Func == LibFunc::llabs || Func == LibFunc::strlen;
}
-/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
-/// value is equal or not-equal to zero.
+/// Return true if it only matters that the value is equal or not-equal to zero.
static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
for (User *U : V->users()) {
if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
return true;
}
-/// isOnlyUsedInEqualityComparison - Return true if it is only used in equality
-/// comparisons with With.
+/// Return true if it is only used in equality comparisons with With.
static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) {
for (User *U : V->users()) {
if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
!FT->getParamType(2)->isIntegerTy())
return nullptr;
- // Extract some information from the instruction
+ // Extract some information from the instruction.
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
uint64_t Len;
- // We don't do anything if length is not constant
+ // We don't do anything if length is not constant.
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
Len = LengthArg->getZExtValue();
else
if (SrcLen == 0 || Len == 0)
return Dst;
- // We don't optimize this case
+ // We don't optimize this case.
if (Len < SrcLen)
return nullptr;
// strncat(x, s, c) -> strcat(x, s)
- // s is constant so the strcat can be optimized further
+ // s is constant so the strcat can be optimized further.
return emitStrLenMemCpy(Src, Dst, SrcLen, B);
}
StringRef Str;
if (!getConstantStringInfo(SrcStr, Str)) {
if (CharC->isZero()) // strchr(p, 0) -> p + strlen(p)
- return B.CreateGEP(B.getInt8Ty(), SrcStr, EmitStrLen(SrcStr, B, DL, TLI), "strchr");
+ return B.CreateGEP(B.getInt8Ty(), SrcStr, EmitStrLen(SrcStr, B, DL, TLI),
+ "strchr");
return nullptr;
}
Type *PT = Callee->getFunctionType()->getParamType(0);
Value *LenV = ConstantInt::get(DL.getIntPtrType(PT), Len);
- Value *DstEnd =
- B.CreateGEP(B.getInt8Ty(), Dst, ConstantInt::get(DL.getIntPtrType(PT), Len - 1));
+ Value *DstEnd = B.CreateGEP(B.getInt8Ty(), Dst,
+ ConstantInt::get(DL.getIntPtrType(PT), Len - 1));
// We have enough information to now generate the memcpy call to do the
// copy for us. Make a memcpy to copy the nul byte with align = 1.
if (I == StringRef::npos) // No match.
return Constant::getNullValue(CI->getType());
- return B.CreateGEP(B.getInt8Ty(), CI->getArgOperand(0), B.getInt64(I), "strpbrk");
+ return B.CreateGEP(B.getInt8Ty(), CI->getArgOperand(0), B.getInt64(I),
+ "strpbrk");
}
// strpbrk(s, "a") -> strchr(s, 'a')
Type *RHSPtrTy =
IntType->getPointerTo(RHS->getType()->getPointerAddressSpace());
- Value *LHSV = B.CreateLoad(B.CreateBitCast(LHS, LHSPtrTy, "lhsc"), "lhsv");
- Value *RHSV = B.CreateLoad(B.CreateBitCast(RHS, RHSPtrTy, "rhsc"), "rhsv");
+ Value *LHSV =
+ B.CreateLoad(B.CreateBitCast(LHS, LHSPtrTy, "lhsc"), "lhsv");
+ Value *RHSV =
+ B.CreateLoad(B.CreateBitCast(RHS, RHSPtrTy, "rhsc"), "rhsv");
return B.CreateZExt(B.CreateICmpNE(LHSV, RHSV), CI->getType(), "memcmp");
}
Value *V = valueHasFloatPrecision(CI->getArgOperand(0));
if (V == nullptr)
return nullptr;
+
+ // Propagate fast-math flags from the existing call to the new call.
+ IRBuilder<>::FastMathFlagGuard Guard(B);
+ B.SetFastMathFlags(CI->getFastMathFlags());
// floor((double)floatval) -> (double)floorf(floatval)
if (Callee->isIntrinsic()) {
- Module *M = CI->getParent()->getParent()->getParent();
+ Module *M = CI->getModule();
Intrinsic::ID IID = Callee->getIntrinsicID();
Function *F = Intrinsic::getDeclaration(M, IID, B.getFloatTy());
V = B.CreateCall(F, V);
return Ret;
}
+static Value *getPow(Value *InnerChain[33], unsigned Exp, IRBuilder<> &B) {
+ // Multiplications calculated using Addition Chains.
+ // Refer: http://wwwhomes.uni-bielefeld.de/achim/addition_chain.html
+
+ assert(Exp != 0 && "Incorrect exponent 0 not handled");
+
+ if (InnerChain[Exp])
+ return InnerChain[Exp];
+
+ static const unsigned AddChain[33][2] = {
+ {0, 0}, // Unused.
+ {0, 0}, // Unused (base case = pow1).
+ {1, 1}, // Unused (pre-computed).
