[llvm] r274320 - Revert "code hoisting pass based on GVN"
Duncan P. N. Exon Smith via llvm-commits
llvm-commits at lists.llvm.org
Thu Jun 30 18:51:40 PDT 2016
Author: dexonsmith
Date: Thu Jun 30 20:51:40 2016
New Revision: 274320
URL: http://llvm.org/viewvc/llvm-project?rev=274320&view=rev
Log:
Revert "code hoisting pass based on GVN"
This reverts commit r274305, since it breaks self-hosting:
http://lab.llvm.org:8080/green/job/clang-stage1-configure-RA_build/22349/
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules/builds/17232
Note that the blamelist on lab.llvm.org:8011 is incorrect. The previous
build was r274299, but somehow r274305 wasn't included in the blamelist:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules
Removed:
llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp
llvm/trunk/test/Transforms/GVN/hoist.ll
Modified:
llvm/trunk/include/llvm/InitializePasses.h
llvm/trunk/include/llvm/LinkAllPasses.h
llvm/trunk/include/llvm/Transforms/Scalar.h
llvm/trunk/include/llvm/Transforms/Scalar/GVN.h
llvm/trunk/lib/Passes/PassRegistry.def
llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
llvm/trunk/lib/Transforms/Scalar/CMakeLists.txt
llvm/trunk/lib/Transforms/Scalar/Scalar.cpp
Modified: llvm/trunk/include/llvm/InitializePasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/include/llvm/InitializePasses.h (original)
+++ llvm/trunk/include/llvm/InitializePasses.h Thu Jun 30 20:51:40 2016
@@ -119,7 +119,6 @@ void initializeEarlyIfConverterPass(Pass
void initializeEdgeBundlesPass(PassRegistry&);
void initializeEfficiencySanitizerPass(PassRegistry&);
void initializeEliminateAvailableExternallyLegacyPassPass(PassRegistry &);
-void initializeGVNHoistLegacyPassPass(PassRegistry &);
void initializeExpandISelPseudosPass(PassRegistry&);
void initializeExpandPostRAPass(PassRegistry&);
void initializeExternalAAWrapperPassPass(PassRegistry&);
Modified: llvm/trunk/include/llvm/LinkAllPasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/LinkAllPasses.h?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/include/llvm/LinkAllPasses.h (original)
+++ llvm/trunk/include/llvm/LinkAllPasses.h Thu Jun 30 20:51:40 2016
@@ -158,7 +158,6 @@ namespace {
(void) llvm::createConstantHoistingPass();
(void) llvm::createCodeGenPreparePass();
(void) llvm::createEarlyCSEPass();
- (void) llvm::createGVNHoistPass();
(void) llvm::createMergedLoadStoreMotionPass();
(void) llvm::createGVNPass();
(void) llvm::createMemCpyOptPass();
Modified: llvm/trunk/include/llvm/Transforms/Scalar.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Scalar.h?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Scalar.h (original)
+++ llvm/trunk/include/llvm/Transforms/Scalar.h Thu Jun 30 20:51:40 2016
@@ -326,13 +326,6 @@ FunctionPass *createEarlyCSEPass();
//===----------------------------------------------------------------------===//
//
-// GVNHoist - This pass performs a simple and fast GVN pass over the dominator
-// tree to hoist common expressions from sibling branches.
-//
-FunctionPass *createGVNHoistPass();
-
-//===----------------------------------------------------------------------===//
-//
// MergedLoadStoreMotion - This pass merges loads and stores in diamonds. Loads
// are hoisted into the header, while stores sink into the footer.
//
Modified: llvm/trunk/include/llvm/Transforms/Scalar/GVN.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Scalar/GVN.h?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Scalar/GVN.h (original)
+++ llvm/trunk/include/llvm/Transforms/Scalar/GVN.h Thu Jun 30 20:51:40 2016
@@ -58,7 +58,11 @@ public:
AliasAnalysis *getAliasAnalysis() const { return VN.getAliasAnalysis(); }
MemoryDependenceResults &getMemDep() const { return *MD; }
+private:
+ friend class gvn::GVNLegacyPass;
+
struct Expression;
+ friend struct DenseMapInfo<Expression>;
/// This class holds the mapping between values and value numbers. It is used
/// as an efficient mechanism to determine the expression-wise equivalence of
@@ -100,10 +104,6 @@ public:
void verifyRemoved(const Value *) const;
};
-private:
- friend class gvn::GVNLegacyPass;
- friend struct DenseMapInfo<Expression>;
-
MemoryDependenceResults *MD;
DominatorTree *DT;
const TargetLibraryInfo *TLI;
@@ -228,13 +228,6 @@ private:
/// loads are eliminated by the pass.
FunctionPass *createGVNPass(bool NoLoads = false);
-/// \brief A simple and fast domtree-based GVN pass to hoist common expressions
-/// from sibling branches.
-struct GVNHoistPass : PassInfoMixin<GVNHoistPass> {
- /// \brief Run the pass over the function.
- PreservedAnalyses run(Function &F, AnalysisManager<Function> &AM);
-};
-
}
#endif
Modified: llvm/trunk/lib/Passes/PassRegistry.def
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Passes/PassRegistry.def?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/lib/Passes/PassRegistry.def (original)
+++ llvm/trunk/lib/Passes/PassRegistry.def Thu Jun 30 20:51:40 2016
@@ -128,7 +128,6 @@ FUNCTION_PASS("bdce", BDCEPass())
FUNCTION_PASS("dce", DCEPass())
FUNCTION_PASS("dse", DSEPass())
FUNCTION_PASS("early-cse", EarlyCSEPass())
-FUNCTION_PASS("gvn-hoist", GVNHoistPass())
FUNCTION_PASS("instcombine", InstCombinePass())
FUNCTION_PASS("invalidate<all>", InvalidateAllAnalysesPass())
FUNCTION_PASS("float2int", Float2IntPass())
Modified: llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp Thu Jun 30 20:51:40 2016
@@ -199,7 +199,6 @@ void PassManagerBuilder::populateFunctio
FPM.add(createCFGSimplificationPass());
FPM.add(createSROAPass());
FPM.add(createEarlyCSEPass());
- FPM.add(createGVNHoistPass());
FPM.add(createLowerExpectIntrinsicPass());
}
Modified: llvm/trunk/lib/Transforms/Scalar/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/CMakeLists.txt?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/CMakeLists.txt (original)
+++ llvm/trunk/lib/Transforms/Scalar/CMakeLists.txt Thu Jun 30 20:51:40 2016
@@ -12,7 +12,6 @@ add_llvm_library(LLVMScalarOpts
Float2Int.cpp
GuardWidening.cpp
GVN.cpp
- GVNHoist.cpp
InductiveRangeCheckElimination.cpp
IndVarSimplify.cpp
JumpThreading.cpp
Removed: llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp?rev=274319&view=auto
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp (removed)
@@ -1,740 +0,0 @@
-//===- GVNHoist.cpp - Hoist scalar and load expressions -------------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass hoists expressions from branches to a common dominator. It uses
-// GVN (global value numbering) to discover expressions computing the same
-// values. The primary goal is to reduce the code size, and in some
-// cases reduce critical path (by exposing more ILP).
