[FFmpeg-cvslog] ac3enc: add SIMD-optimized shifting functions for use with the fixed-point AC3 encoder .
Justin Ruggles
git
Tue Mar 15 16:55:23 CET 2011
ffmpeg | branch: master | Justin Ruggles <justin.ruggles at gmail.com> | Fri Mar 11 16:45:01 2011 -0500| [f1efbca5e914b28cd37cb1ea82d371acf3b96f61] | committer: Justin Ruggles
ac3enc: add SIMD-optimized shifting functions for use with the fixed-point AC3 encoder.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f1efbca5e914b28cd37cb1ea82d371acf3b96f61
---
libavcodec/ac3dsp.c | 37 +++++++++++++++++++++++++++++++++++
libavcodec/ac3dsp.h | 22 +++++++++++++++++++++
libavcodec/ac3enc_fixed.c | 41 +++-----------------------------------
libavcodec/x86/ac3dsp.asm | 45 +++++++++++++++++++++++++++++++++++++++++++
libavcodec/x86/ac3dsp_mmx.c | 12 +++++++++++
5 files changed, 120 insertions(+), 37 deletions(-)
diff --git a/libavcodec/ac3dsp.c b/libavcodec/ac3dsp.c
index da3a123..4d9db9b 100644
--- a/libavcodec/ac3dsp.c
+++ b/libavcodec/ac3dsp.c
@@ -50,10 +50,47 @@ static int ac3_max_msb_abs_int16_c(const int16_t *src, int len)
return v;
}
+static void ac3_lshift_int16_c(int16_t *src, unsigned int len,
+ unsigned int shift)
+{
+ uint32_t *src32 = (uint32_t *)src;
+ const uint32_t mask = ~(((1 << shift) - 1) << 16);
+ int i;
+ len >>= 1;
+ for (i = 0; i < len; i += 8) {
+ src32[i ] = (src32[i ] << shift) & mask;
+ src32[i+1] = (src32[i+1] << shift) & mask;
+ src32[i+2] = (src32[i+2] << shift) & mask;
+ src32[i+3] = (src32[i+3] << shift) & mask;
+ src32[i+4] = (src32[i+4] << shift) & mask;
+ src32[i+5] = (src32[i+5] << shift) & mask;
+ src32[i+6] = (src32[i+6] << shift) & mask;
+ src32[i+7] = (src32[i+7] << shift) & mask;
+ }
+}
+
+static void ac3_rshift_int32_c(int32_t *src, unsigned int len,
+ unsigned int shift)
+{
+ do {
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ *src++ >>= shift;
+ len -= 8;
+ } while (len > 0);
+}
+
av_cold void ff_ac3dsp_init(AC3DSPContext *c)
{
c->ac3_exponent_min = ac3_exponent_min_c;
c->ac3_max_msb_abs_int16 = ac3_max_msb_abs_int16_c;
+ c->ac3_lshift_int16 = ac3_lshift_int16_c;
+ c->ac3_rshift_int32 = ac3_rshift_int32_c;
if (HAVE_MMX)
ff_ac3dsp_init_x86(c);
diff --git a/libavcodec/ac3dsp.h b/libavcodec/ac3dsp.h
index a4f141f..31a0af3 100644
--- a/libavcodec/ac3dsp.h
+++ b/libavcodec/ac3dsp.h
@@ -46,6 +46,28 @@ typedef struct AC3DSPContext {
* @return a value with the same MSB as max(abs(src[]))
*/
int (*ac3_max_msb_abs_int16)(const int16_t *src, int len);
+
+ /**
+ * Left-shift each value in an array of int16_t by a specified amount.
+ * @param src input array
+ * constraints: align 16
+ * @param len number of values in the array
+ * constraints: multiple of 32 greater than 0
+ * @param shift left shift amount
+ * constraints: range [0,15]
+ */
+ void (*ac3_lshift_int16)(int16_t *src, unsigned int len, unsigned int shift);
+
+ /**
+ * Right-shift each value in an array of int32_t by a specified amount.
