[clang] [AArch64][Clang] Refactor code to emit SVE & SME builtins (PR #70662)

[Sander de Smalen via cfe-commits]

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@@ -9893,24 +9888,40 @@ Value *CodeGenFunction::FormSVEBuiltinResult(Value *Call) {
   return Call;
 }
 
-Value *CodeGenFunction::EmitAArch64SVEBuiltinExpr(unsigned BuiltinID,
-                                                  const CallExpr *E) {
+void CodeGenFunction::GetAArch64SVEProcessedOperands(
+    unsigned BuiltinID, const CallExpr *E, SmallVectorImpl<Value *> &Ops,
+    SVETypeFlags TypeFlags) {
   // Find out if any arguments are required to be integer constant expressions.
   unsigned ICEArguments = 0;
   ASTContext::GetBuiltinTypeError Error;
   getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
   assert(Error == ASTContext::GE_None && "Should not codegen an error");
 
-  llvm::Type *Ty = ConvertType(E->getType());
-  if (BuiltinID >= SVE::BI__builtin_sve_reinterpret_s8_s8 &&
-      BuiltinID <= SVE::BI__builtin_sve_reinterpret_f64_f64) {
-    Value *Val = EmitScalarExpr(E->getArg(0));
-    return EmitSVEReinterpret(Val, Ty);
-  }
+  // Tuple set/get only requires one insert/extract vector, which is
+  // created by EmitSVETupleSetOrGet.
+  bool IsTupleGetOrSet = TypeFlags.isTupleSet() || TypeFlags.isTupleGet();
 
-  llvm::SmallVector<Value *, 4> Ops;
   for (unsigned i = 0, e = E->getNumArgs(); i != e; i++) {
-    if ((ICEArguments & (1 << i)) == 0)
+    bool IsICE = ICEArguments & (1 << i);
+    if (!IsTupleGetOrSet && !IsICE) {
+      Value *Arg = EmitScalarExpr(E->getArg(i));
+      if (auto *VTy = dyn_cast<ScalableVectorType>(Arg->getType())) {
+        unsigned MinElts = VTy->getMinNumElements();
+        bool IsPred = VTy->getElementType()->isIntegerTy(1);
+        unsigned N =
+            (MinElts * VTy->getScalarSizeInBits()) / (IsPred ? 16 : 128);
+        for (unsigned I = 0; I < N; ++I) {
+          Value *Idx = ConstantInt::get(CGM.Int64Ty, (I * MinElts) / N);
+          auto *NewVTy =
+              ScalableVectorType::get(VTy->getElementType(), MinElts / N);
+          if (N == 1 && VTy == NewVTy)
----------------
sdesmalen-arm wrote:

Is `VTy == NewVTy` implied if `N == 1`? If so, can we hoist the `N == 1` check out of the loop?

https://github.com/llvm/llvm-project/pull/70662