Implement builtin_{setjmp/longjmp} on PPC

This implements SJLJ lowering on PPC, making the Clang functions
__builtin_{setjmp/longjmp} functional on PPC platforms. The implementation
strategy is similar to that on X86, with the exception that a branch-and-link
variant is used to get the right jump address. Credit goes to Bill Schmidt for
suggesting the use of the unconditional bcl form (instead of the regular bl
instruction) to limit return-address-cache pollution.

Benchmarking the speed at -O3 of:

static jmp_buf env_sigill;

void foo() {
                __builtin_longjmp(env_sigill,1);
}

main() {
	...

        for (int i = 0; i < c; ++i) {
                if (__builtin_setjmp(env_sigill)) {
                        goto done;
                } else {
                        foo();
                }

done:;
        }

	...
}

vs. the same code using the libc setjmp/longjmp functions on a P7 shows that
this builtin implementation is ~4x faster with Altivec enabled and ~7.25x
faster with Altivec disabled. This comparison is somewhat unfair because the
libc version must also save/restore the VSX registers which we don't yet
support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177666 91177308-0d34-0410-b5e6-96231b3b80d8

10 files changed, 475 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/PPCCallingConv.td b/lib/Target/PowerPC/PPCCallingConv.td
index caeb1796f7..2a680661d3 100644
--- a/lib/Target/PowerPC/PPCCallingConv.td
+++ b/lib/Target/PowerPC/PPCCallingConv.td
@@ -136,3 +136,8 @@ def CSR_SVR464   : CalleeSavedRegs<(add X14, X15, X16, X17, X18, X19, X20, VRSAV
                                         F27, F28, F29, F30, F31, CR2, CR3, CR4,
                                         V20, V21, V22, V23, V24, V25, V26, V27,
                                         V28, V29, V30, V31)>;
+
+def CSR_NoRegs : CalleeSavedRegs<(add)>;
+
+def CSR_NoRegs_Altivec : CalleeSavedRegs<(add (sequence "V%u", 0, 31), VRSAVE)>;
+
diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index 17bea8a6a6..90a3a5c6a4 100644
--- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -164,6 +164,12 @@ namespace {
       return PPCLowering.SelectAddressRegImmShift(N, Disp, Base, *CurDAG);
     }
 
+    // Select an address into a single register.
+    bool SelectAddr(SDValue N, SDValue &Base) {
+      Base = N;
+      return true;
+    }
+
     /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
     /// inline asm expressions.  It is always correct to compute the value into
     /// a register.  The case of adding a (possibly relocatable) constant to a
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 72cb6f535a..5e11f01b49 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -70,6 +70,7 @@ static TargetLoweringObjectFile *CreateTLOF(const PPCTargetMachine &TM) {
 PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
   : TargetLowering(TM, CreateTLOF(TM)), PPCSubTarget(*TM.getSubtargetImpl()) {
   const PPCSubtarget *Subtarget = &TM.getSubtarget<PPCSubtarget>();
+  PPCRegInfo = TM.getRegisterInfo();
 
   setPow2DivIsCheap();
 
@@ -211,6 +212,14 @@ PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
   setOperationAction(ISD::EXCEPTIONADDR, MVT::i32, Expand);
   setOperationAction(ISD::EHSELECTION,   MVT::i32, Expand);
 
+  // NOTE: EH_SJLJ_SETJMP/_LONGJMP supported here is NOT intened to support
+  // SjLj exception handling but a light-weight setjmp/longjmp replacement to
+  // support continuation, user-level threading, and etc.. As a result, no
+  // other SjLj exception interfaces are implemented and please don't build
+  // your own exception handling based on them.
+  // LLVM/Clang supports zero-cost DWARF exception handling.
+  setOperationAction(ISD::EH_SJLJ_SETJMP, MVT::i32, Custom);
+  setOperationAction(ISD::EH_SJLJ_LONGJMP, MVT::Other, Custom);
 
