aarch64_displaced_step_fixup (struct gdbarch *gdbarch,
struct displaced_step_copy_insn_closure *dsc_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
- aarch64_displaced_step_copy_insn_closure *dsc
- = (aarch64_displaced_step_copy_insn_closure *) dsc_;
+ CORE_ADDR pc = regcache_read_pc (regs);
- ULONGEST pc;
+ /* If the displaced instruction didn't complete successfully then all we
+ need to do is restore the program counter. */
+ if (!completed_p)
+ {
+ pc = from + (pc - to);
+ regcache_write_pc (regs, pc);
+ return;
+ }
- regcache_cooked_read_unsigned (regs, AARCH64_PC_REGNUM, &pc);
+ aarch64_displaced_step_copy_insn_closure *dsc
+ = (aarch64_displaced_step_copy_insn_closure *) dsc_;
displaced_debug_printf ("PC after stepping: %s (was %s).",
paddress (gdbarch, pc), paddress (gdbarch, to));
void aarch64_displaced_step_fixup (struct gdbarch *gdbarch,
displaced_step_copy_insn_closure *dsc,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs);
+ struct regcache *regs, bool completed_p);
bool aarch64_displaced_step_hw_singlestep (struct gdbarch *gdbarch);
amd64_displaced_step_fixup (struct gdbarch *gdbarch,
struct displaced_step_copy_insn_closure *dsc_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
amd64_displaced_step_copy_insn_closure *dsc
= (amd64_displaced_step_copy_insn_closure *) dsc_;
the displaced instruction; make it relative to the original insn.
Well, signal handler returns don't need relocation either, but we use the
value of %rip to recognize those; see below. */
- if (! amd64_absolute_jmp_p (insn_details)
- && ! amd64_absolute_call_p (insn_details)
- && ! amd64_ret_p (insn_details))
+ if (!completed_p
+ || (!amd64_absolute_jmp_p (insn_details)
+ && !amd64_absolute_call_p (insn_details)
+ && !amd64_ret_p (insn_details)))
{
- ULONGEST orig_rip;
int insn_len;
- regcache_cooked_read_unsigned (regs, AMD64_RIP_REGNUM, &orig_rip);
+ CORE_ADDR pc = regcache_read_pc (regs);
/* A signal trampoline system call changes the %rip, resuming
execution of the main program after the signal handler has
it unrelocated. Goodness help us if there are PC-relative
system calls. */
if (amd64_syscall_p (insn_details, &insn_len)
- && orig_rip != to + insn_len
/* GDB can get control back after the insn after the syscall.
- Presumably this is a kernel bug.
- Fixup ensures its a nop, we add one to the length for it. */
- && orig_rip != to + insn_len + 1)
+ Presumably this is a kernel bug. Fixup ensures its a nop, we
+ add one to the length for it. */
+ && (pc < to || pc > (to + insn_len + 1)))
displaced_debug_printf ("syscall changed %%rip; not relocating");
else
{
- ULONGEST rip = orig_rip - insn_offset;
+ CORE_ADDR rip = pc - insn_offset;
/* If we just stepped over a breakpoint insn, we don't backup
the pc on purpose; this is to match behaviour without
stepping. */
- regcache_cooked_write_unsigned (regs, AMD64_RIP_REGNUM, rip);
+ regcache_write_pc (regs, rip);
displaced_debug_printf ("relocated %%rip from %s to %s",
- paddress (gdbarch, orig_rip),
+ paddress (gdbarch, pc),
paddress (gdbarch, rip));
}
}
/* If the instruction was a call, the return address now atop the
stack is the address following the copied instruction. We need
to make it the address following the original instruction. */
- if (amd64_call_p (insn_details))
+ if (completed_p && amd64_call_p (insn_details))
{
ULONGEST rsp;
ULONGEST retaddr;
struct regcache *regs);
extern void amd64_displaced_step_fixup
(struct gdbarch *gdbarch, displaced_step_copy_insn_closure *closure,
- CORE_ADDR from, CORE_ADDR to, struct regcache *regs);
+ CORE_ADDR from, CORE_ADDR to, struct regcache *regs, bool completed_p);
/* Initialize the ABI for amd64. Uses DEFAULT_TDESC as fallback
tdesc, if INFO does not specify one. */
arm_displaced_step_fixup (struct gdbarch *gdbarch,
struct displaced_step_copy_insn_closure *dsc_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
+ /* The following block exists as a temporary measure while displaced
+ stepping is fixed architecture at a time within GDB.
