- Prevent some functions from being inlined to eliminate the code size bloat

  introduced by previous commit.
- SelectCode now returns a SDNode*. If it is not null, the selected node
  produces the same number of results as the input node. The seletion loop
  is responsible for calling ReplaceAllUsesWith() to replace the input node
  with the output target node. For other cases, e.g. when load is folded,
  the selection code is responsible for calling ReplaceAllUsesOfValueWith()
  and SelectCode returns NULL.
- Other clean ups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29602 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 96 insertions, 67 deletions

diff --git a/utils/TableGen/DAGISelEmitter.cpp b/utils/TableGen/DAGISelEmitter.cpp
index 8a88701..bcc192f 100644
--- a/utils/TableGen/DAGISelEmitter.cpp
+++ b/utils/TableGen/DAGISelEmitter.cpp
@@ -2397,7 +2397,7 @@ public:
   /// EmitResultCode - Emit the action for a pattern.  Now that it has matched
   /// we actually have to build a DAG!
   std::pair<unsigned, unsigned>
-  EmitResultCode(TreePatternNode *N, bool LikeLeaf = false,
+  EmitResultCode(TreePatternNode *N, bool &RetSelected, bool LikeLeaf = false,
                  bool isRoot = false) {
     // This is something selected from the pattern we matched.
     if (!N->getName().empty()) {
@@ -2489,7 +2489,7 @@ public:
           if (isRoot && N->isLeaf()) {
             emitCode("ReplaceUses(N, Tmp" + utostr(ResNo) + ");");
             emitCode("Result = Tmp" + utostr(ResNo) + ";");
-            emitCode("return;");
+            emitCode("return NULL;");
           }
         }
       }
@@ -2590,7 +2590,8 @@ public:
       for (unsigned i = 0, e = EmitOrder.size(); i != e; ++i) {
         unsigned OpOrder       = EmitOrder[i].first;
         TreePatternNode *Child = EmitOrder[i].second;
-        std::pair<unsigned, unsigned> NumTemp =  EmitResultCode(Child);
+        std::pair<unsigned, unsigned> NumTemp = 
+          EmitResultCode(Child, RetSelected);
         NumTemps[OpOrder] = NumTemp;
       }
 
@@ -2703,10 +2704,7 @@ public:
         if (!isRoot)
           return std::make_pair(1, ResNo);
 
-        for (unsigned i = 0; i < NumResults; i++)
-          emitCode("ReplaceUses(SDOperand(N.Val, " +
-                   utostr(i) + "), SDOperand(ResNode, " + utostr(i) + "));");
-
+        bool NeedReplace = false;
         if (NodeHasOutFlag)
           emitCode("InFlag = SDOperand(ResNode, " + 
                    utostr(NumResults + (unsigned)NodeHasChain) + ");");
@@ -2716,11 +2714,6 @@ public:
           NumResults = 1;
         }
 
-        if (InputHasChain)
-          emitCode("ReplaceUses(SDOperand(N.Val, " + 
-                   utostr(PatResults) + "), SDOperand(" + ChainName + ".Val, " +
-                   ChainName + ".ResNo" + "));");
-
         if (FoldedChains.size() > 0) {
           std::string Code;
           for (unsigned j = 0, e = FoldedChains.size(); j < e; j++)
@@ -2728,37 +2721,64 @@ public:
                      FoldedChains[j].first + ".Val, " + 
                      utostr(FoldedChains[j].second) + "), SDOperand(ResNode, " +
                      utostr(NumResults) + "));");
+          NeedReplace = true;
         }
 
