[Mesa-dev] [PATCH] i965: Fix a crash in the texture gradient lowering pass with cube samplers

[Iago Toral Quiroga]

We need to swizzle the rhs to match the number of components in the writemask,
otherwise we'll hit an assertion in ir_assignment.
---
 src/mesa/drivers/dri/i965/brw_lower_texture_gradients.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_lower_texture_gradients.cpp b/src/mesa/drivers/dri/i965/brw_lower_texture_gradients.cpp
index 878a54e..7a5f983 100644
--- a/src/mesa/drivers/dri/i965/brw_lower_texture_gradients.cpp
+++ b/src/mesa/drivers/dri/i965/brw_lower_texture_gradients.cpp
@@ -123,7 +123,9 @@ lower_texture_grad_visitor::visit_leave(ir_texture *ir)
       new(mem_ctx) ir_variable(grad_type, "size", ir_var_temporary);
    if (ir->sampler->type->sampler_dimensionality == GLSL_SAMPLER_DIM_CUBE) {
       base_ir->insert_before(size);
-      base_ir->insert_before(assign(size, expr(ir_unop_i2f, txs), WRITEMASK_XY));
+      base_ir->insert_before(assign(size,
+                                    swizzle_for_size(expr(ir_unop_i2f, txs), 2),
+                                    WRITEMASK_XY));
       base_ir->insert_before(assign(size, new(mem_ctx) ir_constant(1.0f), WRITEMASK_Z));
    } else {
       emit(size, expr(ir_unop_i2f,
-- 
1.9.1