Re: [PATCH v1 2/6] Extract ix86 dllimport implementation to mingw

[Richard Sandiford <richard.sandiford@arm.com>]

Evgeny Karpov <Evgeny.Karpov@microsoft.com> writes:
> This patch extracts the ix86 implementation for expanding a SYMBOL
> into its corresponding dllimport, far-address, or refptr symbol.
> It will be reused in the aarch64-w64-mingw32 target.
> The implementation is copied as is from i386/i386.cc with
> minor changes to follow to the code style.
>
> Also this patch replaces the original DLL import/export
> implementation in ix86 with mingw.
>
> gcc/ChangeLog:
>
> 	* config.gcc: Add winnt-dll.o, which contains the DLL
> 	import/export implementation.
> 	* config/i386/cygming.h (SUB_TARGET_RECORD_STUB): Remove the
> 	old implementation. Rename the required function to MinGW.
> 	Rename it to a conditional function that will reuse the
> 	MinGW implementation for COFF and nothing otherwise.
> 	* config/i386/i386-expand.cc (ix86_expand_move): Likewise.
> 	* config/i386/i386-expand.h (is_imported_p): Likewise.
> 	(mingw_GOT_alias_set): Likewise.
> 	(ix86_legitimize_pe_coff_symbol): Likewise.
> 	* config/i386/i386-protos.h: Likewise.
> 	* config/i386/i386.cc (is_imported_p): Likewise.
> 	(ix86_legitimize_pe_coff_symbol): Likewise.
> 	(ix86_GOT_alias_set): Likewise.
> 	(legitimize_pic_address): Likewise.
> 	(struct dllimport_hasher):
> 	(GTY): Likewise.
> 	(get_dllimport_decl): Likewise.
> 	(legitimize_pe_coff_extern_decl): Likewise.
> 	(legitimize_dllimport_symbol): Likewise.
> 	(legitimize_pe_coff_symbol): Likewise.
> 	(ix86_legitimize_address): Likewise.
> 	* config/mingw/winnt.h (mingw_pe_record_stub): Likewise.
> 	* config/mingw/winnt.cc (i386_pe_record_stub): Likewise.
> 	(mingw_pe_record_stub): Likewise.
> 	* config/mingw/t-cygming: Add the winnt-dll.o compilation.
> 	* config/mingw/winnt-dll.cc: New file.

This looks good to me apart from a couple of very minor comments below,
but please get approval from the x86 maintainers as well.  In particular,
they might prefer to handle ix86_legitimize_pe_coff_symbol in some other way.

> [...]
> diff --git a/gcc/config/mingw/winnt-dll.cc b/gcc/config/mingw/winnt-dll.cc
> new file mode 100644
> index 00000000000..349ade6f5c0
> --- /dev/null
> +++ b/gcc/config/mingw/winnt-dll.cc
> @@ -0,0 +1,229 @@
> +/* Expand a SYMBOL into its corresponding dllimport, far-address,
> +or refptr symbol.
> +Copyright (C) 2024 Free Software Foundation, Inc.

I suppose this should retain the range from the i386 file that the
code is moving from:

   Copyright (C) 1988-2024 Free Software Foundation, Inc.

> [...]
> diff --git a/gcc/config/mingw/winnt-dll.h b/gcc/config/mingw/winnt-dll.h
> new file mode 100644
> index 00000000000..19c16e747a2
> --- /dev/null
> +++ b/gcc/config/mingw/winnt-dll.h
> @@ -0,0 +1,26 @@
> +/* Expand a SYMBOL into its corresponding dllimport, far-address,
> +or refptr symbol.
> +Copyright (C) 2024 Free Software Foundation, Inc.
> +
> +GCC is free software; you can redistribute it and/or modify it under
> +the terms of the GNU General Public License as published by the Free
> +Software Foundation; either version 3, or (at your option) any later
> +version.
> +
> +GCC is distributed in the hope that it will be useful, but WITHOUT ANY
> +WARRANTY; without even the implied warranty of MERCHANTABILITY or
> +FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
> +for more details.
> +
> +You should have received a copy of the GNU General Public License
> +along with GCC; see the file COPYING3.  If not see
> +http://www.gnu.org/licenses/.  */
> +
> +#ifndef GCC_MINGW_WINNT_DLL_H
> +#define GCC_MINGW_WINNT_DLL_H
> +
> +extern bool is_imported_p (rtx x);
> +extern alias_set_type mingw_GOT_alias_set (void);
> +extern rtx legitimize_pe_coff_symbol (rtx addr, bool inreg);
> +
> +#endif
> \ No newline at end of file

Would be good to add the newlihe.

Thanks,
Richard