-        if (NodeHasOutFlag)
+        if (NodeHasOutFlag) {
           emitCode("ReplaceUses(SDOperand(N.Val, " +
                    utostr(PatResults + (unsigned)InputHasChain) +"), InFlag);");
+          NeedReplace = true;
+        }
+
+        if (NeedReplace) {
+          for (unsigned i = 0; i < NumResults; i++)
+            emitCode("ReplaceUses(SDOperand(N.Val, " +
+                     utostr(i) + "), SDOperand(ResNode, " + utostr(i) + "));");
+          if (InputHasChain)
+            emitCode("ReplaceUses(SDOperand(N.Val, " + 
+                     utostr(PatResults) + "), SDOperand(" + ChainName + ".Val, " +
+                     ChainName + ".ResNo" + "));");
+        } else {
+          RetSelected = true;
+        }
 
         // User does not expect the instruction would produce a chain!
-        bool AddedChain = NodeHasChain && !InputHasChain;
-        if (AddedChain && NodeHasOutFlag) {
+        if ((!InputHasChain && NodeHasChain) && NodeHasOutFlag) {
           if (PatResults == 0) {
             emitCode("Result = SDOperand(ResNode, N.ResNo+1);");
           } else {
-            emitCode("if (N.ResNo < " + utostr(PatResults) + ")");
-            emitCode("  Result = SDOperand(ResNode, N.ResNo);");
-            emitCode("else");
-            emitCode("  Result = SDOperand(ResNode, N.ResNo+1);");
+	    assert(PatResults == 1);
+            emitCode("Result = (N.ResNo == 0) ? SDOperand(ResNode, 0) :"
+		     " SDOperand(ResNode, 1);");
           }
         } else if (InputHasChain && !NodeHasChain) {
           // One of the inner node produces a chain.
-          emitCode("if (N.ResNo < " + utostr(PatResults) + ")");
-          emitCode("  Result = SDOperand(ResNode, N.ResNo);");
           if (NodeHasOutFlag) {
-            emitCode("else if (N.ResNo > " + utostr(PatResults) + ")");
-            emitCode("  Result = SDOperand(ResNode, N.ResNo-1);");
-          }
-          emitCode("else");
-          emitCode("  Result = SDOperand(" + ChainName + ".Val, " +
-                   ChainName + ".ResNo);");
-        } else {
+            emitCode("Result = (N.ResNo < " + utostr(PatResults) +
+		     ") ? SDOperand(ResNode, N.ResNo) : " +
+		     "(N.ResNo > " + utostr(PatResults) + ") ? " +
+		     "SDOperand(ResNode, N.ResNo-1) : " + ChainName + "));");
+	    emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(PatResults+1) +
+		     "), SDOperand(ResNode, N.ResNo-1));");
+	  } else {
+            emitCode("Result = (N.ResNo < " + utostr(PatResults) +
+		     ") ? SDOperand(ResNode, N.ResNo) : " +
+		     ChainName + ";");
+	  }
+	  for (unsigned i = 0; i < PatResults; ++i)
+	    emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(i) +
+		     "), SDOperand(ResNode, " + utostr(i) + "));");
+	  emitCode("ReplaceUses(SDOperand(N.Val, " + utostr(PatResults) +
+		   "), " + ChainName + ");");
+	  RetSelected = false;
+	} else {
           emitCode("Result = SDOperand(ResNode, N.ResNo);");
         }
+
+	if (RetSelected)
+	  emitCode("return Result.Val;");
+	else
+	  emitCode("return NULL;");
       } else {
         // If this instruction is the root, and if there is only one use of it,
         // use SelectNodeTo instead of getTargetNode to avoid an allocation.
@@ -2774,6 +2794,8 @@ public:
         if (NodeHasInFlag || HasImpInputs)
           Code += ", InFlag";
         emitCode(Code + ");");
+        if (isRoot)
+          emitCode("  return NULL;");
         emitCode("} else {");
         emitDecl("ResNode", 1);
         Code = "  ResNode = CurDAG->getTargetNode(Opc" + utostr(OpcNo);
@@ -2789,27 +2811,26 @@ public:
         if (NodeHasInFlag || HasImpInputs)
           Code += ", InFlag";
         emitCode(Code + ");");
-        emitCode("  ReplaceUses(N, SDOperand(ResNode, 0));");
         emitCode("  Result = SDOperand(ResNode, 0);");
+        if (isRoot)
+          emitCode("  return Result.Val;");
         emitCode("}");
       }
 
