[PATCH v2] Port GDB to Hurd x86_64.

Flavio Cruz
2024-02-16T01:18:40Z

position of amd64 registers in the different Hurd structs, including
i386_thread_state. The signal code is very similar to i686, except the
trampoline code is adapted.
* gdb/amd64-gnu-tdep.h: export register offsets for x86-gnu-nat.c.
* gdb/config/i386/nm-i386gnu.h: renamed to gdb/config/i386/nm-x86-gnu.h
and adapt it for x86_64.
* gdb/config/i386/i386gnu.mn: renamed to gdb/config/i386/nm-x86-gnu.mn
and reuse it for x86_64.
* gdb/configure.host: recognize gnu64 as a host.
* gdb/configure.nat: recognize gnu64 host and update existing i386gnu to
reuse the new shared files.
* gdb/configure.tgt: recognize x86_64-*-gnu* triplet and use
amd64-gnu-tdep.c.
* gdb/i386-gnu-tdep.c: added i386_gnu_thread_state_reg_offset that is
copied from i386-gnu-nat.c. This makes it similar to amd64.
* gdb/i386-gnu-tdep.h: export register offsets and number of registers.
* gdb/i386-gnu-nat.c: rename it to x86-gnu-nat.c since we reuse this for
i386 and amd64. Updated REG_ADDR to use one of the structures. Added
VALID_REGISTER to make sure it's a register we can provide at this time
(not all of them are available in amd64). FLAGS_REGISTER is either rfl
or efl depending on the arch. Renamed functions and class from i386 to x86
whenever they can be reused.

Tested on Hurd x86_64 and i686.
---

Latest changes:
- Changed svr4_ilp32_fetch_link_map_offsets to
svr4_lp64_fetch_link_map_offsets in amd64-gnu-tdep.c (duh).
- Added set_gdbarch_* to work better with the glibc and shared
library features like TLS and PLT in amd64-gnu-tdep.c and also
i386-gnu-tdep.c

It does seem to work with shared libraries now and I can backtrace inside
library functions from libhurduser up to libc.

gdb/amd64-gnu-tdep.c | 267 ++++++++++++++++++
gdb/amd64-gnu-tdep.h | 29 ++
.../i386/{nm-i386gnu.h => nm-x86-gnu.h} | 7 +
gdb/config/i386/{i386gnu.mn => x86-gnu.mn} | 0
gdb/configure.host | 1 +
gdb/configure.nat | 27 +-
gdb/configure.tgt | 6 +-
gdb/i386-gnu-tdep.c | 47 ++-
gdb/i386-gnu-tdep.h | 29 ++
gdb/{i386-gnu-nat.c => x86-gnu-nat.c} | 128 +++++----
10 files changed, 479 insertions(+), 62 deletions(-)
create mode 100644 gdb/amd64-gnu-tdep.c
create mode 100644 gdb/amd64-gnu-tdep.h
rename gdb/config/i386/{nm-i386gnu.h => nm-x86-gnu.h} (83%)
rename gdb/config/i386/{i386gnu.mn => x86-gnu.mn} (100%)
create mode 100644 gdb/i386-gnu-tdep.h
rename gdb/{i386-gnu-nat.c => x86-gnu-nat.c} (75%)

