[clang] [CIR][AArch64] Support BF16/FP16 NEON types and lower vdup lane builtins (PR #187460)

[Andrzej Warzyński via cfe-commits]

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@@ -134,16 +134,14 @@ static cir::VectorType getNeonType(CIRGenFunction *cgf, NeonTypeFlags typeFlags,
                                 v1Ty ? 1 : (4 << isQuad));
   case NeonTypeFlags::BFloat16:
     if (allowBFloatArgsAndRet)
-      cgf->getCIRGenModule().errorNYI(loc, std::string("NEON type: BFloat16"));
-    else
-      cgf->getCIRGenModule().errorNYI(loc, std::string("NEON type: BFloat16"));
-    [[fallthrough]];
+      return cir::VectorType::get(cgf->getCIRGenModule().bFloat16Ty,
+                                  v1Ty ? 1 : (4 << isQuad));
+    return cir::VectorType::get(cgf->uInt16Ty, v1Ty ? 1 : (4 << isQuad));
   case NeonTypeFlags::Float16:
     if (hasLegalHalfType)
-      cgf->getCIRGenModule().errorNYI(loc, std::string("NEON type: Float16"));
-    else
-      cgf->getCIRGenModule().errorNYI(loc, std::string("NEON type: Float16"));
-    [[fallthrough]];
+      return cir::VectorType::get(cgf->getCIRGenModule().fP16Ty,
+                                  v1Ty ? 1 : (4 << isQuad));
+    return cir::VectorType::get(cgf->uInt16Ty, v1Ty ? 1 : (4 << isQuad));
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banach-space wrote:

IIUC, this PR does not require support for `fp16` and this  specific change could be reverted?

https://github.com/llvm/llvm-project/pull/187460