Revert r164614 to appease the buildbots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164627 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chad Rosier 2012-09-25 19:57:20 +00:00
parent fe4a778f6e
commit 442ffc346f
3 changed files with 7 additions and 222 deletions

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@ -23,16 +23,6 @@ namespace llvm {
namespace llvm {
/// Generate code to calculate the remainder of two integers, replacing Rem
/// with the generated code. This currently generates code using the udiv
/// expansion, but future work includes generating more specialized code,
/// e.g. when more information about the operands are known. Currently only
/// implements 32bit scalar division (due to udiv's limitation), but future
/// work is removing this limitation.
///
/// @brief Replace Rem with generated code.
bool expandRemainder(BinaryOperator *Rem);
/// Generate code to divide two integers, replacing Div with the generated
/// code. This currently generates code similarly to compiler-rt's
/// implementations, but future work includes generating more specialized code

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@ -23,69 +23,11 @@
using namespace llvm;
/// Generate code to compute the remainder of two signed integers. Returns the
/// remainder, which will have the sign of the dividend. Builder's insert point
/// should be pointing where the caller wants code generated, e.g. at the srem
/// instruction. This will generate a urem in the process, and Builder's insert
/// point will be pointing at the uren (if present, i.e. not folded), ready to
/// be expanded if the user wishes
static Value *generateSignedRemainderCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
ConstantInt *ThirtyOne = Builder.getInt32(31);
// ; %dividend_sgn = ashr i32 %dividend, 31
// ; %divisor_sgn = ashr i32 %divisor, 31
// ; %dvd_xor = xor i32 %dividend, %dividend_sgn
// ; %dvs_xor = xor i32 %divisor, %divisor_sgn
// ; %u_dividend = sub i32 %dvd_xor, %dividend_sgn
// ; %u_divisor = sub i32 %dvs_xor, %divisor_sgn
// ; %urem = urem i32 %dividend, %divisor
// ; %xored = xor i32 %urem, %dividend_sgn
// ; %srem = sub i32 %xored, %dividend_sgn
Value *DividendSign = Builder.CreateAShr(Dividend, ThirtyOne);
Value *DivisorSign = Builder.CreateAShr(Divisor, ThirtyOne);
Value *DvdXor = Builder.CreateXor(Dividend, DividendSign);
Value *DvsXor = Builder.CreateXor(Divisor, DivisorSign);
Value *UDividend = Builder.CreateSub(DvdXor, DividendSign);
Value *UDivisor = Builder.CreateSub(DvsXor, DivisorSign);
Value *URem = Builder.CreateURem(UDividend, UDivisor);
Value *Xored = Builder.CreateXor(URem, DividendSign);
Value *SRem = Builder.CreateSub(Xored, DividendSign);
if (Instruction *URem = dyn_cast<Instruction>(URem))
Builder.SetInsertPoint(URem);
return SRem;
}
/// Generate code to compute the remainder of two unsigned integers. Returns the
/// remainder. Builder's insert point should be pointing where the caller wants
/// code generated, e.g. at the urem instruction. This will generate a udiv in
/// the process, and Builder's insert point will be pointing at the udiv (if
/// present, i.e. not folded), ready to be expanded if the user wishes
static Value *generatedUnsignedRemainderCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// Remainder = Dividend - Quotient*Divisor
// ; %quotient = udiv i32 %dividend, %divisor
// ; %product = mul i32 %divisor, %quotient
// ; %remainder = sub i32 %dividend, %product
Value *Quotient = Builder.CreateUDiv(Dividend, Divisor);
Value *Product = Builder.CreateMul(Divisor, Quotient);
Value *Remainder = Builder.CreateSub(Dividend, Product);
if (Instruction *UDiv = dyn_cast<Instruction>(Quotient))
Builder.SetInsertPoint(UDiv);
return Remainder;
}
/// Generate code to divide two signed integers. Returns the quotient, rounded
/// towards 0. Builder's insert point should be pointing where the caller wants
/// code generated, e.g. at the sdiv instruction. This will generate a udiv in
/// the process, and Builder's insert point will be pointing at the udiv (if
/// present, i.e. not folded), ready to be expanded if the user wishes.
/// towards 0. Builder's insert point should be pointing at the sdiv
/// instruction. This will generate a udiv in the process, and Builder's insert
/// point will be pointing at the udiv (if present, i.e. not folded), ready to
/// be expanded if the user wishes.
static Value *generateSignedDivisionCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// Implementation taken from compiler-rt's __divsi3
@ -120,8 +62,8 @@ static Value *generateSignedDivisionCode(Value *Dividend, Value *Divisor,
}
/// Generates code to divide two unsigned scalar 32-bit integers. Returns the
/// quotient, rounded towards 0. Builder's insert point should be pointing where
/// the caller wants code generated, e.g. at the udiv instruction.
/// quotient, rounded towards 0. Builder's insert point should be pointing at
/// the udiv instruction.
static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// The basic algorithm can be found in the compiler-rt project's
@ -323,56 +265,6 @@ static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,
return Q_5;
}
/// Generate code to calculate the remainder of two integers, replacing Rem with
/// the generated code. This currently generates code using the udiv expansion,
/// but future work includes generating more specialized code, e.g. when more
/// information about the operands are known. Currently only implements 32bit
/// scalar division (due to udiv's limitation), but future work is removing this
/// limitation.
///
/// @brief Replace Rem with generated code.
bool llvm::expandRemainder(BinaryOperator *Rem) {
assert((Rem->getOpcode() == Instruction::SRem ||
Rem->getOpcode() == Instruction::URem) &&
"Trying to expand remainder from a non-remainder function");
IRBuilder<> Builder(Rem);
// First prepare the sign if it's a signed remainder
if (Rem->getOpcode() == Instruction::SRem) {
Value *Remainder = generateSignedRemainderCode(Rem->getOperand(0),
Rem->getOperand(1), Builder);
Rem->replaceAllUsesWith(Remainder);
Rem->dropAllReferences();
Rem->eraseFromParent();
// If we didn't actually generate a udiv instruction, we're done
BinaryOperator *BO = dyn_cast<BinaryOperator>(Builder.GetInsertPoint());
if (!BO || BO->getOpcode() != Instruction::URem)
return true;
Rem = BO;
}
Value *Remainder = generatedUnsignedRemainderCode(Rem->getOperand(0),
Rem->getOperand(1),
Builder);
Rem->replaceAllUsesWith(Remainder);
Rem->dropAllReferences();
Rem->eraseFromParent();
// Expand the udiv
if (BinaryOperator *UDiv = dyn_cast<BinaryOperator>(Builder.GetInsertPoint())) {
assert(UDiv->getOpcode() == Instruction::UDiv && "Non-udiv in expansion?");
expandDivision(UDiv);
}
return true;
}
/// Generate code to divide two integers, replacing Div with the generated
/// code. This currently generates code similarly to compiler-rt's
/// implementations, but future work includes generating more specialized code
@ -395,7 +287,7 @@ bool llvm::expandDivision(BinaryOperator *Div) {
if (Div->getOpcode() == Instruction::SDiv) {
// Lower the code to unsigned division, and reset Div to point to the udiv.
Value *Quotient = generateSignedDivisionCode(Div->getOperand(0),
Div->getOperand(1), Builder);
Div->getOperand(1), Builder);
Div->replaceAllUsesWith(Quotient);
Div->dropAllReferences();
Div->eraseFromParent();

