LLVM  14.0.0git
ConstantMerge.h
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1 //===- ConstantMerge.h - Merge duplicate global constants -------*- 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 // This file defines the interface to a pass that merges duplicate global
10 // constants together into a single constant that is shared. This is useful
11 // because some passes (ie TraceValues) insert a lot of string constants into
12 // the program, regardless of whether or not an existing string is available.
13 //
14 // Algorithm: ConstantMerge is designed to build up a map of available constants
15 // and eliminate duplicates when it is initialized.
16 //
17 //===----------------------------------------------------------------------===//
18 
19 #ifndef LLVM_TRANSFORMS_IPO_CONSTANTMERGE_H
20 #define LLVM_TRANSFORMS_IPO_CONSTANTMERGE_H
21 
22 #include "llvm/IR/PassManager.h"
23 
24 namespace llvm {
25 
26 class Module;
27 
28 /// A pass that merges duplicate global constants into a single constant.
29 class ConstantMergePass : public PassInfoMixin<ConstantMergePass> {
30 public:
32 };
33 
34 } // end namespace llvm
35 
36 #endif // LLVM_TRANSFORMS_IPO_CONSTANTMERGE_H
llvm::PreservedAnalyses
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:155
llvm
This is an optimization pass for GlobalISel generic memory operations.
Definition: AllocatorList.h:23
M
We currently emits eax Perhaps this is what we really should generate is Is imull three or four cycles eax eax The current instruction priority is based on pattern complexity The former is more complex because it folds a load so the latter will not be emitted Perhaps we should use AddedComplexity to give LEA32r a higher priority We should always try to match LEA first since the LEA matching code does some estimate to determine whether the match is profitable if we care more about code then imull is better It s two bytes shorter than movl leal On a Pentium M
Definition: README.txt:252
llvm::ConstantMergePass::run
PreservedAnalyses run(Module &M, ModuleAnalysisManager &)
Definition: ConstantMerge.cpp:249
llvm::PassInfoMixin
A CRTP mix-in to automatically provide informational APIs needed for passes.
Definition: PassManager.h:374
llvm::Module
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:67
Module
Machine Check Debug Module
Definition: MachineCheckDebugify.cpp:122
PassManager.h
llvm::AnalysisManager
A container for analyses that lazily runs them and caches their results.
Definition: InstructionSimplify.h:44
llvm::ConstantMergePass
A pass that merges duplicate global constants into a single constant.
Definition: ConstantMerge.h:29