//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "mergefunc"
#include "llvm/Transforms/IPO.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
+#include "llvm/IR/ValueHandle.h"
#include "llvm/Pass.h"
-#include "llvm/Support/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/raw_ostream.h"
#include <vector>
using namespace llvm;
+#define DEBUG_TYPE "mergefunc"
+
STATISTIC(NumFunctionsMerged, "Number of functions merged");
STATISTIC(NumThunksWritten, "Number of thunks generated");
STATISTIC(NumAliasesWritten, "Number of aliases generated");
static const ComparableFunction TombstoneKey;
static DataLayout * const LookupOnly;
- ComparableFunction(Function *Func, DataLayout *TD)
- : Func(Func), Hash(profileFunction(Func)), TD(TD) {}
+ ComparableFunction(Function *Func, const DataLayout *DL)
+ : Func(Func), Hash(profileFunction(Func)), DL(DL) {}
Function *getFunc() const { return Func; }
unsigned getHash() const { return Hash; }
- DataLayout *getTD() const { return TD; }
+ const DataLayout *getDataLayout() const { return DL; }
// Drops AssertingVH reference to the function. Outside of debug mode, this
// does nothing.
private:
explicit ComparableFunction(unsigned Hash)
- : Func(NULL), Hash(Hash), TD(NULL) {}
+ : Func(NULL), Hash(Hash), DL(NULL) {}
AssertingVH<Function> Func;
unsigned Hash;
- DataLayout *TD;
+ const DataLayout *DL;
};
const ComparableFunction ComparableFunction::EmptyKey = ComparableFunction(0);
/// side of claiming that two functions are different).
class FunctionComparator {
public:
- FunctionComparator(const DataLayout *TD, const Function *F1,
+ FunctionComparator(const DataLayout *DL, const Function *F1,
const Function *F2)
- : F1(F1), F2(F2), TD(TD) {}
+ : F1(F1), F2(F2), DL(DL) {}
/// Test whether the two functions have equivalent behaviour.
bool compare();
return isEquivalentGEP(cast<GEPOperator>(GEP1), cast<GEPOperator>(GEP2));
}
- /// Compare two Types, treating all pointer types as equal.
- bool isEquivalentType(Type *Ty1, Type *Ty2) const;
+ /// cmpType - compares two types,
+ /// defines total ordering among the types set.
+ ///
+ /// Return values:
+ /// 0 if types are equal,
+ /// -1 if Left is less than Right,
+ /// +1 if Left is greater than Right.
+ ///
+ /// Description:
+ /// Comparison is broken onto stages. Like in lexicographical comparison
+ /// stage coming first has higher priority.
+ /// On each explanation stage keep in mind total ordering properties.
+ ///
+ /// 0. Before comparison we coerce pointer types of 0 address space to
+ /// integer.
+ /// We also don't bother with same type at left and right, so
+ /// just return 0 in this case.
+ ///
+ /// 1. If types are of different kind (different type IDs).
+ /// Return result of type IDs comparison, treating them as numbers.
+ /// 2. If types are vectors or integers, compare Type* values as numbers.
+ /// 3. Types has same ID, so check whether they belongs to the next group:
+ /// * Void
+ /// * Float
+ /// * Double
+ /// * X86_FP80
+ /// * FP128
+ /// * PPC_FP128
+ /// * Label
+ /// * Metadata
+ /// If so - return 0, yes - we can treat these types as equal only because
+ /// their IDs are same.
+ /// 4. If Left and Right are pointers, return result of address space
+ /// comparison (numbers comparison). We can treat pointer types of same
+ /// address space as equal.
+ /// 5. If types are complex.
+ /// Then both Left and Right are to be expanded and their element types will
+ /// be checked with the same way. If we get Res != 0 on some stage, return it.
+ /// Otherwise return 0.
+ /// 6. For all other cases put llvm_unreachable.
+ int cmpType(Type *TyL, Type *TyR) const;
+
+ bool isEquivalentType(Type *Ty1, Type *Ty2) const {
+ return cmpType(Ty1, Ty2) == 0;
+ }
+
+ int cmpNumbers(uint64_t L, uint64_t R) const;
// The two functions undergoing comparison.
const Function *F1, *F2;
- const DataLayout *TD;
+ const DataLayout *DL;
DenseMap<const Value *, const Value *> id_map;
DenseSet<const Value *> seen_values;
}
-// Any two pointers in the same address space are equivalent, intptr_t and
-// pointers are equivalent. Otherwise, standard type equivalence rules apply.
