[llvm] [RISCV][MC] Add aliases for beq/bne with x0 as the first argument => beqz/bnez (PR #139086)

[Craig Topper via llvm-commits]

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@@ -965,8 +965,12 @@ def : InstAlias<"sgtu $rd, $rs, $rt", (SLTU GPR:$rd, GPR:$rt, GPR:$rs), 0>;
 
 def : InstAlias<"beqz $rs, $offset",
                 (BEQ GPR:$rs,      X0, bare_simm13_lsb0:$offset)>;
+def : InstAlias<"beqz $rs, $offset",
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topperc wrote:

What guarantees the canonical order will be first in the matching table?

https://github.com/llvm/llvm-project/pull/139086