Enable needed extensions in generated GLSL shaders and call them when possible.
reland: use the defined preprocessor function.
BUG=angleproject:1044
Change-Id: I6171708a2d55ec085ba2c598a1a863779842da6c
Reviewed-on: https://chromium-review.googlesource.com/311270
Tryjob-Request: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/compiler/translator/ExtensionGLSL.cpp b/src/compiler/translator/ExtensionGLSL.cpp
new file mode 100644
index 0000000..d7f45f7
--- /dev/null
+++ b/src/compiler/translator/ExtensionGLSL.cpp
@@ -0,0 +1,100 @@
+//
+// Copyright (c) 2015 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.
+//
+// ExtensionGLSL.cpp: Implements the TExtensionGLSL class that tracks GLSL extension requirements
+// of shaders.
+
+#include "compiler/translator/ExtensionGLSL.h"
+
+#include "compiler/translator/VersionGLSL.h"
+
+TExtensionGLSL::TExtensionGLSL(ShShaderOutput output)
+ : TIntermTraverser(true, false, false), mTargetVersion(ShaderOutputTypeToGLSLVersion(output))
+{
+}
+
+const std::set<std::string> &TExtensionGLSL::getEnabledExtensions() const
+{
+ return mEnabledExtensions;
+}
+
+const std::set<std::string> &TExtensionGLSL::getRequiredExtensions() const
+{
+ return mRequiredExtensions;
+}
+
+bool TExtensionGLSL::visitUnary(Visit, TIntermUnary *node)
+{
+ checkOperator(node);
+
+ return true;
+}
+
+bool TExtensionGLSL::visitAggregate(Visit, TIntermAggregate *node)
+{
+ checkOperator(node);
+
+ return true;
+}
+
+void TExtensionGLSL::checkOperator(TIntermOperator *node)
+{
+ if (mTargetVersion < GLSL_VERSION_130)
+ {
+ return;
+ }
+
+ switch (node->getOp())
+ {
+ case EOpAbs:
+ break;
+
+ case EOpSign:
+ break;
+
+ case EOpMix:
+ break;
+
+ case EOpFloatBitsToInt:
+ case EOpFloatBitsToUint:
+ case EOpIntBitsToFloat:
+ case EOpUintBitsToFloat:
+ if (mTargetVersion < GLSL_VERSION_330)
+ {
+ // Bit conversion functions cannot be emulated.
+ mRequiredExtensions.insert("GL_ARB_shader_bit_encoding");
+ }
+ break;
+
+ case EOpPackSnorm2x16:
+ case EOpPackHalf2x16:
+ case EOpUnpackSnorm2x16:
+ case EOpUnpackHalf2x16:
+ if (mTargetVersion < GLSL_VERSION_420)
+ {
+ mEnabledExtensions.insert("GL_ARB_shading_language_packing");
+
+ if (mTargetVersion < GLSL_VERSION_330)
+ {
+ // floatBitsToUint and uintBitsToFloat are needed to emulate
+ // packHalf2x16 and unpackHalf2x16 respectively and cannot be
+ // emulated themselves.
+ mRequiredExtensions.insert("GL_ARB_shader_bit_encoding");
+ }
+ }
+ break;
+
+ case EOpPackUnorm2x16:
+ case EOpUnpackUnorm2x16:
+ if (mTargetVersion < GLSL_VERSION_410)
+ {
+ mEnabledExtensions.insert("GL_ARB_shading_language_packing");
+ }
+ break;
+
+ default:
+ break;
+ }
+}