From af0199863a6f4dbe8c50c73ba30936d375c68af0 Mon Sep 17 00:00:00 2001 From: Justin Bogner Date: Fri, 30 Oct 2015 23:13:18 +0000 Subject: [PATCH] [PM] Port ADCE to the new pass manager git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251725 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/InitializePasses.h | 2 +- include/llvm/Transforms/Scalar/ADCE.h | 38 +++++++++++++++++ lib/Passes/PassBuilder.cpp | 1 + lib/Passes/PassRegistry.def | 1 + lib/Transforms/Scalar/ADCE.cpp | 59 +++++++++++++++------------ lib/Transforms/Scalar/Scalar.cpp | 2 +- test/Transforms/ADCE/basictest.ll | 1 + 7 files changed, 76 insertions(+), 28 deletions(-) create mode 100644 include/llvm/Transforms/Scalar/ADCE.h diff --git a/include/llvm/InitializePasses.h b/include/llvm/InitializePasses.h index 3c2160292d5..7e572232d5b 100644 --- a/include/llvm/InitializePasses.h +++ b/include/llvm/InitializePasses.h @@ -61,7 +61,7 @@ void initializeTarget(PassRegistry&); void initializeAAEvalPass(PassRegistry&); void initializeAddDiscriminatorsPass(PassRegistry&); -void initializeADCEPass(PassRegistry&); +void initializeADCELegacyPassPass(PassRegistry&); void initializeBDCEPass(PassRegistry&); void initializeAliasSetPrinterPass(PassRegistry&); void initializeAlwaysInlinerPass(PassRegistry&); diff --git a/include/llvm/Transforms/Scalar/ADCE.h b/include/llvm/Transforms/Scalar/ADCE.h new file mode 100644 index 00000000000..f9bc7b77c14 --- /dev/null +++ b/include/llvm/Transforms/Scalar/ADCE.h @@ -0,0 +1,38 @@ +//===- ADCE.h - Aggressive dead code elimination --------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file provides the interface for the Aggressive Dead Code Elimination +// pass. This pass optimistically assumes that all instructions are dead until +// proven otherwise, allowing it to eliminate dead computations that other DCE +// passes do not catch, particularly involving loop computations. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_TRANSFORMS_SCALAR_ADCE_H +#define LLVM_TRANSFORMS_SCALAR_ADCE_H + +#include "llvm/IR/Function.h" +#include "llvm/IR/PassManager.h" + +namespace llvm { + +/// A DCE pass that assumes instructions are dead until proven otherwise. +/// +/// This pass eliminates dead code by optimistically assuming that all +/// instructions are dead until proven otherwise. This allows it to eliminate +/// dead computations that other DCE passes do not catch, particularly involving +/// loop computations. +class ADCEPass { +public: + static StringRef name() { return "ADCEPass"; } + PreservedAnalyses run(Function &F); +}; +} + +#endif // LLVM_TRANSFORMS_SCALAR_ADCE_H diff --git a/lib/Passes/PassBuilder.cpp b/lib/Passes/PassBuilder.cpp index b8f6e204a9c..f18fcb18575 100644 --- a/lib/Passes/PassBuilder.cpp +++ b/lib/Passes/PassBuilder.cpp @@ -30,6 +30,7 @@ #include "llvm/Support/Debug.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Transforms/InstCombine/InstCombine.h" +#include "llvm/Transforms/Scalar/ADCE.h" #include "llvm/Transforms/Scalar/EarlyCSE.h" #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h" #include "llvm/Transforms/Scalar/SimplifyCFG.h" diff --git a/lib/Passes/PassRegistry.def b/lib/Passes/PassRegistry.def index da4e63b1a16..6f523301f92 100644 --- a/lib/Passes/PassRegistry.def +++ b/lib/Passes/PassRegistry.def @@ -63,6 +63,7 @@ FUNCTION_ANALYSIS("targetir", #ifndef FUNCTION_PASS #define FUNCTION_PASS(NAME, CREATE_PASS) #endif +FUNCTION_PASS("adce", ADCEPass()) FUNCTION_PASS("early-cse", EarlyCSEPass()) FUNCTION_PASS("instcombine", InstCombinePass()) FUNCTION_PASS("invalidate", InvalidateAllAnalysesPass()) diff --git a/lib/Transforms/Scalar/ADCE.cpp b/lib/Transforms/Scalar/ADCE.cpp index c73766cc03a..590a52da6b1 100644 --- a/lib/Transforms/Scalar/ADCE.cpp +++ b/lib/Transforms/Scalar/ADCE.cpp @@ -14,7 +14,7 @@ // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/Scalar.h" +#include "llvm/Transforms/Scalar/ADCE.h" #include "llvm/ADT/DepthFirstIterator.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" @@ -26,35 +26,14 @@ #include "llvm/IR/Instructions.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/Pass.h" +#include "llvm/Transforms/Scalar.h" using namespace llvm; #define DEBUG_TYPE "adce" STATISTIC(NumRemoved, "Number of instructions removed"); -namespace { -struct ADCE : public FunctionPass { - static char ID; // Pass identification, replacement for typeid - ADCE() : FunctionPass(ID) { - initializeADCEPass(*PassRegistry::getPassRegistry()); - } - - bool runOnFunction(Function& F) override; - - void getAnalysisUsage(AnalysisUsage& AU) const override { - AU.setPreservesCFG(); - AU.addPreserved(); - } -}; -} - -char ADCE::ID = 0; -INITIALIZE_PASS(ADCE, "adce", "Aggressive Dead Code Elimination", false, false) - -bool ADCE::runOnFunction(Function& F) { - if (skipOptnoneFunction(F)) - return false; - +static bool aggressiveDCE(Function& F) { SmallPtrSet Alive; SmallVector Worklist; @@ -96,6 +75,34 @@ bool ADCE::runOnFunction(Function& F) { return !Worklist.empty(); } -FunctionPass *llvm::createAggressiveDCEPass() { - return new ADCE(); +PreservedAnalyses ADCEPass::run(Function &F) { + if (aggressiveDCE(F)) + return PreservedAnalyses::none(); + return PreservedAnalyses::all(); } + +namespace { +struct ADCELegacyPass : public FunctionPass { + static char ID; // Pass identification, replacement for typeid + ADCELegacyPass() : FunctionPass(ID) { + initializeADCELegacyPassPass(*PassRegistry::getPassRegistry()); + } + + bool runOnFunction(Function& F) override { + if (skipOptnoneFunction(F)) + return false; + return aggressiveDCE(F); + } + + void getAnalysisUsage(AnalysisUsage& AU) const override { + AU.setPreservesCFG(); + AU.addPreserved(); + } +}; +} + +char ADCELegacyPass::ID = 0; +INITIALIZE_PASS(ADCELegacyPass, "adce", "Aggressive Dead Code Elimination", + false, false) + +FunctionPass *llvm::createAggressiveDCEPass() { return new ADCELegacyPass(); } diff --git a/lib/Transforms/Scalar/Scalar.cpp b/lib/Transforms/Scalar/Scalar.cpp index f7a61343f4a..fd74fa84226 100644 --- a/lib/Transforms/Scalar/Scalar.cpp +++ b/lib/Transforms/Scalar/Scalar.cpp @@ -30,7 +30,7 @@ using namespace llvm; /// initializeScalarOptsPasses - Initialize all passes linked into the /// ScalarOpts library. void llvm::initializeScalarOpts(PassRegistry &Registry) { - initializeADCEPass(Registry); + initializeADCELegacyPassPass(Registry); initializeBDCEPass(Registry); initializeAlignmentFromAssumptionsPass(Registry); initializeConstantHoistingPass(Registry); diff --git a/test/Transforms/ADCE/basictest.ll b/test/Transforms/ADCE/basictest.ll index 61c4224df97..aaacc184225 100644 --- a/test/Transforms/ADCE/basictest.ll +++ b/test/Transforms/ADCE/basictest.ll @@ -1,4 +1,5 @@ ; RUN: opt < %s -adce -simplifycfg | llvm-dis +; RUN: opt < %s -passes=adce | llvm-dis define i32 @Test(i32 %A, i32 %B) { BB1: -- 2.34.1