GlobalISel: Move splitToValueTypes to generic code

I copied the nearly identical function from AArch64 into AMDGPU, so
fix this duplication.

Mips and X86 have their own more exotic versions which should be
removed. However replacing those is better left for a separate patch
since it requires other changes to avoid regressions.

llvm/include/llvm/CodeGen/GlobalISel/CallLowering.h

@@ -244,6 +244,13 @@ protected:
   void setArgFlags(ArgInfo &Arg, unsigned OpIdx, const DataLayout &DL,
                    const FuncInfoTy &FuncInfo) const;
 
+  /// Break \p OrigArgInfo into one or more pieces the calling convention can
+  /// process, returned in \p SplitArgs. For example, this should break structs
+  /// down into individual fields.
+  void splitToValueTypes(const ArgInfo &OrigArgInfo,
+                         SmallVectorImpl<ArgInfo> &SplitArgs,
+                         const DataLayout &DL, CallingConv::ID CallConv) const;
+
   /// Generate instructions for packing \p SrcRegs into one big register
   /// corresponding to the aggregate type \p PackedTy.
   ///

llvm/lib/CodeGen/GlobalISel/CallLowering.cpp

@@ -187,6 +187,43 @@ CallLowering::setArgFlags<CallBase>(CallLowering::ArgInfo &Arg, unsigned OpIdx,
                                     const DataLayout &DL,
                                     const CallBase &FuncInfo) const;
 
+void CallLowering::splitToValueTypes(const ArgInfo &OrigArg,
+                                     SmallVectorImpl<ArgInfo> &SplitArgs,
+                                     const DataLayout &DL,
+                                     CallingConv::ID CallConv) const {
+  LLVMContext &Ctx = OrigArg.Ty->getContext();
+
+  SmallVector<EVT, 4> SplitVTs;
+  SmallVector<uint64_t, 4> Offsets;
+  ComputeValueVTs(*TLI, DL, OrigArg.Ty, SplitVTs, &Offsets, 0);
+
+  if (SplitVTs.size() == 0)
+    return;
+
+  if (SplitVTs.size() == 1) {
+    // No splitting to do, but we want to replace the original type (e.g. [1 x
+    // double] -> double).
+    SplitArgs.emplace_back(OrigArg.Regs[0], SplitVTs[0].getTypeForEVT(Ctx),
+                           OrigArg.Flags[0], OrigArg.IsFixed);
+    return;
+  }
+
+  // Create one ArgInfo for each virtual register in the original ArgInfo.
+  assert(OrigArg.Regs.size() == SplitVTs.size() && "Regs / types mismatch");
+
+  bool NeedsRegBlock = TLI->functionArgumentNeedsConsecutiveRegisters(
+      OrigArg.Ty, CallConv, false);
+  for (unsigned i = 0, e = SplitVTs.size(); i < e; ++i) {
+    Type *SplitTy = SplitVTs[i].getTypeForEVT(Ctx);
+    SplitArgs.emplace_back(OrigArg.Regs[i], SplitTy, OrigArg.Flags[0],
+                           OrigArg.IsFixed);
+    if (NeedsRegBlock)
+      SplitArgs.back().Flags[0].setInConsecutiveRegs();
+  }
+
+  SplitArgs.back().Flags[0].setInConsecutiveRegsLast();
+}
+
 Register CallLowering::packRegs(ArrayRef<Register> SrcRegs, Type *PackedTy,
                                 MachineIRBuilder &MIRBuilder) const {
   assert(SrcRegs.size() > 1 && "Nothing to pack");

llvm/lib/Target/AArch64/GISel/AArch64CallLowering.cpp

@@ -285,43 +285,6 @@ static bool doesCalleeRestoreStack(CallingConv::ID CallConv, bool TailCallOpt) {
   return CallConv == CallingConv::Fast && TailCallOpt;
 }
 