-// Hoisting may affect the performance in some cases. To mitigate that, hoisting
-// is disabled in the following cases.
-// 1. Scalars across calls.
-// 2. geps when corresponding load/store cannot be hoisted.
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Scalar/GVN.h"
-#include "llvm/Transforms/Utils/MemorySSA.h"
-#include <functional>
-#include <unordered_map>
-#include <vector>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "gvn-hoist"
-
-STATISTIC(NumHoisted, "Number of instructions hoisted");
-STATISTIC(NumRemoved, "Number of instructions removed");
-STATISTIC(NumLoadsHoisted, "Number of loads hoisted");
-STATISTIC(NumLoadsRemoved, "Number of loads removed");
-STATISTIC(NumStoresHoisted, "Number of stores hoisted");
-STATISTIC(NumStoresRemoved, "Number of stores removed");
-STATISTIC(NumCallsHoisted, "Number of calls hoisted");
-STATISTIC(NumCallsRemoved, "Number of calls removed");
-
-static cl::opt<int>
- MaxHoistedThreshold("gvn-max-hoisted", cl::Hidden, cl::init(-1),
- cl::desc("Max number of instructions to hoist "
- "(default unlimited = -1)"));
-static cl::opt<int> MaxNumberOfBBSInPath(
- "gvn-hoist-max-bbs", cl::Hidden, cl::init(4),
- cl::desc("Max number of basic blocks on the path between "
- "hoisting locations (default = 4, unlimited = -1)"));
-
-static int HoistedCtr = 0;
-
-namespace {
-
-// Provides a sorting function based on the execution order of two instructions.
-struct SortByDFSIn {
-private:
- DenseMap<const BasicBlock *, unsigned> &DFSNumber;
-
-public:
- SortByDFSIn(DenseMap<const BasicBlock *, unsigned> &D) : DFSNumber(D) {}
-
- // Returns true when A executes before B.
- bool operator()(const Instruction *A, const Instruction *B) const {
- assert(A != B);
- const BasicBlock *BA = A->getParent();
- const BasicBlock *BB = B->getParent();
- unsigned NA = DFSNumber[BA];
- unsigned NB = DFSNumber[BB];
- if (NA < NB)
- return true;
- if (NA == NB) {
- // Sort them in the order they occur in the same basic block.
- BasicBlock::const_iterator AI(A), BI(B);
- return std::distance(AI, BI) < 0;
- }
- return false;
- }
-};
-
-// A map from a VN (value number) to all the instructions with that VN.
-typedef DenseMap<unsigned, SmallVector<Instruction *, 4>> VNtoInsns;
-
-// Records all scalar instructions candidate for code hoisting.
-class InsnInfo {
- VNtoInsns VNtoScalars;
-
-public:
- // Inserts I and its value number in VNtoScalars.
- void insert(Instruction *I, GVN::ValueTable &VN) {
- // Scalar instruction.
- unsigned V = VN.lookupOrAdd(I);
- VNtoScalars[V].push_back(I);
- }
-
- const VNtoInsns &getVNTable() const { return VNtoScalars; }
-};
-
-// Records all load instructions candidate for code hoisting.
-class LoadInfo {
- VNtoInsns VNtoLoads;
-
-public:
- // Insert Load and the value number of its memory address in VNtoLoads.
- void insert(LoadInst *Load, GVN::ValueTable &VN) {
- if (Load->isSimple()) {
- unsigned V = VN.lookupOrAdd(Load->getPointerOperand());
- VNtoLoads[V].push_back(Load);
- }
- }
-
- const VNtoInsns &getVNTable() const { return VNtoLoads; }
-};
-
-// Records all store instructions candidate for code hoisting.
-class StoreInfo {
- VNtoInsns VNtoStores;
-
-public:
- // Insert the Store and a hash number of the store address and the stored
- // value in VNtoStores.
- void insert(StoreInst *Store, GVN::ValueTable &VN) {
- if (!Store->isSimple())
- return;
- // Hash the store address and the stored value.
- Value *Ptr = Store->getPointerOperand();
- Value *Val = Store->getValueOperand();
- VNtoStores[hash_combine(VN.lookupOrAdd(Ptr), VN.lookupOrAdd(Val))]
- .push_back(Store);
- }
-
- const VNtoInsns &getVNTable() const { return VNtoStores; }
-};
-
-// Records all call instructions candidate for code hoisting.
-class CallInfo {
- VNtoInsns VNtoCallsScalars;
- VNtoInsns VNtoCallsLoads;
- VNtoInsns VNtoCallsStores;
-
-public:
- // Insert Call and its value numbering in one of the VNtoCalls* containers.
- void insert(CallInst *Call, GVN::ValueTable &VN) {
- // A call that doesNotAccessMemory is handled as a Scalar,
- // onlyReadsMemory will be handled as a Load instruction,
- // all other calls will be handled as stores.