diff --git a/gdb/amd64-gnu-tdep.c b/gdb/amd64-gnu-tdep.c
new file mode 100644
index 00000000000..a5e67df5f21
--- /dev/null
+++ b/gdb/amd64-gnu-tdep.c
@@ -0,0 +1,267 @@
+/* Target-dependent code for the GNU Hurd.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program 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 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include "defs.h"
+#include "gdbcore.h"
+#include "osabi.h"
+#include "solib-svr4.h"
+
+#include "amd64-tdep.h"
+#include "amd64-gnu-tdep.h"
+#include "glibc-tdep.h"
+
+extern "C"
+{
+#include <mach.h>
+}
+
+/* Recognizing signal handler frames. */
+
+/* When the GNU/Hurd libc calls a signal handler, the return address points
+ inside the trampoline assembly snippet.
+
+ If the trampoline function name can not be identified, we resort to reading
+ memory from the process in order to identify it. */
+
+static const gdb_byte gnu_sigtramp_code[] =
+{
+/* rpc_wait_trampoline: */
+ 0x48, 0xc7, 0xc0, 0xe7, 0xff, 0xff, 0xff, /* mov $-25,%rax */
+ 0x0f, 0x05, /* syscall */
+ 0x49, 0x89, 0x04, 0x24, /* mov %rax,(%r12) */
+ 0x48, 0x89, 0xdc, /* mov %rbx,%rsp */
+
+/* trampoline: */
+ 0x5f, /* pop %rdi */
+ 0x5e, /* pop %rsi */
+ 0x5a, /* pop %rdx */
+ 0x48, 0x83, 0xc4, 0x08, /* add $0x8,%rsp */
+ 0x41, 0xff, 0xd5, /* call *%r13 */
+
+/* RA HERE */
+ 0x48, 0x8b, 0x7c, 0x24, 0x10, /* mov 0x10(%rsp),%rdi */
+ 0xc3, /* ret */
+
+/* firewall: */
+ 0xf4, /* hlt */
+};
+
+#define GNU_SIGTRAMP_LEN (sizeof gnu_sigtramp_code)
+#define GNU_SIGTRAMP_TAIL 7 /* length of tail after RA */
+
+/* If THIS_FRAME is a sigtramp routine, return the address of the
+ start of the routine. Otherwise, return 0. */
+
+static CORE_ADDR
+amd64_gnu_sigtramp_start (frame_info_ptr this_frame)
+{
+ CORE_ADDR pc = get_frame_pc (this_frame);
+ gdb_byte buf[GNU_SIGTRAMP_LEN];
+
+ if (!safe_frame_unwind_memory (this_frame,
+ pc + GNU_SIGTRAMP_TAIL - GNU_SIGTRAMP_LEN,
+ buf))
+ return 0;
+
+ if (memcmp (buf, gnu_sigtramp_code, GNU_SIGTRAMP_LEN) != 0)
+ return 0;
+
+ return pc;
+}
+
+/* Return whether THIS_FRAME corresponds to a Hurd sigtramp routine. */
+
+static int
+amd64_gnu_sigtramp_p (frame_info_ptr this_frame)
+{
+ CORE_ADDR pc = get_frame_pc (this_frame);
+ const char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+
+ /* If we have a NAME, we can check for the trampoline function */
+ if (name != NULL && strcmp (name, "trampoline") == 0)
+ return 1;
+
+ return amd64_gnu_sigtramp_start (this_frame) != 0;
+}
+
+/* Offset to sc_i386_thread_state in sigcontext, from <bits/sigcontext.h>. */
+#define AMD64_GNU_SIGCONTEXT_THREAD_STATE_OFFSET 32
+
+/* Assuming THIS_FRAME is a Hurd sigtramp routine, return the
+ address of the associated sigcontext structure. */
+
+static CORE_ADDR
+amd64_gnu_sigcontext_addr (frame_info_ptr this_frame)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ CORE_ADDR pc;
+ CORE_ADDR sp;
+ gdb_byte buf[8];
+
+ get_frame_register (this_frame, AMD64_RSP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 8, byte_order);
+
+ pc = amd64_gnu_sigtramp_start (this_frame);
+ if (pc)
+ {
+ CORE_ADDR sigcontext_addr;
+
+ /* The sigcontext structure address is passed as the third argument
+ * of the signal handler but %RDX is not saved across calls. Luckily,
+ * the structured is saved underneath the &__sigreturn and a dummy word
+ * to fill the slot for the address for __sigreturn to return to.
+ */
+ read_memory (sp + 16, buf, 8);
+ sigcontext_addr = extract_unsigned_integer (buf, 8, byte_order);
+ return sigcontext_addr + AMD64_GNU_SIGCONTEXT_THREAD_STATE_OFFSET;
+ }
+
+ error (_("Couldn't recognize signal trampoline."));
+ return 0;
+}
+
+/* Mapping between the general-purpose registers in `struct
+ sigcontext' format (starting at sc_i386_thread_state)
+ and GDB's register cache layout. */
+
+/* From <bits/sigcontext.h>. */
+static int amd64_gnu_sc_reg_offset[] =
+{
+ 15 * 8, /* %rax */
+ 12 * 8, /* %rbx */
+ 14 * 8, /* %rcx */
+ 13 * 8, /* %rdx */
+ 10 * 8, /* %rsi */
+ 9 * 8, /* %rdi */
+ 10 * 8, /* %rbp */
+ 11 * 8, /* %rsp */
+ 0 * 8, /* %r8 ... */
+ 8 * 8,
+ 7 * 8,
+ 6 * 8,
+ 3 * 8,
+ 2 * 8,
+ 1 * 8,
+ 0 * 8, /* ... %r15 */
+ 16 * 8, /* %rip */
+ 18 * 8, /* %eflags */
+ 17 * 8, /* %cs */
+};
+
+/* From <sys/ucontext.h>. */