+ * @param src input array
+ * constraints: align 16
+ * @param len number of values in the array
+ * constraints: multiple of 16 greater than 0
+ * @param shift right shift amount
+ * constraints: range [0,31]
+ */
+ void (*ac3_rshift_int32)(int32_t *src, unsigned int len, unsigned int shift);
} AC3DSPContext;
void ff_ac3dsp_init (AC3DSPContext *c);
diff --git a/libavcodec/ac3enc_fixed.c b/libavcodec/ac3enc_fixed.c
index e750a39..d1bb429 100644
--- a/libavcodec/ac3enc_fixed.c
+++ b/libavcodec/ac3enc_fixed.c
@@ -278,40 +278,6 @@ static int log2_tab(AC3EncodeContext *s, int16_t *src, int len)
/**
- * Left-shift each value in an array by a specified amount.
- * @param tab input array
- * @param n number of values in the array
- * @param lshift left shift amount
- */
-static void lshift_tab(int16_t *tab, int n, unsigned int lshift)
-{
- int i;
-
- if (lshift > 0) {
- for (i = 0; i < n; i++)
- tab[i] <<= lshift;
- }
-}
-
-
-/**
- * Right-shift each value in an array of int32_t by a specified amount.
- * @param src input array
- * @param len number of values in the array
- * @param shift right shift amount
- */
-static void ac3_rshift_int32_c(int32_t *src, unsigned int len, unsigned int shift)
-{
- int i;
-
- if (shift > 0) {
- for (i = 0; i < len; i++)
- src[i] >>= shift;
- }
-}
-
-
-/**
* Normalize the input samples to use the maximum available precision.
* This assumes signed 16-bit input samples.
*
@@ -320,7 +286,8 @@ static void ac3_rshift_int32_c(int32_t *src, unsigned int len, unsigned int shif
static int normalize_samples(AC3EncodeContext *s)
{
int v = 14 - log2_tab(s, s->windowed_samples, AC3_WINDOW_SIZE);
- lshift_tab(s->windowed_samples, AC3_WINDOW_SIZE, v);
+ if (v > 0)
+ s->ac3dsp.ac3_lshift_int16(s->windowed_samples, AC3_WINDOW_SIZE, v);
/* +6 to right-shift from 31-bit to 25-bit */
return v + 6;
}
@@ -336,8 +303,8 @@ static void scale_coefficients(AC3EncodeContext *s)
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
AC3Block *block = &s->blocks[blk];
for (ch = 0; ch < s->channels; ch++) {
- ac3_rshift_int32_c(block->mdct_coef[ch], AC3_MAX_COEFS,
- block->coeff_shift[ch]);
+ s->ac3dsp.ac3_rshift_int32(block->mdct_coef[ch], AC3_MAX_COEFS,
+ block->coeff_shift[ch]);
}
}
}
diff --git a/libavcodec/x86/ac3dsp.asm b/libavcodec/x86/ac3dsp.asm
index b1eeca9..e281791 100644
--- a/libavcodec/x86/ac3dsp.asm
+++ b/libavcodec/x86/ac3dsp.asm
@@ -133,3 +133,48 @@ INIT_XMM
AC3_MAX_MSB_ABS_INT16 sse2, min_max
%define ABS2 ABS2_SSSE3
AC3_MAX_MSB_ABS_INT16 ssse3, or_abs
+
+;-----------------------------------------------------------------------------
+; macro used for ff_ac3_lshift_int16() and ff_ac3_rshift_int32()
+;-----------------------------------------------------------------------------
+
+%macro AC3_SHIFT 4 ; l/r, 16/32, shift instruction, instruction set
