git update pixman mesa 13 dec 2011

13 files changed, 196 insertions, 157 deletions

diff --git a/mesalib/src/mesa/SConscript b/mesalib/src/mesa/SConscript
index da4d9b185..bd9e94b82 100644
--- a/mesalib/src/mesa/SConscript
+++ b/mesalib/src/mesa/SConscript
@@ -58,7 +58,6 @@ main_sources = [
     'main/cpuinfo.c',
     'main/debug.c',
     'main/depth.c',
-    'main/depthstencil.c',
     'main/dlist.c',
     'main/dlopen.c',
     'main/drawpix.c',
@@ -162,6 +161,7 @@ swrast_sources = [
     'swrast/s_copypix.c',
     'swrast/s_context.c',
     'swrast/s_depth.c',
+    'swrast/s_depthstencil.c',
     'swrast/s_drawpix.c',
     'swrast/s_feedback.c',
     'swrast/s_fog.c',
diff --git a/mesalib/src/mesa/main/fbobject.c b/mesalib/src/mesa/main/fbobject.c
index 9111caa1b..611a6d0b0 100644
--- a/mesalib/src/mesa/main/fbobject.c
+++ b/mesalib/src/mesa/main/fbobject.c
@@ -2669,8 +2669,10 @@ _mesa_BlitFramebufferEXT(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
    }
 
    if (mask & GL_STENCIL_BUFFER_BIT) {
-      struct gl_renderbuffer *readRb = readFb->_StencilBuffer;
-      struct gl_renderbuffer *drawRb = drawFb->_StencilBuffer;
+      struct gl_renderbuffer *readRb =
+         readFb->Attachment[BUFFER_STENCIL].Renderbuffer;
+      struct gl_renderbuffer *drawRb =
+         drawFb->Attachment[BUFFER_STENCIL].Renderbuffer;
 
       /* From the EXT_framebuffer_object spec:
        *
@@ -2679,7 +2681,6 @@ _mesa_BlitFramebufferEXT(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
        *     ignored."
        */
       if ((readRb == NULL) || (drawRb == NULL)) {
-	 readRb = drawRb = NULL;
 	 mask &= ~GL_STENCIL_BUFFER_BIT;
       }
       else if (_mesa_get_format_bits(readRb->Format, GL_STENCIL_BITS) !=
@@ -2691,8 +2692,10 @@ _mesa_BlitFramebufferEXT(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
    }
 
    if (mask & GL_DEPTH_BUFFER_BIT) {
-      struct gl_renderbuffer *readRb = readFb->_DepthBuffer;
-      struct gl_renderbuffer *drawRb = drawFb->_DepthBuffer;
+      struct gl_renderbuffer *readRb =
+         readFb->Attachment[BUFFER_DEPTH].Renderbuffer;
+      struct gl_renderbuffer *drawRb =
+         drawFb->Attachment[BUFFER_DEPTH].Renderbuffer;
 
       /* From the EXT_framebuffer_object spec:
        *
@@ -2701,7 +2704,6 @@ _mesa_BlitFramebufferEXT(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
        *     ignored."
        */
       if ((readRb == NULL) || (drawRb == NULL)) {
-	 readRb = drawRb = NULL;
 	 mask &= ~GL_DEPTH_BUFFER_BIT;
       }
       else if (_mesa_get_format_bits(readRb->Format, GL_DEPTH_BITS) !=
diff --git a/mesalib/src/mesa/main/framebuffer.c b/mesalib/src/mesa/main/framebuffer.c
index e30f31a39..6d5e4524a 100644
--- a/mesalib/src/mesa/main/framebuffer.c
+++ b/mesalib/src/mesa/main/framebuffer.c
@@ -34,7 +34,6 @@
 #include "imports.h"
 #include "buffers.h"
 #include "context.h"
-#include "depthstencil.h"
 #include "enums.h"
 #include "formats.h"
 #include "macros.h"
@@ -307,24 +306,6 @@ _mesa_resize_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb,
       }
    }
 
-   if (fb->_DepthBuffer) {
-      struct gl_renderbuffer *rb = fb->_DepthBuffer;
-      if (rb->Width != width || rb->Height != height) {
-         if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
-            _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
-         }
-      }
-   }
-
-   if (fb->_StencilBuffer) {
-      struct gl_renderbuffer *rb = fb->_StencilBuffer;
-      if (rb->Width != width || rb->Height != height) {
-         if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
-            _mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
-         }
-      }
-   }
-
    fb->Width = width;
    fb->Height = height;
 
