[v2,6/7] Refactor the breakpoint definitions in linux-arm-low.c.

Message ID 1444063455-31558-7-git-send-email-antoine.tremblay@ericsson.com
State New, archived
Headers

Commit Message

Antoine Tremblay Oct. 5, 2015, 4:44 p.m. UTC
  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(-)
  

Comments

Pedro Alves Oct. 15, 2015, 4:07 p.m. UTC | #1
On 10/05/2015 05:44 PM, Antoine Tremblay wrote:
> 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 8f420f9..d16ea60 100644
> --- a/gdb/gdbserver/linux-arm-low.c
> +++ b/gdb/gdbserver/linux-arm-low.c
> @@ -236,18 +236,25 @@ 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)
> @@ -279,7 +286,7 @@ 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)
> @@ -325,11 +332,7 @@ arm_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
>    else
>      {
>        *lenptr = arm_breakpoint_len;
> -#ifndef __ARM_EABI__
>        return (const unsigned char *) &arm_breakpoint;
> -#else
> -      return (const unsigned char *) &arm_eabi_breakpoint;
> -#endif
>      }
>  }
>  
> 

LGTM.  (Thought please collect an ack from Yao as well.)

Thanks,
Pedro Alves
  
Yao Qi Oct. 16, 2015, 11:45 a.m. UTC | #2
Pedro Alves <palves@redhat.com> writes:

> LGTM.  (Thought please collect an ack from Yao as well.)

Looks good to me too.
  

Patch

diff --git a/gdb/gdbserver/linux-arm-low.c b/gdb/gdbserver/linux-arm-low.c
index 8f420f9..d16ea60 100644
--- a/gdb/gdbserver/linux-arm-low.c
+++ b/gdb/gdbserver/linux-arm-low.c
@@ -236,18 +236,25 @@  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)
@@ -279,7 +286,7 @@  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)
@@ -325,11 +332,7 @@  arm_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
   else
     {
       *lenptr = arm_breakpoint_len;
-#ifndef __ARM_EABI__
       return (const unsigned char *) &arm_breakpoint;
-#else
-      return (const unsigned char *) &arm_eabi_breakpoint;
-#endif
     }
 }