[llvm] [VPlan] Introduce vputils::getStrideExpr (NFC) (PR #216760)

[Ramkumar Ramachandra via llvm-commits]

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@@ -139,10 +139,10 @@ define void @single_constant_stride_int_iv(ptr %p) {
 ; CHECK-UF2-NEXT:    br label %[[VECTOR_BODY:.*]]
 ; CHECK-UF2:       [[VECTOR_BODY]]:
 ; CHECK-UF2-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
-; CHECK-UF2-NEXT:    [[TMP16:%.*]] = shl i64 [[INDEX]], 8
-; CHECK-UF2-NEXT:    [[TMP17:%.*]] = getelementptr i8, ptr [[P]], i64 [[TMP16]]
+; CHECK-UF2-NEXT:    [[TMP6:%.*]] = shl nuw i64 [[INDEX]], 8
+; CHECK-UF2-NEXT:    [[TMP17:%.*]] = getelementptr nuw i8, ptr [[P]], i64 [[TMP6]]
 ; CHECK-UF2-NEXT:    [[TMP18:%.*]] = mul i64 [[TMP3]], 256
-; CHECK-UF2-NEXT:    [[TMP14:%.*]] = getelementptr i8, ptr [[TMP17]], i64 [[TMP18]]
+; CHECK-UF2-NEXT:    [[TMP14:%.*]] = getelementptr nuw i8, ptr [[TMP17]], i64 [[TMP18]]
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artagnon wrote:

Oops, there was indeed a thinko -- looks like I was getting NWFlags from the wrong AddRec, thanks.

https://github.com/llvm/llvm-project/pull/216760