@@ -600,80 +581,6 @@ _mesa_update_framebuffer_visual(struct gl_context *ctx,
 }
 
 
-/**
- * Update the framebuffer's _DepthBuffer field using the renderbuffer
- * found at the given attachment index.
- *
- * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
- * create and install a depth wrapper/adaptor.
- *
- * \param fb  the framebuffer whose _DepthBuffer field to update
- */
-static void
-update_depth_buffer(struct gl_context *ctx, struct gl_framebuffer *fb)
-{
-   struct gl_renderbuffer *depthRb =
-      fb->Attachment[BUFFER_DEPTH].Renderbuffer;
-
-   if (depthRb && _mesa_is_format_packed_depth_stencil(depthRb->Format)) {
-      /* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */
-      if (!fb->_DepthBuffer
-          || fb->_DepthBuffer->Wrapped != depthRb
-          || _mesa_get_format_base_format(fb->_DepthBuffer->Format) != GL_DEPTH_COMPONENT) {
-         /* need to update wrapper */
-         struct gl_renderbuffer *wrapper;
-
-         if (depthRb->Format == MESA_FORMAT_Z32_FLOAT_X24S8) {
-            wrapper = _mesa_new_z32f_renderbuffer_wrapper(ctx, depthRb);
-         }
-         else {
-            wrapper = _mesa_new_z24_renderbuffer_wrapper(ctx, depthRb);
-         }
-         _mesa_reference_renderbuffer(&fb->_DepthBuffer, wrapper);
-         ASSERT(fb->_DepthBuffer->Wrapped == depthRb);
-      }
-   }
-   else {
-      /* depthRb may be null */
-      _mesa_reference_renderbuffer(&fb->_DepthBuffer, depthRb);
-   }
-}
-
-
-/**
- * Update the framebuffer's _StencilBuffer field using the renderbuffer
- * found at the given attachment index.
- *
- * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
- * create and install a stencil wrapper/adaptor.
- *
- * \param fb  the framebuffer whose _StencilBuffer field to update
- */
-static void
-update_stencil_buffer(struct gl_context *ctx, struct gl_framebuffer *fb)
-{
-   struct gl_renderbuffer *stencilRb =
-      fb->Attachment[BUFFER_STENCIL].Renderbuffer;
-
-   if (stencilRb && _mesa_is_format_packed_depth_stencil(stencilRb->Format)) {
-      /* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */
-      if (!fb->_StencilBuffer
-          || fb->_StencilBuffer->Wrapped != stencilRb
-          || _mesa_get_format_base_format(fb->_StencilBuffer->Format) != GL_STENCIL_INDEX) {
-         /* need to update wrapper */
-         struct gl_renderbuffer *wrapper
-            = _mesa_new_s8_renderbuffer_wrapper(ctx, stencilRb);
-         _mesa_reference_renderbuffer(&fb->_StencilBuffer, wrapper);
-         ASSERT(fb->_StencilBuffer->Wrapped == stencilRb);
-      }
-   }
-   else {
-      /* stencilRb may be null */
-      _mesa_reference_renderbuffer(&fb->_StencilBuffer, stencilRb);
-   }
-}
-
-
 /*
  * Example DrawBuffers scenarios:
  *
@@ -812,8 +719,6 @@ update_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
     */
    update_color_draw_buffers(ctx, fb);
    update_color_read_buffer(ctx, fb);
-   update_depth_buffer(ctx, fb);
-   update_stencil_buffer(ctx, fb);
 
    compute_depth_max(fb);
 }
diff --git a/mesalib/src/mesa/main/mtypes.h b/mesalib/src/mesa/main/mtypes.h
index fc494f748..1e06cd55c 100644
--- a/mesalib/src/mesa/main/mtypes.h
+++ b/mesalib/src/mesa/main/mtypes.h
@@ -2650,8 +2650,9 @@ struct gl_framebuffer
    struct gl_renderbuffer *_ColorDrawBuffers[MAX_DRAW_BUFFERS];
    struct gl_renderbuffer *_ColorReadBuffer;
 
