X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=utils%2FTableGen%2FRecord.cpp;h=53f90146a75a239da9ff4535743bbe71cb3cd38b;hb=9e6d1d1f5034347d237941f1bf08fba5c1583cd3;hp=e2d9657c4d24c03130f1f28d8f1db88403f11d6e;hpb=7cee81703de8333d457ec9e560b0537b71df5a48;p=oota-llvm.git

diff --git a/utils/TableGen/Record.cpp b/utils/TableGen/Record.cpp
index e2d9657c4d2..53f90146a75 100644
--- a/utils/TableGen/Record.cpp
+++ b/utils/TableGen/Record.cpp
@@ -12,10 +12,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "Record.h"
-#include "llvm/Support/DataTypes.h"
-#include "llvm/Support/Streams.h"
+#include "llvm/System/DataTypes.h"
+#include "llvm/Support/Format.h"
 #include "llvm/ADT/StringExtras.h"
-#include <ios>
 
 using namespace llvm;
 
@@ -23,7 +22,7 @@ using namespace llvm;
 //    Type implementations
 //===----------------------------------------------------------------------===//
 
-void RecTy::dump() const { print(*cerr.stream()); }
+void RecTy::dump() const { print(errs()); }
 
 Init *BitRecTy::convertValue(BitsInit *BI) {
   if (BI->getNumBits() != 1) return 0; // Only accept if just one bit!
@@ -132,16 +131,39 @@ Init *IntRecTy::convertValue(TypedInit *TI) {
   return 0;
 }
 
+Init *StringRecTy::convertValue(UnOpInit *BO) {
+  if (BO->getOpcode() == UnOpInit::CAST) {
+    Init *L = BO->getOperand()->convertInitializerTo(this);
+    if (L == 0) return 0;
+    if (L != BO->getOperand())
+      return new UnOpInit(UnOpInit::CAST, L, new StringRecTy);
+    return BO;
+  }
+
+  return convertValue((TypedInit*)BO);
+}
+
 Init *StringRecTy::convertValue(BinOpInit *BO) {
   if (BO->getOpcode() == BinOpInit::STRCONCAT) {
     Init *L = BO->getLHS()->convertInitializerTo(this);
     Init *R = BO->getRHS()->convertInitializerTo(this);
     if (L == 0 || R == 0) return 0;
     if (L != BO->getLHS() || R != BO->getRHS())
-      return new BinOpInit(BinOpInit::STRCONCAT, L, R);
+      return new BinOpInit(BinOpInit::STRCONCAT, L, R, new StringRecTy);
     return BO;
   }
-  return 0;
+  if (BO->getOpcode() == BinOpInit::NAMECONCAT) {
+    if (BO->getType()->getAsString() == getAsString()) {
+      Init *L = BO->getLHS()->convertInitializerTo(this);
+      Init *R = BO->getRHS()->convertInitializerTo(this);
+      if (L == 0 || R == 0) return 0;
+      if (L != BO->getLHS() || R != BO->getRHS())
+        return new BinOpInit(BinOpInit::NAMECONCAT, L, R, new StringRecTy);
+      return BO;
+    }
+  }
+
+  return convertValue((TypedInit*)BO);
 }
 
 
@@ -166,7 +188,12 @@ Init *ListRecTy::convertValue(ListInit *LI) {
     else
       return 0;
 
-  return new ListInit(Elements);
+  ListRecTy *LType = dynamic_cast<ListRecTy*>(LI->getType());
+  if (LType == 0) {
+    return 0;
+  }
+
+  return new ListInit(Elements, new ListRecTy(Ty));
 }
 
 Init *ListRecTy::convertValue(TypedInit *TI) {
@@ -189,15 +216,36 @@ Init *DagRecTy::convertValue(TypedInit *TI) {
   return 0;
 }
 
+Init *DagRecTy::convertValue(UnOpInit *BO) {
+  if (BO->getOpcode() == UnOpInit::CAST) {
+    Init *L = BO->getOperand()->convertInitializerTo(this);
+    if (L == 0) return 0;
+    if (L != BO->getOperand())
+      return new UnOpInit(UnOpInit::CAST, L, new DagRecTy);
+    return BO;
+  }
+  return 0;
+}
+
 Init *DagRecTy::convertValue(BinOpInit *BO) {
   if (BO->getOpcode() == BinOpInit::CONCAT) {
     Init *L = BO->getLHS()->convertInitializerTo(this);
     Init *R = BO->getRHS()->convertInitializerTo(this);
     if (L == 0 || R == 0) return 0;
     if (L != BO->getLHS() || R != BO->getRHS())
-      return new BinOpInit(BinOpInit::CONCAT, L, R);
+      return new BinOpInit(BinOpInit::CONCAT, L, R, new DagRecTy);
     return BO;
   }
+  if (BO->getOpcode() == BinOpInit::NAMECONCAT) {
+    if (BO->getType()->getAsString() == getAsString()) {
+      Init *L = BO->getLHS()->convertInitializerTo(this);
+      Init *R = BO->getRHS()->convertInitializerTo(this);
+      if (L == 0 || R == 0) return 0;
+      if (L != BO->getLHS() || R != BO->getRHS())
+        return new BinOpInit(BinOpInit::CONCAT, L, R, new DagRecTy);
+      return BO;
+    }
+  }
   return 0;
 }
 
@@ -226,11 +274,64 @@ bool RecordRecTy::baseClassOf(const RecordRecTy *RHS) const {
 }
 
