revert rL345717 : [InstSimplify] fold icmp based on range of abs/nabs
This can miscompile as shown in PR39510: https://bugs.llvm.org/show_bug.cgi?id=39510 llvm-svn: 345780
This commit is contained in:
Sanjay Patel
parent
b262d1631e
commit
72fe03f93b
|
|
@ -2996,45 +2996,6 @@ static Value *simplifyICmpWithBinOp(CmpInst::Predicate Pred, Value *LHS,
|
|||
return nullptr;
|
||||
}
|
||||
|
||||
static Value *simplifyICmpWithAbsNabs(CmpInst::Predicate Pred, Value *Op0,
|
||||
Value *Op1) {
|
||||
// We need a comparison with a constant.
|
||||
const APInt *C;
|
||||
if (!match(Op1, m_APInt(C)))
|
||||
return nullptr;
|
||||
|
||||
// matchSelectPattern returns the negation part of an abs pattern in SP1.
|
||||
// If the negate has an NSW flag, abs(INT_MIN) is undefined. Without that
|
||||
// constraint, we can't make a contiguous range for the result of abs.
|
||||
ICmpInst::Predicate AbsPred = ICmpInst::BAD_ICMP_PREDICATE;
|
||||
Value *SP0, *SP1;
|
||||
SelectPatternFlavor SPF = matchSelectPattern(Op0, SP0, SP1).Flavor;
|
||||
if (SPF == SelectPatternFlavor::SPF_ABS &&
|
||||
cast<Instruction>(SP1)->hasNoSignedWrap())
|
||||
// The result of abs(X) is >= 0 (with nsw).
|
||||
AbsPred = ICmpInst::ICMP_SGE;
|
||||
if (SPF == SelectPatternFlavor::SPF_NABS)
|
||||
// The result of -abs(X) is <= 0.
|
||||
AbsPred = ICmpInst::ICMP_SLE;
|
||||
|
||||
if (AbsPred == ICmpInst::BAD_ICMP_PREDICATE)
|
||||
return nullptr;
|
||||
|
||||
// Intersect the range of abs/nabs with the range of this icmp.
|
||||
// If there is no intersection, the icmp must be false.
|
||||
// If the intersection equals the range of abs/nabs, the icmp must be true.
|
||||
APInt Zero = APInt::getNullValue(C->getBitWidth());
|
||||
ConstantRange AbsRange = ConstantRange::makeExactICmpRegion(AbsPred, Zero);
|
||||
ConstantRange CmpRange = ConstantRange::makeExactICmpRegion(Pred, *C);
|
||||
ConstantRange Intersection = AbsRange.intersectWith(CmpRange);
|
||||
if (Intersection.isEmptySet())
|
||||
return getFalse(GetCompareTy(Op0));
|
||||
if (Intersection == AbsRange)
|
||||
return getTrue(GetCompareTy(Op0));
|
||||
|
||||
return nullptr;
|
||||
}
|
||||
|
||||
/// Simplify integer comparisons where at least one operand of the compare
|
||||
/// matches an integer min/max idiom.
|
||||
static Value *simplifyICmpWithMinMax(CmpInst::Predicate Pred, Value *LHS,
|
||||
|
|
@ -3466,9 +3427,6 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
|
|||
if (Value *V = simplifyICmpWithMinMax(Pred, LHS, RHS, Q, MaxRecurse))
|
||||
return V;
|
||||
|
||||
if (Value *V = simplifyICmpWithAbsNabs(Pred, LHS, RHS))
|
||||
return V;
|
||||
|
||||
// Simplify comparisons of related pointers using a powerful, recursive
|
||||
// GEP-walk when we have target data available..
|
||||
if (LHS->getType()->isPointerTy())
|
||||
|
|
|
|||
|
|
@ -5,7 +5,11 @@
|
|||
|
||||
define i1 @abs_nsw_is_positive(i32 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_positive(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i32 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[NEGX]], i32 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sgt i32 [[ABS]], -1
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 0
|
||||
%negx = sub nsw i32 0, %x
|
||||
|
|
@ -31,7 +35,11 @@ define i1 @abs_nsw_is_positive_sge(i32 %x) {
|
|||
|
||||
define i1 @abs_nsw_is_positive_reduced_range(i32 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_positive_reduced_range(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i32 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[NEGX]], i32 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sgt i32 [[ABS]], -42
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 0
|
||||
%negx = sub nsw i32 0, %x
|
||||
|
|
@ -91,7 +99,11 @@ define i1 @abs_nsw_is_not_negative(i32 %x) {
|
|||
|
||||
define i1 @abs_nsw_is_not_negative_sle(i32 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_not_negative_sle(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i32 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[NEGX]], i32 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sle i32 [[ABS]], -1
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 1
|
||||
%negx = sub nsw i32 0, %x
|
||||
|
|
@ -104,7 +116,11 @@ define i1 @abs_nsw_is_not_negative_sle(i32 %x) {
|
|||
|
||||
define i1 @abs_nsw_is_not_negative_reduced_range(i32 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_not_negative_reduced_range(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i32 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[NEGX]], i32 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp slt i32 [[ABS]], -24
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 0
|
||||
%negx = sub nsw i32 0, %x
|
||||
|
|
@ -151,7 +167,11 @@ define i1 @abs_nsw_is_not_negative_wrong_range(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_negative_or_0(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_negative_or_0(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp slt i32 [[NABS]], 1
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 0