-   /** The Actual depth/stencil buffers to use.  May be wrappers around the
-    * depth/stencil buffers attached above. */
+   /** Wrappers to make combined depth/stencil buffers look like separate
+    * buffers.  Only used by swrast.  Will be removed in the future.
+    */
    struct gl_renderbuffer *_DepthBuffer;
    struct gl_renderbuffer *_StencilBuffer;
 
diff --git a/mesalib/src/mesa/sources.mak b/mesalib/src/mesa/sources.mak
index a3ce85535..09cdd261b 100644
--- a/mesalib/src/mesa/sources.mak
+++ b/mesalib/src/mesa/sources.mak
@@ -27,7 +27,6 @@ MAIN_SOURCES = \
 	main/cpuinfo.c \
 	main/debug.c \
 	main/depth.c \
-	main/depthstencil.c \
 	main/dlist.c \
 	main/dlopen.c \
 	main/drawpix.c \
@@ -134,6 +133,7 @@ SWRAST_SOURCES = \
 	swrast/s_copypix.c \
 	swrast/s_context.c \
 	swrast/s_depth.c \
+	swrast/s_depthstencil.c \
 	swrast/s_drawpix.c \
 	swrast/s_feedback.c \
 	swrast/s_fog.c \
diff --git a/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c b/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
index 912241b35..65b444552 100644
--- a/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
+++ b/mesalib/src/mesa/state_tracker/st_cb_drawpixels.c
@@ -1182,12 +1182,9 @@ copy_stencil_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,
       return;
    }
 
-   /* Get the dest renderbuffer.  If there's a wrapper, use the
-    * underlying renderbuffer.
-    */
-   rbDraw = st_renderbuffer(ctx->DrawBuffer->_StencilBuffer);
-   if (rbDraw->Base.Wrapped)
-      rbDraw = st_renderbuffer(rbDraw->Base.Wrapped);
+   /* Get the dest renderbuffer */
+   rbDraw = st_renderbuffer(ctx->DrawBuffer->
+                            Attachment[BUFFER_STENCIL].Renderbuffer);
 
    /* this will do stencil pixel transfer ops */
    _mesa_readpixels(ctx, srcx, srcy, width, height,
@@ -1484,7 +1481,8 @@ st_CopyPixels(struct gl_context *ctx, GLint srcx, GLint srcy,
    }
    else {
       assert(type == GL_DEPTH);
-      rbRead = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
+      rbRead = st_renderbuffer(ctx->ReadBuffer->
+                               Attachment[BUFFER_DEPTH].Renderbuffer);
       color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
 
       fpv = get_depth_stencil_fp_variant(st, GL_TRUE, GL_FALSE);
@@ -1496,10 +1494,6 @@ st_CopyPixels(struct gl_context *ctx, GLint srcx, GLint srcy,
    /* update fragment program constants */
    st_upload_constants(st, fpv->parameters, PIPE_SHADER_FRAGMENT);
 
-
-   if (rbRead->Base.Wrapped)
-      rbRead = st_renderbuffer(rbRead->Base.Wrapped);
-
    sample_count = rbRead->texture->nr_samples;
    /* I believe this would be legal, presumably would need to do a resolve
       for color, and for depth/stencil spec says to just use one of the
diff --git a/mesalib/src/mesa/state_tracker/st_cb_texture.c b/mesalib/src/mesa/state_tracker/st_cb_texture.c
index 52f654d7d..289ad5114 100644
--- a/mesalib/src/mesa/state_tracker/st_cb_texture.c
+++ b/mesalib/src/mesa/state_tracker/st_cb_texture.c
@@ -1385,10 +1385,7 @@ st_copy_texsubimage(struct gl_context *ctx,
    /* determine if copying depth or color data */
    if (texBaseFormat == GL_DEPTH_COMPONENT ||
        texBaseFormat == GL_DEPTH_STENCIL) {
-      strb = st_renderbuffer(fb->_DepthBuffer);
-      if (strb->Base.Wrapped) {
-         strb = st_renderbuffer(strb->Base.Wrapped);
-      }
+      strb = st_renderbuffer(fb->Attachment[BUFFER_DEPTH].Renderbuffer);
    }
    else {
       /* texBaseFormat == GL_RGB, GL_RGBA, GL_ALPHA, etc */
diff --git a/mesalib/src/mesa/swrast/s_blit.c b/mesalib/src/mesa/swrast/s_blit.c
index f094be898..2817ec12f 100644
--- a/mesalib/src/mesa/swrast/s_blit.c
+++ b/mesalib/src/mesa/swrast/s_blit.c
@@ -573,6 +573,9 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
       return;
    }
 
