[Ffmpeg-devel] [RFC] AltiVec optimizations, try 2

Kostya kostya.shishkov
Tue Aug 1 06:29:08 CEST 2006


Here is my second attempt of writing optimized code. Please test how it works on your Macs (my rough test show ~6% speedup).
If there are no objections I'll commit it tomorrow.
-------------- next part --------------
diff -ru --exclude .svn ffmpeg/libavcodec/Makefile ffmpeg-vc1/libavcodec/Makefile
--- ffmpeg/libavcodec/Makefile	2006-07-27 18:22:18.000000000 +0300
+++ ffmpeg-vc1/libavcodec/Makefile	2006-07-31 11:51:57.000000000 +0300
@@ -341,7 +344,8 @@
                                           ppc/gmc_altivec.o          \
                                           ppc/fdct_altivec.o         \
                                           ppc/dsputil_h264_altivec.o \
-                                          ppc/dsputil_snow_altivec.o
+                                          ppc/dsputil_snow_altivec.o \
+                                          ppc/vc1dsp_altivec.o
 
 CFLAGS += $(CFLAGS-yes)
 OBJS += $(OBJS-yes)
diff -ru --exclude .svn ffmpeg/libavcodec/ppc/dsputil_ppc.c ffmpeg-vc1/libavcodec/ppc/dsputil_ppc.c
--- ffmpeg/libavcodec/ppc/dsputil_ppc.c	2006-07-27 18:22:09.000000000 +0300
+++ ffmpeg-vc1/libavcodec/ppc/dsputil_ppc.c	2006-07-31 11:51:04.000000000 +0300
@@ -251,6 +251,10 @@
 
 void dsputil_h264_init_ppc(DSPContext* c, AVCodecContext *avctx);
 
+#ifdef HAVE_ALTIVEC
+void vc1dsp_init_altivec(DSPContext* c, AVCodecContext *avctx);
+#endif
+
 void dsputil_init_ppc(DSPContext* c, AVCodecContext *avctx)
 {
     // Common optimizations whether Altivec is available or not
@@ -311,6 +315,7 @@
         c->vertical_compose97i = ff_snow_vertical_compose97i_altivec;
         c->inner_add_yblock = ff_snow_inner_add_yblock_altivec;
 
+        vc1dsp_init_altivec(c, avctx);
 #ifdef CONFIG_ENCODERS
         if (avctx->dct_algo == FF_DCT_AUTO ||
             avctx->dct_algo == FF_DCT_ALTIVEC)
diff -ru --exclude .svn ffmpeg/libavcodec/ppc/vc1dsp_altivec.c ffmpeg-vc1/libavcodec/ppc/vc1dsp_altivec.c
--- ffmpeg/libavcodec/ppc/vc1dsp_altivec.c	2006-07-31 13:38:38.000000000 +0300
+++ ffmpeg-vc1/libavcodec/ppc/vc1dsp_altivec.c	2006-07-31 13:28:11.000000000 +0300
@@ -0,0 +1,361 @@
+/*
+ * VC-1 and WMV3 decoder - DSP functions AltiVec-optimized
+ * Copyright (c) 2006 Konstantin Shishkov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#include "../dsputil.h"
+
+#include "gcc_fixes.h"
+
+#include "dsputil_altivec.h"
+
+/* constants used in transform */
+static const vector int vec_64 = (vector int)64;
+static const vector int vec_7 = (vector int)7;
+static const vector int vec_5 = (vector int)5;