+
+ In an earlier implementation of displaced stepping, if GDB thought the
+ displaced instruction had not been executed then this fix up function
+ was never called. As a consequence, things that should be fixed by
+ this function were left in an unfixed state.
+
+ However, it's not as simple as always calling this function; this
+ function needs to be updated to decide what should be fixed up based
+ on whether the displaced step executed or not, which requires each
+ architecture to be considered individually.
+
+ Until this architecture is updated, this block replicates the old
+ behaviour; we just restore the program counter register, and leave
+ everything else unfixed. */
+ if (!completed_p)
+ {
+ CORE_ADDR pc = regcache_read_pc (regs);
+ pc = from + (pc - to);
+ regcache_write_pc (regs, pc);
+ return;
+ }
+
arm_displaced_step_copy_insn_closure *dsc
= (arm_displaced_step_copy_insn_closure *) dsc_;
extern void arm_displaced_step_fixup (struct gdbarch *,
displaced_step_copy_insn_closure *,
- CORE_ADDR, CORE_ADDR, struct regcache *);
+ CORE_ADDR, CORE_ADDR,
+ struct regcache *, bool);
/* Return the bit mask in ARM_PS_REGNUM that indicates Thumb mode. */
extern int arm_psr_thumb_bit (struct gdbarch *);
bool instruction_executed_successfully
= displaced_step_instruction_executed_successfully (arch, status);
- if (instruction_executed_successfully)
- {
- gdbarch_displaced_step_fixup (arch, copy_insn_closure.get (),
- buffer->original_pc,
- buffer->addr, rc);
- return DISPLACED_STEP_FINISH_STATUS_OK;
- }
- else
- {
- /* Since the instruction didn't complete, all we can do is relocate the
- PC. */
- CORE_ADDR pc = regcache_read_pc (rc);
- pc = buffer->original_pc + (pc - buffer->addr);
- regcache_write_pc (rc, pc);
- return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED;
- }
+ gdbarch_displaced_step_fixup (arch, copy_insn_closure.get (),
+ buffer->original_pc, buffer->addr,
+ rc, instruction_executed_successfully);
+
+ return (instruction_executed_successfully
+ ? DISPLACED_STEP_FINISH_STATUS_OK
+ : DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED);
}
const displaced_step_copy_insn_closure *
extern bool gdbarch_displaced_step_hw_singlestep (struct gdbarch *gdbarch);
extern void set_gdbarch_displaced_step_hw_singlestep (struct gdbarch *gdbarch, gdbarch_displaced_step_hw_singlestep_ftype *displaced_step_hw_singlestep);
-/* Fix up the state resulting from successfully single-stepping a
- displaced instruction, to give the result we would have gotten from
- stepping the instruction in its original location.
+/* Fix up the state after attempting to single-step a displaced
+ instruction, to give the result we would have gotten from stepping the
+ instruction in its original location.
REGS is the register state resulting from single-stepping the
displaced instruction.
CLOSURE is the result from the matching call to
gdbarch_displaced_step_copy_insn.
- If you provide gdbarch_displaced_step_copy_insn.but not this
- function, then GDB assumes that no fixup is needed after
- single-stepping the instruction.
+ FROM is the address where the instruction was original located, TO is
+ the address of the displaced buffer where the instruction was copied
+ to for stepping.