   // We want to legalize GlobalAddress and ConstantPool nodes into the
   // appropriate instructions to materialize the address.
@@ -567,6 +576,8 @@ const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
   case PPCISD::BCTRL_Darwin:    return "PPCISD::BCTRL_Darwin";
   case PPCISD::BCTRL_SVR4:      return "PPCISD::BCTRL_SVR4";
   case PPCISD::RET_FLAG:        return "PPCISD::RET_FLAG";
+  case PPCISD::EH_SJLJ_SETJMP:  return "PPCISD::EH_SJLJ_SETJMP";
+  case PPCISD::EH_SJLJ_LONGJMP: return "PPCISD::EH_SJLJ_LONGJMP";
   case PPCISD::MFCR:            return "PPCISD::MFCR";
   case PPCISD::VCMP:            return "PPCISD::VCMP";
   case PPCISD::VCMPo:           return "PPCISD::VCMPo";
@@ -4561,6 +4572,21 @@ SDValue PPCTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
   return DAG.getNode(PPCISD::DYNALLOC, dl, VTs, Ops, 3);
 }
 
+SDValue PPCTargetLowering::lowerEH_SJLJ_SETJMP(SDValue Op,
+                                               SelectionDAG &DAG) const {
+  DebugLoc DL = Op.getDebugLoc();
+  return DAG.getNode(PPCISD::EH_SJLJ_SETJMP, DL,
+                     DAG.getVTList(MVT::i32, MVT::Other),
+                     Op.getOperand(0), Op.getOperand(1));
+}
+
+SDValue PPCTargetLowering::lowerEH_SJLJ_LONGJMP(SDValue Op,
+                                                SelectionDAG &DAG) const {
+  DebugLoc DL = Op.getDebugLoc();
+  return DAG.getNode(PPCISD::EH_SJLJ_LONGJMP, DL, MVT::Other,
+                     Op.getOperand(0), Op.getOperand(1));
+}
+
 /// LowerSELECT_CC - Lower floating point select_cc's into fsel instruction when
 /// possible.
 SDValue PPCTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
@@ -5557,6 +5583,9 @@ SDValue PPCTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   case ISD::DYNAMIC_STACKALLOC:
     return LowerDYNAMIC_STACKALLOC(Op, DAG, PPCSubTarget);
 
+  case ISD::EH_SJLJ_SETJMP:     return lowerEH_SJLJ_SETJMP(Op, DAG);
+  case ISD::EH_SJLJ_LONGJMP:    return lowerEH_SJLJ_LONGJMP(Op, DAG);
+
   case ISD::SELECT_CC:          return LowerSELECT_CC(Op, DAG);
   case ISD::FP_TO_UINT:
   case ISD::FP_TO_SINT:         return LowerFP_TO_INT(Op, DAG,
@@ -5869,9 +5898,238 @@ PPCTargetLowering::EmitPartwordAtomicBinary(MachineInstr *MI,
   return BB;
 }
 
+llvm::MachineBasicBlock*
+PPCTargetLowering::emitEHSjLjSetJmp(MachineInstr *MI,
+                                    MachineBasicBlock *MBB) const {
+  DebugLoc DL = MI->getDebugLoc();
+  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
+
+  MachineFunction *MF = MBB->getParent();
+  MachineRegisterInfo &MRI = MF->getRegInfo();
+
+  const BasicBlock *BB = MBB->getBasicBlock();
+  MachineFunction::iterator I = MBB;
+  ++I;
+
+  // Memory Reference
+  MachineInstr::mmo_iterator MMOBegin = MI->memoperands_begin();
+  MachineInstr::mmo_iterator MMOEnd = MI->memoperands_end();
+
+  unsigned DstReg = MI->getOperand(0).getReg();
+  const TargetRegisterClass *RC = MRI.getRegClass(DstReg);
+  assert(RC->hasType(MVT::i32) && "Invalid destination!");
+  unsigned mainDstReg = MRI.createVirtualRegister(RC);
+  unsigned restoreDstReg = MRI.createVirtualRegister(RC);
+
+  MVT PVT = getPointerTy();
+  assert((PVT == MVT::i64 || PVT == MVT::i32) &&
+         "Invalid Pointer Size!");
+  // For v = setjmp(buf), we generate
+  //
+  // thisMBB:
+  //  SjLjSetup mainMBB
+  //  bl mainMBB
+  //  v_restore = 1
+  //  b sinkMBB
+  //
+  // mainMBB:
+  //  buf[LabelOffset] = LR
+  //  v_main = 0
+  //
+  // sinkMBB:
+  //  v = phi(main, restore)
+  //
+
+  MachineBasicBlock *thisMBB = MBB;
+  MachineBasicBlock *mainMBB = MF->CreateMachineBasicBlock(BB);
+  MachineBasicBlock *sinkMBB = MF->CreateMachineBasicBlock(BB);
+  MF->insert(I, mainMBB);
+  MF->insert(I, sinkMBB);
+
+  MachineInstrBuilder MIB;
+
+  // Transfer the remainder of BB and its successor edges to sinkMBB.
+  sinkMBB->splice(sinkMBB->begin(), MBB,
+                  llvm::next(MachineBasicBlock::iterator(MI)), MBB->end());
+  sinkMBB->transferSuccessorsAndUpdatePHIs(MBB);
+
+  // Note that the structure of the jmp_buf used here is not compatible
+  // with that used by libc, and is not designed to be. Specifically, it
+  // stores only those 'reserved' registers that LLVM does not otherwise
+  // understand how to spill. Also, by convention, by the time this
+  // intrinsic is called, Clang has already stored the frame address in the
+  // first slot of the buffer and stack address in the third. Following the
+  // X86 target code, we'll store the jump address in the second slot. We also
+  // need to save the TOC pointer (R2) to handle jumps between shared
+  // libraries, and that will be stored in the fourth slot. The thread
+  // identifier (R13) is not affected.
+
+  // thisMBB:
+  const int64_t LabelOffset = 1 * PVT.getStoreSize();
+  const int64_t TOCOffset   = 3 * PVT.getStoreSize();
+
+  // Prepare IP either in reg.
+  const TargetRegisterClass *PtrRC = getRegClassFor(PVT);
+  unsigned LabelReg = MRI.createVirtualRegister(PtrRC);
+  unsigned BufReg = MI->getOperand(1).getReg();
+
+  if (PPCSubTarget.isPPC64() && PPCSubTarget.isSVR4ABI()) {
+    MIB = BuildMI(*thisMBB, MI, DL, TII->get(PPC::STD))
+            .addReg(PPC::X2)
+            .addImm(TOCOffset / 4)
+            .addReg(BufReg);
+
+    MIB.setMemRefs(MMOBegin, MMOEnd);
+  }
+
+  // Setup
+  MIB = BuildMI(*thisMBB, MI, DL, TII->get(PPC::BCL)).addMBB(mainMBB);
+  MIB.addRegMask(PPCRegInfo->getNoPreservedMask());
+
+  BuildMI(*thisMBB, MI, DL, TII->get(PPC::LI), restoreDstReg).addImm(1);
+
+  MIB = BuildMI(*thisMBB, MI, DL, TII->get(PPC::EH_SjLj_Setup))
+          .addMBB(mainMBB);
+  MIB = BuildMI(*thisMBB, MI, DL, TII->get(PPC::B)).addMBB(sinkMBB);
+
+  thisMBB->addSuccessor(mainMBB, /* weight */ 0);
+  thisMBB->addSuccessor(sinkMBB, /* weight */ 1);
+
+  // mainMBB:
+  //  mainDstReg = 0
+  MIB = BuildMI(mainMBB, DL,
+    TII->get(PPCSubTarget.isPPC64() ? PPC::MFLR8 : PPC::MFLR), LabelReg);
+
+  // Store IP
+  if (PPCSubTarget.isPPC64()) {
+    MIB = BuildMI(mainMBB, DL, TII->get(PPC::STD))
+            .addReg(LabelReg)
+            .addImm(LabelOffset / 4)
+            .addReg(BufReg);
+  } else {
+    MIB = BuildMI(mainMBB, DL, TII->get(PPC::STW))