- unsigned V = VN.lookupOrAdd(Call);
-
- if (Call->doesNotAccessMemory())
- VNtoCallsScalars[V].push_back(Call);
- else if (Call->onlyReadsMemory())
- VNtoCallsLoads[V].push_back(Call);
- else
- VNtoCallsStores[V].push_back(Call);
- }
-
- const VNtoInsns &getScalarVNTable() const { return VNtoCallsScalars; }
-
- const VNtoInsns &getLoadVNTable() const { return VNtoCallsLoads; }
-
- const VNtoInsns &getStoreVNTable() const { return VNtoCallsStores; }
-};
-
-typedef DenseMap<const BasicBlock *, bool> BBSideEffectsSet;
-typedef SmallVector<Instruction *, 4> SmallVecInsn;
-typedef SmallVectorImpl<Instruction *> SmallVecImplInsn;
-
-// This pass hoists common computations across branches sharing common
-// dominator. The primary goal is to reduce the code size, and in some
-// cases reduce critical path (by exposing more ILP).
-class GVNHoistLegacyPassImpl {
-public:
- GVN::ValueTable VN;
- DominatorTree *DT;
- AliasAnalysis *AA;
- MemoryDependenceResults *MD;
- DenseMap<const BasicBlock *, unsigned> DFSNumber;
- BBSideEffectsSet BBSideEffects;
- MemorySSA *MSSA;
- enum InsKind { Unknown, Scalar, Load, Store };
-
- GVNHoistLegacyPassImpl(DominatorTree *Dt, AliasAnalysis *Aa,
- MemoryDependenceResults *Md)
- : DT(Dt), AA(Aa), MD(Md) {}
-
- // Return true when there are exception handling in BB.
- bool hasEH(const BasicBlock *BB) {
- auto It = BBSideEffects.find(BB);
- if (It != BBSideEffects.end())
- return It->second;
-
- if (BB->isEHPad() || BB->hasAddressTaken()) {
- BBSideEffects[BB] = true;
- return true;
- }
-
- if (BB->getTerminator()->mayThrow()) {
- BBSideEffects[BB] = true;
- return true;
- }
-
- BBSideEffects[BB] = false;
- return false;
- }
-
- // Return true when all paths from A to the end of the function pass through
- // either B or C.
- bool hoistingFromAllPaths(const BasicBlock *A, const BasicBlock *B,
- const BasicBlock *C) {
- // We fully copy the WL in order to be able to remove items from it.
- SmallPtrSet<const BasicBlock *, 2> WL;
- WL.insert(B);
- WL.insert(C);
-
- for (auto It = df_begin(A), E = df_end(A); It != E;) {
- // There exists a path from A to the exit of the function if we are still
- // iterating in DF traversal and we removed all instructions from the work
- // list.
- if (WL.empty())
- return false;
-
- const BasicBlock *BB = *It;
- if (WL.erase(BB)) {
- // Stop DFS traversal when BB is in the work list.
- It.skipChildren();
- continue;
- }
-
- // Check for end of function, calls that do not return, etc.
- if (!isGuaranteedToTransferExecutionToSuccessor(BB->getTerminator()))
- return false;
-
- // Increment DFS traversal when not skipping children.
- ++It;
- }
-
- return true;
- }
-
- // Each element of a hoisting list contains the basic block where to hoist and
- // a list of instructions to be hoisted.
- typedef std::pair<BasicBlock *, SmallVecInsn> HoistingPointInfo;
- typedef SmallVector<HoistingPointInfo, 4> HoistingPointList;
-
- // Return true when there are users of A in one of the BBs of Paths.
- bool hasMemoryUse(MemoryAccess *A, const BasicBlock *PBB) {
- Value::user_iterator UI = A->user_begin();
- Value::user_iterator UE = A->user_end();
- const BasicBlock *BBA = A->getBlock();
- for (; UI != UE; ++UI)
- if (MemoryAccess *UM = dyn_cast<MemoryAccess>(*UI)) {
- if (PBB == BBA)
- if (MSSA->locallyDominates(UM, A))
- return true;
- if (PBB == UM->getBlock())
- return true;
- }
- return false;
- }
-
- // Check whether it is possible to hoist in between NewHoistPt and BBInsn.
- bool safeToHoist(const BasicBlock *NewHoistPt, const BasicBlock *BBInsn,
- InsKind K, int &NBBsOnAllPaths, MemoryAccess *MemdefInsn,
- BasicBlock *BBMemdefInsn, MemoryAccess *MemdefFirst,
- BasicBlock *BBMemdefFirst) {
- assert(DT->dominates(NewHoistPt, BBInsn) && "Invalid path");
-
- // Record in Paths all basic blocks reachable in depth-first iteration on
- // the inverse CFG from BBInsn to NewHoistPt. These blocks are all the
- // blocks that may be executed between the execution of NewHoistPt and
- // BBInsn. Hoisting an expression from BBInsn into NewHoistPt has to be safe
- // on all execution paths.
- for (auto I = idf_begin(BBInsn), E = idf_end(BBInsn); I != E;) {
- if (*I == NewHoistPt) {
- // Stop traversal when reaching NewHoistPt.
- I.skipChildren();
- continue;
- }
-
- // The safety checks for BBInsn will be handled separately.
- if (*I != BBInsn) {
- // Stop gathering blocks when it is not possible to hoist.
- if (hasEH(*I))
- return false;
-
- // Check that we do not move a store past loads.
- if (K == InsKind::Store) {
- if (DT->dominates(BBMemdefInsn, NewHoistPt))
- if (hasMemoryUse(MemdefInsn, *I))
- return false;
-
- if (DT->dominates(BBMemdefFirst, NewHoistPt))
- if (hasMemoryUse(MemdefFirst, *I))
- return false;
- }
- }
- ++NBBsOnAllPaths;
- ++I;
- }
-
- // Check whether there are too many blocks on the hoisting path.
- if (MaxNumberOfBBSInPath != -1 && NBBsOnAllPaths >= MaxNumberOfBBSInPath)
- return false;
-
- return true;
- }
-
- // Return true when it is safe to hoist an instruction Insn to NewHoistPt and
- // move the insertion point from HoistPt to NewHoistPt.
- bool safeToHoist(const BasicBlock *NewHoistPt, const BasicBlock *HoistPt,
- const Instruction *Insn, const Instruction *First, InsKind K,
- int &NBBsOnAllPaths) {
- if (hasEH(HoistPt))
- return false;
-
- const BasicBlock *BBInsn = Insn->getParent();
- // When HoistPt already contains an instruction to be hoisted, the
- // expression is needed on all paths.