+
+ COMPLETED_P is true if GDB stopped as a result of the requested step
+ having completed (e.g. the inferior stopped with SIGTRAP), otherwise
+ COMPLETED_P is false and GDB stopped for some other reason. In the
+ case where a single instruction is expanded to multiple replacement
+ instructions for stepping then it may be necessary to read the current
+ program counter from REGS in order to decide how far through the
+ series of replacement instructions the inferior got before stopping,
+ this may impact what will need fixing up in this function.
For a general explanation of displaced stepping and how GDB uses it,
see the comments in infrun.c. */
-typedef void (gdbarch_displaced_step_fixup_ftype) (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs);
-extern void gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs);
+typedef void (gdbarch_displaced_step_fixup_ftype) (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs, bool completed_p);
+extern void gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs, bool completed_p);
extern void set_gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, gdbarch_displaced_step_fixup_ftype *displaced_step_fixup);
/* Prepare THREAD for it to displaced step the instruction at its current PC.
}
void
-gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs)
+gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs, bool completed_p)
{
gdb_assert (gdbarch != NULL);
gdb_assert (gdbarch->displaced_step_fixup != NULL);
if (gdbarch_debug >= 2)
gdb_printf (gdb_stdlog, "gdbarch_displaced_step_fixup called\n");
- gdbarch->displaced_step_fixup (gdbarch, closure, from, to, regs);
+ gdbarch->displaced_step_fixup (gdbarch, closure, from, to, regs, completed_p);
}
void
Method(
comment="""
-Fix up the state resulting from successfully single-stepping a
-displaced instruction, to give the result we would have gotten from
-stepping the instruction in its original location.
+Fix up the state after attempting to single-step a displaced
+instruction, to give the result we would have gotten from stepping the
+instruction in its original location.
REGS is the register state resulting from single-stepping the
displaced instruction.
CLOSURE is the result from the matching call to
gdbarch_displaced_step_copy_insn.
-If you provide gdbarch_displaced_step_copy_insn.but not this
-function, then GDB assumes that no fixup is needed after
-single-stepping the instruction.
+FROM is the address where the instruction was original located, TO is
+the address of the displaced buffer where the instruction was copied
+to for stepping.
+
+COMPLETED_P is true if GDB stopped as a result of the requested step
+having completed (e.g. the inferior stopped with SIGTRAP), otherwise
+COMPLETED_P is false and GDB stopped for some other reason. In the
+case where a single instruction is expanded to multiple replacement
+instructions for stepping then it may be necessary to read the current
+program counter from REGS in order to decide how far through the
+series of replacement instructions the inferior got before stopping,
+this may impact what will need fixing up in this function.
For a general explanation of displaced stepping and how GDB uses it,
see the comments in infrun.c.
("CORE_ADDR", "from"),
("CORE_ADDR", "to"),
("struct regcache *", "regs"),
+ ("bool", "completed_p")
],
predicate=False,
predefault="NULL",
i386_displaced_step_fixup (struct gdbarch *gdbarch,
struct displaced_step_copy_insn_closure *closure_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
the displaced instruction; make it relative. Well, signal
handler returns don't need relocation either, but we use the
value of %eip to recognize those; see below. */
- if (! i386_absolute_jmp_p (insn)
- && ! i386_absolute_call_p (insn)
- && ! i386_ret_p (insn))
+ if (!completed_p
+ || (!i386_absolute_jmp_p (insn)
+ && !i386_absolute_call_p (insn)
+ && !i386_ret_p (insn)))
{
- ULONGEST orig_eip;
int insn_len;
- regcache_cooked_read_unsigned (regs, I386_EIP_REGNUM, &orig_eip);
+ CORE_ADDR pc = regcache_read_pc (regs);
/* A signal trampoline system call changes the %eip, resuming
execution of the main program after the signal handler has
it unrelocated. Goodness help us if there are PC-relative
system calls. */
if (i386_syscall_p (insn, &insn_len)
- && orig_eip != to + (insn - insn_start) + insn_len
+ && pc != to + (insn - insn_start) + insn_len
/* GDB can get control back after the insn after the syscall.
