[clang] [Clang][AArch64] Add fp8 variants for untyped NEON intrinsics (PR #128019)

[Paul Walker via cfe-commits]

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@@ -5464,6 +5464,15 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
           Builder.CreateStore(errorValue, swiftErrorTemp);
         }
 
+        // Mfloat8 type is loaded as scalar type, but is treated as single
+        // vector type for other operations. We need to bitcast it to the vector
+        // type here.
+        if (auto *EltTy =
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paulwalker-arm wrote:

Not sure what the fallout will be from this but I think the problem here is we should not have loaded a scalar in the first place.  Looking at `CodeGenTypes::ConvertTypeForMem()` I can see that we're using a different type for the memory representation than the normal one, which I think is a mistake.

Changing this so the types are consistent will remove the need for this code but I suspect it'll prompt further work elsewhere. My hope is that work sits in target specific areas relating to modelling the builtin so seem reasonable. Please shout though if it starts to get out of control.

https://github.com/llvm/llvm-project/pull/128019