-bool FunctionComparator::isEquivalentType(Type *Ty1, Type *Ty2) const {
- if (Ty1 == Ty2)
- return true;
- if (Ty1->getTypeID() != Ty2->getTypeID()) {
- if (TD) {
- LLVMContext &Ctx = Ty1->getContext();
- if (isa<PointerType>(Ty1) && Ty2 == TD->getIntPtrType(Ctx)) return true;
- if (isa<PointerType>(Ty2) && Ty1 == TD->getIntPtrType(Ctx)) return true;
- }
- return false;
+int FunctionComparator::cmpNumbers(uint64_t L, uint64_t R) const {
+ if (L < R) return -1;
+ if (L > R) return 1;
+ return 0;
+}
+
+/// cmpType - compares two types,
+/// defines total ordering among the types set.
+/// See method declaration comments for more details.
+int FunctionComparator::cmpType(Type *TyL, Type *TyR) const {
+
+ PointerType *PTyL = dyn_cast<PointerType>(TyL);
+ PointerType *PTyR = dyn_cast<PointerType>(TyR);
+
+ if (DL) {
+ if (PTyL && PTyL->getAddressSpace() == 0) TyL = DL->getIntPtrType(TyL);
+ if (PTyR && PTyR->getAddressSpace() == 0) TyR = DL->getIntPtrType(TyR);
}
- switch (Ty1->getTypeID()) {
+ if (TyL == TyR)
+ return 0;
+
+ if (int Res = cmpNumbers(TyL->getTypeID(), TyR->getTypeID()))
+ return Res;
+
+ switch (TyL->getTypeID()) {
default:
llvm_unreachable("Unknown type!");
// Fall through in Release mode.
case Type::IntegerTyID:
case Type::VectorTyID:
- // Ty1 == Ty2 would have returned true earlier.
- return false;
+ // TyL == TyR would have returned true earlier.
+ return cmpNumbers((uint64_t)TyL, (uint64_t)TyR);
case Type::VoidTyID:
case Type::FloatTyID:
case Type::PPC_FP128TyID:
case Type::LabelTyID:
case Type::MetadataTyID:
- return true;
+ return 0;
case Type::PointerTyID: {
- PointerType *PTy1 = cast<PointerType>(Ty1);
- PointerType *PTy2 = cast<PointerType>(Ty2);
- return PTy1->getAddressSpace() == PTy2->getAddressSpace();
+ assert(PTyL && PTyR && "Both types must be pointers here.");
+ return cmpNumbers(PTyL->getAddressSpace(), PTyR->getAddressSpace());
}
case Type::StructTyID: {
- StructType *STy1 = cast<StructType>(Ty1);
- StructType *STy2 = cast<StructType>(Ty2);
- if (STy1->getNumElements() != STy2->getNumElements())
- return false;
-
- if (STy1->isPacked() != STy2->isPacked())
- return false;
-
- for (unsigned i = 0, e = STy1->getNumElements(); i != e; ++i) {
- if (!isEquivalentType(STy1->getElementType(i), STy2->getElementType(i)))
- return false;
+ StructType *STyL = cast<StructType>(TyL);
+ StructType *STyR = cast<StructType>(TyR);
+ if (STyL->getNumElements() != STyR->getNumElements())
+ return cmpNumbers(STyL->getNumElements(), STyR->getNumElements());
+
+ if (STyL->isPacked() != STyR->isPacked())
+ return cmpNumbers(STyL->isPacked(), STyR->isPacked());
+
+ for (unsigned i = 0, e = STyL->getNumElements(); i != e; ++i) {
+ if (int Res = cmpType(STyL->getElementType(i),
+ STyR->getElementType(i)))
+ return Res;
}
- return true;
+ return 0;
}
case Type::FunctionTyID: {
- FunctionType *FTy1 = cast<FunctionType>(Ty1);
- FunctionType *FTy2 = cast<FunctionType>(Ty2);
- if (FTy1->getNumParams() != FTy2->getNumParams() ||
- FTy1->isVarArg() != FTy2->isVarArg())
- return false;
+ FunctionType *FTyL = cast<FunctionType>(TyL);
+ FunctionType *FTyR = cast<FunctionType>(TyR);
+ if (FTyL->getNumParams() != FTyR->getNumParams())
+ return cmpNumbers(FTyL->getNumParams(), FTyR->getNumParams());
- if (!isEquivalentType(FTy1->getReturnType(), FTy2->getReturnType()))
- return false;
+ if (FTyL->isVarArg() != FTyR->isVarArg())
+ return cmpNumbers(FTyL->isVarArg(), FTyR->isVarArg());
- for (unsigned i = 0, e = FTy1->getNumParams(); i != e; ++i) {
- if (!isEquivalentType(FTy1->getParamType(i), FTy2->getParamType(i)))
- return false;
+ if (int Res = cmpType(FTyL->getReturnType(), FTyR->getReturnType()))
+ return Res;
+
