This patch provides an initial prototype for a pass that sinks instructions based on GVN information, similar to GVNHoist. It is not yet ready for commiting but I've uploaded it to gather some initial thoughts.
This pass attempts to sink instructions into successors, reducing static
instruction count and enabling if-conversion.
We use a variant of global value numbering to decide what can be sunk.
Consider:
[ %a1 = add i32 %b, 1 ] [ %c1 = add i32 %d, 1 ]
[ %a2 = xor i32 %a1, 1 ] [ %c2 = xor i32 %c1, 1 ]
\ /
[ %e = phi i32 %a2, %c2 ]
[ add i32 %e, 4 ]
GVN would number %a1 and %c1 differently because they compute different
results - the VN of an instruction is a function of its opcode and the
transitive closure of its operands. This is the key property for hoisting
and CSE.
What we want when sinking however is for a numbering that is a function of
the *uses* of an instruction, which allows us to answer the question "if I
replace %a1 with %c1, will it contribute in an equivalent way to all
successive instructions?". The (new) PostValueTable class in GVN provides this
mapping.
This pass has some shown really impressive improvements especially for codesize already on internal benchmarks, so I have high hopes it can replace all the sinking logic in SimplifyCFG.
Differential revision: https://reviews.llvm.org/D24805
llvm-svn: 303850
284 lines
9.2 KiB
C++
284 lines
9.2 KiB
C++
//===-- Scalar.cpp --------------------------------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements common infrastructure for libLLVMScalarOpts.a, which
|
|
// implements several scalar transformations over the LLVM intermediate
|
|
// representation, including the C bindings for that library.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Transforms/Scalar.h"
|
|
#include "llvm-c/Initialization.h"
|
|
#include "llvm-c/Transforms/Scalar.h"
|
|
#include "llvm/Analysis/BasicAliasAnalysis.h"
|
|
#include "llvm/Analysis/Passes.h"
|
|
#include "llvm/Analysis/ScopedNoAliasAA.h"
|
|
#include "llvm/Analysis/TypeBasedAliasAnalysis.h"
|
|
#include "llvm/Transforms/Scalar/GVN.h"
|
|
#include "llvm/Transforms/Scalar/SimpleLoopUnswitch.h"
|
|
#include "llvm/IR/DataLayout.h"
|
|
#include "llvm/IR/Verifier.h"
|
|
#include "llvm/InitializePasses.h"
|
|
#include "llvm/IR/LegacyPassManager.h"
|
|
|
|
using namespace llvm;
|
|
|
|
/// initializeScalarOptsPasses - Initialize all passes linked into the
|
|
/// ScalarOpts library.
|
|
void llvm::initializeScalarOpts(PassRegistry &Registry) {
|
|
initializeADCELegacyPassPass(Registry);
|
|
initializeBDCELegacyPassPass(Registry);
|
|
initializeAlignmentFromAssumptionsPass(Registry);
|
|
initializeConstantHoistingLegacyPassPass(Registry);
|
|
initializeConstantPropagationPass(Registry);
|
|
initializeCorrelatedValuePropagationPass(Registry);
|
|
initializeDCELegacyPassPass(Registry);
|
|
initializeDeadInstEliminationPass(Registry);
|
|
initializeScalarizerPass(Registry);
|
|
initializeDSELegacyPassPass(Registry);
|
|
initializeGuardWideningLegacyPassPass(Registry);
|
|
initializeGVNLegacyPassPass(Registry);
|
|
initializeNewGVNLegacyPassPass(Registry);
|
|
initializeEarlyCSELegacyPassPass(Registry);
|
|
initializeEarlyCSEMemSSALegacyPassPass(Registry);
|
|
initializeGVNHoistLegacyPassPass(Registry);
|
|
initializeGVNSinkLegacyPassPass(Registry);
|
|
initializeFlattenCFGPassPass(Registry);
|
|
initializeInductiveRangeCheckEliminationPass(Registry);
|
|
initializeIndVarSimplifyLegacyPassPass(Registry);
|
|
initializeInferAddressSpacesPass(Registry);
|
|
initializeJumpThreadingPass(Registry);
|
|
initializeLegacyLICMPassPass(Registry);
|
|
initializeLegacyLoopSinkPassPass(Registry);
|
|
initializeLoopDataPrefetchLegacyPassPass(Registry);
|
|
initializeLoopDeletionLegacyPassPass(Registry);
|
|