+static const vector int vec_4 = (vector int)4;
+static const vector int vec_3 = (vector int)3;
+static const vector int vec_2 = (vector int)2;
+static const vector int vec_1 = (vector int)1;
+
+// Transpose 8x8 matrix of 16-bit elements. Borrowed from mpegvideo_altivec.c
+#define TRANSPOSE8(a,b,c,d,e,f,g,h) \
+do { \
+    vector signed short A1, B1, C1, D1, E1, F1, G1, H1; \
+    vector signed short A2, B2, C2, D2, E2, F2, G2, H2; \
+ \
+    A1 = vec_mergeh (a, e); \
+    B1 = vec_mergel (a, e); \
+    C1 = vec_mergeh (b, f); \
+    D1 = vec_mergel (b, f); \
+    E1 = vec_mergeh (c, g); \
+    F1 = vec_mergel (c, g); \
+    G1 = vec_mergeh (d, h); \
+    H1 = vec_mergel (d, h); \
+ \
+    A2 = vec_mergeh (A1, E1); \
+    B2 = vec_mergel (A1, E1); \
+    C2 = vec_mergeh (B1, F1); \
+    D2 = vec_mergel (B1, F1); \
+    E2 = vec_mergeh (C1, G1); \
+    F2 = vec_mergel (C1, G1); \
+    G2 = vec_mergeh (D1, H1); \
+    H2 = vec_mergel (D1, H1); \
+ \
+    a = vec_mergeh (A2, E2); \
+    b = vec_mergel (A2, E2); \
+    c = vec_mergeh (B2, F2); \
+    d = vec_mergel (B2, F2); \
+    e = vec_mergeh (C2, G2); \
+    f = vec_mergel (C2, G2); \
+    g = vec_mergeh (D2, H2); \
+    h = vec_mergel (D2, H2); \
+} while (0)
+
+// main steps of 8x8 transform
+#define STEP8(s0, s1, s2, s3, s4, s5, s6, s7, vec_rnd) \
+do { \
+    t0 = vec_sl(vec_add(s0, s4), vec_2); \
+    t0 = vec_add(vec_sl(t0, vec_1), t0); \
+    t0 = vec_add(t0, vec_rnd); \
+    t1 = vec_sl(vec_sub(s0, s4), vec_2); \
+    t1 = vec_add(vec_sl(t1, vec_1), t1); \
+    t1 = vec_add(t1, vec_rnd); \
+    t2 = vec_add(vec_sl(s6, vec_2), vec_sl(s6, vec_1)); \
+    t2 = vec_add(t2, vec_sl(s2, vec_4)); \
+    t3 = vec_add(vec_sl(s2, vec_2), vec_sl(s2, vec_1)); \
+    t3 = vec_sub(t3, vec_sl(s6, vec_4)); \
+    t4 = vec_add(t0, t2); \
+    t5 = vec_add(t1, t3); \
+    t6 = vec_sub(t1, t3); \
+    t7 = vec_sub(t0, t2); \
+\
+    t0 = vec_sl(vec_add(s1, s3), vec_4); \
+    t0 = vec_add(t0, vec_sl(s5, vec_3)); \
+    t0 = vec_add(t0, vec_sl(s7, vec_2)); \
+    t0 = vec_add(t0, vec_sub(s5, s3)); \
+\
+    t1 = vec_sl(vec_sub(s1, s5), vec_4); \
+    t1 = vec_sub(t1, vec_sl(s7, vec_3)); \
+    t1 = vec_sub(t1, vec_sl(s3, vec_2)); \
+    t1 = vec_sub(t1, vec_add(s1, s7)); \
+\
+    t2 = vec_sl(vec_sub(s7, s3), vec_4); \
+    t2 = vec_add(t2, vec_sl(s1, vec_3)); \
+    t2 = vec_add(t2, vec_sl(s5, vec_2)); \
+    t2 = vec_add(t2, vec_sub(s1, s7)); \
+\
+    t3 = vec_sl(vec_sub(s5, s7), vec_4); \
+    t3 = vec_sub(t3, vec_sl(s3, vec_3)); \
+    t3 = vec_add(t3, vec_sl(s1, vec_2)); \
+    t3 = vec_sub(t3, vec_add(s3, s5)); \
+\
+    s0 = vec_add(t4, t0); \
+    s1 = vec_add(t5, t1); \
