Further simplifications to comb2pulses() to remove all conditional branches.

1 files changed, 5 insertions, 9 deletions

diff --git a/libcelt/cwrs.c b/libcelt/cwrs.c
index 9680233..c678578 100644
--- a/libcelt/cwrs.c
+++ b/libcelt/cwrs.c
@@ -269,15 +269,12 @@ celt_uint64_t icwrs64(int _n,int _m,const int *_x,const int *_s,
   _x: The combination with elements sorted in ascending order. _x[_m] = -1
   _s: The associated sign bits.*/
 void comb2pulse(int _n,int _m,int * restrict _y,const int *_x,const int *_s){
-  int j;
   int k;
-  int n;
+  const int signs[2]={1,-1};
   CELT_MEMSET(_y, 0, _n);
-  for(k=j=0;k<_m;k+=n){
-     /* _x[_m] = -1 so we won't overflow */
-    for(n=1;_x[k+n]==_x[k];n++);
-    _y[_x[k]]=_s[k]?-n:n;
-  }
+  k=0; do {
+    _y[_x[k]]+=signs[_s[k]];
+  } while (++k<_m);
 }
 
 /*Converts a pulse vector vector _y of length _n into a combination of _m unit
@@ -371,7 +368,7 @@ void decode_pulses(int *_y, int N, int K, ec_dec *dec)
    VARDECL(int, signs);
    SAVE_STACK;
 
-   ALLOC(comb, K+1, int);
+   ALLOC(comb, K, int);
    ALLOC(signs, K, int);
    /* Simple heuristic to figure out whether it fits in 32 bits */
    if((N+4)*(K+4)<250 || (celt_ilog2(N)+1)*K<31)
@@ -380,7 +377,6 @@ void decode_pulses(int *_y, int N, int K, ec_dec *dec)
    } else {
       decode_comb64(N, K, comb, signs, dec);
    }
-   comb[K] = -1;
    comb2pulse(N, K, _y, comb, signs);
    RESTORE_STACK;
 }