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Diffstat (limited to 'gnu/llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombineInternal.h')
| -rw-r--r-- | gnu/llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombineInternal.h | 126 |
1 files changed, 0 insertions, 126 deletions
diff --git a/gnu/llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombineInternal.h b/gnu/llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombineInternal.h deleted file mode 100644 index f3c8bde9f8f..00000000000 --- a/gnu/llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombineInternal.h +++ /dev/null @@ -1,126 +0,0 @@ -//===- AggressiveInstCombineInternal.h --------------------------*- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the instruction pattern combiner classes. -// Currently, it handles pattern expressions for: -// * Truncate instruction -// -//===----------------------------------------------------------------------===// - -#ifndef LLVM_LIB_TRANSFORMS_AGGRESSIVEINSTCOMBINE_COMBINEINTERNAL_H -#define LLVM_LIB_TRANSFORMS_AGGRESSIVEINSTCOMBINE_COMBINEINTERNAL_H - -#include "llvm/ADT/MapVector.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/Analysis/AliasAnalysis.h" -#include "llvm/Analysis/BasicAliasAnalysis.h" -#include "llvm/Analysis/ConstantFolding.h" -#include "llvm/Analysis/GlobalsModRef.h" -#include "llvm/Analysis/TargetLibraryInfo.h" -#include "llvm/IR/DataLayout.h" -#include "llvm/Pass.h" -using namespace llvm; - -//===----------------------------------------------------------------------===// -// TruncInstCombine - looks for expression dags dominated by trunc instructions -// and for each eligible dag, it will create a reduced bit-width expression and -// replace the old expression with this new one and remove the old one. -// Eligible expression dag is such that: -// 1. Contains only supported instructions. -// 2. Supported leaves: ZExtInst, SExtInst, TruncInst and Constant value. -// 3. Can be evaluated into type with reduced legal bit-width (or Trunc type). -// 4. All instructions in the dag must not have users outside the dag. -// Only exception is for {ZExt, SExt}Inst with operand type equal to the -// new reduced type chosen in (3). -// -// The motivation for this optimization is that evaluating and expression using -// smaller bit-width is preferable, especially for vectorization where we can -// fit more values in one vectorized instruction. In addition, this optimization -// may decrease the number of cast instructions, but will not increase it. -//===----------------------------------------------------------------------===// - -namespace llvm { - class DataLayout; - class DominatorTree; - class TargetLibraryInfo; - -class TruncInstCombine { - TargetLibraryInfo &TLI; - const DataLayout &DL; - const DominatorTree &DT; - - /// List of all TruncInst instructions to be processed. - SmallVector<TruncInst *, 4> Worklist; - - /// Current processed TruncInst instruction. - TruncInst *CurrentTruncInst; - - /// Information per each instruction in the expression dag. - struct Info { - /// Number of LSBs that are needed to generate a valid expression. - unsigned ValidBitWidth = 0; - /// Minimum number of LSBs needed to generate the ValidBitWidth. - unsigned MinBitWidth = 0; - /// The reduced value generated to replace the old instruction. - Value *NewValue = nullptr; - }; - /// An ordered map representing expression dag post-dominated by current - /// processed TruncInst. It maps each instruction in the dag to its Info - /// structure. The map is ordered such that each instruction appears before - /// all other instructions in the dag that uses it. - MapVector<Instruction *, Info> InstInfoMap; - -public: - TruncInstCombine(TargetLibraryInfo &TLI, const DataLayout &DL, - const DominatorTree &DT) - : TLI(TLI), DL(DL), DT(DT), CurrentTruncInst(nullptr) {} - - /// Perform TruncInst pattern optimization on given function. - bool run(Function &F); - -private: - /// Build expression dag dominated by the /p CurrentTruncInst and append it to - /// the InstInfoMap container. - /// - /// \return true only if succeed to generate an eligible sub expression dag. - bool buildTruncExpressionDag(); - - /// Calculate the minimal allowed bit-width of the chain ending with the - /// currently visited truncate's operand. - /// - /// \return minimum number of bits to which the chain ending with the - /// truncate's operand can be shrunk to. - unsigned getMinBitWidth(); - - /// Build an expression dag dominated by the current processed TruncInst and - /// Check if it is eligible to be reduced to a smaller type. - /// - /// \return the scalar version of the new type to be used for the reduced - /// expression dag, or nullptr if the expression dag is not eligible - /// to be reduced. - Type *getBestTruncatedType(); - - /// Given a \p V value and a \p SclTy scalar type return the generated reduced - /// value of \p V based on the type \p SclTy. - /// - /// \param V value to be reduced. - /// \param SclTy scalar version of new type to reduce to. - /// \return the new reduced value. - Value *getReducedOperand(Value *V, Type *SclTy); - - /// Create a new expression dag using the reduced /p SclTy type and replace - /// the old expression dag with it. Also erase all instructions in the old - /// dag, except those that are still needed outside the dag. - /// - /// \param SclTy scalar version of new type to reduce expression dag into. - void ReduceExpressionDag(Type *SclTy); -}; -} // end namespace llvm. - -#endif |