+    s2 = vec_add(t6, t2); \
+    s3 = vec_add(t7, t3); \
+    s4 = vec_sub(t7, t3); \
+    s5 = vec_sub(t6, t2); \
+    s6 = vec_sub(t5, t1); \
+    s7 = vec_sub(t4, t0); \
+}while(0)
+
+#define SHIFT_HOR8(s0, s1, s2, s3, s4, s5, s6, s7) \
+do { \
+    s0 = vec_sra(s0, vec_3); \
+    s1 = vec_sra(s1, vec_3); \
+    s2 = vec_sra(s2, vec_3); \
+    s3 = vec_sra(s3, vec_3); \
+    s4 = vec_sra(s4, vec_3); \
+    s5 = vec_sra(s5, vec_3); \
+    s6 = vec_sra(s6, vec_3); \
+    s7 = vec_sra(s7, vec_3); \
+}while(0)
+
+#define SHIFT_VERT8(s0, s1, s2, s3, s4, s5, s6, s7) \
+do { \
+    s0 = vec_sra(s0, vec_7); \
+    s1 = vec_sra(s1, vec_7); \
+    s2 = vec_sra(s2, vec_7); \
+    s3 = vec_sra(s3, vec_7); \
+    s4 = vec_sra(vec_add(s4, vec_1), vec_7); \
+    s5 = vec_sra(vec_add(s5, vec_1), vec_7); \
+    s6 = vec_sra(vec_add(s6, vec_1), vec_7); \
+    s7 = vec_sra(vec_add(s7, vec_1), vec_7); \
+}while(0)
+
+/* main steps of 4x4 transform */
+#define STEP4(s0, s1, s2, s3, vec_rnd) \
+do { \
+    t1 = vec_add(vec_sl(s0, vec_4), s0); \
+    t1 = vec_add(t1, vec_rnd); \
+    t2 = vec_add(vec_sl(s2, vec_4), s2); \
+    t0 = vec_add(t1, t2); \
+    t1 = vec_sub(t1, t2); \
+    t3 = vec_sl(vec_sub(s3, s1), vec_1); \
+    t3 = vec_add(t3, vec_sl(t3, vec_2)); \
+    t2 = vec_add(t3, vec_sl(s1, vec_5)); \
+    t3 = vec_add(t3, vec_sl(s3, vec_3)); \
+    t3 = vec_add(t3, vec_sl(s3, vec_2)); \
+    s0 = vec_add(t0, t2); \
+    s1 = vec_sub(t1, t3); \
+    s2 = vec_add(t1, t3); \
+    s3 = vec_sub(t0, t2); \
+}while (0)
+
+#define SHIFT_HOR4(s0, s1, s2, s3) \
+    s0 = vec_sra(s0, vec_3); \
+    s1 = vec_sra(s1, vec_3); \
+    s2 = vec_sra(s2, vec_3); \
+    s3 = vec_sra(s3, vec_3);
+
+#define SHIFT_VERT4(s0, s1, s2, s3) \
+    s0 = vec_sra(s0, vec_7); \
+    s1 = vec_sra(s1, vec_7); \
+    s2 = vec_sra(s2, vec_7); \
+    s3 = vec_sra(s3, vec_7);
+
+/** Do inverse transform on 8x8 block
+*/
+static void vc1_inv_trans_8x8_altivec(DCTELEM block[64])
+{
+    vector signed short src0, src1, src2, src3, src4, src5, src6, src7;
+    vector int s0, s1, s2, s3, s4, s5, s6, s7;
+    vector int s8, s9, sA, sB, sC, sD, sE, sF;
+    vector int t0, t1, t2, t3, t4, t5, t6, t7;
+
+    src0 = vec_ld(  0, block);
+    src1 = vec_ld( 16, block);
+    src2 = vec_ld( 32, block);
+    src3 = vec_ld( 48, block);
+    src4 = vec_ld( 64, block);
+    src5 = vec_ld( 80, block);
+    src6 = vec_ld( 96, block);
+    src7 = vec_ld(112, block);
+
+    TRANSPOSE8(src0, src1, src2, src3, src4, src5, src6, src7);
+    s0 = vec_unpackl(src0);
+    s1 = vec_unpackl(src1);
+    s2 = vec_unpackl(src2);
+    s3 = vec_unpackl(src3);
+    s4 = vec_unpackl(src4);
+    s5 = vec_unpackl(src5);