+            .addReg(LabelReg)
+            .addImm(LabelOffset)
+            .addReg(BufReg);
+  }
+
+  MIB.setMemRefs(MMOBegin, MMOEnd);
+
+  BuildMI(mainMBB, DL, TII->get(PPC::LI), mainDstReg).addImm(0);
+  mainMBB->addSuccessor(sinkMBB);
+
+  // sinkMBB:
+  BuildMI(*sinkMBB, sinkMBB->begin(), DL,
+          TII->get(PPC::PHI), DstReg)
+    .addReg(mainDstReg).addMBB(mainMBB)
+    .addReg(restoreDstReg).addMBB(thisMBB);
+
+  MI->eraseFromParent();
+  return sinkMBB;
+}
+
+MachineBasicBlock *
+PPCTargetLowering::emitEHSjLjLongJmp(MachineInstr *MI,
+                                     MachineBasicBlock *MBB) const {
+  DebugLoc DL = MI->getDebugLoc();
+  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
+
+  MachineFunction *MF = MBB->getParent();
+  MachineRegisterInfo &MRI = MF->getRegInfo();
+
+  // Memory Reference
+  MachineInstr::mmo_iterator MMOBegin = MI->memoperands_begin();
+  MachineInstr::mmo_iterator MMOEnd = MI->memoperands_end();
+
+  MVT PVT = getPointerTy();
+  assert((PVT == MVT::i64 || PVT == MVT::i32) &&
+         "Invalid Pointer Size!");
+
+  const TargetRegisterClass *RC =
+    (PVT == MVT::i64) ? &PPC::G8RCRegClass : &PPC::GPRCRegClass;
+  unsigned Tmp = MRI.createVirtualRegister(RC);
+  // Since FP is only updated here but NOT referenced, it's treated as GPR.
+  unsigned FP  = (PVT == MVT::i64) ? PPC::X31 : PPC::R31;
+  unsigned SP  = (PVT == MVT::i64) ? PPC::X1 : PPC::R1;
+
+  MachineInstrBuilder MIB;
+
+  const int64_t LabelOffset = 1 * PVT.getStoreSize();
+  const int64_t SPOffset    = 2 * PVT.getStoreSize();
+  const int64_t TOCOffset   = 3 * PVT.getStoreSize();
+
+  unsigned BufReg = MI->getOperand(0).getReg();
+
+  // Reload FP (the jumped-to function may not have had a
+  // frame pointer, and if so, then its r31 will be restored
+  // as necessary).
+  if (PVT == MVT::i64) {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LD), FP)
+            .addImm(0)
+            .addReg(BufReg);
+  } else {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LWZ), FP)
+            .addImm(0)
+            .addReg(BufReg);
+  }
+  MIB.setMemRefs(MMOBegin, MMOEnd);
+
+  // Reload IP
+  if (PVT == MVT::i64) {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LD), Tmp)
+            .addImm(LabelOffset / 4)
+            .addReg(BufReg);
+  } else {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LWZ), Tmp)
+            .addImm(LabelOffset)
+            .addReg(BufReg);
+  }
+  MIB.setMemRefs(MMOBegin, MMOEnd);
+
+  // Reload SP
+  if (PVT == MVT::i64) {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LD), SP)
+            .addImm(SPOffset / 4)
+            .addReg(BufReg);
+  } else {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LWZ), SP)
+            .addImm(SPOffset)
+            .addReg(BufReg);
+  }
+  MIB.setMemRefs(MMOBegin, MMOEnd);
+
+  // FIXME: When we also support base pointers, that register must also be
+  // restored here.
+
+  // Reload TOC
+  if (PVT == MVT::i64 && PPCSubTarget.isSVR4ABI()) {
+    MIB = BuildMI(*MBB, MI, DL, TII->get(PPC::LD), PPC::X2)
+            .addImm(TOCOffset / 4)
+            .addReg(BufReg);
+
+    MIB.setMemRefs(MMOBegin, MMOEnd);
+  }
+
+  // Jump
+  BuildMI(*MBB, MI, DL,
+          TII->get(PVT == MVT::i64 ? PPC::MTCTR8 : PPC::MTCTR)).addReg(Tmp);
+  BuildMI(*MBB, MI, DL, TII->get(PVT == MVT::i64 ? PPC::BCTR8 : PPC::BCTR));
+
+  MI->eraseFromParent();
+  return MBB;
+}
+
 MachineBasicBlock *
 PPCTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
                                                MachineBasicBlock *BB) const {
+  if (MI->getOpcode() == PPC::EH_SjLj_SetJmp32 ||
+      MI->getOpcode() == PPC::EH_SjLj_SetJmp64) {
+    return emitEHSjLjSetJmp(MI, BB);
+  } else if (MI->getOpcode() == PPC::EH_SjLj_LongJmp32 ||
+             MI->getOpcode() == PPC::EH_SjLj_LongJmp64) {
+    return emitEHSjLjLongJmp(MI, BB);
+  }
+
   const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
 
