[clang][ARM] Refactor argument handling in `EmitAArch64BuiltinExpr` (2/2) (NFC) (#181974)
Refactor `EmitAArch64BuiltinExpr` so that all AArch64/NEON builtins
handled by this hook _and marked as overloaded_ share a common path
for generating LLVM IR arguments (collected into the `Ops`
`SmallVector<Value*>`) (*). This is a follow-up for #181794 - please
refer to that PR for more context.
As in the previous PR, the key change is implemented in
`HasExtraNeonArgument` , i.e. in the hook that identifies Builtins with
the extra argument. In this PR, I am replacing the ad-hoc switch
statement with a more principled approach borrowed from SemaARM.cpp,
namely:
```cpp
static bool HasExtraNeonArgument(unsigned BuiltinID) {
// (...)
uint64_t mask = 0;
switch (BuiltinID) {
#define GET_NEON_OVERLOAD_CHECK
#include "clang/Basic/arm_fp16.inc"
#include "clang/Basic/arm_neon.inc"
#undef GET_NEON_OVERLOAD_CHECK
// Non-neon builtins for controling VFP that take extra argument for
// discriminating the type.
case ARM::BI__builtin_arm_vcvtr_f:
case ARM::BI__builtin_arm_vcvtr_d:
mask = 1;
}
switch (BuiltinID) {
default: break;
}
if (mask)
return true;
return false;
```
This is preferred because the extra argument is defined for Sema
verification. CodeGen should reuse the same source of truth rather than
duplicating or partially reimplementing the logic.
No functional change intended.
(*) `EmitAArch64BuiltinExpr` contains two large switch statements
intended to separate handling of non-overloaded and overloaded builtins.
In practice, the split is not consistently enforced. Patch 1/2
refactored the first switch (non-overloaded path). This patch applies
the same cleanup to the overloaded path and completes the refactoring.
llvm-project
0dd1cb01 - [clang][ARM] Refactor argument handling in `EmitAArch64BuiltinExpr` (2/2) (NFC) (#181974)
