Mesa (glsl2): ir_constant_expression: Add support for ir_unop_sign.

[Ian Romanick]

Module: Mesa
Branch: glsl2
Commit: 14b7b2660c771aa090477c11f85da998ec3d2570
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=14b7b2660c771aa090477c11f85da998ec3d2570

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Thu Jul  8 23:11:14 2010 -0700

ir_constant_expression: Add support for ir_unop_sign.

---

 src/glsl/ir_constant_expression.cpp |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp
index 06d7dd8..5ba6264 100644
--- a/src/glsl/ir_constant_expression.cpp
+++ b/src/glsl/ir_constant_expression.cpp
@@ -262,6 +262,24 @@ ir_constant_visitor::visit(ir_expression *ir)
       }
       break;
 
+   case ir_unop_sign:
+      for (unsigned c = 0; c < ir->operands[0]->type->components(); c++) {
+	 switch (ir->type->base_type) {
+	 case GLSL_TYPE_UINT:
+	    data.u[c] = op[0]->value.i[c] > 0;
+	    break;
+	 case GLSL_TYPE_INT:
+	    data.i[c] = (op[0]->value.i[c] > 0) - (op[0]->value.i[c] < 0);
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    data.f[c] = float((op[0]->value.f[c] > 0)-(op[0]->value.f[c] < 0));
+	    break;
+	 default:
+	    assert(0);
+	 }
+      }
+      break;
+
    case ir_unop_rcp:
       assert(op[0]->type->base_type == GLSL_TYPE_FLOAT);
       for (unsigned c = 0; c < ir->operands[0]->type->components(); c++) {