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@ -51,101 +51,4 @@ TEST(IntegerDivision, SDiv) {
Builder.SetInsertPoint(BB->end());
}
TEST(IntegerDivision, UDiv) {
LLVMContext &C(getGlobalContext());
Module M("test division", C);
IRBuilder<> Builder(C);
SmallVector<Type*, 2> ArgTys(2, Builder.getInt32Ty());
Function *F = Function::Create(FunctionType::get(Builder.getInt32Ty(),
ArgTys, false),
GlobalValue::ExternalLinkage, "F", &M);
assert(F->getArgumentList().size() == 2);
BasicBlock *BB = BasicBlock::Create(C, "", F);
Builder.SetInsertPoint(BB);
Function::arg_iterator AI = F->arg_begin();
Value *A = AI++;
Value *B = AI++;
Value *Div = Builder.CreateUDiv(A, B);
EXPECT_TRUE(BB->front().getOpcode() == Instruction::UDiv);
Value *Ret = Builder.CreateRet(Div);
expandDivision(cast<BinaryOperator>(Div));
EXPECT_TRUE(BB->front().getOpcode() == Instruction::ICmp);
Instruction* Quotient = dyn_cast<Instruction>(cast<User>(Ret)->getOperand(0));
EXPECT_TRUE(Quotient && Quotient->getOpcode() == Instruction::PHI);
Builder.SetInsertPoint(BB->end());
}
TEST(IntegerDivision, SRem) {
LLVMContext &C(getGlobalContext());
Module M("test remainder", C);
IRBuilder<> Builder(C);
SmallVector<Type*, 2> ArgTys(2, Builder.getInt32Ty());
Function *F = Function::Create(FunctionType::get(Builder.getInt32Ty(),
ArgTys, false),
GlobalValue::ExternalLinkage, "F", &M);
assert(F->getArgumentList().size() == 2);
BasicBlock *BB = BasicBlock::Create(C, "", F);
Builder.SetInsertPoint(BB);
Function::arg_iterator AI = F->arg_begin();
Value *A = AI++;
Value *B = AI++;
Value *Rem = Builder.CreateSRem(A, B);
EXPECT_TRUE(BB->front().getOpcode() == Instruction::SRem);
Value *Ret = Builder.CreateRet(Rem);
expandRemainder(cast<BinaryOperator>(Rem));
EXPECT_TRUE(BB->front().getOpcode() == Instruction::AShr);
Instruction* Remainder = dyn_cast<Instruction>(cast<User>(Ret)->getOperand(0));
EXPECT_TRUE(Remainder && Remainder->getOpcode() == Instruction::Sub);
Builder.SetInsertPoint(BB->end());
}
TEST(IntegerDivision, URem) {
LLVMContext &C(getGlobalContext());
Module M("test remainder", C);
IRBuilder<> Builder(C);
SmallVector<Type*, 2> ArgTys(2, Builder.getInt32Ty());
Function *F = Function::Create(FunctionType::get(Builder.getInt32Ty(),
ArgTys, false),
GlobalValue::ExternalLinkage, "F", &M);
assert(F->getArgumentList().size() == 2);
BasicBlock *BB = BasicBlock::Create(C, "", F);
Builder.SetInsertPoint(BB);
Function::arg_iterator AI = F->arg_begin();
Value *A = AI++;
Value *B = AI++;
Value *Rem = Builder.CreateURem(A, B);
EXPECT_TRUE(BB->front().getOpcode() == Instruction::URem);
Value *Ret = Builder.CreateRet(Rem);
expandRemainder(cast<BinaryOperator>(Rem));
EXPECT_TRUE(BB->front().getOpcode() == Instruction::ICmp);
Instruction* Remainder = dyn_cast<Instruction>(cast<User>(Ret)->getOperand(0));
EXPECT_TRUE(Remainder && Remainder->getOpcode() == Instruction::Sub);
Builder.SetInsertPoint(BB->end());
}
}