+static int amd64_gnu_gregset_reg_offset[] =
+{
+ 10 * 8, /* %rax */
+ 5 * 8, /* %rbx */
+ 11 * 8, /* %rcx */
+ 12 * 8, /* %rdx */
+ 13 * 8, /* %rsi */
+ 14 * 8, /* %rdi */
+ 4 * 8, /* %rbp */
+ 19 * 8, /* %rsp */
+ 9 * 8, /* %r8 ... */
+ 8 * 8,
+ 7 * 8,
+ 6 * 8,
+ 3 * 8,
+ 2 * 8,
+ 1 * 8,
+ 0 * 8, /* ... %r15 */
+ 16 * 8, /* %rip */
+ 18 * 8, /* %eflags */
+ 17 * 8, /* %cs */
+ -1, /* %ss */
+ -1, /* %ds */
+ -1, /* %es */
+ -1, /* %fs */
+ -1, /* %gs */
+};
+
+/* Offset to the thread_state_t location where REG is stored. */
+#define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
+
+/* At REG_OFFSET[N] is the offset to the thread_state_t location where
+ the GDB register N is stored. */
+int amd64_gnu_thread_state_reg_offset[] =
+{
+ REG_OFFSET (rax), /* %rax */
+ REG_OFFSET (rbx), /* %rbx */
+ REG_OFFSET (rcx), /* %rcx */
+ REG_OFFSET (rdx), /* %rdx */
+ REG_OFFSET (rsi), /* %rsi */
+ REG_OFFSET (rdi), /* %rdi */
+ REG_OFFSET (rbp), /* %rbp */
+ REG_OFFSET (ursp), /* %rsp */
+ REG_OFFSET (r8), /* %r8 ... */
+ REG_OFFSET (r9),
+ REG_OFFSET (r10),
+ REG_OFFSET (r11),
+ REG_OFFSET (r12),
+ REG_OFFSET (r13),
+ REG_OFFSET (r14),
+ REG_OFFSET (r15), /* ... %r15 */
+ REG_OFFSET (rip), /* %rip */
+ REG_OFFSET (rfl), /* %rflags */
+ REG_OFFSET (cs) /* %cs */
+};
+
+const int amd64_gnu_thread_state_num_regs =
+ ARRAY_SIZE (amd64_gnu_thread_state_reg_offset);
+
+static void
+amd64_gnu_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch);
+
+ amd64_init_abi (info, gdbarch,
+ amd64_target_description (X86_XSTATE_SSE_MASK, true));
+
+ /* Enable TLS support. */
+ set_gdbarch_fetch_tls_load_module_address (gdbarch,
+ svr4_fetch_objfile_link_map);
+
+ /* Hurd uses SVR4-style shared libraries. */
+ set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
+
+ /* Hurd uses the dynamic linker included in the GNU C Library. */
+ set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
+
+ tdep->gregset_reg_offset = amd64_gnu_gregset_reg_offset;
+ tdep->gregset_num_regs = ARRAY_SIZE (amd64_gnu_gregset_reg_offset);
+ tdep->sizeof_gregset = 21 * 8; /* sizeof (struct i386_thread_state); */
+
+ tdep->sigtramp_p = amd64_gnu_sigtramp_p;
+ tdep->sigcontext_addr = amd64_gnu_sigcontext_addr;
+ tdep->sc_reg_offset = amd64_gnu_sc_reg_offset;
+ tdep->sc_num_regs = ARRAY_SIZE (amd64_gnu_sc_reg_offset);
+
+ /* Hurd uses SVR4-style shared libraries. */
+ set_solib_svr4_fetch_link_map_offsets
+ (gdbarch, svr4_lp64_fetch_link_map_offsets);
+}
+
+void _initialize_amd64_gnu_tdep ();
+void
+_initialize_amd64_gnu_tdep ()
+{
+ gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
+ GDB_OSABI_HURD, amd64_gnu_init_abi);
+}
diff --git a/gdb/amd64-gnu-tdep.h b/gdb/amd64-gnu-tdep.h
new file mode 100644
index 00000000000..70a6e4bfeb6
--- /dev/null
+++ b/gdb/amd64-gnu-tdep.h
@@ -0,0 +1,29 @@
+/* Target-dependent code for Hurd x86-64.
+
+ Copyright (C) 2024 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program 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 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef AMD64_GNU_TDEP_H
+#define AMD64_GNU_TDEP_H
+
+/* Mapping between the general-purpose registers in Hurd x86_64 thread
+ state and GDB's register cache layout.
+ Indexed by amd64_regnum. */
+extern int amd64_gnu_thread_state_reg_offset[];
+extern const int amd64_gnu_thread_state_num_regs;
+
+#endif /* AMD64_GNU_TDEP_H */
diff --git a/gdb/config/i386/nm-i386gnu.h b/gdb/config/i386/nm-x86-gnu.h
similarity index 83%
rename from gdb/config/i386/nm-i386gnu.h
rename to gdb/config/i386/nm-x86-gnu.h
index d2d5de83948..ed4d1729227 100644
--- a/gdb/config/i386/nm-i386gnu.h
+++ b/gdb/config/i386/nm-x86-gnu.h
@@ -22,9 +22,16 @@
/* Thread flavors used in re-setting the T bit. */
#define THREAD_STATE_FLAVOR i386_REGS_SEGS_STATE
#define THREAD_STATE_SIZE i386_THREAD_STATE_COUNT
+#ifdef __x86_64__
+#define THREAD_STATE_SET_TRACED(state) \
+ ((struct i386_thread_state *) (state))->rfl |= 0x100
+#define THREAD_STATE_CLEAR_TRACED(state) \
+ ((((struct i386_thread_state *) (state))->rfl &= ~0x100), 1)
+#else
#define THREAD_STATE_SET_TRACED(state) \
((struct i386_thread_state *) (state))->efl |= 0x100
#define THREAD_STATE_CLEAR_TRACED(state) \
((((struct i386_thread_state *) (state))->efl &= ~0x100), 1)
+#endif /* __x86_64__ */

