[LLD][COFF] Add support for ARM64EC delay-load imports (#110042)

Fill the regular delay-load IAT with x86_64 delay-load thunks. Similarly
to regular imports, create an auxiliary IAT and its copy for ARM64EC
calls. These are filled with the same `__impchk_` thunks used for
regular imports, which perform an indirect call with
`__icall_helper_arm64ec` on the regular delay-load IAT. These auxiliary
IATs are exposed via CHPE metadata starting from version 2.

The MSVC linker creates one more copy of the auxiliary IAT. `__imp_func`
symbols refer to that hidden IAT, while the `#func` thunk performs a
call with the public auxiliary IAT. If the public auxiliary IAT is fine
for `#func`, it should be fine for calls using the `__imp_func` symbol
as well. Therefore, I made `__imp_func` refer to that IAT too.

0 files changed, 0 insertions, 0 deletions