[llvm][clang] Allocate a new stack instead of spawning a new thread to get more stack space #10628
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…o get more stack space Clang spawns a new thread to avoid running out of stack space. This can make debugging and performance analysis more difficult as how the threads are connected is difficult to recover. This patch introduces `runOnNewStack` and applies it in Clang. On platforms that have good support for it this allocates a new stack and moves to it using assembly. Doing split stacks like this actually runs on most platforms, but many debuggers and unwinders reject the large or backwards stack offsets that occur. Apple platforms and tools are known to support this, so this only enables it there for now. (cherry picked from commit 07deaf8)
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cyndyishida
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May 7, 2025
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Clang spawns a new thread to avoid running out of stack space. This can make debugging and performance analysis more difficult as how the threads are connected is difficult to recover.
This patch introduces
runOnNewStackand applies it in Clang. On platforms that have good support for it this allocates a new stack and moves to it using assembly. Doing split stacks like this actually runs on most platforms, but many debuggers and unwinders reject the large or backwards stack offsets that occur. Apple platforms and tools are known to support this, so this only enables it there for now.(cherry picked from commit 07deaf8)