   // To "insert" these instructions we actually have to insert their
diff --git a/lib/Target/PowerPC/PPCISelLowering.h b/lib/Target/PowerPC/PPCISelLowering.h
index 8d44d9ff46..1b0427e021 100644
--- a/lib/Target/PowerPC/PPCISelLowering.h
+++ b/lib/Target/PowerPC/PPCISelLowering.h
@@ -16,6 +16,7 @@
 #define LLVM_TARGET_POWERPC_PPC32ISELLOWERING_H
 
 #include "PPC.h"
+#include "PPCRegisterInfo.h"
 #include "PPCSubtarget.h"
 #include "llvm/CodeGen/SelectionDAG.h"
 #include "llvm/Target/TargetLowering.h"
@@ -119,6 +120,12 @@ namespace llvm {
       /// are undefined.
       MFCR,
 
+      // EH_SJLJ_SETJMP - SjLj exception handling setjmp.
+      EH_SJLJ_SETJMP,
+
+      // EH_SJLJ_LONGJMP - SjLj exception handling longjmp.
+      EH_SJLJ_LONGJMP,
+
       /// RESVEC = VCMP(LHS, RHS, OPC) - Represents one of the altivec VCMP*
       /// instructions.  For lack of better number, we use the opcode number
       /// encoding for the OPC field to identify the compare.  For example, 838
@@ -321,6 +328,7 @@ namespace llvm {
 
   class PPCTargetLowering : public TargetLowering {
     const PPCSubtarget &PPCSubTarget;
+    const PPCRegisterInfo *PPCRegInfo;
 
   public:
     explicit PPCTargetLowering(PPCTargetMachine &TM);
@@ -395,6 +403,12 @@ namespace llvm {
                                                 MachineBasicBlock *MBB,
                                             bool is8bit, unsigned Opcode) const;
 
+    MachineBasicBlock *emitEHSjLjSetJmp(MachineInstr *MI,
+                                        MachineBasicBlock *MBB) const;
+
+    MachineBasicBlock *emitEHSjLjLongJmp(MachineInstr *MI,
+                                         MachineBasicBlock *MBB) const;
+
     ConstraintType getConstraintType(const std::string &Constraint) const;
 
     /// Examine constraint string and operand type and determine a weight value.
@@ -608,6 +622,9 @@ namespace llvm {
                      const SmallVectorImpl<ISD::InputArg> &Ins,
                      DebugLoc dl, SelectionDAG &DAG,
                      SmallVectorImpl<SDValue> &InVals) const;
+
+    SDValue lowerEH_SJLJ_SETJMP(SDValue Op, SelectionDAG &DAG) const;
+    SDValue lowerEH_SJLJ_LONGJMP(SDValue Op, SelectionDAG &DAG) const;
   };
 }
 
diff --git a/lib/Target/PowerPC/PPCInstr64Bit.td b/lib/Target/PowerPC/PPCInstr64Bit.td
index f43ed53512..975a7174f6 100644
--- a/lib/Target/PowerPC/PPCInstr64Bit.td
+++ b/lib/Target/PowerPC/PPCInstr64Bit.td
@@ -273,6 +273,19 @@ def MFCR8 : XFXForm_3<31, 19, (outs G8RC:$rT), (ins),
                      "mfcr $rT", SprMFCR>,
                      PPC970_MicroCode, PPC970_Unit_CRU;
 
+let hasSideEffects = 1, isBarrier = 1, isCodeGenOnly = 1,
+    usesCustomInserter = 1 in {
+  def EH_SjLj_SetJmp64  : Pseudo<(outs GPRC:$dst), (ins memr:$buf),
+                            "#EH_SJLJ_SETJMP64",
+                            [(set GPRC:$dst, (PPCeh_sjlj_setjmp addr:$buf))]>,
+                          Requires<[In64BitMode]>;
+  let isTerminator = 1 in
+  def EH_SjLj_LongJmp64 : Pseudo<(outs), (ins memr:$buf),
+                            "#EH_SJLJ_LONGJMP64",
+                            [(PPCeh_sjlj_longjmp addr:$buf)]>,
+                          Requires<[In64BitMode]>;
+}
+
 //===----------------------------------------------------------------------===//
 // 64-bit SPR manipulation instrs.
 
