mirror of
https://github.com/RPCS3/llvm.git
synced 2024-12-22 12:08:33 +00:00
Revert "[Reassociate] Canonicalize negative constants out of expressions."
This reverts commit r221171. It performs this invalid transformation: - %div.i = urem i64 -1, %add - %sub.i = sub i64 -2, %div.i + %div.i = urem i64 1, %add + %sub.i1 = add i64 %div.i, -2 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221317 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
parent
4ad0654bb4
commit
11e6e005b7
@ -193,8 +193,9 @@ namespace {
|
||||
Value *OptimizeMul(BinaryOperator *I, SmallVectorImpl<ValueEntry> &Ops);
|
||||
Value *RemoveFactorFromExpression(Value *V, Value *Factor);
|
||||
void EraseInst(Instruction *I);
|
||||
void optimizeFAddNegExpr(ConstantFP *ConstOperand, Instruction *I,
|
||||
int OperandNr);
|
||||
void OptimizeInst(Instruction *I);
|
||||
Instruction *canonicalizeNegConstExpr(Instruction *I);
|
||||
};
|
||||
}
|
||||
|
||||
@ -1929,105 +1930,31 @@ void Reassociate::EraseInst(Instruction *I) {
|
||||
}
|
||||
}
|
||||
|
||||
// Canonicalize expressions of the following form:
|
||||
// x + (-Constant * y) -> x - (Constant * y)
|
||||
// x - (-Constant * y) -> x + (Constant * y)
|
||||
Instruction *Reassociate::canonicalizeNegConstExpr(Instruction *I) {
|
||||
if (!I->hasOneUse() || I->getType()->isVectorTy())
|
||||
return nullptr;
|
||||
|
||||
// Must have at least one constant operand.
|
||||
Constant *C0 = dyn_cast<Constant>(I->getOperand(0));
|
||||
Constant *C1 = dyn_cast<Constant>(I->getOperand(1));
|
||||
if (!C0 && !C1)
|
||||
return nullptr;
|
||||
|
||||
// Must be a negative ConstantInt or ConstantFP.
|
||||
Constant *C = C0 ? C0 : C1;
|
||||
unsigned ConstIdx = C0 ? 0 : 1;
|
||||
if (auto *CI = dyn_cast<ConstantInt>(C)) {
|
||||
if (!CI->isNegative())
|
||||
return nullptr;
|
||||
} else if (auto *CF = dyn_cast<ConstantFP>(C)) {
|
||||
if (!CF->isNegative())
|
||||
return nullptr;
|
||||
} else
|
||||
return nullptr;
|
||||
|
||||
// User must be a binary operator with one or more uses.
|
||||
Instruction *User = I->user_back();
|
||||
if (!isa<BinaryOperator>(User) || !User->getNumUses())
|
||||
return nullptr;
|
||||
|
||||
// Must be a binary operator with higher precedence that add/sub.
|
||||
switch(I->getOpcode()) {
|
||||
default:
|
||||
return nullptr;
|
||||
case Instruction::Mul:
|
||||
case Instruction::FMul:
|
||||
case Instruction::UDiv:
|
||||
case Instruction::SDiv:
|
||||
case Instruction::FDiv:
|
||||
case Instruction::URem:
|
||||
case Instruction::SRem:
|
||||
case Instruction::FRem:
|
||||
break;
|
||||
}
|
||||
|
||||
unsigned UserOpcode = User->getOpcode();
|
||||
if (UserOpcode != Instruction::Add && UserOpcode != Instruction::FAdd &&
|
||||
UserOpcode != Instruction::Sub && UserOpcode != Instruction::FSub)
|
||||
return nullptr;
|
||||
|
||||
// Subtraction is not commutative. Explicitly, the following transform is
|
||||
// not valid: (-Constant * y) - x -> x + (Constant * y)
|
||||
if (!User->isCommutative() && User->getOperand(1) != I)
|
||||
return nullptr;
|
||||
|
||||
void Reassociate::optimizeFAddNegExpr(ConstantFP *ConstOperand, Instruction *I,
|
||||
int OperandNr) {
|
||||
// Change the sign of the constant.
