From 22ca5c10279903a221ba4580afef71af0c639704 Mon Sep 17 00:00:00 2001 From: John Baldwin Date: Mon, 28 Aug 2023 14:18:19 -0700 Subject: [PATCH] gdb: Update x86 FreeBSD architectures to support XSAVE layouts. Refactor i386fbsd_core_read_xcr0 to fetch and return a corresponding x86_xsave_layout as well as xcr0 using the size of an existing NT_X86_XSTATE core dump to determine the offsets via i387_guess_xsave_layout. Use this to add an implementation of gdbarch_core_xfer_x86_xsave_layout. Use tdep->xsave_layout.sizeof_xsave as the size of the XSTATE register set and only fetch/store the register set if this size is non-zero. Approved-By: Simon Marchi --- gdb/amd64-fbsd-tdep.c | 15 +++++++-- gdb/i386-fbsd-tdep.c | 71 ++++++++++++++++++++++++------------------- gdb/i386-fbsd-tdep.h | 14 +++++++-- 3 files changed, 64 insertions(+), 36 deletions(-) diff --git a/gdb/amd64-fbsd-tdep.c b/gdb/amd64-fbsd-tdep.c index 0d5ce004fb1..2b633cd479c 100644 --- a/gdb/amd64-fbsd-tdep.c +++ b/gdb/amd64-fbsd-tdep.c @@ -224,7 +224,12 @@ amd64fbsd_core_read_description (struct gdbarch *gdbarch, struct target_ops *target, bfd *abfd) { - return amd64_target_description (i386fbsd_core_read_xcr0 (abfd), true); + x86_xsave_layout layout; + uint64_t xcr0 = i386_fbsd_core_read_xsave_info (abfd, layout); + if (xcr0 == 0) + xcr0 = X86_XSTATE_SSE_MASK; + + return amd64_target_description (xcr0, true); } /* Similar to amd64_supply_fpregset, but use XSAVE extended state. */ @@ -271,8 +276,10 @@ amd64fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, cb (".reg-x86-segbases", AMD64_FBSD_SIZEOF_SEGBASES_REGSET, AMD64_FBSD_SIZEOF_SEGBASES_REGSET, &amd64_fbsd_segbases_regset, "segment bases", cb_data); - cb (".reg-xstate", X86_XSTATE_SIZE (tdep->xcr0), X86_XSTATE_SIZE (tdep->xcr0), - &amd64fbsd_xstateregset, "XSAVE extended state", cb_data); + if (tdep->xsave_layout.sizeof_xsave != 0) + cb (".reg-xstate", tdep->xsave_layout.sizeof_xsave, + tdep->xsave_layout.sizeof_xsave, &amd64fbsd_xstateregset, + "XSAVE extended state", cb_data); } /* Implement the get_thread_local_address gdbarch method. */ @@ -313,6 +320,8 @@ amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) tramp_frame_prepend_unwinder (gdbarch, &amd64_fbsd_sigframe); tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET; + set_gdbarch_core_read_x86_xsave_layout + (gdbarch, i386_fbsd_core_read_x86_xsave_layout); /* Iterate over core file register note sections. */ set_gdbarch_iterate_over_regset_sections diff --git a/gdb/i386-fbsd-tdep.c b/gdb/i386-fbsd-tdep.c index fb9030413ab..f8c2758c2b0 100644 --- a/gdb/i386-fbsd-tdep.c +++ b/gdb/i386-fbsd-tdep.c @@ -18,13 +18,13 @@ along with this program. If not, see . */ #include "defs.h" +#include "gdbcore.h" #include "osabi.h" #include "regcache.h" #include "regset.h" #include "trad-frame.h" #include "tramp-frame.h" #include "i386-fbsd-tdep.h" -#include "gdbsupport/x86-xstate.h" #include "i386-tdep.h" #include "i387-tdep.h" @@ -241,43 +241,46 @@ static const struct tramp_frame i386_fbsd64_sigframe = i386_fbsd_sigframe_init }; -/* Get XSAVE extended state xcr0 from core dump. */ +/* See i386-fbsd-tdep.h. */ uint64_t -i386fbsd_core_read_xcr0 (bfd *abfd) +i386_fbsd_core_read_xsave_info (bfd *abfd, x86_xsave_layout &layout) { asection *xstate = bfd_get_section_by_name (abfd, ".reg-xstate"); - uint64_t xcr0; + if (xstate == nullptr) + return 0; - if (xstate) + /* Check extended state size. */ + size_t size = bfd_section_size (xstate); + if (size < X86_XSTATE_AVX_SIZE) + return 0; + + char contents[8]; + if (! bfd_get_section_contents (abfd, xstate, contents, + I386_FBSD_XSAVE_XCR0_OFFSET, 8)) { - size_t size = bfd_section_size (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 X86_XSTATE_SSE_MASK; - } - - xcr0 = bfd_get_64 (abfd, contents); - } + warning (_("Couldn't read `xcr0' bytes from " + "`.reg-xstate' section in core file.")); + return 0; } - else - xcr0 = X86_XSTATE_SSE_MASK; + + uint64_t xcr0 = bfd_get_64 (abfd, contents); + + if (!i387_guess_xsave_layout (xcr0, size, layout)) + return 0; return xcr0; } +/* See i386-fbsd-tdep.h. */ + +bool +i386_fbsd_core_read_x86_xsave_layout (struct gdbarch *gdbarch, + x86_xsave_layout &layout) +{ + return i386_fbsd_core_read_xsave_info (core_bfd, layout) != 0; +} + /* Implement the core_read_description gdbarch method. */ static const struct target_desc * @@ -285,7 +288,11 @@ i386fbsd_core_read_description (struct gdbarch *gdbarch, struct target_ops *target, bfd *abfd) { - return i386_target_description (i386fbsd_core_read_xcr0 (abfd), true); + x86_xsave_layout layout; + uint64_t xcr0 = i386_fbsd_core_read_xsave_info (abfd, layout); + if (xcr0 == 0) + xcr0 = X86_XSTATE_X87_MASK; + return i386_target_description (xcr0, true); } /* Similar to i386_supply_fpregset, but use XSAVE extended state. */ @@ -335,9 +342,9 @@ i386fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, I386_FBSD_SIZEOF_SEGBASES_REGSET, &i386_fbsd_segbases_regset, "segment bases", cb_data); - if (tdep->xcr0 & X86_XSTATE_AVX) - cb (".reg-xstate", X86_XSTATE_SIZE (tdep->xcr0), - X86_XSTATE_SIZE (tdep->xcr0), &i386fbsd_xstateregset, + if (tdep->xsave_layout.sizeof_xsave != 0) + cb (".reg-xstate", tdep->xsave_layout.sizeof_xsave, + tdep->xsave_layout.sizeof_xsave, &i386fbsd_xstateregset, "XSAVE extended state", cb_data); } @@ -386,6 +393,8 @@ i386fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) i386_elf_init_abi (info, gdbarch); tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET; + set_gdbarch_core_read_x86_xsave_layout + (gdbarch, i386_fbsd_core_read_x86_xsave_layout); /* Iterate over core file register note sections. */ set_gdbarch_iterate_over_regset_sections diff --git a/gdb/i386-fbsd-tdep.h b/gdb/i386-fbsd-tdep.h index cb991af9e49..c49cb1eba68 100644 --- a/gdb/i386-fbsd-tdep.h +++ b/gdb/i386-fbsd-tdep.h @@ -20,10 +20,20 @@ #ifndef I386_FBSD_TDEP_H #define I386_FBSD_TDEP_H +#include "gdbsupport/x86-xstate.h" #include "regset.h" -/* Get XSAVE extended state xcr0 from core dump. */ -extern uint64_t i386fbsd_core_read_xcr0 (bfd *abfd); +/* Read the XSAVE extended state xcr0 value from the ABFD core file. + If it appears to be valid, return it and fill LAYOUT with values + inferred from that value. + + Otherwise, return 0 to indicate no state was found and leave LAYOUT + untouched. */ +uint64_t i386_fbsd_core_read_xsave_info (bfd *abfd, x86_xsave_layout &layout); + +/* Implement the core_read_x86_xsave_layout gdbarch method. */ +bool i386_fbsd_core_read_x86_xsave_layout (struct gdbarch *gdbarch, + x86_xsave_layout &layout); /* The format of the XSAVE extended area is determined by hardware. Cores store the XSAVE extended area in a NT_X86_XSTATE note that -- 2.30.2