Inline asm multiple alternative constraints development phase 2 - improved basic logic, added initial platform support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117667 91177308-0d34-0410-b5e6-96231b3b80d8

17 files changed, 393 insertions, 24 deletions

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 8509387447..39f8f05423 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -5441,6 +5441,40 @@ ARMTargetLowering::getConstraintType(const std::string &Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+ARMTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  const Type *type = CallOperandVal->getType();
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;
+  case 'l':
+    if (type->isIntegerTy()) {
+      if (Subtarget->isThumb())
+        weight = CW_SpecificReg;
+      else
+        weight = CW_Register;
+    }
+    break;
+  case 'w':
+    if (type->isFloatingPointTy())
+      weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 std::pair<unsigned, const TargetRegisterClass*>
 ARMTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
                                                 EVT VT) const {
diff --git a/lib/Target/ARM/ARMISelLowering.h b/lib/Target/ARM/ARMISelLowering.h
index a689f809f7..bf3553becc 100644
--- a/lib/Target/ARM/ARMISelLowering.h
+++ b/lib/Target/ARM/ARMISelLowering.h
@@ -241,6 +241,12 @@ namespace llvm {
 
 
     ConstraintType getConstraintType(const std::string &Constraint) const;
+
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*>
       getRegForInlineAsmConstraint(const std::string &Constraint,
                                    EVT VT) const;
diff --git a/lib/Target/Alpha/AlphaISelLowering.cpp b/lib/Target/Alpha/AlphaISelLowering.cpp
index efd0d2c4a9..9ae06eab75 100644
--- a/lib/Target/Alpha/AlphaISelLowering.cpp
+++ b/lib/Target/Alpha/AlphaISelLowering.cpp
@@ -27,6 +27,7 @@
 #include "llvm/Function.h"
 #include "llvm/Module.h"
 #include "llvm/Intrinsics.h"
+#include "llvm/Type.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
@@ -803,6 +804,30 @@ AlphaTargetLowering::getConstraintType(const std::string &Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+AlphaTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;
+  case 'f':
+    weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 std::vector<unsigned> AlphaTargetLowering::
 getRegClassForInlineAsmConstraint(const std::string &Constraint,
                                   EVT VT) const {
diff --git a/lib/Target/Alpha/AlphaISelLowering.h b/lib/Target/Alpha/AlphaISelLowering.h
index 46e0c7dc9f..b429e9fc13 100644
--- a/lib/Target/Alpha/AlphaISelLowering.h
+++ b/lib/Target/Alpha/AlphaISelLowering.h
@@ -87,6 +87,11 @@ namespace llvm {
 
     ConstraintType getConstraintType(const std::string &Constraint) const;
 
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::vector<unsigned> 
       getRegClassForInlineAsmConstraint(const std::string &Constraint,
                                         EVT VT) const;
diff --git a/lib/Target/Blackfin/BlackfinISelLowering.cpp b/lib/Target/Blackfin/BlackfinISelLowering.cpp
index 96d54aa03e..c07f1f2278 100644
--- a/lib/Target/Blackfin/BlackfinISelLowering.cpp
+++ b/lib/Target/Blackfin/BlackfinISelLowering.cpp
@@ -15,6 +15,7 @@
 #include "BlackfinISelLowering.h"
 #include "BlackfinTargetMachine.h"
 #include "llvm/Function.h"
+#include "llvm/Type.h"
 #include "llvm/CodeGen/CallingConvLower.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
@@ -549,6 +550,52 @@ BlackfinTargetLowering::getConstraintType(const std::string &Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+BlackfinTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;
+
+    // Blackfin-specific constraints
+  case 'a':
+  case 'd':
+  case 'z':
+  case 'D':
+  case 'W':
+  case 'e':
+  case 'b':
+  case 'v':
+  case 'f':
+  case 'c':
+  case 't':
+  case 'u':
+  case 'k':
+  case 'x':
+  case 'y':
+  case 'w':
+    return CW_Register;
+  case 'A':
+  case 'B':
+  case 'C':
+  case 'Z':
+  case 'Y':
+    return CW_SpecificReg;
+  }
+  return weight;
+}
+
 /// getRegForInlineAsmConstraint - Return register no and class for a C_Register
 /// constraint.
 std::pair<unsigned, const TargetRegisterClass*> BlackfinTargetLowering::
diff --git a/lib/Target/Blackfin/BlackfinISelLowering.h b/lib/Target/Blackfin/BlackfinISelLowering.h
index 6bebcc320c..15a745fa87 100644
--- a/lib/Target/Blackfin/BlackfinISelLowering.h
+++ b/lib/Target/Blackfin/BlackfinISelLowering.h
@@ -39,6 +39,12 @@ namespace llvm {
                                     SelectionDAG &DAG) const;
 
