Minor cleanup to all the switches after MatchInstructionImpl in all the AsmParsers.

Make sure they all have llvm_unreachable on the default path out of the switch. Remove unnecessary "default: break". Remove a 'return' after unreachable. Fix some indentation.

llvm-svn: 225114
diff --git a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index fb380ed..5885fb1 100644
--- a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -1852,8 +1852,6 @@
       MatchInstructionImpl(Operands, Inst, ErrorInfo, MatchingInlineAsm);
 
   switch (MatchResult) {
-  default:
-    break;
   case Match_Success: {
     if (processInstruction(Inst, IDLoc, Instructions))
       return true;
@@ -1882,7 +1880,8 @@
   case Match_RequiresDifferentSrcAndDst:
     return Error(IDLoc, "source and destination must be different");
   }
-  return true;
+
+  llvm_unreachable("Implement any new match types added!");
 }
 
 void MipsAsmParser::warnIfAssemblerTemporary(int RegIndex, SMLoc Loc) {