[Bug tree-optimization/35513] Improve targetm.binds_local_p

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=35513

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by H.J. Lu <hjl@gcc.gnu.org>:

https://gcc.gnu.org/g:ab0b5fbfe90168d2e470aefb19e0cf31526290bc

commit r12-7126-gab0b5fbfe90168d2e470aefb19e0cf31526290bc
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Sat Jun 19 05:12:48 2021 -0700

    x86: Add -m[no-]direct-extern-access

    Add -m[no-]direct-extern-access and nodirect_extern_access attribute.
    -mdirect-extern-access is the default.  With nodirect_extern_access
    attribute, GOT is always used to access undefined data and function
    symbols with nodirect_extern_access attribute, including in PIE and
    non-PIE.  With -mno-direct-extern-access:

    1. Always use GOT to access undefined data and function symbols,
       including in PIE and non-PIE.  These will avoid copy relocations
       in executables.  This is compatible with existing executables and
       shared libraries.
    2. In executable and shared library, bind symbols with the STV_PROTECTED
       visibility locally:
       a. The address of data symbol is the address of data body.
       b. For systems without function descriptor, the function pointer is
          the address of function body.
       c. The resulting shared libraries may not be incompatible with
          executables which have copy relocations on protected symbols or
          use executable PLT entries as function addresses for protected
          functions in shared libraries.
    3. Update asm_preferred_eh_data_format to select PC relative EH encoding
    format with -mno-direct-extern-access to avoid copy relocation.
    4. Add ix86_reloc_rw_mask for TARGET_ASM_RELOC_RW_MASK to avoid copy
    relocation with -mno-direct-extern-access.

    gcc/

            PR target/35513
            PR target/100593
            * config/i386/gnu-property.cc: Include "i386-protos.h".
            (file_end_indicate_exec_stack_and_gnu_property): Generate
            a GNU_PROPERTY_1_NEEDED note for -mno-direct-extern-access or
            nodirect_extern_access attribute.
            * config/i386/i386-options.cc
            (handle_nodirect_extern_access_attribute): New function.
            (ix86_attribute_table): Add nodirect_extern_access attribute.
            * config/i386/i386-protos.h (ix86_force_load_from_GOT_p): Add a
            bool argument.
            (ix86_has_no_direct_extern_access): New.
            * config/i386/i386.cc (ix86_has_no_direct_extern_access): New.
            (ix86_force_load_from_GOT_p): Add a bool argument to indicate
            call operand.  Force non-call load from GOT for
            -mno-direct-extern-access or nodirect_extern_access attribute.
            (legitimate_pic_address_disp_p): Avoid copy relocation in PIE
            for -mno-direct-extern-access or nodirect_extern_access attribute.
            (ix86_print_operand): Pass true to ix86_force_load_from_GOT_p
            for call operand.
            (asm_preferred_eh_data_format): Use PC-relative format for
            -mno-direct-extern-access to avoid copy relocation.  Check
            ptr_mode instead of TARGET_64BIT when selecting DW_EH_PE_sdata4.
            (ix86_binds_local_p): Set ix86_has_no_direct_extern_access to
            true for -mno-direct-extern-access or nodirect_extern_access
            attribute.  Don't treat protected data as extern and avoid copy
            relocation on common symbol with -mno-direct-extern-access or
            nodirect_extern_access attribute.
            (ix86_reloc_rw_mask): New to avoid copy relocation for
            -mno-direct-extern-access.
            (TARGET_ASM_RELOC_RW_MASK): New.
            * config/i386/i386.opt: Add -mdirect-extern-access.
            * doc/extend.texi: Document nodirect_extern_access attribute.
            * doc/invoke.texi: Document -m[no-]direct-extern-access.

    gcc/testsuite/

            PR target/35513
            PR target/100593
            * g++.target/i386/pr35513-1.C: New file.
            * g++.target/i386/pr35513-2.C: Likewise.
            * gcc.target/i386/pr35513-1a.c: Likewise.
            * gcc.target/i386/pr35513-1b.c: Likewise.
            * gcc.target/i386/pr35513-2a.c: Likewise.
            * gcc.target/i386/pr35513-2b.c: Likewise.
            * gcc.target/i386/pr35513-3a.c: Likewise.
            * gcc.target/i386/pr35513-3b.c: Likewise.
            * gcc.target/i386/pr35513-4a.c: Likewise.
            * gcc.target/i386/pr35513-4b.c: Likewise.
            * gcc.target/i386/pr35513-5a.c: Likewise.
            * gcc.target/i386/pr35513-5b.c: Likewise.
            * gcc.target/i386/pr35513-6a.c: Likewise.
            * gcc.target/i386/pr35513-6b.c: Likewise.
            * gcc.target/i386/pr35513-7a.c: Likewise.
            * gcc.target/i386/pr35513-7b.c: Likewise.
            * gcc.target/i386/pr35513-8.c: Likewise.
            * gcc.target/i386/pr35513-9a.c: Likewise.
            * gcc.target/i386/pr35513-9b.c: Likewise.
            * gcc.target/i386/pr35513-10a.c: Likewise.
            * gcc.target/i386/pr35513-10b.c: Likewise.
            * gcc.target/i386/pr35513-11a.c: Likewise.
            * gcc.target/i386/pr35513-11b.c: Likewise.
            * gcc.target/i386/pr35513-12a.c: Likewise.
            * gcc.target/i386/pr35513-12b.c: Likewise.