LLVM  12.0.0git
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1 //===- SCCP.cpp - Sparse Conditional Constant Propagation -------*- 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 //
9 // \file
10 // This file implements sparse conditional constant propagation and merging:
11 //
12 // Specifically, this:
13 // * Assumes values are constant unless proven otherwise
14 // * Assumes BasicBlocks are dead unless proven otherwise
15 // * Proves values to be constant, and replaces them with constants
16 // * Proves conditional branches to be unconditional
17 //
18 //===----------------------------------------------------------------------===//
23 #include "llvm/ADT/STLExtras.h"
25 #include "llvm/IR/DataLayout.h"
26 #include "llvm/IR/Function.h"
27 #include "llvm/IR/Module.h"
28 #include "llvm/IR/PassManager.h"
31 namespace llvm {
33 class PostDominatorTree;
35 /// This pass performs function-level constant propagation and merging.
36 class SCCPPass : public PassInfoMixin<SCCPPass> {
37 public:
39 };
41 /// Helper struct for bundling up the analysis results per function for IPSCCP.
43  std::unique_ptr<PredicateInfo> PredInfo;
46 };
48 bool runIPSCCP(Module &M, const DataLayout &DL,
49  std::function<const TargetLibraryInfo &(Function &)> GetTLI,
51 } // end namespace llvm
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:111
This class represents lattice values for constants.
Definition: AllocatorList.h:23
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:67
An efficient, type-erasing, non-owning reference to a callable.
Definition: STLExtras.h:176
std::unique_ptr< PredicateInfo > PredInfo
Definition: SCCP.h:43
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM)
Definition: SCCP.cpp:1759
Helper struct for bundling up the analysis results per function for IPSCCP.
Definition: SCCP.h:42
A CRTP mix-in to automatically provide informational APIs needed for passes.
Definition: PassManager.h:374
PostDominatorTree * PDT
Definition: SCCP.h:45
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:151
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:155
This file implements the PredicateInfo analysis, which creates an Extended SSA form for operations us...
bool runIPSCCP(Module &M, const DataLayout &DL, std::function< const TargetLibraryInfo &(Function &)> GetTLI, function_ref< AnalysisResultsForFn(Function &)> getAnalysis)
Definition: SCCP.cpp:1933
Module.h This file contains the declarations for the Module class.
Provides information about what library functions are available for the current target.
PostDominatorTree Class - Concrete subclass of DominatorTree that is used to compute the post-dominat...
DominatorTree * DT
Definition: SCCP.h:44
print Print MemDeps of function
A container for analyses that lazily runs them and caches their results.
This pass performs function-level constant propagation and merging.
Definition: SCCP.h:36
This header defines various interfaces for pass management in LLVM.
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL