binutils-gdb/gdb/x86-tdep.c

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infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
2018-02-14 21:30:57 +08:00
/* Target-dependent code for X86-based targets.
Copyright (C) 2018-2022 Free Software Foundation, Inc.
infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
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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 "x86-tdep.h"
Don't include gdbarch.h from defs.h I touched symtab.h and was surprised to see how many files were rebuilt. I looked into it a bit, and found that defs.h includes gdbarch.h, which in turn includes many things. gdbarch.h is only needed by a minority ofthe files in gdb, so this patch removes the include from defs.h and updates the fallout. I did "wc -l" on the files in build/gdb/.deps; this patch reduces the line count from 139935 to 137030; so there are definitely future build-time savings here. Note that while I configured with --enable-targets=all, it's possible that some *-nat.c file needs an update. I could not test all of these. The buildbot caught a few problems along these lines. gdb/ChangeLog 2019-07-10 Tom Tromey <tom@tromey.com> * defs.h: Don't include gdbarch.h. * aarch64-ravenscar-thread.c, aarch64-tdep.c, alpha-bsd-tdep.h, alpha-linux-tdep.c, alpha-mdebug-tdep.c, arch-utils.h, arm-tdep.h, ax-general.c, btrace.c, buildsym-legacy.c, buildsym.h, c-lang.c, cli/cli-decode.h, cli/cli-dump.c, cli/cli-script.h, cli/cli-style.h, coff-pe-read.h, compile/compile-c-support.c, compile/compile-cplus.h, compile/compile-loc2c.c, corefile.c, cp-valprint.c, cris-linux-tdep.c, ctf.c, d-lang.c, d-namespace.c, dcache.c, dicos-tdep.c, dictionary.c, disasm-selftests.c, dummy-frame.c, dummy-frame.h, dwarf2-frame-tailcall.c, dwarf2expr.c, expression.h, f-lang.c, frame-base.c, frame-unwind.c, frv-linux-tdep.c, gdbarch-selftests.c, gdbtypes.h, go-lang.c, hppa-nbsd-tdep.c, hppa-obsd-tdep.c, i386-dicos-tdep.c, i386-tdep.h, ia64-vms-tdep.c, interps.h, language.c, linux-record.c, location.h, m2-lang.c, m32r-linux-tdep.c, mem-break.c, memattr.c, mn10300-linux-tdep.c, nios2-linux-tdep.c, objfiles.h, opencl-lang.c, or1k-linux-tdep.c, p-lang.c, parser-defs.h, ppc-tdep.h, probe.h, python/py-record-btrace.c, record-btrace.c, record.h, regcache-dump.c, regcache.h, riscv-fbsd-tdep.c, riscv-linux-tdep.c, rust-exp.y, sh-linux-tdep.c, sh-nbsd-tdep.c, source-cache.c, sparc-nbsd-tdep.c, sparc-obsd-tdep.c, sparc-ravenscar-thread.c, sparc64-fbsd-tdep.c, std-regs.c, target-descriptions.h, target-float.c, tic6x-linux-tdep.c, tilegx-linux-tdep.c, top.c, tracefile.c, trad-frame.c, type-stack.h, ui-style.c, utils.c, utils.h, valarith.c, valprint.c, varobj.c, x86-tdep.c, xml-support.h, xtensa-linux-tdep.c, cli/cli-cmds.h: Update. * s390-linux-nat.c, procfs.c, inf-ptrace.c: Likewise.
