[llvm] [SCEV] Make invalidation in SCEVCallbackVH more thorough (PR #68316)

[Florian Hahn via llvm-commits]

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@@ -114,46 +114,46 @@ define void @nestedIV(ptr %address, i32 %limit) nounwind {
 ; CHECK-LABEL: @nestedIV(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[LIMITDEC:%.*]] = add i32 [[LIMIT:%.*]], -1
+; CHECK-NEXT:    [[TMP0:%.*]] = sext i32 [[LIMITDEC]] to i64
 ; CHECK-NEXT:    [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[LIMIT]], i32 1)
-; CHECK-NEXT:    [[WIDE_TRIP_COUNT4:%.*]] = zext i32 [[SMAX]] to i64
+; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[SMAX]] to i64
 ; CHECK-NEXT:    br label [[OUTERLOOP:%.*]]
 ; CHECK:       outerloop:
 ; CHECK-NEXT:    [[INDVARS_IV1:%.*]] = phi i64 [ [[INDVARS_IV_NEXT2:%.*]], [[OUTERMERGE:%.*]] ], [ 0, [[ENTRY:%.*]] ]
 ; CHECK-NEXT:    [[INNERCOUNT:%.*]] = phi i32 [ [[INNERCOUNT_MERGE:%.*]], [[OUTERMERGE]] ], [ 0, [[ENTRY]] ]
-; CHECK-NEXT:    [[TMP0:%.*]] = add nsw i64 [[INDVARS_IV1]], -1
-; CHECK-NEXT:    [[ADR1:%.*]] = getelementptr i8, ptr [[ADDRESS:%.*]], i64 [[TMP0]]
+; CHECK-NEXT:    [[TMP1:%.*]] = add nsw i64 [[INDVARS_IV1]], -1
+; CHECK-NEXT:    [[ADR1:%.*]] = getelementptr i8, ptr [[ADDRESS:%.*]], i64 [[TMP1]]
 ; CHECK-NEXT:    store i8 0, ptr [[ADR1]], align 1
 ; CHECK-NEXT:    br label [[INNERPREHEADER:%.*]]
 ; CHECK:       innerpreheader:
 ; CHECK-NEXT:    [[INNERPRECMP:%.*]] = icmp sgt i32 [[LIMITDEC]], [[INNERCOUNT]]
 ; CHECK-NEXT:    br i1 [[INNERPRECMP]], label [[INNERLOOP_PREHEADER:%.*]], label [[OUTERMERGE]]
 ; CHECK:       innerloop.preheader:
-; CHECK-NEXT:    [[TMP1:%.*]] = sext i32 [[INNERCOUNT]] to i64
-; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = sext i32 [[LIMITDEC]] to i64
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fhahn wrote:

looks like this has the nice side effect of hoisting the sext out of the loop.

https://github.com/llvm/llvm-project/pull/68316