691a5f3883
CFI: Fix SIGILL reached via trait objects Fix #106547 by transforming the concrete self into a reference to a trait object before emitting type metadata identifiers for trait methods.
The codegen crate contains the code to convert from MIR into LLVM IR,
and then from LLVM IR into machine code. In general it contains code
that runs towards the end of the compilation process.
For more information about how codegen works, see the rustc dev guide.