diff --git a/lib/Target/PowerPC/PPCInstrFormats.td b/lib/Target/PowerPC/PPCInstrFormats.td
index c3c171cd21..16dbee5d29 100644
--- a/lib/Target/PowerPC/PPCInstrFormats.td
+++ b/lib/Target/PowerPC/PPCInstrFormats.td
@@ -120,6 +120,18 @@ class BForm_1<bits<6> opcode, bits<5> bo, bit aa, bit lk, dag OOL, dag IOL,
   let CR = 0;
 }
 
+class BForm_2<bits<6> opcode, bits<5> bo, bits<5> bi, bit aa, bit lk,
+              dag OOL, dag IOL, string asmstr>
+  : I<opcode, OOL, IOL, asmstr, BrB> {
+  bits<14> BD;
+
+  let Inst{6-10}  = bo;
+  let Inst{11-15} = bi;
+  let Inst{16-29} = BD;
+  let Inst{30}    = aa;
+  let Inst{31}    = lk;
+}
+
 // 1.7.4 D-Form
 class DForm_base<bits<6> opcode, dag OOL, dag IOL, string asmstr,
                  InstrItinClass itin, list<dag> pattern> 
diff --git a/lib/Target/PowerPC/PPCInstrInfo.td b/lib/Target/PowerPC/PPCInstrInfo.td
index a05ebad41a..84cdb1f39d 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.td
+++ b/lib/Target/PowerPC/PPCInstrInfo.td
@@ -158,6 +158,14 @@ def retflag       : SDNode<"PPCISD::RET_FLAG", SDTNone,
 def PPCtc_return : SDNode<"PPCISD::TC_RETURN", SDT_PPCTC_ret,
                         [SDNPHasChain,  SDNPOptInGlue, SDNPVariadic]>;
 
+def PPCeh_sjlj_setjmp  : SDNode<"PPCISD::EH_SJLJ_SETJMP",
+                                SDTypeProfile<1, 1, [SDTCisInt<0>,
+                                                     SDTCisPtrTy<1>]>,
+                                [SDNPHasChain, SDNPSideEffect]>;
+def PPCeh_sjlj_longjmp : SDNode<"PPCISD::EH_SJLJ_LONGJMP",
+                                SDTypeProfile<0, 1, [SDTCisPtrTy<0>]>,
+                                [SDNPHasChain, SDNPSideEffect]>;
+
 def PPCvcmp       : SDNode<"PPCISD::VCMP" , SDT_PPCvcmp, []>;
 def PPCvcmp_o     : SDNode<"PPCISD::VCMPo", SDT_PPCvcmp, [SDNPOutGlue]>;
 
@@ -391,6 +399,12 @@ def memrix : Operand<iPTR> {   // memri where the imm is shifted 2 bits.
   let EncoderMethod = "getMemRIXEncoding";
 }
 
+// A single-register address. This is used with the SjLj
+// pseudo-instructions.
+def memr : Operand<iPTR> {
+  let MIOperandInfo = (ops ptr_rc:$ptrreg);
+}
+
 // PowerPC Predicate operand.  20 = (0<<5)|20 = always, CR0 is a dummy reg
 // that doesn't matter.
 def pred : PredicateOperand<OtherVT, (ops imm, CRRC),
@@ -404,6 +418,10 @@ def xaddr  : ComplexPattern<iPTR, 2, "SelectAddrIdx",    [], []>;
 def xoaddr : ComplexPattern<iPTR, 2, "SelectAddrIdxOnly",[], []>;
 def ixaddr : ComplexPattern<iPTR, 2, "SelectAddrImmShift", [], []>; // "std"
 
+// The address in a single register. This is used with the SjLj
+// pseudo-instructions.
+def addr   : ComplexPattern<iPTR, 1, "SelectAddr",[], []>;
+
 /// This is just the offset part of iaddr, used for preinc.
 def iaddroff : ComplexPattern<iPTR, 1, "SelectAddrImmOffs", [], []>;
 def xaddroff : ComplexPattern<iPTR, 1, "SelectAddrIdxOffs", [], []>;
@@ -505,6 +523,14 @@ let isBranch = 1, isTerminator = 1, hasCtrlDep = 1, PPC970_Unit = 7 in {
   }
 }
 