-void AArch64CallLowering::splitToValueTypes(
-    const ArgInfo &OrigArg, SmallVectorImpl<ArgInfo> &SplitArgs,
-    const DataLayout &DL, MachineRegisterInfo &MRI, CallingConv::ID CallConv) const {
-  const AArch64TargetLowering &TLI = *getTLI<AArch64TargetLowering>();
-  LLVMContext &Ctx = OrigArg.Ty->getContext();
-
-  SmallVector<EVT, 4> SplitVTs;
-  SmallVector<uint64_t, 4> Offsets;
-  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs, &Offsets, 0);
-
-  if (SplitVTs.size() == 0)
-    return;
-
-  if (SplitVTs.size() == 1) {
-    // No splitting to do, but we want to replace the original type (e.g. [1 x
-    // double] -> double).
-    SplitArgs.emplace_back(OrigArg.Regs[0], SplitVTs[0].getTypeForEVT(Ctx),
-                           OrigArg.Flags[0], OrigArg.IsFixed);
-    return;
-  }
-
-  // Create one ArgInfo for each virtual register in the original ArgInfo.
-  assert(OrigArg.Regs.size() == SplitVTs.size() && "Regs / types mismatch");
-
-  bool NeedsRegBlock = TLI.functionArgumentNeedsConsecutiveRegisters(
-      OrigArg.Ty, CallConv, false);
-  for (unsigned i = 0, e = SplitVTs.size(); i < e; ++i) {
-    Type *SplitTy = SplitVTs[i].getTypeForEVT(Ctx);
-    SplitArgs.emplace_back(OrigArg.Regs[i], SplitTy, OrigArg.Flags[0],
-                           OrigArg.IsFixed);
-    if (NeedsRegBlock)
-      SplitArgs.back().Flags[0].setInConsecutiveRegs();
-  }
-
-  SplitArgs.back().Flags[0].setInConsecutiveRegsLast();
-}
-
 bool AArch64CallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
                                       const Value *Val,
                                       ArrayRef<Register> VRegs,
@@ -423,7 +386,7 @@ bool AArch64CallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
         // Reset the arg flags after modifying CurVReg.
         setArgFlags(CurArgInfo, AttributeList::ReturnIndex, DL, F);
       }
-     splitToValueTypes(CurArgInfo, SplitArgs, DL, MRI, CC);
+      splitToValueTypes(CurArgInfo, SplitArgs, DL, CC);
     }
 
     OutgoingArgHandler Handler(MIRBuilder, MRI, MIB, AssignFn, AssignFn);
@@ -508,7 +471,7 @@ bool AArch64CallLowering::lowerFormalArguments(
     ArgInfo OrigArg{VRegs[i], Arg.getType()};
     setArgFlags(OrigArg, i + AttributeList::FirstArgIndex, DL, F);
 
-    splitToValueTypes(OrigArg, SplitArgs, DL, MRI, F.getCallingConv());
+    splitToValueTypes(OrigArg, SplitArgs, DL, F.getCallingConv());
     ++i;
   }
 
@@ -986,7 +949,7 @@ bool AArch64CallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
 
   SmallVector<ArgInfo, 8> OutArgs;
   for (auto &OrigArg : Info.OrigArgs) {
-    splitToValueTypes(OrigArg, OutArgs, DL, MRI, Info.CallConv);
+    splitToValueTypes(OrigArg, OutArgs, DL, Info.CallConv);
     // AAPCS requires that we zero-extend i1 to 8 bits by the caller.
     if (OrigArg.Ty->isIntegerTy(1))
       OutArgs.back().Flags[0].setZExt();
@@ -994,7 +957,7 @@ bool AArch64CallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
 
   SmallVector<ArgInfo, 8> InArgs;
   if (!Info.OrigRet.Ty->isVoidTy())
-    splitToValueTypes(Info.OrigRet, InArgs, DL, MRI, Info.CallConv);
+    splitToValueTypes(Info.OrigRet, InArgs, DL, Info.CallConv);
 
   // If we can lower as a tail call, do that instead.
   bool CanTailCallOpt =

llvm/lib/Target/AArch64/GISel/AArch64CallLowering.h

@@ -64,11 +64,6 @@ private:
   using MemHandler =
       std::function<void(MachineIRBuilder &, int, CCValAssign &)>;
 
