This is the mail archive of the
gdb-patches@sources.redhat.com
mailing list for the GDB project.
[COMMIT] User-level threads support for OpenBSD/i386
- From: Mark Kettenis <kettenis at gnu dot org>
- To: gdb-patches at sources dot redhat dot com
- Date: Sun, 23 Jan 2005 20:43:10 +0100 (CET)
- Subject: [COMMIT] User-level threads support for OpenBSD/i386
Subject says it all.
Mark
Index: ChangeLog
from Mark Kettenis <kettenis@gnu.org>
* i386obsd-tdep.c: Update copyright year. Include
"bsd-uthread.h".
(i386obsd_uthread_reg_offset): New variable.
(I386OBSD_UTHREAD_ESP_OFFSET): New define.
(i386obsd_supply_uthread, i386obsd_collect_uthread): New
functions.
(i386obsd_init_abi): Set supply_uthread and collect_uthread.
* Makefile.in (i386obsd-tdep.o): Update dependencies.
* config/i386/obsd.mt (TDEPFILES): Add bsd-uthread.o.
Index: i386obsd-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/i386obsd-tdep.c,v
retrieving revision 1.21
diff -u -p -r1.21 i386obsd-tdep.c
--- i386obsd-tdep.c 31 Oct 2004 19:43:30 -0000 1.21
+++ i386obsd-tdep.c 23 Jan 2005 19:31:42 -0000
@@ -1,7 +1,7 @@
/* Target-dependent code for OpenBSD/i386.
Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002,
- 2003, 2004
+ 2003, 2004, 2005
Free Software Foundation, Inc.
This file is part of GDB.
@@ -38,6 +38,7 @@
#include "i386-tdep.h"
#include "i387-tdep.h"
#include "solib-svr4.h"
+#include "bsd-uthread.h"
/* Support for signal handlers. */
@@ -186,6 +187,120 @@ int i386obsd_sc_reg_offset[I386_NUM_GREG
0 * 4 /* %gs */
};
+/* From /usr/src/lib/libpthread/arch/i386/uthread_machdep.c. */
+static int i386obsd_uthread_reg_offset[] =
+{
+ 11 * 4, /* %eax */
+ 10 * 4, /* %ecx */
+ 9 * 4, /* %edx */
+ 8 * 4, /* %ebx */
+ -1, /* %esp */
+ 6 * 4, /* %ebp */
+ 5 * 4, /* %esi */
+ 4 * 4, /* %edi */
+ 12 * 4, /* %eip */
+ -1, /* %eflags */
+ 13 * 4, /* %cs */
+ -1, /* %ss */
+ 3 * 4, /* %ds */
+ 2 * 4, /* %es */
+ 1 * 4, /* %fs */
+ 0 * 4 /* %gs */
+};
+
+/* Offset within the thread structure where we can find the saved
+ stack pointer (%esp). */
+#define I386OBSD_UTHREAD_ESP_OFFSET 176
+
+static void
+i386obsd_supply_uthread (struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ CORE_ADDR sp_addr = addr + I386OBSD_UTHREAD_ESP_OFFSET;
+ CORE_ADDR sp = 0;
+ char buf[4];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ if (regnum == -1 || regnum == I386_ESP_REGNUM)
+ {
+ int offset;
+
+ /* Fetch stack pointer from thread structure. */
+ sp = read_memory_unsigned_integer (sp_addr, 4);
+
+ /* Adjust the stack pointer such that it looks as if we just
+ returned from _thread_machdep_switch. */
+ offset = i386obsd_uthread_reg_offset[I386_EIP_REGNUM] + 4;
+ store_unsigned_integer (buf, 4, sp + offset);
+ regcache_raw_supply (regcache, I386_ESP_REGNUM, buf);
+ }
+
+ for (i = 0; i < ARRAY_SIZE (i386obsd_uthread_reg_offset); i++)
+ {
+ if (i386obsd_uthread_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ /* Fetch stack pointer from thread structure (if we didn't
+ do so already). */
+ if (sp == 0)
+ sp = read_memory_unsigned_integer (sp_addr, 4);
+
+ /* Read the saved register from the stack frame. */