|
||||
if (ConstantInt *CI = dyn_cast<ConstantInt>(C))
|
||||
I->setOperand(ConstIdx, ConstantInt::get(CI->getContext(), -CI->getValue()));
|
||||
else {
|
||||
ConstantFP *CF = cast<ConstantFP>(C);
|
||||
APFloat Val = CF->getValueAPF();
|
||||
Val.changeSign();
|
||||
I->setOperand(ConstIdx, ConstantFP::get(CF->getContext(), Val));
|
||||
}
|
||||
APFloat Val = ConstOperand->getValueAPF();
|
||||
Val.changeSign();
|
||||
I->setOperand(0, ConstantFP::get(ConstOperand->getContext(), Val));
|
||||
|
||||
// Canonicalize I to RHS to simplify the next bit of logic. E.g.,
|
||||
// ((-Const*y) + x) -> (x + (-Const*y)).
|
||||
if (User->getOperand(0) == I && User->isCommutative())
|
||||
cast<BinaryOperator>(User)->swapOperands();
|
||||
assert(I->hasOneUse() && "Only a single use can be replaced.");
|
||||
Instruction *Parent = I->user_back();
|
||||
|
||||
Value *Op0 = User->getOperand(0);
|
||||
Value *Op1 = User->getOperand(1);
|
||||
BinaryOperator *NI;
|
||||
switch(UserOpcode) {
|
||||
default:
|
||||
llvm_unreachable("Unexpected Opcode!");
|
||||
case Instruction::Add:
|
||||
NI = BinaryOperator::CreateSub(Op0, Op1);
|
||||
break;
|
||||
case Instruction::Sub:
|
||||
NI = BinaryOperator::CreateAdd(Op0, Op1);
|
||||
break;
|
||||
case Instruction::FAdd:
|
||||
NI = BinaryOperator::CreateFSub(Op0, Op1);
|
||||
NI->setFastMathFlags(cast<FPMathOperator>(User)->getFastMathFlags());
|
||||
break;
|
||||
case Instruction::FSub:
|
||||
NI = BinaryOperator::CreateFAdd(Op0, Op1);
|
||||
NI->setFastMathFlags(cast<FPMathOperator>(User)->getFastMathFlags());
|
||||
break;
|
||||
}
|
||||
Value *OtherOperand = Parent->getOperand(1 - OperandNr);
|
||||
|
||||
NI->insertBefore(User);
|
||||
NI->setName(User->getName());
|
||||
User->replaceAllUsesWith(NI);
|
||||
unsigned Opcode = Parent->getOpcode();
|
||||
assert(Opcode == Instruction::FAdd ||
|
||||
(Opcode == Instruction::FSub && Parent->getOperand(1) == I));
|
||||
|
||||
BinaryOperator *NI = Opcode == Instruction::FAdd
|
||||
? BinaryOperator::CreateFSub(OtherOperand, I)
|
||||
: BinaryOperator::CreateFAdd(OtherOperand, I);
|
||||
NI->setFastMathFlags(cast<FPMathOperator>(Parent)->getFastMathFlags());
|
||||
NI->insertBefore(Parent);
|
||||
NI->setName(Parent->getName() + ".repl");
|
||||
Parent->replaceAllUsesWith(NI);
|
||||
NI->setDebugLoc(I->getDebugLoc());
|
||||
RedoInsts.insert(I);
|
||||
MadeChange = true;
|
||||
return NI;
|
||||
}
|
||||
|
||||
/// OptimizeInst - Inspect and optimize the given instruction. Note that erasing
|
||||
@ -2050,10 +1977,6 @@ void Reassociate::OptimizeInst(Instruction *I) {
|
||||
I = NI;
|
||||
}
|
||||
|
||||
// Canonicalize negative constants out of expressions.
