[llvm] [RISCV][NFC] Prepare for Short Forward Branch of branches with immediates (PR #182456)

[Sam Elliott via llvm-commits]

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@@ -159,14 +174,23 @@ def PseudoCCORN  : SFBALU_rr;
 def PseudoCCXNOR : SFBALU_rr;
 }
 
+// imm -> bcc_opcode
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lenary wrote:

Probably, given the intention will be to add new SDNodeXForms for the reg-imm versions.

https://github.com/llvm/llvm-project/pull/182456