-  void splitToValueTypes(const ArgInfo &OrigArgInfo,
-                         SmallVectorImpl<ArgInfo> &SplitArgs,
-                         const DataLayout &DL, MachineRegisterInfo &MRI,
-                         CallingConv::ID CallConv) const;
-
   bool lowerTailCall(MachineIRBuilder &MIRBuilder, CallLoweringInfo &Info,
                      SmallVectorImpl<ArgInfo> &OutArgs) const;
 

llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp

@@ -278,47 +278,6 @@ static ISD::NodeType extOpcodeToISDExtOpcode(unsigned MIOpc) {
   }
 }
 
-// FIXME: This should move to generic code.
-void AMDGPUCallLowering::splitToValueTypes(MachineIRBuilder &B,
-                                           const ArgInfo &OrigArg,
-                                           SmallVectorImpl<ArgInfo> &SplitArgs,
-                                           const DataLayout &DL,
-                                           CallingConv::ID CallConv) const {
-  const SITargetLowering &TLI = *getTLI<SITargetLowering>();
-  LLVMContext &Ctx = OrigArg.Ty->getContext();
-
-  SmallVector<EVT, 4> SplitVTs;
-  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs);
-
-  assert(OrigArg.Regs.size() == SplitVTs.size());
-
-  if (SplitVTs.size() == 0)
-    return;
-
-  if (SplitVTs.size() == 1) {
-    // No splitting to do, but we want to replace the original type (e.g. [1 x
-    // double] -> double).
-    SplitArgs.emplace_back(OrigArg.Regs[0], SplitVTs[0].getTypeForEVT(Ctx),
-                           OrigArg.Flags[0], OrigArg.IsFixed);
-    return;
-  }
-
-  // Create one ArgInfo for each virtual register in the original ArgInfo.
-  assert(OrigArg.Regs.size() == SplitVTs.size() && "Regs / types mismatch");
-
-  bool NeedsRegBlock = TLI.functionArgumentNeedsConsecutiveRegisters(
-      OrigArg.Ty, CallConv, false);
-  for (unsigned i = 0, e = SplitVTs.size(); i < e; ++i) {
-    Type *SplitTy = SplitVTs[i].getTypeForEVT(Ctx);
-    SplitArgs.emplace_back(OrigArg.Regs[i], SplitTy, OrigArg.Flags[0],
-                           OrigArg.IsFixed);
-    if (NeedsRegBlock)
-      SplitArgs.back().Flags[0].setInConsecutiveRegs();
-  }
-
-  SplitArgs.back().Flags[0].setInConsecutiveRegsLast();
-}
-
 void AMDGPUCallLowering::processSplitArgs(
     MachineIRBuilder &B, const ArgInfo &OrigArg,
     const SmallVectorImpl<ArgInfo> &SplitArg,
@@ -498,7 +457,7 @@ bool AMDGPUCallLowering::lowerReturnVal(MachineIRBuilder &B,
       setArgFlags(RetInfo, AttributeList::ReturnIndex, DL, F);
     }
 
-    splitToValueTypes(B, RetInfo, PreSplitRetInfos, DL, CC);
+    splitToValueTypes(RetInfo, PreSplitRetInfos, DL, CC);
 
     // FIXME: This splitting should mostly be done by handleAssignments
     processSplitArgs(B, RetInfo,
@@ -824,7 +783,7 @@ bool AMDGPUCallLowering::lowerFormalArguments(
     const unsigned OrigArgIdx = Idx + AttributeList::FirstArgIndex;
     setArgFlags(OrigArg, OrigArgIdx, DL, F);
 
-    splitToValueTypes(B, OrigArg, SplitArgs, DL, CC);
+    splitToValueTypes(OrigArg, SplitArgs, DL, CC);
     ++Idx;
   }
 
@@ -1117,7 +1076,7 @@ bool AMDGPUCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
 
   SmallVector<ArgInfo, 8> SplitArg;
   for (auto &OrigArg : Info.OrigArgs) {
-    splitToValueTypes(MIRBuilder, OrigArg, SplitArg, DL, Info.CallConv);
+    splitToValueTypes(OrigArg, SplitArg, DL, Info.CallConv);
 
     processSplitArgs(
       MIRBuilder, OrigArg, SplitArg, OutArgs, DL, Info.CallConv, true,
@@ -1232,7 +1191,7 @@ bool AMDGPUCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
     insertSRetLoads(MIRBuilder, Info.OrigRet.Ty, Info.OrigRet.Regs,
                     Info.DemoteRegister, Info.DemoteStackIndex);
   } else if (!Info.OrigRet.Ty->isVoidTy()) {
-    splitToValueTypes(MIRBuilder, Info.OrigRet, InArgs, DL, Info.CallConv);
+    splitToValueTypes(Info.OrigRet, InArgs, DL, Info.CallConv);
   }
 
