Mesa (glsl2): ir_to_mesa: Fix EmitCondCodes for boolean vars as condition.

[Eric Anholt]

Module: Mesa
Branch: glsl2
Commit: cbe52c8012659abe5d81cf1180659820e704d290
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=cbe52c8012659abe5d81cf1180659820e704d290

Author: Eric Anholt <eric at anholt.net>
Date:   Mon Jun 28 12:16:03 2010 -0700

ir_to_mesa: Fix EmitCondCodes for boolean vars as condition.

Fixes glsl-vs-if-bool.

---

 src/mesa/shader/ir_to_mesa.cpp |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/src/mesa/shader/ir_to_mesa.cpp b/src/mesa/shader/ir_to_mesa.cpp
index 3141a53..85aedd6 100644
--- a/src/mesa/shader/ir_to_mesa.cpp
+++ b/src/mesa/shader/ir_to_mesa.cpp
@@ -1146,12 +1146,26 @@ void
 ir_to_mesa_visitor::visit(ir_if *ir)
 {
    ir_to_mesa_instruction *cond_inst, *if_inst, *else_inst = NULL;
+   ir_to_mesa_instruction *prev_inst;
+
+   prev_inst = (ir_to_mesa_instruction *)this->instructions.get_tail();
 
    ir->condition->accept(this);
    assert(this->result.file != PROGRAM_UNDEFINED);
 
    if (ctx->Shader.EmitCondCodes) {
       cond_inst = (ir_to_mesa_instruction *)this->instructions.get_tail();
+
+      /* See if we actually generated any instruction for generating
+       * the condition.  If not, then cook up a move to a temp so we
+       * have something to set cond_update on.
+       */
+      if (cond_inst == prev_inst) {
+	 ir_to_mesa_src_reg temp = get_temp(glsl_type::bool_type);
+	 cond_inst = ir_to_mesa_emit_op1(ir->condition, OPCODE_MOV,
+					 ir_to_mesa_dst_reg_from_src(temp),
+					 result);
+      }
       cond_inst->cond_update = GL_TRUE;
 
       if_inst = ir_to_mesa_emit_op1(ir->condition,