+// The direct BCL used by the SjLj setjmp code.
+let isCall = 1, hasCtrlDep = 1, PPC970_Unit = 7 in {
+  let Defs = [LR], Uses = [RM] in {
+    def BCL  : BForm_2<16, 20, 31, 0, 1, (outs), (ins condbrtarget:$dst),
+                       "bcl 20, 31, $dst">;
+  }
+}
+
 // Darwin ABI Calls.
 let isCall = 1, PPC970_Unit = 7, Defs = [LR] in {
   // Convenient aliases for call instructions
@@ -583,6 +609,23 @@ def TAILBA   : IForm<18, 0, 0, (outs), (ins aaddr:$dst),
                   "ba $dst", BrB,
                   []>;
 
+let hasSideEffects = 1, isBarrier = 1, isCodeGenOnly = 1,
+    usesCustomInserter = 1 in {
+  def EH_SjLj_SetJmp32  : Pseudo<(outs GPRC:$dst), (ins memr:$buf),
+                            "#EH_SJLJ_SETJMP32",
+                            [(set GPRC:$dst, (PPCeh_sjlj_setjmp addr:$buf))]>,
+                          Requires<[In32BitMode]>;
+  let isTerminator = 1 in
+  def EH_SjLj_LongJmp32 : Pseudo<(outs), (ins memr:$buf),
+                            "#EH_SJLJ_LONGJMP32",
+                            [(PPCeh_sjlj_longjmp addr:$buf)]>,
+                          Requires<[In32BitMode]>;
+}
+
+let isBranch = 1, isTerminator = 1, isCodeGenOnly = 1 in {
+  def EH_SjLj_Setup : Pseudo<(outs), (ins directbrtarget:$dst),
+                        "#EH_SjLj_Setup\t$dst", []>;
+}
 
 // DCB* instructions.
 def DCBA   : DCB_Form<758, 0, (outs), (ins memrr:$dst),
diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp
index f3ac23184f..150e241161 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.cpp
+++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp
@@ -105,6 +105,18 @@ PPCRegisterInfo::getCallPreservedMask(CallingConv::ID CC) const {
   return Subtarget.isPPC64() ? CSR_SVR464_RegMask : CSR_SVR432_RegMask;
 }
 
+const uint32_t*
+PPCRegisterInfo::getNoPreservedMask() const {
+  // The naming here is inverted: The CSR_NoRegs_Altivec has the
+  // Altivec registers masked so that they're not saved and restored around
+  // instructions with this preserved mask.
+
+  if (!Subtarget.hasAltivec())
+    return CSR_NoRegs_Altivec_RegMask;
+
+  return CSR_NoRegs_RegMask;
+}
+
 BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
   BitVector Reserved(getNumRegs());
   const PPCFrameLowering *PPCFI =
diff --git a/lib/Target/PowerPC/PPCRegisterInfo.h b/lib/Target/PowerPC/PPCRegisterInfo.h
index 1c020ea5c9..ba0fb48b85 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.h
+++ b/lib/Target/PowerPC/PPCRegisterInfo.h
@@ -44,6 +44,7 @@ public:
   /// Code Generation virtual methods...
   const uint16_t *getCalleeSavedRegs(const MachineFunction* MF = 0) const;
   const uint32_t *getCallPreservedMask(CallingConv::ID CC) const;
+  const uint32_t *getNoPreservedMask() const;
 
   BitVector getReservedRegs(const MachineFunction &MF) const;
 