-      if (isRoot)
-        emitCode("return;");
       return std::make_pair(1, ResNo);
     } else if (Op->isSubClassOf("SDNodeXForm")) {
       assert(N->getNumChildren() == 1 && "node xform should have one child!");
       // PatLeaf node - the operand may or may not be a leaf node. But it should
       // behave like one.
-      unsigned OpVal = EmitResultCode(N->getChild(0), true).second;
+      unsigned OpVal = EmitResultCode(N->getChild(0), RetSelected, true).second;
       unsigned ResNo = TmpNo++;
       emitDecl("Tmp" + utostr(ResNo));
       emitCode("Tmp" + utostr(ResNo) + " = Transform_" + Op->getName()
                + "(Tmp" + utostr(OpVal) + ".Val);");
       if (isRoot) {
-        emitCode("ReplaceUses(N, Tmp" + utostr(ResNo) + ");");
+        //emitCode("ReplaceUses(N, Tmp" + utostr(ResNo) + ");");
         emitCode("Result = Tmp" + utostr(ResNo) + ";");
-        emitCode("return;");
+        emitCode("return Result.Val;");
       }
       return std::make_pair(1, ResNo);
     } else {
@@ -2948,7 +2969,8 @@ void DAGISelEmitter::GenerateCodeForPattern(PatternToMatch &Pattern,
 
   // Emit the matcher, capturing named arguments in VariableMap.
   bool FoundChain = false;
-  Emitter.EmitMatchCode(Pattern.getSrcPattern(), NULL, "N", "", "", FoundChain);
+  Emitter.EmitMatchCode(Pattern.getSrcPattern(), NULL, "N", "", "",
+                        FoundChain);
 
   // TP - Get *SOME* tree pattern, we don't care which.
   TreePattern &TP = *PatternFragments.begin()->second;
@@ -2986,7 +3008,8 @@ void DAGISelEmitter::GenerateCodeForPattern(PatternToMatch &Pattern,
     // otherwise we are done.
   } while (Emitter.InsertOneTypeCheck(Pat, Pattern.getSrcPattern(), "N", true));
 
-  Emitter.EmitResultCode(Pattern.getDstPattern(), false, true /*the root*/);
+  bool RetSelected = false;
+  Emitter.EmitResultCode(Pattern.getDstPattern(), RetSelected, false, true);
   delete Pat;
 }
 
@@ -3339,14 +3362,13 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
         } else {
           EmitFuncNum = EmitFunctions.size();
           EmitFunctions.insert(std::make_pair(CalleeCode, EmitFuncNum));
-          OS << "void " << "Emit_" << utostr(EmitFuncNum) << CalleeCode;
+          OS << "SDNode *Emit_" << utostr(EmitFuncNum) << CalleeCode;
         }
 
         // Replace the emission code within selection routines with calls to the
         // emission functions.
-        CallerCode = "Emit_" + utostr(EmitFuncNum) + CallerCode;
+        CallerCode = "return Emit_" + utostr(EmitFuncNum) + CallerCode;
         GeneratedCode.push_back(std::make_pair(false, CallerCode));
-        GeneratedCode.push_back(std::make_pair(false, "return;"));
       }
 
       // Print function.
@@ -3361,7 +3383,7 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
       } else
         OpVTI->second.push_back(OpVTStr);
 
-      OS << "void Select_" << OpName << (OpVTStr != "" ? "_" : "")
+      OS << "SDNode *Select_" << OpName << (OpVTStr != "" ? "_" : "")
          << OpVTStr << "(SDOperand &Result, const SDOperand &N) {\n";    
 
       // Print all declarations.
@@ -3403,14 +3425,15 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
             "Intrinsic::getName((Intrinsic::ID)iid);\n";
         }
         OS << "  std::cerr << '\\n';\n"
-           << "  abort();\n";
+           << "  abort();\n"
+           << "  return NULL;\n";
       }
       OS << "}\n\n";
     }
   }
   