+ for (unsigned i = 0, e = FTyL->getNumParams(); i != e; ++i) {
+ if (int Res = cmpType(FTyL->getParamType(i), FTyR->getParamType(i)))
+ return Res;
}
- return true;
+ return 0;
}
case Type::ArrayTyID: {
- ArrayType *ATy1 = cast<ArrayType>(Ty1);
- ArrayType *ATy2 = cast<ArrayType>(Ty2);
- return ATy1->getNumElements() == ATy2->getNumElements() &&
- isEquivalentType(ATy1->getElementType(), ATy2->getElementType());
+ ArrayType *ATyL = cast<ArrayType>(TyL);
+ ArrayType *ATyR = cast<ArrayType>(TyR);
+ if (ATyL->getNumElements() != ATyR->getNumElements())
+ return cmpNumbers(ATyL->getNumElements(), ATyR->getNumElements());
+ return cmpType(ATyL->getElementType(), ATyR->getElementType());
}
}
}
FI->getSynchScope() == cast<FenceInst>(I2)->getSynchScope();
if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I1))
return CXI->isVolatile() == cast<AtomicCmpXchgInst>(I2)->isVolatile() &&
- CXI->getOrdering() == cast<AtomicCmpXchgInst>(I2)->getOrdering() &&
+ CXI->getSuccessOrdering() ==
+ cast<AtomicCmpXchgInst>(I2)->getSuccessOrdering() &&
+ CXI->getFailureOrdering() ==
+ cast<AtomicCmpXchgInst>(I2)->getFailureOrdering() &&
CXI->getSynchScope() == cast<AtomicCmpXchgInst>(I2)->getSynchScope();
if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I1))
return RMWI->getOperation() == cast<AtomicRMWInst>(I2)->getOperation() &&
// Determine whether two GEP operations perform the same underlying arithmetic.
bool FunctionComparator::isEquivalentGEP(const GEPOperator *GEP1,
const GEPOperator *GEP2) {
- // When we have target data, we can reduce the GEP down to the value in bytes
- // added to the address.
- unsigned BitWidth = TD ? TD->getPointerSizeInBits() : 1;
- APInt Offset1(BitWidth, 0), Offset2(BitWidth, 0);
- if (TD &&
- GEP1->accumulateConstantOffset(*TD, Offset1) &&
- GEP2->accumulateConstantOffset(*TD, Offset2)) {
- return Offset1 == Offset2;
+ unsigned AS = GEP1->getPointerAddressSpace();
+ if (AS != GEP2->getPointerAddressSpace())
+ return false;
+
+ if (DL) {
+ // When we have target data, we can reduce the GEP down to the value in bytes
+ // added to the address.
+ unsigned BitWidth = DL ? DL->getPointerSizeInBits(AS) : 1;
+ APInt Offset1(BitWidth, 0), Offset2(BitWidth, 0);
+ if (GEP1->accumulateConstantOffset(*DL, Offset1) &&
+ GEP2->accumulateConstantOffset(*DL, Offset2)) {
+ return Offset1 == Offset2;
+ }
}
if (GEP1->getPointerOperand()->getType() !=
initializeMergeFunctionsPass(*PassRegistry::getPassRegistry());
}
- bool runOnModule(Module &M);
+ bool runOnModule(Module &M) override;
private:
typedef DenseSet<ComparableFunction> FnSetType;
FnSetType FnSet;
/// DataLayout for more accurate GEP comparisons. May be NULL.
- DataLayout *TD;
+ const DataLayout *DL;
/// Whether or not the target supports global aliases.
bool HasGlobalAliases;
bool MergeFunctions::runOnModule(Module &M) {
bool Changed = false;
- TD = getAnalysisIfAvailable<DataLayout>();
+ DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
+ DL = DLP ? &DLP->getDataLayout() : 0;
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
if (!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
Function *F = cast<Function>(*I);
if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage() &&
!F->mayBeOverridden()) {
- ComparableFunction CF = ComparableFunction(F, TD);
+ ComparableFunction CF = ComparableFunction(F, DL);
Changed |= insert(CF);
}
}
Function *F = cast<Function>(*I);
if (!F->isDeclaration() && !F->hasAvailableExternallyLinkage() &&
F->mayBeOverridden()) {
- ComparableFunction CF = ComparableFunction(F, TD);
+ ComparableFunction CF = ComparableFunction(F, DL);
Changed |= insert(CF);
}
}
return false;
// One of these is a special "underlying pointer comparison only" object.