-
- // Check that the hoisted expression is needed on all paths: it is unsafe
- // to hoist loads to a place where there may be a path not loading from
- // the same address: for instance there may be a branch on which the
- // address of the load may not be initialized. FIXME: at -Oz we may want
- // to hoist scalars to a place where they are partially needed.
- if (BBInsn != NewHoistPt &&
- !hoistingFromAllPaths(NewHoistPt, HoistPt, BBInsn))
- return false;
-
- MemoryAccess *MemdefInsn = nullptr;
- MemoryAccess *MemdefFirst = nullptr;
- BasicBlock *BBMemdefInsn = nullptr;
- BasicBlock *BBMemdefFirst = nullptr;
-
- if (K != InsKind::Scalar) {
- // For loads and stores, we check for dependences on the Memory SSA.
- MemdefInsn = cast<MemoryUseOrDef>(MSSA->getMemoryAccess(Insn))
- ->getDefiningAccess();
- BBMemdefInsn = MemdefInsn->getBlock();
-
- if (DT->properlyDominates(NewHoistPt, BBMemdefInsn))
- // Cannot move Insn past BBMemdefInsn to NewHoistPt.
- return false;
-
- MemdefFirst = cast<MemoryUseOrDef>(MSSA->getMemoryAccess(First))
- ->getDefiningAccess();
- BBMemdefFirst = MemdefFirst->getBlock();
-
- if (DT->properlyDominates(NewHoistPt, BBMemdefFirst))
- // Cannot move First past BBMemdefFirst to NewHoistPt.
- return false;
- }
-
- // Check for unsafe hoistings due to side effects.
- if (!safeToHoist(NewHoistPt, HoistPt, K, NBBsOnAllPaths, MemdefInsn,
- BBMemdefInsn, MemdefFirst, BBMemdefFirst) ||
- !safeToHoist(NewHoistPt, BBInsn, K, NBBsOnAllPaths, MemdefInsn,
- BBMemdefInsn, MemdefFirst, BBMemdefFirst))
- return false;
-
- // Safe to hoist scalars.
- if (K == InsKind::Scalar)
- return true;
-
- if (DT->properlyDominates(BBMemdefInsn, NewHoistPt) &&
- DT->properlyDominates(BBMemdefFirst, NewHoistPt))
- return true;
-
- const BasicBlock *BBFirst = First->getParent();
- if (BBInsn == BBFirst)
- return false;
-
- assert(BBMemdefInsn == NewHoistPt || BBMemdefFirst == NewHoistPt);
-
- if (BBInsn != NewHoistPt && BBFirst != NewHoistPt)
- return true;
-
- if (BBInsn == NewHoistPt) {
- if (DT->properlyDominates(BBMemdefFirst, NewHoistPt))
- return true;
- assert(BBInsn == BBMemdefFirst);
- if (MSSA->locallyDominates(MSSA->getMemoryAccess(Insn), MemdefFirst))
- return false;
- return true;
- }
-
- if (BBFirst == NewHoistPt) {
- if (DT->properlyDominates(BBMemdefInsn, NewHoistPt))
- return true;
- assert(BBFirst == BBMemdefInsn);
- if (MSSA->locallyDominates(MSSA->getMemoryAccess(First), MemdefInsn))
- return false;
- return true;
- }
-
- // No side effects: it is safe to hoist.
- return true;
- }
-
- // Partition InstructionsToHoist into a set of candidates which can share a
- // common hoisting point. The partitions are collected in HPL. IsScalar is
- // true when the instructions in InstructionsToHoist are scalars. IsLoad is
- // true when the InstructionsToHoist are loads, false when they are stores.
- void partitionCandidates(SmallVecImplInsn &InstructionsToHoist,
- HoistingPointList &HPL, InsKind K) {
- // No need to sort for two instructions.
- if (InstructionsToHoist.size() > 2) {
- SortByDFSIn Pred(DFSNumber);
- std::sort(InstructionsToHoist.begin(), InstructionsToHoist.end(), Pred);
- }
-
- // Create a work list of all the BB of the Insns to be hoisted.
- SmallPtrSet<BasicBlock *, 4> WL;
- SmallVecImplInsn::iterator II = InstructionsToHoist.begin();
- SmallVecImplInsn::iterator Start = II;
- BasicBlock *HoistPt = (*II)->getParent();
- WL.insert((*II)->getParent());
- int NBBsOnAllPaths = 0;
-
- for (++II; II != InstructionsToHoist.end(); ++II) {
- Instruction *Insn = *II;
- BasicBlock *BB = Insn->getParent();
- BasicBlock *NewHoistPt = DT->findNearestCommonDominator(HoistPt, BB);
- WL.insert(BB);
- if (safeToHoist(NewHoistPt, HoistPt, Insn, *Start, K, NBBsOnAllPaths)) {
- // Extend HoistPt to NewHoistPt.
- HoistPt = NewHoistPt;
- continue;
- }
- // Not safe to hoist: save the previous work list and start over from BB.
- if (std::distance(Start, II) > 1)
- HPL.push_back(std::make_pair(HoistPt, SmallVecInsn(Start, II)));
- else
- WL.clear();
-
- // We start over to compute HoistPt from BB.
- Start = II;
- HoistPt = BB;
- NBBsOnAllPaths = 0;
- }
-
- // Save the last partition.
- if (std::distance(Start, II) > 1)
- HPL.push_back(std::make_pair(HoistPt, SmallVecInsn(Start, II)));
- }
-
- // Initialize HPL from Map.
- void computeInsertionPoints(const VNtoInsns &Map, HoistingPointList &HPL,
- InsKind K) {
- for (VNtoInsns::const_iterator It = Map.begin(); It != Map.end(); ++It) {
- if (MaxHoistedThreshold != -1 && ++HoistedCtr > MaxHoistedThreshold)
- return;
-
- const SmallVecInsn &V = It->second;
- if (V.size() < 2)
- continue;
-
- // Compute the insertion point and the list of expressions to be hoisted.
- SmallVecInsn InstructionsToHoist;
- for (auto I : V)
- if (!hasEH(I->getParent()))
- InstructionsToHoist.push_back(I);
-
- if (InstructionsToHoist.size())
- partitionCandidates(InstructionsToHoist, HPL, K);
- }
- }
-
- // Return true when all operands of Instr are available at insertion point
- // HoistPt. When limiting the number of hoisted expressions, one could hoist
- // a load without hoisting its access function. So before hoisting any
- // expression, make sure that all its operands are available at insert point.