#endif /* CONFIG_I386_NM_I386GNU_H */
diff --git a/gdb/config/i386/i386gnu.mn b/gdb/config/i386/x86-gnu.mn
similarity index 100%
rename from gdb/config/i386/i386gnu.mn
rename to gdb/config/i386/x86-gnu.mn
diff --git a/gdb/configure.host b/gdb/configure.host
index da71675b201..999af8e59ae 100644
--- a/gdb/configure.host
+++ b/gdb/configure.host
@@ -184,6 +184,7 @@ x86_64-*-mingw*) gdb_host=mingw64
gdb_host_obs=mingw-hdep.o
;;
x86_64-*-cygwin*) gdb_host=cygwin64 ;;
+x86_64-*-gnu*) gdb_host=gnu64 ;;
m32r*-*-linux*) gdb_host=linux ;;

xtensa*-*-linux*) gdb_host=linux ;;
diff --git a/gdb/configure.nat b/gdb/configure.nat
index 8b98511cef7..ef404fb791a 100644
--- a/gdb/configure.nat
+++ b/gdb/configure.nat
@@ -211,23 +211,44 @@ case ${gdb_host} in
;;
esac
;;
+ gnu64)
+ case ${gdb_host_cpu} in
+ i386)
+ # Host: x86_64 running the GNU Hurd
+ NATDEPFILES='x86-gnu-nat.o gnu-nat.o \
+ x86-nat.o nat/x86-dregs.o nat/x86-xstate.o \
+ amd64-nat.o fork-child.o \
+ nat/fork-inferior.o \
+ notify_S.o process_reply_S.o msg_reply_S.o \
+ msg_U.o exc_request_U.o exc_request_S.o'
+ HAVE_NATIVE_GCORE_HOST=1
+
+ NAT_FILE='nm-x86-gnu.h'
+ MH_CFLAGS='-D_GNU_SOURCE'
+
+ XM_CLIBS='-lshouldbeinlibc'
+
+ nat_makefile_frag="${srcdir}/config/${gdb_host_cpu}/x86-gnu.mn"
+ ;;
+ esac
+ ;;
i386gnu)
case ${gdb_host_cpu} in
i386)
# Host: Intel 386 running the GNU Hurd
- NATDEPFILES='i386-gnu-nat.o gnu-nat.o \
+ NATDEPFILES='x86-gnu-nat.o gnu-nat.o \
x86-nat.o nat/x86-dregs.o fork-child.o \
nat/fork-inferior.o \
notify_S.o process_reply_S.o msg_reply_S.o \
msg_U.o exc_request_U.o exc_request_S.o'
HAVE_NATIVE_GCORE_HOST=1

- NAT_FILE='nm-i386gnu.h'
+ NAT_FILE='nm-x86-gnu.h'
MH_CFLAGS='-D_GNU_SOURCE'

XM_CLIBS='-lshouldbeinlibc'

