[clang] [AArch64] Implement reinterpret builtins for SVE vector tuples (PR #69598)

[via cfe-commits]

================
@@ -64,26 +65,29 @@ class ImmCheck {
 };
 
 class SVEType {
-  TypeSpec TS;
   bool Float, Signed, Immediate, Void, Constant, Pointer, BFloat;
   bool DefaultType, IsScalable, Predicate, PredicatePattern, PrefetchOp,
       Svcount;
   unsigned Bitwidth, ElementBitwidth, NumVectors;
 
 public:
-  SVEType() : SVEType(TypeSpec(), 'v') {}
+  SVEType() : SVEType("", 'v', 0) {}
 
-  SVEType(TypeSpec TS, char CharMod, unsigned NumVectors = 1)
-      : TS(TS), Float(false), Signed(true), Immediate(false), Void(false),
+  SVEType(StringRef TS, char CharMod = 'd', unsigned NumVectors = 0)
----------------
CarolineConcatto wrote:

I know that it only works with 'd'. But it should be able to be empty.
Why NumVectors=0? I believe it still works if we change to 1, so maybe we can reduce some of the changes, for instance lane 918, 970 and 976


https://github.com/llvm/llvm-project/pull/69598