[llvm] Use TargetABI to assign default-target features in getDefaultSubtargetFeatures (PR #100833)

[via llvm-commits]

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@@ -81,5 +82,7 @@ void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
       AddFeature("64bit");
       AddFeature("altivec");
     }
+  } else if (Triple.isAndroid() && TargetABI.contains("lp64d")) {
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hiraditya wrote:

> Do we have stability guarantees about the target-abi metadata? I don't think we do, but I also don't recall any changes around it... Is relying on parsing the string stable?

I think there was a patch that added lp* information as metadata in lto/thinlto. So far all the examples I saw also had this information but I can look up the patch if that is needed. At least for the use case I'm looking at this change should be sufficient.

https://github.com/llvm/llvm-project/pull/100833