- nat_makefile_frag="${srcdir}/config/${gdb_host_cpu}/i386gnu.mn"
+ nat_makefile_frag="${srcdir}/config/${gdb_host_cpu}/x86-gnu.mn"
;;
esac
;;
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 47a674201f9..df9e9917ad1 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -328,7 +328,7 @@ i[34567]86-*-linux*)
;;
i[34567]86-*-gnu*)
# Target: Intel 386 running the GNU Hurd
- gdb_target_obs="i386-gnu-tdep.o solib-svr4.o"
+ gdb_target_obs="i386-gnu-tdep.o glibc-tdep.o solib-svr4.o"
;;
i[34567]86-*-cygwin*)
# Target: Intel 386 running win32
@@ -744,6 +744,10 @@ x86_64-*-openbsd*)
x86_64-*-rtems*)
gdb_target_obs="${amd64_tobjs} ${i386_tobjs} i386-bsd-tdep.o"
;;
+x86_64-*-gnu*)
+ # Target: x86_64 running the GNU Hurd
+ gdb_target_obs="amd64-gnu-tdep.o glibc-tdep.o solib-svr4.o"
+ ;;
xtensa*-*-*linux*)
# Target: GNU/Linux Xtensa
gdb_target_obs="xtensa-linux-tdep.o symfile-mem.o linux-tdep.o"
diff --git a/gdb/i386-gnu-tdep.c b/gdb/i386-gnu-tdep.c
index 9ff47147513..d0d9059e883 100644
--- a/gdb/i386-gnu-tdep.c
+++ b/gdb/i386-gnu-tdep.c
@@ -21,7 +21,14 @@
#include "osabi.h"
#include "solib-svr4.h"

+#include "glibc-tdep.h"
#include "i386-tdep.h"
+#include "i386-gnu-tdep.h"
+
+extern "C"
+{
+#include <mach.h>
+}

/* Recognizing signal handler frames. */

@@ -72,8 +79,7 @@ i386_gnu_sigtramp_start (frame_info_ptr this_frame)
return pc;
}

-/* Return whether THIS_FRAME corresponds to a GNU/Linux sigtramp
- routine. */
+/* Return whether THIS_FRAME corresponds to a Hurd sigtramp routine. */

static int
i386_gnu_sigtramp_p (frame_info_ptr this_frame)
@@ -170,6 +176,34 @@ static int i386gnu_gregset_reg_offset[] =
0 * 4, /* %gs */
};

+/* Offset to the thread_state_t location where REG is stored. */
+#define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
+
+/* At REG_OFFSET[N] is the offset to the thread_state_t location where
+ the GDB register N is stored. */
+int i386_gnu_thread_state_reg_offset[] =
+{
+ REG_OFFSET (eax), /* %eax */
+ REG_OFFSET (ecx), /* %ecx */
+ REG_OFFSET (edx), /* %edx */
+ REG_OFFSET (ebx), /* %ebx */
+ REG_OFFSET (uesp), /* %esp */
+ REG_OFFSET (ebp), /* %ebp */
+ REG_OFFSET (esi), /* %esi */
+ REG_OFFSET (edi), /* %edi */
+ REG_OFFSET (eip), /* %eip */
+ REG_OFFSET (efl), /* %efl */
+ REG_OFFSET (cs), /* %cs */
+ REG_OFFSET (ss), /* %ss */
+ REG_OFFSET (ds), /* %ds */
+ REG_OFFSET (es), /* %es */
+ REG_OFFSET (fs), /* %fs */
+ REG_OFFSET (gs) /* gs */
+};
+
+const int i386_gnu_thread_state_num_regs =
+ ARRAY_SIZE (i386_gnu_thread_state_reg_offset);
+
static void
i386gnu_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
@@ -178,9 +212,18 @@ i386gnu_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
/* GNU uses ELF. */
i386_elf_init_abi (info, gdbarch);

+ /* Hurd uses SVR4-style shared libraries. */
+ set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);

