[llvm] [PowerPC] Add DMR and WACC COPY support (PR #149129)

[Lei Huang via llvm-commits]

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@@ -1863,6 +1864,48 @@ void PPCInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
         .addReg(SrcRegSub1)
         .addReg(SrcRegSub1, getKillRegState(KillSrc));
     return;
+  } else if ((PPC::WACCRCRegClass.contains(DestReg) ||
+              PPC::WACC_HIRCRegClass.contains(DestReg)) &&
+             (PPC::WACCRCRegClass.contains(SrcReg) ||
+              PPC::WACC_HIRCRegClass.contains(SrcReg))) {
+
+    Opc = PPC::WACCRCRegClass.contains(SrcReg) ? PPC::DMXXEXTFDMR512
+                                               : PPC::DMXXEXTFDMR512_HI;
+
+    RegScavenger RS;
+    RS.enterBasicBlockEnd(MBB);
+    RS.backward(std::next(I));
+
+    Register TmpReg1 = RS.scavengeRegisterBackwards(PPC::VSRpRCRegClass, I,
+                                                    /* RestoreAfter */ false, 0,
+                                                    /* AllowSpill */ false);
+
+    RS.setRegUsed(TmpReg1);
+    Register TmpReg2 = RS.scavengeRegisterBackwards(PPC::VSRpRCRegClass, I,
+                                                    /* RestoreAfter */ false, 0,
+                                                    /* AllowSpill */ false);
+
+    BuildMI(MBB, I, DL, get(Opc))
+        .addReg(TmpReg1, RegState::Define)
+        .addReg(TmpReg2, RegState::Define)
+        .addReg(SrcReg, getKillRegState(KillSrc));
+
+    Opc = PPC::WACCRCRegClass.contains(DestReg) ? PPC::DMXXINSTDMR512
+                                                : PPC::DMXXINSTDMR512_HI;
+
+    BuildMI(MBB, I, DL, get(Opc), DestReg)
+        .addReg(TmpReg1, RegState::Kill)
+        .addReg(TmpReg2, RegState::Kill);
+
+    return;
+  } else if (PPC::DMRRCRegClass.contains(DestReg) &&
+             PPC::DMRRCRegClass.contains(SrcReg)) {
+
+    BuildMI(MBB, I, DL, get(PPC::DMMR), DestReg)
----------------
lei137 wrote:

`PPC::DMR`?

https://github.com/llvm/llvm-project/pull/149129