[llvm] [SCEV] Rework IncrementWrapFlags (PR #219559)

[Ramkumar Ramachandra via llvm-commits]

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@@ -364,14 +364,17 @@ define void @doit4(i32 %n, i8 signext %cstep) {
 ; CHECK-NEXT:    [[MUL_OVERFLOW:%.*]] = extractvalue { i8, i1 } [[MUL]], 1
 ; CHECK-NEXT:    [[TMP5:%.*]] = sub i8 0, [[MUL_RESULT]]
 ; CHECK-NEXT:    [[TMP6:%.*]] = icmp slt i8 [[MUL_RESULT]], 0
-; CHECK-NEXT:    [[TMP7:%.*]] = icmp sgt i8 [[TMP5]], 0
+; CHECK-NEXT:    [[TMP7:%.*]] = icmp ugt i8 [[TMP5]], 0
 ; CHECK-NEXT:    [[TMP8:%.*]] = select i1 [[TMP2]], i1 [[TMP7]], i1 [[TMP6]]
 ; CHECK-NEXT:    [[TMP9:%.*]] = or i1 [[TMP8]], [[MUL_OVERFLOW]]
 ; CHECK-NEXT:    [[TMP10:%.*]] = icmp ugt i64 [[TMP0]], 255
 ; CHECK-NEXT:    [[TMP11:%.*]] = icmp ne i8 [[CSTEP]], 0
 ; CHECK-NEXT:    [[TMP12:%.*]] = and i1 [[TMP10]], [[TMP11]]
 ; CHECK-NEXT:    [[TMP13:%.*]] = or i1 [[TMP9]], [[TMP12]]
-; CHECK-NEXT:    br i1 [[TMP13]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]
+; CHECK-NEXT:    [[TMP14:%.*]] = zext i8 [[CSTEP]] to i32
+; CHECK-NEXT:    [[IDENT_CHECK:%.*]] = icmp ne i32 [[CONV]], [[TMP14]]
+; CHECK-NEXT:    [[TMP18:%.*]] = or i1 [[TMP13]], [[IDENT_CHECK]]
+; CHECK-NEXT:    br i1 [[TMP18]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]
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artagnon wrote:

I believe an underlying issue has been fixed here.

https://github.com/llvm/llvm-project/pull/219559