[llvm] [AMDGPU][MC] GFX9 - allow op_sel in v_interp_p2_f16 (PR #150712)

[Shilei Tian via llvm-commits]

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@@ -9239,6 +9178,32 @@ static bool isRegOrImmWithInputMods(const MCInstrDesc &Desc, unsigned OpNum) {
                                    MCOI::OperandConstraint::TIED_TO) == -1;
 }
 
+void AMDGPUAsmParser::cvtOpSelHelper(MCInst &Inst, unsigned OpSel) {
+  unsigned Opc = Inst.getOpcode();
+  const AMDGPU::OpName Ops[] = {AMDGPU::OpName::src0, AMDGPU::OpName::src1,
+                                AMDGPU::OpName::src2};
+  const AMDGPU::OpName ModOps[] = {AMDGPU::OpName::src0_modifiers,
+                                   AMDGPU::OpName::src1_modifiers,
+                                   AMDGPU::OpName::src2_modifiers};
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shiltian wrote:

nit: I'd just merge these two, and then use `i` and `i + 3` if needed.

Also, `constexpr` can be used.

https://github.com/llvm/llvm-project/pull/150712