[PowerPC] Fix reverted patch r227976 to avoid register assignment issues

See full discussion in http://reviews.llvm.org/D7491.

We now hide the add-immediate and call instructions together in a
separate pseudo-op, which is tagged to define GPR3 and clobber the
call-killed registers.  The PPCTLSDynamicCall pass prior to RA now
expands this op into the two separate addi and call ops, with explicit
definitions of GPR3 on both instructions, and explicit clobbers on the
call instruction.  The pass is now marked as requiring and preserving
the LiveIntervals and SlotIndexes analyses, and fixes these up after
the replacement sequences are introduced.

Self-hosting has been verified on LE P8 and BE P7 with various
optimization levels, etc.  It has also been verified with the
--no-tls-optimize flag workaround removed.

llvm-svn: 228725

1 files changed, 13 insertions, 59 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index ce0573026e8..7ecfac66b49 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -806,8 +806,6 @@ const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
   case PPCISD::SHL:             return "PPCISD::SHL";
   case PPCISD::CALL:            return "PPCISD::CALL";
   case PPCISD::CALL_NOP:        return "PPCISD::CALL_NOP";
-  case PPCISD::CALL_TLS:        return "PPCISD::CALL_TLS";
-  case PPCISD::CALL_NOP_TLS:    return "PPCISD::CALL_NOP_TLS";
   case PPCISD::MTCTR:           return "PPCISD::MTCTR";
   case PPCISD::BCTRL:           return "PPCISD::BCTRL";
   case PPCISD::BCTRL_LOAD_TOC:  return "PPCISD::BCTRL_LOAD_TOC";
@@ -841,8 +839,12 @@ const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
   case PPCISD::ADD_TLS:         return "PPCISD::ADD_TLS";
   case PPCISD::ADDIS_TLSGD_HA:  return "PPCISD::ADDIS_TLSGD_HA";
   case PPCISD::ADDI_TLSGD_L:    return "PPCISD::ADDI_TLSGD_L";
+  case PPCISD::GET_TLS_ADDR:    return "PPCISD::GET_TLS_ADDR";
+  case PPCISD::ADDI_TLSGD_L_ADDR: return "PPCISD::ADDI_TLSGD_L_ADDR";
   case PPCISD::ADDIS_TLSLD_HA:  return "PPCISD::ADDIS_TLSLD_HA";
   case PPCISD::ADDI_TLSLD_L:    return "PPCISD::ADDI_TLSLD_L";
+  case PPCISD::GET_TLSLD_ADDR:  return "PPCISD::GET_TLSLD_ADDR";
+  case PPCISD::ADDI_TLSLD_L_ADDR: return "PPCISD::ADDI_TLSLD_L_ADDR";
   case PPCISD::ADDIS_DTPREL_HA: return "PPCISD::ADDIS_DTPREL_HA";
   case PPCISD::ADDI_DTPREL_L:   return "PPCISD::ADDI_DTPREL_L";
   case PPCISD::VADD_SPLAT:      return "PPCISD::VADD_SPLAT";
@@ -1701,27 +1703,6 @@ SDValue PPCTargetLowering::LowerBlockAddress(SDValue Op,
   return LowerLabelRef(TgtBAHi, TgtBALo, isPIC, DAG);
 }
 
-// Generate a call to __tls_get_addr for the given GOT entry Op.
-std::pair<SDValue,SDValue>
-PPCTargetLowering::lowerTLSCall(SDValue Op, SDLoc dl,
-                                SelectionDAG &DAG) const {
-
-  Type *IntPtrTy = getDataLayout()->getIntPtrType(*DAG.getContext());
-  TargetLowering::ArgListTy Args;
-  TargetLowering::ArgListEntry Entry;
-  Entry.Node = Op;
-  Entry.Ty = IntPtrTy;
-  Args.push_back(Entry);
-
-  TargetLowering::CallLoweringInfo CLI(DAG);
-  CLI.setDebugLoc(dl).setChain(DAG.getEntryNode())
-    .setCallee(CallingConv::C, IntPtrTy,
-               DAG.getTargetExternalSymbol("__tls_get_addr", getPointerTy()),
-               std::move(Args), 0);
-
-  return LowerCallTo(CLI);
-}
-
 SDValue PPCTargetLowering::LowerGlobalTLSAddress(SDValue Op,
                                               SelectionDAG &DAG) const {
 
