diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index f1b9972..82f5d3a 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -15,6 +15,7 @@
 
 #include "X86.h"
 #include "X86InstrBuilder.h"
+#include "X86ISelLowering.h"
 #include "X86RegisterInfo.h"
 #include "X86Subtarget.h"
 #include "X86TargetMachine.h"
@@ -1493,7 +1494,8 @@
     return false;
 
   // Fast-isel doesn't know about callee-pop yet.
-  if (Subtarget->IsCalleePop(isVarArg, CC))
+  if (X86::isCalleePop(CC, Subtarget->is64Bit(), isVarArg,
+                       GuaranteedTailCallOpt))
     return false;
 
   // Check whether the function can return without sret-demotion.
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 6cd03d0..13bef08 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1898,7 +1898,7 @@
   }
 
   // Some CCs need callee pop.
-  if (Subtarget->IsCalleePop(isVarArg, CallConv)) {
+  if (X86::isCalleePop(CallConv, Is64Bit, isVarArg, GuaranteedTailCallOpt)) {
     FuncInfo->setBytesToPopOnReturn(StackSize); // Callee pops everything.
   } else {
     FuncInfo->setBytesToPopOnReturn(0); // Callee pops nothing.
@@ -2383,7 +2383,7 @@
 
   // Create the CALLSEQ_END node.
   unsigned NumBytesForCalleeToPush;
-  if (Subtarget->IsCalleePop(isVarArg, CallConv))
+  if (X86::isCalleePop(CallConv, Is64Bit, isVarArg, GuaranteedTailCallOpt))
     NumBytesForCalleeToPush = NumBytes;    // Callee pops everything
   else if (!Is64Bit && !IsTailCallConvention(CallConv) && IsStructRet)
     // If this is a call to a struct-return function, the callee
@@ -2876,6 +2876,29 @@
   return false;
 }
 
+/// isCalleePop - Determines whether the callee is required to pop its
+/// own arguments. Callee pop is necessary to support tail calls.
+bool X86::isCalleePop(CallingConv::ID CallingConv,
+                      bool is64Bit, bool IsVarArg, bool TailCallOpt) {
+  if (IsVarArg)
+    return false;
+
+  switch (CallingConv) {
+  default:
+    return false;
+  case CallingConv::X86_StdCall:
+    return !is64Bit;
+  case CallingConv::X86_FastCall:
+    return !is64Bit;
+  case CallingConv::X86_ThisCall:
+    return !is64Bit;
+  case CallingConv::Fast:
+    return TailCallOpt;
+  case CallingConv::GHC:
+    return TailCallOpt;
+  }
+}
+
 /// TranslateX86CC - do a one to one translation of a ISD::CondCode to the X86
 /// specific condition code, returning the condition code and the LHS/RHS of the
 /// comparison to make.
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index d61a125..cbe2389 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -466,6 +466,12 @@
     /// fit into displacement field of the instruction.
     bool isOffsetSuitableForCodeModel(int64_t Offset, CodeModel::Model M,
                                       bool hasSymbolicDisplacement = true);
+
+
+    /// isCalleePop - Determines whether the callee is required to pop its
+    /// own arguments. Callee pop is necessary to support tail calls.
+    bool isCalleePop(CallingConv::ID CallingConv,
+                     bool is64Bit, bool IsVarArg, bool TailCallOpt);
   }
 
   //===--------------------------------------------------------------------===//
diff --git a/lib/Target/X86/X86Subtarget.cpp b/lib/Target/X86/X86Subtarget.cpp
index 481e821..adcf69a 100644
--- a/lib/Target/X86/X86Subtarget.cpp
+++ b/lib/Target/X86/X86Subtarget.cpp
@@ -20,7 +20,6 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
 #include "llvm/ADT/SmallVector.h"
 using namespace llvm;
 
@@ -286,7 +285,7 @@
 }
 
 X86Subtarget::X86Subtarget(const std::string &TT, const std::string &FS, 
-                           bool is64Bit)
+                           bool is64Bit, unsigned StackAlignOverride)
   : PICStyle(PICStyles::None)
   , X86SSELevel(NoMMXSSE)
   , X863DNowLevel(NoThreeDNow)
@@ -308,10 +307,6 @@
   , TargetTriple(TT)
   , Is64Bit(is64Bit) {
 
