AMDGPU/GlobalISel: Tolerate copies with no type set

[arsenm]

Summary

isVCC has the same bug, but isn't used in a context where it can cause
a problem.

[tstellar]

LGTM.

[arsenm]

r364784

lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp

 
 static bool isSCC(Register Reg, const MachineRegisterInfo &MRI) {
   if (TargetRegisterInfo::isPhysicalRegister(Reg))
     return Reg == AMDGPU::SCC;
 
   auto &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
   const TargetRegisterClass *RC =
       RegClassOrBank.dyn_cast<const TargetRegisterClass*>();
-  if (RC)
-    return RC->getID() == AMDGPU::SReg_32_XM0RegClassID &&
-           MRI.getType(Reg).getSizeInBits() == 1;
+  if (RC) {
+    if (RC->getID() != AMDGPU::SReg_32_XM0RegClassID)
+      return false;
+    const LLT Ty = MRI.getType(Reg);
+    return Ty.isValid() && Ty.getSizeInBits() == 1;
+  }
 
   const RegisterBank *RB = RegClassOrBank.get<const RegisterBank *>();
   return RB->getID() == AMDGPU::SCCRegBankID;
 }
 
 bool AMDGPUInstructionSelector::isVCC(Register Reg,
                                       const MachineRegisterInfo &MRI) const {
   if (TargetRegisterInfo::isPhysicalRegister(Reg))

test/CodeGen/AMDGPU/GlobalISel/inst-select-copy.mir

bb.0:
     %2:vgpr(s32) = COPY $vgpr3
     %3:scc(s1) = COPY $scc
     %4:vcc(s1) = COPY %3
     %5:vgpr(s32) = G_SELECT %4, %1, %2
     %6:vcc(s1) = COPY %3
     %7:vgpr(s32) = G_SELECT %6, %1, %5
     G_STORE %7, %0 :: (store 4, addrspace 1)
 ...
+
+---
+
+name:            copy_sgpr_no_type
+legalized:       true
+regBankSelected: true
+
+
+body: |
+  bb.0:
+    liveins: $sgpr0
+    ; GCN-LABEL: name: copy_sgpr_no_type
+    ; GCN: [[COPY:%[0-9]+]]:sreg_32_xm0 = COPY $sgpr0
+    ; GCN: S_ENDPGM 0, implicit [[COPY]]
+    %0:sreg_32_xm0 = COPY $sgpr0
+    %1:sreg_32_xm0 = COPY %0
+    S_ENDPGM 0, implicit %1
+
+...
+
+---
+
+name:            copy_vgpr_no_type
+legalized:       true
+regBankSelected: true
+
+
+body: |
+  bb.0:
+    liveins: $vgpr0
+    ; GCN-LABEL: name: copy_vgpr_no_type
+    ; GCN: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr0
+    ; GCN: S_ENDPGM 0, implicit [[COPY]]
+    %0:vgpr_32 = COPY $vgpr0
+    %1:vgpr_32 = COPY %0
+    S_ENDPGM 0, implicit %1
+
+...
+
 ---
+
+name:            copy_maybe_vcc
+legalized:       true
+regBankSelected: true
+
+
+body: |
+  bb.0:
+    liveins: $sgpr0_sgpr1
+    ; GCN-LABEL: name: copy_maybe_vcc
+    ; GCN: [[COPY:%[0-9]+]]:sreg_64_xexec = COPY $sgpr0_sgpr1
+    ; GCN: S_ENDPGM 0, implicit [[COPY]]
+    %0:sreg_64_xexec = COPY $sgpr0_sgpr1
+    %1:sreg_64_xexec  = COPY %0
+    S_ENDPGM 0, implicit %1
+
+...