shithub: libvpx

Download patch

ref: 8a1fb4027345c7f36ef02bea969484018ee0693b
parent: 5cc0a364ae9bd3e3ac6248f85283cf0cfa9ab07f
author: Johann <johannkoenig@google.com>
date: Tue Jan 31 10:18:40 EST 2017 

Remove UNINITIALIZED_IS_SAFE

Where clang static analysis or gcc -Wmaybe-uninitialized warns of
uninitialized values, assign 0 to ints, MB_MODE_COUNT to
MB_PREDICTION_MODE, and B_MODE_COUNT to B_PREDICTION_MODE.

Assert that the modes have been changed from the invalid value by
the end of the function.

Change-Id: Ib11e1ffb08f0a6fe4b6c6729dc93b83b1c4b6350


--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -1633,8 +1633,7 @@
   cm->sharpness_level = cpi->oxcf.Sharpness;
 
   if (cm->horiz_scale != NORMAL || cm->vert_scale != NORMAL) {
-    int UNINITIALIZED_IS_SAFE(hr), UNINITIALIZED_IS_SAFE(hs);
-    int UNINITIALIZED_IS_SAFE(vr), UNINITIALIZED_IS_SAFE(vs);
+    int hr, hs, vr, vs;
 
     Scale2Ratio(cm->horiz_scale, &hr, &hs);
     Scale2Ratio(cm->vert_scale, &vr, &vs);
@@ -2504,8 +2503,7 @@
   /* are we resizing the image */
   if (cm->horiz_scale != 0 || cm->vert_scale != 0) {
 #if CONFIG_SPATIAL_RESAMPLING
-    int UNINITIALIZED_IS_SAFE(hr), UNINITIALIZED_IS_SAFE(hs);
-    int UNINITIALIZED_IS_SAFE(vr), UNINITIALIZED_IS_SAFE(vs);
+    int hr, hs, vr, vs;
     int tmp_height;
 
     if (cm->vert_scale == 3) {
@@ -2538,8 +2536,7 @@
    */
   if (cpi->oxcf.allow_spatial_resampling &&
       (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER)) {
-    int UNINITIALIZED_IS_SAFE(hr), UNINITIALIZED_IS_SAFE(hs);
-    int UNINITIALIZED_IS_SAFE(vr), UNINITIALIZED_IS_SAFE(vs);
+    int hr, hs, vr, vs;
     int new_width, new_height;
 
     /* If we are below the resample DOWN watermark then scale down a
--- a/vp8/encoder/pickinter.c
+++ b/vp8/encoder/pickinter.c
@@ -8,6 +8,7 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#include <assert.h>
 #include <limits.h>
 #include "vpx_config.h"
 #include "./vpx_dsp_rtcd.h"
@@ -299,8 +300,8 @@
     MODE_INFO *const mic = xd->mode_info_context;
     const int mis = xd->mode_info_stride;
 
-    B_PREDICTION_MODE UNINITIALIZED_IS_SAFE(best_mode);
-    int UNINITIALIZED_IS_SAFE(r), UNINITIALIZED_IS_SAFE(d);
+    B_PREDICTION_MODE best_mode = B_MODE_COUNT;
+    int r = 0, d = 0;
 
     if (mb->e_mbd.frame_type == KEY_FRAME) {
       const B_PREDICTION_MODE A = above_block_mode(mic, i, mis);
@@ -313,6 +314,7 @@
 
     cost += r;
     distortion += d;
+    assert(best_mode != B_MODE_COUNT);
     mic->bmi[i].as_mode = best_mode;
 
     /* Break out case where we have already exceeded best so far value
@@ -353,7 +355,7 @@
   int Vaverage = 0;
   int diff;
   int pred_error[4] = { 0, 0, 0, 0 }, best_error = INT_MAX;
-  MB_PREDICTION_MODE UNINITIALIZED_IS_SAFE(best_mode);
+  MB_PREDICTION_MODE best_mode = MB_MODE_COUNT;
 
   for (i = 0; i < 8; ++i) {
     uleft_col[i] = x->dst.u_buffer[i * x->dst.uv_stride - 1];
@@ -442,6 +444,7 @@
     }
   }
 
