: Fix PR19061, gdb hangs/spins-on-cpu when debugging any program on Alpha
Commit Message
On Sun, Dec 17, 2017 at 7:11 PM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Fri, Dec 15, 2017 at 7:21 PM, Pedro Alves <palves@redhat.com> wrote:
>> On 12/15/2017 12:11 PM, Uros Bizjak wrote:
>>>
>>> Please note that I have no commit access, so if approved, please
>>> commit the patch to the source repository for me.
>>
>> Merged.
>
> Thanks!
>
> Attached, please find a patch for gdb-8.0 branch. The patch is tested
> in the same way as the patch for mainline, with native
> alphaev68-linux-gnu build and tests and with gcc's guality.exp and
> simulate-thread.exp testcases.
This one is the correct one.
Sorry, for the confusion,
Uros.
Comments
On 12/17/2017 07:14 PM, Uros Bizjak wrote:
> On Sun, Dec 17, 2017 at 7:11 PM, Uros Bizjak <ubizjak@gmail.com> wrote:
>> Attached, please find a patch for gdb-8.0 branch. The patch is tested
>> in the same way as the patch for mainline, with native
>> alphaev68-linux-gnu build and tests and with gcc's guality.exp and
>> simulate-thread.exp testcases.
>
> This one is the correct one.
Merged.
Thanks,
Pedro Alves
@@ -766,10 +766,8 @@ static const int stq_c_opcode = 0x2f;
the sequence. */
static VEC (CORE_ADDR) *
-alpha_deal_with_atomic_sequence (struct regcache *regcache)
+alpha_deal_with_atomic_sequence (struct gdbarch *gdbarch, CORE_ADDR pc)
{
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
- CORE_ADDR pc = regcache_read_pc (regcache);
CORE_ADDR breaks[2] = {-1, -1};
CORE_ADDR loc = pc;
CORE_ADDR closing_insn; /* Instruction that closes the atomic sequence. */
@@ -1721,12 +1719,17 @@ VEC (CORE_ADDR) *
alpha_software_single_step (struct regcache *regcache)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
- CORE_ADDR pc;
- VEC (CORE_ADDR) *next_pcs = NULL;
+ CORE_ADDR pc, next_pc;
+ VEC (CORE_ADDR) *next_pcs;
pc = regcache_read_pc (regcache);
+ next_pcs = alpha_deal_with_atomic_sequence (gdbarch, pc);
+ if (next_pcs != NULL)
+ return next_pcs;
+
+ next_pc = alpha_next_pc (regcache, pc);
- VEC_safe_push (CORE_ADDR, next_pcs, alpha_next_pc (regcache, pc));
+ VEC_safe_push (CORE_ADDR, next_pcs, next_pc);
return next_pcs;
}
@@ -1826,7 +1829,7 @@ alpha_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_cannot_step_breakpoint (gdbarch, 1);
/* Handles single stepping of atomic sequences. */
- set_gdbarch_software_single_step (gdbarch, alpha_deal_with_atomic_sequence);
+ set_gdbarch_software_single_step (gdbarch, alpha_software_single_step);
/* Hook in ABI-specific overrides, if they have been registered. */
gdbarch_init_osabi (info, gdbarch);
@@ -155,6 +155,8 @@ struct buffer;
Beginning with Linux 4.6, the MIPS port reports proper TRAP_BRKPT and
TRAP_HWBKPT codes, so we also match them.
+ The Alpha kernel uses TRAP_BRKPT for all traps.
+
The generic Linux target code should use GDB_ARCH_IS_TRAP_* instead
of TRAP_* to abstract out these peculiarities. */
#if defined __i386__ || defined __x86_64__
@@ -166,6 +168,9 @@ struct buffer;
#elif defined __mips__
# define GDB_ARCH_IS_TRAP_BRKPT(X) ((X) == SI_KERNEL || (X) == TRAP_BRKPT)
# define GDB_ARCH_IS_TRAP_HWBKPT(X) ((X) == SI_KERNEL || (X) == TRAP_HWBKPT)
+#elif defined __alpha__
+# define GDB_ARCH_IS_TRAP_BRKPT(X) ((X) == TRAP_BRKPT)
+# define GDB_ARCH_IS_TRAP_HWBKPT(X) ((X) == TRAP_BRKPT)
#else
# define GDB_ARCH_IS_TRAP_BRKPT(X) ((X) == TRAP_BRKPT)
# define GDB_ARCH_IS_TRAP_HWBKPT(X) ((X) == TRAP_HWBKPT)