1 files changed, 50 insertions, 46 deletions

diff --git a/llvm/lib/Target/SystemZ/SystemZRegisterInfo.cpp b/llvm/lib/Target/SystemZ/SystemZRegisterInfo.cpp
index 39ace5594b7f..0d5e7af92523 100644
--- a/llvm/lib/Target/SystemZ/SystemZRegisterInfo.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZRegisterInfo.cpp
@@ -87,6 +87,52 @@ SystemZRegisterInfo::getRegAllocationHints(unsigned VirtReg,
   bool BaseImplRetVal = TargetRegisterInfo::getRegAllocationHints(
       VirtReg, Order, Hints, MF, VRM, Matrix);
 
+  if (VRM != nullptr) {
+    // Add any two address hints after any copy hints.
+    SmallSet<unsigned, 4> TwoAddrHints;
+    for (auto &Use : MRI->reg_nodbg_instructions(VirtReg))
+      if (SystemZ::getTwoOperandOpcode(Use.getOpcode()) != -1) {
+        const MachineOperand *VRRegMO = nullptr;
+        const MachineOperand *OtherMO = nullptr;
+        const MachineOperand *CommuMO = nullptr;
+        if (VirtReg == Use.getOperand(0).getReg()) {
+          VRRegMO = &Use.getOperand(0);
+          OtherMO = &Use.getOperand(1);
+          if (Use.isCommutable())
+            CommuMO = &Use.getOperand(2);
+        } else if (VirtReg == Use.getOperand(1).getReg()) {
+          VRRegMO = &Use.getOperand(1);
+          OtherMO = &Use.getOperand(0);
+        } else if (VirtReg == Use.getOperand(2).getReg() &&
+                   Use.isCommutable()) {
+          VRRegMO = &Use.getOperand(2);
+          OtherMO = &Use.getOperand(0);
+        } else
+          continue;
+
+        auto tryAddHint = [&](const MachineOperand *MO) -> void {
+          Register Reg = MO->getReg();
+          Register PhysReg =
+            Register::isPhysicalRegister(Reg) ? Reg : VRM->getPhys(Reg);
+          if (PhysReg) {
+            if (MO->getSubReg())
+              PhysReg = getSubReg(PhysReg, MO->getSubReg());
+            if (VRRegMO->getSubReg())
+              PhysReg = getMatchingSuperReg(PhysReg, VRRegMO->getSubReg(),
+                                            MRI->getRegClass(VirtReg));
+            if (!MRI->isReserved(PhysReg) && !is_contained(Hints, PhysReg))
+              TwoAddrHints.insert(PhysReg);
+          }
+        };
+        tryAddHint(OtherMO);
+        if (CommuMO)
+          tryAddHint(CommuMO);
+      }
+    for (MCPhysReg OrderReg : Order)
+      if (TwoAddrHints.count(OrderReg))
+        Hints.push_back(OrderReg);
+  }
+
   if (MRI->getRegClass(VirtReg) == &SystemZ::GRX32BitRegClass) {
     SmallVector<unsigned, 8> Worklist;
     SmallSet<unsigned, 4> DoneRegs;
@@ -143,58 +189,14 @@ SystemZRegisterInfo::getRegAllocationHints(unsigned VirtReg,
     }
   }
 
-  if (VRM == nullptr)
-    return BaseImplRetVal;
-
-  // Add any two address hints after any copy hints.
-  SmallSet<unsigned, 4> TwoAddrHints;
-  for (auto &Use : MRI->reg_nodbg_instructions(VirtReg))
-    if (SystemZ::getTwoOperandOpcode(Use.getOpcode()) != -1) {
-      const MachineOperand *VRRegMO = nullptr;
-      const MachineOperand *OtherMO = nullptr;
-      const MachineOperand *CommuMO = nullptr;
-      if (VirtReg == Use.getOperand(0).getReg()) {
-        VRRegMO = &Use.getOperand(0);
-        OtherMO = &Use.getOperand(1);
-        if (Use.isCommutable())
-          CommuMO = &Use.getOperand(2);
-      } else if (VirtReg == Use.getOperand(1).getReg()) {
-        VRRegMO = &Use.getOperand(1);
-        OtherMO = &Use.getOperand(0);
-      } else if (VirtReg == Use.getOperand(2).getReg() && Use.isCommutable()) {
-        VRRegMO = &Use.getOperand(2);
-        OtherMO = &Use.getOperand(0);
-      } else
-        continue;
-
-      auto tryAddHint = [&](const MachineOperand *MO) -> void {
-        Register Reg = MO->getReg();
-        Register PhysReg =
-            Register::isPhysicalRegister(Reg) ? Reg : VRM->getPhys(Reg);
-        if (PhysReg) {
-          if (MO->getSubReg())
-            PhysReg = getSubReg(PhysReg, MO->getSubReg());
-          if (VRRegMO->getSubReg())
-            PhysReg = getMatchingSuperReg(PhysReg, VRRegMO->getSubReg(),
-                                          MRI->getRegClass(VirtReg));
-          if (!MRI->isReserved(PhysReg) && !is_contained(Hints, PhysReg))
-            TwoAddrHints.insert(PhysReg);
-        }
-      };
-      tryAddHint(OtherMO);
-      if (CommuMO)
-        tryAddHint(CommuMO);
-    }
-  for (MCPhysReg OrderReg : Order)
-    if (TwoAddrHints.count(OrderReg))
-      Hints.push_back(OrderReg);
-
   return BaseImplRetVal;
 }
 
 const MCPhysReg *
 SystemZRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
   const SystemZSubtarget &Subtarget = MF->getSubtarget<SystemZSubtarget>();
+  if (MF->getFunction().getCallingConv() == CallingConv::GHC)
+    return CSR_SystemZ_NoRegs_SaveList;
   if (MF->getFunction().getCallingConv() == CallingConv::AnyReg)
     return Subtarget.hasVector()? CSR_SystemZ_AllRegs_Vector_SaveList
                                 : CSR_SystemZ_AllRegs_SaveList;
@@ -209,6 +211,8 @@ const uint32_t *
 SystemZRegisterInfo::getCallPreservedMask(const MachineFunction &MF,
                                           CallingConv::ID CC) const {
   const SystemZSubtarget &Subtarget = MF.getSubtarget<SystemZSubtarget>();
+  if (CC == CallingConv::GHC)
+    return CSR_SystemZ_NoRegs_RegMask;
   if (CC == CallingConv::AnyReg)
     return Subtarget.hasVector()? CSR_SystemZ_AllRegs_Vector_RegMask
                                 : CSR_SystemZ_AllRegs_RegMask;