1 files changed, 206 insertions, 0 deletions
diff --git a/src/3rdparty/angle/src/compiler/translator/ArrayReturnValueToOutParameter.cpp b/src/3rdparty/angle/src/compiler/translator/ArrayReturnValueToOutParameter.cpp
new file mode 100644
index 0000000000..510ade84c1
--- /dev/null
+++ b/src/3rdparty/angle/src/compiler/translator/ArrayReturnValueToOutParameter.cpp
@@ -0,0 +1,206 @@
+//
+// 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 ArrayReturnValueToOutParameter function changes return values of an array type to out parameters in
+// function definitions, prototypes, and call sites.
+
+#include "compiler/translator/ArrayReturnValueToOutParameter.h"
+
+#include "compiler/translator/IntermNode.h"
+
+namespace
+{
+
+void CopyAggregateChildren(TIntermAggregate *from, TIntermAggregate *to)
+{
+    const TIntermSequence *fromSequence = from->getSequence();
+    for (size_t ii = 0; ii < fromSequence->size(); ++ii)
+    {
+        to->getSequence()->push_back(fromSequence->at(ii));
+    }
+}
+
+TIntermSymbol *CreateReturnValueSymbol(const TType &type)
+{
+    TIntermSymbol *node = new TIntermSymbol(0, "angle_return", type);
+    node->setInternal(true);
+    return node;
+}
+
+TIntermSymbol *CreateReturnValueOutSymbol(const TType &type)
+{
+    TType outType(type);
+    outType.setQualifier(EvqOut);
+    return CreateReturnValueSymbol(outType);
+}
+
+TIntermAggregate *CreateReplacementCall(TIntermAggregate *originalCall, TIntermTyped *returnValueTarget)
+{
+    TIntermAggregate *replacementCall = new TIntermAggregate(EOpFunctionCall);
+    replacementCall->setType(TType(EbtVoid));
+    replacementCall->setUserDefined();
+    replacementCall->setNameObj(originalCall->getNameObj());
+    replacementCall->setFunctionId(originalCall->getFunctionId());
+    replacementCall->setLine(originalCall->getLine());
+    TIntermSequence *replacementParameters = replacementCall->getSequence();
+    TIntermSequence *originalParameters = originalCall->getSequence();
+    for (auto &param : *originalParameters)
+    {
+        replacementParameters->push_back(param);
+    }
+    replacementParameters->push_back(returnValueTarget);
+    return replacementCall;
+}
+
+class ArrayReturnValueToOutParameterTraverser : private TIntermTraverser
+{
+  public:
+    static void apply(TIntermNode *root, unsigned int *temporaryIndex);
+  private:
+    ArrayReturnValueToOutParameterTraverser();
+
+    bool visitAggregate(Visit visit, TIntermAggregate *node) override;
+    bool visitBranch(Visit visit, TIntermBranch *node) override;
+    bool visitBinary(Visit visit, TIntermBinary *node) override;
+
+    bool mInFunctionWithArrayReturnValue;
+};
+
+void ArrayReturnValueToOutParameterTraverser::apply(TIntermNode *root, unsigned int *temporaryIndex)
+{
+    ArrayReturnValueToOutParameterTraverser arrayReturnValueToOutParam;
+    arrayReturnValueToOutParam.useTemporaryIndex(temporaryIndex);
+    root->traverse(&arrayReturnValueToOutParam);
+    arrayReturnValueToOutParam.updateTree();
+}
+
+ArrayReturnValueToOutParameterTraverser::ArrayReturnValueToOutParameterTraverser()
+    : TIntermTraverser(true, false, true),
+      mInFunctionWithArrayReturnValue(false)
+{
+}
+
+bool ArrayReturnValueToOutParameterTraverser::visitAggregate(Visit visit, TIntermAggregate *node)
+{
+    if (visit == PreVisit)
+    {
+        if (node->isArray())
+        {
+            if (node->getOp() == EOpFunction)
+            {
+                // Replace the parameters child node of the function definition with another node
+                // that has the out parameter added.
+                // Also set the function to return void.
+
+                TIntermAggregate *params = node->getSequence()->front()->getAsAggregate();
+                ASSERT(params != nullptr && params->getOp() == EOpParameters);
+
+                TIntermAggregate *replacementParams = new TIntermAggregate;
+                replacementParams->setOp(EOpParameters);
+                CopyAggregateChildren(params, replacementParams);
+                replacementParams->getSequence()->push_back(CreateReturnValueOutSymbol(node->getType()));
+                replacementParams->setLine(params->getLine());
+
+                mReplacements.push_back(NodeUpdateEntry(node, params, replacementParams, false));
+
+                node->setType(TType(EbtVoid));
+
+                mInFunctionWithArrayReturnValue = true;
+            }
+            else if (node->getOp() == EOpPrototype)
+            {
+                // Replace the whole prototype node with another node that has the out parameter added.
