[GlobalISel][X86] Support vector type G_UNMERGE_VALUES selection.

Summary:
Support vector type G_UNMERGE_VALUES selection.
For now G_UNMERGE_VALUES marked as legal for any type, so nothing to do in legalizer.

Reviewers: t.p.northover, qcolombet, zvi, guyblank

Reviewed By: guyblank

Subscribers: rovka, kristof.beyls, guyblank, llvm-commits

Differential Revision: https://reviews.llvm.org/D33665

llvm-svn: 306971

1 files changed, 31 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86InstructionSelector.cpp b/llvm/lib/Target/X86/X86InstructionSelector.cpp
index a740000d517..9f5e80fcb5d 100644
--- a/llvm/lib/Target/X86/X86InstructionSelector.cpp
+++ b/llvm/lib/Target/X86/X86InstructionSelector.cpp
@@ -75,6 +75,8 @@ private:
   bool selectUadde(MachineInstr &I, MachineRegisterInfo &MRI,
                    MachineFunction &MF) const;
   bool selectCopy(MachineInstr &I, MachineRegisterInfo &MRI) const;
+  bool selectUnmergeValues(MachineInstr &I, MachineRegisterInfo &MRI,
+                           MachineFunction &MF) const;
   bool selectMergeValues(MachineInstr &I, MachineRegisterInfo &MRI,
                          MachineFunction &MF) const;
   bool selectInsert(MachineInstr &I, MachineRegisterInfo &MRI,
@@ -272,6 +274,8 @@ bool X86InstructionSelector::select(MachineInstr &I) const {
     return true;
   if (selectUadde(I, MRI, MF))
     return true;
+  if (selectUnmergeValues(I, MRI, MF))
+    return true;
   if (selectMergeValues(I, MRI, MF))
     return true;
   if (selectExtract(I, MRI, MF))
@@ -918,6 +922,33 @@ bool X86InstructionSelector::selectInsert(MachineInstr &I,
   return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
 }
 
+bool X86InstructionSelector::selectUnmergeValues(MachineInstr &I,
+                                                 MachineRegisterInfo &MRI,
+                                                 MachineFunction &MF) const {
+  if (I.getOpcode() != TargetOpcode::G_UNMERGE_VALUES)
+    return false;
+
+  // Split to extracts.
+  unsigned NumDefs = I.getNumOperands() - 1;
+  unsigned SrcReg = I.getOperand(NumDefs).getReg();
+  unsigned DefSize = MRI.getType(I.getOperand(0).getReg()).getSizeInBits();
+
+  for (unsigned Idx = 0; Idx < NumDefs; ++Idx) {
+
+    MachineInstr &ExtrInst =
+        *BuildMI(*I.getParent(), I, I.getDebugLoc(),
+                 TII.get(TargetOpcode::G_EXTRACT), I.getOperand(Idx).getReg())
+             .addReg(SrcReg)
+             .addImm(Idx * DefSize);
+
+    if (!select(ExtrInst))
+      return false;
+  }
+
+  I.eraseFromParent();
+  return true;
+}
+
 bool X86InstructionSelector::selectMergeValues(MachineInstr &I,
                                                MachineRegisterInfo &MRI,
                                                MachineFunction &MF) const {