[clang] [clang-sycl-linker] AOT-compile split modules concurrently (PR #224548)

[Alexey Bader via cfe-commits]

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@@ -924,6 +925,54 @@ static bool canSkipModuleSplit(IRSplitMode Mode, const Module &M,
   });
 }
 
+/// AOT-compiles every already-produced image in \p SplitModules concurrently
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bader wrote:

What is "already-produced image"?
"JIT image" term sounds more familiar or commonly used.

https://github.com/llvm/llvm-project/pull/224548