[llvm] [AMDGPU] Fix VGPR lowering for V_DUAL_FMAMK_F32 (PR #170567)

[Shilei Tian via llvm-commits]

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@@ -3450,6 +3450,12 @@ getVGPRLoweringOperandTables(const MCInstrDesc &Desc) {
   static const AMDGPU::OpName VOP2MADMKOps[4] = {
       AMDGPU::OpName::src0, AMDGPU::OpName::NUM_OPERAND_NAMES,
       AMDGPU::OpName::src1, AMDGPU::OpName::vdst};
+  static const AMDGPU::OpName VOPDFMAMKOpsX[4] = {
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shiltian wrote:

And this is gonna need something different in the downstream version as well. :-D

https://github.com/llvm/llvm-project/pull/170567