Simplify ArchSpec::IsFullySpecifiedTriple() (NFC)

[aprantl]

Summary

I found this function somewhat hard to read and removed a few entirely redundant checks and converted it to early exits.

[JDevlieghere]

LGTM if the answer to both my questions is "yes".

lldb/source/Utility/ArchSpec.cpp

1399

Are you sure that TripleOSWasSpecified() == user_specified_triple.getOS() != llvm::Triple::UnknownOS. Was the check in the original code redundant? Looking at the implementation

bool TripleOSWasSpecified() const { return !m_triple.getOSName().empty(); }

I guess this is identical? But when dealing with triples it's probably worth double checking.

1402

Same for the vendor.

[aprantl]

lldb/source/Utility/ArchSpec.cpp

1399

Great question, yes I checked that. The code for both

https://llvm.org/doxygen/Triple_8cpp_source.html#l00524

is a StringSwitch that uses Unknown as the Default case.

[JDevlieghere]

lldb/source/Utility/ArchSpec.cpp

1399

Thanks for checking!

lldb/source/Utility/ArchSpec.cpp

 }
 
 
 bool lldb_private::operator==(const ArchSpec &lhs, const ArchSpec &rhs) {
   return lhs.GetCore() == rhs.GetCore();
 }
 
 bool ArchSpec::IsFullySpecifiedTriple() const {
-  const auto &user_specified_triple = GetTriple();
+  if (!TripleOSWasSpecified())
+    return false;
 
-  bool user_triple_fully_specified = false;
+  if (!TripleVendorWasSpecified())
+    return false;
 
-  if ((user_specified_triple.getOS() != llvm::Triple::UnknownOS) ||
-      TripleOSWasSpecified()) {
-    if ((user_specified_triple.getVendor() != llvm::Triple::UnknownVendor) ||
-        TripleVendorWasSpecified()) {
-      const unsigned unspecified = 0;
-      if (!user_specified_triple.isOSDarwin() ||
-          user_specified_triple.getOSMajorVersion() != unspecified) {
-        user_triple_fully_specified = true;
-      }
-    }
-  }
+  const llvm::Triple &triple = GetTriple();
+  if (triple.isOSDarwin() && triple.getOSMajorVersion() == unspecified)
+    return false;
 
-  return user_triple_fully_specified;
+  return true;
 }
 
 void ArchSpec::PiecewiseTripleCompare(
     const ArchSpec &other, bool &arch_different, bool &vendor_different,
     bool &os_different, bool &os_version_different, bool &env_different) const {
   const llvm::Triple &me(GetTriple());
   const llvm::Triple &them(other.GetTriple());