llvm-project

023b7dad - [CIR] Update the design for structured catch handler representation (#183134)

[CIR] Update the design for structured catch handler representation (#183134) This updates the design for catch handler regions in CIR try operations to add an EH token argument to the regions and to use the `cir.begin_catch` and `cir.end_catch` operations in the structured representation rather than a `cir.catch_param`. This matches the flattened representation and will make flattening easier to implement. This leaves the generation of begin_catch and end_catch operands in the `CXXABI` interface and Itanium implementation. However, because this representation is no longer target-specific, I intend to move this code to `CIRGenFunction` in a future change. I used AI tools to generate many of the changes in this PR, but I have carefully reviewed the changes and updated as needed.