| Message ID | 20200113174239.7819-1-luis.machado@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,AArch64] Add more debugging output to aarch64_displaced_step_fixup | expand |
Ok to push. Alan. > On 13 Jan 2020, at 17:42, Luis Machado <luis.machado@linaro.org> wrote: > > New in v2: > > - Fixed misc comments from review. > > -- > > While debugging the step-over-syscall problem, i wanted to see a bit more > debugging output to try to determine the root cause. > > This patch does this. > > gdb/ChangeLog: > > 2020-01-13 Luis Machado <luis.machado@linaro.org> > > * aarch64-tdep.c (aarch64_displaced_step_fixup): Add more debugging > output. > --- > gdb/aarch64-tdep.c | 27 +++++++++++++++++++++++++-- > 1 file changed, 25 insertions(+), 2 deletions(-) > > diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c > index 6a9d34dc67..29b712c155 100644 > --- a/gdb/aarch64-tdep.c > +++ b/gdb/aarch64-tdep.c > @@ -3037,8 +3037,16 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, > > regcache_cooked_read_unsigned (regs, AARCH64_PC_REGNUM, &pc); > > + if (debug_displaced) > + debug_printf ("Displaced: PC after stepping: %s (was %s).\n", > + paddress (gdbarch, pc), paddress (gdbarch, to)); > + > if (dsc->cond) > { > + if (debug_displaced) > + debug_printf ("Displaced: [Conditional] pc_adjust before: %d\n", > + dsc->pc_adjust); > + > if (pc - to == 8) > { > /* Condition is true. */ > @@ -3050,8 +3058,18 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, > } > else > gdb_assert_not_reached ("Unexpected PC value after displaced stepping"); > + > + if (debug_displaced) > + debug_printf ("Displaced: [Conditional] pc_adjust after: %d\n", > + dsc->pc_adjust); > } > > + if (debug_displaced) > + debug_printf ("Displaced: %s PC by %d\n", > + dsc->pc_adjust? "adjusting" : "not adjusting", > + dsc->pc_adjust); > + > + > if (dsc->pc_adjust != 0) > { > /* Make sure the previous instruction was executed (that is, the PC > @@ -3059,11 +3077,16 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, > offset. Otherwise we may skip an instruction before its execution > took place. */ > if ((pc - to) == 0) > - dsc->pc_adjust = 0; > + { > + if (debug_displaced) > + debug_printf ("Displaced: PC did not move. Discarding PC " > + "adjustment.\n"); > + dsc->pc_adjust = 0; > + } > > if (debug_displaced) > { > - debug_printf ("displaced: fixup: set PC to %s:%d\n", > + debug_printf ("Displaced: fixup: set PC to %s:%d\n", > paddress (gdbarch, from), dsc->pc_adjust); > } > regcache_cooked_write_unsigned (regs, AARCH64_PC_REGNUM, > -- > 2.17.1 >
diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c index 6a9d34dc67..29b712c155 100644 --- a/gdb/aarch64-tdep.c +++ b/gdb/aarch64-tdep.c @@ -3037,8 +3037,16 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, regcache_cooked_read_unsigned (regs, AARCH64_PC_REGNUM, &pc); + if (debug_displaced) + debug_printf ("Displaced: PC after stepping: %s (was %s).\n", + paddress (gdbarch, pc), paddress (gdbarch, to)); + if (dsc->cond) { + if (debug_displaced) + debug_printf ("Displaced: [Conditional] pc_adjust before: %d\n", + dsc->pc_adjust); + if (pc - to == 8) { /* Condition is true. */ @@ -3050,8 +3058,18 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, } else gdb_assert_not_reached ("Unexpected PC value after displaced stepping"); + + if (debug_displaced) + debug_printf ("Displaced: [Conditional] pc_adjust after: %d\n", + dsc->pc_adjust); } + if (debug_displaced) + debug_printf ("Displaced: %s PC by %d\n", + dsc->pc_adjust? "adjusting" : "not adjusting", + dsc->pc_adjust); + + if (dsc->pc_adjust != 0) { /* Make sure the previous instruction was executed (that is, the PC @@ -3059,11 +3077,16 @@ aarch64_displaced_step_fixup (struct gdbarch *gdbarch, offset. Otherwise we may skip an instruction before its execution took place. */ if ((pc - to) == 0) - dsc->pc_adjust = 0; + { + if (debug_displaced) + debug_printf ("Displaced: PC did not move. Discarding PC " + "adjustment.\n"); + dsc->pc_adjust = 0; + } if (debug_displaced) { - debug_printf ("displaced: fixup: set PC to %s:%d\n", + debug_printf ("Displaced: fixup: set PC to %s:%d\n", paddress (gdbarch, from), dsc->pc_adjust); } regcache_cooked_write_unsigned (regs, AARCH64_PC_REGNUM,