     ConstraintType getConstraintType(const std::string &Constraint) const;
+
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*>
     getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const;
     std::vector<unsigned>
diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index f594d5d9b7..4e6d39e00a 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -3193,7 +3193,7 @@ static std::string gccifyAsm(std::string asmstr) {
 //      handle communitivity
 void CWriter::visitInlineAsm(CallInst &CI) {
   InlineAsm* as = cast<InlineAsm>(CI.getCalledValue());
-  std::vector<InlineAsm::ConstraintInfo> Constraints = as->ParseConstraints();
+  InlineAsm::ConstraintInfoVector Constraints = as->ParseConstraints();
 
   std::vector<std::pair<Value*, int> > ResultVals;
   if (CI.getType() == Type::getVoidTy(CI.getContext()))
@@ -3213,7 +3213,7 @@ void CWriter::visitInlineAsm(CallInst &CI) {
   bool IsFirst = true;
 
   // Convert over all the output constraints.
-  for (std::vector<InlineAsm::ConstraintInfo>::iterator I = Constraints.begin(),
+  for (InlineAsm::ConstraintInfoVector::iterator I = Constraints.begin(),
        E = Constraints.end(); I != E; ++I) {
 
     if (I->Type != InlineAsm::isOutput) {
@@ -3255,7 +3255,7 @@ void CWriter::visitInlineAsm(CallInst &CI) {
   Out << "\n        :";
   IsFirst = true;
   ValueCount = 0;
-  for (std::vector<InlineAsm::ConstraintInfo>::iterator I = Constraints.begin(),
+  for (InlineAsm::ConstraintInfoVector::iterator I = Constraints.begin(),
        E = Constraints.end(); I != E; ++I) {
     if (I->Type != InlineAsm::isInput) {
       ++ValueCount;
@@ -3284,7 +3284,7 @@ void CWriter::visitInlineAsm(CallInst &CI) {
 
   // Convert over the clobber constraints.
   IsFirst = true;
-  for (std::vector<InlineAsm::ConstraintInfo>::iterator I = Constraints.begin(),
+  for (InlineAsm::ConstraintInfoVector::iterator I = Constraints.begin(),
        E = Constraints.end(); I != E; ++I) {
     if (I->Type != InlineAsm::isClobber)
       continue;  // Ignore non-input constraints.
diff --git a/lib/Target/CellSPU/SPUISelLowering.cpp b/lib/Target/CellSPU/SPUISelLowering.cpp
index 2a82988ce0..eb6134c617 100644
--- a/lib/Target/CellSPU/SPUISelLowering.cpp
+++ b/lib/Target/CellSPU/SPUISelLowering.cpp
@@ -20,6 +20,7 @@
 #include "llvm/Function.h"
 #include "llvm/Intrinsics.h"
 #include "llvm/CallingConv.h"
+#include "llvm/Type.h"
 #include "llvm/CodeGen/CallingConvLower.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
@@ -2989,6 +2990,38 @@ SPUTargetLowering::getConstraintType(const std::string &ConstraintLetter) const
   return TargetLowering::getConstraintType(ConstraintLetter);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+SPUTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;

