[FFmpeg-cvslog] Revert "ac3enc: add SIMD-optimized shifting functions for use with the fixed-point AC3 encoder "

Michael Niedermayer git
Tue Mar 15 16:55:32 CET 2011


ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Tue Mar 15 15:11:22 2011 +0100| [f7a5e7791dda0b26df198f301db5605555a7a9d3] | committer: Michael Niedermayer

Revert "ac3enc: add SIMD-optimized shifting functions for use with the fixed-point AC3 encoder"

This reverts commit cc4d3dd3e2171f63cd4297292349b58788fff260.
revert at authors request due to better impementation being available

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f7a5e7791dda0b26df198f301db5605555a7a9d3
---

 libavcodec/ac3dsp.c         |   26 ---------------
 libavcodec/ac3dsp.h         |   22 -------------
 libavcodec/ac3enc_fixed.c   |   44 ++++++++++++++++++++++++--
 libavcodec/x86/ac3dsp.asm   |   74 -------------------------------------------
 libavcodec/x86/ac3dsp_mmx.c |   13 -------
 5 files changed, 41 insertions(+), 138 deletions(-)

diff --git a/libavcodec/ac3dsp.c b/libavcodec/ac3dsp.c
index 05b1aa8..da3a123 100644
--- a/libavcodec/ac3dsp.c
+++ b/libavcodec/ac3dsp.c
@@ -50,36 +50,10 @@ 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, int len, unsigned int shift)
-{
-    int i;
-
-    if (shift > 0) {
-        for (i = 0; i < len; i++)
-            src[i] <<= shift;
-    }
-}
-
-static void ac3_shift_int32_c(int32_t *src, int len, int shift)
-{
-    int i;
-
-    if (shift > 0) {
-        for (i = 0; i < len; i++)
-            src[i] <<= shift;
-    } else if (shift < 0) {
-        shift = -shift;
-        for (i = 0; i < len; i++)
-            src[i] >>= shift;
-    }
-}
-
 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_shift_int32  = ac3_shift_int32_c;
 
     if (HAVE_MMX)
         ff_ac3dsp_init_x86(c);
diff --git a/libavcodec/ac3dsp.h b/libavcodec/ac3dsp.h
index 62351e9..a4f141f 100644
--- a/libavcodec/ac3dsp.h
+++ b/libavcodec/ac3dsp.h
@@ -46,28 +46,6 @@ 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, int len, unsigned int shift);
-
-    /**
-     * 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  shift amount (negative = right, positive = left)
-     *               constraints: range [-31,31]
-     */
-    void (*ac3_shift_int32)(int32_t *src, int len, int shift);
 } AC3DSPContext;
 
 void ff_ac3dsp_init    (AC3DSPContext *c);
diff --git a/libavcodec/ac3enc_fixed.c b/libavcodec/ac3enc_fixed.c
index 0440407..e5853a3 100644
--- a/libavcodec/ac3enc_fixed.c
+++ b/libavcodec/ac3enc_fixed.c
@@ -278,6 +278,44 @@ 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;
+    }
+}
+
+
+/**
+ * Shift each value in an array by a specified amount.
+ * @param src    input array
+ * @param n      number of values in the array
+ * @param shift  shift amount (negative=right, positive=left)
+ */
+static void shift_int32(int32_t *src, int n, int shift)
+{
+    int i;
+
+    if (shift > 0) {
+        for (i = 0; i < n; i++)
+            src[i] <<= shift;
+    } else if (shift < 0) {
+        shift = -shift;
+        for (i = 0; i < n; i++)
+            src[i] >>= shift;
+    }
+}
+
+
+/**
  * Normalize the input samples to use the maximum available precision.
  * This assumes signed 16-bit input samples.
  *
@@ -286,7 +324,7 @@ static int log2_tab(AC3EncodeContext *s, int16_t *src, int len)
 static int normalize_samples(AC3EncodeContext *s)
 {
     int v = 14 - log2_tab(s, s->windowed_samples, AC3_WINDOW_SIZE);
-    s->ac3dsp.ac3_lshift_int16(s->windowed_samples, AC3_WINDOW_SIZE, v);
+    lshift_tab(s->windowed_samples, AC3_WINDOW_SIZE, v);
     return 9 - v;
 }
 
