Mesa (master): i965: Fix vector splitting RHS channel selection with sparse writemasks.

[Eric Anholt]

Module: Mesa
Branch: master
Commit: 3610e0c1a0edc87cef32b7d5d3f4d9004e31f6c4
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=3610e0c1a0edc87cef32b7d5d3f4d9004e31f6c4

Author: Eric Anholt <eric at anholt.net>
Date:   Mon Sep 27 18:29:15 2010 -0700

i965: Fix vector splitting RHS channel selection with sparse writemasks.

Fixes:
glsl-fs-all-02
glsl-fs-dot-vec2

---

 .../drivers/dri/i965/brw_fs_vector_splitting.cpp   |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

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 83b4af0..552254d 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_vector_splitting.cpp
@@ -264,8 +264,10 @@ ir_vector_splitting_visitor::visit_leave(ir_assignment *ir)
    variable_entry *rhs = rhs_deref ? get_splitting_entry(rhs_deref->var) : NULL;
 
    if (lhs_deref && rhs_deref && (lhs || rhs) && !ir->condition) {
+      unsigned int rhs_chan = 0;
+
       /* Straight assignment of vector variables. */
-      for (unsigned int i = 0; i < ir->rhs->type->vector_elements; i++) {
+      for (unsigned int i = 0; i < ir->lhs->type->vector_elements; i++) {
 	 ir_dereference *new_lhs;
 	 ir_rvalue *new_rhs;
 	 void *mem_ctx = lhs ? lhs->mem_ctx : rhs->mem_ctx;
@@ -283,15 +285,18 @@ ir_vector_splitting_visitor::visit_leave(ir_assignment *ir)
 	 }
 
 	 if (rhs) {
-	    new_rhs = new(mem_ctx) ir_dereference_variable(rhs->components[i]);
+	    new_rhs =
+	       new(mem_ctx) ir_dereference_variable(rhs->components[rhs_chan]);
 	 } else {
 	    new_rhs = new(mem_ctx) ir_swizzle(ir->rhs->clone(mem_ctx, NULL),
-					      i, i, i, i, 1);
+					      rhs_chan, 0, 0, 0, 1);
 	 }
 
 	 ir->insert_before(new(mem_ctx) ir_assignment(new_lhs,
 						      new_rhs,
 						      NULL, writemask));
+
+	 rhs_chan++;
       }
       ir->remove();
    } else if (lhs) {