--- /dev/null
+/* Target-dependent code for FreeBSD/i386.
+
+ Copyright (C) 2003-2016 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 "arch-utils.h"
+#include "gdbcore.h"
+#include "osabi.h"
+#include "regcache.h"
+#include "regset.h"
+#include "i386-fbsd-tdep.h"
+#include "x86-xstate.h"
+
+#include "i386-tdep.h"
+#include "i387-tdep.h"
+#include "bsd-uthread.h"
+#include "fbsd-tdep.h"
+#include "solib-svr4.h"
+
+/* Support for signal handlers. */
+
+/* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp
+ routine. */
+
+/* FreeBSD/i386 supports three different signal trampolines, one for
+ versions before 4.0, a second for 4.x, and a third for 5.0 and
+ later. To complicate matters, FreeBSD/i386 binaries running under
+ an amd64 kernel use a different set of trampolines. These
+ trampolines differ from the i386 kernel trampolines in that they
+ omit a middle section that conditionally restores %gs. */
+
+static const gdb_byte i386fbsd_sigtramp_start[] =
+{
+ 0x8d, 0x44, 0x24, 0x20, /* lea SIGF_UC(%esp),%eax */
+ 0x50 /* pushl %eax */
+};
+
+static const gdb_byte i386fbsd_sigtramp_middle[] =
+{
+ 0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
+ /* testl $PSL_VM,UC_EFLAGS(%eax) */
+ 0x75, 0x03, /* jne +3 */
+ 0x8e, 0x68, 0x14 /* mov UC_GS(%eax),%gs */
+};
+
+static const gdb_byte i386fbsd_sigtramp_end[] =
+{
+ 0xb8, 0xa1, 0x01, 0x00, 0x00, /* movl $SYS_sigreturn,%eax */
+ 0x50, /* pushl %eax */
+ 0xcd, 0x80 /* int $0x80 */
+};
+
+static const gdb_byte i386fbsd_freebsd4_sigtramp_start[] =
+{
+ 0x8d, 0x44, 0x24, 0x14, /* lea SIGF_UC4(%esp),%eax */
+ 0x50 /* pushl %eax */
+};
+
+static const gdb_byte i386fbsd_freebsd4_sigtramp_middle[] =
+{
+ 0xf7, 0x40, 0x54, 0x00, 0x00, 0x02, 0x00,
+ /* testl $PSL_VM,UC4_EFLAGS(%eax) */
+ 0x75, 0x03, /* jne +3 */
+ 0x8e, 0x68, 0x14 /* mov UC4_GS(%eax),%gs */
+};
+
+static const gdb_byte i386fbsd_freebsd4_sigtramp_end[] =
+{
+ 0xb8, 0x58, 0x01, 0x00, 0x00, /* movl $344,%eax */
+ 0x50, /* pushl %eax */
+ 0xcd, 0x80 /* int $0x80 */
+};
+
+static const gdb_byte i386fbsd_osigtramp_start[] =
+{
+ 0x8d, 0x44, 0x24, 0x14, /* lea SIGF_SC(%esp),%eax */
+ 0x50 /* pushl %eax */
+};
+
+static const gdb_byte i386fbsd_osigtramp_middle[] =
+{
+ 0xf7, 0x40, 0x18, 0x00, 0x00, 0x02, 0x00,
+ /* testl $PSL_VM,SC_PS(%eax) */
+ 0x75, 0x03, /* jne +3 */
+ 0x8e, 0x68, 0x44 /* mov SC_GS(%eax),%gs */
+};
+
+static const gdb_byte i386fbsd_osigtramp_end[] =
+{
+ 0xb8, 0x67, 0x00, 0x00, 0x00, /* movl $103,%eax */
+ 0x50, /* pushl %eax */
+ 0xcd, 0x80 /* int $0x80 */
+};
+
+/* The three different trampolines are all the same size. */
+gdb_static_assert (sizeof i386fbsd_sigtramp_start
+ == sizeof i386fbsd_freebsd4_sigtramp_start);
+gdb_static_assert (sizeof i386fbsd_sigtramp_start
+ == sizeof i386fbsd_osigtramp_start);
+gdb_static_assert (sizeof i386fbsd_sigtramp_middle
+ == sizeof i386fbsd_freebsd4_sigtramp_middle);
+gdb_static_assert (sizeof i386fbsd_sigtramp_middle
+ == sizeof i386fbsd_osigtramp_middle);
+gdb_static_assert (sizeof i386fbsd_sigtramp_end
+ == sizeof i386fbsd_freebsd4_sigtramp_end);
+gdb_static_assert (sizeof i386fbsd_sigtramp_end
+ == sizeof i386fbsd_osigtramp_end);
+
+/* We assume that the middle is the largest chunk below. */
+gdb_static_assert (sizeof i386fbsd_sigtramp_middle