 
+/// resolveTypes - Find a common type that T1 and T2 convert to.
+/// Return 0 if no such type exists.
+///
+RecTy *llvm::resolveTypes(RecTy *T1, RecTy *T2) {
+  if (!T1->typeIsConvertibleTo(T2)) {
+    if (!T2->typeIsConvertibleTo(T1)) {
+      // If one is a Record type, check superclasses
+      RecordRecTy *RecTy1 = dynamic_cast<RecordRecTy*>(T1);
+      if (RecTy1) {
+        // See if T2 inherits from a type T1 also inherits from
+        const std::vector<Record *> &T1SuperClasses =
+          RecTy1->getRecord()->getSuperClasses();
+        for(std::vector<Record *>::const_iterator i = T1SuperClasses.begin(),
+              iend = T1SuperClasses.end();
+            i != iend;
+            ++i) {
+          RecordRecTy *SuperRecTy1 = new RecordRecTy(*i);
+          RecTy *NewType1 = resolveTypes(SuperRecTy1, T2);
+          if (NewType1 != 0) {
+            if (NewType1 != SuperRecTy1) {
+              delete SuperRecTy1;
+            }
+            return NewType1;
+          }
+        }
+      }
+      RecordRecTy *RecTy2 = dynamic_cast<RecordRecTy*>(T2);
+      if (RecTy2) {
+        // See if T1 inherits from a type T2 also inherits from
+        const std::vector<Record *> &T2SuperClasses =
+          RecTy2->getRecord()->getSuperClasses();
+        for (std::vector<Record *>::const_iterator i = T2SuperClasses.begin(),
+              iend = T2SuperClasses.end();
+            i != iend;
+            ++i) {
+          RecordRecTy *SuperRecTy2 = new RecordRecTy(*i);
+          RecTy *NewType2 = resolveTypes(T1, SuperRecTy2);
+          if (NewType2 != 0) {
+            if (NewType2 != SuperRecTy2) {
+              delete SuperRecTy2;
+            }
+            return NewType2;
+          }
+        }
+      }
+      return 0;
+    }
+    return T2;
+  }
+  return T1;
+}
+
+
 //===----------------------------------------------------------------------===//
 //    Initializer implementations
 //===----------------------------------------------------------------------===//
 
-void Init::dump() const { return print(*cerr.stream()); }
+void Init::dump() const { return print(errs()); }
 
 Init *BitsInit::convertInitializerBitRange(const std::vector<unsigned> &Bits) {
   BitsInit *BI = new BitsInit(Bits.size());
@@ -245,10 +346,6 @@ Init *BitsInit::convertInitializerBitRange(const std::vector<unsigned> &Bits) {
 }
 
 std::string BitsInit::getAsString() const {
-  //if (!printInHex(OS)) return;
-  //if (!printAsVariable(OS)) return;
-  //if (!printAsUnset(OS)) return;
-
   std::string Result = "{ ";
   for (unsigned i = 0, e = getNumBits(); i != e; ++i) {
     if (i) Result += ", ";
@@ -260,51 +357,6 @@ std::string BitsInit::getAsString() const {
   return Result + " }";
 }
 
-bool BitsInit::printInHex(std::ostream &OS) const {
-  // First, attempt to convert the value into an integer value...
-  int64_t Result = 0;
-  for (unsigned i = 0, e = getNumBits(); i != e; ++i)
-    if (BitInit *Bit = dynamic_cast<BitInit*>(getBit(i))) {
-      Result |= Bit->getValue() << i;
-    } else {
-      return true;
-    }
-
-  OS << "0x" << std::hex << Result << std::dec;
-  return false;
-}
-
-bool BitsInit::printAsVariable(std::ostream &OS) const {
-  // Get the variable that we may be set equal to...
-  assert(getNumBits() != 0);
-  VarBitInit *FirstBit = dynamic_cast<VarBitInit*>(getBit(0));
-  if (FirstBit == 0) return true;
-  TypedInit *Var = FirstBit->getVariable();
-
-  // Check to make sure the types are compatible.
-  BitsRecTy *Ty = dynamic_cast<BitsRecTy*>(FirstBit->getVariable()->getType());
-  if (Ty == 0) return true;
-  if (Ty->getNumBits() != getNumBits()) return true; // Incompatible types!
-
-  // Check to make sure all bits are referring to the right bits in the variable
-  for (unsigned i = 0, e = getNumBits(); i != e; ++i) {
-    VarBitInit *Bit = dynamic_cast<VarBitInit*>(getBit(i));
-    if (Bit == 0 || Bit->getVariable() != Var || Bit->getBitNum() != i)
-      return true;
-  }
-
-  Var->print(OS);
-  return false;
-}
-
-bool BitsInit::printAsUnset(std::ostream &OS) const {
-  for (unsigned i = 0, e = getNumBits(); i != e; ++i)
-    if (!dynamic_cast<UnsetInit*>(getBit(i)))
-      return true;
-  OS << "?";
-  return false;
-}
-
 // resolveReferences - If there are any field references that refer to fields
 // that have been filled in, we can propagate the values now.
 //
@@ -354,7 +406,7 @@ Init *ListInit::convertInitListSlice(const std::vector<unsigned> &Elements) {
       return 0;
     Vals.push_back(getElement(Elements[i]));
   }
-  return new ListInit(Vals);
+  return new ListInit(Vals, getType());
 }
 
