cell: Don't segfault when unbinding alpha / stencil / depth test state

3 files changed, 29 insertions, 13 deletions

diff --git a/src/gallium/drivers/cell/ppu/cell_pipe_state.c b/src/gallium/drivers/cell/ppu/cell_pipe_state.c
index 66ede99d13..c880760e4b 100644
--- a/src/gallium/drivers/cell/ppu/cell_pipe_state.c
+++ b/src/gallium/drivers/cell/ppu/cell_pipe_state.c
@@ -116,7 +116,7 @@ cell_bind_depth_stencil_alpha_state(struct pipe_context *pipe,
 
    draw_flush(cell->draw);
 
-   if (cdsa->code.store == NULL) {
+   if ((cdsa != NULL) && (cdsa->code.store == NULL)) {
       cell_generate_depth_stencil_test(cdsa);
    }
 
diff --git a/src/gallium/drivers/cell/ppu/cell_state_emit.c b/src/gallium/drivers/cell/ppu/cell_state_emit.c
index c8d5fdf709..e2cc9de48a 100644
--- a/src/gallium/drivers/cell/ppu/cell_state_emit.c
+++ b/src/gallium/drivers/cell/ppu/cell_state_emit.c
@@ -74,11 +74,18 @@ cell_emit_state(struct cell_context *cell)
       struct cell_command_depth_stencil_alpha_test dsat;
       
 
-      dsat.base = (intptr_t) cell->depth_stencil->code.store;
-      dsat.size = (char *) cell->depth_stencil->code.csr
-	  - (char *) cell->depth_stencil->code.store;
-      dsat.read_depth = TRUE;
-      dsat.read_stencil = FALSE;
+      if (cell->depth_stencil != NULL) {
+	 dsat.base = (intptr_t) cell->depth_stencil->code.store;
+	 dsat.size = (char *) cell->depth_stencil->code.csr
+	     - (char *) cell->depth_stencil->code.store;
+	 dsat.read_depth = TRUE;
+	 dsat.read_stencil = FALSE;
+      } else {
+	 dsat.base = 0;
+	 dsat.size = 0;
+	 dsat.read_depth = FALSE;
+	 dsat.read_stencil = FALSE;
+      }
 
       {
 	 uint32_t *p = cell->depth_stencil->code.store;
diff --git a/src/gallium/drivers/cell/spu/spu_main.c b/src/gallium/drivers/cell/spu/spu_main.c
index 8e46f6e471..b8bb8e9449 100644
--- a/src/gallium/drivers/cell/spu/spu_main.c
+++ b/src/gallium/drivers/cell/spu/spu_main.c
@@ -260,13 +260,22 @@ cmd_state_depth_stencil(const struct cell_command_depth_stencil_alpha_test *stat
 
    ASSERT_ALIGN16(state->base);
 
-   mfc_get(depth_stencil_code_buffer,
-	   (unsigned int) state->base,  /* src */
-	   ROUNDUP16(state->size),
-	   TAG_BATCH_BUFFER,
-	   0, /* tid */
-	   0  /* rid */);
-   wait_on_mask(1 << TAG_BATCH_BUFFER);
+   if (state->size != 0) {
+      mfc_get(depth_stencil_code_buffer,
+	      (unsigned int) state->base,  /* src */
+	      ROUNDUP16(state->size),
+	      TAG_BATCH_BUFFER,
+	      0, /* tid */
+	      0  /* rid */);
+      wait_on_mask(1 << TAG_BATCH_BUFFER);
+   } else {
+      /* If there is no code, emit a return instruction.
+       */
+      depth_stencil_code_buffer[0] = 0x35;
+      depth_stencil_code_buffer[1] = 0x00;
+      depth_stencil_code_buffer[2] = 0x00;
+      depth_stencil_code_buffer[3] = 0x00;
+   }
 
    spu.frag_test = (frag_test_func) depth_stencil_code_buffer;
    spu.read_depth = state->read_depth;