don't try and outsmart the compiler on constant multplies

diff --git a/src/libFLAC/fixed.c b/src/libFLAC/fixed.c
index 4018735..7506368 100644 (file)
--- a/src/libFLAC/fixed.c
+++ b/src/libFLAC/fixed.c
@@ -154,6 +154,7 @@ void FLAC__fixed_compute_residual(const int32 data[], unsigned data_len, unsigne
 {
        unsigned i;
 
+#if 0
        switch(order) {
                case 0:
                        for(i = 0; i < data_len; i++) {
@@ -186,6 +187,32 @@ void FLAC__fixed_compute_residual(const int32 data[], unsigned data_len, unsigne
                default:
                        assert(0);
        }
+#else
+       switch(order) {
+               case 0:
+                       for(i = 0; i < data_len; i++)
+                               residual[i] = data[i];
+                       break;
+               case 1:
+                       for(i = 0; i < data_len; i++)
+                               residual[i] = data[i] - data[i-1];
+                       break;
+               case 2:
+                       for(i = 0; i < data_len; i++)
+                               residual[i] = data[i] - 2*data[i-1] + data[i-2];
+                       break;
+               case 3:
+                       for(i = 0; i < data_len; i++)
+                               residual[i] = data[i] - 3*data[i-1] + 3*data[i-2] - data[i-3];
+                       break;
+               case 4:
+                       for(i = 0; i < data_len; i++)
+                               residual[i] = data[i] - 4*data[i-1] + 6*data[i-2] - 4*data[i-3] + data[i-4];
+                       break;
+               default:
+                       assert(0);
+       }
+#endif
 }
 
 void FLAC__fixed_restore_signal(const int32 residual[], unsigned data_len, unsigned order, int32 data[])