   // Emit boilerplate.
-  OS << "void Select_INLINEASM(SDOperand& Result, SDOperand N) {\n"
+  OS << "SDNode *Select_INLINEASM(SDOperand& Result, SDOperand N) {\n"
      << "  std::vector<SDOperand> Ops(N.Val->op_begin(), N.Val->op_end());\n"
      << "  AddToQueue(Ops[0], N.getOperand(0)); // Select the chain.\n\n"
      << "  // Select the flag operand.\n"
@@ -3422,19 +3445,17 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
      << "  VTs.push_back(MVT::Flag);\n"
      << "  SDOperand New = CurDAG->getNode(ISD::INLINEASM, VTs, &Ops[0], "
                  "Ops.size());\n"
-     << "  ReplaceUses(SDOperand(N.Val, 0), New);\n"
-     << "  ReplaceUses(SDOperand(N.Val, 1), SDOperand(New.Val, 1));\n"
      << "  Result = New.getValue(N.ResNo);\n"
-     << "  return;\n"
+     << "  return Result.Val;\n"
      << "}\n\n";
   
   OS << "// The main instruction selector code.\n"
-     << "void SelectCode(SDOperand &Result, SDOperand N) {\n"
+     << "SDNode *SelectCode(SDOperand &Result, SDOperand N) {\n"
      << "  if (N.getOpcode() >= ISD::BUILTIN_OP_END &&\n"
      << "      N.getOpcode() < (ISD::BUILTIN_OP_END+" << InstNS
      << "INSTRUCTION_LIST_END)) {\n"
      << "    Result = N;\n"
-     << "    return;   // Already selected.\n"
+     << "    return NULL;   // Already selected.\n"
      << "  }\n\n"
      << "  switch (N.getOpcode()) {\n"
      << "  default: break;\n"
@@ -3448,13 +3469,13 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
      << "  case ISD::TargetJumpTable:\n"
      << "  case ISD::TargetGlobalAddress: {\n"
      << "    Result = N;\n"
-     << "    return;\n"
+     << "    return NULL;\n"
      << "  }\n"
      << "  case ISD::AssertSext:\n"
      << "  case ISD::AssertZext: {\n"
      << "    AddToQueue(Result, N.getOperand(0));\n"
      << "    ReplaceUses(N, Result);\n"
-     << "    return;\n"
+     << "    return NULL;\n"
      << "  }\n"
      << "  case ISD::TokenFactor:\n"
      << "  case ISD::CopyFromReg:\n"
@@ -3464,9 +3485,9 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
      << "      AddToQueue(Dummy, N.getOperand(i));\n"
      << "    }\n"
      << "    Result = N;\n"
-     << "    return;\n"
+     << "    return NULL;\n"
      << "  }\n"
-     << "  case ISD::INLINEASM:  Select_INLINEASM(Result, N); return;\n";
+     << "  case ISD::INLINEASM:  return Select_INLINEASM(Result, N);\n";
 