Presumably this is a kernel bug.
i386_displaced_step_copy_insn ensures its a nop,
we add one to the length for it. */
- && orig_eip != to + (insn - insn_start) + insn_len + 1)
+ && pc != to + (insn - insn_start) + insn_len + 1)
displaced_debug_printf ("syscall changed %%eip; not relocating");
else
{
- ULONGEST eip = (orig_eip - insn_offset) & 0xffffffffUL;
+ ULONGEST eip = (pc - insn_offset) & 0xffffffffUL;
/* If we just stepped over a breakpoint insn, we don't backup
the pc on purpose; this is to match behaviour without
stepping. */
- regcache_cooked_write_unsigned (regs, I386_EIP_REGNUM, eip);
+ regcache_write_pc (regs, eip);
displaced_debug_printf ("relocated %%eip from %s to %s",
- paddress (gdbarch, orig_eip),
+ paddress (gdbarch, pc),
paddress (gdbarch, eip));
}
}
/* If the instruction was a call, the return address now atop the
stack is the address following the copied instruction. We need
to make it the address following the original instruction. */
- if (i386_call_p (insn))
+ if (completed_p && i386_call_p (insn))
{
ULONGEST esp;
ULONGEST retaddr;
struct regcache *regs);
extern void i386_displaced_step_fixup
(struct gdbarch *gdbarch, displaced_step_copy_insn_closure *closure,
- CORE_ADDR from, CORE_ADDR to, regcache *regs);
+ CORE_ADDR from, CORE_ADDR to, regcache *regs, bool completed_p);
/* Initialize a basic ELF architecture variant. */
extern void i386_elf_init_abi (struct gdbarch_info, struct gdbarch *);
ppc_displaced_step_fixup (struct gdbarch *gdbarch,
struct displaced_step_copy_insn_closure *closure_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
+ /* If the displaced instruction didn't complete successfully then all we
+ need to do is restore the program counter. */
+ if (!completed_p)
+ {
+ CORE_ADDR pc = regcache_read_pc (regs);
+ pc = from + (pc - to);
+ regcache_write_pc (regs, pc);
+ return;
+ }
+
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
/* Our closure is a copy of the instruction. */
ppc_displaced_step_copy_insn_closure *closure
s390_displaced_step_fixup (struct gdbarch *gdbarch,
displaced_step_copy_insn_closure *closure_,
CORE_ADDR from, CORE_ADDR to,
- struct regcache *regs)
+ struct regcache *regs, bool completed_p)
{
+ CORE_ADDR pc = regcache_read_pc (regs);
+
+ /* If the displaced instruction didn't complete successfully then all we
+ need to do is restore the program counter. */
+ if (!completed_p)
+ {
+ pc = from + (pc - to);
+ regcache_write_pc (regs, pc);
+ return;
+ }
+
/* Our closure is a copy of the instruction. */
s390_displaced_step_copy_insn_closure *closure
= (s390_displaced_step_copy_insn_closure *) closure_;
unsigned int b2, r1, r2, x2, r3;
int i2, d2;
- /* Get current PC and addressing mode bit. */
- CORE_ADDR pc = regcache_read_pc (regs);
+ /* Get addressing mode bit. */
ULONGEST amode = 0;
-
if (register_size (gdbarch, S390_PSWA_REGNUM) == 4)
{
regcache_cooked_read_unsigned (regs, S390_PSWA_REGNUM, &amode);
--- /dev/null
+/* This file is part of GDB, the GNU debugger.
+
+ Copyright 2023 Free Software Foundation, Inc.
+
+ 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 <unistd.h>
+
+void
+setup_alarm (void)
+{
+ alarm (300);
+}
--- /dev/null
+/* Copyright 2009-2023 Free Software Foundation, Inc.
+
+ 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/>.
+
+ This file is part of the gdb testsuite.