2019-06-10 05:21:02 +08:00
#include "symtab.h"
infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
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/* Check whether NAME is included in NAMES[LO] (inclusive) to NAMES[HI]
(exclusive). */
static bool
Apply 'const' in more places Many global arrays in gdb could be marked "const" but are not. This patch changes some of them. (There may be other arrays that could benefit from this treatment. I only examined arrays of strings.) This lets the linker move some symbols to the readonly data section. For example, previously: 0000000000000000 d _ZL18can_use_agent_enum is now: 0000000000000030 r _ZL18can_use_agent_enum 2020-09-14 Tom Tromey <tromey@adacore.com> * x86-tdep.h (x86_in_indirect_branch_thunk): Update. * x86-tdep.c (x86_is_thunk_register_name) (x86_in_indirect_branch_thunk): Update. * sparc64-tdep.c (sparc64_fpu_register_names) (sparc64_cp0_register_names, sparc64_register_names) (sparc64_pseudo_register_names): Now const. * sparc-tdep.h (struct gdbarch_tdep) <fpu_register_names, cp0_registers_num>: Now const. * sparc-tdep.c (sparc_core_register_names) (sparc32_fpu_register_names, sparc32_cp0_register_names) (sparc32_pseudo_register_names): Now const. (validate_tdesc_registers): Update. * rust-lang.c (rust_extensions): Now const. * p-lang.c (p_extensions): Now const. * objc-lang.c (objc_extensions): Now const. * nto-tdep.c (nto_thread_state_str): Now const. * moxie-tdep.c (moxie_register_names): Now const. * mips-tdep.h (struct gdbarch_tdep) <mips_processor_reg_names>: Now const. * mips-tdep.c (mips_generic_reg_names, mips_tx39_reg_names) (mips_linux_reg_names): Now const. (mips_gdbarch_init): Update. * microblaze-tdep.c (microblaze_register_names): Now const. * m68k-tdep.c (m68k_register_names): Now const. * m32r-tdep.c (m32r_register_names): Now const. * ia64-tdep.c (ia64_register_names): Now const. * i386-tdep.h (struct gdbarch_tdep) <register_names, ymmh_register_names, ymm16h_regnum, mpx_register_names, k_register_names, zmmh_register_names, xmm_avx512_register_names, ymm_avx512_register_names, pkeys_register_names>: Now const. * i386-tdep.c (i386_register_names, i386_zmm_names) (i386_zmmh_names, i386_k_names, i386_ymm_names, i386_ymmh_names) (i386_mpx_names, i386_pkeys_names, i386_bnd_names) (i386_mmx_names, i386_byte_names, i386_word_names): Now const. * f-lang.c (f_extensions): Now const. * d-lang.c (d_extensions): Now const. * csky-tdep.c (csky_register_names): Now const. * charset.c (default_charset_names, charset_enum): Now const. (_initialize_charset): Update. * c-lang.c (c_extensions, cplus_extensions, asm_extensions): Now const. * bsd-uthread.c (bsd_uthread_solib_names): Now const. (bsd_uthread_solib_loaded): Update. (bsd_uthread_state): Now const. * amd64-tdep.c (amd64_register_names, amd64_ymm_names) (amd64_ymm_avx512_names, amd64_ymmh_names) (amd64_ymmh_avx512_names, amd64_mpx_names, amd64_k_names) (amd64_zmmh_names, amd64_zmm_names, amd64_xmm_avx512_names) (amd64_pkeys_names, amd64_byte_names, amd64_word_names) (amd64_dword_names): Now const. * agent.c (can_use_agent_enum): Now const. * ada-tasks.c (task_states, long_task_states): Now const. * ada-lang.c (known_runtime_file_name_patterns) (known_auxiliary_function_name_patterns, attribute_names) (standard_exc, ada_extensions): Now const. gdbserver/ChangeLog 2020-09-14 Tom Tromey <tromey@adacore.com> * tracepoint.cc (eval_result_names): Now const. * ax.cc (gdb_agent_op_names): Now const.
2020-09-15 02:09:59 +08:00
x86_is_thunk_register_name (const char *name, const char * const *names,
int lo, int hi)
infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
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{
int reg;
for (reg = lo; reg < hi; ++reg)
if (strcmp (name, names[reg]) == 0)
return true;
return false;
}
/* See x86-tdep.h. */
bool
