[clang] [lld] [llvm] [WebAssembly] WASIP3 and component model threading support (PR #175800)

[Sy Brand via cfe-commits]

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@@ -79,6 +79,19 @@ static bool WantsPthread(const llvm::Triple &Triple, const ArgList &Args) {
   return WantsPthread;
 }
 
+static bool WantsComponentModelThreadContext(const llvm::Triple &Triple, const ArgList &Args) {
+  // If the target is WASIP3, then enable the
+  // component-model-thread-context feature by default, unless explicitly
+  // disabled.
+  return Triple.getOSName() == "wasip3" &&
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TartanLlama wrote:

Yeah, that makes sense. I've changed it so that the decision is made exactly once for Clang and once for LLVM. So Clang's driver will explicitly supply either +context-model-thread-context or -context-model-thread-context to LLVM, and any users calling `llc` directly or using frontends that don't explicitly set that feature will also get the correct default.

https://github.com/llvm/llvm-project/pull/175800