
punpcklbw xmm0, xmm6 ; xmm0=(01234567)
punpcklbw xmm1, xmm6 ; xmm1=(89ABCDEF)
paddw xmm0, xmm7
paddw xmm1, xmm7
punpcklbw xmm2, xmm6 ; xmm2=(GHIJKLMN)
punpcklbw xmm3, xmm6 ; xmm3=(OPQRSTUV)
paddw xmm2, xmm7
paddw xmm3, xmm7
movdqa XMMWORD [XMMBLOCK(0,0,edi,SIZEOF_DCTELEM)], xmm0
movdqa XMMWORD [XMMBLOCK(1,0,edi,SIZEOF_DCTELEM)], xmm1
movdqa XMMWORD [XMMBLOCK(2,0,edi,SIZEOF_DCTELEM)], xmm2
movdqa XMMWORD [XMMBLOCK(3,0,edi,SIZEOF_DCTELEM)], xmm3
add esi, byte 4*SIZEOF_JSAMPROW
add edi, byte 4*DCTSIZE*SIZEOF_DCTELEM
dec ecx
jnz short .convloop
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
; "Optimizing subroutines in assembly language:
;
; GLOBAL(void)
; jsimd_quantize_sse2(JCOEFPTR coef_block, DCTELEM *divisors,
; DCTELEM *workspace);
;
%define RECIPROCAL(m, n, b) \
XMMBLOCK(DCTSIZE * 0 + (m), (n), (b), SIZEOF_DCTELEM)
%define CORRECTION(m, n, b) \
XMMBLOCK(DCTSIZE * 1 + (m), (n), (b), SIZEOF_DCTELEM)
%define SCALE(m, n, b) \
XMMBLOCK(DCTSIZE * 2 + (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 32
GLOBAL_FUNCTION(jsimd_quantize_sse2)
EXTN(jsimd_quantize_sse2):
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 eax, DCTSIZE2/32
ALIGNX 16, 7
.quantloop:
movdqa xmm4, XMMWORD [XMMBLOCK(0,0,esi,SIZEOF_DCTELEM)]
movdqa xmm5, XMMWORD [XMMBLOCK(1,0,esi,SIZEOF_DCTELEM)]
movdqa xmm6, XMMWORD [XMMBLOCK(2,0,esi,SIZEOF_DCTELEM)]
movdqa xmm7, XMMWORD [XMMBLOCK(3,0,esi,SIZEOF_DCTELEM)]
movdqa xmm0, xmm4
movdqa xmm1, xmm5
movdqa xmm2, xmm6
movdqa xmm3, xmm7
psraw xmm4, (WORD_BIT-1)
psraw xmm5, (WORD_BIT-1)
psraw xmm6, (WORD_BIT-1)
psraw xmm7, (WORD_BIT-1)
pxor xmm0, xmm4
pxor xmm1, xmm5
pxor xmm2, xmm6
pxor xmm3, xmm7
psubw xmm0, xmm4 ; if (xmm0 < 0) xmm0 = -xmm0;
psubw xmm1, xmm5 ; if (xmm1 < 0) xmm1 = -xmm1;
psubw xmm2, xmm6 ; if (xmm2 < 0) xmm2 = -xmm2;
psubw xmm3, xmm7 ; if (xmm3 < 0) xmm3 = -xmm3;
paddw xmm0, XMMWORD [CORRECTION(0,0,edx)] ; correction + roundfactor
paddw xmm1, XMMWORD [CORRECTION(1,0,edx)]
paddw xmm2, XMMWORD [CORRECTION(2,0,edx)]
paddw xmm3, XMMWORD [CORRECTION(3,0,edx)]
pmulhuw xmm0, XMMWORD [RECIPROCAL(0,0,edx)] ; reciprocal
pmulhuw xmm1, XMMWORD [RECIPROCAL(1,0,edx)]
pmulhuw xmm2, XMMWORD [RECIPROCAL(2,0,edx)]
pmulhuw xmm3, XMMWORD [RECIPROCAL(3,0,edx)]
pmulhuw xmm0, XMMWORD [SCALE(0,0,edx)] ; scale
pmulhuw xmm1, XMMWORD [SCALE(1,0,edx)]
pmulhuw xmm2, XMMWORD [SCALE(2,0,edx)]
pmulhuw xmm3, XMMWORD [SCALE(3,0,edx)]
pxor xmm0, xmm4
pxor xmm1, xmm5
pxor xmm2, xmm6
pxor xmm3, xmm7
psubw xmm0, xmm4
psubw xmm1, xmm5
psubw xmm2, xmm6
psubw xmm3, xmm7
movdqa XMMWORD [XMMBLOCK(0,0,edi,SIZEOF_DCTELEM)], xmm0
movdqa XMMWORD [XMMBLOCK(1,0,edi,SIZEOF_DCTELEM)], xmm1
movdqa XMMWORD [XMMBLOCK(2,0,edi,SIZEOF_DCTELEM)], xmm2
movdqa XMMWORD [XMMBLOCK(3,0,edi,SIZEOF_DCTELEM)], xmm3
add esi, byte 32*SIZEOF_DCTELEM
add edx, byte 32*SIZEOF_DCTELEM
add edi, byte 32*SIZEOF_JCOEF
dec eax
jnz near .quantloop
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 32