   // Make sure the raw argument copies are inserted before the marshalling to

llvm/lib/Target/AMDGPU/AMDGPUCallLowering.h

@@ -31,10 +31,6 @@ class AMDGPUCallLowering final : public CallLowering {
   /// A function of this type is used to perform value split action.
   using SplitArgTy = std::function<void(ArrayRef<Register>, Register, LLT, LLT, int)>;
 
-  void splitToValueTypes(MachineIRBuilder &B, const ArgInfo &OrigArgInfo,
-                         SmallVectorImpl<ArgInfo> &SplitArgs,
-                         const DataLayout &DL, CallingConv::ID CallConv) const;
-
   void processSplitArgs(MachineIRBuilder &B, const ArgInfo &OrigArgInfo,
                         const SmallVectorImpl<ArgInfo> &SplitArg,
                         SmallVectorImpl<ArgInfo> &SplitArgs,

llvm/lib/Target/ARM/ARMCallLowering.cpp

@@ -186,51 +186,6 @@ struct ARMOutgoingValueHandler : public CallLowering::OutgoingValueHandler {
 
 } // end anonymous namespace
 
-void ARMCallLowering::splitToValueTypes(const ArgInfo &OrigArg,
-                                        SmallVectorImpl<ArgInfo> &SplitArgs,
-                                        MachineFunction &MF) const {
-  const ARMTargetLowering &TLI = *getTLI<ARMTargetLowering>();
-  LLVMContext &Ctx = OrigArg.Ty->getContext();
-  const DataLayout &DL = MF.getDataLayout();
-  const Function &F = MF.getFunction();
-
-  SmallVector<EVT, 4> SplitVTs;
-  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs, nullptr, nullptr, 0);
-  assert(OrigArg.Regs.size() == SplitVTs.size() && "Regs / types mismatch");
-
-  if (SplitVTs.size() == 1) {
-    // Even if there is no splitting to do, we still want to replace the
-    // original type (e.g. pointer type -> integer).
-    auto Flags = OrigArg.Flags[0];
-    Flags.setOrigAlign(DL.getABITypeAlign(OrigArg.Ty));
-    SplitArgs.emplace_back(OrigArg.Regs[0], SplitVTs[0].getTypeForEVT(Ctx),
-                           Flags, OrigArg.IsFixed);
-    return;
-  }
-
-  // Create one ArgInfo for each virtual register.
-  for (unsigned i = 0, e = SplitVTs.size(); i != e; ++i) {
-    EVT SplitVT = SplitVTs[i];
-    Type *SplitTy = SplitVT.getTypeForEVT(Ctx);
-    auto Flags = OrigArg.Flags[0];
-
-    Flags.setOrigAlign(DL.getABITypeAlign(SplitTy));
-
-    bool NeedsConsecutiveRegisters =
-        TLI.functionArgumentNeedsConsecutiveRegisters(
-            SplitTy, F.getCallingConv(), F.isVarArg());
-    if (NeedsConsecutiveRegisters) {
-      Flags.setInConsecutiveRegs();
-      if (i == e - 1)
-        Flags.setInConsecutiveRegsLast();
-    }
-
-    // FIXME: We also want to split SplitTy further.
-    Register PartReg = OrigArg.Regs[i];
-    SplitArgs.emplace_back(PartReg, SplitTy, Flags, OrigArg.IsFixed);
-  }
-}
-
 /// Lower the return value for the already existing \p Ret. This assumes that
 /// \p MIRBuilder's insertion point is correct.
 bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
@@ -243,7 +198,7 @@ bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
   auto &MF = MIRBuilder.getMF();
   const auto &F = MF.getFunction();
 
