AMDGPU/GlobalISel: Select G_PTR_MASK

llvm-svn: 371412
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp b/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
index b55ecd6..aea9ad8 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
@@ -1271,6 +1271,69 @@
     DstReg, IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass, MRI);
 }
 
+bool AMDGPUInstructionSelector::selectG_PTR_MASK(MachineInstr &I) const {
+  uint64_t Align = I.getOperand(2).getImm();
+  const uint64_t Mask = ~((UINT64_C(1) << Align) - 1);
+
+  MachineBasicBlock *BB = I.getParent();
+  MachineFunction *MF = BB->getParent();
+  MachineRegisterInfo &MRI = MF->getRegInfo();
+
+  Register DstReg = I.getOperand(0).getReg();
+  Register SrcReg = I.getOperand(1).getReg();
+
+  const RegisterBank *DstRB = RBI.getRegBank(DstReg, MRI, TRI);
+  const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, MRI, TRI);
+  const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
+  unsigned NewOpc = IsVGPR ? AMDGPU::V_AND_B32_e64 : AMDGPU::S_AND_B32;
+  unsigned MovOpc = IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32;
+  const TargetRegisterClass &RegRC
+    = IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass;
+
+  LLT Ty = MRI.getType(DstReg);
+
+  const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(Ty, *DstRB,
+                                                                  MRI);
+  const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(Ty, *SrcRB,
+                                                                  MRI);
+  if (!RBI.constrainGenericRegister(DstReg, *DstRC, MRI) ||
+      !RBI.constrainGenericRegister(SrcReg, *SrcRC, MRI))
+    return false;
+
+  const DebugLoc &DL = I.getDebugLoc();
+  Register ImmReg = MRI.createVirtualRegister(&RegRC);
+  BuildMI(*BB, &I, DL, TII.get(MovOpc), ImmReg)
+    .addImm(Mask);
+
+  if (Ty.getSizeInBits() == 32) {
+    BuildMI(*BB, &I, DL, TII.get(NewOpc), DstReg)
+      .addReg(SrcReg)
+      .addReg(ImmReg);
+    I.eraseFromParent();
+    return true;
+  }
+
+  Register HiReg = MRI.createVirtualRegister(&RegRC);
+  Register LoReg = MRI.createVirtualRegister(&RegRC);
+  Register MaskLo = MRI.createVirtualRegister(&RegRC);
+
+  BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), LoReg)
+    .addReg(SrcReg, 0, AMDGPU::sub0);
+  BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), HiReg)
+    .addReg(SrcReg, 0, AMDGPU::sub1);
+
+  BuildMI(*BB, &I, DL, TII.get(NewOpc), MaskLo)
+    .addReg(LoReg)
+    .addReg(ImmReg);
+  BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
+    .addReg(MaskLo)
+    .addImm(AMDGPU::sub0)
+    .addReg(HiReg)
+    .addImm(AMDGPU::sub1);
+  I.eraseFromParent();
+  return true;
+}
+
 bool AMDGPUInstructionSelector::select(MachineInstr &I) {
   if (I.isPHI())
     return selectPHI(I);
@@ -1354,6 +1417,8 @@
     // is checking for G_CONSTANT
     I.setDesc(TII.get(AMDGPU::ATOMIC_FENCE));
     return true;
+  case TargetOpcode::G_PTR_MASK:
+    return selectG_PTR_MASK(I);
   default:
     return selectImpl(I, *CoverageInfo);
   }
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h b/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
index ed51f8b..7d2538d 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
@@ -96,6 +96,7 @@
   bool selectG_SELECT(MachineInstr &I) const;
   bool selectG_BRCOND(MachineInstr &I) const;
   bool selectG_FRAME_INDEX(MachineInstr &I) const;
+  bool selectG_PTR_MASK(MachineInstr &I) const;
 
   std::pair<Register, unsigned>
   selectVOP3ModsImpl(Register Src, const MachineRegisterInfo &MRI) const;
diff --git a/llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp b/llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
index 5e5c9d7..6a08f04 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
@@ -392,6 +392,10 @@
     .legalForCartesianProduct(AddrSpaces32, {S32})
     .scalarize(0);
 
+  getActionDefinitionsBuilder(G_PTR_MASK)
+    .scalarize(0)
+    .alwaysLegal();
+
   setAction({G_BLOCK_ADDR, CodePtr}, Legal);
 
   auto &CmpBuilder =