initializeLoopAccessLegacyAnalysisPass(Registry);
|
|
initializeLoopInstSimplifyLegacyPassPass(Registry);
|
|
initializeLoopInterchangePass(Registry);
|
|
initializeLoopPredicationLegacyPassPass(Registry);
|
|
initializeLoopRotateLegacyPassPass(Registry);
|
|
initializeLoopStrengthReducePass(Registry);
|
|
initializeLoopRerollPass(Registry);
|
|
initializeLoopUnrollPass(Registry);
|
|
initializeLoopUnswitchPass(Registry);
|
|
initializeLoopVersioningLICMPass(Registry);
|
|
initializeLoopIdiomRecognizeLegacyPassPass(Registry);
|
|
initializeLowerAtomicLegacyPassPass(Registry);
|
|
initializeLowerExpectIntrinsicPass(Registry);
|
|
initializeLowerGuardIntrinsicLegacyPassPass(Registry);
|
|
initializeMemCpyOptLegacyPassPass(Registry);
|
|
initializeMergedLoadStoreMotionLegacyPassPass(Registry);
|
|
initializeNaryReassociateLegacyPassPass(Registry);
|
|
initializePartiallyInlineLibCallsLegacyPassPass(Registry);
|
|
initializeReassociateLegacyPassPass(Registry);
|
|
initializeRegToMemPass(Registry);
|
|
initializeRewriteStatepointsForGCPass(Registry);
|
|
initializeSCCPLegacyPassPass(Registry);
|
|
initializeIPSCCPLegacyPassPass(Registry);
|
|
initializeSROALegacyPassPass(Registry);
|
|
initializeCFGSimplifyPassPass(Registry);
|
|
initializeLateCFGSimplifyPassPass(Registry);
|
|
initializeStructurizeCFGPass(Registry);
|
|
initializeSimpleLoopUnswitchLegacyPassPass(Registry);
|
|
initializeSinkingLegacyPassPass(Registry);
|
|
initializeTailCallElimPass(Registry);
|
|
initializeSeparateConstOffsetFromGEPPass(Registry);
|
|
initializeSpeculativeExecutionLegacyPassPass(Registry);
|
|
initializeStraightLineStrengthReducePass(Registry);
|
|
initializeLoadCombinePass(Registry);
|
|
initializePlaceBackedgeSafepointsImplPass(Registry);
|
|
initializePlaceSafepointsPass(Registry);
|
|
initializeFloat2IntLegacyPassPass(Registry);
|
|
initializeLoopDistributeLegacyPass(Registry);
|
|
initializeLoopLoadEliminationPass(Registry);
|
|
initializeLoopSimplifyCFGLegacyPassPass(Registry);
|
|
initializeLoopVersioningPassPass(Registry);
|
|
}
|
|
|
|
void LLVMInitializeScalarOpts(LLVMPassRegistryRef R) {
|
|
initializeScalarOpts(*unwrap(R));
|
|
}
|
|
|
|
void LLVMAddAggressiveDCEPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createAggressiveDCEPass());
|
|
}
|
|
|
|
void LLVMAddBitTrackingDCEPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createBitTrackingDCEPass());
|
|
}
|
|
|
|
void LLVMAddAlignmentFromAssumptionsPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createAlignmentFromAssumptionsPass());
|
|
}
|
|
|
|
void LLVMAddCFGSimplificationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createCFGSimplificationPass());
|
|
}
|
|
|
|
void LLVMAddLateCFGSimplificationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLateCFGSimplificationPass());
|
|
}
|
|
|
|
void LLVMAddDeadStoreEliminationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createDeadStoreEliminationPass());
|
|
}
|
|
|
|
void LLVMAddScalarizerPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createScalarizerPass());
|
|
}
|
|
|
|
void LLVMAddGVNPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createGVNPass());
|
|
}
|
|
|
|
void LLVMAddNewGVNPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createNewGVNPass());
|
|
}
|
|
|
|
void LLVMAddMergedLoadStoreMotionPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createMergedLoadStoreMotionPass());
|
|
}
|
|
|
|
void LLVMAddIndVarSimplifyPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createIndVarSimplifyPass());
|
|
}
|
|
|
|
void LLVMAddInstructionCombiningPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createInstructionCombiningPass());
|
|
}
|
|
|
|
void LLVMAddJumpThreadingPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createJumpThreadingPass());
|
|
}
|
|
|
|
void LLVMAddLoopSinkPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopSinkPass());
|
|
}
|
|
|
|
void LLVMAddLICMPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLICMPass());
|
|
}
|
|
|
|
void LLVMAddLoopDeletionPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopDeletionPass());
|
|
}
|
|
|
|
void LLVMAddLoopIdiomPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopIdiomPass());
|
|
}
|
|
|
|
void LLVMAddLoopRotatePass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopRotatePass());
|
|
}
|
|
|
|
void LLVMAddLoopRerollPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopRerollPass());
|
|
}
|
|
|
|
void LLVMAddLoopSimplifyCFGPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopSimplifyCFGPass());
|
|
}
|
|
|
|
void LLVMAddLoopUnrollPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopUnrollPass());
|
|
}
|
|
|
|
void LLVMAddLoopUnswitchPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLoopUnswitchPass());
|
|
}
|
|
|
|
void LLVMAddMemCpyOptPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createMemCpyOptPass());
|
|
}
|
|
|
|
void LLVMAddPartiallyInlineLibCallsPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createPartiallyInlineLibCallsPass());
|
|
}
|
|
|
|
void LLVMAddLowerSwitchPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLowerSwitchPass());
|
|
}
|
|
|
|
void LLVMAddPromoteMemoryToRegisterPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createPromoteMemoryToRegisterPass());
|
|
}
|
|
|
|
void LLVMAddReassociatePass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createReassociatePass());
|
|
}
|
|
|
|
void LLVMAddSCCPPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createSCCPPass());
|
|
}
|
|
|
|
void LLVMAddScalarReplAggregatesPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createSROAPass());
|
|
}
|
|
|
|
void LLVMAddScalarReplAggregatesPassSSA(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createSROAPass());
|
|
}
|
|
|
|
void LLVMAddScalarReplAggregatesPassWithThreshold(LLVMPassManagerRef PM,
|
|
int Threshold) {
|
|
unwrap(PM)->add(createSROAPass());
|
|
}
|
|
|
|
void LLVMAddSimplifyLibCallsPass(LLVMPassManagerRef PM) {
|
|
// NOTE: The simplify-libcalls pass has been removed.
|
|
}
|
|
|
|
void LLVMAddTailCallEliminationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createTailCallEliminationPass());
|
|
}
|
|
|
|
void LLVMAddConstantPropagationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createConstantPropagationPass());
|
|
}
|
|
|
|
void LLVMAddDemoteMemoryToRegisterPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createDemoteRegisterToMemoryPass());
|
|
}
|
|
|
|
void LLVMAddVerifierPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createVerifierPass());
|
|
}
|
|
|
|
void LLVMAddCorrelatedValuePropagationPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createCorrelatedValuePropagationPass());
|
|
}
|
|
|
|
void LLVMAddEarlyCSEPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createEarlyCSEPass(false/*=UseMemorySSA*/));
|
|
}
|
|
|
|
void LLVMAddEarlyCSEMemSSAPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createEarlyCSEPass(true/*=UseMemorySSA*/));
|
|
}
|
|
|
|
void LLVMAddGVNHoistLegacyPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createGVNHoistPass());
|
|
}
|
|
|
|
void LLVMAddTypeBasedAliasAnalysisPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createTypeBasedAAWrapperPass());
|
|
}
|
|
|
|
void LLVMAddScopedNoAliasAAPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createScopedNoAliasAAWrapperPass());
|
|
}
|
|
|
|
void LLVMAddBasicAliasAnalysisPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createBasicAAWrapperPass());
|
|
}
|
|
|
|
void LLVMAddLowerExpectIntrinsicPass(LLVMPassManagerRef PM) {
|
|
unwrap(PM)->add(createLowerExpectIntrinsicPass());
|
|
}
|