|
||||
if (Instruction *Res = canonicalizeNegConstExpr(I))
|
||||
I = Res;
|
||||
|
||||
// Commute floating point binary operators, to canonicalize the order of their
|
||||
// operands. This can potentially expose more CSE opportunities, and makes
|
||||
// writing other transformations simpler.
|
||||
@ -2074,6 +1997,24 @@ void Reassociate::OptimizeInst(Instruction *I) {
|
||||
}
|
||||
}
|
||||
|
||||
// Reassociate: x + -ConstantFP * y -> x - ConstantFP * y
|
||||
// The FMul can also be an FDiv, and FAdd can be a FSub.
|
||||
if (Opcode == Instruction::FMul || Opcode == Instruction::FDiv) {
|
||||
if (ConstantFP *LHSConst = dyn_cast<ConstantFP>(I->getOperand(0))) {
|
||||
if (LHSConst->isNegative() && I->hasOneUse()) {
|
||||
Instruction *Parent = I->user_back();
|
||||
if (Parent->getOpcode() == Instruction::FAdd) {
|
||||
if (Parent->getOperand(0) == I)
|
||||
optimizeFAddNegExpr(LHSConst, I, 0);
|
||||
else if (Parent->getOperand(1) == I)
|
||||
optimizeFAddNegExpr(LHSConst, I, 1);
|
||||
} else if (Parent->getOpcode() == Instruction::FSub)
|
||||
if (Parent->getOperand(1) == I)
|
||||
optimizeFAddNegExpr(LHSConst, I, 1);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// FIXME: We should commute vector instructions as well. However, this
|
||||
// requires further analysis to determine the effect on later passes.
|
||||
|
||||
|
@ -203,7 +203,7 @@ define i32 @test14(i32 %X1, i32 %X2) {
|
||||
|
||||
; CHECK-LABEL: @test14
|
||||
; CHECK-NEXT: sub i32 %X1, %X2
|
||||
; CHECK-NEXT: mul i32 %B2, 47
|
||||
; CHECK-NEXT: mul i32 %tmp, 47
|
||||
; CHECK-NEXT: ret i32
|
||||
}
|
||||
|
||||
|
@ -1,235 +0,0 @@
|
||||
; RUN: opt -reassociate -gvn -S < %s | FileCheck %s
|
||||
|
||||
; (x + 0.1234 * y) * (x + -0.1234 * y) -> (x + 0.1234 * y) * (x - 0.1234 * y)
|
||||
define double @test1(double %x, double %y) {
|
||||
; CHECK-LABEL: @test1
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %mul
|
||||
; CHECK-NEXT: fsub double %x, %mul
|
||||
; CHECK-NEXT: fmul double %add{{.*}}, %add{{.*}}
|
||||
; CHECK-NEXT: ret double %mul
|
||||
|
||||
%mul = fmul double 1.234000e-01, %y
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double -1.234000e-01, %y
|
||||
%add2 = fadd double %mul1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + -0.1234 * y) * (x + -0.1234 * y) -> (x - 0.1234 * y) * (x - 0.1234 * y)
|
||||
define double @test2(double %x, double %y) {
|
||||
; CHECK-LABEL: @test2
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %x, %mul
|
||||
; CHECK-NEXT: fmul double %add{{.*}}, %add{{.*}}
|
||||
; CHECK-NEXT: ret double %mul
|
||||
|
||||
%mul = fmul double %y, -1.234000e-01
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double %y, -1.234000e-01
|
||||
%add2 = fadd double %mul1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + 0.1234 / y) * (x + -0.1234 / y) -> (x + 0.1234 / y) * (x - 0.1234 / y)
|
||||
define double @test3(double %x, double %y) {
|
||||
; CHECK-LABEL: @test3
|
||||
; CHECK-NEXT: fdiv double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %div
|
||||
; CHECK-NEXT: fsub double %x, %div