+ /* Hurd uses the dynamic linker included in the GNU C Library. */
+ set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
+
+ /* Enable TLS support. */
+ set_gdbarch_fetch_tls_load_module_address (gdbarch,
+ svr4_fetch_objfile_link_map);
+
tdep->gregset_reg_offset = i386gnu_gregset_reg_offset;
tdep->gregset_num_regs = ARRAY_SIZE (i386gnu_gregset_reg_offset);
tdep->sizeof_gregset = 19 * 4;
diff --git a/gdb/i386-gnu-tdep.h b/gdb/i386-gnu-tdep.h
new file mode 100644
index 00000000000..32e9a73c667
--- /dev/null
+++ b/gdb/i386-gnu-tdep.h
@@ -0,0 +1,29 @@
+/* Target-dependent code for Hurd i386.
+
+ Copyright (C) 2024 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program 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 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef I386_GNU_TDEP_H
+#define I386_GNU_TDEP_H
+
+/* Mapping between the general-purpose registers in Hurd i386 thread
+ state and GDB's register cache layout.
+ Indexed by amd64_regnum. */
+extern int i386_gnu_thread_state_reg_offset[];
+extern const int i386_gnu_thread_state_num_regs;
+
+#endif /* I386_GNU_TDEP_H */
diff --git a/gdb/i386-gnu-nat.c b/gdb/x86-gnu-nat.c
similarity index 75%
rename from gdb/i386-gnu-nat.c
rename to gdb/x86-gnu-nat.c
index 0b0759179aa..9a28c5e6a11 100644
--- a/gdb/i386-gnu-nat.c
+++ b/gdb/x86-gnu-nat.c
@@ -35,29 +35,41 @@ extern "C"
#include "floatformat.h"
#include "regcache.h"

+#ifdef __x86_64__
+#include "amd64-tdep.h"
+#include "amd64-nat.h"
+#include "amd64-gnu-tdep.h"
+#else
#include "i386-tdep.h"
+#include "i386-gnu-tdep.h"
+#endif

#include "inf-child.h"
#include "i387-tdep.h"

-/* Offset to the thread_state_t location where REG is stored. */
-#define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
+#ifdef __x86_64__

-/* At REG_OFFSET[N] is the offset to the thread_state_t location where
- the GDB register N is stored. */
-static int reg_offset[] =
-{
- REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
- REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
- REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
- REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
-};
+#define REG_ADDR(state, regnum) \
+ ((char *)(state) + amd64_gnu_thread_state_reg_offset[regnum])
+#define VALID_REGISTER(regnum) \
+ ((regnum) >= 0 && (regnum) < amd64_gnu_thread_state_num_regs)
+#define NUM_GREGS amd64_gnu_thread_state_num_regs
+#define FLAGS_REGISTER rfl

-#define REG_ADDR(state, regnum) ((char *)(state) + reg_offset[regnum])
+#else
+
+#define REG_ADDR(state, regnum) \
+ ((char *)(state) + i386_gnu_thread_state_reg_offset[regnum])
+#define VALID_REGISTER(regnum) \
+ ((regnum) >= 0 && (regnum) < i386_gnu_thread_state_num_regs)
+#define NUM_GREGS i386_gnu_thread_state_num_regs
+#define FLAGS_REGISTER efl
+
+#endif /* __x86_64__ */

\f

-/* The i386 GNU Hurd target. */
+/* The x86 GNU Hurd target. */

#ifdef i386_DEBUG_STATE
using gnu_base_target = x86_nat_target<gnu_nat_target>;
@@ -65,13 +77,13 @@ using gnu_base_target = x86_nat_target<gnu_nat_target>;
using gnu_base_target = gnu_nat_target;
#endif

-struct i386_gnu_nat_target final : public gnu_base_target
+struct x86_gnu_nat_target final : public gnu_base_target
{
void fetch_registers (struct regcache *, int) override;
void store_registers (struct regcache *, int) override;
};

-static i386_gnu_nat_target the_i386_gnu_nat_target;
+static x86_gnu_nat_target the_x86_gnu_nat_target;

/* Get the whole floating-point state of THREAD and record the values
of the corresponding (pseudo) registers. */
@@ -106,7 +118,7 @@ fetch_fpregs (struct regcache *regcache, struct proc *thread)

/* Fetch register REGNO, or all regs if REGNO is -1. */
void
-i386_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno)
+x86_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno)
{
struct proc *thread;
ptid_t ptid = regcache->ptid ();
@@ -119,7 +131,7 @@ i386_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno)
error (_("Can't fetch registers from thread %s: No such thread"),
target_pid_to_str (ptid).c_str ());

- if (regno < I386_NUM_GREGS || regno == -1)
+ if (VALID_REGISTER (regno) || regno == -1)
{
thread_state_t state;

@@ -138,7 +150,7 @@ i386_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno)

proc_debug (thread, "fetching all register");

- for (i = 0; i < I386_NUM_GREGS; i++)
+ for (i = 0; i < NUM_GREGS; i++)
regcache->raw_supply (i, REG_ADDR (state, i));
thread->fetched_regs = ~0;
}
@@ -153,7 +165,7 @@ i386_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno)
}
}

- if (regno >= I386_NUM_GREGS || regno == -1)
+ if (!VALID_REGISTER(regno) || regno == -1)
{
proc_debug (thread, "fetching floating-point registers");

