Support Linux on z as a Swift platform

lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp

@@ -1047,6 +1047,11 @@ void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
   case ELF::R_390_64:
     writeInt64BE(LocalAddress, Value + Addend);
     break;
+  case ELF::R_390_PC64: {
+    int64_t Delta = (Value + Addend) - Section.getLoadAddressWithOffset(Offset);
+    writeInt64BE(LocalAddress, Delta);
+    break;
+  }
   }
 }
 

lib/Target/SystemZ/SystemZAsmPrinter.cpp

@@ -260,6 +260,11 @@ void SystemZAsmPrinter::EmitInstruction(const MachineInstr *MI) {
         .addImm(15).addReg(SystemZ::R0D);
     break;
 
+  // Emit nothing here but a comment if we can.
+  case SystemZ::MemBarrier:
+    OutStreamer->emitRawComment("MEMBARRIER");
+    return;
+
   default:
     Lower.lower(MI, LoweredMI);
     break;

lib/Target/SystemZ/SystemZCallingConv.td

@@ -33,6 +33,9 @@ def RetCC_SystemZ : CallingConv<[
   // Promote i32 to i64 if it has an explicit extension type.
   CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>,
 
+  // A SwiftError is returned in R9.
+  CCIfSwiftError<CCIfType<[i64], CCAssignToReg<[R9D]>>>,
+
   // ABI-compliant code returns 64-bit integers in R2.  Make the other
   // call-clobbered argument registers available for code that doesn't
   // care about the ABI.  (R6 is an argument register too, but is
@@ -65,6 +68,12 @@ def CC_SystemZ : CallingConv<[
   // are smaller than 64 bits shouldn't.
   CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>,
 
+  // A SwiftSelf is passed in callee-saved R10.
+  CCIfSwiftSelf<CCIfType<[i64], CCAssignToReg<[R10D]>>>,
+
+  // A SwiftError is passed in callee-saved R9.
+  CCIfSwiftError<CCIfType<[i64], CCAssignToReg<[R9D]>>>,
+
   // Force long double values to the stack and pass i64 pointers to them.
   CCIfType<[f128], CCPassIndirect<i64>>,
 
@@ -105,3 +114,6 @@ def CC_SystemZ : CallingConv<[
 //===----------------------------------------------------------------------===//
 def CSR_SystemZ : CalleeSavedRegs<(add (sequence "R%dD", 6, 15),
                                        (sequence "F%dD", 8, 15))>;
+
+// R9 is used to return SwiftError; remove it from CSR.
+def CSR_SystemZ_SwiftError : CalleeSavedRegs<(sub CSR_SystemZ, R9D)>;

lib/Target/SystemZ/SystemZISelLowering.cpp

@@ -216,6 +216,8 @@ SystemZTargetLowering::SystemZTargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::ATOMIC_LOAD_UMAX, MVT::i32, Custom);
   setOperationAction(ISD::ATOMIC_CMP_SWAP,  MVT::i32, Custom);
 
+  setOperationAction(ISD::ATOMIC_FENCE, MVT::Other, Custom);
+
   // z10 has instructions for signed but not unsigned FP conversion.
   // Handle unsigned 32-bit types as signed 64-bit types.
   if (!Subtarget.hasFPExtension()) {
@@ -987,9 +989,11 @@ LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
 }
 
 static bool canUseSiblingCall(const CCState &ArgCCInfo,
-                              SmallVectorImpl<CCValAssign> &ArgLocs) {
+                              SmallVectorImpl<CCValAssign> &ArgLocs,
+                              SmallVectorImpl<ISD::OutputArg> &Outs) {
   // Punt if there are any indirect or stack arguments, or if the call
-  // needs the call-saved argument register R6.
+  // needs the callee-saved argument register R6, or if the call uses
+  // the callee-saved register arguments SwiftSelf and SwiftError.
   for (unsigned I = 0, E = ArgLocs.size(); I != E; ++I) {
     CCValAssign &VA = ArgLocs[I];
     if (VA.getLocInfo() == CCValAssign::Indirect)
@@ -999,6 +1003,8 @@ static bool canUseSiblingCall(const CCState &ArgCCInfo,
     unsigned Reg = VA.getLocReg();
     if (Reg == SystemZ::R6H || Reg == SystemZ::R6L || Reg == SystemZ::R6D)
       return false;
+    if (Outs[I].Flags.isSwiftSelf() || Outs[I].Flags.isSwiftError())
+      return false;
   }
   return true;
 }
@@ -1032,7 +1038,7 @@ SystemZTargetLowering::LowerCall(CallLoweringInfo &CLI,
 
