Refactor to expose RTLIB calls to targets.

Tim Northover · Tim Northover · commit 2c8cf4b404e5 · 2013-01-09T13:18:15.000Z
fp128 is almost but not quite completely illegal as a type on AArch64. As a result it needs to have a register class (for argument passing mainly), but all operations need to be lowered to runtime calls. Currently there's no way for targets to do this (without duplicating code), as the relevant functions are hidden in SelectionDAG. This patch changes that. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171971 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
@@ -1848,6 +1848,17 @@ class TargetLowering {
     return LibcallCallingConvs[Call];
   }
 
+  bool isInTailCallPosition(SelectionDAG &DAG, SDNode *Node,
+                            SDValue &Chain) const;
+
+  void softenSetCCOperands(SelectionDAG &DAG, EVT VT,
+                           SDValue &NewLHS, SDValue &NewRHS,
+                           ISD::CondCode &CCCode, DebugLoc DL) const;
+
+  SDValue makeLibCall(SelectionDAG &DAG, RTLIB::Libcall LC, EVT RetVT,
+                      const SDValue *Ops, unsigned NumOps,
+                      bool isSigned, DebugLoc dl) const;
+
 private:
   const TargetMachine &TM;
   const DataLayout *TD;
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1841,26 +1841,6 @@ SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
   return ExpandVectorBuildThroughStack(Node);
 }
 
-static bool isInTailCallPosition(SelectionDAG &DAG, SDNode *Node,
-                                SDValue &Chain, const TargetLowering &TLI) {
-  const Function *F = DAG.getMachineFunction().getFunction();
-
-  // Conservatively require the attributes of the call to match those of
-  // the return. Ignore noalias because it doesn't affect the call sequence.
-  Attribute CallerRetAttr = F->getAttributes().getRetAttributes();
-  if (AttrBuilder(CallerRetAttr)
-      .removeAttribute(Attribute::NoAlias).hasAttributes())
-    return false;
-
-  // It's not safe to eliminate the sign / zero extension of the return value.
-  if (CallerRetAttr.hasAttribute(Attribute::ZExt) ||
-      CallerRetAttr.hasAttribute(Attribute::SExt))
-    return false;
-
-  // Check if the only use is a function return node.
-  return TLI.isUsedByReturnOnly(Node, Chain);
-}
-
 // ExpandLibCall - Expand a node into a call to a libcall.  If the result value
 // does not fit into a register, return the lo part and set the hi part to the
 // by-reg argument.  If it does fit into a single register, return the result
@@ -1891,7 +1871,7 @@ SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
   // isTailCall may be true since the callee does not reference caller stack
   // frame. Check if it's in the right position.
   SDValue TCChain = InChain;
-  bool isTailCall = isInTailCallPosition(DAG, Node, TCChain, TLI);
+  bool isTailCall = TLI.isInTailCallPosition(DAG, Node, TCChain);
   if (isTailCall)
     InChain = TCChain;
 
diff --git a/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
diff --git a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -1767,7 +1767,8 @@ void DAGTypeLegalizer::ExpandIntRes_FP_TO_SINT(SDNode *N, SDValue &Lo,
   SDValue Op = N->getOperand(0);
   RTLIB::Libcall LC = RTLIB::getFPTOSINT(Op.getValueType(), VT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unexpected fp-to-sint conversion!");
-  SplitInteger(MakeLibCall(LC, VT, &Op, 1, true/*irrelevant*/, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, &Op, 1, true/*irrelevant*/, dl),
+               Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_FP_TO_UINT(SDNode *N, SDValue &Lo,
@@ -1777,7 +1778,8 @@ void DAGTypeLegalizer::ExpandIntRes_FP_TO_UINT(SDNode *N, SDValue &Lo,
   SDValue Op = N->getOperand(0);
   RTLIB::Libcall LC = RTLIB::getFPTOUINT(Op.getValueType(), VT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unexpected fp-to-uint conversion!");
-  SplitInteger(MakeLibCall(LC, VT, &Op, 1, false/*irrelevant*/, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, &Op, 1, false/*irrelevant*/, dl),
+               Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_LOAD(LoadSDNode *N,
@@ -1992,7 +1994,8 @@ void DAGTypeLegalizer::ExpandIntRes_MUL(SDNode *N,
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported MUL!");
 
   SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-  SplitInteger(MakeLibCall(LC, VT, Ops, 2, true/*irrelevant*/, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, true/*irrelevant*/, dl),
+               Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_SADDSUBO(SDNode *Node,
@@ -2054,7 +2057,7 @@ void DAGTypeLegalizer::ExpandIntRes_SDIV(SDNode *N,
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported SDIV!");
 
   SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-  SplitInteger(MakeLibCall(LC, VT, Ops, 2, true, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, true, dl), Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_Shift(SDNode *N,
@@ -2138,7 +2141,7 @@ void DAGTypeLegalizer::ExpandIntRes_Shift(SDNode *N,
 
   if (LC != RTLIB::UNKNOWN_LIBCALL && TLI.getLibcallName(LC)) {
     SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-    SplitInteger(MakeLibCall(LC, VT, Ops, 2, isSigned, dl), Lo, Hi);
+    SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, isSigned, dl), Lo, Hi);
     return;
   }
 
@@ -2221,7 +2224,7 @@ void DAGTypeLegalizer::ExpandIntRes_SREM(SDNode *N,
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported SREM!");
 
   SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-  SplitInteger(MakeLibCall(LC, VT, Ops, 2, true, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, true, dl), Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_TRUNCATE(SDNode *N,
@@ -2361,7 +2364,7 @@ void DAGTypeLegalizer::ExpandIntRes_UDIV(SDNode *N,
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported UDIV!");
 
   SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-  SplitInteger(MakeLibCall(LC, VT, Ops, 2, false, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, false, dl), Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_UREM(SDNode *N,
@@ -2381,7 +2384,7 @@ void DAGTypeLegalizer::ExpandIntRes_UREM(SDNode *N,
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported UREM!");
 
   SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-  SplitInteger(MakeLibCall(LC, VT, Ops, 2, false, dl), Lo, Hi);
+  SplitInteger(TLI.makeLibCall(DAG, LC, VT, Ops, 2, false, dl), Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandIntRes_ZERO_EXTEND(SDNode *N,
@@ -2668,7 +2671,7 @@ SDValue DAGTypeLegalizer::ExpandIntOp_SINT_TO_FP(SDNode *N) {
   RTLIB::Libcall LC = RTLIB::getSINTTOFP(Op.getValueType(), DstVT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL &&
          "Don't know how to expand this SINT_TO_FP!");
-  return MakeLibCall(LC, DstVT, &Op, 1, true, N->getDebugLoc());
+  return TLI.makeLibCall(DAG, LC, DstVT, &Op, 1, true, N->getDebugLoc());
 }
 
 SDValue DAGTypeLegalizer::ExpandIntOp_STORE(StoreSDNode *N, unsigned OpNo) {
@@ -2846,7 +2849,7 @@ SDValue DAGTypeLegalizer::ExpandIntOp_UINT_TO_FP(SDNode *N) {
   RTLIB::Libcall LC = RTLIB::getUINTTOFP(SrcVT, DstVT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL &&
          "Don't know how to expand this UINT_TO_FP!");
-  return MakeLibCall(LC, DstVT, &Op, 1, true, dl);
+  return TLI.makeLibCall(DAG, LC, DstVT, &Op, 1, true, dl);
 }
 
 SDValue DAGTypeLegalizer::ExpandIntOp_ATOMIC_STORE(SDNode *N) {
diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
@@ -1020,50 +1020,20 @@ SDValue DAGTypeLegalizer::LibCallify(RTLIB::Libcall LC, SDNode *N,
   unsigned NumOps = N->getNumOperands();
   DebugLoc dl = N->getDebugLoc();
   if (NumOps == 0) {
-    return MakeLibCall(LC, N->getValueType(0), 0, 0, isSigned, dl);
+    return TLI.makeLibCall(DAG, LC, N->getValueType(0), 0, 0, isSigned, dl);
   } else if (NumOps == 1) {
     SDValue Op = N->getOperand(0);
-    return MakeLibCall(LC, N->getValueType(0), &Op, 1, isSigned, dl);
+    return TLI.makeLibCall(DAG, LC, N->getValueType(0), &Op, 1, isSigned, dl);
   } else if (NumOps == 2) {
     SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) };
-    return MakeLibCall(LC, N->getValueType(0), Ops, 2, isSigned, dl);
+    return TLI.makeLibCall(DAG, LC, N->getValueType(0), Ops, 2, isSigned, dl);
   }
   SmallVector<SDValue, 8> Ops(NumOps);
   for (unsigned i = 0; i < NumOps; ++i)
     Ops[i] = N->getOperand(i);
 