+cglobal ac3_%1shift_int%2_%4, 3,3,5, src, len, shift
+ movd m0, shiftd
+.loop:
+ mova m1, [srcq ]
+ mova m2, [srcq+mmsize ]
+ mova m3, [srcq+mmsize*2]
+ mova m4, [srcq+mmsize*3]
+ %3 m1, m0
+ %3 m2, m0
+ %3 m3, m0
+ %3 m4, m0
+ mova [srcq ], m1
+ mova [srcq+mmsize ], m2
+ mova [srcq+mmsize*2], m3
+ mova [srcq+mmsize*3], m4
+ add srcq, mmsize*4
+ sub lend, mmsize*32/%2
+ ja .loop
+.end:
+ REP_RET
+%endmacro
+
+;-----------------------------------------------------------------------------
+; void ff_ac3_lshift_int16(int16_t *src, unsigned int len, unsigned int shift)
+;-----------------------------------------------------------------------------
+
+INIT_MMX
+AC3_SHIFT l, 16, psllw, mmx
+INIT_XMM
+AC3_SHIFT l, 16, psllw, sse2
+
+;-----------------------------------------------------------------------------
+; void ff_ac3_rshift_int32(int32_t *src, unsigned int len, unsigned int shift)
+;-----------------------------------------------------------------------------
+
+INIT_MMX
+AC3_SHIFT r, 32, psrad, mmx
+INIT_XMM
+AC3_SHIFT r, 32, psrad, sse2
diff --git a/libavcodec/x86/ac3dsp_mmx.c b/libavcodec/x86/ac3dsp_mmx.c
index d8af59c..835b106 100644
--- a/libavcodec/x86/ac3dsp_mmx.c
+++ b/libavcodec/x86/ac3dsp_mmx.c
@@ -32,6 +32,12 @@ extern int ff_ac3_max_msb_abs_int16_mmxext(const int16_t *src, int len);
extern int ff_ac3_max_msb_abs_int16_sse2 (const int16_t *src, int len);
extern int ff_ac3_max_msb_abs_int16_ssse3 (const int16_t *src, int len);
+extern void ff_ac3_lshift_int16_mmx (int16_t *src, unsigned int len, unsigned int shift);
+extern void ff_ac3_lshift_int16_sse2(int16_t *src, unsigned int len, unsigned int shift);
+
+extern void ff_ac3_rshift_int32_mmx (int32_t *src, unsigned int len, unsigned int shift);
+extern void ff_ac3_rshift_int32_sse2(int32_t *src, unsigned int len, unsigned int shift);
+
av_cold void ff_ac3dsp_init_x86(AC3DSPContext *c)
{
int mm_flags = av_get_cpu_flags();
@@ -40,6 +46,8 @@ av_cold void ff_ac3dsp_init_x86(AC3DSPContext *c)
if (mm_flags & AV_CPU_FLAG_MMX) {
c->ac3_exponent_min = ff_ac3_exponent_min_mmx;
c->ac3_max_msb_abs_int16 = ff_ac3_max_msb_abs_int16_mmx;
+ c->ac3_lshift_int16 = ff_ac3_lshift_int16_mmx;
+ c->ac3_rshift_int32 = ff_ac3_rshift_int32_mmx;
}
if (mm_flags & AV_CPU_FLAG_MMX2 && HAVE_MMX2) {
c->ac3_exponent_min = ff_ac3_exponent_min_mmxext;
@@ -48,6 +56,10 @@ av_cold void ff_ac3dsp_init_x86(AC3DSPContext *c)
if (mm_flags & AV_CPU_FLAG_SSE2 && HAVE_SSE) {
c->ac3_exponent_min = ff_ac3_exponent_min_sse2;
c->ac3_max_msb_abs_int16 = ff_ac3_max_msb_abs_int16_sse2;
+ if (!(mm_flags & AV_CPU_FLAG_SSE2SLOW)) {
+ c->ac3_lshift_int16 = ff_ac3_lshift_int16_sse2;
+ c->ac3_rshift_int32 = ff_ac3_rshift_int32_sse2;
+ }
}
if (mm_flags & AV_CPU_FLAG_SSSE3 && HAVE_SSSE3) {
c->ac3_max_msb_abs_int16 = ff_ac3_max_msb_abs_int16_ssse3;
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