-  auto DL = MF.getDataLayout();
+  const auto &DL = MF.getDataLayout();
   auto &TLI = *getTLI<ARMTargetLowering>();
   if (!isSupportedType(DL, TLI, Val->getType()))
     return false;
@@ -252,7 +207,7 @@ bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
   setArgFlags(OrigRetInfo, AttributeList::ReturnIndex, DL, F);
 
   SmallVector<ArgInfo, 4> SplitRetInfos;
-  splitToValueTypes(OrigRetInfo, SplitRetInfos, MF);
+  splitToValueTypes(OrigRetInfo, SplitRetInfos, DL, F.getCallingConv());
 
   CCAssignFn *AssignFn =
       TLI.CCAssignFnForReturn(F.getCallingConv(), F.isVarArg());
@@ -430,7 +385,7 @@ bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
 
   auto &MF = MIRBuilder.getMF();
   auto &MBB = MIRBuilder.getMBB();
-  auto DL = MF.getDataLayout();
+  const auto &DL = MF.getDataLayout();
 
   for (auto &Arg : F.args()) {
     if (!isSupportedType(DL, TLI, Arg.getType()))
@@ -451,7 +406,7 @@ bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
     ArgInfo OrigArgInfo(VRegs[Idx], Arg.getType());
 
     setArgFlags(OrigArgInfo, Idx + AttributeList::FirstArgIndex, DL, F);
-    splitToValueTypes(OrigArgInfo, SplitArgInfos, MF);
+    splitToValueTypes(OrigArgInfo, SplitArgInfos, DL, F.getCallingConv());
 
     Idx++;
   }
@@ -548,7 +503,7 @@ bool ARMCallLowering::lowerCall(MachineIRBuilder &MIRBuilder, CallLoweringInfo &
     if (Arg.Flags[0].isByVal())
       return false;
 
-    splitToValueTypes(Arg, ArgInfos, MF);
+    splitToValueTypes(Arg, ArgInfos, DL, Info.CallConv);
   }
 
   auto ArgAssignFn = TLI.CCAssignFnForCall(Info.CallConv, Info.IsVarArg);
@@ -565,7 +520,7 @@ bool ARMCallLowering::lowerCall(MachineIRBuilder &MIRBuilder, CallLoweringInfo &
       return false;
 
     ArgInfos.clear();
-    splitToValueTypes(Info.OrigRet, ArgInfos, MF);
+    splitToValueTypes(Info.OrigRet, ArgInfos, DL, Info.CallConv);
     auto RetAssignFn = TLI.CCAssignFnForReturn(Info.CallConv, Info.IsVarArg);
     CallReturnHandler RetHandler(MIRBuilder, MRI, MIB, RetAssignFn);
     if (!handleAssignments(MIRBuilder, ArgInfos, RetHandler, Info.CallConv,

llvm/lib/Target/ARM/ARMCallLowering.h

@@ -47,12 +47,6 @@ private:
   bool lowerReturnVal(MachineIRBuilder &MIRBuilder, const Value *Val,
                       ArrayRef<Register> VRegs,
                       MachineInstrBuilder &Ret) const;
-
-  /// Split an argument into one or more arguments that the CC lowering can cope
-  /// with.
-  void splitToValueTypes(const ArgInfo &OrigArg,
-                         SmallVectorImpl<ArgInfo> &SplitArgs,
-                         MachineFunction &MF) const;
 };
 
 } // end namespace llvm

llvm/lib/Target/Mips/MipsCallLowering.cpp

@@ -664,6 +664,7 @@ void MipsCallLowering::subTargetRegTypeForCallingConv(
   }
 }
 
+// FIXME: This should be removed and the generic version used
 void MipsCallLowering::splitToValueTypes(
     const DataLayout &DL, const ArgInfo &OrigArg, unsigned OriginalIndex,
     SmallVectorImpl<ArgInfo> &SplitArgs,

llvm/lib/Target/X86/X86CallLowering.cpp

@@ -50,6 +50,7 @@ using namespace llvm;
 X86CallLowering::X86CallLowering(const X86TargetLowering &TLI)
     : CallLowering(&TLI) {}
 
+// FIXME: This should be removed and the generic version used
 bool X86CallLowering::splitToValueTypes(const ArgInfo &OrigArg,
                                         SmallVectorImpl<ArgInfo> &SplitArgs,
                                         const DataLayout &DL,