-  return MakeLibCall(LC, N->getValueType(0), &Ops[0], NumOps, isSigned, dl);
-}
-
-/// MakeLibCall - Generate a libcall taking the given operands as arguments and
-/// returning a result of type RetVT.
-SDValue DAGTypeLegalizer::MakeLibCall(RTLIB::Libcall LC, EVT RetVT,
-                                      const SDValue *Ops, unsigned NumOps,
-                                      bool isSigned, DebugLoc dl) {
-  TargetLowering::ArgListTy Args;
-  Args.reserve(NumOps);
-
-  TargetLowering::ArgListEntry Entry;
-  for (unsigned i = 0; i != NumOps; ++i) {
-    Entry.Node = Ops[i];
-    Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext());
-    Entry.isSExt = isSigned;
-    Entry.isZExt = !isSigned;
-    Args.push_back(Entry);
-  }
-  SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
-                                         TLI.getPointerTy());
-
-  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
-  TargetLowering::
-  CallLoweringInfo CLI(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
-                    false, 0, TLI.getLibcallCallingConv(LC),
-                    /*isTailCall=*/false,
-                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
-                    Callee, Args, DAG, dl);
-  std::pair<SDValue,SDValue> CallInfo = TLI.LowerCallTo(CLI);
-
-  return CallInfo.first;
+  return TLI.makeLibCall(DAG, LC, N->getValueType(0),
+                         &Ops[0], NumOps, isSigned, dl);
 }
 
 // ExpandChainLibCall - Expand a node into a call to a libcall. Similar to
diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/lib/CodeGen/SelectionDAG/LegalizeTypes.h
@@ -159,9 +159,6 @@ class LLVM_LIBRARY_VISIBILITY DAGTypeLegalizer {
   SDValue GetVectorElementPointer(SDValue VecPtr, EVT EltVT, SDValue Index);
   SDValue JoinIntegers(SDValue Lo, SDValue Hi);
   SDValue LibCallify(RTLIB::Libcall LC, SDNode *N, bool isSigned);
-  SDValue MakeLibCall(RTLIB::Libcall LC, EVT RetVT,
-                      const SDValue *Ops, unsigned NumOps, bool isSigned,
-                      DebugLoc dl);
   
   std::pair<SDValue, SDValue> ExpandChainLibCall(RTLIB::Libcall LC,
                                                  SDNode *Node, bool isSigned);
@@ -433,9 +430,6 @@ class LLVM_LIBRARY_VISIBILITY DAGTypeLegalizer {
   SDValue SoftenFloatOp_SETCC(SDNode *N);
   SDValue SoftenFloatOp_STORE(SDNode *N, unsigned OpNo);
 
-  void SoftenSetCCOperands(SDValue &NewLHS, SDValue &NewRHS,
-                           ISD::CondCode &CCCode, DebugLoc dl);
-
   //===--------------------------------------------------------------------===//
   // Float Expansion Support: LegalizeFloatTypes.cpp
   //===--------------------------------------------------------------------===//
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -1012,6 +1012,161 @@ MVT::SimpleValueType TargetLowering::getCmpLibcallReturnType() const {
   return MVT::i32; // return the default value
 }
 
