The comment on the gdbarch_displaced_step_fixup gdbarch method
indicates that this method is optional and that GDB will perform some
default if this method is not supplied. As such we define a predicate
gdbarch_displaced_step_fixup_p.
It may have been true at one point that the fixup method was optional,
but it is no longer true. If this method is not defined and GDB tries
to complete a displaced step, then GDB is going to crash.
Additionally the gdbarch_displaced_step_fixup_p predicate is not used
anywhere in GDB.
In this commit I have removed the gdbarch_displaced_step_fixup_p
predicate, and I have updated the validation check for the
gdbarch_displaced_step_fixup method; if the
gdbarch_displaced_step_copy_insn method is defined then the fixup
method must also be defined.
I believe I've manually checked all the current places where
gdbarch_displaced_step_copy_insn is defined and they all also define
the fixup method, so this change should cause no problems for anyone.
There should be no user visible changes after this commit.
---
gdb/gdbarch-components.py | 4 ++--
gdb/gdbarch-gen.h | 2 --
gdb/gdbarch.c | 14 ++------------
3 files changed, 4 insertions(+), 16 deletions(-)
@@ -1851,9 +1851,9 @@ see the comments in infrun.c.
("CORE_ADDR", "to"),
("struct regcache *", "regs"),
],
- predicate=True,
+ predicate=False,
predefault="NULL",
- invalid=True,
+ invalid="(gdbarch->displaced_step_copy_insn == nullptr) != (gdbarch->displaced_step_fixup == nullptr)",
)
Method(
@@ -1085,8 +1085,6 @@ extern void set_gdbarch_displaced_step_hw_singlestep (struct gdbarch *gdbarch, g
For a general explanation of displaced stepping and how GDB uses it,
see the comments in infrun.c. */
-extern bool gdbarch_displaced_step_fixup_p (struct gdbarch *gdbarch);
-
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);
extern void set_gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, gdbarch_displaced_step_fixup_ftype *displaced_step_fixup);
@@ -447,7 +447,8 @@ verify_gdbarch (struct gdbarch *gdbarch)
/* Skip verify of max_insn_length, has predicate. */
/* Skip verify of displaced_step_copy_insn, has predicate. */
/* Skip verify of displaced_step_hw_singlestep, invalid_p == 0 */
- /* Skip verify of displaced_step_fixup, has predicate. */
+ if ((gdbarch->displaced_step_copy_insn == nullptr) != (gdbarch->displaced_step_fixup == nullptr))
+ log.puts ("\n\tdisplaced_step_fixup");
/* Skip verify of displaced_step_prepare, has predicate. */
if ((! gdbarch->displaced_step_finish) != (! gdbarch->displaced_step_prepare))
log.puts ("\n\tdisplaced_step_finish");
@@ -1087,9 +1088,6 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
gdb_printf (file,
"gdbarch_dump: displaced_step_hw_singlestep = <%s>\n",
host_address_to_string (gdbarch->displaced_step_hw_singlestep));
- gdb_printf (file,
- "gdbarch_dump: gdbarch_displaced_step_fixup_p() = %d\n",
- gdbarch_displaced_step_fixup_p (gdbarch));
gdb_printf (file,
"gdbarch_dump: displaced_step_fixup = <%s>\n",
host_address_to_string (gdbarch->displaced_step_fixup));
@@ -4046,19 +4044,11 @@ set_gdbarch_displaced_step_hw_singlestep (struct gdbarch *gdbarch,
gdbarch->displaced_step_hw_singlestep = displaced_step_hw_singlestep;
}
-bool
-gdbarch_displaced_step_fixup_p (struct gdbarch *gdbarch)
-{
- gdb_assert (gdbarch != NULL);
- return gdbarch->displaced_step_fixup != NULL;
-}
-
void
gdbarch_displaced_step_fixup (struct gdbarch *gdbarch, struct displaced_step_copy_insn_closure *closure, CORE_ADDR from, CORE_ADDR to, struct regcache *regs)
{
gdb_assert (gdbarch != NULL);
gdb_assert (gdbarch->displaced_step_fixup != NULL);
- /* Do not check predicate: gdbarch->displaced_step_fixup != NULL, allow call. */
if (gdbarch_debug >= 2)
gdb_printf (gdb_stdlog, "gdbarch_displaced_step_fixup called\n");
gdbarch->displaced_step_fixup (gdbarch, closure, from, to, regs);