+   if (SWRAST_CONTEXT(ctx)->NewState)
+      _swrast_validate_derived(ctx);
+
    swrast_render_start(ctx);
 
    if (srcX1 - srcX0 == dstX1 - dstX0 &&
diff --git a/mesalib/src/mesa/swrast/s_clear.c b/mesalib/src/mesa/swrast/s_clear.c
index 615747d69..851f6d165 100644
--- a/mesalib/src/mesa/swrast/s_clear.c
+++ b/mesalib/src/mesa/swrast/s_clear.c
@@ -213,6 +213,9 @@ _swrast_Clear(struct gl_context *ctx, GLbitfield buffers)
    if (!_mesa_check_conditional_render(ctx))
       return; /* don't clear */
 
+   if (SWRAST_CONTEXT(ctx)->NewState)
+      _swrast_validate_derived(ctx);
+
    swrast_render_start(ctx);
 
    /* do software clearing here */
diff --git a/mesalib/src/mesa/swrast/s_context.c b/mesalib/src/mesa/swrast/s_context.c
index 924612578..6850a09f3 100644
--- a/mesalib/src/mesa/swrast/s_context.c
+++ b/mesalib/src/mesa/swrast/s_context.c
@@ -36,6 +36,7 @@
 #include "swrast.h"
 #include "s_blend.h"
 #include "s_context.h"
+#include "s_depthstencil.h"
 #include "s_lines.h"
 #include "s_points.h"
 #include "s_span.h"
@@ -545,6 +546,25 @@ _swrast_update_active_attribs(struct gl_context *ctx)
 }
 
 
+/**
+ * Update the depth/stencil renderbuffers, if needed.
+ */
+static void
+_swrast_update_depth_stencil(struct gl_context *ctx)
+{
+   struct gl_framebuffer *drawFb = ctx->DrawBuffer;
+   struct gl_framebuffer *readFb = ctx->ReadBuffer;
+
+   _swrast_update_depth_buffer(ctx, drawFb);
+   _swrast_update_stencil_buffer(ctx, drawFb);
+
+   if (readFb != drawFb) {
+      _swrast_update_depth_buffer(ctx, readFb);
+      _swrast_update_stencil_buffer(ctx, readFb);
+   }
+}
+
+
 void
 _swrast_validate_derived( struct gl_context *ctx )
 {
@@ -589,6 +609,9 @@ _swrast_validate_derived( struct gl_context *ctx )
                               _NEW_TEXTURE))
          _swrast_update_specular_vertex_add(ctx);
 
+      if (swrast->NewState & _NEW_BUFFERS)
+         _swrast_update_depth_stencil(ctx);
+
       swrast->NewState = 0;
       swrast->StateChanges = 0;
       swrast->InvalidateState = _swrast_invalidate_state;
diff --git a/mesalib/src/mesa/main/depthstencil.c b/mesalib/src/mesa/swrast/s_depthstencil.c
index af5c12f67..dc768e216 100644
--- a/mesalib/src/mesa/main/depthstencil.c
+++ b/mesalib/src/mesa/swrast/s_depthstencil.c
@@ -22,13 +22,13 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-#include "glheader.h"
-#include "imports.h"
-#include "context.h"
-#include "formats.h"
-#include "mtypes.h"
-#include "depthstencil.h"
-#include "renderbuffer.h"
+#include "main/glheader.h"
+#include "main/imports.h"
+#include "main/context.h"
+#include "main/formats.h"
+#include "main/mtypes.h"
+#include "main/renderbuffer.h"
+#include "swrast/s_depthstencil.h"
 
 
 /**
@@ -349,9 +349,9 @@ put_mono_values_z24(struct gl_context *ctx, struct gl_renderbuffer *z24rb,
  * a depth renderbuffer.
  * \return new depth renderbuffer
  */
-struct gl_renderbuffer *
-_mesa_new_z24_renderbuffer_wrapper(struct gl_context *ctx,
-                                   struct gl_renderbuffer *dsrb)
+static struct gl_renderbuffer *
+new_z24_renderbuffer_wrapper(struct gl_context *ctx,
+                             struct gl_renderbuffer *dsrb)
 {
    struct gl_renderbuffer *z24rb;
 
@@ -563,9 +563,9 @@ put_mono_values_z32f(struct gl_context *ctx, struct gl_renderbuffer *z32frb,
  * a depth renderbuffer.
  * \return new depth renderbuffer
  */
-struct gl_renderbuffer *
-_mesa_new_z32f_renderbuffer_wrapper(struct gl_context *ctx,
-                                    struct gl_renderbuffer *dsrb)
+static struct gl_renderbuffer *
+new_z32f_renderbuffer_wrapper(struct gl_context *ctx,
+                              struct gl_renderbuffer *dsrb)
 {
    struct gl_renderbuffer *z32frb;
 