- if (LHS.getTD() == ComparableFunction::LookupOnly ||
- RHS.getTD() == ComparableFunction::LookupOnly)
+ if (LHS.getDataLayout() == ComparableFunction::LookupOnly ||
+ RHS.getDataLayout() == ComparableFunction::LookupOnly)
return false;
- assert(LHS.getTD() == RHS.getTD() &&
+ assert(LHS.getDataLayout() == RHS.getDataLayout() &&
"Comparing functions for different targets");
- return FunctionComparator(LHS.getTD(), LHS.getFunc(),
+ return FunctionComparator(LHS.getDataLayout(), LHS.getFunc(),
RHS.getFunc()).compare();
}
// Replace direct callers of Old with New.
void MergeFunctions::replaceDirectCallers(Function *Old, Function *New) {
Constant *BitcastNew = ConstantExpr::getBitCast(New, Old->getType());
- for (Value::use_iterator UI = Old->use_begin(), UE = Old->use_end();
- UI != UE;) {
- Value::use_iterator TheIter = UI;
+ for (auto UI = Old->use_begin(), UE = Old->use_end(); UI != UE;) {
+ Use *U = &*UI;
++UI;
- CallSite CS(*TheIter);
- if (CS && CS.isCallee(TheIter)) {
+ CallSite CS(U->getUser());
+ if (CS && CS.isCallee(U)) {
remove(CS.getInstruction()->getParent()->getParent());
- TheIter.getUse().set(BitcastNew);
+ U->set(BitcastNew);
}
}
}
writeThunk(F, G);
}
+// Helper for writeThunk,
+// Selects proper bitcast operation,
+// but a bit simpler then CastInst::getCastOpcode.
+static Value* createCast(IRBuilder<false> &Builder, Value *V, Type *DestTy) {
+ Type *SrcTy = V->getType();
+ if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
+ return Builder.CreateIntToPtr(V, DestTy);
+ else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
+ return Builder.CreatePtrToInt(V, DestTy);
+ else
+ return Builder.CreateBitCast(V, DestTy);
+}
+
// Replace G with a simple tail call to bitcast(F). Also replace direct uses
// of G with bitcast(F). Deletes G.
void MergeFunctions::writeThunk(Function *F, Function *G) {
FunctionType *FFTy = F->getFunctionType();
for (Function::arg_iterator AI = NewG->arg_begin(), AE = NewG->arg_end();
AI != AE; ++AI) {
- Args.push_back(Builder.CreateBitCast(AI, FFTy->getParamType(i)));
+ Args.push_back(createCast(Builder, (Value*)AI, FFTy->getParamType(i)));
++i;
}
if (NewG->getReturnType()->isVoidTy()) {
Builder.CreateRetVoid();
} else {
- Type *RetTy = NewG->getReturnType();
- if (CI->getType()->isIntegerTy() && RetTy->isPointerTy())
- Builder.CreateRet(Builder.CreateIntToPtr(CI, RetTy));
- else if (CI->getType()->isPointerTy() && RetTy->isIntegerTy())
- Builder.CreateRet(Builder.CreatePtrToInt(CI, RetTy));
- else
- Builder.CreateRet(Builder.CreateBitCast(CI, RetTy));
+ Builder.CreateRet(createCast(Builder, CI, NewG->getReturnType()));
}
NewG->copyAttributesFrom(G);
const ComparableFunction &OldF = *Result.first;
+ // Don't merge tiny functions, since it can just end up making the function
+ // larger.
+ // FIXME: Should still merge them if they are unnamed_addr and produce an
+ // alias.
+ if (NewF.getFunc()->size() == 1) {
+ if (NewF.getFunc()->front().size() <= 2) {
+ DEBUG(dbgs() << NewF.getFunc()->getName()
+ << " is to small to bother merging\n");
+ return false;
+ }
+ }
+
// Never thunk a strong function to a weak function.
assert(!OldF.getFunc()->mayBeOverridden() ||
NewF.getFunc()->mayBeOverridden());
Value *V = Worklist.back();
Worklist.pop_back();
- for (Value::use_iterator UI = V->use_begin(), UE = V->use_end();
- UI != UE; ++UI) {
- Use &U = UI.getUse();
- if (Instruction *I = dyn_cast<Instruction>(U.getUser())) {
+ for (User *U : V->users()) {
+ if (Instruction *I = dyn_cast<Instruction>(U)) {
remove(I->getParent()->getParent());
- } else if (isa<GlobalValue>(U.getUser())) {
+ } else if (isa<GlobalValue>(U)) {
// do nothing
- } else if (Constant *C = dyn_cast<Constant>(U.getUser())) {
- for (Value::use_iterator CUI = C->use_begin(), CUE = C->use_end();
- CUI != CUE; ++CUI)
- Worklist.push_back(*CUI);
+ } else if (Constant *C = dyn_cast<Constant>(U)) {
+ for (User *UU : C->users())
+ Worklist.push_back(UU);
}
}
}
projects / oota-llvm.git / blobdiff