Add code enough for emission of reg-reg and reg-imm moves. This allows us to compile "ret i16 0" properly!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70710 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 37 insertions, 0 deletions

diff --git a/lib/Target/MSP430/MSP430InstrInfo.cpp b/lib/Target/MSP430/MSP430InstrInfo.cpp
index d644e63ade..c84c96e656 100644
--- a/lib/Target/MSP430/MSP430InstrInfo.cpp
+++ b/lib/Target/MSP430/MSP430InstrInfo.cpp
@@ -26,3 +26,40 @@ using namespace llvm;
 MSP430InstrInfo::MSP430InstrInfo(MSP430TargetMachine &tm)
   : TargetInstrInfoImpl(MSP430Insts, array_lengthof(MSP430Insts)),
     RI(*this), TM(tm) {}
+
+bool MSP430InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
+                                   MachineBasicBlock::iterator I,
+                                   unsigned DestReg, unsigned SrcReg,
+                                   const TargetRegisterClass *DestRC,
+                                   const TargetRegisterClass *SrcRC) const {
+  if (DestRC != SrcRC) {
+    // Not yet supported!
+    return false;
+  }
+
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  if (I != MBB.end()) DL = I->getDebugLoc();
+
+  BuildMI(MBB, I, DL, get(MSP430::MOV16rr), DestReg).addReg(SrcReg);
+  return true;
+}
+
+bool
+MSP430InstrInfo::isMoveInstr(const MachineInstr& MI,
+                             unsigned &SrcReg, unsigned &DstReg,
+                             unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
+  SrcSubIdx = DstSubIdx = 0; // No sub-registers yet.
+
+  switch (MI.getOpcode()) {
+  default:
+    return false;
+  case MSP430::MOV16rr:
+    assert(MI.getNumOperands() >= 2 &&
+           MI.getOperand(0).isReg() &&
+           MI.getOperand(1).isReg() &&
+           "invalid register-register move instruction");
+    SrcReg = MI.getOperand(1).getReg();
+    DstReg = MI.getOperand(0).getReg();
+    return true;
+  }
+}