[PATCH v3 4/5] Refactor the breakpoint definitions in linux-arm-low.c.

Antoine Tremblay
2015-10-20T16:48:22Z

Before arm_breakpoint_from_pc would use an #ifdef to return the right
arm_breakpoint from the abi or eabi breakpoint type.

arm_breakpoint_at would also check for the arm_breakpoint ||
arm_eabi_breakpoint.

Thus the selected arm_breakpoint would be what arm_breakpoint_from_pc returned
and arm_breakpoint was arm_abi_breakpoint.

This patch makes it more clear by naming those for what they are : 2 separate
entities: arm_abi_breakpoint and arm_eabi_breakpoint and set the current used
one as arm_breakpoint.

This allows a cleaner arm_breakpoint_from_pc as it just returns arm_breakpoint
rather than having the #ifdef in that function.

Any other reference to the arm_breakpoint can now also be clear of #ifdefs...

No regressions on Ubuntu 14.04 on ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:
* linux-arm-low.c: Refactor breakpoint definitions.
(arm_breakpoint_at): Adjust for arm_abi_breakpoint.
(arm_breakpoint_from_pc): Adjust for arm_breakpoint.
---
gdb/gdbserver/linux-arm-low.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/gdb/gdbserver/linux-arm-low.c b/gdb/gdbserver/linux-arm-low.c
index 9b0975f..62e88f0 100644
--- a/gdb/gdbserver/linux-arm-low.c
+++ b/gdb/gdbserver/linux-arm-low.c
@@ -244,18 +244,25 @@ arm_set_pc (struct regcache *regcache, CORE_ADDR pc)
}

/* Correct in either endianness. */
-static const unsigned long arm_breakpoint = 0xef9f0001;
-#define arm_breakpoint_len 4
-static const unsigned short thumb_breakpoint = 0xde01;
-#define thumb_breakpoint_len 2
-static const unsigned short thumb2_breakpoint[] = { 0xf7f0, 0xa000 };
-#define thumb2_breakpoint_len 4
+#define arm_abi_breakpoint 0xef9f0001UL

/* For new EABI binaries. We recognize it regardless of which ABI
is used for gdbserver, so single threaded debugging should work
OK, but for multi-threaded debugging we only insert the current
ABI's breakpoint instruction. For now at least. */
-static const unsigned long arm_eabi_breakpoint = 0xe7f001f0;
+#define arm_eabi_breakpoint 0xe7f001f0UL
+
+#ifndef __ARM_EABI__
+static const unsigned long arm_breakpoint = arm_abi_breakpoint;
+#else
+static const unsigned long arm_breakpoint = arm_eabi_breakpoint;
+#endif
+
+#define arm_breakpoint_len 4
+static const unsigned short thumb_breakpoint = 0xde01;
+#define thumb_breakpoint_len 2
+static const unsigned short thumb2_breakpoint[] = { 0xf7f0, 0xa000 };
+#define thumb2_breakpoint_len 4

static int
arm_breakpoint_at (CORE_ADDR where)
@@ -287,7 +294,7 @@ arm_breakpoint_at (CORE_ADDR where)
unsigned long insn;

(*the_target->read_memory) (where, (unsigned char *) &insn, 4);
- if (insn == arm_breakpoint)
+ if (insn == arm_abi_breakpoint)
return 1;

if (insn == arm_eabi_breakpoint)
@@ -982,11 +989,7 @@ arm_sw_breakpoint_from_kind (int kind , int *size)
return (gdb_byte *) &thumb2_breakpoint;
case ARM_BP_KIND_ARM:
*size = arm_breakpoint_len;
-#ifndef __ARM_EABI__
return (const gdb_byte *) &arm_breakpoint;
-#else
- return (const gdb_byte *) &arm_eabi_breakpoint;
-#endif
default:
return NULL;
}
--
1.9.1