+    s6 = vec_unpackl(src6);
+    s7 = vec_unpackl(src7);
+    s8 = vec_unpackh(src0);
+    s9 = vec_unpackh(src1);
+    sA = vec_unpackh(src2);
+    sB = vec_unpackh(src3);
+    sC = vec_unpackh(src4);
+    sD = vec_unpackh(src5);
+    sE = vec_unpackh(src6);
+    sF = vec_unpackh(src7);
+    STEP8(s0, s1, s2, s3, s4, s5, s6, s7, vec_4);
+    SHIFT_HOR8(s0, s1, s2, s3, s4, s5, s6, s7);
+    STEP8(s8, s9, sA, sB, sC, sD, sE, sF, vec_4);
+    SHIFT_HOR8(s8, s9, sA, sB, sC, sD, sE, sF);
+    src0 = vec_pack(s8, s0);
+    src1 = vec_pack(s9, s1);
+    src2 = vec_pack(sA, s2);
+    src3 = vec_pack(sB, s3);
+    src4 = vec_pack(sC, s4);
+    src5 = vec_pack(sD, s5);
+    src6 = vec_pack(sE, s6);
+    src7 = vec_pack(sF, s7);
+    TRANSPOSE8(src0, src1, src2, src3, src4, src5, src6, src7);
+
+    s0 = vec_unpackl(src0);
+    s1 = vec_unpackl(src1);
+    s2 = vec_unpackl(src2);
+    s3 = vec_unpackl(src3);
+    s4 = vec_unpackl(src4);
+    s5 = vec_unpackl(src5);
+    s6 = vec_unpackl(src6);
+    s7 = vec_unpackl(src7);
+    s8 = vec_unpackh(src0);
+    s9 = vec_unpackh(src1);
+    sA = vec_unpackh(src2);
+    sB = vec_unpackh(src3);
+    sC = vec_unpackh(src4);
+    sD = vec_unpackh(src5);
+    sE = vec_unpackh(src6);
+    sF = vec_unpackh(src7);
+    STEP8(s0, s1, s2, s3, s4, s5, s6, s7, vec_64);
+    SHIFT_VERT8(s0, s1, s2, s3, s4, s5, s6, s7);
+    STEP8(s8, s9, sA, sB, sC, sD, sE, sF, vec_64);
+    SHIFT_VERT8(s8, s9, sA, sB, sC, sD, sE, sF);
+    src0 = vec_pack(s8, s0);
+    src1 = vec_pack(s9, s1);
+    src2 = vec_pack(sA, s2);
+    src3 = vec_pack(sB, s3);
+    src4 = vec_pack(sC, s4);
+    src5 = vec_pack(sD, s5);
+    src6 = vec_pack(sE, s6);
+    src7 = vec_pack(sF, s7);
+
+    vec_st(src0,  0, block);
+    vec_st(src1, 16, block);
+    vec_st(src2, 32, block);
+    vec_st(src3, 48, block);
+    vec_st(src4, 64, block);
+    vec_st(src5, 80, block);
+    vec_st(src6, 96, block);
+    vec_st(src7,112, block);
+}
+
+/** Do inverse transform on 8x4 part of block
+*/
+static void vc1_inv_trans_8x4_altivec(DCTELEM block[64], int n)
+{
+    vector signed short src0, src1, src2, src3, src4, src5, src6, src7;
+    vector int s0, s1, s2, s3, s4, s5, s6, s7;
+    vector int s8, s9, sA, sB, sC, sD, sE, sF;
+    vector int t0, t1, t2, t3, t4, t5, t6, t7;
+
+    src0 = vec_ld(  0, block);
+    src1 = vec_ld( 16, block);
+    src2 = vec_ld( 32, block);
+    src3 = vec_ld( 48, block);
+    src4 = vec_ld( 64, block);
+    src5 = vec_ld( 80, block);
+    src6 = vec_ld( 96, block);
+    src7 = vec_ld(112, block);
+
+    TRANSPOSE8(src0, src1, src2, src3, src4, src5, src6, src7);
+    s0 = vec_unpackl(src0);
