gcc/config/host-solaris.c

   1 /* Solaris host-specific hook definitions.
   2    Copyright (C) 2004-2017 Free Software Foundation, Inc.
   3
   4    This file is part of GCC.
   5
   6    GCC is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published
   8    by the Free Software Foundation; either version 3, or (at your
   9    option) any later version.
  10
  11    GCC is distributed in the hope that it will be useful, but WITHOUT
  12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  14    License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GCC; see the file COPYING3.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "hosthooks.h"
  24 #include "hosthooks-def.h"
  25
  26
  27 #undef HOST_HOOKS_GT_PCH_GET_ADDRESS
  28 #define HOST_HOOKS_GT_PCH_GET_ADDRESS sol_gt_pch_get_address
  29 #undef HOST_HOOKS_GT_PCH_USE_ADDRESS
  30 #define HOST_HOOKS_GT_PCH_USE_ADDRESS sol_gt_pch_use_address
  31
  32 /* Before Solaris 11, the mmap ADDR parameter is mostly ignored without
  33    MAP_FIXED set.  Before we give up, search the desired address space with
  34    mincore to see if the space is really free.  */
  35
  36 static void *
  37 mmap_fixed (void *addr, size_t len, int prot, int flags, int fd, off_t off)
  38 {
  39   void *base;
  40
  41   base = mmap ((caddr_t) addr, len, prot, flags, fd, off);
  42
  43   if (base != addr)
  44     {
  45       size_t page_size = getpagesize();
  46       char one_byte;
  47       size_t i;
  48
  49       if (base != (void *) MAP_FAILED)
  50         munmap ((caddr_t) base, len);
  51
  52       errno = 0;
  53       for (i = 0; i < len; i += page_size)
  54         if (mincore ((char *)addr + i, page_size, (char *) &one_byte) == -1
  55             && errno == ENOMEM)
  56           continue; /* The page is not mapped.  */
  57         else
  58           break;
  59
  60       if (i >= len)
  61         base = mmap ((caddr_t) addr, len, prot, flags | MAP_FIXED, fd, off);
  62     }
  63
  64   return base;
  65 }
  66
  67 /* For various ports, try to guess a fixed spot in the vm space
  68    that's probably free.  Based on McDougall, Mauro, Solaris Internals, 2nd
  69    ed., p.460-461, fig. 9-3, 9-4, 9-5.  */
  70 #if defined(__sparcv9__)
  71 /* This low to avoid VA hole on UltraSPARC I/II.  */
  72 # define TRY_EMPTY_VM_SPACE     0x70000000000
  73 #elif defined(__sparc__)
  74 # define TRY_EMPTY_VM_SPACE     0x80000000
  75 #elif defined(__x86_64__)
  76 # define TRY_EMPTY_VM_SPACE     0x80000000000
  77 #elif defined(__i386__)
  78 # define TRY_EMPTY_VM_SPACE     0xB0000000
  79 #else
  80 # define TRY_EMPTY_VM_SPACE     0
  81 #endif
  82
  83 /* Determine a location where we might be able to reliably allocate
  84    SIZE bytes.  FD is the PCH file, though we should return with the
  85    file unmapped.  */
  86
  87 static void *
  88 sol_gt_pch_get_address (size_t size, int fd)
  89 {
  90   void *addr;
  91
  92   addr = mmap_fixed ((caddr_t) TRY_EMPTY_VM_SPACE, size,
  93                      PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
  94
  95   /* If we failed the map, that means there's *no* free space.  */
  96   if (addr == (void *) MAP_FAILED)
  97     return NULL;
  98   /* Unmap the area before returning.  */
  99   munmap ((caddr_t) addr, size);
 100
 101   return addr;
 102 }
 103
 104 /* Map SIZE bytes of FD+OFFSET at BASE.  Return 1 if we succeeded at
 105    mapping the data at BASE, -1 if we couldn't.  */
 106
 107 static int
 108 sol_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
 109 {
 110   void *addr;
 111
 112   /* We're called with size == 0 if we're not planning to load a PCH
 113      file at all.  This allows the hook to free any static space that
 114      we might have allocated at link time.  */
 115   if (size == 0)
 116     return -1;
 117
 118   addr = mmap_fixed ((caddr_t) base, size,
 119                      PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, offset);
 120
 121   return addr == base ? 1 : -1;
 122 }
 123
 124 \f
 125 const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;