[llvm] [RISCV] Generate bexti for (select(setcc eq (and x, c))) where c is power of 2. (PR #73649)

[Craig Topper via llvm-commits]

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@@ -3648,7 +3645,7 @@ define i64 @single_bit(i64 %x) {
 ;
 ; RV64XVENTANACONDOPS-LABEL: single_bit:
 ; RV64XVENTANACONDOPS:       # %bb.0: # %entry
-; RV64XVENTANACONDOPS-NEXT:    andi a1, a0, 1024
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topperc wrote:

Isn't ANDI better, especially if we can use c.andi?

https://github.com/llvm/llvm-project/pull/73649