[clang] [llvm] [AVR] Fix Avr indvar detection and strength reduction (missed optimization) (PR #152028)

[Tom Vijlbrief via llvm-commits]

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@@ -112,8 +112,8 @@ while.end:                                        ; preds = %while.body, %entry
 
 define void @store16predec(ptr %x, i16 %y) {
 ; CHECK-LABEL: store16predec:
-; CHECK: st -{{[XYZ]}}, {{.*}}
-; CHECK: st -{{[XYZ]}}, {{.*}}
+; TODO: st -{{[XYZ]}}, {{.*}}
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tomtor wrote:

I have rewritten them to be more specific. Note that for pre16 we have
sbiw r24, 2; movw r30, r24, use Z

https://github.com/llvm/llvm-project/pull/152028