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diff --git a/gfx/angle/src/compiler/translator/BreakVariableAliasingInInnerLoops.cpp b/gfx/angle/src/compiler/translator/BreakVariableAliasingInInnerLoops.cpp
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index 000000000..018e72cd1
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+++ b/gfx/angle/src/compiler/translator/BreakVariableAliasingInInnerLoops.cpp
@@ -0,0 +1,106 @@
+//
+// 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.
+//
+
+// BreakVariableAliasingInInnerLoops.h: To optimize simple assignments, the HLSL compiler frontend
+//      may record a variable as aliasing another. Sometimes the alias information gets garbled
+//      so we work around this issue by breaking the aliasing chain in inner loops.
+
+#include "BreakVariableAliasingInInnerLoops.h"
+
+#include "compiler/translator/IntermNode.h"
+
+// A HLSL compiler developer gave us more details on the root cause and the workaround needed:
+//     The root problem is that if the HLSL compiler is applying aliasing information even on
+//     incomplete simulations (in this case, a single pass). The bug is triggered by an assignment
+//     that comes from a series of assignments, possibly with swizzled or ternary operators with
+//     known conditionals, where the source is before the loop.
+//     So, a workaround is to add a +0 term to variables the first time they are assigned to in
+//     an inner loop (if they are declared in an outside scope, otherwise there is no need).
+//     This will break the aliasing chain.
+
+// For simplicity here we add a +0 to any assignment that is in at least two nested loops. Because
+// the bug only shows up with swizzles, and ternary assignment, whole array or whole structure
+// assignment don't need a workaround.
+
+namespace sh
+{
+
+namespace
+{
+
+class AliasingBreaker : public TIntermTraverser
+{
+  public:
+    AliasingBreaker() : TIntermTraverser(true, false, true) {}
+
+  protected:
+    bool visitBinary(Visit visit, TIntermBinary *binary)
+    {
+        if (visit != PreVisit)
+        {
+            return false;
+        }
+
+        if (mLoopLevel < 2 || !binary->isAssignment())
+        {
+            return true;
+        }
+
+        TIntermTyped *B = binary->getRight();
+        TType type      = B->getType();
+
+        if (!type.isScalar() && !type.isVector() && !type.isMatrix())
+        {
+            return true;
+        }
+
+        if (type.isArray() || IsSampler(type.getBasicType()))
+        {
+            return true;
+        }
+
+        // We have a scalar / vector / matrix assignment with loop depth 2.
+        // Transform it from
+        //    A = B
+        // to
+        //    A = (B + typeof<B>(0));
+
+        TIntermBinary *bPlusZero = new TIntermBinary(EOpAdd, B, TIntermTyped::CreateZero(type));
+        bPlusZero->setLine(B->getLine());
+
+        binary->replaceChildNode(B, bPlusZero);
+
+        return true;
+    }
+
+    bool visitLoop(Visit visit, TIntermLoop *loop)
+    {
+        if (visit == PreVisit)
+        {
+            mLoopLevel++;
+        }
+        else
+        {
+            ASSERT(mLoopLevel > 0);
+            mLoopLevel--;
+        }
+
+        return true;
+    }
+
+  private:
+    int mLoopLevel = 0;
+};
+
+}  // anonymous namespace
+
+void BreakVariableAliasingInInnerLoops(TIntermNode *root)
+{
+    AliasingBreaker breaker;
+    root->traverse(&breaker);
+}
+
+}  // namespace sh