[PATCH v2 01/21] powerpc: Create stackframe information on syscall

[Adhemerval Zanella]

This patch adds a minimal stackframe creation on powerpc syscall
implementation so backtrace works correctly on a signal handler.

Checked on powerpc64le-linux-gnu.

	* sysdeps/unix/sysv/linux/powerpc/syscall.S (syscall): Create stack
	frame.
---
 ChangeLog                                 |  3 +++
 sysdeps/unix/sysv/linux/powerpc/syscall.S | 14 ++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S
index 2da9172..fae0fe8 100644
--- a/sysdeps/unix/sysv/linux/powerpc/syscall.S
+++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S
@@ -19,6 +19,14 @@
 
 ENTRY (syscall)
 	ABORT_TRANSACTION
+	/* Creates a minimum stack frame so backtrace works.  */
+#ifdef __powerpc64__
+	stdu r1, -FRAME_MIN_SIZE (r1)
+	cfi_adjust_cfa_offset (FRAME_MIN_SIZE)
+#else
+	stwu r1,-16(1)
+	cfi_def_cfa_offset (16)
+#endif
 	mr   r0,r3
 	mr   r3,r4
 	mr   r4,r5
@@ -26,6 +34,12 @@ ENTRY (syscall)
 	mr   r6,r7
 	mr   r7,r8
 	mr   r8,r9
+#ifdef __powerpc64__
+	addi r1, r1, FRAME_MIN_SIZE
+#else
+	addi r1,r1,16
+#endif
+	cfi_def_cfa_offset (0)
 	sc
 	PSEUDO_RET
 PSEUDO_END (syscall)
-- 
2.7.4