[llvm] [RISCV] Select and/or/xor with certain constants to Zbb ANDN/ORN/XNOR (PR #120221)

[Piotr Fusik via llvm-commits]

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@@ -273,37 +240,21 @@ define i32 @compl(i32 %x) {
 }
 
 define i32 @orlow12(i32 %x) {
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pfusik wrote:

With Zbs this is:

        ori     a0, a0, 2047
        bseti   a0, a0, 11

and is not affected by this change. Shall I add `+zbs` or test both with and without?

https://github.com/llvm/llvm-project/pull/120221