-  // default to hard float ABI
-  if (FloatABIType == FloatABI::Default)
-    FloatABIType = FloatABI::Hard;
-    
   // Determine default and user specified characteristics
   if (!FS.empty()) {
     // If feature string is not empty, parse features string.
@@ -346,33 +341,9 @@
 
   // Stack alignment is 16 bytes on Darwin, FreeBSD, Linux and Solaris (both
   // 32 and 64 bit) and for all 64-bit targets.
-  if (isTargetDarwin() || isTargetFreeBSD() || isTargetLinux() ||
-      isTargetSolaris() || Is64Bit)
+  if (StackAlignOverride)
+    stackAlignment = StackAlignOverride;
+  else if (isTargetDarwin() || isTargetFreeBSD() || isTargetLinux() ||
+           isTargetSolaris() || Is64Bit)
     stackAlignment = 16;
-
-  if (StackAlignment)
-    stackAlignment = StackAlignment;
-}
-
-/// IsCalleePop - Determines whether the callee is required to pop its
-/// own arguments. Callee pop is necessary to support tail calls.
-bool X86Subtarget::IsCalleePop(bool IsVarArg,
-                               CallingConv::ID CallingConv) const {
-  if (IsVarArg)
-    return false;
-
-  switch (CallingConv) {
-  default:
-    return false;
-  case CallingConv::X86_StdCall:
-    return !is64Bit();
-  case CallingConv::X86_FastCall:
-    return !is64Bit();
-  case CallingConv::X86_ThisCall:
-    return !is64Bit();
-  case CallingConv::Fast:
-    return GuaranteedTailCallOpt;
-  case CallingConv::GHC:
-    return GuaranteedTailCallOpt;
-  }
 }
diff --git a/lib/Target/X86/X86Subtarget.h b/lib/Target/X86/X86Subtarget.h
index 286a798..49bf74b 100644
--- a/lib/Target/X86/X86Subtarget.h
+++ b/lib/Target/X86/X86Subtarget.h
@@ -117,7 +117,8 @@
   /// This constructor initializes the data members to match that
   /// of the specified triple.
   ///
-  X86Subtarget(const std::string &TT, const std::string &FS, bool is64Bit);
+  X86Subtarget(const std::string &TT, const std::string &FS, bool is64Bit,
+               unsigned StackAlignOverride);
 
   /// getStackAlignment - Returns the minimum alignment known to hold of the
   /// stack frame on entry to the function and which must be maintained by every
@@ -248,9 +249,6 @@
   /// indicating the number of scheduling cycles of backscheduling that
   /// should be attempted.
   unsigned getSpecialAddressLatency() const;
-
-  /// IsCalleePop - Test whether a function should pop its own arguments.
-  bool IsCalleePop(bool isVarArg, CallingConv::ID CallConv) const;
 };
 
 } // End llvm namespace
diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp
index 7483329..0b85469 100644
--- a/lib/Target/X86/X86TargetMachine.cpp
+++ b/lib/Target/X86/X86TargetMachine.cpp
@@ -117,7 +117,7 @@
 X86TargetMachine::X86TargetMachine(const Target &T, const std::string &TT,
                                    const std::string &FS, bool is64Bit)
   : LLVMTargetMachine(T, TT),
-    Subtarget(TT, FS, is64Bit),
+    Subtarget(TT, FS, is64Bit, StackAlignment),
     FrameLowering(*this, Subtarget),
     ELFWriterInfo(is64Bit, true) {
   DefRelocModel = getRelocationModel();
@@ -182,6 +182,10 @@
   // Finally, if we have "none" as our PIC style, force to static mode.
   if (Subtarget.getPICStyle() == PICStyles::None)
     setRelocationModel(Reloc::Static);
+
+  // default to hard float ABI
+  if (FloatABIType == FloatABI::Default)
+    FloatABIType = FloatABI::Hard;    
 }
 
 //===----------------------------------------------------------------------===//