   // We don't support GuaranteedTailCallOpt, only automatically-detected
   // sibling calls.
-  if (IsTailCall && !canUseSiblingCall(ArgCCInfo, ArgLocs))
+  if (IsTailCall && !canUseSiblingCall(ArgCCInfo, ArgLocs, Outs))
     IsTailCall = false;
 
   // Get a count of how many bytes are to be pushed on the stack.
@@ -1849,7 +1855,7 @@ static unsigned getTestUnderMaskCond(unsigned BitSize, unsigned CCMask,
     if (CCMask == SystemZ::CCMASK_CMP_NE)
       return SystemZ::CCMASK_TM_SOME_1;
   }
-  if (EffectivelyUnsigned && CmpVal <= Low) {
+  if (EffectivelyUnsigned && CmpVal > 0 && CmpVal <= Low) {
     if (CCMask == SystemZ::CCMASK_CMP_LT)
       return SystemZ::CCMASK_TM_ALL_0;
     if (CCMask == SystemZ::CCMASK_CMP_GE)
@@ -2640,6 +2646,57 @@ SDValue SystemZTargetLowering::lowerConstantPool(ConstantPoolSDNode *CP,
   return DAG.getNode(SystemZISD::PCREL_WRAPPER, DL, PtrVT, Result);
 }
 
+SDValue SystemZTargetLowering::lowerFRAMEADDR(SDValue Op,
+                                              SelectionDAG &DAG) const {
+  MachineFunction &MF = DAG.getMachineFunction();
+  MachineFrameInfo *MFI = MF.getFrameInfo();
+  MFI->setFrameAddressIsTaken(true);
+
+  SDLoc DL(Op);
+  unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+  EVT PtrVT = getPointerTy(DAG.getDataLayout());
+
+  // If the back chain frame index has not been allocated yet, do so.
+  SystemZMachineFunctionInfo *FI = MF.getInfo<SystemZMachineFunctionInfo>();
+  int BackChainIdx = FI->getFramePointerSaveIndex();
+  if (!BackChainIdx) {
+    // By definition, the frame address is the address of the back chain.
+    BackChainIdx = MFI->CreateFixedObject(8, -SystemZMC::CallFrameSize, false);
+    FI->setFramePointerSaveIndex(BackChainIdx);
+  }
+  SDValue BackChain = DAG.getFrameIndex(BackChainIdx, PtrVT);
+
+  // FIXME The frontend should detect this case.
+  if (Depth > 0) {
+    report_fatal_error("Unsupported stack frame traversal count");
+  }
+
+  return BackChain;
+}
+
+SDValue SystemZTargetLowering::lowerRETURNADDR(SDValue Op,
+                                               SelectionDAG &DAG) const {
+  MachineFunction &MF = DAG.getMachineFunction();
+  MachineFrameInfo *MFI = MF.getFrameInfo();
+  MFI->setReturnAddressIsTaken(true);
+
+  if (verifyReturnAddressArgumentIsConstant(Op, DAG))
+    return SDValue();
+
+  SDLoc DL(Op);
+  unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
+  EVT PtrVT = getPointerTy(DAG.getDataLayout());
+
+  // FIXME The frontend should detect this case.
+  if (Depth > 0) {
+    report_fatal_error("Unsupported stack frame traversal count");
+  }
+
+  // Return R14D, which has the return address. Mark it an implicit live-in.
+  unsigned LinkReg = MF.addLiveIn(SystemZ::R14D, &SystemZ::GR64BitRegClass);
+  return DAG.getCopyFromReg(DAG.getEntryNode(), DL, LinkReg, PtrVT);
+}
+
 SDValue SystemZTargetLowering::lowerBITCAST(SDValue Op,
                                             SelectionDAG &DAG) const {
   SDLoc DL(Op);
@@ -3031,6 +3088,25 @@ SDValue SystemZTargetLowering::lowerCTPOP(SDValue Op,
   return Op;
 }
 
