Thanks for the update. Parts 1-5 look good to me. Some minor comments
below about part 6:
Evgeny Karpov <evgeny.kar...@microsoft.com> writes:
> This patch reuses the MinGW implementation to enable DLL import/export
> functionality for the aarch64-w64-mingw32 target. It also modifies
> environment configurations for MinGW.
>
> gcc/ChangeLog:
>
> * config.gcc: Add winnt-dll.o, which contains the DLL
> import/export implementation.
> * config/aarch64/aarch64.cc (aarch64_legitimize_pe_coff_symbol):
> Add a conditional function that reuses the MinGW implementation
> for COFF and does nothing otherwise.
> (aarch64_load_symref_appropriately): Add dllimport
> implementation.
> (aarch64_expand_call): Likewise.
> (aarch64_legitimize_address): Likewise.
> * config/aarch64/cygming.h (SYMBOL_FLAG_DLLIMPORT): Modify MinGW
> environment to support DLL import/export.
> (SYMBOL_FLAG_DLLEXPORT): Likewise.
> (SYMBOL_REF_DLLIMPORT_P): Likewise.
> (SYMBOL_FLAG_STUBVAR): Likewise.
> (SYMBOL_REF_STUBVAR_P): Likewise.
> (TARGET_VALID_DLLIMPORT_ATTRIBUTE_P): Likewise.
> (TARGET_ASM_FILE_END): Likewise.
> (SUB_TARGET_RECORD_STUB): Likewise.
> (GOT_ALIAS_SET): Likewise.
> (PE_COFF_EXTERN_DECL_SHOULD_BE_LEGITIMIZED): Likewise.
> (HAVE_64BIT_POINTERS): Likewise.
> ---
> gcc/config.gcc | 4 +++-
> gcc/config/aarch64/aarch64.cc | 37 +++++++++++++++++++++++++++++++++++
> gcc/config/aarch64/cygming.h | 26 ++++++++++++++++++++++--
> 3 files changed, 64 insertions(+), 3 deletions(-)
>
> diff --git a/gcc/config.gcc b/gcc/config.gcc
> index d053b98efa8..331285b7b6d 100644
> --- a/gcc/config.gcc
> +++ b/gcc/config.gcc
> @@ -1276,10 +1276,12 @@ aarch64-*-mingw*)
> tm_file="${tm_file} mingw/mingw32.h"
> tm_file="${tm_file} mingw/mingw-stdint.h"
> tm_file="${tm_file} mingw/winnt.h"
> + tm_file="${tm_file} mingw/winnt-dll.h"
> tmake_file="${tmake_file} aarch64/t-aarch64"
> target_gtfiles="$target_gtfiles \$(srcdir)/config/mingw/winnt.cc"
> + target_gtfiles="$target_gtfiles \$(srcdir)/config/mingw/winnt-dll.cc"
> extra_options="${extra_options} mingw/cygming.opt mingw/mingw.opt"
> - extra_objs="${extra_objs} winnt.o"
> + extra_objs="${extra_objs} winnt.o winnt-dll.o"
> c_target_objs="${c_target_objs} msformat-c.o"
> d_target_objs="${d_target_objs} winnt-d.o"
> tmake_file="${tmake_file} mingw/t-cygming"
> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
> index 3418e57218f..5706b9aeb6b 100644
> --- a/gcc/config/aarch64/aarch64.cc
> +++ b/gcc/config/aarch64/aarch64.cc
> @@ -860,6 +860,10 @@ static const attribute_spec aarch64_gnu_attributes[] =
> { "Advanced SIMD type", 1, 1, false, true, false, true, NULL, NULL },
> { "SVE type", 3, 3, false, true, false, true, NULL, NULL
> },
> { "SVE sizeless type", 0, 0, false, true, false, true, NULL, NULL },
> +#if TARGET_DLLIMPORT_DECL_ATTRIBUTES
> + { "dllimport", 0, 0, false, false, false, false, handle_dll_attribute,
> NULL },
> + { "dllexport", 0, 0, false, false, false, false, handle_dll_attribute,
> NULL },
> +#endif
> #ifdef SUBTARGET_ATTRIBUTE_TABLE
> SUBTARGET_ATTRIBUTE_TABLE
> #endif
> @@ -2819,6 +2823,15 @@ tls_symbolic_operand_type (rtx addr)
> return tls_kind;
> }
>
> +rtx aarch64_legitimize_pe_coff_symbol (rtx addr, bool inreg)
> +{
> +#if TARGET_PECOFF
> + return legitimize_pe_coff_symbol (addr, inreg);
> +#else
> + return NULL_RTX;
> +#endif
> +}
> +
I wondered whether we should try to abstract this behind
SUBTARGET_* stuff, e.g.:
SUBTARGET_LEGITIMIZE_ADDRESS(ADDR) (the inreg==true case)
SUBTARGET_LEGITIMIZE_CALLEE(ADDR) (the inreg==false case)
But I don't think it falls out naturally with the way GCC's code is
organised. I agree having direct references to PECOFF is probably the
least worst option under the circumstances.
Since there is no AArch64-specific handling, I think it'd be
better to have:
#if !TARGET_PECOFF
rtx legitimize_pe_coff_symbol (rtx, bool) { return NULL_RTX; }
#endif
This avoids warning about unused arguments in the !TARGET_PECOFF case.
> /* We'll allow lo_sum's in addresses in our legitimate addresses
> so that combine would take care of combining addresses where
> necessary, but for generation purposes, we'll generate the address
> @@ -2865,6 +2878,17 @@ static void
> aarch64_load_symref_appropriately (rtx dest, rtx imm,
> enum aarch64_symbol_type type)
> {
> + /* If legitimize returns a value
> + copy it directly to the destination and return. */
I don't think the comment really adds anything.
