LLVM
15.0.0git
lib
Transforms
Scalar
LowerWidenableCondition.cpp
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//===- LowerWidenableCondition.cpp - Lower the guard intrinsic ---------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This pass lowers the llvm.widenable.condition intrinsic to default value
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// which is i1 true.
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//
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//===----------------------------------------------------------------------===//
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#include "
llvm/Transforms/Scalar/LowerWidenableCondition.h
"
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#include "
llvm/ADT/SmallVector.h
"
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#include "
llvm/IR/Function.h
"
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#include "
llvm/IR/InstIterator.h
"
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#include "
llvm/IR/Instructions.h
"
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#include "
llvm/IR/Intrinsics.h
"
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#include "
llvm/IR/Module.h
"
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#include "
llvm/IR/PatternMatch.h
"
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#include "
llvm/InitializePasses.h
"
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#include "
llvm/Pass.h
"
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#include "
llvm/Transforms/Scalar.h
"
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using namespace
llvm
;
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namespace
{
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struct
LowerWidenableConditionLegacyPass :
public
FunctionPass
{
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static
char
ID
;
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LowerWidenableConditionLegacyPass() :
FunctionPass
(
ID
) {
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initializeLowerWidenableConditionLegacyPassPass
(
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*
PassRegistry::getPassRegistry
());
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}
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bool
runOnFunction
(
Function
&
F
)
override
;
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};
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}
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static
bool
lowerWidenableCondition
(
Function
&
F
) {
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// Check if we can cheaply rule out the possibility of not having any work to
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// do.
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auto
*WCDecl =
F
.getParent()->getFunction(
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Intrinsic::getName
(Intrinsic::experimental_widenable_condition));
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if
(!WCDecl || WCDecl->use_empty())
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return
false
;
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using namespace
llvm::PatternMatch
;
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SmallVector<CallInst *, 8>
ToLower;
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// Traverse through the users of WCDecl.
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// This is presumably cheaper than traversing all instructions in the
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// function.
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for
(
auto
*U : WCDecl->users())
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if
(
auto
*CI = dyn_cast<CallInst>(U))
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if
(CI->getFunction() == &
F
)
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ToLower.push_back(CI);
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if
(ToLower.empty())
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return
false
;
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for
(
auto
*CI : ToLower) {
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CI->replaceAllUsesWith(
ConstantInt::getTrue
(CI->getContext()));
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CI->eraseFromParent();
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}
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return
true
;
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}
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bool
LowerWidenableConditionLegacyPass::runOnFunction
(
Function
&
F
) {
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return
lowerWidenableCondition
(
F
);
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}
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char
LowerWidenableConditionLegacyPass::ID
= 0;
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INITIALIZE_PASS
(LowerWidenableConditionLegacyPass,
"lower-widenable-condition"
,
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"Lower the widenable condition to default true value"
,
false
,
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false
)
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Pass
*
llvm
::
createLowerWidenableConditionPass
() {
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return
new
LowerWidenableConditionLegacyPass();
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}
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PreservedAnalyses
LowerWidenableConditionPass::run
(
Function
&
F
,
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FunctionAnalysisManager
&AM) {
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if
(
lowerWidenableCondition
(
F
))
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return
PreservedAnalyses::none
();
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return
PreservedAnalyses::all
();
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}
llvm::PreservedAnalyses
A set of analyses that are preserved following a run of a transformation pass.
Definition:
PassManager.h:152
LowerWidenableCondition.h
llvm
This is an optimization pass for GlobalISel generic memory operations.
Definition:
AddressRanges.h:17
Scalar.h
InstIterator.h
llvm::Function
Definition:
Function.h:60
Pass.h
llvm::SmallVector
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition:
SmallVector.h:1185
llvm::Intrinsic::getName
StringRef getName(ID id)
Return the LLVM name for an intrinsic, such as "llvm.ppc.altivec.lvx".
Definition:
Function.cpp:879
llvm::PreservedAnalyses::none
static PreservedAnalyses none()
Convenience factory function for the empty preserved set.
Definition:
PassManager.h:155
Module.h
INITIALIZE_PASS
INITIALIZE_PASS(LowerWidenableConditionLegacyPass, "lower-widenable-condition", "Lower the widenable condition to default true value", false, false) Pass *llvm
Definition:
LowerWidenableCondition.cpp:73
F
#define F(x, y, z)
Definition:
MD5.cpp:55
llvm::PassRegistry::getPassRegistry
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
Definition:
PassRegistry.cpp:31
Intrinsics.h
PatternMatch.h
llvm::CallingConv::ID
unsigned ID
LLVM IR allows to use arbitrary numbers as calling convention identifiers.
Definition:
CallingConv.h:24
lowerWidenableCondition
static bool lowerWidenableCondition(Function &F)
Definition:
LowerWidenableCondition.cpp:40
runOnFunction
static bool runOnFunction(Function &F, bool PostInlining)
Definition:
EntryExitInstrumenter.cpp:69
llvm::initializeLowerWidenableConditionLegacyPassPass
void initializeLowerWidenableConditionLegacyPassPass(PassRegistry &)
llvm::ConstantInt::getTrue
static ConstantInt * getTrue(LLVMContext &Context)
Definition:
Constants.cpp:867
llvm::PreservedAnalyses::all
static PreservedAnalyses all()
Construct a special preserved set that preserves all passes.
Definition:
PassManager.h:158
Function.h
llvm::LowerWidenableConditionPass::run
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM)
Definition:
LowerWidenableCondition.cpp:81
llvm::Pass
Pass interface - Implemented by all 'passes'.
Definition:
Pass.h:91
Instructions.h
SmallVector.h
llvm::PatternMatch
Definition:
PatternMatch.h:47
llvm::AnalysisManager
A container for analyses that lazily runs them and caches their results.
Definition:
InstructionSimplify.h:42
llvm::createLowerWidenableConditionPass
Pass * createLowerWidenableConditionPass()
llvm::FunctionPass
FunctionPass class - This class is used to implement most global optimizations.
Definition:
Pass.h:308
InitializePasses.h
llvm::Intrinsic::ID
unsigned ID
Definition:
TargetTransformInfo.h:37
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