+SDValue SystemZTargetLowering::lowerATOMIC_FENCE(SDValue Op,
+                                                 SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  AtomicOrdering FenceOrdering = static_cast<AtomicOrdering>(
+    cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue());
+  SynchronizationScope FenceScope = static_cast<SynchronizationScope>(
+    cast<ConstantSDNode>(Op.getOperand(2))->getZExtValue());
+
+  // The only fence that needs an instruction is a sequentially-consistent
+  // cross-thread fence.
+  if (FenceOrdering == SequentiallyConsistent && FenceScope == CrossThread) {
+    return SDValue(DAG.getMachineNode(SystemZ::Serialize, DL, MVT::Other,
+                                      Op.getOperand(0)), 0);
+  }
+
+  // MEMBARRIER is a compiler barrier; it codegens to a no-op.
+  return DAG.getNode(SystemZISD::MEMBARRIER, DL, MVT::Other, Op.getOperand(0));
+}
+
 // Op is an atomic load.  Lower it into a normal volatile load.
 SDValue SystemZTargetLowering::lowerATOMIC_LOAD(SDValue Op,
                                                 SelectionDAG &DAG) const {
@@ -4312,6 +4388,10 @@ SDValue SystemZTargetLowering::lowerShift(SDValue Op, SelectionDAG &DAG,
 SDValue SystemZTargetLowering::LowerOperation(SDValue Op,
                                               SelectionDAG &DAG) const {
   switch (Op.getOpcode()) {
+  case ISD::FRAMEADDR:
+    return lowerFRAMEADDR(Op, DAG);
+  case ISD::RETURNADDR:
+    return lowerRETURNADDR(Op, DAG);
   case ISD::BR_CC:
     return lowerBR_CC(Op, DAG);
   case ISD::SELECT_CC:
@@ -4354,6 +4434,8 @@ SDValue SystemZTargetLowering::LowerOperation(SDValue Op,
   case ISD::CTTZ_ZERO_UNDEF:
     return DAG.getNode(ISD::CTTZ, SDLoc(Op),
                        Op.getValueType(), Op.getOperand(0));
+  case ISD::ATOMIC_FENCE:
+    return lowerATOMIC_FENCE(Op, DAG);
   case ISD::ATOMIC_SWAP:
     return lowerATOMIC_LOAD_OP(Op, DAG, SystemZISD::ATOMIC_SWAPW);
   case ISD::ATOMIC_STORE:
@@ -4457,6 +4539,7 @@ const char *SystemZTargetLowering::getTargetNodeName(unsigned Opcode) const {
     OPCODE(SEARCH_STRING);
     OPCODE(IPM);
     OPCODE(SERIALIZE);
+    OPCODE(MEMBARRIER);
     OPCODE(TBEGIN);
     OPCODE(TBEGIN_NOFLOAT);
     OPCODE(TEND);
@@ -5218,6 +5301,7 @@ SystemZTargetLowering::emitAtomicLoadMinMax(MachineInstr *MI,
 MachineBasicBlock *
 SystemZTargetLowering::emitAtomicCmpSwapW(MachineInstr *MI,
                                           MachineBasicBlock *MBB) const {
+
   MachineFunction &MF = *MBB->getParent();
   const SystemZInstrInfo *TII =
       static_cast<const SystemZInstrInfo *>(Subtarget.getInstrInfo());

lib/Target/SystemZ/SystemZISelLowering.h

@@ -146,6 +146,9 @@ enum NodeType : unsigned {
   // Perform a serialization operation.  (BCR 15,0 or BCR 14,0.)
   SERIALIZE,
 
