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el-ev merged 4 commits into from
Apr 30, 2025
Merged

[ConstraintElim] Fix poison check before adding intrinsic facts #136291

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f4bf37b
[ConstraintElim] Fix poison check before adding intrinsic facts
el-ev Apr 18, 2025
3e63609
Merge branch 'main' into users/el-ev/04-18-_constraintelim_fix_poison…
el-ev Apr 30, 2025
4a30bfe
update
el-ev Apr 30, 2025
20b12a7
Merge branch 'main' into users/el-ev/04-18-_constraintelim_fix_poison…
el-ev Apr 30, 2025
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4 changes: 2 additions & 2 deletions llvm/lib/Transforms/Scalar/ConstraintElimination.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1137,10 +1137,10 @@ void State::addInfoFor(BasicBlock &BB) {
FactOrCheck::getCheck(DT.getNode(&BB), cast<CallInst>(&I)));
// TODO: Check if it is possible to instead only added the min/max facts
// when simplifying uses of the min/max intrinsics.
if (!isGuaranteedNotToBePoison(&I))
break;
[[fallthrough]];
case Intrinsic::abs:
if (!isGuaranteedNotToBePoison(&I))
break;
WorkList.push_back(FactOrCheck::getInstFact(DT.getNode(&BB), &I));
break;
}
Expand Down
146 changes: 111 additions & 35 deletions llvm/test/Transforms/ConstraintElimination/abs.ll
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Original file line number Diff line number Diff line change
@@ -1,9 +1,9 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
; RUN: opt -passes=constraint-elimination -S %s | FileCheck %s

define i1 @abs_int_min_is_not_poison(i32 %arg) {
define i1 @abs_int_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_int_min_is_not_poison(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: ret i1 true
;
Expand All @@ -12,87 +12,149 @@ define i1 @abs_int_min_is_not_poison(i32 %arg) {
ret i1 %cmp
}

define i1 @abs_int_min_is_poison(i32 %arg) {
define i1 @abs_int_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_int_min_is_poison(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: ret i1 true
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS]], [[ARG]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%cmp = icmp sge i32 %abs, %arg
ret i1 %cmp
}

define i1 @abs_plus_one(i32 %arg) {
; CHECK-LABEL: define i1 @abs_plus_one(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
define i1 @abs_plus_one_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_min_is_not_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[ABS_PLUS_ONE:%.*]] = add nsw i32 [[ABS]], 1
; CHECK-NEXT: ret i1 true
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%abs_plus_one = add nsw i32 %abs, 1
%cmp = icmp sge i32 %abs_plus_one, %arg
ret i1 %cmp
}

define i1 @arg_minus_one_strict_less(i32 %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_less(
; CHECK-SAME: i32 [[ARG:%.*]]) {
define i1 @abs_plus_one_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_min_is_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: [[ABS_PLUS_ONE:%.*]] = add nsw i32 [[ABS]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS_PLUS_ONE]], [[ARG]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs_plus_one = add nsw i32 %abs, 1
%cmp = icmp sge i32 %abs_plus_one, %arg
ret i1 %cmp
}

define i1 @arg_minus_one_strict_less_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_less_min_is_not_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[ARG_MINUS_ONE:%.*]] = add nsw i32 [[ARG]], -1
; CHECK-NEXT: ret i1 true
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%arg_minus_one = add nsw i32 %arg, -1
%cmp = icmp slt i32 %arg_minus_one, %abs
ret i1 %cmp
}

define i1 @arg_minus_one_strict_greater(i32 %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_greater(
; CHECK-SAME: i32 [[ARG:%.*]]) {

define i1 @arg_minus_one_strict_less_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_less_min_is_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: [[ARG_MINUS_ONE:%.*]] = add nsw i32 [[ARG]], -1
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[ARG_MINUS_ONE]], [[ABS]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%arg_minus_one = add nsw i32 %arg, -1
%cmp = icmp slt i32 %arg_minus_one, %abs
ret i1 %cmp
}

define i1 @arg_minus_one_strict_greater_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_greater_min_is_not_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[ARG_MINUS_ONE:%.*]] = add nsw i32 [[ARG]], -1
; CHECK-NEXT: ret i1 false
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%arg_minus_one = add nsw i32 %arg, -1
%cmp = icmp sgt i32 %arg_minus_one, %abs
ret i1 %cmp
}

define i1 @arg_minus_one_strict_greater_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @arg_minus_one_strict_greater_min_is_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: [[ARG_MINUS_ONE:%.*]] = add nsw i32 [[ARG]], -1
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[ARG_MINUS_ONE]], [[ABS]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%arg_minus_one = add nsw i32 %arg, -1
%cmp = icmp sgt i32 %arg_minus_one, %abs
ret i1 %cmp
}

