diff options
Diffstat (limited to 'gcc-4.9/gcc/go/go-backend.c')
| -rw-r--r-- | gcc-4.9/gcc/go/go-backend.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/go/go-backend.c b/gcc-4.9/gcc/go/go-backend.c new file mode 100644 index 000000000..de33601db --- /dev/null +++ b/gcc-4.9/gcc/go/go-backend.c @@ -0,0 +1,192 @@ +/* go-backend.c -- Go frontend interface to gcc backend. + Copyright (C) 2010-2014 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC 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 General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "simple-object.h" +#include "tm.h" +#include "tree.h" +#include "stor-layout.h" +#include "tm_p.h" +#include "intl.h" +#include "output.h" /* for assemble_string */ +#include "target.h" +#include "common/common-target.h" + +#include "go-c.h" + +/* The segment name we pass to simple_object_start_read to find Go + export data. */ + +#ifndef GO_EXPORT_SEGMENT_NAME +#define GO_EXPORT_SEGMENT_NAME "__GNU_GO" +#endif + +/* The section name we use when reading and writing export data. */ + +#ifndef GO_EXPORT_SECTION_NAME +#define GO_EXPORT_SECTION_NAME ".go_export" +#endif + +/* This file holds all the cases where the Go frontend needs + information from gcc's backend. */ + +/* Return the alignment in bytes of a struct field of type T. */ + +unsigned int +go_field_alignment (tree t) +{ + unsigned int v; + + v = TYPE_ALIGN (t); + +#ifdef BIGGEST_FIELD_ALIGNMENT + if (v > BIGGEST_FIELD_ALIGNMENT) + v = BIGGEST_FIELD_ALIGNMENT; +#endif + +#ifdef ADJUST_FIELD_ALIGN + { + tree field ATTRIBUTE_UNUSED; + field = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL, t); + v = ADJUST_FIELD_ALIGN (field, v); + } +#endif + + return v / BITS_PER_UNIT; +} + +/* Return the size and alignment of a trampoline. */ + +void +go_trampoline_info (unsigned int *size, unsigned int *alignment) +{ + *size = TRAMPOLINE_SIZE; + *alignment = TRAMPOLINE_ALIGNMENT; +} + +/* This is called by the Go frontend proper if the unsafe package was + imported. When that happens we can not do type-based alias + analysis. */ + +void +go_imported_unsafe (void) +{ + flag_strict_aliasing = false; + + /* Let the backend know that the options have changed. */ + targetm.override_options_after_change (); +} + +/* This is called by the Go frontend proper to add data to the + section containing Go export data. */ + +void +go_write_export_data (const char *bytes, unsigned int size) +{ + static section* sec; + + if (sec == NULL) + { + gcc_assert (targetm_common.have_named_sections); + sec = get_section (GO_EXPORT_SECTION_NAME, SECTION_DEBUG, NULL); + } + + switch_to_section (sec); + assemble_string (bytes, size); +} + +/* The go_read_export_data function is called by the Go frontend + proper to read Go export data from an object file. FD is a file + descriptor open for reading. OFFSET is the offset within the file + where the object file starts; this will be 0 except when reading an + archive. On success this returns NULL and sets *PBUF to a buffer + allocated using malloc, of size *PLEN, holding the export data. If + the data is not found, this returns NULL and sets *PBUF to NULL and + *PLEN to 0. If some error occurs, this returns an error message + and sets *PERR to an errno value or 0 if there is no relevant + errno. */ + +const char * +go_read_export_data (int fd, off_t offset, char **pbuf, size_t *plen, + int *perr) +{ + simple_object_read *sobj; + const char *errmsg; + off_t sec_offset; + off_t sec_length; + int found; + char *buf; + ssize_t c; + + *pbuf = NULL; + *plen = 0; + + sobj = simple_object_start_read (fd, offset, GO_EXPORT_SEGMENT_NAME, + &errmsg, perr); + if (sobj == NULL) + { + /* If we get an error here, just pretend that we didn't find any + export data. This is the right thing to do if the error is + that the file was not recognized as an object file. This + will ignore file I/O errors, but it's not too big a deal + because we will wind up giving some other error later. */ + return NULL; + } + + found = simple_object_find_section (sobj, GO_EXPORT_SECTION_NAME, + &sec_offset, &sec_length, + &errmsg, perr); + simple_object_release_read (sobj); + if (!found) + return errmsg; + + if (lseek (fd, offset + sec_offset, SEEK_SET) < 0) + { + *perr = errno; + return _("lseek failed while reading export data"); + } + + buf = XNEWVEC (char, sec_length); + if (buf == NULL) + { + *perr = errno; + return _("memory allocation failed while reading export data"); + } + + c = read (fd, buf, sec_length); + if (c < 0) + { + *perr = errno; + free (buf); + return _("read failed while reading export data"); + } + + if (c < sec_length) + { + free (buf); + return _("short read while reading export data"); + } + + *pbuf = buf; + *plen = sec_length; + + return NULL; +} |