|
||||
; CHECK-NEXT: fmul double %add{{.*}}, %add{{.*}}
|
||||
; CHECK-NEXT: ret double
|
||||
|
||||
%div = fdiv double 1.234000e-01, %y
|
||||
%add = fadd double %div, %x
|
||||
%div1 = fdiv double -1.234000e-01, %y
|
||||
%add2 = fadd double %div1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + 0.1234 * y) * (x - -0.1234 * y) -> (x + 0.1234 * y) * (x + 0.1234 * y)
|
||||
define double @test4(double %x, double %y) {
|
||||
; CHECK-LABEL: @test4
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %mul
|
||||
; CHECK-NEXT: fmul double %add{{.*}}, %add{{.*}}
|
||||
; CHECK-NEXT: ret double
|
||||
|
||||
%mul = fmul double %y, 1.234000e-01
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double %y, -1.234000e-01
|
||||
%add2 = fsub double %x, %mul1
|
||||
%mul3 = fmul double %add, %add2
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; Canonicalize (x - -1234 * y)
|
||||
define i64 @test5(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test5
|
||||
; CHECK-NEXT: mul i64 %y, 1234
|
||||
; CHECK-NEXT: add i64 %mul, %x
|
||||
; CHECK-NEXT: ret i64 %sub
|
||||
|
||||
%mul = mul i64 %y, -1234
|
||||
%sub = sub i64 %x, %mul
|
||||
ret i64 %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x - -0.1234 * y)
|
||||
define double @test6(double %x, double %y) {
|
||||
; CHECK-LABEL: @test6
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %mul
|
||||
; CHECK-NEXT: ret double
|
||||
|
||||
%mul = fmul double -1.234000e-01, %y
|
||||
%sub = fsub double %x, %mul
|
||||
ret double %sub
|
||||
}
|
||||
|
||||
; Don't modify (-0.1234 * y - x)
|
||||
define double @test7(double %x, double %y) {
|
||||
; CHECK-LABEL: @test7
|
||||
; CHECK-NEXT: fmul double -1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %mul, %x
|
||||
; CHECK-NEXT: ret double %sub
|
||||
|
||||
%mul = fmul double -1.234000e-01, %y
|
||||
%sub = fsub double %mul, %x
|
||||
ret double %sub
|
||||
}
|
||||
|
||||
; Canonicalize (-0.1234 * y + x) -> (x - 0.1234 * y)
|
||||
define double @test8(double %x, double %y) {
|
||||
; CHECK-LABEL: @test8
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %x, %mul
|
||||
; CHECK-NEXT: ret double %add
|
||||
|
||||
%mul = fmul double -1.234000e-01, %y
|
||||
%add = fadd double %mul, %x
|
||||
ret double %add
|
||||
}
|
||||
|
||||
; Canonicalize (y * -0.1234 + x) -> (x - 0.1234 * y)
|
||||
define double @test9(double %x, double %y) {
|
||||
; CHECK-LABEL: @test9
|
||||
; CHECK-NEXT: fmul double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %x, %mul
|
||||
; CHECK-NEXT: ret double %add
|
||||
|
||||
%mul = fmul double %y, -1.234000e-01
|
||||
%add = fadd double %mul, %x
|
||||
ret double %add
|
||||
}
|
||||
|
||||
; Canonicalize (x - -1234 udiv y)
|
||||
define i64 @test10(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test10
|
||||
; CHECK-NEXT: udiv i64 1234, %y
|
||||
; CHECK-NEXT: add i64 %div, %x
|
||||
; CHECK-NEXT: ret i64 %sub
|
||||
|
||||
%div = udiv i64 -1234, %y
|
||||
%sub = sub i64 %x, %div
|
||||
ret i64 %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x - -1234 sdiv y)
|
||||