+ It tests displaced stepping over various insns that require special
+ handling. */
+
+ .text
+
+ .global main
+main:
+ nop
+
+ callq setup_alarm
+
+ nop
+
+/***********************************************/
+
+/* test call/ret */
+
+ .global test_call
+test_call:
+ call test_call
+ nop
+ .global test_ret_end
+test_ret_end:
+ nop
+
+/***********************************************/
+
+/* all done */
+
+done:
+ mov $0,%rdi
+ call exit
+ hlt
--- /dev/null
+# Copyright 2023 Free Software Foundation, Inc.
+
+# 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/>.
+
+# Test amd64 displaced stepping over a call instruction that calls to
+# itself. This is pretty unlikely to be seen in the wild, but does
+# test a corner case of our displaced step handling.
+
+require is_x86_64_m64_target
+
+set newline "\[\r\n\]*"
+
+set opts {debug nopie}
+standard_testfile .S -alarm.c
+
+if { [prepare_for_testing "failed to prepare" $testfile "$srcfile $srcfile2" $opts] } {
+ return -1
+}
+
+gdb_test "set displaced-stepping on" ""
+gdb_test "show displaced-stepping" ".* displaced stepping .* is on.*"
+
+if {![runto_main]} {
+ return 0
+}
+
+# Proceed to the test function.
+gdb_breakpoint "test_call"
+gdb_continue_to_breakpoint "test_call"
+
+# Get the current stack pointer value.
+set sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*"]
+
+# Get the address of the next instruction.
+set next_insn_addr ""
+gdb_test_multiple "x/2i \$pc" "get address of next insn" {
+ -re "\r\n=> $hex \[^\r\n\]+\r\n" {
+ exp_continue
+ }
+ -re "^ ($hex) \[^\r\n\]+\r\n" {
+ set next_insn_addr $expect_out(1,string)
+ exp_continue
+ }
+ -re "^$::gdb_prompt $" {
+ gdb_assert {![string equal $next_insn_addr ""]} \
+ $gdb_test_name
+ }
+}
+
+# Clear the slot on the stack and confirm it was set to zero.
+set sp [expr $sp - 0x8]
+gdb_test_no_output "set {unsigned long long} $sp = 0"
+set zero_val 0x[format %016x 0]
+gdb_test "x/1gx 0x[format %x $sp]" "$hex:\\s+${zero_val}" \
+ "check return address slot was set to zero"
+
+# Single step.
+gdb_test "stepi" \
+ "Breakpoint $decimal, test_call \\(\\) at .*"
+
+# Check stack pointer was updated to the expected value.
+set new_sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*" \
+ "get stack pointer after step"]
+gdb_assert {[expr $sp == $new_sp]} \
+ "check stack pointer was updated as expected"
+
+# Check the contents of the stack were updated to the expected value.
+set next_insn_addr 0x[format %016X $next_insn_addr]
+gdb_test "x/1gx 0x[format %x $sp]" "$hex:\\s+$next_insn_addr" \
+ "check return address was updated correctly"
--- /dev/null
+/* This file is part of GDB, the GNU debugger.
+
+ Copyright 2023 Free Software Foundation, Inc.
+
+ 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 <signal.h>
+#include <stdio.h>
+
+#ifdef SIGALRM
+
+static void
+sigalrm_handler (int sig)
+{
+}
+
+#endif
+
+void
+setup_signal_handler (void)
+{
+#ifdef SIGALRM
+ signal (SIGALRM, sigalrm_handler);
+#endif
+}
main:
nop
+ callq setup_signal_handler
+
+ nop
+
/***********************************************/
/* test call/ret */
test_rip_rdi_end:
nop
+ .global test_jmp
+test_jmp:
+ jmpq *jmp_dest(%rip)
+ nop
+ .global test_jmp_end
+test_jmp_end:
+ nop
+
/* skip over test data */
jmp done
answer: .8byte 42
+jmp_dest:
+ .8byte test_jmp_end
+
/***********************************************/
/* all done */
# Test amd64 displaced stepping.
-
require is_x86_64_m64_target
set newline "\[\r\n\]*"
set opts {debug nopie}
-standard_testfile .S
+standard_testfile .S -signal.c
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] } {
+if { [prepare_for_testing "failed to prepare" $testfile "$srcfile $srcfile2" $opts] } {
return -1
}
}
}
-# Verify all REGS equal VAL, except REG which equals REG_VAL.
