genode/base-pistachio/patches/syscall_edi_clobber.patch
Christian Prochaska 7f7c24fcc9 Pistachio: tell the compiler about 'edi' changes
Syscall binding functions which use '__L4_INDIRECT_CALL' need to tell the
compiler that the 'edi' register gets modified. Since 'edi' is an input
operand and input operands may not get added to the clobber list, this
patch defines 'edi' also as an output operand instead.

Fixes #834.
2013-08-15 09:22:49 +02:00

55 lines
1.5 KiB
Diff

Tell the compiler about 'edi' register changes
From: Christian Prochaska <christian.prochaska@genode-labs.com>
Syscall binding functions which use '__L4_INDIRECT_CALL' need to tell the
compiler that the 'edi' register gets modified. Since 'edi' is an input
operand and input operands may not get added to the clobber list, this
patch defines 'edi' also as an output operand instead.
---
user/include/l4/ia32/syscalls.h | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/user/include/l4/ia32/syscalls.h b/user/include/l4/ia32/syscalls.h
index a1d6caa..1088d63 100644
--- a/user/include/l4/ia32/syscalls.h
+++ b/user/include/l4/ia32/syscalls.h
@@ -295,6 +295,7 @@ L4_INLINE L4_MsgTag_t L4_Ipc (L4_ThreadId_t to,
L4_Word_t * utcb = __L4_X86_Utcb ();
#if defined(__pic__)
+ L4_Word_t dummy;
__L4_Indirect_t in;
in.edi = (L4_Word_t)utcb;
in.sys_call = __L4_Ipc;
@@ -311,8 +312,9 @@ L4_INLINE L4_MsgTag_t L4_Ipc (L4_ThreadId_t to,
"=S" (mr0),
"=a" (result),
"=d" (mr1),
- "=c" (mr2)
-
+ "=c" (mr2),
+ "=D" (dummy)
+
: /* inputs */
"S" (utcb[0]),
"a" (to.raw),
@@ -370,6 +372,7 @@ L4_INLINE L4_MsgTag_t L4_Lipc (L4_ThreadId_t to,
#if defined(__pic__)
+ L4_Word_t dummy;
__L4_Indirect_t in;
in.edi = (L4_Word_t)utcb;
in.sys_call = __L4_Lipc;
@@ -386,7 +389,8 @@ L4_INLINE L4_MsgTag_t L4_Lipc (L4_ThreadId_t to,
"=S" (mr0),
"=a" (result),
"=d" (mr1),
- "=c" (mr2)
+ "=c" (mr2),
+ "=D" (dummy)
: /* inputs */
"S" (utcb[0]),