[PATCH v4 07/14] add gnu_triplet_regexp gdbarch method

[Jan Kratochvil <jan.kratochvil@redhat.com>]

From: Tom Tromey <tromey@redhat.com>

gdb has to inform libcc1.so of the target being used, so that the
correct compiler can be invoked.  The compiler is invoked using the
GNU configury triplet prefix, e.g., "x86_64-unknown-linux-gnu-gcc".

In order for this to work we need to map the gdbarch to the GNU
configury triplet arch.  In most cases these are identical; however,
the x86 family poses some problems, as the BFD arch names are quite
different from the GNU triplet names.  So, we introduce a new gdbarch
method for this.  A regular expression is used because there are
various valid values for the arch prefix in the triplet.

This patch also updates the osabi code to associate a regular
expression with the OS ABI.  I have only added a concrete value for
Linux.  Note that the "-gnu" part is optional, at least on Fedora it
is omitted from the installed GCC executable's name.

2014-10-07  Tom Tromey  <tromey@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	* osabi.h (osabi_triplet_regexp): Declare.
	* osabi.c (struct osabi_names): New.
	(gdb_osabi_names): Change type to struct osabi_names.  Update
	values.
	(gdbarch_osabi_name): Update.
	(osabi_triplet_regexp): New function.
	(osabi_from_tdesc_string, _initialize_gdb_osabi): Update.
	* i386-tdep.c (i386_gnu_triplet_regexp): New method.
	(i386_elf_init_abi, i386_go32_init_abi, i386_gdbarch_init): Call
	set_gdbarch_gnu_triplet_regexp.
	* gdbarch.sh (gnu_triplet_regexp): New method.
	* gdbarch.c, gdbarch.h: Rebuild.
	* arch-utils.h (default_gnu_triplet_regexp): Declare.
	* arch-utils.c (default_gnu_triplet_regexp): New function.
---
 gdb/ChangeLog    |   18 +++++++++++
 gdb/arch-utils.c |    8 +++++
 gdb/arch-utils.h |    1 +
 gdb/gdbarch.c    |   23 ++++++++++++++
 gdb/gdbarch.h    |   10 ++++++
 gdb/gdbarch.sh   |    7 ++++
 gdb/i386-tdep.c  |   17 ++++++++++
 gdb/osabi.c      |   88 ++++++++++++++++++++++++++++++++++--------------------
 gdb/osabi.h      |    4 ++
 9 files changed, 144 insertions(+), 32 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d62748a..9222c54 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,21 @@
+2014-10-07  Tom Tromey  <tromey@redhat.com>
+	    Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* osabi.h (osabi_triplet_regexp): Declare.
+	* osabi.c (struct osabi_names): New.
+	(gdb_osabi_names): Change type to struct osabi_names.  Update
+	values.
+	(gdbarch_osabi_name): Update.
+	(osabi_triplet_regexp): New function.
+	(osabi_from_tdesc_string, _initialize_gdb_osabi): Update.
+	* i386-tdep.c (i386_gnu_triplet_regexp): New method.
+	(i386_elf_init_abi, i386_go32_init_abi, i386_gdbarch_init): Call
+	set_gdbarch_gnu_triplet_regexp.
+	* gdbarch.sh (gnu_triplet_regexp): New method.
+	* gdbarch.c, gdbarch.h: Rebuild.
+	* arch-utils.h (default_gnu_triplet_regexp): Declare.
+	* arch-utils.c (default_gnu_triplet_regexp): New function.
+
 2014-10-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
 	* arch-utils.c (default_infcall_mmap)
diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index 950912d..ad4d90d 100644
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -855,6 +855,14 @@ default_gcc_target_options (struct gdbarch *gdbarch)
 		     gdbarch_ptr_bit (gdbarch) == 64 ? " -mcmodel=large" : "");
 }
 
