[Mesa-dev] [PATCH 3/3] i965: Handle ir_binop_ubo_load in boolean expression code.

[Kenneth Graunke]

UBO loads can be boolean-valued expressions, too, so we need to handle
them in emit_bool_to_cond_code() and emit_if_gen6().

However, unlike most expressions, it doesn't make sense to evaluate
their operands, then do something with the results.  We just want to
evaluate the UBO load as a whole---which performs the read from
memory---then load the boolean result into the flag register.

Instead of adding code to handle it, we can simply bypass the
ir_expression handling, and fall through to the default code, which will
do exactly that.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83468
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Cc: Ian Romanick <idr at freedesktop.org>
Cc: mesa-stable at lists.freedesktop.org
---
 src/mesa/drivers/dri/i965/brw_fs_visitor.cpp   | 4 ++--
 src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index d7e3120..ff1e716 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -2235,7 +2235,7 @@ fs_visitor::emit_bool_to_cond_code(ir_rvalue *ir)
 {
    ir_expression *expr = ir->as_expression();
 
-   if (!expr) {
+   if (!expr || expr->operation == ir_binop_ubo_load) {
       ir->accept(this);
 
       fs_inst *inst = emit(AND(reg_null_d, this->result, fs_reg(1)));
@@ -2363,7 +2363,7 @@ fs_visitor::emit_if_gen6(ir_if *ir)
 {
    ir_expression *expr = ir->condition->as_expression();
 
-   if (expr) {
+   if (expr && expr->operation != ir_binop_ubo_load) {
       fs_reg op[3];
       fs_inst *inst;
       fs_reg temp;
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 93ea63d..1e823da 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -776,7 +776,7 @@ vec4_visitor::emit_bool_to_cond_code(ir_rvalue *ir,
 
    *predicate = BRW_PREDICATE_NORMAL;
 
-   if (expr) {
+   if (expr && expr->operation != ir_binop_ubo_load) {
       src_reg op[3];
       vec4_instruction *inst;
 
@@ -897,7 +897,7 @@ vec4_visitor::emit_if_gen6(ir_if *ir)
 {
    ir_expression *expr = ir->condition->as_expression();
 
-   if (expr) {
+   if (expr && expr->operation != ir_binop_ubo_load) {
       src_reg op[3];
       dst_reg temp;
 
-- 
2.1.0