mesa/main: bail earlier for size == 0 in _mesa_clear_buffer_sub_data

Note that the conversion of the clear data (when data != NULL) can fail due
to an out of memory condition, but it does not check any error conditions
mandated by the spec. Therefore, it is safe to skip when size == 0.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

diff --git a/src/mesa/main/bufferobj.c b/src/mesa/main/bufferobj.c
index 8dedc366ef2b444a763f67277cb729ad0fedf93b..2fcad6501aeb7f1bbedeb1096398a33c78dcfd84 100644 (file)
--- a/src/mesa/main/bufferobj.c
+++ b/src/mesa/main/bufferobj.c
@@ -1868,12 +1868,14 @@ _mesa_clear_buffer_sub_data(struct gl_context *ctx,
       return;
    }
 
+   /* Bail early. Negative size has already been checked. */
+   if (size == 0)
+      return;
+
    if (data == NULL) {
       /* clear to zeros, per the spec */
-      if (size > 0) {
-         ctx->Driver.ClearBufferSubData(ctx, offset, size,
-                                        NULL, clearValueSize, bufObj);
-      }
+      ctx->Driver.ClearBufferSubData(ctx, offset, size,
+                                     NULL, clearValueSize, bufObj);
       return;
    }
 
@@ -1882,10 +1884,8 @@ _mesa_clear_buffer_sub_data(struct gl_context *ctx,
       return;
    }
 
-   if (size > 0) {
-      ctx->Driver.ClearBufferSubData(ctx, offset, size,
-                                     clearValue, clearValueSize, bufObj);
-   }
+   ctx->Driver.ClearBufferSubData(ctx, offset, size,
+                                  clearValue, clearValueSize, bufObj);
 }
 
 void GLAPIENTRY