@@ -1768,8 +1749,7 @@ SDValue PPCTargetLowering::LowerGlobalTLSAddress(SDValue Op,
   }
 
   if (Model == TLSModel::GeneralDynamic) {
-    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
-                                             PPCII::MO_TLSGD);
+    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, 0);
     SDValue GOTPtr;
     if (is64bit) {
       setUsesTOCBasePtr(DAG);
@@ -1782,15 +1762,12 @@ SDValue PPCTargetLowering::LowerGlobalTLSAddress(SDValue Op,
       else
         GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
     }
-    SDValue GOTEntry = DAG.getNode(PPCISD::ADDI_TLSGD_L, dl, PtrVT,
-                                   GOTPtr, TGA);
-    std::pair<SDValue, SDValue> CallResult = lowerTLSCall(GOTEntry, dl, DAG);
-    return CallResult.first;
+    return DAG.getNode(PPCISD::ADDI_TLSGD_L_ADDR, dl, PtrVT,
+                       GOTPtr, TGA, TGA);
   }
 
   if (Model == TLSModel::LocalDynamic) {
-    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
-                                             PPCII::MO_TLSLD);
+    SDValue TGA = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, 0);
     SDValue GOTPtr;
     if (is64bit) {
       setUsesTOCBasePtr(DAG);
@@ -1803,13 +1780,10 @@ SDValue PPCTargetLowering::LowerGlobalTLSAddress(SDValue Op,
       else
         GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
     }
-    SDValue GOTEntry = DAG.getNode(PPCISD::ADDI_TLSLD_L, dl, PtrVT,
-                                   GOTPtr, TGA);
-    std::pair<SDValue, SDValue> CallResult = lowerTLSCall(GOTEntry, dl, DAG);
-    SDValue TLSAddr = CallResult.first;
-    SDValue Chain = CallResult.second;
-    SDValue DtvOffsetHi = DAG.getNode(PPCISD::ADDIS_DTPREL_HA, dl, PtrVT,
-                                      Chain, TLSAddr, TGA);
+    SDValue TLSAddr = DAG.getNode(PPCISD::ADDI_TLSLD_L_ADDR, dl,
+                                  PtrVT, GOTPtr, TGA, TGA);
+    SDValue DtvOffsetHi = DAG.getNode(PPCISD::ADDIS_DTPREL_HA, dl,
+                                      PtrVT, TLSAddr, TGA);
     return DAG.getNode(PPCISD::ADDI_DTPREL_L, dl, PtrVT, DtvOffsetHi, TGA);
   }
 
@@ -3833,23 +3807,6 @@ unsigned PrepareCall(SelectionDAG &DAG, SDValue &Callee, SDValue &InFlag,
   if (Callee.getNode()) {
     Ops.push_back(Chain);
     Ops.push_back(Callee);
-
-    // If this is a call to __tls_get_addr, find the symbol whose address
-    // is to be taken and add it to the list.  This will be used to 
-    // generate __tls_get_addr(<sym>@tlsgd) or __tls_get_addr(<sym>@tlsld).
-    // We find the symbol by walking the chain to the CopyFromReg, walking
-    // back from the CopyFromReg to the ADDI_TLSGD_L or ADDI_TLSLD_L, and
-    // pulling the symbol from that node.
-    if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee))
-      if (!strcmp(S->getSymbol(), "__tls_get_addr")) {
-        assert(!needIndirectCall && "Indirect call to __tls_get_addr???");
-        SDNode *AddI = Chain.getNode()->getOperand(2).getNode();
-        SDValue TGTAddr = AddI->getOperand(1);
-        assert(TGTAddr.getNode()->getOpcode() == ISD::TargetGlobalTLSAddress &&
-               "Didn't find target global TLS address where we expected one");
-        Ops.push_back(TGTAddr);
-        CallOpc = PPCISD::CALL_TLS;
-      }
   }
   // If this is a tail call add stack pointer delta.
   if (isTailCall)
@@ -4012,12 +3969,9 @@ PPCTargetLowering::FinishCall(CallingConv::ID CallConv, SDLoc dl,
       Ops.insert(std::next(Ops.begin()), AddTOC);
     } else if ((CallOpc == PPCISD::CALL) &&
                (!isLocalCall(Callee) ||
-                DAG.getTarget().getRelocationModel() == Reloc::PIC_)) {
+                DAG.getTarget().getRelocationModel() == Reloc::PIC_))
       // Otherwise insert NOP for non-local calls.
       CallOpc = PPCISD::CALL_NOP;
-    } else if (CallOpc == PPCISD::CALL_TLS)
-      // For 64-bit SVR4, TLS calls are always non-local.
-      CallOpc = PPCISD::CALL_NOP_TLS;
   }
 
   Chain = DAG.getNode(CallOpc, dl, NodeTys, Ops);