+  // Compiler barrier only; generate a no-op.
+  MEMBARRIER,
+
   // Transaction begin.  The first operand is the chain, the second
   // the TDB pointer, and the third the immediate control field.
   // Returns chain and glue.
@@ -449,6 +452,10 @@ class SystemZTargetLowering : public TargetLowering {
                                       SelectionDAG &DAG) const override;
   SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
 
+  bool supportSwiftError() const override {
+    return true;
+  }
+
 private:
   const SystemZSubtarget &Subtarget;
 
@@ -467,6 +474,8 @@ class SystemZTargetLowering : public TargetLowering {
                             SelectionDAG &DAG) const;
   SDValue lowerJumpTable(JumpTableSDNode *JT, SelectionDAG &DAG) const;
   SDValue lowerConstantPool(ConstantPoolSDNode *CP, SelectionDAG &DAG) const;
+  SDValue lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
+  SDValue lowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerVASTART(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerVACOPY(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
@@ -477,6 +486,7 @@ class SystemZTargetLowering : public TargetLowering {
   SDValue lowerBITCAST(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerOR(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerCTPOP(SDValue Op, SelectionDAG &DAG) const;
+  SDValue lowerATOMIC_FENCE(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const;
   SDValue lowerATOMIC_LOAD_OP(SDValue Op, SelectionDAG &DAG,

lib/Target/SystemZ/SystemZInstrInfo.td

@@ -1224,6 +1224,10 @@ def PFDRL : PrefetchRILPC<"pfdrl", 0xC62, z_prefetch>;
 let hasSideEffects = 1 in
 def Serialize : Alias<2, (outs), (ins), [(z_serialize)]>;
 
+// A pseudo instruction that serves as a compiler barrier.
+let hasSideEffects = 1 in
+def MemBarrier : Pseudo<(outs), (ins), [(z_membarrier)]>;
+
 let Predicates = [FeatureInterlockedAccess1], Defs = [CC] in {
   def LAA   : LoadAndOpRSY<"laa",   0xEBF8, atomic_load_add_32, GR32>;
   def LAAG  : LoadAndOpRSY<"laag",  0xEBE8, atomic_load_add_64, GR64>;

lib/Target/SystemZ/SystemZMachineFunctionInfo.h

@@ -22,14 +22,15 @@ class SystemZMachineFunctionInfo : public MachineFunctionInfo {
   unsigned VarArgsFirstFPR;
   unsigned VarArgsFrameIndex;
   unsigned RegSaveFrameIndex;
+  int FramePointerSaveIndex;
   bool ManipulatesSP;
   unsigned NumLocalDynamics;
 
 public:
   explicit SystemZMachineFunctionInfo(MachineFunction &MF)
     : LowSavedGPR(0), HighSavedGPR(0), VarArgsFirstGPR(0), VarArgsFirstFPR(0),
-      VarArgsFrameIndex(0), RegSaveFrameIndex(0), ManipulatesSP(false),
-      NumLocalDynamics(0) {}
+      VarArgsFrameIndex(0), RegSaveFrameIndex(0), FramePointerSaveIndex(0),
+      ManipulatesSP(false), NumLocalDynamics(0) {}
 
   // Get and set the first call-saved GPR that should be saved and restored
   // by this function.  This is 0 if no GPRs need to be saved or restored.
@@ -59,6 +60,10 @@ class SystemZMachineFunctionInfo : public MachineFunctionInfo {
   unsigned getRegSaveFrameIndex() const { return RegSaveFrameIndex; }
   void setRegSaveFrameIndex(unsigned FI) { RegSaveFrameIndex = FI; }
 
