Bump up MAX_SUBTARGET_FEATURES

[weimingz]

Summary

Currently, ARMGenSubtargetInfo (from ARM.td) is reaching the limit of 96:

enum : uint64_t {
     ...
     XScale = 95
};

We need to bump the maximum value up to accommodate future changes and/or customized subtarget definitions.

[t.p.northover]

104 is a bit of an odd choice (not even an extra byte). I'd just bump it to 128, and hope we can leave it there for a while.

Other than that, sure.

[t.p.northover]

Sorry, it is an extra byte (I've never been one for mental arithmetic: "is a natural number" has always sufficed). I'd still go for 128 though.

[weimingz]

Agree. 128 makes more sense.

[t.p.northover]

Go for it!

Tim.

include/llvm/MC/SubtargetFeature.h

 
 namespace llvm {
   class raw_ostream;
   class StringRef;
 
 // A container class for subtarget features.
 // This is convenient because std::bitset does not have a constructor
 // with an initializer list of set bits.
-const unsigned MAX_SUBTARGET_FEATURES = 96;
+const unsigned MAX_SUBTARGET_FEATURES = 128;
 class FeatureBitset : public std::bitset<MAX_SUBTARGET_FEATURES> {
 public:
   // Cannot inherit constructors because it's not supported by VC++..
   FeatureBitset() : bitset() {}
 
   FeatureBitset(const bitset<MAX_SUBTARGET_FEATURES>& B) : bitset(B) {}
 
   FeatureBitset(std::initializer_list<unsigned> Init) : bitset() {