Implement review feedback. Make thumb2 'normal' subtarget feature

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72698 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 96daca8..ef78cd5 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -20,7 +20,8 @@
                            bool isThumb)
   : ARMArchVersion(V4T)
   , ARMFPUType(None)
-  , ThumbMode((isThumb ? Thumb1 : ThumbNone))
+  , IsThumb(isThumb)
+  , ThumbMode(Thumb1)
   , UseThumbBacktraces(false)
   , IsR9Reserved(false)
   , stackAlignment(4)
@@ -41,22 +42,18 @@
   if (Len >= 5 && TT.substr(0, 4) == "armv")
     Idx = 4;
   else if (Len >= 6 && TT.substr(0, 6) == "thumb") {
-    isThumb = true;
+    IsThumb = true;
     if (Len >= 7 && TT[5] == 'v')
       Idx = 6;
   }
   if (Idx) {
     unsigned SubVer = TT[Idx];
     if (SubVer > '4' && SubVer <= '9') {
-      if (SubVer >= '7') {
+      if (SubVer >= '7')
         ARMArchVersion = V7A;
-        if (isThumb)
-          ThumbMode = Thumb2;
-      } else if (SubVer == '6') {
+      else if (SubVer == '6')
         ARMArchVersion = V6;
-        if (isThumb && Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == '2')
-          ThumbMode = Thumb2;
-      } else if (SubVer == '5') {
+      else if (SubVer == '5') {
         ARMArchVersion = V5T;
         if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == 'e')
           ARMArchVersion = V5TE;
diff --git a/lib/Target/ARM/ARMSubtarget.h b/lib/Target/ARM/ARMSubtarget.h
index 370817d..8b469cf 100644
--- a/lib/Target/ARM/ARMSubtarget.h
+++ b/lib/Target/ARM/ARMSubtarget.h
@@ -31,7 +31,6 @@
   };
 
   enum ThumbTypeEnum {
-    ThumbNone,
     Thumb1,
     Thumb2
   };
@@ -43,7 +42,10 @@
   /// ARMFPUType - Floating Point Unit type.
   ARMFPEnum ARMFPUType;
 
-  /// ThumbMode - ARM if in ARM mode, otherwise indicates Thumb version.
+  /// IsThumb - True if we are in thumb mode, false if in ARM mode.
+  bool IsThumb;
+
+  /// ThumbMode - Indicates supported Thumb version.
   ThumbTypeEnum ThumbMode;
 
   /// UseThumbBacktraces - True if we use thumb style backtraces.
@@ -102,8 +104,8 @@
   bool isAPCS_ABI() const { return TargetABI == ARM_ABI_APCS; }
   bool isAAPCS_ABI() const { return TargetABI == ARM_ABI_AAPCS; }
 
-  bool isThumb() const { return ThumbMode >= Thumb1; }
-  bool isThumb2() const { return ThumbMode >= Thumb2; }
+  bool isThumb() const { return IsThumb; }
+  bool isThumb2() const { return IsThumb && (ThumbMode >= Thumb2); }
 
   bool useThumbBacktraces() const { return UseThumbBacktraces; }
   bool isR9Reserved() const { return IsR9Reserved; }