+/// Check whether a given call node is in tail position within its function. If
+/// so, it sets Chain to the input chain of the tail call.
+bool TargetLowering::isInTailCallPosition(SelectionDAG &DAG, SDNode *Node,
+                                          SDValue &Chain) const {
+  const Function *F = DAG.getMachineFunction().getFunction();
+
+  // Conservatively require the attributes of the call to match those of
+  // the return. Ignore noalias because it doesn't affect the call sequence.
+  Attribute CallerRetAttr = F->getAttributes().getRetAttributes();
+  if (AttrBuilder(CallerRetAttr)
+      .removeAttribute(Attribute::NoAlias).hasAttributes())
+    return false;
+
+  // It's not safe to eliminate the sign / zero extension of the return value.
+  if (CallerRetAttr.hasAttribute(Attribute::ZExt) ||
+      CallerRetAttr.hasAttribute(Attribute::SExt))
+    return false;
+
+  // Check if the only use is a function return node.
+  return isUsedByReturnOnly(Node, Chain);
+}
+
+
+/// Generate a libcall taking the given operands as arguments and returning a
+/// result of type RetVT.
+SDValue TargetLowering::makeLibCall(SelectionDAG &DAG,
+                                    RTLIB::Libcall LC, EVT RetVT,
+                                    const SDValue *Ops, unsigned NumOps,
+                                    bool isSigned, DebugLoc dl) const {
+  TargetLowering::ArgListTy Args;
+  Args.reserve(NumOps);
+
+  TargetLowering::ArgListEntry Entry;
+  for (unsigned i = 0; i != NumOps; ++i) {
+    Entry.Node = Ops[i];
+    Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext());
+    Entry.isSExt = isSigned;
+    Entry.isZExt = !isSigned;
+    Args.push_back(Entry);
+  }
+  SDValue Callee = DAG.getExternalSymbol(getLibcallName(LC), getPointerTy());
+
+  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
+  TargetLowering::
+  CallLoweringInfo CLI(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
+                    false, 0, getLibcallCallingConv(LC),
+                    /*isTailCall=*/false,
+                    /*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
+                    Callee, Args, DAG, dl);
+  std::pair<SDValue,SDValue> CallInfo = LowerCallTo(CLI);
+
+  return CallInfo.first;
+}
+
+
+/// SoftenSetCCOperands - Soften the operands of a comparison.  This code is
+/// shared among BR_CC, SELECT_CC, and SETCC handlers.
+void TargetLowering::softenSetCCOperands(SelectionDAG &DAG, EVT VT,
+                                         SDValue &NewLHS, SDValue &NewRHS,
+                                         ISD::CondCode &CCCode,
+                                         DebugLoc dl) const {
+  assert((VT == MVT::f32 || VT == MVT::f64 || VT == MVT::f128)
+         && "Unsupported setcc type!");
+
+  // Expand into one or more soft-fp libcall(s).
+  RTLIB::Libcall LC1 = RTLIB::UNKNOWN_LIBCALL, LC2 = RTLIB::UNKNOWN_LIBCALL;
+  switch (CCCode) {
+  case ISD::SETEQ:
+  case ISD::SETOEQ:
+    LC1 = (VT == MVT::f32) ? RTLIB::OEQ_F32 :
+          (VT == MVT::f64) ? RTLIB::OEQ_F64 : RTLIB::OEQ_F128;
+    break;
+  case ISD::SETNE:
+  case ISD::SETUNE:
+    LC1 = (VT == MVT::f32) ? RTLIB::UNE_F32 :
+          (VT == MVT::f64) ? RTLIB::UNE_F64 : RTLIB::UNE_F128;
