[opus] [PATCH 1/2] Revise celt_fir_c() to not pass in argument "mem"

Linfeng Zhang
2016-06-17T21:09:16Z

The "mem" in celt_fir_c() either is contained in the head of input
"x" in
reverse order already, or can be easily attached to the head of "x"
before
calling the function. Removing argument "mem" can eliminate the
redundant buffer
copies inside.
Update celt_fir_sse4_1() accordingly.
---
 celt/celt_decoder.c        | 10 ++++-----
 celt/celt_lpc.c            | 33 +++++++++++-------------------
 celt/celt_lpc.h            |  5 ++---
 celt/x86/celt_lpc_sse.c    | 51 +++++++++-------------------------------------
 celt/x86/celt_lpc_sse.h    | 10 ++++-----
 celt/x86/x86_celt_map.c    |  1 -
 silk/LPC_analysis_filter.c |  6 +-----
 7 files changed, 34 insertions(+), 82 deletions(-)

diff --git a/celt/celt_decoder.c b/celt/celt_decoder.c
index b978bb3..f8433eb 100644
--- a/celt/celt_decoder.c
+++ b/celt/celt_decoder.c
@@ -509,7 +509,7 @@ static void celt_decode_lost(CELTDecoder * OPUS_RESTRICT st,
int N, int LM)
       opus_val16 fade = Q15ONE;
       int pitch_index;
       VARDECL(opus_val32, etmp);
-      VARDECL(opus_val16, exc);
+      VARDECL(opus_val16, _exc);

       if (loss_count == 0)
       {
@@ -520,7 +520,8 @@ static void celt_decode_lost(CELTDecoder * OPUS_RESTRICT st,
int N, int LM)
       }

       ALLOC(etmp, overlap, opus_val32);
-      ALLOC(exc, MAX_PERIOD, opus_val16);
+      ALLOC(_exc, MAX_PERIOD+LPC_ORDER, opus_val16);
+      opus_val16 *exc = _exc+LPC_ORDER;
       window = mode->window;
       c=0; do {
          opus_val16 decay;
@@ -568,15 +569,14 @@ static void celt_decode_lost(CELTDecoder * OPUS_RESTRICT
st, int N, int LM)
          /* Initialize the LPC history with the samples just before the start
             of the region for which we're computing the excitation. */
          {
-            opus_val16 lpc_mem[LPC_ORDER];
             for (i=0;i<LPC_ORDER;i++)
             {
-               lpc_mem[i] +               exc[MAX_PERIOD-exc_length-1-i]
ROUND16(buf[DECODE_BUFFER_SIZE-exc_length-1-i], SIG_SHIFT);
             }
             /* Compute the excitation for exc_length samples before the loss.
*/
             celt_fir(exc+MAX_PERIOD-exc_length, lpc+c*LPC_ORDER,
-                  exc+MAX_PERIOD-exc_length, exc_length, LPC_ORDER, lpc_mem,
st->arch);
+                  exc+MAX_PERIOD-exc_length, exc_length, LPC_ORDER,
st->arch);
          }

          /* Check if the waveform is decaying, and if so how fast.
diff --git a/celt/celt_lpc.c b/celt/celt_lpc.c
index f02145a..80124df 100644
--- a/celt/celt_lpc.c
+++ b/celt/celt_lpc.c
@@ -90,56 +90,47 @@ int          p


 void celt_fir_c(
-         const opus_val16 *_x,
+         const opus_val16 *x,
          const opus_val16 *num,
-         opus_val16 *_y,
+         opus_val16 *y,
          int N,
          int ord,
-         opus_val16 *mem,
          int arch)
 {
    int i,j;
    VARDECL(opus_val16, rnum);
-   VARDECL(opus_val16, x);
    SAVE_STACK;