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -164,7 +184,11 @@ define i1 @nabs_is_negative_or_0(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_negative_or_0_sle(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_negative_or_0_sle(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sle i32 [[NABS]], 0
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 1
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -177,7 +201,11 @@ define i1 @nabs_is_negative_or_0_sle(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_negative_or_0_reduced_range(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_negative_or_0_reduced_range(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp slt i32 [[NABS]], 421
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 1
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -207,7 +235,11 @@ define i1 @nabs_is_negative_or_0_wrong_range(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_not_over_0(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_not_over_0(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sgt i32 [[NABS]], 0
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 0
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -220,7 +252,11 @@ define i1 @nabs_is_not_over_0(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_not_over_0_sle(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_not_over_0_sle(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sge i32 [[NABS]], 1
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 1
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -233,7 +269,11 @@ define i1 @nabs_is_not_over_0_sle(i32 %x) {
|
|||
|
||||
define i1 @nabs_is_not_over_0_reduced_range(i32 %x) {
|
||||
; CHECK-LABEL: @nabs_is_not_over_0_reduced_range(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[X:%.*]], 1
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i32 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i32 [[X]], i32 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sgt i32 [[NABS]], 4223
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i32 %x, 1
|
||||
%negx = sub i32 0, %x
|
||||
|
|
@ -278,7 +318,11 @@ define i1 @abs_nsw_is_positive_eq(i32 %x) {
|
|||
|
||||
define i1 @abs_nsw_is_positive_ult(i8 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_positive_ult(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i8 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i8 [[NEGX]], i8 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp ult i8 [[ABS]], -117
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i8 %x, 0
|
||||
%negx = sub nsw i8 0, %x
|
||||
|
|
@ -291,7 +335,11 @@ define i1 @abs_nsw_is_positive_ult(i8 %x) {
|
|||
|
||||
define i1 @abs_nsw_is_not_negative_ugt(i8 %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_not_negative_ugt(
|
||||
; CHECK-NEXT: ret i1 false
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw i8 0, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i8 [[NEGX]], i8 [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp ugt i8 [[ABS]], 127
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i8 %x, 0
|
||||
%negx = sub nsw i8 0, %x
|
||||
|
|
@ -304,7 +352,11 @@ define i1 @abs_nsw_is_not_negative_ugt(i8 %x) {
|
|||
|
||||
define <2 x i1> @abs_nsw_is_not_negative_vec_splat(<2 x i32> %x) {
|
||||
; CHECK-LABEL: @abs_nsw_is_not_negative_vec_splat(
|
||||
; CHECK-NEXT: ret <2 x i1> zeroinitializer
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt <2 x i32> [[X:%.*]], zeroinitializer
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub nsw <2 x i32> zeroinitializer, [[X]]
|
||||
; CHECK-NEXT: [[ABS:%.*]] = select <2 x i1> [[CMP]], <2 x i32> [[NEGX]], <2 x i32> [[X]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp slt <2 x i32> [[ABS]], <i32 -8, i32 -8>
|
||||
; CHECK-NEXT: ret <2 x i1> [[R]]
|
||||
;
|
||||
%cmp = icmp slt <2 x i32> %x, zeroinitializer
|
||||
%negx = sub nsw <2 x i32> zeroinitializer, %x
|
||||
|
|
@ -317,7 +369,11 @@ define <2 x i1> @abs_nsw_is_not_negative_vec_splat(<2 x i32> %x) {
|
|||
|
||||
define i1 @nabs_is_negative_or_0_ne(i8 %x) {
|
||||
; CHECK-LABEL: @nabs_is_negative_or_0_ne(
|
||||
; CHECK-NEXT: ret i1 true
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub i8 0, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select i1 [[CMP]], i8 [[X]], i8 [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[NABS]], 12
|
||||
; CHECK-NEXT: ret i1 [[R]]
|
||||
;
|
||||
%cmp = icmp slt i8 %x, 0
|
||||
%negx = sub i8 0, %x
|
||||
|
|
@ -330,7 +386,11 @@ define i1 @nabs_is_negative_or_0_ne(i8 %x) {
|
|||
|
||||
define <3 x i1> @nabs_is_not_over_0_sle_vec_splat(<3 x i33> %x) {
|
||||
; CHECK-LABEL: @nabs_is_not_over_0_sle_vec_splat(
|
||||
; CHECK-NEXT: ret <3 x i1> zeroinitializer
|
||||
; CHECK-NEXT: [[CMP:%.*]] = icmp slt <3 x i33> [[X:%.*]], <i33 1, i33 1, i33 1>
|
||||
; CHECK-NEXT: [[NEGX:%.*]] = sub <3 x i33> zeroinitializer, [[X]]
|
||||
; CHECK-NEXT: [[NABS:%.*]] = select <3 x i1> [[CMP]], <3 x i33> [[X]], <3 x i33> [[NEGX]]
|
||||
; CHECK-NEXT: [[R:%.*]] = icmp sge <3 x i33> [[NABS]], <i33 1, i33 1, i33 1>
|
||||
; CHECK-NEXT: ret <3 x i1> [[R]]
|
||||
;
|
||||
%cmp = icmp slt <3 x i33> %x, <i33 1, i33 1, i33 1>
|
||||
%negx = sub <3 x i33> zeroinitializer, %x
|
||||
|
|
|
|||
Loading…
Reference in New Issue