1 /* Darwin host-specific hook definitions.
2 Copyright (C) 2003-2018 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 "diagnostic-core.h"
24 #include "config/host-darwin.h"
25
26 /* Yes, this is really supposed to work. */
27 static char pch_address_space[1024*1024*1024] __attribute__((aligned (4096)));
28
29 /* Return the address of the PCH address space, if the PCH will fit in it. */
30
31 void *
darwin_gt_pch_get_address(size_t sz,int fd ATTRIBUTE_UNUSED)32 darwin_gt_pch_get_address (size_t sz, int fd ATTRIBUTE_UNUSED)
33 {
34 if (sz <= sizeof (pch_address_space))
35 return pch_address_space;
36 else
37 return NULL;
38 }
39
40 /* Check ADDR and SZ for validity, and deallocate (using munmap) that part of
41 pch_address_space beyond SZ. */
42
43 int
darwin_gt_pch_use_address(void * addr,size_t sz,int fd,size_t off)44 darwin_gt_pch_use_address (void *addr, size_t sz, int fd, size_t off)
45 {
46 const size_t pagesize = getpagesize();
47 void *mmap_result;
48 int ret;
49
50 gcc_assert ((size_t)pch_address_space % pagesize == 0
51 && sizeof (pch_address_space) % pagesize == 0);
52
53 ret = (addr == pch_address_space && sz <= sizeof (pch_address_space));
54 if (! ret)
55 sz = 0;
56
57 /* Round the size to a whole page size. Normally this is a no-op. */
58 sz = (sz + pagesize - 1) / pagesize * pagesize;
59
60 if (munmap (pch_address_space + sz, sizeof (pch_address_space) - sz) != 0)
61 fatal_error (input_location, "couldn%'t unmap pch_address_space: %m");
62
63 if (ret)
64 {
65 mmap_result = mmap (addr, sz,
66 PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_FIXED,
67 fd, off);
68
69 /* The file might not be mmap-able. */
70 ret = mmap_result != (void *) MAP_FAILED;
71
72 /* Sanity check for broken MAP_FIXED. */
73 gcc_assert (!ret || mmap_result == addr);
74 }
75
76 return ret;
77 }
78