Apply 'const' in more places Many global arrays in gdb could be marked "const" but are not. This patch changes some of them. (There may be other arrays that could benefit from this treatment. I only examined arrays of strings.) This lets the linker move some symbols to the readonly data section. For example, previously: 0000000000000000 d _ZL18can_use_agent_enum is now: 0000000000000030 r _ZL18can_use_agent_enum 2020-09-14 Tom Tromey <tromey@adacore.com> * x86-tdep.h (x86_in_indirect_branch_thunk): Update. * x86-tdep.c (x86_is_thunk_register_name) (x86_in_indirect_branch_thunk): Update. * sparc64-tdep.c (sparc64_fpu_register_names) (sparc64_cp0_register_names, sparc64_register_names) (sparc64_pseudo_register_names): Now const. * sparc-tdep.h (struct gdbarch_tdep) <fpu_register_names, cp0_registers_num>: Now const. * sparc-tdep.c (sparc_core_register_names) (sparc32_fpu_register_names, sparc32_cp0_register_names) (sparc32_pseudo_register_names): Now const. (validate_tdesc_registers): Update. * rust-lang.c (rust_extensions): Now const. * p-lang.c (p_extensions): Now const. * objc-lang.c (objc_extensions): Now const. * nto-tdep.c (nto_thread_state_str): Now const. * moxie-tdep.c (moxie_register_names): Now const. * mips-tdep.h (struct gdbarch_tdep) <mips_processor_reg_names>: Now const. * mips-tdep.c (mips_generic_reg_names, mips_tx39_reg_names) (mips_linux_reg_names): Now const. (mips_gdbarch_init): Update. * microblaze-tdep.c (microblaze_register_names): Now const. * m68k-tdep.c (m68k_register_names): Now const. * m32r-tdep.c (m32r_register_names): Now const. * ia64-tdep.c (ia64_register_names): Now const. * i386-tdep.h (struct gdbarch_tdep) <register_names, ymmh_register_names, ymm16h_regnum, mpx_register_names, k_register_names, zmmh_register_names, xmm_avx512_register_names, ymm_avx512_register_names, pkeys_register_names>: Now const. * i386-tdep.c (i386_register_names, i386_zmm_names) (i386_zmmh_names, i386_k_names, i386_ymm_names, i386_ymmh_names) (i386_mpx_names, i386_pkeys_names, i386_bnd_names) (i386_mmx_names, i386_byte_names, i386_word_names): Now const. * f-lang.c (f_extensions): Now const. * d-lang.c (d_extensions): Now const. * csky-tdep.c (csky_register_names): Now const. * charset.c (default_charset_names, charset_enum): Now const. (_initialize_charset): Update. * c-lang.c (c_extensions, cplus_extensions, asm_extensions): Now const. * bsd-uthread.c (bsd_uthread_solib_names): Now const. (bsd_uthread_solib_loaded): Update. (bsd_uthread_state): Now const. * amd64-tdep.c (amd64_register_names, amd64_ymm_names) (amd64_ymm_avx512_names, amd64_ymmh_names) (amd64_ymmh_avx512_names, amd64_mpx_names, amd64_k_names) (amd64_zmmh_names, amd64_zmm_names, amd64_xmm_avx512_names) (amd64_pkeys_names, amd64_byte_names, amd64_word_names) (amd64_dword_names): Now const. * agent.c (can_use_agent_enum): Now const. * ada-tasks.c (task_states, long_task_states): Now const. * ada-lang.c (known_runtime_file_name_patterns) (known_auxiliary_function_name_patterns, attribute_names) (standard_exc, ada_extensions): Now const. gdbserver/ChangeLog 2020-09-14 Tom Tromey <tromey@adacore.com> * tracepoint.cc (eval_result_names): Now const. * ax.cc (gdb_agent_op_names): Now const.
2020-09-15 02:09:59 +08:00
x86_in_indirect_branch_thunk (CORE_ADDR pc, const char * const *register_names,
infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
2018-02-14 21:30:57 +08:00
int lo, int hi)
{
struct bound_minimal_symbol bmfun = lookup_minimal_symbol_by_pc (pc);
if (bmfun.minsym == nullptr)
return false;
Replace the MSYMBOL_*_NAME macros with member functions Improves readability. In the future, it will also allow making the name private, once the name setter functions become member functions. gdb/ChangeLog: 2019-11-22 Christian Biesinger <cbiesinger@google.com> * ada-lang.c (ada_lookup_simple_minsym): Update. (ada_collect_symbol_completion_matches): Update. * ada-tasks.c (read_atcb): Update. * amd64-windows-tdep.c (amd64_skip_main_prologue): Update. (amd64_windows_skip_trampoline_code): Update. * arm-tdep.c (skip_prologue_function): Update. (arm_skip_stack_protector): Update. * arm-wince-tdep.c (arm_pe_skip_trampoline_code): Update. (arm_wince_skip_main_prologue): Update. * ax-gdb.c (gen_expr): Update. * block.c (call_site_for_pc): Update. * blockframe.c (find_pc_partial_function): Update. * breakpoint.c (set_breakpoint_location_function): Update. * btrace.c (ftrace_print_function_name): Update. (ftrace_function_switched): Update. * c-valprint.c (print_unpacked_pointer): Update. * coffread.c (coff_symfile_read): Update. * compile/compile-c-symbols.c (convert_symbol_bmsym): Update. * compile/compile-cplus-symbols.c (convert_symbol_bmsym): Update. * dwarf-index-write.c (write_psymbols): Update. * dwarf2loc.c (call_site_to_target_addr): Update. (func_verify_no_selftailcall): Update. (tailcall_dump): Update. (call_site_find_chain_1): Update. (dwarf_expr_reg_to_entry_parameter): Update. * elfread.c (elf_gnu_ifunc_record_cache): Update. * eval.c (evaluate_funcall): Update. (evaluate_subexp_standard): Update. (evaluate_subexp_for_sizeof): Update. * expprint.c (print_subexp_standard): Update. (dump_subexp_body_standard): Update. * frame.c (get_prev_frame_always_1): Update. * frv-tdep.c (frv_skip_main_prologue): Update. * gnu-v2-abi.c (gnuv2_value_rtti_type): Update. * gnu-v3-abi.c (gnuv3_rtti_type): Update. (gnuv3_get_typename_from_type_info): Update. (gnuv3_skip_trampoline): Update. * hppa-tdep.c (hppa_lookup_stub_minimal_symbol): Update. * i386-tdep.c (i386_skip_main_prologue): Update. (i386_pe_skip_trampoline_code): Update. * ia64-tdep.c (ia64_convert_from_func_ptr_addr): Update. * infcall.c (get_function_name): Update. * linespec.c (minsym_found): Update. * linux-fork.c (info_checkpoints_command): Update. * m32c-tdep.c (m32c_m16c_address_to_pointer): Update. (m32c_m16c_pointer_to_address): Update. * maint.c (maintenance_translate_address): Update. * minsyms.c (add_minsym_to_hash_table): Update. (add_minsym_to_demangled_hash_table): Update. (lookup_minimal_symbol_mangled): Update. (lookup_minimal_symbol_demangled): Update. (lookup_minimal_symbol_linkage): Update. (lookup_minimal_symbol_text): Update. (lookup_minimal_symbol_by_pc_name): Update. (minimal_symbol_is_less_than): Update. (compact_minimal_symbols): Update. (build_minimal_symbol_hash_tables): Update. (find_solib_trampoline_target): Update. * mips-tdep.c (mips_stub_frame_sniffer): Update. (mips_skip_pic_trampoline_code): Update. * msp430-tdep.c (msp430_skip_trampoline_code): Update. * objc-lang.c (info_selectors_command): Update. (info_classes_command): Update. (find_methods): Update. (find_imps): Update. * p-valprint.c (pascal_val_print): Update. * ppc-linux-tdep.c (powerpc_linux_in_dynsym_resolve_code): Update. * ppc-sysv-tdep.c (convert_code_addr_to_desc_addr): Update. * printcmd.c (build_address_symbolic): Update. (info_symbol_command): Update. * psymtab.c (psymbol_name_matches): Update. (match_partial_symbol): Update. (lookup_partial_symbol): Update. (print_partial_symbols): Update. (sort_pst_symbols): Update. (maintenance_check_psymtabs): Update. * python/py-framefilter.c (py_print_frame): Update. * python/python.c (gdbpy_rbreak): Update. * record-btrace.c (btrace_get_bfun_name): Update. (btrace_call_history): Update. * rs6000-tdep.c (rs6000_skip_main_prologue): Update. (rs6000_skip_trampoline_code): Update. * sol-thread.c (info_cb): Update. * stabsread.c (scan_file_globals): Update. * stack.c (find_frame_funname): Update. (info_frame_command_core): Update. * symmisc.c (dump_msymbols): Update. * symtab.c (symbol_natural_name): Rename to.., (general_symbol_info::natural_name): ...this. (symbol_demangled_name): Rename to... (general_symbol_info::demangled_name): ...this. (symbol_search_name): Rename to... (general_symbol_info::search_name): ...this. (symbol_matches_search_name): Update. (find_pc_sect_line): Update. (skip_prologue_sal): Update. (search_symbols): Update. (print_msymbol_info): Update. (rbreak_command): Update. (completion_list_add_msymbol): Update. (completion_list_objc_symbol): Update. (get_msymbol_address): Update. * symtab.h (struct general_symbol_info): Add member functions natural_name (), linkage_name (), print_name (), demangled_name (), and search_name (). (SYMBOL_NATURAL_NAME): Update. (symbol_natural_name): Move to a member function on general_symbol_info. (SYMBOL_DEMANGLED_NAME): Update. (symbol_demangled_name): Move to a member function on general_symbol_info. (SYMBOL_SEARCH_NAME): Update. (symbol_search_name): Move to a member function on general_symbol_info. (MSYMBOL_NATURAL_NAME): Remove. (MSYMBOL_LINKAGE_NAME): Remove. (MSYMBOL_PRINT_NAME): Remove. (MSYMBOL_DEMANGLED_NAME): Remove. (MSYMBOL_SEARCH_NAME): Remove. * x86-tdep.c (x86_in_indirect_branch_thunk): Update. Change-Id: I65aa529843a9903e174ce799037e41f954a9fcee
