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--- a/src/3rdparty/angle/src/compiler/translator/BreakVariableAliasingInInnerLoops.cpp
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@@ -1,107 +0,0 @@
-//
-// 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_util.h"
-#include "compiler/translator/IntermTraverse.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, CreateZeroNode(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