 Record *ListInit::getElementAsRecord(unsigned i) const {
@@ -382,10 +434,23 @@ Init *ListInit::resolveReferences(Record &R, const RecordVal *RV) {
   }
 
   if (Changed)
-    return new ListInit(Resolved);
+    return new ListInit(Resolved, getType());
   return this;
 }
 
+Init *ListInit::resolveListElementReference(Record &R, const RecordVal *IRV,
+                                            unsigned Elt) {
+  if (Elt >= getSize())
+    return 0;  // Out of range reference.
+  Init *E = getElement(Elt);
+  // If the element is set to some value, or if we are resolving a reference
+  // to a specific variable and that variable is explicitly unset, then
+  // replace the VarListElementInit with it.
+  if (IRV || !dynamic_cast<UnsetInit*>(E))
+    return E;
+  return 0;
+}
+
 std::string ListInit::getAsString() const {
   std::string Result = "[";
   for (unsigned i = 0, e = Values.size(); i != e; ++i) {
@@ -395,7 +460,184 @@ std::string ListInit::getAsString() const {
   return Result + "]";
 }
 
-Init *BinOpInit::Fold() {
+Init *OpInit::resolveBitReference(Record &R, const RecordVal *IRV,
+                                  unsigned Bit) {
+  Init *Folded = Fold(&R, 0);
+
+  if (Folded != this) {
+    TypedInit *Typed = dynamic_cast<TypedInit *>(Folded);
+    if (Typed) {
+      return Typed->resolveBitReference(R, IRV, Bit);
+    }
+  }
+
+  return 0;
+}
+
+Init *OpInit::resolveListElementReference(Record &R, const RecordVal *IRV,
+                                          unsigned Elt) {
+  Init *Folded = Fold(&R, 0);
+
+  if (Folded != this) {
+    TypedInit *Typed = dynamic_cast<TypedInit *>(Folded);
+    if (Typed) {
+      return Typed->resolveListElementReference(R, IRV, Elt);
+    }
+  }
+
+  return 0;
+}
+
+Init *UnOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) {
+  switch (getOpcode()) {
+  default: assert(0 && "Unknown unop");
+  case CAST: {
+    if (getType()->getAsString() == "string") {
+      StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
+      if (LHSs) {
+        return LHSs;
+      }
+
+      DefInit *LHSd = dynamic_cast<DefInit*>(LHS);
+      if (LHSd) {
+        return new StringInit(LHSd->getDef()->getName());
+      }
+    } else {
+      StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
+      if (LHSs) {
+        std::string Name = LHSs->getValue();
+
+        // From TGParser::ParseIDValue
+        if (CurRec) {
+          if (const RecordVal *RV = CurRec->getValue(Name)) {
+            if (RV->getType() != getType()) {
+              throw "type mismatch in nameconcat";
+            }
+            return new VarInit(Name, RV->getType());
+          }
+
+          std::string TemplateArgName = CurRec->getName()+":"+Name;
+          if (CurRec->isTemplateArg(TemplateArgName)) {
+            const RecordVal *RV = CurRec->getValue(TemplateArgName);
+            assert(RV && "Template arg doesn't exist??");
+
+            if (RV->getType() != getType()) {
+              throw "type mismatch in nameconcat";
+            }
+
+            return new VarInit(TemplateArgName, RV->getType());
+          }
+        }
+
+        if (CurMultiClass) {
+          std::string MCName = CurMultiClass->Rec.getName()+"::"+Name;
+          if (CurMultiClass->Rec.isTemplateArg(MCName)) {
+            const RecordVal *RV = CurMultiClass->Rec.getValue(MCName);
+            assert(RV && "Template arg doesn't exist??");
+
+            if (RV->getType() != getType()) {
+              throw "type mismatch in nameconcat";
+            }
+
+            return new VarInit(MCName, RV->getType());
+          }
+        }
+
+        if (Record *D = Records.getDef(Name))
+          return new DefInit(D);
+
+        errs() << "Variable not defined: '" + Name + "'\n";
+        assert(0 && "Variable not found");
+        return 0;
+      }
+    }
+    break;
+  }
+  case CAR: {
+    ListInit *LHSl = dynamic_cast<ListInit*>(LHS);
+    if (LHSl) {
+      if (LHSl->getSize() == 0) {
+        assert(0 && "Empty list in car");
+        return 0;
+      }
+      return LHSl->getElement(0);
+    }
+    break;
+  }
+  case CDR: {
+    ListInit *LHSl = dynamic_cast<ListInit*>(LHS);
+    if (LHSl) {
+      if (LHSl->getSize() == 0) {
+        assert(0 && "Empty list in cdr");
+        return 0;
+      }
+      ListInit *Result = new ListInit(LHSl->begin()+1, LHSl->end(),
+                                      LHSl->getType());
+      return Result;
+    }
+    break;
+  }
+  case LNULL: {
+    ListInit *LHSl = dynamic_cast<ListInit*>(LHS);
+    if (LHSl) {
+      if (LHSl->getSize() == 0) {
+        return new IntInit(1);
+      } else {
+        return new IntInit(0);
+      }
+    }
+    StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
+    if (LHSs) {
+      if (LHSs->getValue().empty()) {
+        return new IntInit(1);
+      } else {
+        return new IntInit(0);
+      }
+    }
+
+    break;
+  }
+  }
+  return this;
+}
+
+Init *UnOpInit::resolveReferences(Record &R, const RecordVal *RV) {
+  Init *lhs = LHS->resolveReferences(R, RV);
+
+  if (LHS != lhs)
+    return (new UnOpInit(getOpcode(), lhs, getType()))->Fold(&R, 0);
+  return Fold(&R, 0);
+}
+
+std::string UnOpInit::getAsString() const {
+  std::string Result;
+  switch (Opc) {
+  case CAST: Result = "!cast<" + getType()->getAsString() + ">"; break;
+  case CAR: Result = "!car"; break;
+  case CDR: Result = "!cdr"; break;
+  case LNULL: Result = "!null"; break;
+  }
+  return Result + "(" + LHS->getAsString() + ")";
+}
+
+RecTy *UnOpInit::getFieldType(const std::string &FieldName) const {
+  switch (getOpcode()) {
+  default: assert(0 && "Unknown unop");
+  case CAST: {
+    RecordRecTy *RecordType = dynamic_cast<RecordRecTy *>(getType());
+    if (RecordType) {
+      RecordVal *Field = RecordType->getRecord()->getValue(FieldName);
+      if (Field) {
+        return Field->getType();
+      }
+    }
+    break;
+  }
+  }
+  return 0;
+}
+
+Init *BinOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) {
   switch (getOpcode()) {
   default: assert(0 && "Unknown binop");
   case CONCAT: {
@@ -437,6 +679,57 @@ Init *BinOpInit::Fold() {
       return new StringInit(LHSs->getValue() + RHSs->getValue());
     break;
   }
+  case NAMECONCAT: {
+    StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
+    StringInit *RHSs = dynamic_cast<StringInit*>(RHS);
+    if (LHSs && RHSs) {
+      std::string Name(LHSs->getValue() + RHSs->getValue());
+
+      // From TGParser::ParseIDValue
+      if (CurRec) {
+        if (const RecordVal *RV = CurRec->getValue(Name)) {
+          if (RV->getType() != getType()) {
+            throw "type mismatch in nameconcat";
+          }
+          return new VarInit(Name, RV->getType());
+        }
+
+        std::string TemplateArgName = CurRec->getName()+":"+Name;
+        if (CurRec->isTemplateArg(TemplateArgName)) {
+          const RecordVal *RV = CurRec->getValue(TemplateArgName);
+          assert(RV && "Template arg doesn't exist??");
+
+          if (RV->getType() != getType()) {
+            throw "type mismatch in nameconcat";
+          }
+
+          return new VarInit(TemplateArgName, RV->getType());
+        }
+      }
+
+      if (CurMultiClass) {
+        std::string MCName = CurMultiClass->Rec.getName()+"::"+Name;
+        if (CurMultiClass->Rec.isTemplateArg(MCName)) {
+          const RecordVal *RV = CurMultiClass->Rec.getValue(MCName);
+          assert(RV && "Template arg doesn't exist??");
+
+          if (RV->getType() != getType()) {
+            throw "type mismatch in nameconcat";
+          }
+
+          return new VarInit(MCName, RV->getType());
+        }
+      }
+
+      if (Record *D = Records.getDef(Name))
+        return new DefInit(D);
+
+      errs() << "Variable not defined in !nameconcat: '" + Name + "'\n";
+      assert(0 && "Variable not found in !nameconcat");
+      return 0;
+    }
+    break;
+  }
   case SHL:
   case SRA:
   case SRL: {
@@ -462,10 +755,10 @@ Init *BinOpInit::Fold() {
 Init *BinOpInit::resolveReferences(Record &R, const RecordVal *RV) {
   Init *lhs = LHS->resolveReferences(R, RV);
   Init *rhs = RHS->resolveReferences(R, RV);
-  
+
   if (LHS != lhs || RHS != rhs)
-    return (new BinOpInit(getOpcode(), lhs, rhs))->Fold();
-  return Fold();
+    return (new BinOpInit(getOpcode(), lhs, rhs, getType()))->Fold(&R, 0);
+  return Fold(&R, 0);
 }
 