+ read_memory (sp + i386obsd_uthread_reg_offset[i], buf, 4);
+ regcache_raw_supply (regcache, i, buf);
+ }
+ }
+
+}
+
+static void
+i386obsd_collect_uthread (const struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ CORE_ADDR sp_addr = addr + I386OBSD_UTHREAD_ESP_OFFSET;
+ CORE_ADDR sp = 0;
+ char buf[4];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ if (regnum == -1 || regnum == I386_ESP_REGNUM)
+ {
+ int offset;
+
+ /* Calculate the stack pointer (frame pointer) that will be
+ stored into the thread structure. */
+ offset = i386obsd_uthread_reg_offset[I386_EIP_REGNUM] + 4;
+ regcache_raw_collect (regcache, I386_ESP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 4) - offset;
+
+ /* Store the stack pointer. */
+ write_memory_unsigned_integer (sp_addr, 4, sp);
+
+ /* The stack pointer was (potentially) modified. Make sure we
+ build a proper stack frame. */
+ regnum = -1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE (i386obsd_uthread_reg_offset); i++)
+ {
+ if (i386obsd_uthread_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ /* Fetch stack pointer from thread structure (if we didn't
+ calculate it already). */
+ if (sp == 0)
+ sp = read_memory_unsigned_integer (sp_addr, 4);
+
+ /* Write the register into the stack frame. */
+ regcache_raw_collect (regcache, i, buf);
+ write_memory (sp + i386obsd_uthread_reg_offset[i], buf, 4);
+ }
+ }
+}
+
static void
i386obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
@@ -211,6 +326,10 @@ i386obsd_init_abi (struct gdbarch_info i
original 4.3 BSD. */
tdep->sc_reg_offset = i386obsd_sc_reg_offset;
tdep->sc_num_regs = ARRAY_SIZE (i386obsd_sc_reg_offset);
+
+ /* OpenBSD provides a user-level threads implementation. */
+ bsd_uthread_set_supply_uthread (gdbarch, i386obsd_supply_uthread);
+ bsd_uthread_set_collect_uthread (gdbarch, i386obsd_collect_uthread);
}
/* OpenBSD a.out. */
Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.693
diff -u -p -r1.693 Makefile.in
--- Makefile.in 19 Jan 2005 22:54:55 -0000 1.693
+++ Makefile.in 23 Jan 2005 19:31:45 -0000
@@ -2044,7 +2044,7 @@ i386obsd-nat.o: i386obsd-nat.c $(defs_h)
i386obsd-tdep.o: i386obsd-tdep.c $(defs_h) $(arch_utils_h) $(frame_h) \
$(gdbcore_h) $(regcache_h) $(regset_h) $(symtab_h) $(objfiles_h) \
$(osabi_h) $(target_h) $(gdb_assert_h) $(gdb_string_h) \
- $(i386_tdep_h) $(i387_tdep_h) $(solib_svr4_h)
+ $(i386_tdep_h) $(i387_tdep_h) $(solib_svr4_h) $(bsd_uthread_h)
i386-sol2-nat.o: i386-sol2-nat.c $(defs_h) $(regcache_h) $(gregset_h) \
$(amd64_nat_h) $(amd64_tdep_h)
i386-sol2-tdep.o: i386-sol2-tdep.c $(defs_h) $(value_h) $(osabi_h) \
Index: config/i386/obsd.mt
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/obsd.mt,v
retrieving revision 1.7
diff -u -p -r1.7 obsd.mt
--- config/i386/obsd.mt 13 Sep 2004 20:55:39 -0000 1.7
+++ config/i386/obsd.mt 23 Jan 2005 19:31:45 -0000
@@ -1,4 +1,4 @@
# Target: OpenBSD/i386
TDEPFILES= i386-tdep.o i387-tdep.o i386bsd-tdep.o i386obsd-tdep.o \
- corelow.o solib.o solib-svr4.o
+ bsd-uthread.o corelow.o solib.o solib-svr4.o
DEPRECATED_TM_FILE= solib.h