// Flags are intersected from the 2 source binops. But there are 2 exceptions:
// 1. If we changed an opcode, poison conditions might have changed.
// 2. If the shuffle had undef mask elements, the new binop might have undefs
- // where the original code did not. Drop all poison potential to be safe.
+ // where the original code did not. But if we already made a safe constant,
+ // then there's no danger.
NewBO->copyIRFlags(B0);
NewBO->andIRFlags(B1);
if (DropNSW)
NewBO->setHasNoSignedWrap(false);
- if (Mask->containsUndefElement())
+ if (Mask->containsUndefElement() && !MightCreatePoisonOrUB)
NewBO->dropPoisonGeneratingFlags();
return NewBO;
}
}
; Shift by undef is poison. Undef must be replaced by safe constant.
-; TODO: We could have propagated 'nuw' here.
define <4 x i32> @shl_shl_nuw_undef_mask_elt(<4 x i32> %v0) {
; CHECK-LABEL: @shl_shl_nuw_undef_mask_elt(
-; CHECK-NEXT: [[T3:%.*]] = shl <4 x i32> [[V0:%.*]], <i32 0, i32 6, i32 3, i32 0>
+; CHECK-NEXT: [[T3:%.*]] = shl nuw <4 x i32> [[V0:%.*]], <i32 0, i32 6, i32 3, i32 0>
; CHECK-NEXT: ret <4 x i32> [[T3]]
;
%t1 = shl nuw <4 x i32> %v0, <i32 1, i32 2, i32 3, i32 4>
ret <4 x i32> %t3
}
-; TODO: 'exact' could have propagated.
-
define <4 x i32> @sdiv_sdiv_exact_undef_mask_elt(<4 x i32> %v0) {
; CHECK-LABEL: @sdiv_sdiv_exact_undef_mask_elt(
-; CHECK-NEXT: [[T3:%.*]] = sdiv <4 x i32> [[V0:%.*]], <i32 1, i32 2, i32 7, i32 1>
+; CHECK-NEXT: [[T3:%.*]] = sdiv exact <4 x i32> [[V0:%.*]], <i32 1, i32 2, i32 7, i32 1>
; CHECK-NEXT: ret <4 x i32> [[T3]]
;
%t1 = sdiv exact <4 x i32> %v0, <i32 1, i32 2, i32 3, i32 4>
define <4 x i32> @shl_2_vars_nsw_undef_mask_elt(<4 x i32> %v0, <4 x i32> %v1) {
; CHECK-LABEL: @shl_2_vars_nsw_undef_mask_elt(
; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <4 x i32> [[V0:%.*]], <4 x i32> [[V1:%.*]], <4 x i32> <i32 undef, i32 5, i32 2, i32 undef>
-; CHECK-NEXT: [[T3:%.*]] = shl <4 x i32> [[TMP1]], <i32 0, i32 6, i32 3, i32 0>
+; CHECK-NEXT: [[T3:%.*]] = shl nsw <4 x i32> [[TMP1]], <i32 0, i32 6, i32 3, i32 0>
; CHECK-NEXT: ret <4 x i32> [[T3]]
;
%t1 = shl nsw <4 x i32> %v0, <i32 1, i32 2, i32 3, i32 4>
define <4 x i32> @sdiv_2_vars_exact_undef_mask_elt(<4 x i32> %v0, <4 x i32> %v1) {
; CHECK-LABEL: @sdiv_2_vars_exact_undef_mask_elt(
; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <4 x i32> [[V0:%.*]], <4 x i32> [[V1:%.*]], <4 x i32> <i32 0, i32 1, i32 6, i32 undef>
-; CHECK-NEXT: [[T3:%.*]] = sdiv <4 x i32> [[TMP1]], <i32 1, i32 2, i32 7, i32 1>
+; CHECK-NEXT: [[T3:%.*]] = sdiv exact <4 x i32> [[TMP1]], <i32 1, i32 2, i32 7, i32 1>
; CHECK-NEXT: ret <4 x i32> [[T3]]
;
%t1 = sdiv exact <4 x i32> %v0, <i32 1, i32 2, i32 3, i32 4>