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//===- MergedLoadStoreMotion.h - merge and hoist/sink load/stores ---------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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//! \file
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//! This pass performs merges of loads and stores on both sides of a
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//  diamond (hammock). It hoists the loads and sinks the stores.
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//
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// The algorithm iteratively hoists two loads to the same address out of a
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// diamond (hammock) and merges them into a single load in the header. Similar
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// it sinks and merges two stores to the tail block (footer). The algorithm
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// iterates over the instructions of one side of the diamond and attempts to
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// find a matching load/store on the other side. It hoists / sinks when it
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// thinks it safe to do so.  This optimization helps with eg. hiding load
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// latencies, triggering if-conversion, and reducing static code size.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_TRANSFORMS_SCALAR_MERGEDLOADSTOREMOTION_H
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#define LLVM_TRANSFORMS_SCALAR_MERGEDLOADSTOREMOTION_H
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#include "llvm/ADT/STLFunctionalExtras.h"
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#include "llvm/IR/PassManager.h"
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namespace llvm {
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class Function;
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struct MergedLoadStoreMotionOptions {
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  bool SplitFooterBB;
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  MergedLoadStoreMotionOptions(bool SplitFooterBB = false)
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      : SplitFooterBB(SplitFooterBB) {}
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  MergedLoadStoreMotionOptions &splitFooterBB(bool SFBB) {
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    SplitFooterBB = SFBB;
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    return *this;
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  }
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};
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class MergedLoadStoreMotionPass
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    : public PassInfoMixin<MergedLoadStoreMotionPass> {
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  MergedLoadStoreMotionOptions Options;
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public:
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  MergedLoadStoreMotionPass()
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      : MergedLoadStoreMotionPass(MergedLoadStoreMotionOptions()) {}
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  MergedLoadStoreMotionPass(const MergedLoadStoreMotionOptions &PassOptions)
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      : Options(PassOptions) {}
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  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
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  void printPipeline(raw_ostream &OS,
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                     function_ref<StringRef(StringRef)> MapClassName2PassName);
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};
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}
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#endif // LLVM_TRANSFORMS_SCALAR_MERGEDLOADSTOREMOTION_H