+    //FIXME: Seems like the supported constraint letters were just copied
+    // from PPC, as the following doesn't correspond to the GCC docs.
+    // I'm leaving it so until someone adds the corresponding lowering support.
+  case 'b':
+  case 'r':
+  case 'f':
+  case 'd':
+  case 'v':
+  case 'y':
+    weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 std::pair<unsigned, const TargetRegisterClass*>
 SPUTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
                                                 EVT VT) const
diff --git a/lib/Target/CellSPU/SPUISelLowering.h b/lib/Target/CellSPU/SPUISelLowering.h
index 23726435b8..41d0826758 100644
--- a/lib/Target/CellSPU/SPUISelLowering.h
+++ b/lib/Target/CellSPU/SPUISelLowering.h
@@ -129,6 +129,11 @@ namespace llvm {
 
     ConstraintType getConstraintType(const std::string &ConstraintLetter) const;
 
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*>
       getRegForInlineAsmConstraint(const std::string &Constraint,
                                    EVT VT) const;
diff --git a/lib/Target/MBlaze/MBlazeISelLowering.cpp b/lib/Target/MBlaze/MBlazeISelLowering.cpp
index a81a01cff5..855060f9ea 100644
--- a/lib/Target/MBlaze/MBlazeISelLowering.cpp
+++ b/lib/Target/MBlaze/MBlazeISelLowering.cpp
@@ -908,6 +908,37 @@ getConstraintType(const std::string &Constraint) const
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+MBlazeTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  const Type *type = CallOperandVal->getType();
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;

+  case 'd':     
+  case 'y': 
+    if (type->isIntegerTy())
+      weight = CW_Register;
+    break;
+  case 'f':
+    if (type->isFloatTy())
+      weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 /// getRegClassForInlineAsmConstraint - Given a constraint letter (e.g. "r"),
 /// return a list of registers that can be used to satisfy the constraint.
 /// This should only be used for C_RegisterClass constraints.
diff --git a/lib/Target/MBlaze/MBlazeISelLowering.h b/lib/Target/MBlaze/MBlazeISelLowering.h
index b900341b67..4f09851e7f 100644
--- a/lib/Target/MBlaze/MBlazeISelLowering.h
+++ b/lib/Target/MBlaze/MBlazeISelLowering.h
@@ -153,6 +153,11 @@ namespace llvm {
     // Inline asm support
     ConstraintType getConstraintType(const std::string &Constraint) const;
 
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*>
               getRegForInlineAsmConstraint(const std::string &Constraint,
               EVT VT) const;
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 6262a0bb2c..5af123219b 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -1269,6 +1269,37 @@ getConstraintType(const std::string &Constraint) const
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+MipsTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  const Type *type = CallOperandVal->getType();
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;
+  case 'd':     
+  case 'y': 
+    if (type->isIntegerTy())
+      weight = CW_Register;
+    break;
+  case 'f':
+    if (type->isFloatTy())
+      weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 /// getRegClassForInlineAsmConstraint - Given a constraint letter (e.g. "r"),
 /// return a list of registers that can be used to satisfy the constraint.
 /// This should only be used for C_RegisterClass constraints.
diff --git a/lib/Target/Mips/MipsISelLowering.h b/lib/Target/Mips/MipsISelLowering.h
index 460747bf54..1e8cc80b64 100644
--- a/lib/Target/Mips/MipsISelLowering.h
+++ b/lib/Target/Mips/MipsISelLowering.h
@@ -139,6 +139,11 @@ namespace llvm {
     // Inline asm support
     ConstraintType getConstraintType(const std::string &Constraint) const;
 