+ {1, 2}, {2, 2}, {2, 3}, {3, 3}, {2, 5}, {4, 4},
+ {1, 8}, {5, 5}, {1, 10}, {6, 6}, {4, 9}, {7, 7},
+ {3, 12}, {8, 8}, {8, 9}, {2, 16}, {1, 18}, {10, 10},
+ {6, 15}, {11, 11}, {3, 20}, {12, 12}, {8, 17}, {13, 13},
+ {3, 24}, {14, 14}, {4, 25}, {15, 15}, {3, 28}, {16, 16},
+ };
+
+ InnerChain[Exp] = B.CreateFMul(getPow(InnerChain, AddChain[Exp][0], B),
+ getPow(InnerChain, AddChain[Exp][1], B));
+ return InnerChain[Exp];
+}
+
Value *LibCallSimplifier::optimizePow(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Value *Ret = nullptr;
Callee->getAttributes());
}
- bool unsafeFPMath = canUseUnsafeFPMath(CI->getParent()->getParent());
+ bool UnsafeFPMath = canUseUnsafeFPMath(CI->getParent()->getParent());
// pow(exp(x), y) -> exp(x*y)
// pow(exp2(x), y) -> exp2(x * y)
// underflow behavior quite dramatically.
// Example: x = 1000, y = 0.001.
// pow(exp(x), y) = pow(inf, 0.001) = inf, whereas exp(x*y) = exp(1).
- if (unsafeFPMath) {
+ if (UnsafeFPMath) {
if (auto *OpC = dyn_cast<CallInst>(Op1)) {
IRBuilder<>::FastMathFlagGuard Guard(B);
FastMathFlags FMF;
LibFunc::fabsl)) {
// In -ffast-math, pow(x, 0.5) -> sqrt(x).
- if (unsafeFPMath)
+ if (UnsafeFPMath)
return EmitUnaryFloatFnCall(Op1, TLI->getName(LibFunc::sqrt), B,
Callee->getAttributes());
return B.CreateFMul(Op1, Op1, "pow2");
if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0), Op1, "powrecip");
+
+ // In -ffast-math, generate repeated fmul instead of generating pow(x, n).
+ if (UnsafeFPMath) {
+ APFloat V = abs(Op2C->getValueAPF());
+ // We limit to a max of 7 fmul(s). Thus max exponent is 32.
+ // This transformation applies to integer exponents only.
+ if (V.compare(APFloat(V.getSemantics(), 32.0)) == APFloat::cmpGreaterThan ||
+ !V.isInteger())
+ return nullptr;
+
+ // We will memoize intermediate products of the Addition Chain.
+ Value *InnerChain[33] = {nullptr};
+ InnerChain[1] = Op1;
+ InnerChain[2] = B.CreateFMul(Op1, Op1);
+
+ // We cannot readily convert a non-double type (like float) to a double.
+ // So we first convert V to something which could be converted to double.
+ bool ignored;
+ V.convert(APFloat::IEEEdouble, APFloat::rmTowardZero, &ignored);
+ Value *FMul = getPow(InnerChain, V.convertToDouble(), B);
+ // For negative exponents simply compute the reciprocal.
+ if (Op2C->isNegative())
+ FMul = B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0), FMul);
+ return FMul;
+ }
+
return nullptr;
}
LibFunc::Func Func;
Function *F = OpC->getCalledFunction();
- StringRef FuncName = F->getName();
- if ((TLI->getLibFunc(FuncName, Func) && TLI->has(Func) &&
- Func == LibFunc::pow) || F->getIntrinsicID() == Intrinsic::pow)
+ if (F && ((TLI->getLibFunc(F->getName(), Func) && TLI->has(Func) &&
+ Func == LibFunc::pow) || F->getIntrinsicID() == Intrinsic::pow))
return B.CreateFMul(OpC->getArgOperand(1),
EmitUnaryFloatFnCall(OpC->getOperand(0), Callee->getName(), B,
Callee->getAttributes()), "mul");
+
+ // log(exp2(y)) -> y*log(2)
+ if (F && Name == "log" && TLI->getLibFunc(F->getName(), Func) &&
+ TLI->has(Func) && Func == LibFunc::exp2)
+ return B.CreateFMul(
+ OpC->getArgOperand(0),
+ EmitUnaryFloatFnCall(ConstantFP::get(CI->getType(), 2.0),
+ Callee->getName(), B, Callee->getAttributes()),
+ "logmul");
return Ret;
}
// log, logf, logl:
// * log(exp(x)) -> x
// * log(exp(y)) -> y*log(e)
-// * log(exp2(y)) -> y*log(2)
// * log(exp10(y)) -> y*log(10)
// * log(sqrt(x)) -> 0.5*log(x)
//
return false;
}
-Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI, IRBuilder<> &B) {
+Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI,
+ IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy_chk))
return nullptr;
}
-Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI, IRBuilder<> &B) {
+Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI,
+ IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove_chk))
return nullptr;
}
-Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI, IRBuilder<> &B) {
+Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI,
+ IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset_chk))
projects / oota-llvm.git / blobdiff