 std::string BinOpInit::getAsString() const {
@@ -476,10 +769,258 @@ std::string BinOpInit::getAsString() const {
   case SRA: Result = "!sra"; break;
   case SRL: Result = "!srl"; break;
   case STRCONCAT: Result = "!strconcat"; break;
+  case NAMECONCAT:
+    Result = "!nameconcat<" + getType()->getAsString() + ">"; break;
   }
   return Result + "(" + LHS->getAsString() + ", " + RHS->getAsString() + ")";
 }
 
+static Init *ForeachHelper(Init *LHS, Init *MHS, Init *RHS, RecTy *Type,
+                           Record *CurRec, MultiClass *CurMultiClass);
+
+static Init *EvaluateOperation(OpInit *RHSo, Init *LHS, Init *Arg,
+                               RecTy *Type, Record *CurRec,
+                               MultiClass *CurMultiClass) {
+  std::vector<Init *> NewOperands;
+
+  TypedInit *TArg = dynamic_cast<TypedInit*>(Arg);
+
+  // If this is a dag, recurse
+  if (TArg && TArg->getType()->getAsString() == "dag") {
+    Init *Result = ForeachHelper(LHS, Arg, RHSo, Type,
+                                 CurRec, CurMultiClass);
+    if (Result != 0) {
+      return Result;
+    } else {
+      return 0;
+    }
+  }
+
+  for (int i = 0; i < RHSo->getNumOperands(); ++i) {
+    OpInit *RHSoo = dynamic_cast<OpInit*>(RHSo->getOperand(i));
+
+    if (RHSoo) {
+      Init *Result = EvaluateOperation(RHSoo, LHS, Arg,
+                                       Type, CurRec, CurMultiClass);
+      if (Result != 0) {
+        NewOperands.push_back(Result);
+      } else {
+        NewOperands.push_back(Arg);
+      }
+    } else if (LHS->getAsString() == RHSo->getOperand(i)->getAsString()) {
+      NewOperands.push_back(Arg);
+    } else {
+      NewOperands.push_back(RHSo->getOperand(i));
+    }
+  }
+
+  // Now run the operator and use its result as the new leaf
+  OpInit *NewOp = RHSo->clone(NewOperands);
+  Init *NewVal = NewOp->Fold(CurRec, CurMultiClass);
+  if (NewVal != NewOp) {
+    delete NewOp;
+    return NewVal;
+  }
+  return 0;
+}
+
+static Init *ForeachHelper(Init *LHS, Init *MHS, Init *RHS, RecTy *Type,
+                           Record *CurRec, MultiClass *CurMultiClass) {
+  DagInit *MHSd = dynamic_cast<DagInit*>(MHS);
+  ListInit *MHSl = dynamic_cast<ListInit*>(MHS);
+
+  DagRecTy *DagType = dynamic_cast<DagRecTy*>(Type);
+  ListRecTy *ListType = dynamic_cast<ListRecTy*>(Type);
+
+  OpInit *RHSo = dynamic_cast<OpInit*>(RHS);
+
+  if (!RHSo) {
+    errs() << "!foreach requires an operator\n";
+    assert(0 && "No operator for !foreach");
+  }
+
+  TypedInit *LHSt = dynamic_cast<TypedInit*>(LHS);
+
+  if (!LHSt) {
+    errs() << "!foreach requires typed variable\n";
+    assert(0 && "No typed variable for !foreach");
+  }
+
+  if ((MHSd && DagType) || (MHSl && ListType)) {
+    if (MHSd) {
+      Init *Val = MHSd->getOperator();
+      Init *Result = EvaluateOperation(RHSo, LHS, Val,
+                                       Type, CurRec, CurMultiClass);
+      if (Result != 0) {
+        Val = Result;
+      }
+
+      std::vector<std::pair<Init *, std::string> > args;
+      for (unsigned int i = 0; i < MHSd->getNumArgs(); ++i) {
+        Init *Arg;
+        std::string ArgName;
+        Arg = MHSd->getArg(i);
+        ArgName = MHSd->getArgName(i);
+
+        // Process args
+        Init *Result = EvaluateOperation(RHSo, LHS, Arg, Type,
+                                         CurRec, CurMultiClass);
+        if (Result != 0) {
+          Arg = Result;
+        }
+
+        // TODO: Process arg names
+        args.push_back(std::make_pair(Arg, ArgName));
+      }
+
+      return new DagInit(Val, "", args);
+    }
+    if (MHSl) {
+      std::vector<Init *> NewOperands;
+      std::vector<Init *> NewList(MHSl->begin(), MHSl->end());
+
+      for (ListInit::iterator li = NewList.begin(),
+             liend = NewList.end();
+           li != liend;
+           ++li) {
+        Init *Item = *li;
+        NewOperands.clear();
+        for(int i = 0; i < RHSo->getNumOperands(); ++i) {
+          // First, replace the foreach variable with the list item
+          if (LHS->getAsString() == RHSo->getOperand(i)->getAsString()) {
+            NewOperands.push_back(Item);
+          } else {
+            NewOperands.push_back(RHSo->getOperand(i));