+                TIntermAggregate *replacement = new TIntermAggregate;
+                replacement->setOp(EOpPrototype);
+                CopyAggregateChildren(node, replacement);
+                replacement->getSequence()->push_back(CreateReturnValueOutSymbol(node->getType()));
+                replacement->setUserDefined();
+                replacement->setNameObj(node->getNameObj());
+                replacement->setFunctionId(node->getFunctionId());
+                replacement->setLine(node->getLine());
+                replacement->setType(TType(EbtVoid));
+
+                mReplacements.push_back(NodeUpdateEntry(getParentNode(), node, replacement, false));
+            }
+            else if (node->getOp() == EOpFunctionCall)
+            {
+                // Handle call sites where the returned array is not assigned.
+                // Examples where f() is a function returning an array:
+                // 1. f();
+                // 2. another_array == f();
+                // 3. another_function(f());
+                // 4. return f();
+                // Cases 2 to 4 are already converted to simpler cases by SeparateExpressionsReturningArrays, so we
+                // only need to worry about the case where a function call returning an array forms an expression by
+                // itself.
+                TIntermAggregate *parentAgg = getParentNode()->getAsAggregate();
+                if (parentAgg != nullptr && parentAgg->getOp() == EOpSequence)
+                {
+                    nextTemporaryIndex();
+                    TIntermSequence replacements;
+                    replacements.push_back(createTempDeclaration(node->getType()));
+                    TIntermSymbol *returnSymbol = createTempSymbol(node->getType());
+                    replacements.push_back(CreateReplacementCall(node, returnSymbol));
+                    mMultiReplacements.push_back(NodeReplaceWithMultipleEntry(parentAgg, node, replacements));
+                }
+                return false;
+            }
+        }
+    }
+    else if (visit == PostVisit)
+    {
+        if (node->getOp() == EOpFunction)
+        {
+            mInFunctionWithArrayReturnValue = false;
+        }
+    }
+    return true;
+}
+
+bool ArrayReturnValueToOutParameterTraverser::visitBranch(Visit visit, TIntermBranch *node)
+{
+    if (mInFunctionWithArrayReturnValue && node->getFlowOp() == EOpReturn)
+    {
+        // Instead of returning a value, assign to the out parameter and then return.
+        TIntermSequence replacements;
+
+        TIntermBinary *replacementAssignment = new TIntermBinary(EOpAssign);
+        TIntermTyped *expression = node->getExpression();
+        ASSERT(expression != nullptr);
+        replacementAssignment->setLeft(CreateReturnValueSymbol(expression->getType()));
+        replacementAssignment->setRight(node->getExpression());
+        replacementAssignment->setType(expression->getType());
+        replacementAssignment->setLine(expression->getLine());
+        replacements.push_back(replacementAssignment);
+
+        TIntermBranch *replacementBranch = new TIntermBranch(EOpReturn, nullptr);
+        replacementBranch->setLine(node->getLine());
+        replacements.push_back(replacementBranch);
+
+        mMultiReplacements.push_back(NodeReplaceWithMultipleEntry(getParentNode()->getAsAggregate(), node, replacements));
+    }
+    return false;
+}
+
+bool ArrayReturnValueToOutParameterTraverser::visitBinary(Visit visit, TIntermBinary *node)
+{
+    if (node->getOp() == EOpAssign && node->getLeft()->isArray())
+    {
+        TIntermAggregate *rightAgg = node->getRight()->getAsAggregate();
+        if (rightAgg != nullptr && rightAgg->getOp() == EOpFunctionCall && rightAgg->isUserDefined())
+        {
+            TIntermAggregate *replacementCall = CreateReplacementCall(rightAgg, node->getLeft());
+            mReplacements.push_back(NodeUpdateEntry(getParentNode(), node, replacementCall, false));
+        }
+    }
+    return false;
+}
+
+} // namespace
+
+void ArrayReturnValueToOutParameter(TIntermNode *root, unsigned int *temporaryIndex)
+{
+    ArrayReturnValueToOutParameterTraverser::apply(root, temporaryIndex);
+}