+    break;
+  case ISD::SETGE:
+  case ISD::SETOGE:
+    LC1 = (VT == MVT::f32) ? RTLIB::OGE_F32 :
+          (VT == MVT::f64) ? RTLIB::OGE_F64 : RTLIB::OGE_F128;
+    break;
+  case ISD::SETLT:
+  case ISD::SETOLT:
+    LC1 = (VT == MVT::f32) ? RTLIB::OLT_F32 :
+          (VT == MVT::f64) ? RTLIB::OLT_F64 : RTLIB::OLT_F128;
+    break;
+  case ISD::SETLE:
+  case ISD::SETOLE:
+    LC1 = (VT == MVT::f32) ? RTLIB::OLE_F32 :
+          (VT == MVT::f64) ? RTLIB::OLE_F64 : RTLIB::OLE_F128;
+    break;
+  case ISD::SETGT:
+  case ISD::SETOGT:
+    LC1 = (VT == MVT::f32) ? RTLIB::OGT_F32 :
+          (VT == MVT::f64) ? RTLIB::OGT_F64 : RTLIB::OGT_F128;
+    break;
+  case ISD::SETUO:
+    LC1 = (VT == MVT::f32) ? RTLIB::UO_F32 :
+          (VT == MVT::f64) ? RTLIB::UO_F64 : RTLIB::UO_F128;
+    break;
+  case ISD::SETO:
+    LC1 = (VT == MVT::f32) ? RTLIB::O_F32 :
+          (VT == MVT::f64) ? RTLIB::O_F64 : RTLIB::O_F128;
+    break;
+  default:
+    LC1 = (VT == MVT::f32) ? RTLIB::UO_F32 :
+          (VT == MVT::f64) ? RTLIB::UO_F64 : RTLIB::UO_F128;
+    switch (CCCode) {
+    case ISD::SETONE:
+      // SETONE = SETOLT | SETOGT
+      LC1 = (VT == MVT::f32) ? RTLIB::OLT_F32 :
+            (VT == MVT::f64) ? RTLIB::OLT_F64 : RTLIB::OLT_F128;
+      // Fallthrough
+    case ISD::SETUGT:
+      LC2 = (VT == MVT::f32) ? RTLIB::OGT_F32 :
+            (VT == MVT::f64) ? RTLIB::OGT_F64 : RTLIB::OGT_F128;
+      break;
+    case ISD::SETUGE:
+      LC2 = (VT == MVT::f32) ? RTLIB::OGE_F32 :
+            (VT == MVT::f64) ? RTLIB::OGE_F64 : RTLIB::OGE_F128;
+      break;
+    case ISD::SETULT:
+      LC2 = (VT == MVT::f32) ? RTLIB::OLT_F32 :
+            (VT == MVT::f64) ? RTLIB::OLT_F64 : RTLIB::OLT_F128;
+      break;
+    case ISD::SETULE:
+      LC2 = (VT == MVT::f32) ? RTLIB::OLE_F32 :
+            (VT == MVT::f64) ? RTLIB::OLE_F64 : RTLIB::OLE_F128;
+      break;
+    case ISD::SETUEQ:
+      LC2 = (VT == MVT::f32) ? RTLIB::OEQ_F32 :
+            (VT == MVT::f64) ? RTLIB::OEQ_F64 : RTLIB::OEQ_F128;
+      break;
+    default: llvm_unreachable("Do not know how to soften this setcc!");
+    }
+  }
+
+  // Use the target specific return value for comparions lib calls.
+  EVT RetVT = getCmpLibcallReturnType();
+  SDValue Ops[2] = { NewLHS, NewRHS };
+  NewLHS = makeLibCall(DAG, LC1, RetVT, Ops, 2, false/*sign irrelevant*/, dl);
+  NewRHS = DAG.getConstant(0, RetVT);
+  CCCode = getCmpLibcallCC(LC1);
+  if (LC2 != RTLIB::UNKNOWN_LIBCALL) {
+    SDValue Tmp = DAG.getNode(ISD::SETCC, dl, getSetCCResultType(RetVT),
+                              NewLHS, NewRHS, DAG.getCondCode(CCCode));
+    NewLHS = makeLibCall(DAG, LC2, RetVT, Ops, 2, false/*sign irrelevant*/, dl);
+    NewLHS = DAG.getNode(ISD::SETCC, dl, getSetCCResultType(RetVT), NewLHS,
+                         NewRHS, DAG.getCondCode(getCmpLibcallCC(LC2)));
+    NewLHS = DAG.getNode(ISD::OR, dl, Tmp.getValueType(), Tmp, NewLHS);
+    NewRHS = SDValue();
+  }
+}
+
 /// getVectorTypeBreakdown - Vector types are broken down into some number of
 /// legal first class types.  For example, MVT::v8f32 maps to 2 MVT::v4f32
 /// with Altivec or SSE1, or 8 promoted MVT::f64 values with the X86 FP stack.