@@ -196,7 +208,7 @@ store_fpregs (const struct regcache *regcache, struct proc *thread, int regno)

/* Store at least register REGNO, or all regs if REGNO == -1. */
void
-i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)
+x86_gnu_nat_target::store_registers (struct regcache *regcache, int regno)
{
struct proc *thread;
struct gdbarch *gdbarch = regcache->arch ();
@@ -210,7 +222,7 @@ i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)
error (_("Couldn't store registers into thread %s: No such thread"),
target_pid_to_str (ptid).c_str ());

- if (regno < I386_NUM_GREGS || regno == -1)
+ if (VALID_REGISTER (regno) || regno == -1)
{
thread_state_t state;
thread_state_data_t old_state;
@@ -231,14 +243,14 @@ i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)

/* Save the T bit. We might try to restore the %eflags register
below, but changing the T bit would seriously confuse GDB. */
- trace = ((struct i386_thread_state *)state)->efl & 0x100;
+ trace = ((struct i386_thread_state *)state)->FLAGS_REGISTER & 0x100;

if (!was_aborted && was_valid)
/* See which registers have changed after aborting the thread. */
{
int check_regno;

- for (check_regno = 0; check_regno < I386_NUM_GREGS; check_regno++)
+ for (check_regno = 0; check_regno < NUM_GREGS; check_regno++)
if ((thread->fetched_regs & (1 << check_regno))
&& memcpy (REG_ADDR (&old_state, check_regno),
REG_ADDR (state, check_regno),
@@ -263,7 +275,7 @@ i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)

proc_debug (thread, "storing all registers");

- for (i = 0; i < I386_NUM_GREGS; i++)
+ for (i = 0; i < NUM_GREGS; i++)
if (REG_VALID == regcache->get_register_status (i))
regcache->raw_collect (i, REG_ADDR (state, i));
}
@@ -277,11 +289,11 @@ i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)
}

/* Restore the T bit. */
- ((struct i386_thread_state *)state)->efl &= ~0x100;
- ((struct i386_thread_state *)state)->efl |= trace;
+ ((struct i386_thread_state *)state)->FLAGS_REGISTER &= ~0x100;
+ ((struct i386_thread_state *)state)->FLAGS_REGISTER |= trace;
}

- if (regno >= I386_NUM_GREGS || regno == -1)
+ if (!VALID_REGISTER (regno) || regno == -1)
{
proc_debug (thread, "storing floating-point registers");

@@ -296,7 +308,7 @@ i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno)
/* Get debug registers for thread THREAD. */

static void
-i386_gnu_dr_get (struct i386_debug_state *regs, struct proc *thread)
+x86_gnu_dr_get (struct i386_debug_state *regs, struct proc *thread)
{
mach_msg_type_number_t count = i386_DEBUG_STATE_COUNT;
kern_return_t err;
@@ -311,7 +323,7 @@ i386_gnu_dr_get (struct i386_debug_state *regs, struct proc *thread)
/* Set debug registers for thread THREAD. */

static void
-i386_gnu_dr_set (const struct i386_debug_state *regs, struct proc *thread)
+x86_gnu_dr_set (const struct i386_debug_state *regs, struct proc *thread)
{
kern_return_t err;

@@ -325,23 +337,23 @@ i386_gnu_dr_set (const struct i386_debug_state *regs, struct proc *thread)
/* Set DR_CONTROL in THREAD. */

static void
-i386_gnu_dr_set_control_one (struct proc *thread, void *arg)
+x86_gnu_dr_set_control_one (struct proc *thread, void *arg)
{
unsigned long *control = (unsigned long *) arg;
struct i386_debug_state regs;

- i386_gnu_dr_get (&regs, thread);
+ x86_gnu_dr_get (&regs, thread);
regs.dr[DR_CONTROL] = *control;
- i386_gnu_dr_set (&regs, thread);
+ x86_gnu_dr_set (&regs, thread);
}

/* Set DR_CONTROL to CONTROL in all threads. */

static void
-i386_gnu_dr_set_control (unsigned long control)
+x86_gnu_dr_set_control (unsigned long control)
{
inf_update_procs (gnu_current_inf);
- inf_threads (gnu_current_inf, i386_gnu_dr_set_control_one, &control);
+ inf_threads (gnu_current_inf, x86_gnu_dr_set_control_one, &control);
}

/* Parameters to set a debugging address. */
@@ -355,20 +367,20 @@ struct reg_addr
/* Set address REGNUM (zero based) to ADDR in THREAD. */

static void
-i386_gnu_dr_set_addr_one (struct proc *thread, void *arg)
+x86_gnu_dr_set_addr_one (struct proc *thread, void *arg)
{
struct reg_addr *reg_addr = (struct reg_addr *) arg;
struct i386_debug_state regs;

