[llvm] [IndVars] Support decrementing counters in LFTR (PR #225619)

[Craig Topper via llvm-commits]

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@@ -119,13 +119,16 @@ define void @zext_preinc(ptr %A, i32 %start) {
 ; CHECK-NEXT:    br i1 [[NONPOS]], label [[EXIT:%.*]], label [[FOR_BODY_PREHEADER:%.*]]
 ; CHECK:       for.body.preheader:
 ; CHECK-NEXT:    [[TMP0:%.*]] = zext i32 [[START]] to i64
+; CHECK-NEXT:    [[UMIN:%.*]] = call i32 @llvm.umin.i32(i32 [[START]], i32 6)
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topperc wrote:

How does this umin affect the final assembly?

https://github.com/llvm/llvm-project/pull/225619