+  // Get and set the frame index of where the old frame pointer is stored.
+  int getFramePointerSaveIndex() const { return FramePointerSaveIndex; }
+  void setFramePointerSaveIndex(int Idx) { FramePointerSaveIndex = Idx; }
+
   // Get and set whether the function directly manipulates the stack pointer,
   // e.g. through STACKSAVE or STACKRESTORE.
   bool getManipulatesSP() const { return ManipulatesSP; }

lib/Target/SystemZ/SystemZOperators.td

@@ -188,6 +188,8 @@ def z_udivrem64         : SDNode<"SystemZISD::UDIVREM64", SDT_ZGR128Binary64>;
 
 def z_serialize         : SDNode<"SystemZISD::SERIALIZE", SDTNone,
                                  [SDNPHasChain, SDNPMayStore]>;
+def z_membarrier        : SDNode<"SystemZISD::MEMBARRIER", SDTNone,
+                                 [SDNPHasChain, SDNPSideEffect]>;
 
 // Defined because the index is an i32 rather than a pointer.
 def z_vector_insert     : SDNode<"ISD::INSERT_VECTOR_ELT",

lib/Target/SystemZ/SystemZRegisterInfo.cpp

@@ -24,12 +24,20 @@ SystemZRegisterInfo::SystemZRegisterInfo()
 
 const MCPhysReg *
 SystemZRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
+  if (MF->getSubtarget().getTargetLowering()->supportSwiftError() &&
+      MF->getFunction()->getAttributes().hasAttrSomewhere(
+          Attribute::SwiftError))
+    return CSR_SystemZ_SwiftError_SaveList;
   return CSR_SystemZ_SaveList;
 }
 
 const uint32_t *
 SystemZRegisterInfo::getCallPreservedMask(const MachineFunction &MF,
                                           CallingConv::ID CC) const {
+  if (MF.getSubtarget().getTargetLowering()->supportSwiftError() &&
+      MF.getFunction()->getAttributes().hasAttrSomewhere(
+          Attribute::SwiftError))
+    return CSR_SystemZ_SwiftError_RegMask;
   return CSR_SystemZ_RegMask;
 }
 

test/CodeGen/SystemZ/atomic-fence-01.ll

@@ -0,0 +1,16 @@
+; Test (fast) serialization.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s --check-prefix=Z10
+; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z196  | FileCheck %s --check-prefix=Z196
+; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=zEC12 | FileCheck %s --check-prefix=ZEC12
+; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z13   | FileCheck %s --check-prefix=Z13
+
+define void @test() {
+; Z10:   bcr 15, %r0
+; Z196:  bcr 14, %r0
+; ZEC12: bcr 14, %r0
+; Z13:   bcr 14, %r0
+  fence seq_cst
+  ret void
+}
+

test/CodeGen/SystemZ/atomic-fence-02.ll

@@ -0,0 +1,13 @@
+; Serialization is emitted only for fence seq_cst.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+define void @test() {
+; CHECK: #MEMBARRIER
+  fence acquire
+; CHECK: #MEMBARRIER
+  fence release
+; CHECK: #MEMBARRIER
+  fence acq_rel
+  ret void
+}

test/CodeGen/SystemZ/frameaddr-01.ll

@@ -0,0 +1,28 @@
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; The current function's frame address is the address of
+; the optional back chain slot.
+define i8* @fp0() nounwind {
+entry:
+; CHECK-LABEL: fp0:
+; CHECK: la   %r2, 0(%r15)
+; CHECK: br   %r14
+  %0 = tail call i8* @llvm.frameaddress(i32 0)
+  ret i8* %0
+}
+
+; Check that the frame address is correct in a presence
+; of a stack frame.
+define i8* @fp0f() nounwind {
+entry:
+; CHECK-LABEL: fp0f:
+; CHECK: aghi %r15, -168
+; CHECK: la   %r2, 168(%r15)
+; CHECK: aghi %r15, 168
+; CHECK: br   %r14
+  %0 = alloca i64, align 8
+  %1 = tail call i8* @llvm.frameaddress(i32 0)
+  ret i8* %1
+}
+
+declare i8* @llvm.frameaddress(i32) nounwind readnone