+          }
+        }
+
+        // Now run the operator and use its result as the new list item
+        OpInit *NewOp = RHSo->clone(NewOperands);
+        Init *NewItem = NewOp->Fold(CurRec, CurMultiClass);
+        if (NewItem != NewOp) {
+          *li = NewItem;
+          delete NewOp;
+        }
+      }
+      return new ListInit(NewList, MHSl->getType());
+    }
+  }
+  return 0;
+}
+
+Init *TernOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) {
+  switch (getOpcode()) {
+  default: assert(0 && "Unknown binop");
+  case SUBST: {
+    DefInit *LHSd = dynamic_cast<DefInit*>(LHS);
+    VarInit *LHSv = dynamic_cast<VarInit*>(LHS);
+    StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
+
+    DefInit *MHSd = dynamic_cast<DefInit*>(MHS);
+    VarInit *MHSv = dynamic_cast<VarInit*>(MHS);
+    StringInit *MHSs = dynamic_cast<StringInit*>(MHS);
+
+    DefInit *RHSd = dynamic_cast<DefInit*>(RHS);
+    VarInit *RHSv = dynamic_cast<VarInit*>(RHS);
+    StringInit *RHSs = dynamic_cast<StringInit*>(RHS);
+
+    if ((LHSd && MHSd && RHSd)
+        || (LHSv && MHSv && RHSv)
+        || (LHSs && MHSs && RHSs)) {
+      if (RHSd) {
+        Record *Val = RHSd->getDef();
+        if (LHSd->getAsString() == RHSd->getAsString()) {
+          Val = MHSd->getDef();
+        }
+        return new DefInit(Val);
+      }
+      if (RHSv) {
+        std::string Val = RHSv->getName();
+        if (LHSv->getAsString() == RHSv->getAsString()) {
+          Val = MHSv->getName();
+        }
+        return new VarInit(Val, getType());
+      }
+      if (RHSs) {
+        std::string Val = RHSs->getValue();
+
+        std::string::size_type found;
+        do {
+          found = Val.find(LHSs->getValue());
+          if (found != std::string::npos) {
+            Val.replace(found, LHSs->getValue().size(), MHSs->getValue());
+          }
+        } while (found != std::string::npos);
+
+        return new StringInit(Val);
+      }
+    }
+    break;
+  }
+
+  case FOREACH: {
+    Init *Result = ForeachHelper(LHS, MHS, RHS, getType(),
+                                 CurRec, CurMultiClass);
+    if (Result != 0) {
+      return Result;
+    }
+    break;
+  }
+
+  case IF: {
+    IntInit *LHSi = dynamic_cast<IntInit*>(LHS);
+    if (LHSi) {
+      if (LHSi->getValue()) {
+        return MHS;
+      } else {
+        return RHS;
+      }
+    }
+    break;
+  }
+  }
+
+  return this;
+}
+
+Init *TernOpInit::resolveReferences(Record &R, const RecordVal *RV) {
+  Init *lhs = LHS->resolveReferences(R, RV);
+
+  if (Opc == IF && lhs != LHS) {
+    IntInit *Value = dynamic_cast<IntInit*>(lhs);
+    if (Value != 0) {
+      // Short-circuit
+      if (Value->getValue()) {
+        Init *mhs = MHS->resolveReferences(R, RV);
+        return (new TernOpInit(getOpcode(), lhs, mhs,
+                               RHS, getType()))->Fold(&R, 0);
+      } else {
+        Init *rhs = RHS->resolveReferences(R, RV);
+        return (new TernOpInit(getOpcode(), lhs, MHS,
+                               rhs, getType()))->Fold(&R, 0);
+      }
+    }
+  }
+
+  Init *mhs = MHS->resolveReferences(R, RV);
+  Init *rhs = RHS->resolveReferences(R, RV);
+
+  if (LHS != lhs || MHS != mhs || RHS != rhs)
+    return (new TernOpInit(getOpcode(), lhs, mhs, rhs, getType()))->Fold(&R, 0);
+  return Fold(&R, 0);
+}
+
+std::string TernOpInit::getAsString() const {
+  std::string Result;
+  switch (Opc) {
+  case SUBST: Result = "!subst"; break;
+  case FOREACH: Result = "!foreach"; break;
+  case IF: Result = "!if"; break;
+ }
+  return Result + "(" + LHS->getAsString() + ", " + MHS->getAsString() + ", "
+    + RHS->getAsString() + ")";
+}
+
 Init *TypedInit::convertInitializerBitRange(const std::vector<unsigned> &Bits) {
   BitsRecTy *T = dynamic_cast<BitsRecTy*>(getType());
   if (T == 0) return 0;  // Cannot subscript a non-bits variable...
@@ -507,7 +1048,7 @@ Init *TypedInit::convertInitListSlice(const std::vector<unsigned> &Elements) {
   ListInits.reserve(Elements.size());
   for (unsigned i = 0, e = Elements.size(); i != e; ++i)
     ListInits.push_back(new VarListElementInit(this, Elements[i]));
-  return new ListInit(ListInits);
+  return new ListInit(ListInits, T);
 }
 
