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-rw-r--r--src/3rdparty/angle/src/compiler/translator/RewriteUnaryMinusOperatorInt.cpp112
1 files changed, 112 insertions, 0 deletions
diff --git a/src/3rdparty/angle/src/compiler/translator/RewriteUnaryMinusOperatorInt.cpp b/src/3rdparty/angle/src/compiler/translator/RewriteUnaryMinusOperatorInt.cpp
new file mode 100644
index 0000000000..fe2ef948b4
--- /dev/null
+++ b/src/3rdparty/angle/src/compiler/translator/RewriteUnaryMinusOperatorInt.cpp
@@ -0,0 +1,112 @@
+//
+// Copyright (c) 2016 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.
+//
+// Implementation of evaluating unary integer variable bug workaround.
+// See header for more info.
+
+#include "compiler/translator/RewriteUnaryMinusOperatorInt.h"
+
+#include "compiler/translator/IntermTraverse.h"
+
+namespace sh
+{
+
+namespace
+{
+
+class Traverser : public TIntermTraverser
+{
+ public:
+ static void Apply(TIntermNode *root);
+
+ private:
+ Traverser();
+ bool visitUnary(Visit visit, TIntermUnary *node) override;
+ void nextIteration();
+
+ bool mFound = false;
+};
+
+// static
+void Traverser::Apply(TIntermNode *root)
+{
+ Traverser traverser;
+ do
+ {
+ traverser.nextIteration();
+ root->traverse(&traverser);
+ if (traverser.mFound)
+ {
+ traverser.updateTree();
+ }
+ } while (traverser.mFound);
+}
+
+Traverser::Traverser() : TIntermTraverser(true, false, false)
+{
+}
+
+void Traverser::nextIteration()
+{
+ mFound = false;
+}
+
+bool Traverser::visitUnary(Visit visit, TIntermUnary *node)
+{
+ if (mFound)
+ {
+ return false;
+ }
+
+ // Decide if the current unary operator is unary minus.
+ if (node->getOp() != EOpNegative)
+ {
+ return true;
+ }
+
+ // Decide if the current operand is an integer variable.
+ TIntermTyped *opr = node->getOperand();
+ if (!opr->getType().isScalarInt())
+ {
+ return true;
+ }
+
+ // Potential problem case detected, apply workaround: -(int) -> ~(int) + 1.
+ // ~(int)
+ TIntermUnary *bitwiseNot = new TIntermUnary(EOpBitwiseNot, opr);
+ bitwiseNot->setLine(opr->getLine());
+
+ // Constant 1 (or 1u)
+ TConstantUnion *one = new TConstantUnion();
+ if (opr->getType().getBasicType() == EbtInt)
+ {
+ one->setIConst(1);
+ }
+ else
+ {
+ one->setUConst(1u);
+ }
+ TIntermConstantUnion *oneNode = new TIntermConstantUnion(one, opr->getType());
+ oneNode->getTypePointer()->setQualifier(EvqConst);
+ oneNode->setLine(opr->getLine());
+
+ // ~(int) + 1
+ TIntermBinary *add = new TIntermBinary(EOpAdd, bitwiseNot, oneNode);
+ add->setLine(opr->getLine());
+
+ queueReplacement(add, OriginalNode::IS_DROPPED);
+
+ mFound = true;
+ return false;
+}
+
+} // anonymous namespace
+
+void RewriteUnaryMinusOperatorInt(TIntermNode *root)
+{
+ Traverser::Apply(root);
+}
+
+} // namespace sh \ No newline at end of file