Adjust for new NaCl startup ABI

sysdeps/i386/dl-machine.h

 /* Machine-dependent ELF dynamic relocation inline functions.  i386 version.
    Copyright (C) 1995-2005, 2006 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,
@@ skipping 165 matching lines @@
 #endif
 
 /* Mask identifying addresses reserved for the user program,
    where the dynamic linker should not map anything.  */
 #define ELF_MACHINE_USER_ADDRESS_MASK   0xf8000000UL
 
 /* Initial entry point code for the dynamic linker.
    The C function `_dl_start' is the real entry point;
    its return value is the user program's entry point.  */
 
+#ifdef __native_client__
+
+/* We're started with the normal C (stack) ABI for a one-argument function.
+   But _dl_start uses regparm, so we have to fetch the argument for it.
+   Our version of _dl_start runs the user's entry point directly, rather
+   than returning it.  */
+
+#define RTLD_START asm("\n\
+        .text\n\
+        .p2align NACLENTRYALIGN\n\
+.globl _start\n\
+_start:\n\
+        movl 4(%esp), %eax\n\
+        jmp _dl_start\n\
+        .previous\n\
+");
+
+#else
+
 #define RTLD_START asm ("\n\
         .text\n\
         .p2align NACLENTRYALIGN\n\
 0:      movl (%esp), %ebx\n\
         popl %ecx; nacljmp %ecx\n\
         .p2align NACLENTRYALIGN\n\
 .globl _start\n\
 .globl _dl_start_user\n\
 _start:\n\
         # Note that _dl_start gets the parameter in %eax.\n\
@@ skipping 27 matching lines @@
         call _dl_init_internal@PLT\n\
         # Pass our finalizer function to the user in %edx, as per ELF ABI.\n\
         leal _dl_fini@GOTOFF(%ebx), %edx\n\
         # Restore %esp _start expects.\n\
         movl (%esp), %esp\n\
         # Jump to the user's entry point.\n\
         nacljmp %edi\n\
         .previous\n\
 ");
 
+#endif
+
 /* Native client PLT does not save %ecx so we cannot use regparm(3). We use
    regparm(2) instead.  */
 
 #ifdef __native_client__
 #define RTLD_LOAD_DL_INIT_PARAMETERS \
         "# Load the parameters again.\n\
         # (eax, edx, *--esp, *--esp) = (_dl_loaded, argc, argv, envp)\n\
         movl _rtld_local@GOTOFF(%ebx), %eax\n\
         leal 8(%esp,%edx,4), %esi\n\
         leal 4(%esp), %ecx\n\
@@ skipping 502 matching lines @@
       td->arg = (void*)reloc;
       td->entry = _dl_tlsdesc_resolve_rela;
     }
   else
     _dl_reloc_bad_type (map, r_type, 1);
 }
 
 #endif  /* !RTLD_BOOTSTRAP */
 
 #endif /* RESOLVE_MAP */