commit be59c2fb70591b4df0fea23d630bed1f494d8914
author Olli Etuaho <oetuaho@nvidia.com> Mon Mar 07 11:32:34 2016 +0200
committer Commit Bot <commit-bot@chromium.org> Tue Mar 08 13:28:25 2016 +0000
tree fdbc6b9f677a39dce560c34f18fe576ef25203b7
parent 2b3cc8151ddb1e5f2a7ff71aade6ecb45c889cc0

Fix ambiguous function call issues in HLSL output

D3D compiler can't resolve between these overloaded functions:

float4 vec4(float2x2 x0);
float4 vec4(float4 x0);

Include the parameter types in the function name to disambiguate
between overloaded user-defined functions and constructors, like this:

float4 vec4_float2x2(float2x2 x0);
float4 vec4_float4(float4 x0);

This is only done for float2x2 and float4 parameters, other parameter
types like float2x3 vs. float3x2 don't need this.

BUG=angleproject:1099
BUG=angleproject:1030
TEST=angle_end2end_tests,
     dEQP-GLES3.functional.attribute_location.* (10 more tests pass),
     dEQP-GLES2.functional.attribute_location.*

Change-Id: Ief047d41b0adbc238393c3c13cb29771cbb83d58
Reviewed-on: https://chromium-review.googlesource.com/329882
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>

src/compiler/translator/UtilsHLSL.cpp

diff --git a/src/compiler/translator/UtilsHLSL.cpp b/src/compiler/translator/UtilsHLSL.cpp
index 404ccee..53ea73c 100644
--- a/src/compiler/translator/UtilsHLSL.cpp
+++ b/src/compiler/translator/UtilsHLSL.cpp
@@ -435,4 +435,23 @@
     }
     return 0;
 }
+
+TString DisambiguateFunctionName(const TIntermSequence *parameters)
+{
+    TString disambiguatingString;
+    for (auto parameter : *parameters)
+    {
+        const TType &paramType = parameter->getAsTyped()->getType();
+        // Disambiguation is needed for float2x2 and float4 parameters. These are the only parameter
+        // types that HLSL thinks are identical. float2x3 and float3x2 are different types, for
+        // example. Other parameter types are not added to function names to avoid making function
+        // names longer.
+        if (paramType.getObjectSize() == 4 && paramType.getBasicType() == EbtFloat)
+        {
+            disambiguatingString += "_" + TypeString(paramType);
+        }
+    }
+    return disambiguatingString;
 }
+
+}  // namespace sh