define i64 @test11(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test11
|
||||
; CHECK-NEXT: sdiv i64 1234, %y
|
||||
; CHECK-NEXT: add i64 %div, %x
|
||||
; CHECK-NEXT: ret i64 %sub
|
||||
|
||||
%div = sdiv i64 -1234, %y
|
||||
%sub = sub i64 %x, %div
|
||||
ret i64 %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x - -0.1234 / y)
|
||||
define double @test12(double %x, double %y) {
|
||||
; CHECK-LABEL: @test12
|
||||
; CHECK-NEXT: fdiv double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %div
|
||||
; CHECK-NEXT: ret double %sub
|
||||
|
||||
%div = fdiv double -1.234000e-01, %y
|
||||
%sub = fsub double %x, %div
|
||||
ret double %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x - -0.1234 urem y)
|
||||
define i64 @test13(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test13
|
||||
; CHECK-NEXT: urem i64 1234, %y
|
||||
; CHECK-NEXT: add i64 %urem, %x
|
||||
; CHECK-NEXT: ret i64 %sub
|
||||
|
||||
%urem = urem i64 -1234, %y
|
||||
%sub = sub i64 %x, %urem
|
||||
ret i64 %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x + -0.1234 srem y)
|
||||
define i64 @test14(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test14
|
||||
; CHECK-NEXT: srem i64 1234, %y
|
||||
; CHECK-NEXT: sub i64 %x, %srem
|
||||
; CHECK-NEXT: ret i64 %add
|
||||
|
||||
%srem = srem i64 -1234, %y
|
||||
%add = add i64 %x, %srem
|
||||
ret i64 %add
|
||||
}
|
||||
|
||||
; Don't modify (-0.1234 srem y - x)
|
||||
define i64 @test15(i64 %x, i64 %y) {
|
||||
; CHECK-LABEL: @test15
|
||||
; CHECK-NEXT: %srem = srem i64 -1234, %y
|
||||
; CHECK-NEXT: %sub = sub i64 %srem, %x
|
||||
; CHECK-NEXT: ret i64 %sub
|
||||
|
||||
%srem = srem i64 -1234, %y
|
||||
%sub = sub i64 %srem, %x
|
||||
ret i64 %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x - -0.1234 frem y)
|
||||
define double @test16(double %x, double %y) {
|
||||
; CHECK-LABEL: @test16
|
||||
; CHECK-NEXT: frem double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fadd double %x, %rem
|
||||
; CHECK-NEXT: ret double %sub
|
||||
|
||||
%rem = frem double -1.234000e-01, %y
|
||||
%sub = fsub double %x, %rem
|
||||
ret double %sub
|
||||
}
|
||||
|
||||
; Canonicalize (x + -0.1234 frem y)
|
||||
define double @test17(double %x, double %y) {
|
||||
; CHECK-LABEL: @test17
|
||||
; CHECK-NEXT: frem double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %x, %rem
|
||||
; CHECK-NEXT: ret double %add
|
||||
|
||||
%rem = frem double -1.234000e-01, %y
|
||||
%add = fadd double %x, %rem
|
||||
ret double %add
|
||||
}
|
||||
|
||||
; Canonicalize (-0.1234 frem y + x) -> (x - 0.1234 frem y)
|
||||
define double @test18(double %x, double %y) {
|
||||
; CHECK-LABEL: @test18
|
||||
; CHECK-NEXT: frem double 1.234000e-01, %y
|
||||
; CHECK-NEXT: fsub double %x, %rem
|
||||
; CHECK-NEXT: ret double %add
|
||||
|
||||
%rem = frem double -1.234000e-01, %y
|
||||
%add = fadd double %x, %rem
|
||||
ret double %add
|
||||
}
|
69
test/Transforms/Reassociate/liftsign.ll
Normal file
69
test/Transforms/Reassociate/liftsign.ll
Normal file
@ -0,0 +1,69 @@
|
||||
