[llvm] [AArch64][SVE] Fold ADD+CNTB to INCB and DECB (PR #118280)

[David Sherwood via llvm-commits]

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@@ -271,9 +271,9 @@ define void @str_with_off_15(ptr %ptr) {
 define void @str_with_off_15mulvl(ptr %ptr) {
 ; CHECK-LABEL: str_with_off_15mulvl:
 ; CHECK:       // %bb.0:
+; CHECK-NEXT:    incb x0, all, mul #15
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david-arm wrote:

I think it might still be worth being conservative and restricting it to the 1/2/4 forms because for other forms addvl may be better for register allocation, since the input and output registers are not tied.

https://github.com/llvm/llvm-project/pull/118280