 
@@ -517,15 +1058,18 @@ Init *VarInit::resolveBitReference(Record &R, const RecordVal *IRV,
   if (IRV && IRV->getName() != getName()) return 0;
 
   RecordVal *RV = R.getValue(getName());
-  assert(RV && "Reference to a non-existant variable?");
+  assert(RV && "Reference to a non-existent variable?");
   assert(dynamic_cast<BitsInit*>(RV->getValue()));
   BitsInit *BI = (BitsInit*)RV->getValue();
 
   assert(Bit < BI->getNumBits() && "Bit reference out of range!");
   Init *B = BI->getBit(Bit);
 
-  if (!dynamic_cast<UnsetInit*>(B))  // If the bit is not set...
-    return B;                        // Replace the VarBitInit with it.
+  // If the bit is set to some value, or if we are resolving a reference to a
+  // specific variable and that variable is explicitly unset, then replace the
+  // VarBitInit with it.
+  if (IRV || !dynamic_cast<UnsetInit*>(B))
+    return B;
   return 0;
 }
 
@@ -535,15 +1079,22 @@ Init *VarInit::resolveListElementReference(Record &R, const RecordVal *IRV,
   if (IRV && IRV->getName() != getName()) return 0;
 
   RecordVal *RV = R.getValue(getName());
-  assert(RV && "Reference to a non-existant variable?");
+  assert(RV && "Reference to a non-existent variable?");
   ListInit *LI = dynamic_cast<ListInit*>(RV->getValue());
-  assert(LI && "Invalid list element!");
+  if (!LI) {
+    VarInit *VI = dynamic_cast<VarInit*>(RV->getValue());
+    assert(VI && "Invalid list element!");
+    return new VarListElementInit(VI, Elt);
+  }
 
   if (Elt >= LI->getSize())
     return 0;  // Out of range reference.
   Init *E = LI->getElement(Elt);
-  if (!dynamic_cast<UnsetInit*>(E))  // If the element is set
-    return E;                        // Replace the VarListElementInit with it.
+  // If the element is set to some value, or if we are resolving a reference
+  // to a specific variable and that variable is explicitly unset, then
+  // replace the VarListElementInit with it.
+  if (IRV || !dynamic_cast<UnsetInit*>(E))
+    return E;
   return 0;
 }
 
