| //===- InstSimplifyPass.h ---------------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| /// \file |
| /// |
| /// Defines passes for running instruction simplification across chunks of IR. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H |
| #define LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H |
| |
| #include "llvm/IR/PassManager.h" |
| |
| namespace llvm { |
| |
| class FunctionPass; |
| |
| /// Run instruction simplification across each instruction in the function. |
| /// |
| /// Instruction simplification has useful constraints in some contexts: |
| /// - It will never introduce *new* instructions. |
| /// - There is no need to iterate to a fixed point. |
| /// |
| /// Many passes use instruction simplification as a library facility, but it may |
| /// also be useful (in tests and other contexts) to have access to this very |
| /// restricted transform at a pass granularity. However, for a much more |
| /// powerful and comprehensive peephole optimization engine, see the |
| /// `instcombine` pass instead. |
| class InstSimplifyPass : public PassInfoMixin<InstSimplifyPass> { |
| public: |
| PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); |
| }; |
| |
| /// Create a legacy pass that does instruction simplification on each |
| /// instruction in a function. |
| FunctionPass *createInstSimplifyLegacyPass(); |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H |