[llvm] [Exegesis][RISCV] Add initial RVV support (PR #128767)

[Min-Yih Hsu via llvm-commits]

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@@ -53,6 +53,8 @@ computeAliasingInstructions(const LLVMState &State, const Instruction *Instr,
     if (OtherOpcode == Instr->Description.getOpcode())
       continue;
     const Instruction &OtherInstr = State.getIC().getInstr(OtherOpcode);
+    if (ET.getIgnoredOpcodeReasonOrNull(State, OtherInstr.getOpcode()))
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mshockwave wrote:

For some reason this filter was removed when RISCV's exegesis was first introduced. But it really should be here.

https://github.com/llvm/llvm-project/pull/128767