+/* gdbarch gnu_triplet_regexp method.  */
+
+const char *
+default_gnu_triplet_regexp (struct gdbarch *gdbarch)
+{
+  return gdbarch_bfd_arch_info (gdbarch)->arch_name;
+}
+
 /* -Wmissing-prototypes */
 extern initialize_file_ftype _initialize_gdbarch_utils;
 
diff --git a/gdb/arch-utils.h b/gdb/arch-utils.h
index 1ccb56a..cb78907 100644
--- a/gdb/arch-utils.h
+++ b/gdb/arch-utils.h
@@ -194,5 +194,6 @@ extern void default_skip_permanent_breakpoint (struct regcache *regcache);
 
 extern CORE_ADDR default_infcall_mmap (CORE_ADDR size, unsigned prot);
 extern char *default_gcc_target_options (struct gdbarch *gdbarch);
+extern const char *default_gnu_triplet_regexp (struct gdbarch *gdbarch);
 
 #endif
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index 7eb1e6b..4cb9fcb 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -320,6 +320,7 @@ struct gdbarch
   gdbarch_vsyscall_range_ftype *vsyscall_range;
   gdbarch_infcall_mmap_ftype *infcall_mmap;
   gdbarch_gcc_target_options_ftype *gcc_target_options;
+  gdbarch_gnu_triplet_regexp_ftype *gnu_triplet_regexp;
 };
 
 /* Create a new ``struct gdbarch'' based on information provided by
@@ -416,6 +417,7 @@ gdbarch_alloc (const struct gdbarch_info *info,
   gdbarch->vsyscall_range = default_vsyscall_range;
   gdbarch->infcall_mmap = default_infcall_mmap;
   gdbarch->gcc_target_options = default_gcc_target_options;
+  gdbarch->gnu_triplet_regexp = default_gnu_triplet_regexp;
   /* gdbarch_alloc() */
 
   return gdbarch;
@@ -640,6 +642,7 @@ verify_gdbarch (struct gdbarch *gdbarch)
   /* Skip verify of vsyscall_range, invalid_p == 0 */
   /* Skip verify of infcall_mmap, invalid_p == 0 */
   /* Skip verify of gcc_target_options, invalid_p == 0 */
+  /* Skip verify of gnu_triplet_regexp, invalid_p == 0 */
   buf = ui_file_xstrdup (log, &length);
   make_cleanup (xfree, buf);
   if (length > 0)
@@ -943,6 +946,9 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
                       "gdbarch_dump: get_syscall_number = <%s>\n",
                       host_address_to_string (gdbarch->get_syscall_number));
   fprintf_unfiltered (file,
+                      "gdbarch_dump: gnu_triplet_regexp = <%s>\n",
+                      host_address_to_string (gdbarch->gnu_triplet_regexp));
+  fprintf_unfiltered (file,
                       "gdbarch_dump: half_bit = %s\n",
                       plongest (gdbarch->half_bit));
   fprintf_unfiltered (file,
@@ -4487,6 +4493,23 @@ set_gdbarch_gcc_target_options (struct gdbarch *gdbarch,
   gdbarch->gcc_target_options = gcc_target_options;
 }
 
+const char *
+gdbarch_gnu_triplet_regexp (struct gdbarch *gdbarch)
+{
+  gdb_assert (gdbarch != NULL);
+  gdb_assert (gdbarch->gnu_triplet_regexp != NULL);
+  if (gdbarch_debug >= 2)
+    fprintf_unfiltered (gdb_stdlog, "gdbarch_gnu_triplet_regexp called\n");
+  return gdbarch->gnu_triplet_regexp (gdbarch);
+}
+
+void
+set_gdbarch_gnu_triplet_regexp (struct gdbarch *gdbarch,
+                                gdbarch_gnu_triplet_regexp_ftype gnu_triplet_regexp)
+{
+  gdbarch->gnu_triplet_regexp = gnu_triplet_regexp;
+}
+
 
 /* Keep a registry of per-architecture data-pointers required by GDB
    modules.  */
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index 304d136..962ef9a 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1356,6 +1356,16 @@ typedef char * (gdbarch_gcc_target_options_ftype) (struct gdbarch *gdbarch);
 extern char * gdbarch_gcc_target_options (struct gdbarch *gdbarch);
 extern void set_gdbarch_gcc_target_options (struct gdbarch *gdbarch, gdbarch_gcc_target_options_ftype *gcc_target_options);
 
