Support array initialization in HLSL output

src/compiler.gypi

@@ -153,6 +153,8 @@
             'compiler/translator/RemoveSwitchFallThrough.h',
             'compiler/translator/RewriteElseBlocks.cpp',
             'compiler/translator/RewriteElseBlocks.h',
+            'compiler/translator/SeparateArrayInitialization.cpp',
+            'compiler/translator/SeparateArrayInitialization.h',
             'compiler/translator/SeparateDeclarations.cpp',
             'compiler/translator/SeparateDeclarations.h',
             'compiler/translator/SimplifyArrayAssignment.cpp',

src/compiler/translator/SeparateArrayInitialization.cpp

+//
+// 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.
+//
+// The SeparateArrayInitialization function splits each array initialization into a declaration and an assignment.
+// Example:
+//     type[n] a = initializer;
+// will effectively become
+//     type[n] a;
+//     a = initializer;
+
+#include "compiler/translator/SeparateArrayInitialization.h"
+
+#include "compiler/translator/IntermNode.h"
+
+namespace
+{
+
+class SeparateArrayInitTraverser : private TIntermTraverser
+{
+  public:
+    static void apply(TIntermNode *root);
+  private:
+    SeparateArrayInitTraverser();
+    bool visitAggregate(Visit, TIntermAggregate *node) override;
+};
+
+void SeparateArrayInitTraverser::apply(TIntermNode *root)
+{
+    SeparateArrayInitTraverser separateInit;
+    root->traverse(&separateInit);
+    separateInit.updateTree();
+}
+
+SeparateArrayInitTraverser::SeparateArrayInitTraverser()
+    : TIntermTraverser(true, false, false)
+{
+}
+
+bool SeparateArrayInitTraverser::visitAggregate(Visit, TIntermAggregate *node)
+{
+    if (node->getOp() == EOpDeclaration)
+    {
+        TIntermSequence *sequence = node->getSequence();
+        TIntermBinary *initNode = sequence->back()->getAsBinaryNode();
+        if (initNode != nullptr && initNode->getOp() == EOpInitialize)
+        {
+            TIntermTyped *initializer = initNode->getRight();
+            if (initializer->isArray())
+            {
+                // We rely on that array declarations have been isolated to single declarations.
+                ASSERT(sequence->size() == 1);
+                TIntermTyped *symbol = initNode->getLeft();
+                TIntermAggregate *parentAgg = getParentNode()->getAsAggregate();
+                ASSERT(parentAgg != nullptr);
+
+                TIntermSequence replacements;
+
+                TIntermAggregate *replacementDeclaration = new TIntermAggregate;
+                replacementDeclaration->setOp(EOpDeclaration);
+                replacementDeclaration->getSequence()->push_back(symbol);
+                replacementDeclaration->setLine(symbol->getLine());
+                replacements.push_back(replacementDeclaration);
+
+                TIntermBinary *replacementAssignment = new TIntermBinary(EOpAssign);
+                replacementAssignment->setLeft(symbol);
+                replacementAssignment->setRight(initializer);
+                replacementAssignment->setType(initializer->getType());
+                replacementAssignment->setLine(symbol->getLine());
+                replacements.push_back(replacementAssignment);
+
+                mMultiReplacements.push_back(NodeReplaceWithMultipleEntry(parentAgg, node, replacements));
+            }
+        }
+        return false;
+    }
+    return true;
+}
+
+} // namespace
+
+void SeparateArrayInitialization(TIntermNode *root)
+{
+    SeparateArrayInitTraverser::apply(root);
+}

src/compiler/translator/SeparateArrayInitialization.h

+//
+// 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.
+//
+// The SeparateArrayInitialization function splits each array initialization into a declaration and an assignment.
+// Example:
+//     type[n] a = initializer;
+// will effectively become
+//     type[n] a;
+//     a = initializer;
+
+#ifndef COMPILER_TRANSLATOR_SEPARATEARRAYINITIALIZATION_H_
+#define COMPILER_TRANSLATOR_SEPARATEARRAYINITIALIZATION_H_
+
+class TIntermNode;
+
+void SeparateArrayInitialization(TIntermNode *root);
+
+#endif  // COMPILER_TRANSLATOR_SEPARATEARRAYINITIALIZATION_H_

src/compiler/translator/TranslatorHLSL.cpp

@@ -7,6 +7,7 @@
 #include "compiler/translator/TranslatorHLSL.h"
 
 #include "compiler/translator/OutputHLSL.h"
+#include "compiler/translator/SeparateArrayInitialization.h"
 #include "compiler/translator/SeparateDeclarations.h"
 #include "compiler/translator/SimplifyArrayAssignment.h"
 
@@ -22,6 +23,9 @@ void TranslatorHLSL::translate(TIntermNode *root, int compileOptions)
 
     SeparateArrayDeclarations(root);
 
+    // Note that SeparateDeclarations needs to be run before SeparateArrayInitialization.
+    SeparateArrayInitialization(root);
+
     SimplifyArrayAssignment simplify;
     root->traverse(&simplify);