@@ -915,8 +915,8 @@ put_mono_values_s8(struct gl_context *ctx, struct gl_renderbuffer *s8rb, GLuint
  * a stencil renderbuffer.
  * \return new stencil renderbuffer
  */
-struct gl_renderbuffer *
-_mesa_new_s8_renderbuffer_wrapper(struct gl_context *ctx, struct gl_renderbuffer *dsrb)
+static struct gl_renderbuffer *
+new_s8_renderbuffer_wrapper(struct gl_context *ctx, struct gl_renderbuffer *dsrb)
 {
    struct gl_renderbuffer *s8rb;
 
@@ -957,3 +957,81 @@ _mesa_new_s8_renderbuffer_wrapper(struct gl_context *ctx, struct gl_renderbuffer
 
    return s8rb;
 }
+
+
+/**
+ * Update the framebuffer's _DepthBuffer field using the renderbuffer
+ * found at the given attachment index.
+ *
+ * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
+ * create and install a depth wrapper/adaptor.
+ *
+ * \param fb  the framebuffer whose _DepthBuffer field to update
+ */
+void
+_swrast_update_depth_buffer(struct gl_context *ctx, struct gl_framebuffer *fb)
+{
+   struct gl_renderbuffer *depthRb =
+      fb->Attachment[BUFFER_DEPTH].Renderbuffer;
+
+   if (depthRb && _mesa_is_format_packed_depth_stencil(depthRb->Format)) {
+      /* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */
+      if (!fb->_DepthBuffer
+          || fb->_DepthBuffer->Wrapped != depthRb
+          || _mesa_get_format_base_format(fb->_DepthBuffer->Format) != GL_DEPTH_COMPONENT) {
+         /* need to update wrapper */
+         struct gl_renderbuffer *wrapper;
+
+         if (depthRb->Format == MESA_FORMAT_Z32_FLOAT_X24S8) {
+            wrapper = new_z32f_renderbuffer_wrapper(ctx, depthRb);
+         }
+         else {
+            wrapper = new_z24_renderbuffer_wrapper(ctx, depthRb);
+         }
+         _mesa_reference_renderbuffer(&fb->_DepthBuffer, wrapper);
+      }
+      ASSERT(fb->_DepthBuffer->Wrapped == depthRb);
+      fb->_DepthBuffer->Width = depthRb->Width;
+      fb->_DepthBuffer->Height = depthRb->Height;
+   }
+   else {
+      /* depthRb may be null */
+      _mesa_reference_renderbuffer(&fb->_DepthBuffer, depthRb);
+   }
+}
+
+
+/**
+ * Update the framebuffer's _StencilBuffer field using the renderbuffer
+ * found at the given attachment index.
+ *
+ * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
+ * create and install a stencil wrapper/adaptor.
+ *
+ * \param fb  the framebuffer whose _StencilBuffer field to update
+ */
+void
+_swrast_update_stencil_buffer(struct gl_context *ctx, struct gl_framebuffer *fb)
+{
+   struct gl_renderbuffer *stencilRb =
+      fb->Attachment[BUFFER_STENCIL].Renderbuffer;
+
+   if (stencilRb && _mesa_is_format_packed_depth_stencil(stencilRb->Format)) {
+      /* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */
+      if (!fb->_StencilBuffer
+          || fb->_StencilBuffer->Wrapped != stencilRb
+          || _mesa_get_format_base_format(fb->_StencilBuffer->Format) != GL_STENCIL_INDEX) {
+         /* need to update wrapper */
+         struct gl_renderbuffer *wrapper
+            = new_s8_renderbuffer_wrapper(ctx, stencilRb);
+         _mesa_reference_renderbuffer(&fb->_StencilBuffer, wrapper);
+      }
+      ASSERT(fb->_StencilBuffer->Wrapped == stencilRb);
+      fb->_StencilBuffer->Width = stencilRb->Width;
+      fb->_StencilBuffer->Height = stencilRb->Height;
+   }
+   else {
+      /* stencilRb may be null */
+      _mesa_reference_renderbuffer(&fb->_StencilBuffer, stencilRb);
+   }
+}
diff --git a/mesalib/src/mesa/main/depthstencil.h b/mesalib/src/mesa/swrast/s_depthstencil.h
index c3871d805..0bf624a7b 100644
--- a/mesalib/src/mesa/main/depthstencil.h
+++ b/mesalib/src/mesa/swrast/s_depthstencil.h
@@ -23,24 +23,17 @@
  */
 
