GlobalISel: Implement moreElementsVector for implicit_def

llvm-svn: 353754

1 files changed, 29 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 249ad2998fb..0141d96ffc8 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -99,6 +99,9 @@ LegalizerHelper::legalizeInstrStep(MachineInstr &MI) {
   case FewerElements:
     LLVM_DEBUG(dbgs() << ".. Reduce number of elements\n");
     return fewerElementsVector(MI, Step.TypeIdx, Step.NewType);
+  case MoreElements:
+    LLVM_DEBUG(dbgs() << ".. Increase number of elements\n");
+    return moreElementsVector(MI, Step.TypeIdx, Step.NewType);
   case Custom:
     LLVM_DEBUG(dbgs() << ".. Custom legalization\n");
     return LI.legalizeCustom(MI, MRI, MIRBuilder, Observer) ? Legalized
@@ -877,6 +880,15 @@ void LegalizerHelper::narrowScalarDst(MachineInstr &MI, LLT NarrowTy,
   MO.setReg(DstTrunc);
 }
 
+void LegalizerHelper::moreElementsVectorDst(MachineInstr &MI, LLT WideTy,
+                                            unsigned OpIdx) {
+  MachineOperand &MO = MI.getOperand(OpIdx);
+  unsigned DstExt = MRI.createGenericVirtualRegister(WideTy);
+  MIRBuilder.setInsertPt(MIRBuilder.getMBB(), ++MIRBuilder.getInsertPt());
+  MIRBuilder.buildExtract(MO.getReg(), DstExt, 0);
+  MO.setReg(DstExt);
+}
+
 LegalizerHelper::LegalizeResult
 LegalizerHelper::widenScalarMergeValues(MachineInstr &MI, unsigned TypeIdx,
                                         LLT WideTy) {
@@ -2404,6 +2416,23 @@ LegalizerHelper::narrowScalarShift(MachineInstr &MI, unsigned TypeIdx,
 }
 
 LegalizerHelper::LegalizeResult
+LegalizerHelper::moreElementsVector(MachineInstr &MI, unsigned TypeIdx,
+                                    LLT MoreTy) {
+  MIRBuilder.setInstr(MI);
+  unsigned Opc = MI.getOpcode();
+  switch (Opc) {
+  case TargetOpcode::G_IMPLICIT_DEF: {
+    Observer.changingInstr(MI);
+    moreElementsVectorDst(MI, MoreTy, 0);
+    Observer.changedInstr(MI);
+    return Legalized;
+  }
+  default:
+    return UnableToLegalize;
+  }
+}
+
+LegalizerHelper::LegalizeResult
 LegalizerHelper::narrowScalarMul(MachineInstr &MI, unsigned TypeIdx, LLT NewTy) {
   unsigned DstReg = MI.getOperand(0).getReg();
   unsigned Src0 = MI.getOperand(1).getReg();