LLVM  9.0.0svn
InstSimplifyPass.h
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1 //===- InstSimplifyPass.h ---------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 /// \file
9 ///
10 /// Defines passes for running instruction simplification across chunks of IR.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H
15 #define LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H
16 
17 #include "llvm/IR/PassManager.h"
18 
19 namespace llvm {
20 
21 class FunctionPass;
22 
23 /// Run instruction simplification across each instruction in the function.
24 ///
25 /// Instruction simplification has useful constraints in some contexts:
26 /// - It will never introduce *new* instructions.
27 /// - There is no need to iterate to a fixed point.
28 ///
29 /// Many passes use instruction simplification as a library facility, but it may
30 /// also be useful (in tests and other contexts) to have access to this very
31 /// restricted transform at a pass granularity. However, for a much more
32 /// powerful and comprehensive peephole optimization engine, see the
33 /// `instcombine` pass instead.
34 class InstSimplifyPass : public PassInfoMixin<InstSimplifyPass> {
35 public:
37 };
38 
39 /// Create a legacy pass that does instruction simplification on each
40 /// instruction in a function.
42 
43 } // end namespace llvm
44 
45 #endif // LLVM_TRANSFORMS_UTILS_INSTSIMPLIFYPASS_H
This class represents lattice values for constants.
Definition: AllocatorList.h:23
F(f)
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM)
Run instruction simplification across each instruction in the function.
A CRTP mix-in to automatically provide informational APIs needed for passes.
Definition: PassManager.h:365
FunctionPass * createInstSimplifyLegacyPass()
Create a legacy pass that does instruction simplification on each instruction in a function...
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:153
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:284
A container for analyses that lazily runs them and caches their results.
This header defines various interfaces for pass management in LLVM.