@@ -569,7 +1120,7 @@ Init *VarInit::getFieldInit(Record &R, const std::string &FieldName) const {
 }
 
 /// resolveReferences - This method is used by classes that refer to other
-/// variables which may not be defined at the time they expression is formed.
+/// variables which may not be defined at the time the expression is formed.
 /// If a value is set for the variable later, this method will be called on
 /// users of the value to allow the value to propagate out.
 ///
@@ -650,8 +1201,11 @@ Init *FieldInit::resolveListElementReference(Record &R, const RecordVal *RV,
       if (Elt >= LI->getSize()) return 0;
       Init *E = LI->getElement(Elt);
 
-      if (!dynamic_cast<UnsetInit*>(E))  // If the bit is set...
-        return E;                  // Replace the VarListElementInit with it.
+      // If the element is set to some value, or if we are resolving a
+      // reference to a specific variable and that variable is explicitly
+      // unset, then replace the VarListElementInit with it.
+      if (RV || !dynamic_cast<UnsetInit*>(E))
+        return E;
     }
   return 0;
 }
@@ -675,12 +1229,12 @@ Init *DagInit::resolveReferences(Record &R, const RecordVal *RV) {
   std::vector<Init*> NewArgs;
   for (unsigned i = 0, e = Args.size(); i != e; ++i)
     NewArgs.push_back(Args[i]->resolveReferences(R, RV));
-  
+
   Init *Op = Val->resolveReferences(R, RV);
-  
+
   if (Args != NewArgs || Op != Val)
     return new DagInit(Op, "", NewArgs, ArgNames);
-    
+
   return this;
 }
 
@@ -711,9 +1265,9 @@ RecordVal::RecordVal(const std::string &N, RecTy *T, unsigned P)
   assert(Value && "Cannot create unset value for current type!");
 }
 
-void RecordVal::dump() const { cerr << *this; }
+void RecordVal::dump() const { errs() << *this; }
 
-void RecordVal::print(std::ostream &OS, bool PrintSem) const {
+void RecordVal::print(raw_ostream &OS, bool PrintSem) const {
   if (getPrefix()) OS << "field ";
   OS << *getType() << " " << getName();
 
@@ -723,6 +1277,8 @@ void RecordVal::print(std::ostream &OS, bool PrintSem) const {
   if (PrintSem) OS << ";\n";
 }
 
+unsigned Record::LastID = 0;
+
 void Record::setName(const std::string &Name) {
   if (Records.getDef(getName()) == this) {
     Records.removeDef(getName());
@@ -746,9 +1302,9 @@ void Record::resolveReferencesTo(const RecordVal *RV) {
 }
 
 
-void Record::dump() const { cerr << *this; }
+void Record::dump() const { errs() << *this; }
 
-std::ostream &llvm::operator<<(std::ostream &OS, const Record &R) {
+raw_ostream &llvm::operator<<(raw_ostream &OS, const Record &R) {
   OS << R.getName();
 
   const std::vector<std::string> &TArgs = R.getTemplateArgs();
@@ -786,11 +1342,11 @@ std::ostream &llvm::operator<<(std::ostream &OS, const Record &R) {
 /// getValueInit - Return the initializer for a value with the specified name,
 /// or throw an exception if the field does not exist.
 ///
-Init *Record::getValueInit(const std::string &FieldName) const {
+Init *Record::getValueInit(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-      FieldName + "'!\n";
+      FieldName.str() + "'!\n";
   return R->getValue();
 }
 
@@ -799,15 +1355,15 @@ Init *Record::getValueInit(const std::string &FieldName) const {
 /// value as a string, throwing an exception if the field does not exist or if
 /// the value is not a string.
 ///
-std::string Record::getValueAsString(const std::string &FieldName) const {
+std::string Record::getValueAsString(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-          FieldName + "'!\n";
+          FieldName.str() + "'!\n";
 
   if (const StringInit *SI = dynamic_cast<const StringInit*>(R->getValue()))
     return SI->getValue();
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a string initializer!";
 }
 
@@ -815,15 +1371,15 @@ std::string Record::getValueAsString(const std::string &FieldName) const {
 /// its value as a BitsInit, throwing an exception if the field does not exist
 /// or if the value is not the right type.
 ///
-BitsInit *Record::getValueAsBitsInit(const std::string &FieldName) const {
+BitsInit *Record::getValueAsBitsInit(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-          FieldName + "'!\n";
+          FieldName.str() + "'!\n";
 
   if (BitsInit *BI = dynamic_cast<BitsInit*>(R->getValue()))
     return BI;
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a BitsInit initializer!";
 }
 
@@ -831,15 +1387,15 @@ BitsInit *Record::getValueAsBitsInit(const std::string &FieldName) const {
 /// its value as a ListInit, throwing an exception if the field does not exist
 /// or if the value is not the right type.
 ///
-ListInit *Record::getValueAsListInit(const std::string &FieldName) const {
+ListInit *Record::getValueAsListInit(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-          FieldName + "'!\n";
+          FieldName.str() + "'!\n";
 
   if (ListInit *LI = dynamic_cast<ListInit*>(R->getValue()))
     return LI;
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a list initializer!";
 }
 