diff --git a/test/CodeGen/PowerPC/sjlj.ll b/test/CodeGen/PowerPC/sjlj.ll
new file mode 100644
index 0000000000..3440b314dd
--- /dev/null
+++ b/test/CodeGen/PowerPC/sjlj.ll
@@ -0,0 +1,108 @@
+; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 | FileCheck %s
+; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mcpu=a2 | FileCheck -check-prefix=CHECK-NOAV %s
+target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+%struct.__jmp_buf_tag = type { [64 x i64], i32, %struct.__sigset_t, [8 x i8] }
+%struct.__sigset_t = type { [16 x i64] }
+
+@env_sigill = internal global [1 x %struct.__jmp_buf_tag] zeroinitializer, align 16
+
+define void @foo() #0 {
+entry:
+  call void @llvm.eh.sjlj.longjmp(i8* bitcast ([1 x %struct.__jmp_buf_tag]* @env_sigill to i8*))
+  unreachable
+
+; CHECK: @foo
+; CHECK: addis [[REG:[0-9]+]], 2, env_sigill@toc@ha
+; CHECK: addi [[REG]], [[REG]], env_sigill@toc@l
+; CHECK: ld 31, 0([[REG]])
+; CHECK: ld [[REG2:[0-9]+]], 8([[REG]])
+; CHECK: ld 1, 16([[REG]])
+; CHECK: mtctr [[REG2]]
+; CHECK: ld 2, 24([[REG]])
+; CHECK: bctr
+
+return:                                           ; No predecessors!
+  ret void
+}
+
+declare void @llvm.eh.sjlj.longjmp(i8*) #1
+
+define signext i32 @main() #0 {
+entry:
+  %retval = alloca i32, align 4
+  store i32 0, i32* %retval
+  %0 = call i8* @llvm.frameaddress(i32 0)
+  store i8* %0, i8** bitcast ([1 x %struct.__jmp_buf_tag]* @env_sigill to i8**)
+  %1 = call i8* @llvm.stacksave()
+  store i8* %1, i8** getelementptr (i8** bitcast ([1 x %struct.__jmp_buf_tag]* @env_sigill to i8**), i32 2)
+  %2 = call i32 @llvm.eh.sjlj.setjmp(i8* bitcast ([1 x %struct.__jmp_buf_tag]* @env_sigill to i8*))
+  %tobool = icmp ne i32 %2, 0
+  br i1 %tobool, label %if.then, label %if.else
+
+if.then:                                          ; preds = %entry
+  store i32 1, i32* %retval
+  br label %return
+
+if.else:                                          ; preds = %entry
+  call void @foo()
+  br label %if.end
+
+if.end:                                           ; preds = %if.else
+  store i32 0, i32* %retval
+  br label %return
+
+return:                                           ; preds = %if.end, %if.then
+  %3 = load i32* %retval
+  ret i32 %3
+
+; CHECK: @main
+; CHECK: std
+; CHECK: stfd
+; CHECK: stvx
+
+; CHECK: addis [[REG:[0-9]+]], 2, env_sigill@toc@ha
+; CHECK: std 31, env_sigill@toc@l([[REG]])
+; CHECK: addi [[REG]], [[REG]], env_sigill@toc@l
+; CHECK: std [[REG]], [[OFF:[0-9]+]](31)                  # 8-byte Folded Spill
+; CHECK: std 1, 16([[REG]])
+; CHECK: std 2, 24([[REG]])
+; CHECK: bcl 20, 31, .LBB1_1
+; CHECK: li 3, 1
+; CHECK: #EH_SjLj_Setup	.LBB1_1
+; CHECK: b .LBB1_2
+
+; CHECK: .LBB1_1:
+; CHECK: mflr [[REGL:[0-9]+]]
+; CHECK: ld [[REG2:[0-9]+]], [[OFF]](31)                   # 8-byte Folded Reload
+; CHECK: std [[REGL]], 8([[REG2]])
+; CHECK: li 3, 0
+
+; CHECK: .LBB1_2:
+
+; CHECK: lfd
+; CHECK: lvx
+; CHECK: ld
+; CHECK: blr
+
+; CHECK-NOAV: @main
+; CHECK-NOAV-NOT: stvx
+; CHECK-NOAV: bcl
+; CHECK-NOAV: mflr
+; CHECK-NOAV: bl foo
+; CHECK-NOAV-NOT: lvx
+; CHECK-NOAV: blr
+}
+
+declare i8* @llvm.frameaddress(i32) #2
+
+declare i8* @llvm.stacksave() #3
+
+declare i32 @llvm.eh.sjlj.setjmp(i8*) #3
+
+attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-frame-pointer-elim-non-leaf"="true" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { noreturn nounwind }
+attributes #2 = { nounwind readnone }
+attributes #3 = { nounwind }
+