add gnu_triplet_regexp gdbarch method

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.

gdb/ChangeLog
2014-12-12  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.

1 files changed, 17 insertions, 0 deletions

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,
 
 
 
+/* 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)";
+}
+
+
+
 /* 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);
 }
 
 
@@ -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))