define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg(i32 %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg(
; CHECK-SAME: i32 [[ARG:%.*]]) {
define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg_min_is_not_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[CMP_ARG_NONNEGATIVE:%.*]] = icmp sge i32 [[ARG]], 0
; CHECK-NEXT: call void @llvm.assume(i1 [[CMP_ARG_NONNEGATIVE]])
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[ABS_PLUS_ONE:%.*]] = add nuw i32 [[ABS]], 1
; CHECK-NEXT: ret i1 true
;
%cmp_arg_nonnegative = icmp sge i32 %arg, 0
call void @llvm.assume(i1 %cmp_arg_nonnegative)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%abs_plus_one = add nuw i32 %abs, 1
%cmp = icmp uge i32 %abs_plus_one, %arg
ret i1 %cmp
}

define i1 @abs_plus_one_unsigned_greater_or_equal_cannot_be_simplified(i32 %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_unsigned_greater_or_equal_cannot_be_simplified(
; CHECK-SAME: i32 [[ARG:%.*]]) {
define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_unsigned_greater_or_equal_nonnegative_arg_min_is_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[CMP_ARG_NONNEGATIVE:%.*]] = icmp sge i32 [[ARG]], 0
; CHECK-NEXT: call void @llvm.assume(i1 [[CMP_ARG_NONNEGATIVE]])
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: [[ABS_PLUS_ONE:%.*]] = add nuw i32 [[ABS]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp uge i32 [[ABS_PLUS_ONE]], [[ARG]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%cmp_arg_nonnegative = icmp sge i32 %arg, 0
call void @llvm.assume(i1 %cmp_arg_nonnegative)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs_plus_one = add nuw i32 %abs, 1
%cmp = icmp uge i32 %abs_plus_one, %arg
ret i1 %cmp
}

define i1 @abs_plus_one_unsigned_greater_or_equal_cannot_be_simplified(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_plus_one_unsigned_greater_or_equal_cannot_be_simplified(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[ABS_PLUS_ONE:%.*]] = add nuw i32 [[ABS]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp uge i32 [[ABS_PLUS_ONE]], [[ARG]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%abs_plus_one = add nuw i32 %abs, 1
%cmp = icmp uge i32 %abs_plus_one, %arg
ret i1 %cmp
}

define i1 @abs_constant_negative_arg() {
; CHECK-LABEL: define i1 @abs_constant_negative_arg() {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 -3, i1 false)
Expand All @@ -114,9 +176,9 @@ define i1 @abs_constant_positive_arg() {
ret i1 %cmp
}

define i1 @abs_is_nonnegative_except_for_int_min_if_int_min_is_not_poison(i32 %arg) {
define i1 @abs_is_nonnegative_except_for_int_min_if_int_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_is_nonnegative_except_for_int_min_if_int_min_is_not_poison(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS]], 0
; CHECK-NEXT: ret i1 [[CMP]]
Expand All @@ -126,23 +188,36 @@ define i1 @abs_is_nonnegative_except_for_int_min_if_int_min_is_not_poison(i32 %a
ret i1 %cmp
}

define i1 @abs_is_not_strictly_positive(i32 %arg) {
define i1 @abs_is_not_strictly_positive(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_is_not_strictly_positive(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[ABS]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%cmp = icmp sgt i32 %abs, 0
ret i1 %cmp
}

define i1 @abs_is_nonnegative_int_min_is_poison(i32 %arg) {
define i1 @abs_is_nonnegative_int_min_is_not_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_is_nonnegative_int_min_is_not_poison(
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 false)
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 false)
%cmp = icmp sge i32 %abs, 0
ret i1 %cmp
}

