[PATCH] IA64: EC, the Epilog Count register, is available in ptrace.

[Pedro Alves <palves@redhat.com>]

> gcore.exp failures related to these issues.  It shows the $f0/$f1 issue, and
> also, that $ec is read back from the core as 0, but it is read as
> *unavailable* when debugging a live process.  The latter is because
> have (ia64-linux-nat.c):
>
> static int u_offsets[] =
>   {
> ...
>     PT_AR_LC,
>     -1,		/* Not available: EC, the Epilog Count register.  */
>
> But in ia64-linux-nat.c:supply_gregset:
>
>   regcache_raw_supply (regcache, IA64_LC_REGNUM, regp + 53);
>   regcache_raw_supply (regcache, IA64_EC_REGNUM, regp + 54);
>
> which is suspicious (the registers is not retrievable with ptrace, but
> it's in the core?).  Indeed, on this system's /usr/include/asm/ptrace_offsets.h
> I see:
>
> #define PT_AR_EC                0x0800
> #define PT_AR_LC                0x0808
>
> So it does look like it is available with ptrace.

Git blame on the kernel's sources shows the define always existed for
at least as long as there's git history (1da177e, 2.6.12-rc2).  I
haven't checked further back...

WDYT?

2012-03-28  Pedro Alves  <palves@redhat.com>

	* ia64-linux-nat.c (u_offsets): Map IA64_EC_REGNUM to PT_AR_EC.
---
 gdb/ia64-linux-nat.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/gdb/ia64-linux-nat.c b/gdb/ia64-linux-nat.c
index 60b873b..24bde2d 100644
--- a/gdb/ia64-linux-nat.c
+++ b/gdb/ia64-linux-nat.c
@@ -272,7 +272,7 @@ static int u_offsets[] =
     -1, -1, -1, -1, -1, -1, -1, -1, -1,
     PT_AR_PFS,
     PT_AR_LC,
-    -1,		/* Not available: EC, the Epilog Count register.  */
+    PT_AR_EC,
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,