    ALLOC(rnum, ord, opus_val16);
-   ALLOC(x, N+ord, opus_val16);
    for(i=0;i<ord;i++)
       rnum[i] = num[ord-i-1];
-   for(i=0;i<ord;i++)
-      x[i] = mem[ord-i-1];
-   for (i=0;i<N;i++)
-      x[i+ord]=_x[i];
-   for(i=0;i<ord;i++)
-      mem[i] = _x[N-i-1];
 #ifdef SMALL_FOOTPRINT
    (void)arch;
    for (i=0;i<N;i++)
    {
-      opus_val32 sum = SHL32(EXTEND32(_x[i]), SIG_SHIFT);
+      opus_val32 sum = SHL32(EXTEND32(x[i]), SIG_SHIFT);
       for (j=0;j<ord;j++)
       {
-         sum = MAC16_16(sum,rnum[j],x[i+j]);
+         sum = MAC16_16(sum,rnum[j],x[i+j-ord]);
       }
-      _y[i] = SATURATE16(PSHR32(sum, SIG_SHIFT));
+      y[i] = SATURATE16(PSHR32(sum, SIG_SHIFT));
    }
 #else
    for (i=0;i<N-3;i+=4)
    {
       opus_val32 sum[4]={0,0,0,0};
-      xcorr_kernel(rnum, x+i, sum, ord, arch);
-      _y[i  ] = SATURATE16(ADD32(EXTEND32(_x[i  ]), PSHR32(sum[0],
SIG_SHIFT)));
-      _y[i+1] = SATURATE16(ADD32(EXTEND32(_x[i+1]), PSHR32(sum[1],
SIG_SHIFT)));
-      _y[i+2] = SATURATE16(ADD32(EXTEND32(_x[i+2]), PSHR32(sum[2],
SIG_SHIFT)));
-      _y[i+3] = SATURATE16(ADD32(EXTEND32(_x[i+3]), PSHR32(sum[3],
SIG_SHIFT)));
+      xcorr_kernel(rnum, x+i-ord, sum, ord, arch);
+      y[i  ] = SATURATE16(ADD32(EXTEND32(x[i  ]), PSHR32(sum[0], SIG_SHIFT)));
+      y[i+1] = SATURATE16(ADD32(EXTEND32(x[i+1]), PSHR32(sum[1], SIG_SHIFT)));
+      y[i+2] = SATURATE16(ADD32(EXTEND32(x[i+2]), PSHR32(sum[2], SIG_SHIFT)));
+      y[i+3] = SATURATE16(ADD32(EXTEND32(x[i+3]), PSHR32(sum[3], SIG_SHIFT)));
    }
    for (;i<N;i++)
    {
       opus_val32 sum = 0;
       for (j=0;j<ord;j++)
-         sum = MAC16_16(sum,rnum[j],x[i+j]);
-      _y[i] = SATURATE16(ADD32(EXTEND32(_x[i]), PSHR32(sum, SIG_SHIFT)));
+         sum = MAC16_16(sum,rnum[j],x[i+j-ord]);
+      y[i] = SATURATE16(ADD32(EXTEND32(x[i]), PSHR32(sum, SIG_SHIFT)));
    }
 #endif
    RESTORE_STACK;
diff --git a/celt/celt_lpc.h b/celt/celt_lpc.h
index 323459e..a4c5fd6 100644
--- a/celt/celt_lpc.h
+++ b/celt/celt_lpc.h
@@ -45,12 +45,11 @@ void celt_fir_c(
          opus_val16 *y,
          int N,
          int ord,
-         opus_val16 *mem,
          int arch);

 #if !defined(OVERRIDE_CELT_FIR)
-#define celt_fir(x, num, y, N, ord, mem, arch) \
-    (celt_fir_c(x, num, y, N, ord, mem, arch))
+#define celt_fir(x, num, y, N, ord, arch) \
+    (celt_fir_c(x, num, y, N, ord, arch))
 #endif

 void celt_iir(const opus_val32 *x,
diff --git a/celt/x86/celt_lpc_sse.c b/celt/x86/celt_lpc_sse.c
index 67e5592..12a9b0e 100644
--- a/celt/x86/celt_lpc_sse.c
+++ b/celt/x86/celt_lpc_sse.c
@@ -40,63 +40,32 @@

 #if defined(FIXED_POINT)

-void celt_fir_sse4_1(const opus_val16 *_x,
+void celt_fir_sse4_1(const opus_val16 *x,
          const opus_val16 *num,
-         opus_val16 *_y,
+         opus_val16 *y,
          int N,
          int ord,
-         opus_val16 *mem,
          int arch)
 {
     int i,j;
     VARDECL(opus_val16, rnum);
-    VARDECL(opus_val16, x);

     __m128i vecNoA;
     opus_int32 noA ;
     SAVE_STACK;

    ALLOC(rnum, ord, opus_val16);
-   ALLOC(x, N+ord, opus_val16);
    for(i=0;i<ord;i++)
       rnum[i] = num[ord-i-1];
-   for(i=0;i<ord;i++)
-      x[i] = mem[ord-i-1];
-
-   for (i=0;i<N-7;i+=8)
-   {
-       x[i+ord  ]=_x[i  ];
-       x[i+ord+1]=_x[i+1];
-       x[i+ord+2]=_x[i+2];
-       x[i+ord+3]=_x[i+3];
-       x[i+ord+4]=_x[i+4];
-       x[i+ord+5]=_x[i+5];
-       x[i+ord+6]=_x[i+6];
-       x[i+ord+7]=_x[i+7];
-   }
-
-   for (;i<N-3;i+=4)
-   {
-       x[i+ord  ]=_x[i  ];
-       x[i+ord+1]=_x[i+1];
-       x[i+ord+2]=_x[i+2];
-       x[i+ord+3]=_x[i+3];
-   }
-
-   for (;i<N;i++)
-         x[i+ord]=_x[i];
-
-   for(i=0;i<ord;i++)
-      mem[i] = _x[N-i-1];
 #ifdef SMALL_FOOTPRINT
    for (i=0;i<N;i++)
    {
-      opus_val32 sum = SHL32(EXTEND32(_x[i]), SIG_SHIFT);
+      opus_val32 sum = SHL32(EXTEND32(x[i]), SIG_SHIFT);
       for (j=0;j<ord;j++)
       {
-         sum = MAC16_16(sum,rnum[j],x[i+j]);
+         sum = MAC16_16(sum,rnum[j],x[i+j-ord]);
       }
-      _y[i] = SATURATE16(PSHR32(sum, SIG_SHIFT));
+      y[i] = SATURATE16(PSHR32(sum, SIG_SHIFT));
    }
 #else
    noA = EXTEND32(1) << SIG_SHIFT >> 1;
@@ -107,22 +76,22 @@ void celt_fir_sse4_1(const opus_val16 *_x,
       opus_val32 sums[4] = {0};
       __m128i vecSum, vecX;