define i1 @abs_is_nonnegative_int_min_is_poison(i32 noundef %arg) {
; CHECK-LABEL: define i1 @abs_is_nonnegative_int_min_is_poison(
; CHECK-SAME: i32 [[ARG:%.*]]) {
; CHECK-SAME: i32 noundef [[ARG:%.*]]) {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 [[ARG]], i1 true)
; CHECK-NEXT: ret i1 true
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 %arg, i1 true)
%cmp = icmp sge i32 %abs, 0
Expand All @@ -152,7 +227,8 @@ define i1 @abs_is_nonnegative_int_min_is_poison(i32 %arg) {
define i1 @abs_is_nonnegative_constant_arg() {
; CHECK-LABEL: define i1 @abs_is_nonnegative_constant_arg() {
; CHECK-NEXT: [[ABS:%.*]] = tail call i32 @llvm.abs.i32(i32 -3, i1 true)
; CHECK-NEXT: ret i1 true
; CHECK-NEXT: [[CMP:%.*]] = icmp sge i32 [[ABS]], 0
; CHECK-NEXT: ret i1 [[CMP]]
;
%abs = tail call i32 @llvm.abs.i32(i32 -3, i1 true)
%cmp = icmp sge i32 %abs, 0
Expand Down
65 changes: 65 additions & 0 deletions llvm/test/Transforms/ConstraintElimination/uadd-usub-sat.ll
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Original file line number Diff line number Diff line change
@@ -0,0 +1,65 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
; RUN: opt -passes=constraint-elimination -S %s | FileCheck %s

declare i64 @llvm.uadd.sat.i64(i64, i64)
declare i64 @llvm.usub.sat.i64(i64, i64)

define i1 @uadd_sat_uge(i64 noundef %a, i64 noundef %b) {
; CHECK-LABEL: define i1 @uadd_sat_uge(
; CHECK-SAME: i64 noundef [[A:%.*]], i64 noundef [[B:%.*]]) {
; CHECK-NEXT: [[ADD_SAT:%.*]] = call i64 @llvm.uadd.sat.i64(i64 [[A]], i64 [[B]])
; CHECK-NEXT: [[CMP1:%.*]] = icmp uge i64 [[ADD_SAT]], [[A]]
; CHECK-NEXT: [[CMP2:%.*]] = icmp uge i64 [[ADD_SAT]], [[B]]
; CHECK-NEXT: [[CMP:%.*]] = and i1 [[CMP1]], [[CMP2]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%add.sat = call i64 @llvm.uadd.sat.i64(i64 %a, i64 %b)
%cmp1 = icmp uge i64 %add.sat, %a
%cmp2 = icmp uge i64 %add.sat, %b
%cmp = and i1 %cmp1, %cmp2
ret i1 %cmp
}

define i1 @usub_sat_ule_lhs(i64 noundef %a, i64 noundef %b) {
; CHECK-LABEL: define i1 @usub_sat_ule_lhs(
; CHECK-SAME: i64 noundef [[A:%.*]], i64 noundef [[B:%.*]]) {
; CHECK-NEXT: [[SUB_SAT:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[A]], i64 [[B]])
; CHECK-NEXT: [[CMP:%.*]] = icmp ule i64 [[SUB_SAT]], [[A]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%sub.sat = call i64 @llvm.usub.sat.i64(i64 %a, i64 %b)
%cmp = icmp ule i64 %sub.sat, %a
ret i1 %cmp
}

; Negative test
define i1 @usub_sat_not_ule_rhs(i64 noundef %a, i64 noundef %b) {
; CHECK-LABEL: define i1 @usub_sat_not_ule_rhs(
; CHECK-SAME: i64 noundef [[A:%.*]], i64 noundef [[B:%.*]]) {
; CHECK-NEXT: [[SUB_SAT:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[A]], i64 [[B]])
; CHECK-NEXT: [[CMP:%.*]] = icmp ule i64 [[SUB_SAT]], [[B]]
; CHECK-NEXT: ret i1 [[CMP]]
;
%sub.sat = call i64 @llvm.usub.sat.i64(i64 %a, i64 %b)
%cmp = icmp ule i64 %sub.sat, %b
ret i1 %cmp
}

define i1 @pr135603(i64 %conv6, i64 %str.coerce, ptr %conv) {
; CHECK-LABEL: define i1 @pr135603(
; CHECK-SAME: i64 [[CONV6:%.*]], i64 [[STR_COERCE:%.*]], ptr [[CONV:%.*]]) {
; CHECK-NEXT: [[A:%.*]] = load i32, ptr [[CONV]], align 4
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[A]], -1
; CHECK-NEXT: [[CONV2:%.*]] = zext nneg i32 [[A]] to i64
; CHECK-NEXT: [[ADD:%.*]] = add i64 [[STR_COERCE]], [[CONV6]]
; CHECK-NEXT: [[SPEC_SELECT:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[CONV2]], i64 [[ADD]])
; CHECK-NEXT: ret i1 [[CMP]]
;
%a = load i32, ptr %conv, align 4
%cmp = icmp sgt i32 %a, -1
%conv2 = zext nneg i32 %a to i64
%add = add i64 %str.coerce, %conv6
%spec.select = call i64 @llvm.usub.sat.i64(i64 %conv2, i64 %add)
ret i1 %cmp
}