- i386_gnu_dr_get (&regs, thread);
+ x86_gnu_dr_get (&regs, thread);
regs.dr[reg_addr->regnum] = reg_addr->addr;
- i386_gnu_dr_set (&regs, thread);
+ x86_gnu_dr_set (&regs, thread);
}

/* Set address REGNUM (zero based) to ADDR in all threads. */

static void
-i386_gnu_dr_set_addr (int regnum, CORE_ADDR addr)
+x86_gnu_dr_set_addr (int regnum, CORE_ADDR addr)
{
struct reg_addr reg_addr;

@@ -378,13 +390,13 @@ i386_gnu_dr_set_addr (int regnum, CORE_ADDR addr)
reg_addr.addr = addr;

inf_update_procs (gnu_current_inf);
- inf_threads (gnu_current_inf, i386_gnu_dr_set_addr_one, &reg_addr);
+ inf_threads (gnu_current_inf, x86_gnu_dr_set_addr_one, &reg_addr);
}

/* Get debug register REGNUM value from only the one LWP of PTID. */

static unsigned long
-i386_gnu_dr_get_reg (ptid_t ptid, int regnum)
+x86_gnu_dr_get_reg (ptid_t ptid, int regnum)
{
struct i386_debug_state regs;
struct proc *thread;
@@ -393,7 +405,7 @@ i386_gnu_dr_get_reg (ptid_t ptid, int regnum)
inf_update_procs (gnu_current_inf);

thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ());
- i386_gnu_dr_get (&regs, thread);
+ x86_gnu_dr_get (&regs, thread);

return regs.dr[regnum];
}
@@ -401,46 +413,50 @@ i386_gnu_dr_get_reg (ptid_t ptid, int regnum)
/* Return the inferior's debug register REGNUM. */

static CORE_ADDR
-i386_gnu_dr_get_addr (int regnum)
+x86_gnu_dr_get_addr (int regnum)
{
gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);

- return i386_gnu_dr_get_reg (inferior_ptid, regnum);
+ return x86_gnu_dr_get_reg (inferior_ptid, regnum);
}

/* Get DR_STATUS from only the one thread of INFERIOR_PTID. */

static unsigned long
-i386_gnu_dr_get_status (void)
+x86_gnu_dr_get_status (void)
{
- return i386_gnu_dr_get_reg (inferior_ptid, DR_STATUS);
+ return x86_gnu_dr_get_reg (inferior_ptid, DR_STATUS);
}

/* Return the inferior's DR7 debug control register. */

static unsigned long
-i386_gnu_dr_get_control (void)
+x86_gnu_dr_get_control (void)
{
- return i386_gnu_dr_get_reg (inferior_ptid, DR_CONTROL);
+ return x86_gnu_dr_get_reg (inferior_ptid, DR_CONTROL);
}
#endif /* i386_DEBUG_STATE */

-void _initialize_i386gnu_nat ();
+void _initialize_x86_gnu_nat ();
void
-_initialize_i386gnu_nat ()
+_initialize_x86_gnu_nat ()
{
#ifdef i386_DEBUG_STATE
- x86_dr_low.set_control = i386_gnu_dr_set_control;
+ x86_dr_low.set_control = x86_gnu_dr_set_control;
gdb_assert (DR_FIRSTADDR == 0 && DR_LASTADDR < i386_DEBUG_STATE_COUNT);
- x86_dr_low.set_addr = i386_gnu_dr_set_addr;
- x86_dr_low.get_addr = i386_gnu_dr_get_addr;
- x86_dr_low.get_status = i386_gnu_dr_get_status;
- x86_dr_low.get_control = i386_gnu_dr_get_control;
+ x86_dr_low.set_addr = x86_gnu_dr_set_addr;
+ x86_dr_low.get_addr = x86_gnu_dr_get_addr;
+ x86_dr_low.get_status = x86_gnu_dr_get_status;
+ x86_dr_low.get_control = x86_gnu_dr_get_control;
+#ifdef __x86_64__
+ x86_set_debug_register_length (8);
+#else
x86_set_debug_register_length (4);
+#endif
#endif /* i386_DEBUG_STATE */

- gnu_target = &the_i386_gnu_nat_target;
+ gnu_target = &the_x86_gnu_nat_target;

/* Register the target. */
- add_inf_child_target (&the_i386_gnu_nat_target);
+ add_inf_child_target (&the_x86_gnu_nat_target);
}
--
2.39.2