[llvm] [TargetParser] Parse Amazon Linux triple and handle RuntimeLibcalls (PR #136114)

[Fangrui Song via llvm-commits]

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@@ -173,7 +173,7 @@ void RuntimeLibcallsInfo::initLibcalls(const Triple &TT) {
     setLibcallName(RTLIB::EXP10_F64, "__exp10");
   }
 
-  if (TT.isGNUEnvironment() || TT.isOSFuchsia() ||
+  if (TT.isGNUEnvironment() || TT.isOSFuchsia() || TT.isAmazonLinux() ||
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MaskRay wrote:

Thanks for trying multiple solutions.  #140070 looks cleaner and avoids adding isAmazonlinux to other places isGNUEnvironment is used. Will we treat aarch64-amazon-linux-gnu as the triple and prefer it elsewhere? Perhaps yes. 

So we just need a way to recognize the aarch64-amazon-linux gcc installation.

https://github.com/llvm/llvm-project/pull/136114