+# Verify all REGS equal VAL, except EXCEPT_REG which equals
+# EXCEPT_REG_VAL.
+#
+# It is fine for EXCEPT_REG to be the empty string, in which case no
+# register will be checked for EXCEPT_REG_VAL.
-proc verify_regs { test_name regs val except_reg except_reg_val } {
+proc_with_prefix verify_regs { regs val except_reg except_reg_val } {
global newline
foreach reg ${regs} {
set expected ${except_reg_val}
}
# The cast to (int) is because RBP is printed as a pointer.
- gdb_test "p (int) \$${reg}" " = ${expected}${newline}" "${test_name} ${reg} expected value"
+ gdb_test "p (int) \$${reg}" " = ${expected}${newline}" "${reg} expected value"
}
}
-proc rip_test { reg } {
+# Run the rip-relative tests.
+#
+# TEST_START_LABEL and TEST_END_LABEL are two labels that delimit the
+# test in the srcfile.
+#
+# REG is either the name of a register which is the destination
+# location (when testing the add instruction), otherwise REG should be
+# the empty string, when testing the 'jmpq*' instruction.
+#
+# SIGNAL_MODES is a list which always contains 'off' and optionally
+# might also contain 'on'. The 'on' value is only included if the
+# target supports sending SIGALRM to the inferior. The test is
+# repeated for each signal mode. With signal mode 'on' we send a
+# signal to the inferior while it is performing a displaced step.
+proc rip_test { reg test_start_label test_end_label signal_modes } {
global srcfile rip_regs
- set test_start_label "test_rip_${reg}"
- set test_end_label "test_rip_${reg}_end"
-
gdb_test "break ${test_start_label}" \
"Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break ${test_end_label}" \
"Breakpoint.*at.* file .*$srcfile, line.*"
- gdb_test "continue" \
- "Continuing.*Breakpoint.*, ${test_start_label} ().*" \
- "continue to ${test_start_label}"
+ foreach_with_prefix send_signal $signal_modes {
+ if {$send_signal eq [lindex $signal_modes 0]} {
+ # The first time through we can just continue to the
+ # breakpoint.
+ gdb_test "continue" \
+ "Continuing.*Breakpoint.*, ${test_start_label} ().*" \
+ "continue to ${test_start_label}"
+ } else {
+ # For the second time through the test we need to jump
+ # back to the beginning.
+ gdb_test "jump ${test_start_label}" \
+ "Breakpoint.*, ${test_start_label} ().*" \
+ "jump back to ${test_start_label}"
+ }
+
+ set_regs ${rip_regs} 0
+
+ if {$send_signal} {
+ # The signal sending tests require that the signal appear to
+ # arrive from an outside source, i.e. we can't use GDB's 'signal'
+ # command to deliver it.
+ #
+ # The signal must arrive while GDB is processing the displaced
+ # step instruction.
+ #
+ # If we use 'signal' to send the signal GDB doesn't actually do
+ # the displaced step, but instead just delivers the signal.
+ set inferior_pid [get_inferior_pid]
+ remote_exec target "kill -ALRM $inferior_pid"
+ }
- set_regs ${rip_regs} 0
+ gdb_test "continue" \
+ "Continuing.*Breakpoint.*, ${test_end_label} ().*" \
+ "continue to ${test_end_label}"
- gdb_test "continue" \
- "Continuing.*Breakpoint.*, ${test_end_label} ().*" \
- "continue to ${test_end_label}"
+ verify_regs ${rip_regs} 0 ${reg} 42
+ }
+}
- verify_regs "test rip w/${reg}" ${rip_regs} 0 ${reg} 42
+if {![target_info exists gdb,nosignals] && ![istarget "*-*-mingw*"]} {
+ # Only targets that support SIGALRM can run the signal tests.
