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

[Paul Kirth 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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ilovepi 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?

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