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*> 
               getRegForInlineAsmConstraint(const std::string &Constraint,
               EVT VT) const;
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 0df9fa2df5..7fbbb6f463 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -2473,13 +2473,13 @@ unsigned PrepareCall(SelectionDAG &DAG, SDValue &Callee, SDValue &InFlag,
     // node so that legalize doesn't hack it.
     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
       Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl,
-					  Callee.getValueType());
+            Callee.getValueType());
       needIndirectCall = false;
     }
   }
   if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
       Callee = DAG.getTargetExternalSymbol(S->getSymbol(),
-					   Callee.getValueType());
+             Callee.getValueType());
       needIndirectCall = false;
   }
   if (needIndirectCall) {
@@ -5374,6 +5374,47 @@ PPCTargetLowering::getConstraintType(const std::string &Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
+/// Examine constraint type and operand type and determine a weight value.
+/// This object must already have been set up with the operand type
+/// and the current alternative constraint selected.
+TargetLowering::ConstraintWeight
+PPCTargetLowering::getSingleConstraintMatchWeight(
+    AsmOperandInfo &info, const char *constraint) const {
+  ConstraintWeight weight = CW_Invalid;
+  Value *CallOperandVal = info.CallOperandVal;
+    // If we don't have a value, we can't do a match,
+    // but allow it at the lowest weight.
+  if (CallOperandVal == NULL)
+    return CW_Default;
+  const Type *type = CallOperandVal->getType();
+  // Look at the constraint type.
+  switch (*constraint) {
+  default:
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    break;
+  case 'b':
+    if (type->isIntegerTy())
+      weight = CW_Register;
+    break;
+  case 'f':
+    if (type->isFloatTy())
+      weight = CW_Register;
+    break;
+  case 'd':
+    if (type->isDoubleTy())
+      weight = CW_Register;
+    break;
+  case 'v':
+    if (type->isVectorTy())
+      weight = CW_Register;
+    break;
+  case 'y':
+    weight = CW_Register;
+    break;
+  }
+  return weight;
+}
+
 std::pair<unsigned, const TargetRegisterClass*>
 PPCTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint,
                                                 EVT VT) const {
diff --git a/lib/Target/PowerPC/PPCISelLowering.h b/lib/Target/PowerPC/PPCISelLowering.h
index 700816f5a1..2e1b99b7b1 100644
--- a/lib/Target/PowerPC/PPCISelLowering.h
+++ b/lib/Target/PowerPC/PPCISelLowering.h
@@ -308,6 +308,12 @@ namespace llvm {
                                             bool is8bit, unsigned Opcode) const;
     
     ConstraintType getConstraintType(const std::string &Constraint) const;
+
+    /// Examine constraint string and operand type and determine a weight value.
+    /// The operand object must already have been set up with the operand type.
+    ConstraintWeight getSingleConstraintMatchWeight(
+      AsmOperandInfo &info, const char *constraint) const;
+
     std::pair<unsigned, const TargetRegisterClass*> 
       getRegForInlineAsmConstraint(const std::string &Constraint,
                                    EVT VT) const;
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index d293081449..d8ec6a38f6 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -11428,7 +11428,7 @@ static bool LowerToBSwap(CallInst *CI) {
 
 bool X86TargetLowering::ExpandInlineAsm(CallInst *CI) const {
   InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
-  std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
+  InlineAsm::ConstraintInfoVector Constraints = IA->ParseConstraints();
 
   std::string AsmStr = IA->getAsmString();
 