- bool allOperandsAvailable(const Instruction *I,
- const BasicBlock *HoistPt) const {
- for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
- const Value *Op = I->getOperand(i);
- const Instruction *Inst = dyn_cast<Instruction>(Op);
- if (Inst && !DT->dominates(Inst->getParent(), HoistPt))
- return false;
- }
-
- return true;
- }
-
- Instruction *firstOfTwo(Instruction *I, Instruction *J) const {
- for (Instruction &I1 : *I->getParent())
- if (&I1 == I || &I1 == J)
- return &I1;
- llvm_unreachable("Both I and J must be from same BB");
- }
-
- // Replace the use of From with To in Insn.
- void replaceUseWith(Instruction *Insn, Value *From, Value *To) const {
- for (Value::use_iterator UI = From->use_begin(), UE = From->use_end();
- UI != UE;) {
- Use &U = *UI++;
- if (U.getUser() == Insn) {
- U.set(To);
- return;
- }
- }
- llvm_unreachable("should replace exactly once");
- }
-
- bool makeOperandsAvailable(Instruction *Repl, BasicBlock *HoistPt) const {
- // Check whether the GEP of a ld/st can be synthesized at HoistPt.
- Instruction *Gep = nullptr;
- Instruction *Val = nullptr;
- if (LoadInst *Ld = dyn_cast<LoadInst>(Repl))
- Gep = dyn_cast<Instruction>(Ld->getPointerOperand());
- if (StoreInst *St = dyn_cast<StoreInst>(Repl)) {
- Gep = dyn_cast<Instruction>(St->getPointerOperand());
- Val = dyn_cast<Instruction>(St->getValueOperand());
- }
-
- if (!Gep || !isa<GetElementPtrInst>(Gep))
- return false;
-
- // Check whether we can compute the Gep at HoistPt.
- if (!allOperandsAvailable(Gep, HoistPt))
- return false;
-
- // Also check that the stored value is available.
- if (Val && !allOperandsAvailable(Val, HoistPt))
- return false;
-
- // Copy the gep before moving the ld/st.
- Instruction *ClonedGep = Gep->clone();
- ClonedGep->insertBefore(HoistPt->getTerminator());
- replaceUseWith(Repl, Gep, ClonedGep);
-
- // Also copy Val when it is a gep: geps are not hoisted by default.
- if (Val && isa<GetElementPtrInst>(Val)) {
- Instruction *ClonedVal = Val->clone();
- ClonedVal->insertBefore(HoistPt->getTerminator());
- replaceUseWith(Repl, Val, ClonedVal);
- }
-
- return true;
- }
-
- std::pair<unsigned, unsigned> hoist(HoistingPointList &HPL) {
- unsigned NI = 0, NL = 0, NS = 0, NC = 0, NR = 0;
- for (const HoistingPointInfo &HP : HPL) {
- // Find out whether we already have one of the instructions in HoistPt,
- // in which case we do not have to move it.
- BasicBlock *HoistPt = HP.first;
- const SmallVecInsn &InstructionsToHoist = HP.second;
- Instruction *Repl = nullptr;
- for (Instruction *I : InstructionsToHoist)
- if (I->getParent() == HoistPt) {
- // If there are two instructions in HoistPt to be hoisted in place:
- // update Repl to be the first one, such that we can rename the uses
- // of the second based on the first.
- Repl = !Repl ? I : firstOfTwo(Repl, I);
- }
-
- if (Repl) {
- // Repl is already in HoistPt: it remains in place.
- assert(allOperandsAvailable(Repl, HoistPt) &&
- "instruction depends on operands that are not available");
- } else {
- // When we do not find Repl in HoistPt, select the first in the list
- // and move it to HoistPt.
- Repl = InstructionsToHoist.front();
-
- // We can move Repl in HoistPt only when all operands are available.
- // The order in which hoistings are done may influence the availability
- // of operands.
- if (!allOperandsAvailable(Repl, HoistPt) &&
- !makeOperandsAvailable(Repl, HoistPt))
- continue;
- Repl->moveBefore(HoistPt->getTerminator());
- }
-
- if (isa<LoadInst>(Repl))
- ++NL;
- else if (isa<StoreInst>(Repl))
- ++NS;
- else if (isa<CallInst>(Repl))
- ++NC;
- else // Scalar
- ++NI;
-
- // Remove and rename all other instructions.
- for (Instruction *I : InstructionsToHoist)
- if (I != Repl) {
- ++NR;
- if (isa<LoadInst>(Repl))
- ++NumLoadsRemoved;
- else if (isa<StoreInst>(Repl))
- ++NumStoresRemoved;
- else if (isa<CallInst>(Repl))
- ++NumCallsRemoved;
- I->replaceAllUsesWith(Repl);
- I->eraseFromParent();
- }
- }
-
- NumHoisted += NL + NS + NC + NI;
- NumRemoved += NR;
- NumLoadsHoisted += NL;
- NumStoresHoisted += NS;
- NumCallsHoisted += NC;
- return {NI, NL + NC + NS};
- }
-
- // Hoist all expressions. Returns Number of scalars hoisted
- // and number of non-scalars hoisted.
- std::pair<unsigned, unsigned> hoistExpressions(Function &F) {
- InsnInfo II;
- LoadInfo LI;
- StoreInfo SI;
- CallInfo CI;
- const bool OptForMinSize = F.optForMinSize();
- for (BasicBlock *BB : depth_first(&F.getEntryBlock())) {
- for (Instruction &I1 : *BB) {
- if (LoadInst *Load = dyn_cast<LoadInst>(&I1))
- LI.insert(Load, VN);
- else if (StoreInst *Store = dyn_cast<StoreInst>(&I1))
- SI.insert(Store, VN);
- else if (CallInst *Call = dyn_cast<CallInst>(&I1)) {
- if (IntrinsicInst *Intr = dyn_cast<IntrinsicInst>(Call)) {
- if (isa<DbgInfoIntrinsic>(Intr) ||
- Intr->getIntrinsicID() == Intrinsic::assume)
- continue;
- }
- if (Call->mayHaveSideEffects()) {
- if (!OptForMinSize)
- break;
- // We may continue hoisting across calls which write to memory.