2019-11-23 02:05:14 +08:00
const char *name = bmfun.minsym->linkage_name ();
infrun: step through indirect branch thunks With version 7.3 GCC supports new options -mindirect-branch=<choice> -mfunction-return=<choice> The choices are: keep behaves as before thunk jumps through a thunk thunk-external jumps through an external thunk thunk-inline jumps through an inlined thunk For thunk and thunk-external, GDB would, on a call to the thunk, step into the thunk and then resume to its caller assuming that this is an undebuggable function. On a return thunk, GDB would stop inside the thunk. Make GDB step through such thunks instead. Before: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) 30 } After: Temporary breakpoint 1, main () at gdb.base/step-indirect-call-thunk.c:37 37 x = apply (inc, 41); (gdb) s apply (op=0x80483e6 <inc>, x=41) at gdb.base/step-indirect-call-thunk.c:29 29 return op (x); (gdb) inc (x=41) at gdb.base/step-indirect-call-thunk.c:23 23 return x + 1; This is independent of the step-mode. In order to step into the thunk, you would need to use stepi. When stepping over an indirect call thunk, GDB would first step through the thunk, then recognize that it stepped into a sub-routine and resume to the caller (of the thunk). Not sure whether this is worth optimizing. Thunk detection is implemented via gdbarch. I implemented the methods for IA. Other architectures may run into unexpected fails. The tests assume a fixed number of instruction steps to reach a thunk. This depends on the compiler as well as the architecture. They may need adjustments when we add support for more architectures. Or we can simply drop those tests that cover being able to step into thunks using instruction stepping. When using an older GCC, the tests will fail to build and will be reported as untested: Running .../gdb.base/step-indirect-call-thunk.exp ... gdb compile failed, \ gcc: error: unrecognized command line option '-mindirect-branch=thunk' gcc: error: unrecognized command line option '-mfunction-return=thunk' === gdb Summary === # of untested testcases 1 gdb/ * infrun.c (process_event_stop_test): Call gdbarch_in_indirect_branch_thunk. * gdbarch.sh (in_indirect_branch_thunk): New. * gdbarch.c: Regenerated. * gdbarch.h: Regenerated. * x86-tdep.h: New. * x86-tdep.c: New. * Makefile.in (ALL_TARGET_OBS): Add x86-tdep.o. (HFILES_NO_SRCDIR): Add x86-tdep.h. (ALLDEPFILES): Add x86-tdep.c. * arch-utils.h (default_in_indirect_branch_thunk): New. * arch-utils.c (default_in_indirect_branch_thunk): New. * i386-tdep: Include x86-tdep.h. (i386_in_indirect_branch_thunk): New. (i386_elf_init_abi): Set in_indirect_branch_thunk gdbarch function. * amd64-tdep: Include x86-tdep.h. (amd64_in_indirect_branch_thunk): New. (amd64_init_abi): Set in_indirect_branch_thunk gdbarch function. testsuite/ * gdb.base/step-indirect-call-thunk.exp: New. * gdb.base/step-indirect-call-thunk.c: New. * gdb.reverse/step-indirect-call-thunk.exp: New. * gdb.reverse/step-indirect-call-thunk.c: New.
2018-02-14 21:30:57 +08:00
if (name == nullptr)
return false;
/* Check the indirect return thunk first. */
if (strcmp (name, "__x86_return_thunk") == 0)
return true;
/* Then check a family of indirect call/jump thunks. */
static const char thunk[] = "__x86_indirect_thunk";
static const size_t length = sizeof (thunk) - 1;
if (strncmp (name, thunk, length) != 0)
return false;
/* If that's the complete name, we're in the memory thunk. */
name += length;
if (*name == '\0')
return true;
/* Check for suffixes. */
if (*name++ != '_')
return false;
if (x86_is_thunk_register_name (name, register_names, lo, hi))
return true;
return false;
}