Revert "riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC."

  This one breaks the build, I had it sitting on a branch and must have
forgotten to test it.

This reverts commit 117e8b341c5c0ace8d65feeef136fececb3fdc9c.

Link:https://inbox.sourceware.org/libc-alpha/mhng-0d9fb5a0-63fa-4b02-8029-7c20232f39ee@palmer-ri-x1c9/T/#t
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
I'm ging to put together a build-many-glibcs setup, but that almost
always ends up taking a bit for me.  Happy to just revert this until I
can get one that works, sorry for the headaches.

---
 elf/elf.h                    |  7 -------
 manual/platform.texi         |  6 ------
 sysdeps/riscv/dl-dtprocnum.h | 21 ---------------------
 sysdeps/riscv/dl-machine.h   | 26 --------------------------
 4 files changed, 60 deletions(-)
 delete mode 100644 sysdeps/riscv/dl-dtprocnum.h
  

On Fri, Apr 28, 2023 at 10:55 AM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> This one breaks the build, I had it sitting on a branch and must have
> forgotten to test it.
>
> This reverts commit 117e8b341c5c0ace8d65feeef136fececb3fdc9c.
>
> Link:https://inbox.sourceware.org/libc-alpha/mhng-0d9fb5a0-63fa-4b02-8029-7c20232f39ee@palmer-ri-x1c9/T/#t
> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
> ---
> I'm ging to put together a build-many-glibcs setup, but that almost
> always ends up taking a bit for me.  Happy to just revert this until I
> can get one that works, sorry for the headaches.

I think reverting this will be a cleaner solution!

Reviewed-by: Fangrui Song <maskray@google.com>

> ---
>  elf/elf.h                    |  7 -------
>  manual/platform.texi         |  6 ------
>  sysdeps/riscv/dl-dtprocnum.h | 21 ---------------------
>  sysdeps/riscv/dl-machine.h   | 26 --------------------------
>  4 files changed, 60 deletions(-)
>  delete mode 100644 sysdeps/riscv/dl-dtprocnum.h
>
> diff --git a/elf/elf.h b/elf/elf.h
> index 4f65b5a32d..94ca23c1bb 100644
> --- a/elf/elf.h
> +++ b/elf/elf.h
> @@ -3933,13 +3933,6 @@ enum
>
>  #define R_TILEGX_NUM           130
>
> -/* RISC-V specific values for the Dyn d_tag field.  */
> -#define DT_RISCV_VARIANT_CC    (DT_LOPROC + 1)
> -#define DT_RISCV_NUM           2
> -
> -/* RISC-V specific values for the st_other field.  */
> -#define STO_RISCV_VARIANT_CC 0x80
> -
>  /* RISC-V ELF Flags */
>  #define EF_RISCV_RVC                   0x0001
>  #define EF_RISCV_FLOAT_ABI             0x0006
> diff --git a/manual/platform.texi b/manual/platform.texi
> index 714c07813f..c6ed73cb97 100644
> --- a/manual/platform.texi
> +++ b/manual/platform.texi
> @@ -121,12 +121,6 @@ when it is not allowed, the priority is set to medium.
>  @node RISC-V
>  @appendixsec RISC-V-specific Facilities
>
> -Functions that are lazily bound must be compatible with the standard calling
> -convention. When a function is annotated with STO_RISCV_VARIANT_CC, it means
> -this function is not compatible with the standard calling convention. The
> -dynamic linker will directly resolve it instead of using the lazy binding
> -mechanism.
> -
>  Cache management facilities specific to RISC-V systems that implement the Linux
>  ABI are declared in @file{sys/cachectl.h}.
>
> diff --git a/sysdeps/riscv/dl-dtprocnum.h b/sysdeps/riscv/dl-dtprocnum.h
> deleted file mode 100644
> index 281c5aadeb..0000000000
> --- a/sysdeps/riscv/dl-dtprocnum.h
> +++ /dev/null
> @@ -1,21 +0,0 @@
> -/* Configuration of lookup functions.  RISC-V version.
> -   Copyright (C) 2023 Free Software Foundation, Inc.
> -   This file is part of the GNU C Library.
> -
> -   The GNU C Library is free software; you can redistribute it and/or
> -   modify it under the terms of the GNU Lesser General Public
> -   License as published by the Free Software Foundation; either
> -   version 2.1 of the License, or (at your option) any later version.
> -
> -   The GNU C Library 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
> -   Lesser General Public License for more details.
> -
> -   You should have received a copy of the GNU Lesser General Public
> -   License along with the GNU C Library.  If not, see
> -   <https://www.gnu.org/licenses/>.  */
> -
> -/* Number of extra dynamic section entries for this architecture.  By
> -   default there are none.  */
> -#define DT_THISPROCNUM DT_RISCV_NUM
> diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h
> index 0e6c0bb155..c0c9bd93ad 100644
> --- a/sysdeps/riscv/dl-machine.h
> +++ b/sysdeps/riscv/dl-machine.h
> @@ -53,9 +53,6 @@
>       || (__WORDSIZE == 64 && (type) == R_RISCV_TLS_TPREL64)))  \
>     | (ELF_RTYPE_CLASS_COPY * ((type) == R_RISCV_COPY)))
>
> -//* Translate a processor specific dynamic tag to the index in l_info array.  */
> -#define DT_RISCV(x) (DT_RISCV_##x - DT_LOPROC + DT_NUM)
> -
>  /* Return nonzero iff ELF header is compatible with the running host.  */
>  static inline int __attribute_used__
>  elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
> @@ -284,29 +281,6 @@ elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
>    /* Check for unexpected PLT reloc type.  */
>    if (__glibc_likely (r_type == R_RISCV_JUMP_SLOT))
>      {
> -      if (__glibc_unlikely (map->l_info[DT_RISCV (VARIANT_CC)] != NULL))
> -       {
> -          /* Check the symbol table for variant CC symbols.  */
> -          const Elf_Symndx symndx = ELFW(R_SYM) (reloc->r_info);
> -          const ElfW(Sym) *symtab =
> -            (const void *)D_PTR (map, l_info[DT_SYMTAB]);
> -          const ElfW(Sym) *sym = &symtab[symndx];
> -          if (__glibc_unlikely (sym->st_other & STO_RISCV_VARIANT_CC))
> -            {
> -              /* Avoid lazy resolution of variant CC symbols.  */
> -              const struct r_found_version *version = NULL;
> -              if (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
> -                {
> -                  const ElfW(Half) *vernum =
> -                    (const void *)D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
> -                  version = &map->l_versions[vernum[symndx] & 0x7fff];
> -                }
> -              elf_machine_rela (map, scope, reloc, sym, version, reloc_addr,
> -                                skip_ifunc);
> -              return;
> -            }
> -       }
> -
>        if (__glibc_unlikely (map->l_mach.plt == 0))
>         {
>           if (l_addr)
> --
> 2.40.0
>