- if (Call->mayThrow())
- break;
- }
- CI.insert(Call, VN);
- } else if (OptForMinSize || !isa<GetElementPtrInst>(&I1))
- // Do not hoist scalars past calls that may write to memory because
- // that could result in spills later. geps are handled separately.
- // TODO: We can relax this for targets like AArch64 as they have more
- // registers than X86.
- II.insert(&I1, VN);
- }
- }
-
- HoistingPointList HPL;
- computeInsertionPoints(II.getVNTable(), HPL, InsKind::Scalar);
- computeInsertionPoints(LI.getVNTable(), HPL, InsKind::Load);
- computeInsertionPoints(SI.getVNTable(), HPL, InsKind::Store);
- computeInsertionPoints(CI.getScalarVNTable(), HPL, InsKind::Scalar);
- computeInsertionPoints(CI.getLoadVNTable(), HPL, InsKind::Load);
- computeInsertionPoints(CI.getStoreVNTable(), HPL, InsKind::Store);
- return hoist(HPL);
- }
-
- bool run(Function &F) {
- VN.setDomTree(DT);
- VN.setAliasAnalysis(AA);
- VN.setMemDep(MD);
- bool Res = false;
-
- unsigned I = 0;
- for (const BasicBlock *BB : depth_first(&F.getEntryBlock()))
- DFSNumber.insert(std::make_pair(BB, ++I));
-
- // FIXME: use lazy evaluation of VN to avoid the fix-point computation.
- while (1) {
- // FIXME: only compute MemorySSA once. We need to update the analysis in
- // the same time as transforming the code.
- MemorySSA M(F, AA, DT);
- MSSA = &M;
-
- auto HoistStat = hoistExpressions(F);
- if (HoistStat.first + HoistStat.second == 0) {
- return Res;
- }
- if (HoistStat.second > 0) {
- // To address a limitation of the current GVN, we need to rerun the
- // hoisting after we hoisted loads in order to be able to hoist all
- // scalars dependent on the hoisted loads. Same for stores.
- VN.clear();
- }
- Res = true;
- }
-
- return Res;
- }
-};
-
-class GVNHoistLegacyPass : public FunctionPass {
-public:
- static char ID;
-
- GVNHoistLegacyPass() : FunctionPass(ID) {
- initializeGVNHoistLegacyPassPass(*PassRegistry::getPassRegistry());
- }
-
- bool runOnFunction(Function &F) override {
- auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
- auto &AA = getAnalysis<AAResultsWrapperPass>().getAAResults();
- auto &MD = getAnalysis<MemoryDependenceWrapperPass>().getMemDep();
-
- GVNHoistLegacyPassImpl G(&DT, &AA, &MD);
- return G.run(F);
- }
-
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<DominatorTreeWrapperPass>();
- AU.addRequired<AAResultsWrapperPass>();
- AU.addRequired<MemoryDependenceWrapperPass>();
- AU.addPreserved<DominatorTreeWrapperPass>();
- }
-};
-} // namespace
-
-PreservedAnalyses GVNHoistPass::run(Function &F,
- AnalysisManager<Function> &AM) {
- DominatorTree &DT = AM.getResult<DominatorTreeAnalysis>(F);
- AliasAnalysis &AA = AM.getResult<AAManager>(F);
- MemoryDependenceResults &MD = AM.getResult<MemoryDependenceAnalysis>(F);
-
- GVNHoistLegacyPassImpl G(&DT, &AA, &MD);
- if (!G.run(F))
- return PreservedAnalyses::all();
-
- PreservedAnalyses PA;
- PA.preserve<DominatorTreeAnalysis>();
- return PA;
-}
-
-char GVNHoistLegacyPass::ID = 0;
-INITIALIZE_PASS_BEGIN(GVNHoistLegacyPass, "gvn-hoist",
- "Early GVN Hoisting of Expressions", false, false)
-INITIALIZE_PASS_DEPENDENCY(MemoryDependenceWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
-INITIALIZE_PASS_END(GVNHoistLegacyPass, "gvn-hoist",
- "Early GVN Hoisting of Expressions", false, false)
-
-FunctionPass *llvm::createGVNHoistPass() { return new GVNHoistLegacyPass(); }
Modified: llvm/trunk/lib/Transforms/Scalar/Scalar.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/Scalar.cpp?rev=274320&r1=274319&r2=274320&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/Scalar.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/Scalar.cpp Thu Jun 30 20:51:40 2016
@@ -44,7 +44,6 @@ void llvm::initializeScalarOpts(PassRegi
initializeGuardWideningLegacyPassPass(Registry);
initializeGVNLegacyPassPass(Registry);
initializeEarlyCSELegacyPassPass(Registry);
- initializeGVNHoistLegacyPassPass(Registry);
initializeFlattenCFGPassPass(Registry);
initializeInductiveRangeCheckEliminationPass(Registry);
initializeIndVarSimplifyLegacyPassPass(Registry);
@@ -237,10 +236,6 @@ void LLVMAddEarlyCSEPass(LLVMPassManager
unwrap(PM)->add(createEarlyCSEPass());
}
-void LLVMAddGVNHoistLegacyPass(LLVMPassManagerRef PM) {
- unwrap(PM)->add(createGVNHoistPass());
-}
-
void LLVMAddTypeBasedAliasAnalysisPass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createTypeBasedAAWrapperPass());
}
Removed: llvm/trunk/test/Transforms/GVN/hoist.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/GVN/hoist.ll?rev=274319&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/GVN/hoist.ll (original)
+++ llvm/trunk/test/Transforms/GVN/hoist.ll (removed)
@@ -1,650 +0,0 @@
-; RUN: opt -gvn-hoist -S < %s | FileCheck %s
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
-
- at GlobalVar = internal global float 1.000000e+00
-
-; Check that all scalar expressions are hoisted.
-;
-; CHECK-LABEL: @scalarsHoisting
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: fsub
-; CHECK: fmul
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @scalarsHoisting(float %d, float %min, float %max, float %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- %sub = fsub float %min, %a
- %mul = fmul float %sub, %div
- %sub1 = fsub float %max, %a
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- %sub3 = fsub float %max, %a
- %mul4 = fmul float %sub3, %div
- %sub5 = fsub float %min, %a
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that all loads and scalars depending on the loads are hoisted.
