1 files changed, 116 insertions, 0 deletions
diff --git a/gfx/angle/src/compiler/translator/ValidateGlobalInitializer.cpp b/gfx/angle/src/compiler/translator/ValidateGlobalInitializer.cpp
new file mode 100755
index 000000000..d5b1b3be4
--- /dev/null
+++ b/gfx/angle/src/compiler/translator/ValidateGlobalInitializer.cpp
@@ -0,0 +1,116 @@
+//
+// Copyright (c) 2002-2015 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.
+//
+
+#include "compiler/translator/ValidateGlobalInitializer.h"
+
+#include "compiler/translator/ParseContext.h"
+
+namespace sh
+{
+
+namespace
+{
+
+class ValidateGlobalInitializerTraverser : public TIntermTraverser
+{
+  public:
+    ValidateGlobalInitializerTraverser(const TParseContext *context);
+
+    void visitSymbol(TIntermSymbol *node) override;
+    bool visitAggregate(Visit visit, TIntermAggregate *node) override;
+    bool visitBinary(Visit visit, TIntermBinary *node) override;
+    bool visitUnary(Visit visit, TIntermUnary *node) override;
+
+    bool isValid() const { return mIsValid; }
+    bool issueWarning() const { return mIssueWarning; }
+
+  private:
+    const TParseContext *mContext;
+    bool mIsValid;
+    bool mIssueWarning;
+};
+
+void ValidateGlobalInitializerTraverser::visitSymbol(TIntermSymbol *node)
+{
+    const TSymbol *sym = mContext->symbolTable.find(node->getSymbol(), mContext->getShaderVersion());
+    if (sym->isVariable())
+    {
+        // ESSL 1.00 section 4.3 (or ESSL 3.00 section 4.3):
+        // Global initializers must be constant expressions.
+        const TVariable *var = static_cast<const TVariable *>(sym);
+        switch (var->getType().getQualifier())
+        {
+          case EvqConst:
+            break;
+          case EvqGlobal:
+          case EvqTemporary:
+          case EvqUniform:
+            // We allow these cases to be compatible with legacy ESSL 1.00 content.
+            // Implement stricter rules for ESSL 3.00 since there's no legacy content to deal with.
+            if (mContext->getShaderVersion() >= 300)
+            {
+                mIsValid = false;
+            }
+            else
+            {
+                mIssueWarning = true;
+            }
+            break;
+          default:
+            mIsValid = false;
+        }
+    }
+}
+
+bool ValidateGlobalInitializerTraverser::visitAggregate(Visit visit, TIntermAggregate *node)
+{
+    // Disallow calls to user-defined functions and texture lookup functions in global variable initializers.
+    // This is done simply by disabling all function calls - built-in math functions don't use EOpFunctionCall.
+    if (node->getOp() == EOpFunctionCall)
+    {
+        mIsValid = false;
+    }
+    return true;
+}
+
+bool ValidateGlobalInitializerTraverser::visitBinary(Visit visit, TIntermBinary *node)
+{
+    if (node->isAssignment())
+    {
+        mIsValid = false;
+    }
+    return true;
+}
+
+bool ValidateGlobalInitializerTraverser::visitUnary(Visit visit, TIntermUnary *node)
+{
+    if (node->isAssignment())
+    {
+        mIsValid = false;
+    }
+    return true;
+}
+
+ValidateGlobalInitializerTraverser::ValidateGlobalInitializerTraverser(const TParseContext *context)
+    : TIntermTraverser(true, false, false),
+      mContext(context),
+      mIsValid(true),
+      mIssueWarning(false)
+{
+}
+
+} // namespace
+
+bool ValidateGlobalInitializer(TIntermTyped *initializer, const TParseContext *context, bool *warning)
+{
+    ValidateGlobalInitializerTraverser validate(context);
+    initializer->traverse(&validate);
+    ASSERT(warning != nullptr);
+    *warning = validate.issueWarning();
+    return validate.isValid();
+}
+
+}  // namespace sh