flacenc: Move a scratch buffer to struct used by the function

This avoids allocating/freeing memory at every function call,
checking its return value, and carrying the error around.

libavcodec/flacenc.c

@@ -67,6 +67,7 @@ typedef struct RiceContext {
     enum CodingMode coding_mode;
     int porder;
     int params[MAX_PARTITIONS];
+    uint32_t udata[FLAC_MAX_BLOCKSIZE];
 } RiceContext;
 
 typedef struct FlacSubframe {
@@ -616,7 +617,6 @@ static uint64_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
     uint64_t bits[MAX_PARTITION_ORDER+1];
     int opt_porder;
     RiceContext tmp_rc;
-    uint32_t *udata;
     uint64_t sums[MAX_PARTITION_ORDER + 1][MAX_PARTITIONS] = { { 0 } };
 
     assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER);
@@ -625,11 +625,10 @@ static uint64_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
 
     tmp_rc.coding_mode = rc->coding_mode;
 
-    udata = av_malloc(n * sizeof(uint32_t));
     for (i = 0; i < n; i++)
-        udata[i] = (2*data[i]) ^ (data[i]>>31);
+        rc->udata[i] = (2 * data[i]) ^ (data[i] >> 31);
 
-    calc_sums(pmin, pmax, udata, n, pred_order, sums);
+    calc_sums(pmin, pmax, rc->udata, n, pred_order, sums);
 
     opt_porder = pmin;
     bits[pmin] = UINT32_MAX;
@@ -641,7 +640,6 @@ static uint64_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
         }
     }
 
-    av_freep(&udata);
     return bits[opt_porder];
 }