1 files changed, 115 insertions, 0 deletions
diff --git a/Source/ThirdParty/ANGLE/src/compiler/VersionGLSL.cpp b/Source/ThirdParty/ANGLE/src/compiler/VersionGLSL.cpp
new file mode 100644
index 000000000..26cee0527
--- /dev/null
+++ b/Source/ThirdParty/ANGLE/src/compiler/VersionGLSL.cpp
@@ -0,0 +1,115 @@
+//
+// Copyright (c) 2002-2010 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#include "compiler/VersionGLSL.h"
+
+static const int GLSL_VERSION_110 = 110;
+static const int GLSL_VERSION_120 = 120;
+
+// We need to scan for three things:
+// 1. "invariant" keyword: This can occur in both - vertex and fragment shaders
+//    but only at the global scope.
+// 2. "gl_PointCoord" built-in variable: This can only occur in fragment shader
+//    but inside any scope.
+// 3. Call to a matrix constructor with another matrix as argument.
+//    (These constructors were reserved in GLSL version 1.10.)
+//
+// If it weren't for (3) then we would only need to scan the global
+// scope of the vertex shader. However, we need to scan the entire
+// shader in both cases.
+//
+// TODO(alokp): The following two cases of invariant decalaration get lost
+// during parsing - they do not get carried over to the intermediate tree.
+// Handle these cases:
+// 1. When a pragma is used to force all output variables to be invariant:
+//    - #pragma STDGL invariant(all)
+// 2. When a previously decalared or built-in variable is marked invariant:
+//    - invariant gl_Position;
+//    - varying vec3 color; invariant color;
+//
+TVersionGLSL::TVersionGLSL(ShShaderType type)
+    : mShaderType(type),
+      mVersion(GLSL_VERSION_110)
+{
+}
+
+void TVersionGLSL::visitSymbol(TIntermSymbol* node)
+{
+    if (node->getSymbol() == "gl_PointCoord")
+        updateVersion(GLSL_VERSION_120);
+}
+
+void TVersionGLSL::visitConstantUnion(TIntermConstantUnion*)
+{
+}
+
+bool TVersionGLSL::visitBinary(Visit, TIntermBinary*)
+{
+    return true;
+}
+
+bool TVersionGLSL::visitUnary(Visit, TIntermUnary*)
+{
+    return true;
+}
+
+bool TVersionGLSL::visitSelection(Visit, TIntermSelection*)
+{
+    return true;
+}
+
+bool TVersionGLSL::visitAggregate(Visit, TIntermAggregate* node)
+{
+    bool visitChildren = true;
+
+    switch (node->getOp()) {
+      case EOpSequence:
+        // We need to visit sequence children to get to global or inner scope.
+        visitChildren = true;
+        break;
+      case EOpDeclaration: {
+        const TIntermSequence& sequence = node->getSequence();
+        TQualifier qualifier = sequence.front()->getAsTyped()->getQualifier();
+        if ((qualifier == EvqInvariantVaryingIn) ||
+            (qualifier == EvqInvariantVaryingOut)) {
+            updateVersion(GLSL_VERSION_120);
+        }
+        break;
+      }
+      case EOpConstructMat2:
+      case EOpConstructMat3:
+      case EOpConstructMat4: {
+        const TIntermSequence& sequence = node->getSequence();
+        if (sequence.size() == 1) {
+          TIntermTyped* typed = sequence.front()->getAsTyped();
+          if (typed && typed->isMatrix()) {
+            updateVersion(GLSL_VERSION_120);
+          }
+        }
+        break;
+      }
+
+      default: break;
+    }
+
+    return visitChildren;
+}
+
+bool TVersionGLSL::visitLoop(Visit, TIntermLoop*)
+{
+    return true;
+}
+
+bool TVersionGLSL::visitBranch(Visit, TIntermBranch*)
+{
+    return true;
+}
+
+void TVersionGLSL::updateVersion(int version)
+{
+    mVersion = std::max(version, mVersion);
+}
+