[ms-inline asm] Do not omit the frame pointer if we have ms-inline assembly.

If the frame pointer is omitted, and any stack changes occur in the inline
assembly, e.g.: "pusha", then any C local variable or C argument references
will be incorrect.  

I pass no judgement on anyone who would do such a thing. ;)
rdar://13218191

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175334 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MachineFunction.h

@@ -131,6 +131,9 @@ class MachineFunction {
   /// about the control flow of such functions.
   bool ExposesReturnsTwice;
 
+  /// True if the function includes MS-style inline assembly.
+  bool HasMSInlineAsm;
+
   MachineFunction(const MachineFunction &) LLVM_DELETED_FUNCTION;
   void operator=(const MachineFunction&) LLVM_DELETED_FUNCTION;
 public:
@@ -214,6 +217,17 @@ public:
   void setExposesReturnsTwice(bool B) {
     ExposesReturnsTwice = B;
   }
+
+  /// Returns true if the function contains any MS-style inline assembly.
+  bool hasMSInlineAsm() const {
+    return HasMSInlineAsm;
+  }
+
+  /// Set a flag that indicates that the function contains MS-style inline
+  /// assembly.
+  void setHasMSInlineAsm(bool B) {
+    HasMSInlineAsm = B;
+  }
   
   /// getInfo - Keep track of various per-function pieces of information for
   /// backends that would like to do so.

include/llvm/CodeGen/MachineInstr.h

@@ -642,6 +642,9 @@ public:
   bool isKill() const { return getOpcode() == TargetOpcode::KILL; }
   bool isImplicitDef() const { return getOpcode()==TargetOpcode::IMPLICIT_DEF; }
   bool isInlineAsm() const { return getOpcode() == TargetOpcode::INLINEASM; }
+  bool isMSInlineAsm() const { 
+    return getOpcode() == TargetOpcode::INLINEASM && getInlineAsmDialect();
+  }
   bool isStackAligningInlineAsm() const;
   InlineAsm::AsmDialect getInlineAsmDialect() const;
   bool isInsertSubreg() const {