 
-#ifndef DEPTHSTENCIL_H
-#define DEPTHSTENCIL_H
+#ifndef S_DEPTHSTENCIL_H
+#define S_DEPTHSTENCIL_H
 
 struct gl_context;
+struct gl_framebuffer;
 
-extern struct gl_renderbuffer *
-_mesa_new_z24_renderbuffer_wrapper(struct gl_context *ctx,
-                                   struct gl_renderbuffer *dsrb);
+void
+_swrast_update_depth_buffer(struct gl_context *ctx, struct gl_framebuffer *fb);
 
+void
+_swrast_update_stencil_buffer(struct gl_context *ctx, struct gl_framebuffer *fb);
 
-extern struct gl_renderbuffer *
-_mesa_new_z32f_renderbuffer_wrapper(struct gl_context *ctx,
-                                    struct gl_renderbuffer *dsrb);
 
-
-extern struct gl_renderbuffer *
-_mesa_new_s8_renderbuffer_wrapper(struct gl_context *ctx,
-                                  struct gl_renderbuffer *dsrb);
-
-
-#endif /* DEPTHSTENCIL_H */
+#endif /* S_DEPTHSTENCIL_H */
diff --git a/mesalib/src/mesa/swrast/s_renderbuffer.c b/mesalib/src/mesa/swrast/s_renderbuffer.c
index 7622e38fd..bb7cdebfe 100644
--- a/mesalib/src/mesa/swrast/s_renderbuffer.c
+++ b/mesalib/src/mesa/swrast/s_renderbuffer.c
@@ -1888,6 +1888,31 @@ add_stencil_renderbuffer(struct gl_context *ctx, struct gl_framebuffer *fb,
 }
 
 
+static GLboolean
+add_depth_stencil_renderbuffer(struct gl_context *ctx,
+                               struct gl_framebuffer *fb)
+{
+   struct gl_renderbuffer *rb;
+
+   assert(fb->Attachment[BUFFER_DEPTH].Renderbuffer == NULL);
+   assert(fb->Attachment[BUFFER_STENCIL].Renderbuffer == NULL);
+
+   rb = _mesa_new_renderbuffer(ctx, 0);
+   if (!rb) {
+      _mesa_error(ctx, GL_OUT_OF_MEMORY, "Allocating depth+stencil buffer");
+      return GL_FALSE;
+   }
+
+   rb->InternalFormat = GL_DEPTH_STENCIL;
+
+   rb->AllocStorage = soft_renderbuffer_storage;
+   _mesa_add_renderbuffer(fb, BUFFER_DEPTH, rb);
+   _mesa_add_renderbuffer(fb, BUFFER_STENCIL, rb);
+
+   return GL_TRUE;
+}
+
+
 /**
  * Add a software-based accumulation renderbuffer to the given framebuffer.
  * This is a helper routine for device drivers when creating a
@@ -1999,14 +2024,29 @@ _swrast_add_soft_renderbuffers(struct gl_framebuffer *fb,
                               frontRight, backRight);
    }
 
-   if (depth) {
-      assert(fb->Visual.depthBits > 0);
-      add_depth_renderbuffer(NULL, fb, fb->Visual.depthBits);
-   }
+#if 0
+   /* This is pretty much for debugging purposes only since there's a perf
+    * hit for using combined depth/stencil in swrast.
+    */
+   if (depth && fb->Visual.depthBits == 24 &&
+       stencil && fb->Visual.stencilBits == 8) {
+      /* use combined depth/stencil buffer */
+      add_depth_stencil_renderbuffer(NULL, fb);
+   }
+   else
+#else
+   (void) add_depth_stencil_renderbuffer;
+#endif
+   {
+      if (depth) {
+         assert(fb->Visual.depthBits > 0);
+         add_depth_renderbuffer(NULL, fb, fb->Visual.depthBits);
+      }
 
-   if (stencil) {
-      assert(fb->Visual.stencilBits > 0);
-      add_stencil_renderbuffer(NULL, fb, fb->Visual.stencilBits);
+      if (stencil) {
+         assert(fb->Visual.stencilBits > 0);
+         add_stencil_renderbuffer(NULL, fb, fb->Visual.stencilBits);
+      }
    }
 
    if (accum) {