> +
> + rtx tmp = aarch64_legitimize_pe_coff_symbol (imm, true);
> +
Sorry for pushing personal preference, but I think it's slightly
easier to read without this blank line (following the style used
later in aarch64_legitimize_address).
> + if (tmp)
> + {
> + emit_insn (gen_rtx_SET (dest, tmp));
> + return;
Nit: these two lines should be indented by 6 spaces rather than 7.
> + }
> +
> switch (type)
> {
> case SYMBOL_SMALL_ABSOLUTE:
> @@ -11233,6 +11257,12 @@ aarch64_expand_call (rtx result, rtx mem, rtx
> cookie, bool sibcall)
>
> gcc_assert (MEM_P (mem));
> callee = XEXP (mem, 0);
> +
> + tmp = aarch64_legitimize_pe_coff_symbol (callee, false);
> +
Same comment about the blank line here.
> + if (tmp)
> + callee = tmp;
> +
> mode = GET_MODE (callee);
> gcc_assert (mode == Pmode);
>
> @@ -12709,6 +12739,13 @@ aarch64_anchor_offset (HOST_WIDE_INT offset,
> HOST_WIDE_INT size,
> static rtx
> aarch64_legitimize_address (rtx x, rtx /* orig_x */, machine_mode mode)
> {
> + if (TARGET_DLLIMPORT_DECL_ATTRIBUTES)
> + {
> + rtx tmp = aarch64_legitimize_pe_coff_symbol (x, true);
> + if (tmp)
> + return tmp;
> + }
> +
Is there a reason for guarding only this call with
TARGET_DLLIMPORT_DECL_ATTRIBUTES? It seems a bit misleading,
because nothing restricts legitimize_pe_coff_symbol to handling
only the SYMBOL_REF_DLLIMPORT_P case.
If the TARGET_DLLIMPORT_DECL_ATTRIBUTES condition can be dropped, the
series is OK from my POV with that change and with the changes above.
Please get sign-off from an x86 maintainer too though.
Thanks,
Richard
> /* Try to split X+CONST into Y=X+(CONST & ~mask), Y+(CONST&mask),
> where mask is selected by alignment and size of the offset.
> We try to pick as large a range for the offset as possible to
> diff --git a/gcc/config/aarch64/cygming.h b/gcc/config/aarch64/cygming.h
> index 76623153080..e26488735db 100644
> --- a/gcc/config/aarch64/cygming.h
> +++ b/gcc/config/aarch64/cygming.h
> @@ -28,12 +28,18 @@ along with GCC; see the file COPYING3. If not see
>
> #define print_reg(rtx, code, file) (gcc_unreachable ())
>
> -#define SYMBOL_FLAG_DLLIMPORT 0
> -#define SYMBOL_FLAG_DLLEXPORT 0
> +#define SYMBOL_FLAG_DLLIMPORT (SYMBOL_FLAG_MACH_DEP << 0)
> +#define SYMBOL_REF_DLLIMPORT_P(X) \
> + ((SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_DLLIMPORT) != 0)
>
> +#define SYMBOL_FLAG_DLLEXPORT (SYMBOL_FLAG_MACH_DEP << 1)
> #define SYMBOL_REF_DLLEXPORT_P(X) \
> ((SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_DLLEXPORT) != 0)
>
> +#define SYMBOL_FLAG_STUBVAR (SYMBOL_FLAG_MACH_DEP << 2)
> +#define SYMBOL_REF_STUBVAR_P(X) \
> + ((SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_STUBVAR) != 0)
> +
> /* Disable SEH and declare the required SEH-related macros that are
> still needed for compilation. */
> #undef TARGET_SEH
> @@ -59,6 +65,12 @@ still needed for compilation. */
> #define TARGET_ASM_UNIQUE_SECTION mingw_pe_unique_section
> #define TARGET_ENCODE_SECTION_INFO mingw_pe_encode_section_info
>
> +#define TARGET_VALID_DLLIMPORT_ATTRIBUTE_P
> mingw_pe_valid_dllimport_attribute_p
> +
> +/* Output function declarations at the end of the file. */
> +#undef TARGET_ASM_FILE_END
> +#define TARGET_ASM_FILE_END mingw_pe_file_end
> +
> /* Declare the type properly for any external libcall. */
> #define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, FUN) \
> mingw_pe_declare_function_type (FILE, XSTR (FUN, 0), 1)
> @@ -158,6 +170,9 @@ still needed for compilation. */
> { "selectany", 0, 0, true, false, false, false, \
> mingw_handle_selectany_attribute, NULL }
>
> +#undef SUB_TARGET_RECORD_STUB
> +#define SUB_TARGET_RECORD_STUB mingw_pe_record_stub
> +
> #define SUPPORTS_ONE_ONLY 1
>
> /* Define this to be nonzero if static stack checking is supported. */
> @@ -168,4 +183,11 @@ still needed for compilation. */
> #undef MAX_OFILE_ALIGNMENT
> #define MAX_OFILE_ALIGNMENT (8192 * 8)
>
> +#undef GOT_ALIAS_SET
> +#define GOT_ALIAS_SET mingw_GOT_alias_set ()
> +
> +#define PE_COFF_EXTERN_DECL_SHOULD_BE_LEGITIMIZED 1
> +
> +#define HAVE_64BIT_POINTERS 1
> +
> #endif