@@ -847,15 +1403,15 @@ ListInit *Record::getValueAsListInit(const std::string &FieldName) const {
 /// its value as a vector of records, throwing an exception if the field does
 /// not exist or if the value is not the right type.
 ///
-std::vector<Record*> 
-Record::getValueAsListOfDefs(const std::string &FieldName) const {
+std::vector<Record*>
+Record::getValueAsListOfDefs(StringRef FieldName) const {
   ListInit *List = getValueAsListInit(FieldName);
   std::vector<Record*> Defs;
   for (unsigned i = 0; i < List->getSize(); i++) {
     if (DefInit *DI = dynamic_cast<DefInit*>(List->getElement(i))) {
       Defs.push_back(DI->getDef());
     } else {
-      throw "Record `" + getName() + "', field `" + FieldName +
+      throw "Record `" + getName() + "', field `" + FieldName.str() +
             "' list is not entirely DefInit!";
     }
   }
@@ -866,15 +1422,15 @@ Record::getValueAsListOfDefs(const std::string &FieldName) const {
 /// value as an int64_t, throwing an exception if the field does not exist or if
 /// the value is not the right type.
 ///
-int64_t Record::getValueAsInt(const std::string &FieldName) const {
+int64_t Record::getValueAsInt(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-          FieldName + "'!\n";
+          FieldName.str() + "'!\n";
 
   if (IntInit *II = dynamic_cast<IntInit*>(R->getValue()))
     return II->getValue();
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have an int initializer!";
 }
 
@@ -882,15 +1438,15 @@ int64_t Record::getValueAsInt(const std::string &FieldName) const {
 /// its value as a vector of integers, throwing an exception if the field does
 /// not exist or if the value is not the right type.
 ///
-std::vector<int64_t> 
-Record::getValueAsListOfInts(const std::string &FieldName) const {
+std::vector<int64_t>
+Record::getValueAsListOfInts(StringRef FieldName) const {
   ListInit *List = getValueAsListInit(FieldName);
   std::vector<int64_t> Ints;
   for (unsigned i = 0; i < List->getSize(); i++) {
     if (IntInit *II = dynamic_cast<IntInit*>(List->getElement(i))) {
       Ints.push_back(II->getValue());
     } else {
-      throw "Record `" + getName() + "', field `" + FieldName +
+      throw "Record `" + getName() + "', field `" + FieldName.str() +
             "' does not have a list of ints initializer!";
     }
   }
@@ -901,15 +1457,15 @@ Record::getValueAsListOfInts(const std::string &FieldName) const {
 /// value as a Record, throwing an exception if the field does not exist or if
 /// the value is not the right type.
 ///
-Record *Record::getValueAsDef(const std::string &FieldName) const {
+Record *Record::getValueAsDef(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-      FieldName + "'!\n";
+      FieldName.str() + "'!\n";
 
   if (DefInit *DI = dynamic_cast<DefInit*>(R->getValue()))
     return DI->getDef();
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a def initializer!";
 }
 
@@ -917,15 +1473,15 @@ Record *Record::getValueAsDef(const std::string &FieldName) const {
 /// value as a bit, throwing an exception if the field does not exist or if
 /// the value is not the right type.
 ///
-bool Record::getValueAsBit(const std::string &FieldName) const {
+bool Record::getValueAsBit(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-      FieldName + "'!\n";
+      FieldName.str() + "'!\n";
 
   if (BitInit *BI = dynamic_cast<BitInit*>(R->getValue()))
     return BI->getValue();
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a bit initializer!";
 }
 
@@ -933,34 +1489,48 @@ bool Record::getValueAsBit(const std::string &FieldName) const {
 /// value as an Dag, throwing an exception if the field does not exist or if
 /// the value is not the right type.
 ///
-DagInit *Record::getValueAsDag(const std::string &FieldName) const {
+DagInit *Record::getValueAsDag(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-      FieldName + "'!\n";
+      FieldName.str() + "'!\n";
 
   if (DagInit *DI = dynamic_cast<DagInit*>(R->getValue()))
     return DI;
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
         "' does not have a dag initializer!";
 }
 
-std::string Record::getValueAsCode(const std::string &FieldName) const {
+std::string Record::getValueAsCode(StringRef FieldName) const {
   const RecordVal *R = getValue(FieldName);
   if (R == 0 || R->getValue() == 0)
     throw "Record `" + getName() + "' does not have a field named `" +
-      FieldName + "'!\n";
-  
+      FieldName.str() + "'!\n";
+
   if (const CodeInit *CI = dynamic_cast<const CodeInit*>(R->getValue()))
     return CI->getValue();
-  throw "Record `" + getName() + "', field `" + FieldName +
+  throw "Record `" + getName() + "', field `" + FieldName.str() +
     "' does not have a code initializer!";
 }
 
 
-void RecordKeeper::dump() const { cerr << *this; }
+void MultiClass::dump() const {
+  errs() << "Record:\n";
+  Rec.dump();
+
+  errs() << "Defs:\n";
+  for (RecordVector::const_iterator r = DefPrototypes.begin(),
+         rend = DefPrototypes.end();
+       r != rend;
+       ++r) {
+    (*r)->dump();
+  }
+}
+
+
+void RecordKeeper::dump() const { errs() << *this; }
 
-std::ostream &llvm::operator<<(std::ostream &OS, const RecordKeeper &RK) {
+raw_ostream &llvm::operator<<(raw_ostream &OS, const RecordKeeper &RK) {
   OS << "------------- Classes -----------------\n";
   const std::map<std::string, Record*> &Classes = RK.getClasses();
   for (std::map<std::string, Record*>::const_iterator I = Classes.begin(),