-      xcorr_kernel(rnum, x+i, sums, ord, arch);
+      xcorr_kernel(rnum, x+i-ord, sums, ord, arch);

       vecSum = _mm_loadu_si128((__m128i *)sums);
       vecSum = _mm_add_epi32(vecSum, vecNoA);
       vecSum = _mm_srai_epi32(vecSum, SIG_SHIFT);
-      vecX = OP_CVTEPI16_EPI32_M64(_x + i);
+      vecX = OP_CVTEPI16_EPI32_M64(x + i);
       vecSum = _mm_add_epi32(vecSum, vecX);
       vecSum = _mm_packs_epi32(vecSum, vecSum);
-      _mm_storel_epi64((__m128i *)(_y + i), vecSum);
+      _mm_storel_epi64((__m128i *)(y + i), vecSum);
    }
    for (;i<N;i++)
    {
       opus_val32 sum = 0;
       for (j=0;j<ord;j++)
-         sum = MAC16_16(sum, rnum[j], x[i + j]);
-      _y[i] = SATURATE16(ADD32(EXTEND32(_x[i]), PSHR32(sum, SIG_SHIFT)));
+         sum = MAC16_16(sum, rnum[j], x[i+j-ord]);
+      y[i] = SATURATE16(ADD32(EXTEND32(x[i]), PSHR32(sum, SIG_SHIFT)));
    }

 #endif
diff --git a/celt/x86/celt_lpc_sse.h b/celt/x86/celt_lpc_sse.h
index c5ec796..7d1ecf7 100644
--- a/celt/x86/celt_lpc_sse.h
+++ b/celt/x86/celt_lpc_sse.h
@@ -41,12 +41,11 @@ void celt_fir_sse4_1(
          opus_val16 *y,
          int N,
          int ord,
-         opus_val16 *mem,
          int arch);

 #if defined(OPUS_X86_PRESUME_SSE4_1)
-#define celt_fir(x, num, y, N, ord, mem, arch) \
-    ((void)arch, celt_fir_sse4_1(x, num, y, N, ord, mem, arch))
+#define celt_fir(x, num, y, N, ord, arch) \
+    ((void)arch, celt_fir_sse4_1(x, num, y, N, ord, arch))

 #else

@@ -56,11 +55,10 @@ extern void (*const CELT_FIR_IMPL[OPUS_ARCHMASK + 1])(
          opus_val16 *y,
          int N,
          int ord,
-         opus_val16 *mem,
          int arch);

-#  define celt_fir(x, num, y, N, ord, mem, arch) \
-    ((*CELT_FIR_IMPL[(arch) & OPUS_ARCHMASK])(x, num, y, N, ord, mem,
arch))
+#  define celt_fir(x, num, y, N, ord, arch) \
+    ((*CELT_FIR_IMPL[(arch) & OPUS_ARCHMASK])(x, num, y, N, ord, arch))

 #endif
 #endif
diff --git a/celt/x86/x86_celt_map.c b/celt/x86/x86_celt_map.c
index 8e5e449..1331c10 100644
--- a/celt/x86/x86_celt_map.c
+++ b/celt/x86/x86_celt_map.c
@@ -46,7 +46,6 @@ void (*const CELT_FIR_IMPL[OPUS_ARCHMASK + 1])(
          opus_val16       *y,
          int              N,
          int              ord,
-         opus_val16       *mem,
          int              arch
 ) = {
   celt_fir_c,                /* non-sse */
diff --git a/silk/LPC_analysis_filter.c b/silk/LPC_analysis_filter.c
index 2090667..5aeee4c 100644
--- a/silk/LPC_analysis_filter.c
+++ b/silk/LPC_analysis_filter.c
@@ -50,7 +50,6 @@ void silk_LPC_analysis_filter(
 {
     opus_int   j;
 #ifdef FIXED_POINT
-    opus_int16 mem[SILK_MAX_ORDER_LPC];
     opus_int16 num[SILK_MAX_ORDER_LPC];
 #else
     int ix;
@@ -67,10 +66,7 @@ void silk_LPC_analysis_filter(
     for ( j = 0; j < d; j++ ) {
         num[ j ] = -B[ j ];
     }
-    for (j=0;j<d;j++) {
-        mem[ j ] = in[ d - j - 1 ];
-    }
-    celt_fir( in + d, num, out + d, len - d, d, mem, arch );
+    celt_fir( in + d, num, out + d, len - d, d, arch );
     for ( j = 0; j < d; j++ ) {
         out[ j ] = 0;
     }
--
2.8.0.rc3.226.g39d4020