+  assert(best_mode != MB_MODE_COUNT);
   mb->e_mbd.mode_info_context->mbmi.uv_mode = best_mode;
 }
 
--- a/vp8/encoder/rdopt.c
+++ b/vp8/encoder/rdopt.c
@@ -8,6 +8,7 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#include <assert.h>
 #include <stdio.h>
 #include <math.h>
 #include <limits.h>
@@ -608,9 +609,8 @@
   for (i = 0; i < 16; ++i) {
     MODE_INFO *const mic = xd->mode_info_context;
     const int mis = xd->mode_info_stride;
-    B_PREDICTION_MODE UNINITIALIZED_IS_SAFE(best_mode);
-    int UNINITIALIZED_IS_SAFE(r), UNINITIALIZED_IS_SAFE(ry),
-        UNINITIALIZED_IS_SAFE(d);
+    B_PREDICTION_MODE best_mode = B_MODE_COUNT;
+    int r = 0, ry = 0, d = 0;
 
     if (mb->e_mbd.frame_type == KEY_FRAME) {
       const B_PREDICTION_MODE A = above_block_mode(mic, i, mis);
@@ -627,6 +627,7 @@
     distortion += d;
     tot_rate_y += ry;
 
+    assert(best_mode != B_MODE_COUNT);
     mic->bmi[i].as_mode = best_mode;
 
     if (total_rd >= (int64_t)best_rd) break;
@@ -644,7 +645,7 @@
 static int rd_pick_intra16x16mby_mode(MACROBLOCK *x, int *Rate, int *rate_y,
                                       int *Distortion) {
   MB_PREDICTION_MODE mode;
-  MB_PREDICTION_MODE UNINITIALIZED_IS_SAFE(mode_selected);
+  MB_PREDICTION_MODE mode_selected = MB_MODE_COUNT;
   int rate, ratey;
   int distortion;
   int best_rd = INT_MAX;
@@ -674,6 +675,7 @@
     }
   }
 
+  assert(mode_selected != MB_MODE_COUNT);
   xd->mode_info_context->mbmi.mode = mode_selected;
   return best_rd;
 }
@@ -741,9 +743,9 @@
 static void rd_pick_intra_mbuv_mode(MACROBLOCK *x, int *rate,
                                     int *rate_tokenonly, int *distortion) {
   MB_PREDICTION_MODE mode;
-  MB_PREDICTION_MODE UNINITIALIZED_IS_SAFE(mode_selected);
+  MB_PREDICTION_MODE mode_selected = MB_MODE_COUNT;
   int best_rd = INT_MAX;
-  int UNINITIALIZED_IS_SAFE(d), UNINITIALIZED_IS_SAFE(r);
+  int d = 0, r = 0;
   int rate_to;
   MACROBLOCKD *xd = &x->e_mbd;
 
@@ -787,6 +789,7 @@
   *rate = r;
   *distortion = d;
 
+  assert(mode_selected != MB_MODE_COUNT);
   xd->mode_info_context->mbmi.uv_mode = mode_selected;
 }
 
--- a/vpx_ports/mem.h
+++ b/vpx_ports/mem.h
@@ -23,16 +23,6 @@
 #define DECLARE_ALIGNED(n, typ, val) typ val
 #endif
 
-/* Indicates that the usage of the specified variable has been audited to assure
- * that it's safe to use uninitialized. Silences 'may be used uninitialized'
- * warnings on gcc.
- */
-#if defined(__GNUC__) && __GNUC__
-#define UNINITIALIZED_IS_SAFE(x) x = x
-#else
-#define UNINITIALIZED_IS_SAFE(x) x
-#endif
-
 #if HAVE_NEON && defined(_MSC_VER)
 #define __builtin_prefetch(x)
 #endif