@@ -301,8 +339,8 @@ 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++) {
-            s->ac3dsp.ac3_shift_int32(block->mdct_coef[ch], AC3_MAX_COEFS,
-                                      block->coeff_shift[ch]);
+            shift_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 a7ec6cb..b1eeca9 100644
--- a/libavcodec/x86/ac3dsp.asm
+++ b/libavcodec/x86/ac3dsp.asm
@@ -133,77 +133,3 @@ 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_shift_int32()
-;-----------------------------------------------------------------------------
-
-%macro AC3_SHIFT_4MM 3 ; src/dst, shift instruction, shift amount
-    mova  m1, [%1         ]
-    mova  m2, [%1+mmsize  ]
-    mova  m3, [%1+mmsize*2]
-    mova  m4, [%1+mmsize*3]
-    %2    m1, %3
-    %2    m2, %3
-    %2    m3, %3
-    %2    m4, %3
-    mova  [%1         ], m1
-    mova  [%1+mmsize  ], m2
-    mova  [%1+mmsize*2], m3
-    mova  [%1+mmsize*3], m4
-    add   %1, mmsize*4
-%endmacro
-
-;-----------------------------------------------------------------------------
-; void ff_ac3_lshift_int16(int16_t *src, int len, unsigned int shift)
-;-----------------------------------------------------------------------------
-
-%macro AC3_LSHIFT_INT16 1
-cglobal ac3_lshift_int16_%1, 3,3,5, src, len, shift
-    test   shiftd, shiftd
-    jz .end
-    movd       m0, shiftd
-    ALIGN 8
-.loop:
-    AC3_SHIFT_4MM srcq, psllw, m0
-    sub      lend, mmsize*2
-    ja .loop
-.end:
-    REP_RET
-%endmacro
-
-INIT_MMX
-AC3_LSHIFT_INT16 mmx
-INIT_XMM
-AC3_LSHIFT_INT16 sse2
-
-;-----------------------------------------------------------------------------
-; void ff_ac3_shift_int32(int32_t *src, int len, int shift)
-;-----------------------------------------------------------------------------
-
-%macro AC3_SHIFT_INT32 1
-cglobal ac3_shift_int32_%1, 3,3,5, src, len, shift
-    test   shiftd, shiftd
-    je .end
-    js .shift_right
-    movd       m0, shiftd
-.loop_left:
-    AC3_SHIFT_4MM srcq, pslld, m0
-    sub      lend, mmsize
-    ja .loop_left
-    jmp .end
-.shift_right:
-    neg    shiftd
-    movd       m0, shiftd
-.loop_right:
-    AC3_SHIFT_4MM srcq, psrad, m0
-    sub      lend, mmsize
-    ja .loop_right
-.end:
-    REP_RET
-%endmacro
-
-INIT_MMX
-AC3_SHIFT_INT32 mmx
-INIT_XMM
-AC3_SHIFT_INT32 sse2
diff --git a/libavcodec/x86/ac3dsp_mmx.c b/libavcodec/x86/ac3dsp_mmx.c
index 7560d34..d8af59c 100644
--- a/libavcodec/x86/ac3dsp_mmx.c
+++ b/libavcodec/x86/ac3dsp_mmx.c
@@ -32,12 +32,6 @@ 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, int len, unsigned int lshift);
-extern void ff_ac3_lshift_int16_sse2(int16_t *src, int len, unsigned int lshift);
-
-extern void ff_ac3_shift_int32_mmx (int32_t *src, int len, int shift);
-extern void ff_ac3_shift_int32_sse2(int32_t *src, int len, int shift);
-
 av_cold void ff_ac3dsp_init_x86(AC3DSPContext *c)
 {
     int mm_flags = av_get_cpu_flags();
@@ -46,8 +40,6 @@ 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_shift_int32  = ff_ac3_shift_int32_mmx;
     }
     if (mm_flags & AV_CPU_FLAG_MMX2 && HAVE_MMX2) {
         c->ac3_exponent_min = ff_ac3_exponent_min_mmxext;
@@ -56,11 +48,6 @@ 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_shift_int32  = ff_ac3_shift_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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