[llvm] [BOLT][AArch64] Add support for long absolute LLD thunks/veneers (PR #113408)

[Peter Smith via llvm-commits]

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@@ -29,30 +29,47 @@ static llvm::cl::opt<bool>
 namespace llvm {
 namespace bolt {
 
+static bool isPossibleVeneer(const BinaryFunction &BF) {
+  return BF.isAArch64Veneer() || BF.getOneName().starts_with("__AArch64");
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smithp35 wrote:

I think lld is the only tool putting a prefix of `__AArch64` onto the symbol, if other tools start doing that too then LLD also has a `Thunk` later on in the name, although scanning for that is not likely profitable.

The AbsLongThunks must only be generated in the absence of PIC or PIE so if that can be detected by Bolt then it could be used to rule these out. Whether it is worth doing so or not I don't know.

https://github.com/llvm/llvm-project/pull/113408