[clang] [Clang][AArch64]Refactor typespec handling in SveEmitter.cpp (PR #117717)

[Sander de Smalen via cfe-commits]

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@@ -570,27 +579,35 @@ void SVEType::applyTypespec(StringRef TS) {
   for (char I : TS) {
     switch (I) {
     case 'Q':
+      assert(Kind == Invalid && "Invalid use of modifer!");
       Kind = Svcount;
       break;
     case 'P':
+      assert(Kind == Invalid && "Invalid use of modifer!");
       Kind = Predicate;
       break;
     case 'U':
+      assert(Kind == Invalid && "Invalid use of modifer!");
       Kind = UInt;
       break;
     case 'c':
+      Kind = isInvalid() ? SInt : Kind;
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sdesmalen-arm wrote:

nit: can you also add something like: `assert((Kind == Invalid || Kind == UInt) && "Unexpected modifier used for typespec")`  ?

https://github.com/llvm/llvm-project/pull/117717