elf: Move _dl_setup_hash to its own file

And compile it with the early CFLAGS.  _dl_setup_hash is called
very early for the ld.so link map, so it should be compiled
differently.

Reviewed-by: Stefan Liebler <stli@linux.ibm.com>
Tested-by: Stefan Liebler <stli@linux.ibm.com>

elf/Makefile

@@ -74,6 +74,7 @@ dl-routines = \
   dl-reloc \
   dl-runtime \
   dl-scope \
+  dl-setup_hash \
   dl-sort-maps \
   dl-thread_gscope_wait \
   dl-tls \
@@ -169,6 +170,7 @@ CFLAGS-.os += $(call elide-stack-protector,.os,$(all-rtld-routines))
 
 # Add the requested compiler flags to the early startup code.
 CFLAGS-dl-printf.os += $(rtld-early-cflags)
+CFLAGS-dl-setup_hash.os += $(rtld-early-cflags)
 CFLAGS-dl-sysdep.os += $(rtld-early-cflags)
 CFLAGS-dl-tunables.os += $(rtld-early-cflags)
 CFLAGS-dl-write.os += $(rtld-early-cflags)

elf/dl-lookup.c

@@ -953,51 +953,6 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
 }
 
 
-/* Cache the location of MAP's hash table.  */
-
-void
-_dl_setup_hash (struct link_map *map)
-{
-  Elf_Symndx *hash;
-
-  if (__glibc_likely (map->l_info[ELF_MACHINE_GNU_HASH_ADDRIDX] != NULL))
-    {
-      Elf32_Word *hash32
-	= (void *) D_PTR (map, l_info[ELF_MACHINE_GNU_HASH_ADDRIDX]);
-      map->l_nbuckets = *hash32++;
-      Elf32_Word symbias = *hash32++;
-      Elf32_Word bitmask_nwords = *hash32++;
-      /* Must be a power of two.  */
-      assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
-      map->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
-      map->l_gnu_shift = *hash32++;
-
-      map->l_gnu_bitmask = (ElfW(Addr) *) hash32;
-      hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;
-
-      map->l_gnu_buckets = hash32;
-      hash32 += map->l_nbuckets;
-      map->l_gnu_chain_zero = hash32 - symbias;
-
-      /* Initialize MIPS xhash translation table.  */
-      ELF_MACHINE_XHASH_SETUP (hash32, symbias, map);
-
-      return;
-    }
-
-  if (!map->l_info[DT_HASH])
-    return;
-  hash = (void *) D_PTR (map, l_info[DT_HASH]);
-
-  map->l_nbuckets = *hash++;
-  /* Skip nchain.  */
-  hash++;
-  map->l_buckets = hash;
-  hash += map->l_nbuckets;
-  map->l_chain = hash;
-}
-
-
 static void
 _dl_debug_bindings (const char *undef_name, struct link_map *undef_map,
 		    const ElfW(Sym) **ref, struct sym_val *value,

elf/dl-setup_hash.c

@@ -0,0 +1,63 @@
+/* Cache the location of a link map hash table.
+   Copyright (C) 1995-2022 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/>.  */
+
+#include <assert.h>
+#include <link.h>
+#include <ldsodefs.h>
+
+void
+_dl_setup_hash (struct link_map *map)
+{
+  Elf_Symndx *hash;
+
+  if (__glibc_likely (map->l_info[ELF_MACHINE_GNU_HASH_ADDRIDX] != NULL))
+    {
+      Elf32_Word *hash32
+        = (void *) D_PTR (map, l_info[ELF_MACHINE_GNU_HASH_ADDRIDX]);
+      map->l_nbuckets = *hash32++;
+      Elf32_Word symbias = *hash32++;
+      Elf32_Word bitmask_nwords = *hash32++;
+      /* Must be a power of two.  */
+      assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
+      map->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
+      map->l_gnu_shift = *hash32++;
+
+      map->l_gnu_bitmask = (ElfW(Addr) *) hash32;
+      hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;
+
+      map->l_gnu_buckets = hash32;
+      hash32 += map->l_nbuckets;
+      map->l_gnu_chain_zero = hash32 - symbias;
+
+      /* Initialize MIPS xhash translation table.  */
+      ELF_MACHINE_XHASH_SETUP (hash32, symbias, map);
+
+      return;
+    }
+
+  if (!map->l_info[DT_HASH])
+    return;
+  hash = (void *) D_PTR (map, l_info[DT_HASH]);
+
+  map->l_nbuckets = *hash++;
+  /* Skip nchain.  */
+  hash++;
+  map->l_buckets = hash;
+  hash += map->l_nbuckets;
+  map->l_chain = hash;
+}