     
   // Loop over all of the case statements, emiting a call to each method we
@@ -3485,7 +3506,7 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
     OS << "  case " << OpcodeInfo.getEnumName() << ": {\n";
     if (OpVTs.size() == 1) {
       std::string &VTStr = OpVTs[0];
-      OS << "    Select_" << OpName
+      OS << "    return Select_" << OpName
          << (VTStr != "" ? "_" : "") << VTStr << "(Result, N);\n";
     } else {
       if (OpcodeInfo.getNumResults())
@@ -3496,26 +3517,26 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
       else
         OS << "    MVT::ValueType NVT = (N.getNumOperands() > 0) ?"
            << " N.getOperand(0).Val->getValueType(0) : MVT::isVoid;\n";
-      int ElseCase = -1;
-      bool First = true;
+      int Default = -1;
+      OS << "    switch (NVT) {\n";
       for (unsigned i = 0, e = OpVTs.size(); i < e; ++i) {
         std::string &VTStr = OpVTs[i];
         if (VTStr == "") {
-          ElseCase = i;
+          Default = i;
           continue;
         }
-        OS << (First ? "    if" : "    else if")
-           << " (NVT == MVT::" << VTStr << ")\n"
-           << "      Select_" << OpName
+        OS << "    case MVT::" << VTStr << ":\n"
+           << "      return Select_" << OpName
            << "_" << VTStr << "(Result, N);\n";
-        First = false;
       }
-      if (ElseCase != -1)
-        OS << "    else\n" << "      Select_" << OpName << "(Result, N);\n";
+      OS << "    default:\n";
+      if (Default != -1)
+        OS << "      return Select_" << OpName << "(Result, N);\n";
       else
-        OS << "    else\n" << "      break;\n";
+	OS << "      break;\n";
+      OS << "    }\n";
+      OS << "    break;\n";
     }
-    OS << "    return;\n";
     OS << "  }\n";
   }
 
@@ -3533,6 +3554,7 @@ void DAGISelEmitter::EmitInstructionSelector(std::ostream &OS) {
      << "  }\n"
      << "  std::cerr << '\\n';\n"
      << "  abort();\n"
+     << "  return NULL;\n"
      << "}\n";
 }
 
@@ -3582,7 +3604,7 @@ void DAGISelEmitter::run(std::ostream &OS) {
   OS << "  return ISelSelected[Id / 8] & (1 << (Id % 8));\n";
   OS << "}\n\n";
 
-  OS << "inline void AddToQueue(SDOperand &Result, SDOperand N) {\n";
+  OS << "void AddToQueue(SDOperand &Result, SDOperand N) NOINLINE {\n";
   OS << "  Result = N;\n";
   OS << "  int Id = N.Val->getNodeId();\n";
   OS << "  if (Id != -1 && !isQueued(Id)) {\n";
@@ -3604,10 +3626,15 @@ OS << "  unsigned NumKilled = ISelKilled.size();\n";
   OS << "  }\n";
   OS << "}\n\n";
 
-  OS << "inline void ReplaceUses(SDOperand F, SDOperand T) {\n";
+  OS << "void ReplaceUses(SDOperand F, SDOperand T) NOINLINE {\n";
   OS << "  CurDAG->ReplaceAllUsesOfValueWith(F, T, ISelKilled);\n";
   OS << "  setSelected(F.Val->getNodeId());\n";
   OS << "  RemoveKilled();\n";
+  OS << "}\n";
+  OS << "inline void ReplaceUses(SDNode *F, SDNode *T) {\n";
+  OS << "  CurDAG->ReplaceAllUsesWith(F, T, &ISelKilled);\n";
+  OS << "  setSelected(F->getNodeId());\n";
+  OS << "  RemoveKilled();\n";
   OS << "}\n\n";
 
   OS << "// SelectRoot - Top level entry to DAG isel.\n";
@@ -3626,8 +3653,10 @@ OS << "  unsigned NumKilled = ISelKilled.size();\n";
   OS << "    SDNode *Node = ISelQueue.front();\n";
   OS << "    std::pop_heap(ISelQueue.begin(), ISelQueue.end(), isel_sort());\n";
   OS << "    ISelQueue.pop_back();\n";
-  OS << "    if (!isSelected(Node->getNodeId()))\n";
-  OS << "      Select(Tmp, SDOperand(Node, 0));\n";
+  OS << "    if (!isSelected(Node->getNodeId())) {\n";
+  OS << "      SDNode *ResNode = Select(Tmp, SDOperand(Node, 0));\n";
+  OS << "      if (ResNode) ReplaceUses(Node, ResNode);\n";
+  OS << "    }\n";
   OS << "  }\n";
   OS << "\n";
   OS << "  delete[] ISelQueued;\n";