From: Kenneth Graunke <kenneth@whitecape.org>
Date: Wed, 21 Jul 2010 23:57:10 +0000 (-0700)
Subject: ir_constant_expression: Add support for builtins dFdx, dFdy, and fwidth.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=38cb1b273f55f98349d981445cfe06351322b032;p=mesa.git

ir_constant_expression: Add support for builtins dFdx, dFdy, and fwidth.

These always return zero (the derivative of a constant).
---

diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp
index aa53d8d1867..641589ed077 100644
--- a/src/glsl/ir_constant_expression.cpp
+++ b/src/glsl/ir_constant_expression.cpp
@@ -812,7 +812,7 @@ ir_call::constant_expression_value()
    } else if (strcmp(callee, "atan") == 0) {
       return NULL; /* FINISHME: implement this */
    } else if (strcmp(callee, "dFdx") == 0 || strcmp(callee, "dFdy") == 0) {
-      return NULL; /* FINISHME: implement this */
+      return ir_constant::zero(mem_ctx, this->type);
    } else if (strcmp(callee, "ceil") == 0) {
       return NULL; /* FINISHME: implement this */
    } else if (strcmp(callee, "clamp") == 0) {
@@ -842,7 +842,7 @@ ir_call::constant_expression_value()
    } else if (strcmp(callee, "fract") == 0) {
       return NULL; /* FINISHME: implement this */
    } else if (strcmp(callee, "fwidth") == 0) {
-      return NULL; /* FINISHME: implement this */
+      return ir_constant::zero(mem_ctx, this->type);
    } else if (strcmp(callee, "greaterThan") == 0) {
       return NULL; /* FINISHME: implement this */
    } else if (strcmp(callee, "greaterThanEqual") == 0) {