+/* Return a regular expression that matches names used by this
+   architecture in GNU configury triplets.  The result is statically
+   allocated and must not be freed.  The default implementation simply
+   returns the BFD architecture name, which is correct in nearly every
+   case. */
+
+typedef const char * (gdbarch_gnu_triplet_regexp_ftype) (struct gdbarch *gdbarch);
+extern const char * gdbarch_gnu_triplet_regexp (struct gdbarch *gdbarch);
+extern void set_gdbarch_gnu_triplet_regexp (struct gdbarch *gdbarch, gdbarch_gnu_triplet_regexp_ftype *gnu_triplet_regexp);
+
 /* Definition for an unknown syscall, used basically in error-cases.  */
 #define UNKNOWN_SYSCALL (-1)
 
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index d3d4e57..f049efc 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -1053,6 +1053,13 @@ f:CORE_ADDR:infcall_mmap:CORE_ADDR size, unsigned prot:size, prot::default_infca
 # These options are put before CU's DW_AT_producer compilation options so that
 # they can override it.  Method may also return NULL.
 m:char *:gcc_target_options:void:::default_gcc_target_options::0
+
+# Return a regular expression that matches names used by this
+# architecture in GNU configury triplets.  The result is statically
+# allocated and must not be freed.  The default implementation simply
+# returns the BFD architecture name, which is correct in nearly every
+# case.
+m:const char *:gnu_triplet_regexp:void:::default_gnu_triplet_regexp::0
 EOF
 }
 
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index 6c4ef17..0750506 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -4306,6 +4306,17 @@ i386_stap_parse_special_token (struct gdbarch *gdbarch,
 
 \f
 
+/* gdbarch gnu_triplet_regexp method.  Both arches are acceptable as GDB always
+   also supplies -m64 or -m32 by gdbarch_gcc_target_options.  */
+
+static const char *
+i386_gnu_triplet_regexp (struct gdbarch *gdbarch)
+{
+  return "(x86_64|i.86)";
+}
+
+\f
+
 /* Generic ELF.  */
 
 void
@@ -4332,6 +4343,8 @@ i386_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 				      i386_stap_is_single_operand);
   set_gdbarch_stap_parse_special_token (gdbarch,
 					i386_stap_parse_special_token);
+
+  set_gdbarch_gnu_triplet_regexp (gdbarch, i386_gnu_triplet_regexp);
 }
 
 /* System V Release 4 (SVR4).  */
@@ -4379,6 +4392,8 @@ i386_go32_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   set_gdbarch_sdb_reg_to_regnum (gdbarch, i386_svr4_reg_to_regnum);
 
   set_gdbarch_has_dos_based_file_system (gdbarch, 1);
+
+  set_gdbarch_gnu_triplet_regexp (gdbarch, i386_gnu_triplet_regexp);
 }
 \f
 
@@ -8402,6 +8417,8 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
      gap for the upper AVX, MPX and AVX512 registers.  */
   set_gdbarch_num_regs (gdbarch, I386_AVX512_NUM_REGS);
 
+  set_gdbarch_gnu_triplet_regexp (gdbarch, i386_gnu_triplet_regexp);
+
   /* Get the x86 target description from INFO.  */
   tdesc = info.target_desc;
   if (! tdesc_has_registers (tdesc))
diff --git a/gdb/osabi.c b/gdb/osabi.c
index d33ef9c..50d391a 100644
--- a/gdb/osabi.c
+++ b/gdb/osabi.c
@@ -41,46 +41,70 @@ static const char *gdb_osabi_available_names[GDB_OSABI_INVALID + 3] = {
 };
 static const char *set_osabi_string;
 
