[Mesa-dev] [PATCH] mesa: use single memcpy when strides match

[Bartosz Tomczyk]

v2: fix indentation
---
 src/mesa/main/readpix.c  | 15 ++++++++++-----
 src/mesa/main/texstore.c | 15 +++++++++++----
 2 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/src/mesa/main/readpix.c b/src/mesa/main/readpix.c
index 25823230d6..606d1e58e5 100644
--- a/src/mesa/main/readpix.c
+++ b/src/mesa/main/readpix.c
@@ -220,7 +220,7 @@ readpixels_memcpy(struct gl_context *ctx,
    struct gl_renderbuffer *rb =
          _mesa_get_read_renderbuffer_for_format(ctx, format);
    GLubyte *dst, *map;
-   int dstStride, stride, j, texelBytes;
+   int dstStride, stride, j, texelBytes, bytesPerRow;
 
    /* Fail if memcpy cannot be used. */
    if (!readpixels_can_use_memcpy(ctx, format, type, packing)) {
@@ -239,12 +239,17 @@ readpixels_memcpy(struct gl_context *ctx,
    }
 
    texelBytes = _mesa_get_format_bytes(rb->Format);
+   bytesPerRow = texelBytes * width;
 
    /* memcpy*/
-   for (j = 0; j < height; j++) {
-      memcpy(dst, map, width * texelBytes);
-      dst += dstStride;
-      map += stride;
+   if (dstStride == stride && dstStride == bytesPerRow) {
+      memcpy(dst, map, bytesPerRow * height);
+   } else {
+      for (j = 0; j < height; j++) {
+         memcpy(dst, map, bytesPerRow);
+         dst += dstStride;
+         map += stride;
+      }
    }
 
    ctx->Driver.UnmapRenderbuffer(ctx, rb);
diff --git a/src/mesa/main/texstore.c b/src/mesa/main/texstore.c
index 615ba63362..3314e557c0 100644
--- a/src/mesa/main/texstore.c
+++ b/src/mesa/main/texstore.c
@@ -1360,10 +1360,17 @@ _mesa_store_compressed_texsubimage(struct gl_context *ctx, GLuint dims,
       if (dstMap) {
 
          /* copy rows of blocks */
-         for (i = 0; i < store.CopyRowsPerSlice; i++) {
-            memcpy(dstMap, src, store.CopyBytesPerRow);
-            dstMap += dstRowStride;
-            src += store.TotalBytesPerRow;
+         if (dstRowStride == store.TotalBytesPerRow &&
+             dstRowStride == store.CopyBytesPerRow) {
+            memcpy(dstMap, src, store.CopyBytesPerRow * store.CopyRowsPerSlice);
+            src += store.CopyBytesPerRow * store.CopyRowsPerSlice;
+         }
+         else {
+            for (i = 0; i < store.CopyRowsPerSlice; i++) {
+               memcpy(dstMap, src, store.CopyBytesPerRow);
+               dstMap += dstRowStride;
+               src += store.TotalBytesPerRow;
+            }
          }
 
          ctx->Driver.UnmapTextureImage(ctx, texImage, slice + zoffset);
-- 
2.12.2