+ > sizeof i386fbsd_sigtramp_start);
+gdb_static_assert (sizeof i386fbsd_sigtramp_middle
+ > sizeof i386fbsd_sigtramp_end);
+
+static int
+i386fbsd_sigtramp_p (struct frame_info *this_frame)
+{
+ CORE_ADDR pc = get_frame_pc (this_frame);
+ gdb_byte buf[sizeof i386fbsd_sigtramp_middle];
+ const gdb_byte *middle, *end;
+
+ /* Look for a matching start. */
+ if (!safe_frame_unwind_memory (this_frame, pc, buf,
+ sizeof i386fbsd_sigtramp_start))
+ return 0;
+ if (memcmp (buf, i386fbsd_sigtramp_start, sizeof i386fbsd_sigtramp_start)
+ == 0)
+ {
+ middle = i386fbsd_sigtramp_middle;
+ end = i386fbsd_sigtramp_end;
+ }
+ else if (memcmp (buf, i386fbsd_freebsd4_sigtramp_start,
+ sizeof i386fbsd_freebsd4_sigtramp_start) == 0)
+ {
+ middle = i386fbsd_freebsd4_sigtramp_middle;
+ end = i386fbsd_freebsd4_sigtramp_end;
+ }
+ else if (memcmp (buf, i386fbsd_osigtramp_start,
+ sizeof i386fbsd_osigtramp_start) == 0)
+ {
+ middle = i386fbsd_osigtramp_middle;
+ end = i386fbsd_osigtramp_end;
+ }
+ else
+ return 0;
+
+ /* Since the end is shorter than the middle, check for a matching end
+ next. */
+ pc += sizeof i386fbsd_sigtramp_start;
+ if (!safe_frame_unwind_memory (this_frame, pc, buf,
+ sizeof i386fbsd_sigtramp_end))
+ return 0;
+ if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) == 0)
+ return 1;
+
+ /* If the end didn't match, check for a matching middle. */
+ if (!safe_frame_unwind_memory (this_frame, pc, buf,
+ sizeof i386fbsd_sigtramp_middle))
+ return 0;
+ if (memcmp (buf, middle, sizeof i386fbsd_sigtramp_middle) != 0)
+ return 0;
+
+ /* The middle matched, check for a matching end. */
+ pc += sizeof i386fbsd_sigtramp_middle;
+ if (!safe_frame_unwind_memory (this_frame, pc, buf,
+ sizeof i386fbsd_sigtramp_end))
+ return 0;
+ if (memcmp (buf, end, sizeof i386fbsd_sigtramp_end) != 0)
+ return 0;
+
+ return 1;
+}
+
+/* FreeBSD 3.0-RELEASE or later. */
+
+/* From <machine/reg.h>. */
+static int i386fbsd_r_reg_offset[] =
+{
+ 9 * 4, 8 * 4, 7 * 4, 6 * 4, /* %eax, %ecx, %edx, %ebx */
+ 15 * 4, 4 * 4, /* %esp, %ebp */
+ 3 * 4, 2 * 4, /* %esi, %edi */
+ 12 * 4, 14 * 4, /* %eip, %eflags */
+ 13 * 4, 16 * 4, /* %cs, %ss */
+ 1 * 4, 0 * 4, -1, -1 /* %ds, %es, %fs, %gs */
+};
+
+/* Sigtramp routine location. */
+CORE_ADDR i386fbsd_sigtramp_start_addr;
+CORE_ADDR i386fbsd_sigtramp_end_addr;
+
+/* From <machine/signal.h>. */
+int i386fbsd_sc_reg_offset[] =
+{
+ 8 + 14 * 4, /* %eax */
+ 8 + 13 * 4, /* %ecx */
+ 8 + 12 * 4, /* %edx */
+ 8 + 11 * 4, /* %ebx */
+ 8 + 0 * 4, /* %esp */
+ 8 + 1 * 4, /* %ebp */
+ 8 + 10 * 4, /* %esi */
+ 8 + 9 * 4, /* %edi */
+ 8 + 3 * 4, /* %eip */
+ 8 + 4 * 4, /* %eflags */
+ 8 + 7 * 4, /* %cs */
+ 8 + 8 * 4, /* %ss */
+ 8 + 6 * 4, /* %ds */
+ 8 + 5 * 4, /* %es */
+ 8 + 15 * 4, /* %fs */
+ 8 + 16 * 4 /* %gs */
+};
+
+/* From /usr/src/lib/libc/i386/gen/_setjmp.S. */
+static int i386fbsd_jmp_buf_reg_offset[] =
+{
+ -1, /* %eax */
+ -1, /* %ecx */
+ -1, /* %edx */
+ 1 * 4, /* %ebx */
+ 2 * 4, /* %esp */
+ 3 * 4, /* %ebp */
+ 4 * 4, /* %esi */
+ 5 * 4, /* %edi */
+ 0 * 4 /* %eip */
+};
+
+/* Get XSAVE extended state xcr0 from core dump. */
+
+uint64_t
+i386fbsd_core_read_xcr0 (bfd *abfd)
+{
+ asection *xstate = bfd_get_section_by_name (abfd, ".reg-xstate");
+ uint64_t xcr0;
+
+ if (xstate)
+ {