-; Check that getelementptr computation gets hoisted before the load.
-;
-; CHECK-LABEL: @readsAndScalarsHoisting
-; CHECK: load
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: fsub
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @readsAndScalarsHoisting(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- %A = getelementptr float, float* %min, i32 1
- %0 = load float, float* %A, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %B = getelementptr float, float* %min, i32 1
- %5 = load float, float* %B, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that we do not hoist loads after a store: the first two loads will be
-; hoisted, and then the third load will not be hoisted.
-;
-; CHECK-LABEL: @readsAndWrites
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: store
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @readsAndWrites(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- store float %0, float* @GlobalVar
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that we do hoist loads when the store is above the insertion point.
-;
-; CHECK-LABEL: @readsAndWriteAboveInsertPt
-; CHECK: load
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @readsAndWriteAboveInsertPt(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- store float 0.000000e+00, float* @GlobalVar
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that dependent expressions are hoisted.
-; CHECK-LABEL: @dependentScalarsHoisting
-; CHECK: fsub
-; CHECK: fadd
-; CHECK: fdiv
-; CHECK: fmul
-; CHECK-NOT: fsub
-; CHECK-NOT: fadd
-; CHECK-NOT: fdiv
-; CHECK-NOT: fmul
-define float @dependentScalarsHoisting(float %a, float %b, i1 %c) {
-entry:
- br i1 %c, label %if.then, label %if.else
-
-if.then:
- %d = fsub float %b, %a
- %e = fadd float %d, %a
- %f = fdiv float %e, %a
- %g = fmul float %f, %a
- br label %if.end
-
-if.else:
- %h = fsub float %b, %a
- %i = fadd float %h, %a
- %j = fdiv float %i, %a
- %k = fmul float %j, %a
- br label %if.end
-
-if.end:
- %r = phi float [ %g, %if.then ], [ %k, %if.else ]
- ret float %r
-}
-
-; Check that all independent expressions are hoisted.
-; CHECK-LABEL: @independentScalarsHoisting
-; CHECK: fmul
-; CHECK: fadd
-; CHECK: fdiv
-; CHECK: fsub
-; CHECK-NOT: fsub
-; CHECK-NOT: fdiv
-; CHECK-NOT: fmul
-define float @independentScalarsHoisting(float %a, float %b, i1 %c) {
-entry:
- br i1 %c, label %if.then, label %if.else
-
-if.then:
- %d = fadd float %b, %a
- %e = fsub float %b, %a
- %f = fdiv float %b, %a
- %g = fmul float %b, %a
- br label %if.end
-
-if.else:
- %i = fadd float %b, %a
- %h = fsub float %b, %a
- %j = fdiv float %b, %a
- %k = fmul float %b, %a
- br label %if.end
-
-if.end:
- %p = phi float [ %d, %if.then ], [ %i, %if.else ]
- %q = phi float [ %e, %if.then ], [ %h, %if.else ]
- %r = phi float [ %f, %if.then ], [ %j, %if.else ]
- %s = phi float [ %g, %if.then ], [ %k, %if.else ]
- %t = fadd float %p, %q
- %u = fadd float %r, %s
- %v = fadd float %t, %u
- ret float %v
-}
-
-; Check that we hoist load and scalar expressions in triangles.
-; CHECK-LABEL: @triangleHoisting
-; CHECK: load
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @triangleHoisting(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.end
-
-if.then: ; preds = %entry
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.end: ; preds = %entry
- %p1 = phi float [ %mul2, %if.then ], [ 0.000000e+00, %entry ]
- %p2 = phi float [ %mul, %if.then ], [ 0.000000e+00, %entry ]
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
-
- %x = fadd float %p1, %mul6
- %y = fadd float %p2, %mul4
- %z = fadd float %x, %y
- ret float %z
-}
-
-; Check that we hoist load and scalar expressions in dominator.
-; CHECK-LABEL: @dominatorHoisting
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @dominatorHoisting(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.end
-
-if.then: ; preds = %entry
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %entry
- %p1 = phi float [ %mul4, %if.then ], [ 0.000000e+00, %entry ]
- %p2 = phi float [ %mul6, %if.then ], [ 0.000000e+00, %entry ]
-
- %x = fadd float %p1, %mul2
- %y = fadd float %p2, %mul
- %z = fadd float %x, %y
- ret float %z
-}
-
-; Check that we hoist load and scalar expressions in dominator.
-; CHECK-LABEL: @domHoisting
-; CHECK: load
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK: load
-; CHECK: fsub
-; CHECK: fmul
-; CHECK-NOT: load
-; CHECK-NOT: fmul
-; CHECK-NOT: fsub
-define float @domHoisting(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then:
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.else:
- %6 = load float, float* %max, align 4
- %7 = load float, float* %a, align 4
- %sub9 = fsub float %6, %7
- %mul10 = fmul float %sub9, %div
- %8 = load float, float* %min, align 4
- %sub12 = fsub float %8, %7
- %mul13 = fmul float %sub12, %div
- br label %if.end
-
-if.end:
- %p1 = phi float [ %mul4, %if.then ], [ %mul10, %if.else ]
- %p2 = phi float [ %mul6, %if.then ], [ %mul13, %if.else ]
-
- %x = fadd float %p1, %mul2
- %y = fadd float %p2, %mul
- %z = fadd float %x, %y
- ret float %z
-}
-
-; Check that we do not hoist loads past stores within a same basic block.
-; CHECK-LABEL: @noHoistInSingleBBWithStore
-; CHECK: load
-; CHECK: store
-; CHECK: load
-; CHECK: store
-define i32 @noHoistInSingleBBWithStore() {
-entry:
- %D = alloca i32, align 4
- %0 = bitcast i32* %D to i8*
- %bf = load i8, i8* %0, align 4
- %bf.clear = and i8 %bf, -3
- store i8 %bf.clear, i8* %0, align 4
- %bf1 = load i8, i8* %0, align 4
- %bf.clear1 = and i8 %bf1, 1
- store i8 %bf.clear1, i8* %0, align 4
- ret i32 0
-}
-
-; Check that we do not hoist loads past calls within a same basic block.