; RUN: opt -reassociate -gvn -S < %s | FileCheck %s
|
||||
|
||||
; (x + 0.1234 * y) * (x + -0.1234 * y) -> (x + 0.1234 * y) * (x - 0.1234 * y)
|
||||
; so CSE can simplify it further
|
||||
define double @lift_sign1(double %x, double %y) nounwind readnone ssp uwtable {
|
||||
; CHECK-LABEL: @lift_sign1(
|
||||
%mul = fmul double 1.234000e-01, %y
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double -1.234000e-01, %y
|
||||
%add2 = fadd double %mul1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
; CHECK-NOT: %mul1 = fmul double -1.234000e-01, %y
|
||||
; CHECK-NOT: %add2 = fadd %mul1, %x
|
||||
; CHECK: %add2.repl = fsub double %x, %mul
|
||||
; CHECK: %mul3 = fmul double %add, %add2
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + -0.1234 * y) * (x + -0.1234 * y) -> (x - 0.1234 * y) * (x - 0.1234 * y)
|
||||
; GVN can then rewrite it even further
|
||||
define double @lift_sign2(double %x, double %y) nounwind readnone ssp uwtable {
|
||||
; CHECK-LABEL: @lift_sign2(
|
||||
%mul = fmul double %y, -1.234000e-01
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double %y, -1.234000e-01
|
||||
%add2 = fadd double %mul1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
; CHECK-NOT: %mul = fmul double %y, -1.234000e-01
|
||||
; CHECK-NOT: %add = fadd double %mul, %x
|
||||
; CHECK-NOT: %mul1 = fmul double %y, -1.234000e-01
|
||||
; CHECK-NOT: %add2 = fadd double %mul1, %x
|
||||
; CHECK-NOT: %mul3 = fmul double %add, %add2
|
||||
; CHECK: %mul = fmul double 1.234000e-01, %y
|
||||
; CHECK: %add.repl = fsub double %x, %mul
|
||||
; CHECK: %mul3 = fmul double %add.repl, %add.repl
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + 0.1234 * y) * (x - -0.1234 * y) -> (x + 0.1234 * y) * (x + 0.1234 * y)
|
||||
define double @lift_sign3(double %x, double %y) nounwind readnone ssp uwtable {
|
||||
; CHECK-LABEL: @lift_sign3(
|
||||
%mul = fmul double %y, 1.234000e-01
|
||||
%add = fadd double %mul, %x
|
||||
%mul1 = fmul double %y, -1.234000e-01
|
||||
%add2 = fsub double %x, %mul1
|
||||
%mul3 = fmul double %add, %add2
|
||||
; CHECK-NOT: %mul1 = fmul double %y, -1.234000e-01
|
||||
; CHECK-NOT: %add2 = fsub double %x, %mul1
|
||||
; CHECK-NOT: %mul3 = fmul double %add, %add2
|
||||
; CHECK: %mul3 = fmul double %add, %add
|
||||
ret double %mul3
|
||||
}
|
||||
|
||||
; (x + 0.1234 / y) * (x + -0.1234 / y) -> (x + 0.1234 / y) * (x - 0.1234 / y)
|
||||
; so CSE can simplify it further
|
||||
define double @lift_sign4(double %x, double %y) nounwind readnone ssp uwtable {
|
||||
; CHECK-LABEL: @lift_sign4(
|
||||
%div = fdiv double 1.234000e-01, %y
|
||||
%add = fadd double %div, %x
|
||||
%div1 = fdiv double -1.234000e-01, %y
|
||||
%add2 = fadd double %div1, %x
|
||||
%mul3 = fmul double %add, %add2
|
||||
; CHECK-NOT: %div1 = fdiv double -1.234000e-01, %y
|
||||
; CHECK-NOT: %add2 = fadd double %div1, %x
|
||||
; CHECK-NOT: %mul3 = fmul double %add, %add2
|
||||
; CHECK: %add2.repl = fsub double %x, %div
|
||||
; CHECK: %mul3 = fmul double %add, %add2.repl
|
||||
ret double %mul3
|
||||
}
|
Loading…
Reference in New Issue
Block a user