From 0435cb348aaa8f2d8163a38517a098e27a81adef Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Fri, 27 Aug 2010 12:00:29 -0700 Subject: [PATCH] i965: Fix swizzling in vector splitting for the new FS backend. We weren't smearing a component of a split RHS out to reach an unsplit LHS's writemask, so gl_FragColor (always unsplit) would often get uninitialized values. Fixes: glsl-algebraic-add-add-1 (and probably many others). --- src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp b/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp index d4da86b3b06..00d5c202485 100644 --- a/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp @@ -281,6 +281,9 @@ ir_vector_splitting_visitor::visit_leave(ir_assignment *ir) if (rhs) { new_rhs = new(mem_ctx) ir_dereference_variable(rhs->components[i]); + /* If we're writing into a writemask, smear it out to that channel. */ + if (!lhs) + new_rhs = new(mem_ctx) ir_swizzle(new_rhs, i, i, i, i, i + 1); } else { new_rhs = new(mem_ctx) ir_swizzle(ir->rhs->clone(mem_ctx, NULL), i, i, i, i, 1); -- 2.30.2