-; CHECK-LABEL: @noHoistInSingleBBWithCall
-; CHECK: load
-; CHECK: call
-; CHECK: load
-declare void @foo()
-define i32 @noHoistInSingleBBWithCall() {
-entry:
- %D = alloca i32, align 4
- %0 = bitcast i32* %D to i8*
- %bf = load i8, i8* %0, align 4
- %bf.clear = and i8 %bf, -3
- call void @foo()
- %bf1 = load i8, i8* %0, align 4
- %bf.clear1 = and i8 %bf1, 1
- ret i32 0
-}
-
-; Check that we do not hoist loads past stores in any branch of a diamond.
-; CHECK-LABEL: @noHoistInDiamondWithOneStore1
-; CHECK: fdiv
-; CHECK: fcmp
-; CHECK: br
-define float @noHoistInDiamondWithOneStore1(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- store float 0.000000e+00, float* @GlobalVar
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- ; There are no side effects on the if.else branch.
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
-
- %6 = load float, float* %max, align 4
- %7 = load float, float* %a, align 4
- %sub6 = fsub float %6, %7
- %mul7 = fmul float %sub6, %div
- %8 = load float, float* %min, align 4
- %sub8 = fsub float %8, %7
- %mul9 = fmul float %sub8, %div
-
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that we do not hoist loads past a store in any branch of a diamond.
-; CHECK-LABEL: @noHoistInDiamondWithOneStore2
-; CHECK: fdiv
-; CHECK: fcmp
-; CHECK: br
-define float @noHoistInDiamondWithOneStore2(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- ; There are no side effects on the if.then branch.
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %if.end
-
-if.else: ; preds = %entry
- store float 0.000000e+00, float* @GlobalVar
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- %tmax.0 = phi float [ %mul2, %if.then ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %if.then ], [ %mul4, %if.else ]
-
- %6 = load float, float* %max, align 4
- %7 = load float, float* %a, align 4
- %sub6 = fsub float %6, %7
- %mul7 = fmul float %sub6, %div
- %8 = load float, float* %min, align 4
- %sub8 = fsub float %8, %7
- %mul9 = fmul float %sub8, %div
-
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that we do not hoist loads outside a loop containing stores.
-; CHECK-LABEL: @noHoistInLoopsWithStores
-; CHECK: fdiv
-; CHECK: fcmp
-; CHECK: br
-define float @noHoistInLoopsWithStores(float %d, float* %min, float* %max, float* %a) {
-entry:
- %div = fdiv float 1.000000e+00, %d
- %cmp = fcmp oge float %div, 0.000000e+00
- br i1 %cmp, label %do.body, label %if.else
-
-do.body:
- %0 = load float, float* %min, align 4
- %1 = load float, float* %a, align 4
-
- ; It is unsafe to hoist the loads outside the loop because of the store.
- store float 0.000000e+00, float* @GlobalVar
-
- %sub = fsub float %0, %1
- %mul = fmul float %sub, %div
- %2 = load float, float* %max, align 4
- %sub1 = fsub float %2, %1
- %mul2 = fmul float %sub1, %div
- br label %while.cond
-
-while.cond:
- %cmp1 = fcmp oge float %mul2, 0.000000e+00
- br i1 %cmp1, label %if.end, label %do.body
-
-if.else:
- %3 = load float, float* %max, align 4
- %4 = load float, float* %a, align 4
- %sub3 = fsub float %3, %4
- %mul4 = fmul float %sub3, %div
- %5 = load float, float* %min, align 4
- %sub5 = fsub float %5, %4
- %mul6 = fmul float %sub5, %div
- br label %if.end
-
-if.end:
- %tmax.0 = phi float [ %mul2, %while.cond ], [ %mul6, %if.else ]
- %tmin.0 = phi float [ %mul, %while.cond ], [ %mul4, %if.else ]
-
- %add = fadd float %tmax.0, %tmin.0
- ret float %add
-}
-
-; Check that we hoist stores: all the instructions from the then branch
-; should be hoisted.
-; CHECK-LABEL: @hoistStores
-; CHECK: zext
-; CHECK: trunc
-; CHECK: getelementptr
-; CHECK: load
-; CHECK: getelementptr
-; CHECK: store
-; CHECK: load
-; CHECK: load
-; CHECK: zext
-; CHECK: add
-; CHECK: store
-; CHECK: br
-; CHECK: if.then
-; CHECK: br
-
-%struct.foo = type { i16* }
-
-define void @hoistStores(%struct.foo* %s, i32* %coord, i1 zeroext %delta) {
-entry:
- %frombool = zext i1 %delta to i8
- %tobool = trunc i8 %frombool to i1
- br i1 %tobool, label %if.then, label %if.else
-
-if.then: ; preds = %entry
- %p = getelementptr inbounds %struct.foo, %struct.foo* %s, i32 0, i32 0
- %0 = load i16*, i16** %p, align 8
- %incdec.ptr = getelementptr inbounds i16, i16* %0, i32 1
- store i16* %incdec.ptr, i16** %p, align 8
- %1 = load i16, i16* %0, align 2
- %conv = zext i16 %1 to i32
- %2 = load i32, i32* %coord, align 4
- %add = add i32 %2, %conv
- store i32 %add, i32* %coord, align 4
- br label %if.end
-
-if.else: ; preds = %entry
- %p1 = getelementptr inbounds %struct.foo, %struct.foo* %s, i32 0, i32 0
- %3 = load i16*, i16** %p1, align 8
- %incdec.ptr2 = getelementptr inbounds i16, i16* %3, i32 1
- store i16* %incdec.ptr2, i16** %p1, align 8
- %4 = load i16, i16* %3, align 2
- %conv3 = zext i16 %4 to i32
- %5 = load i32, i32* %coord, align 4
- %add4 = add i32 %5, %conv3
- store i32 %add4, i32* %coord, align 4
- %6 = load i16*, i16** %p1, align 8
- %incdec.ptr6 = getelementptr inbounds i16, i16* %6, i32 1
- store i16* %incdec.ptr6, i16** %p1, align 8
- %7 = load i16, i16* %6, align 2
- %conv7 = zext i16 %7 to i32
- %shl = shl i32 %conv7, 8
- %8 = load i32, i32* %coord, align 4
- %add8 = add i32 %8, %shl
- store i32 %add8, i32* %coord, align 4
- br label %if.end
-
-if.end: ; preds = %if.else, %if.then
- ret void
-}
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