+ size_t size = bfd_section_size (abfd, xstate);
+
+ /* Check extended state size. */
+ if (size < X86_XSTATE_AVX_SIZE)
+ xcr0 = X86_XSTATE_SSE_MASK;
+ else
+ {
+ char contents[8];
+
+ if (! bfd_get_section_contents (abfd, xstate, contents,
+ I386_FBSD_XSAVE_XCR0_OFFSET,
+ 8))
+ {
+ warning (_("Couldn't read `xcr0' bytes from "
+ "`.reg-xstate' section in core file."));
+ return 0;
+ }
+
+ xcr0 = bfd_get_64 (abfd, contents);
+ }
+ }
+ else
+ xcr0 = 0;
+
+ return xcr0;
+}
+
+/* Implement the core_read_description gdbarch method. */
+
+static const struct target_desc *
+i386fbsd_core_read_description (struct gdbarch *gdbarch,
+ struct target_ops *target,
+ bfd *abfd)
+{
+ return i386_target_description (i386fbsd_core_read_xcr0 (abfd));
+}
+
+/* Similar to i386_supply_fpregset, but use XSAVE extended state. */
+
+static void
+i386fbsd_supply_xstateregset (const struct regset *regset,
+ struct regcache *regcache, int regnum,
+ const void *xstateregs, size_t len)
+{
+ i387_supply_xsave (regcache, regnum, xstateregs);
+}
+
+/* Similar to i386_collect_fpregset, but use XSAVE extended state. */
+
+static void
+i386fbsd_collect_xstateregset (const struct regset *regset,
+ const struct regcache *regcache,
+ int regnum, void *xstateregs, size_t len)
+{
+ i387_collect_xsave (regcache, regnum, xstateregs, 1);
+}
+
+/* Register set definitions. */
+
+static const struct regset i386fbsd_xstateregset =
+ {
+ NULL,
+ i386fbsd_supply_xstateregset,
+ i386fbsd_collect_xstateregset
+ };
+
+/* Iterate over core file register note sections. */
+
+static void
+i386fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
+ iterate_over_regset_sections_cb *cb,
+ void *cb_data,
+ const struct regcache *regcache)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ cb (".reg", tdep->sizeof_gregset, &i386_gregset, NULL, cb_data);
+ cb (".reg2", tdep->sizeof_fpregset, &i386_fpregset, NULL, cb_data);
+
+ if (tdep->xcr0 & X86_XSTATE_AVX)
+ cb (".reg-xstate", X86_XSTATE_SIZE(tdep->xcr0),
+ &i386fbsd_xstateregset, "XSAVE extended state", cb_data);
+}
+
+static void
+i386fbsd_supply_uthread (struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ gdb_byte buf[4];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
+ {
+ if (i386fbsd_jmp_buf_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ read_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
+ regcache_raw_supply (regcache, i, buf);
+ }
+ }
+}
+
+static void
+i386fbsd_collect_uthread (const struct regcache *regcache,
+ int regnum, CORE_ADDR addr)
+{
+ gdb_byte buf[4];
+ int i;
+
+ gdb_assert (regnum >= -1);
+
+ for (i = 0; i < ARRAY_SIZE (i386fbsd_jmp_buf_reg_offset); i++)
+ {
+ if (i386fbsd_jmp_buf_reg_offset[i] != -1
+ && (regnum == -1 || regnum == i))
+ {
+ regcache_raw_collect (regcache, i, buf);
+ write_memory (addr + i386fbsd_jmp_buf_reg_offset[i], buf, 4);
+ }
+ }
+}
+
+static void
+i386fbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* Obviously FreeBSD is BSD-based. */
+ i386bsd_init_abi (info, gdbarch);
+
+ /* FreeBSD has a different `struct reg', and reserves some space for
+ its FPU emulator in `struct fpreg'. */
+ tdep->gregset_reg_offset = i386fbsd_r_reg_offset;
+ tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd_r_reg_offset);
+ tdep->sizeof_gregset = 18 * 4;