@@ -11508,18 +11508,32 @@ X86TargetLowering::ConstraintType
 X86TargetLowering::getConstraintType(const std::string &Constraint) const {
   if (Constraint.size() == 1) {
     switch (Constraint[0]) {
-    case 'A':
-      return C_Register;
-    case 'f':
-    case 'r':
     case 'R':
-    case 'l':
     case 'q':
     case 'Q':
-    case 'x':
+    case 'f':
+    case 't':
+    case 'u':
     case 'y':
+    case 'x':
     case 'Y':
       return C_RegisterClass;
+    case 'a':
+    case 'b':
+    case 'c':
+    case 'd':
+    case 'S':
+    case 'D':
+    case 'A':
+      return C_Register;
+    case 'I':
+    case 'J':
+    case 'K':
+    case 'L':
+    case 'M':
+    case 'N':
+    case 'G':
+    case 'C':
     case 'e':
     case 'Z':
       return C_Other;
@@ -11530,30 +11544,106 @@ X86TargetLowering::getConstraintType(const std::string &Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
-/// Examine constraint type and operand type and determine a weight value,
-/// where: -1 = invalid match, and 0 = so-so match to 3 = good match.
+/// Examine constraint type and operand type and determine a weight value.
 /// This object must already have been set up with the operand type
 /// and the current alternative constraint selected.
-int X86TargetLowering::getSingleConstraintMatchWeight(
+TargetLowering::ConstraintWeight
+  X86TargetLowering::getSingleConstraintMatchWeight(
     AsmOperandInfo &info, const char *constraint) const {
-  int weight = -1;
+  ConstraintWeight weight = CW_Invalid;
   Value *CallOperandVal = info.CallOperandVal;
     // If we don't have a value, we can't do a match,
     // but allow it at the lowest weight.
   if (CallOperandVal == NULL)
-    return 0;
+    return CW_Default;
+  const Type *type = CallOperandVal->getType();
   // Look at the constraint type.
   switch (*constraint) {
   default:
-    return TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+    weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
+  case 'R':
+  case 'q':
+  case 'Q':
+  case 'a':
+  case 'b':
+  case 'c':
+  case 'd':
+  case 'S':
+  case 'D':
+  case 'A':
+    if (CallOperandVal->getType()->isIntegerTy())
+      weight = CW_SpecificReg;
+    break;
+  case 'f':
+  case 't':
+  case 'u':
+      if (type->isFloatingPointTy())
+        weight = CW_SpecificReg;
+      break;
+  case 'y':
+      if (type->isX86_MMXTy() && !DisableMMX && Subtarget->hasMMX())
+        weight = CW_SpecificReg;
+      break;
+  case 'x':
+  case 'Y':
+    if ((type->getPrimitiveSizeInBits() == 128) && Subtarget->hasSSE1())
+      weight = CW_Register;
     break;
   case 'I':
     if (ConstantInt *C = dyn_cast<ConstantInt>(info.CallOperandVal)) {
       if (C->getZExtValue() <= 31)
-        weight = 3;
+        weight = CW_Constant;
+    }
+    break;
+  case 'J':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if (C->getZExtValue() <= 63)
+        weight = CW_Constant;
+    }
+    break;
+  case 'K':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if ((C->getSExtValue() >= -0x80) && (C->getSExtValue() <= 0x7f))
+        weight = CW_Constant;
+    }
+    break;
+  case 'L':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if ((C->getZExtValue() == 0xff) || (C->getZExtValue() == 0xffff))
+        weight = CW_Constant;
+    }
+    break;
+  case 'M':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if (C->getZExtValue() <= 3)
+        weight = CW_Constant;
+    }
+    break;
+  case 'N':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if (C->getZExtValue() <= 0xff)
+        weight = CW_Constant;
+    }
+    break;
+  case 'G':
+  case 'C':
+    if (dyn_cast<ConstantFP>(CallOperandVal)) {
+      weight = CW_Constant;
+    }
+    break;
+  case 'e':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if ((C->getSExtValue() >= -0x80000000LL) &&
+          (C->getSExtValue() <= 0x7fffffffLL))
+        weight = CW_Constant;
+    }
+    break;
+  case 'Z':
+    if (ConstantInt *C = dyn_cast<ConstantInt>(CallOperandVal)) {
+      if (C->getZExtValue() <= 0xffffffff)
+        weight = CW_Constant;
     }
     break;
-  // etc.
   }
   return weight;
 }
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index e10c64d7ed..287853f6e8 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -542,10 +542,9 @@ namespace llvm {
 
     ConstraintType getConstraintType(const std::string &Constraint) const;
 
-    /// Examine constraint string and operand type and determine a weight value,
-    /// where: -1 = invalid match, and 0 = so-so match to 3 = good match.
+    /// Examine constraint string and operand type and determine a weight value.
     /// The operand object must already have been set up with the operand type.
-    virtual int getSingleConstraintMatchWeight(
+    virtual ConstraintWeight getSingleConstraintMatchWeight(
       AsmOperandInfo &info, const char *constraint) const;
 
     std::vector<unsigned>