[clang] [clang][AIX] Handle triple environment component for per target runtime directory (PR #140850)

[Daniel Chen via cfe-commits]

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@@ -935,6 +935,14 @@ ToolChain::getTargetSubDirPath(StringRef BaseDir) const {
   if (auto Path = getPathForTriple(T))
     return *Path;
 
+  // On AIX, the environment component is not used in the target sub dir name.
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DanielCChen wrote:

We already have a similar code that strip everything after the "base" triple (powerpc[64]-ibm-aix).
https://github.com/llvm/llvm-project/blob/6ed30e6b6b1a1627c554f2ec7c08d5014a21251c/clang/lib/Driver/ToolChain.cpp#L913

I think you can reuse that. 

https://github.com/llvm/llvm-project/pull/140850