+    s1 = vec_unpackl(src1);
+    s2 = vec_unpackl(src2);
+    s3 = vec_unpackl(src3);
+    s4 = vec_unpackl(src4);
+    s5 = vec_unpackl(src5);
+    s6 = vec_unpackl(src6);
+    s7 = vec_unpackl(src7);
+    s8 = vec_unpackh(src0);
+    s9 = vec_unpackh(src1);
+    sA = vec_unpackh(src2);
+    sB = vec_unpackh(src3);
+    sC = vec_unpackh(src4);
+    sD = vec_unpackh(src5);
+    sE = vec_unpackh(src6);
+    sF = vec_unpackh(src7);
+    STEP8(s0, s1, s2, s3, s4, s5, s6, s7, vec_4);
+    SHIFT_HOR8(s0, s1, s2, s3, s4, s5, s6, s7);
+    STEP8(s8, s9, sA, sB, sC, sD, sE, sF, vec_4);
+    SHIFT_HOR8(s8, s9, sA, sB, sC, sD, sE, sF);
+    src0 = vec_pack(s8, s0);
+    src1 = vec_pack(s9, s1);
+    src2 = vec_pack(sA, s2);
+    src3 = vec_pack(sB, s3);
+    src4 = vec_pack(sC, s4);
+    src5 = vec_pack(sD, s5);
+    src6 = vec_pack(sE, s6);
+    src7 = vec_pack(sF, s7);
+    TRANSPOSE8(src0, src1, src2, src3, src4, src5, src6, src7);
+
+    if(!n){ // upper half of block
+        s0 = vec_unpackh(src0);
+        s1 = vec_unpackh(src1);
+        s2 = vec_unpackh(src2);
+        s3 = vec_unpackh(src3);
+        s8 = vec_unpackl(src0);
+        s9 = vec_unpackl(src1);
+        sA = vec_unpackl(src2);
+        sB = vec_unpackl(src3);
+        STEP4(s0, s1, s2, s3, vec_64);
+        SHIFT_VERT4(s0, s1, s2, s3);
+        STEP4(s8, s9, sA, sB, vec_64);
+        SHIFT_VERT4(s8, s9, sA, sB);
+        src0 = vec_pack(s0, s8);
+        src1 = vec_pack(s1, s9);
+        src2 = vec_pack(s2, sA);
+        src3 = vec_pack(s3, sB);
+
+        vec_st(src0,  0, block);
+        vec_st(src1, 16, block);
+        vec_st(src2, 32, block);
+        vec_st(src3, 48, block);
+    } else { //lower half of block
+        s0 = vec_unpackh(src4);
+        s1 = vec_unpackh(src5);
+        s2 = vec_unpackh(src6);
+        s3 = vec_unpackh(src7);
+        s8 = vec_unpackl(src4);
+        s9 = vec_unpackl(src5);
+        sA = vec_unpackl(src6);
+        sB = vec_unpackl(src7);
+        STEP4(s0, s1, s2, s3, vec_64);
+        SHIFT_VERT4(s0, s1, s2, s3);
+        STEP4(s8, s9, sA, sB, vec_64);
+        SHIFT_VERT4(s8, s9, sA, sB);
+        src4 = vec_pack(s0, s8);
+        src5 = vec_pack(s1, s9);
+        src6 = vec_pack(s2, sA);
+        src7 = vec_pack(s3, sB);
+
+        vec_st(src4, 64, block);
+        vec_st(src5, 80, block);
+        vec_st(src6, 96, block);
+        vec_st(src7,112, block);
+    }
+}
+
+
+void vc1dsp_init_altivec(DSPContext* dsp, AVCodecContext *avctx) {
+    dsp->vc1_inv_trans_8x8 = vc1_inv_trans_8x8_altivec;
+    dsp->vc1_inv_trans_8x4 = vc1_inv_trans_8x4_altivec;
+}



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