[llvm] Add a support for per function CIE (PR #192727)

[Sergei Barannikov via llvm-commits]

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@@ -1979,7 +1979,8 @@ void MCDwarfFrameEmitter::emit(MCObjectStreamer &Streamer, bool IsEH) {
       continue;
 
     CIEKey Key(Frame);
-    if (!LastCIEStart || (IsEH && Key != LastKey)) {
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s-barannikov wrote:

Side question: how can RA registers be different? IIUC it is not currently possible.
https://github.com/llvm/llvm-project/blob/2c67f2fdfc41afd9acfe28e3cb42850a97f1db54/llvm/include/llvm/MC/TargetRegistry.h#L162
This allows you to set different RA registers for different targets but not different subtargets. Do you have other patches downstream that allow doing this?


https://github.com/llvm/llvm-project/pull/192727