+ set signal_modes { off on }
+} else {
+ set signal_modes { off }
}
+# The rip-relative add instructions. There's a test writing to
+# each register in RIP_REGS in turn.
foreach reg ${rip_regs} {
- rip_test $reg
+ with_test_prefix "add into ${reg}" {
+ rip_test $reg "test_rip_${reg}" "test_rip_${reg}_end" $signal_modes
+ }
+}
+
+# Now test the rip-relative 'jmpq*' instruction.
+with_test_prefix "rip-relative jmpq*" {
+ rip_test "" "test_jmp" "test_jmp_end" $signal_modes
}
##########################################
--- /dev/null
+/* This file is part of GDB, the GNU debugger.
+
+ Copyright 2023 Free Software Foundation, Inc.
+
+ 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 <unistd.h>
+
+void
+setup_alarm (void)
+{
+ alarm (300);
+}
--- /dev/null
+/* Copyright 2009-2023 Free Software Foundation, Inc.
+
+ 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/>.
+
+ This file is part of the gdb testsuite.
+ It tests displaced stepping over various insns that require special
+ handling. */
+
+ .text
+
+ .global main
+main:
+ nop
+
+ call setup_alarm
+
+ nop
+
+/***********************************************/
+
+/* test call/ret */
+
+ .global test_call
+test_call:
+ call test_call
+ nop
+ .global test_ret_end
+test_ret_end:
+ nop
+
+/***********************************************/
+
+/* all done */
+
+done:
+ pushl $0
+ call exit
+ hlt
--- /dev/null
+# Copyright 2023 Free Software Foundation, Inc.
+
+# 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/>.
+
+# Test i386 displaced stepping over a call instruction that calls to
+# itself. This is pretty unlikely to be seen in the wild, but does
+# test a corner case of our displaced step handling.
+
+require is_x86_like_target
+
+set newline "\[\r\n\]*"
+
+set opts {debug nopie}
+standard_testfile .S -alarm.c
+
+if { [prepare_for_testing "failed to prepare" $testfile "$srcfile $srcfile2" $opts] } {
+ return -1
+}
+
+gdb_test "set displaced-stepping on" ""
+gdb_test "show displaced-stepping" ".* displaced stepping .* is on.*"
+
+if {![runto_main]} {
+ return 0
+}
+
+# Proceed to the test function.
+gdb_breakpoint "test_call"
+gdb_continue_to_breakpoint "test_call"
+
+# Get the current stack pointer value.
+set sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*"]
+
+# Get the address of the next instruction.
+set next_insn_addr ""
+gdb_test_multiple "x/2i \$pc" "get address of next insn" {
+ -re "\r\n=> $hex \[^\r\n\]+\r\n" {
+ exp_continue
+ }
+ -re "^ ($hex) \[^\r\n\]+\r\n" {
+ set next_insn_addr $expect_out(1,string)
+ exp_continue
+ }
+ -re "^$::gdb_prompt $" {
+ gdb_assert {![string equal $next_insn_addr ""]} \
+ $gdb_test_name
+ }
+}
+
+# Clear the slot on the stack and confirm it was set to zero.
+set sp [expr $sp - 0x4]
+gdb_test_no_output "set {unsigned long long} $sp = 0"
+set zero_val 0x[format %08x 0]
+gdb_test "x/1wx 0x[format %x $sp]" "$hex:\\s+${zero_val}" \
+ "check return address slot was set to zero"
+
+# Single step.
+gdb_test "stepi" \
+ "Breakpoint $decimal, test_call \\(\\) at .*"
+
+# Check stack pointer was updated to the expected value.
+set new_sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*" \
+ "get stack pointer after step"]
+gdb_assert {[expr $sp == $new_sp]} \
+ "check stack pointer was updated as expected"
+
+# Check the contents of the stack were updated to the expected value.
+set next_insn_addr 0x[format %08X $next_insn_addr]
+gdb_test "x/1wx 0x[format %x $sp]" "$hex:\\s+$next_insn_addr" \
+ "check return address was updated correctly"
projects / binutils-gdb.git / commitdiff