+/* Names associated with each osabi.  */
+
+struct osabi_names
+{
+  /* The "pretty" name.  */
+
+  const char *pretty;
+
+  /* The triplet regexp, or NULL if not known.  */
+
+  const char *regexp;
+};
+
 /* This table matches the indices assigned to enum gdb_osabi.  Keep
    them in sync.  */
-static const char * const gdb_osabi_names[] =
+static const struct osabi_names gdb_osabi_names[] =
 {
-  "none",
-
-  "SVR4",
-  "GNU/Hurd",
-  "Solaris",
-  "GNU/Linux",
-  "FreeBSD a.out",
-  "FreeBSD ELF",
-  "NetBSD a.out",
-  "NetBSD ELF",
-  "OpenBSD ELF",
-  "Windows CE",
-  "DJGPP",
-  "Irix",
-  "HP/UX ELF",
-  "HP/UX SOM",
-  "QNX Neutrino",
-  "Cygwin",
-  "AIX",
-  "DICOS",
-  "Darwin",
-  "Symbian",
-  "OpenVMS",
-  "LynxOS178",
-  "Newlib",
-
-  "<invalid>"
+  { "none", NULL },
+
+  { "SVR4", NULL },
+  { "GNU/Hurd", NULL },
+  { "Solaris", NULL },
+  { "GNU/Linux", "linux(-gnu)?" },
+  { "FreeBSD a.out", NULL },
+  { "FreeBSD ELF", NULL },
+  { "NetBSD a.out", NULL },
+  { "NetBSD ELF", NULL },
+  { "OpenBSD ELF", NULL },
+  { "Windows CE", NULL },
+  { "DJGPP", NULL },
+  { "Irix", NULL },
+  { "HP/UX ELF", NULL },
+  { "HP/UX SOM", NULL },
+  { "QNX Neutrino", NULL },
+  { "Cygwin", NULL },
+  { "AIX", NULL },
+  { "DICOS", NULL },
+  { "Darwin", NULL },
+  { "Symbian", NULL },
+  { "OpenVMS", NULL },
+  { "LynxOS178", NULL },
+  { "Newlib", NULL },
+
+  { "<invalid>", NULL }
 };
 
 const char *
 gdbarch_osabi_name (enum gdb_osabi osabi)
 {
   if (osabi >= GDB_OSABI_UNKNOWN && osabi < GDB_OSABI_INVALID)
-    return gdb_osabi_names[osabi];
+    return gdb_osabi_names[osabi].pretty;
+
+  return gdb_osabi_names[GDB_OSABI_INVALID].pretty;
+}
+
+/* See osabi.h.  */
+
+const char *
+osabi_triplet_regexp (enum gdb_osabi osabi)
+{
+  if (osabi >= GDB_OSABI_UNKNOWN && osabi < GDB_OSABI_INVALID)
+    return gdb_osabi_names[osabi].regexp;
 
-  return gdb_osabi_names[GDB_OSABI_INVALID];
+  return gdb_osabi_names[GDB_OSABI_INVALID].regexp;
 }
 
 /* Lookup the OS ABI corresponding to the specified target description
@@ -92,7 +116,7 @@ osabi_from_tdesc_string (const char *name)
   int i;
 
   for (i = 0; i < ARRAY_SIZE (gdb_osabi_names); i++)
-    if (strcmp (name, gdb_osabi_names[i]) == 0)
+    if (strcmp (name, gdb_osabi_names[i].pretty) == 0)
       {
 	/* See note above: the name table matches the indices assigned
 	   to enum gdb_osabi.  */
@@ -645,7 +669,7 @@ extern initialize_file_ftype _initialize_gdb_osabi; /* -Wmissing-prototype */
 void
 _initialize_gdb_osabi (void)
 {
-  if (strcmp (gdb_osabi_names[GDB_OSABI_INVALID], "<invalid>") != 0)
+  if (strcmp (gdb_osabi_names[GDB_OSABI_INVALID].pretty, "<invalid>") != 0)
     internal_error
       (__FILE__, __LINE__,
        _("_initialize_gdb_osabi: gdb_osabi_names[] is inconsistent"));
diff --git a/gdb/osabi.h b/gdb/osabi.h
index 4c03790..8408f0a 100644
--- a/gdb/osabi.h
+++ b/gdb/osabi.h
@@ -49,6 +49,10 @@ void gdbarch_init_osabi (struct gdbarch_info, struct gdbarch *);
 /* Return the name of the specified OS ABI.  */
 const char *gdbarch_osabi_name (enum gdb_osabi);
 
+/* Return a regular expression that matches the OS part of a GNU
+   configury triplet for the given OSABI.  */
+const char *osabi_triplet_regexp (enum gdb_osabi osabi);
+
 /* Helper routine for ELF file sniffers.  This looks at ABI tag note
    sections to determine the OS ABI from the note.  It should be called
    via bfd_map_over_sections.  */