+ tdep->sizeof_fpregset = 176;
+
+ /* FreeBSD uses -freg-struct-return by default. */
+ tdep->struct_return = reg_struct_return;
+
+ tdep->sigtramp_p = i386fbsd_sigtramp_p;
+
+ /* FreeBSD uses a different memory layout. */
+ tdep->sigtramp_start = i386fbsd_sigtramp_start_addr;
+ tdep->sigtramp_end = i386fbsd_sigtramp_end_addr;
+
+ /* FreeBSD has a more complete `struct sigcontext'. */
+ tdep->sc_reg_offset = i386fbsd_sc_reg_offset;
+ tdep->sc_num_regs = ARRAY_SIZE (i386fbsd_sc_reg_offset);
+
+ /* FreeBSD provides a user-level threads implementation. */
+ bsd_uthread_set_supply_uthread (gdbarch, i386fbsd_supply_uthread);
+ bsd_uthread_set_collect_uthread (gdbarch, i386fbsd_collect_uthread);
+}
+
+static void
+i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ /* It's almost identical to FreeBSD a.out. */
+ i386fbsdaout_init_abi (info, gdbarch);
+
+ /* Except that it uses ELF. */
+ i386_elf_init_abi (info, gdbarch);
+
+ /* FreeBSD ELF uses SVR4-style shared libraries. */
+ set_solib_svr4_fetch_link_map_offsets
+ (gdbarch, svr4_ilp32_fetch_link_map_offsets);
+}
+
+/* FreeBSD 4.0-RELEASE or later. */
+
+/* From <machine/reg.h>. */
+static int i386fbsd4_r_reg_offset[] =
+{
+ 10 * 4, 9 * 4, 8 * 4, 7 * 4, /* %eax, %ecx, %edx, %ebx */
+ 16 * 4, 5 * 4, /* %esp, %ebp */
+ 4 * 4, 3 * 4, /* %esi, %edi */
+ 13 * 4, 15 * 4, /* %eip, %eflags */
+ 14 * 4, 17 * 4, /* %cs, %ss */
+ 2 * 4, 1 * 4, 0 * 4, 18 * 4 /* %ds, %es, %fs, %gs */
+};
+
+/* From <machine/signal.h>. */
+int i386fbsd4_sc_reg_offset[] =
+{
+ 20 + 11 * 4, /* %eax */
+ 20 + 10 * 4, /* %ecx */
+ 20 + 9 * 4, /* %edx */
+ 20 + 8 * 4, /* %ebx */
+ 20 + 17 * 4, /* %esp */
+ 20 + 6 * 4, /* %ebp */
+ 20 + 5 * 4, /* %esi */
+ 20 + 4 * 4, /* %edi */
+ 20 + 14 * 4, /* %eip */
+ 20 + 16 * 4, /* %eflags */
+ 20 + 15 * 4, /* %cs */
+ 20 + 18 * 4, /* %ss */
+ 20 + 3 * 4, /* %ds */
+ 20 + 2 * 4, /* %es */
+ 20 + 1 * 4, /* %fs */
+ 20 + 0 * 4 /* %gs */
+};
+
+static void
+i386fbsd4_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* Generic FreeBSD support. */
+ fbsd_init_abi (info, gdbarch);
+
+ /* Inherit stuff from older releases. We assume that FreeBSD
+ 4.0-RELEASE always uses ELF. */
+ i386fbsd_init_abi (info, gdbarch);
+
+ /* FreeBSD 4.0 introduced a new `struct reg'. */
+ tdep->gregset_reg_offset = i386fbsd4_r_reg_offset;
+ tdep->gregset_num_regs = ARRAY_SIZE (i386fbsd4_r_reg_offset);
+ tdep->sizeof_gregset = 19 * 4;
+
+ /* FreeBSD 4.0 introduced a new `struct sigcontext'. */
+ tdep->sc_reg_offset = i386fbsd4_sc_reg_offset;
+ tdep->sc_num_regs = ARRAY_SIZE (i386fbsd4_sc_reg_offset);
+
+ tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET;
+
+ /* Iterate over core file register note sections. */
+ set_gdbarch_iterate_over_regset_sections
+ (gdbarch, i386fbsd_iterate_over_regset_sections);
+
+ set_gdbarch_core_read_description (gdbarch,
+ i386fbsd_core_read_description);
+}
+
+\f
+/* Provide a prototype to silence -Wmissing-prototypes. */
+void _initialize_i386fbsd_tdep (void);
+
+void
+_initialize_i386fbsd_tdep (void)
+{
+ gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_AOUT,
+ i386fbsdaout_init_abi);
+ gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_FREEBSD_ELF,
+ i386fbsd4_init_abi);
+}
projects / deliverable / binutils-gdb.git / blobdiff