C-SKY: mark lr as undefined to stop unwinding

Mark the lr register as undefined at the start of execution, so unwind
will stop at this frame. run-backtrace-*.sh from elfutils testsuite will
fail without this patch.

	* sysdeps/csky/abiv2/start.S: Mark lr as undefined.
	* sysdeps/unix/sysv/linux/csky/abiv2/clone.S: Likewise.
	* sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S: Likewise.

diff --git a/ChangeLog b/ChangeLog
index 850e638..2f47cb8 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2019-03-11  Mao Han  <han_mao@c-sky.com>
 
+       * sysdeps/csky/abiv2/start.S: Mark lr as undefined.
+       * sysdeps/unix/sysv/linux/csky/abiv2/clone.S: Likewise.
+       * sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S: Likewise.
+
+2019-03-11  Mao Han  <han_mao@c-sky.com>
+
        * sysdeps/unix/sysv/linux/csky/sys/procfs.h: Use linux definition
        directly.
        * sysdeps/unix/sysv/linux/csky/sys/user.h: Remove user_regs

diff --git a/sysdeps/csky/abiv2/start.S b/sysdeps/csky/abiv2/start.S
index 324ed69..b1e6152 100644 (file)
--- a/sysdeps/csky/abiv2/start.S
+++ b/sysdeps/csky/abiv2/start.S
@@ -46,6 +46,9 @@
        .type _start,@function;
        .align 4;
 _start:
+       cfi_startproc
+       .cfi_label .Ldummy
+       cfi_undefined (lr)
        subi    sp, 8
        /* Clear the link register since this is the outermost frame.  */
        movi    lr, 0
@@ -96,6 +99,7 @@ _start:
        /* Should never get here.  */
        jsri    abort
 #endif /* !SHARED */
+       cfi_endproc
        .size _start,.-_start
 
 

diff --git a/sysdeps/unix/sysv/linux/csky/abiv2/clone.S b/sysdeps/unix/sysv/linux/csky/abiv2/clone.S
index 3e7328a..c1352ee 100644 (file)
--- a/sysdeps/unix/sysv/linux/csky/abiv2/clone.S
+++ b/sysdeps/unix/sysv/linux/csky/abiv2/clone.S
@@ -54,7 +54,7 @@ ENTRY (__clone)
        btsti   a0, 31          /* Check if return is less than zero.  */
        bt      __do_syscall_error
        cmpnei  a0, 0
-       bf      __child
+       bf      __thread_start
        rts
 
 __error_arg:
@@ -81,7 +81,9 @@ __do_syscall_error:
        rts
 PSEUDO_END (__clone)
 
-__child:
+ENTRY (__thread_start)
+       .cfi_label .Ldummy
+       cfi_undefined (lr)
        ldw     a0, (sp, 4)     /* Restore args from new sp.  */
        ldw     a1, (sp, 0)     /* Restore function from new sp.  */
        addi    sp, 8
@@ -90,6 +92,7 @@ __child:
        /* exit */
        lrw     r7, __NR_exit
        trap    0
+END (__thread_start)
 
 libc_hidden_def (__clone)
 weak_alias (__clone, clone)

diff --git a/sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S b/sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S
index 6d3f04f..34de6e3 100644 (file)
--- a/sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S
+++ b/sysdeps/unix/sysv/linux/csky/abiv2/setcontext.S
@@ -62,6 +62,8 @@ END (setcontext)
 weak_alias (__setcontext, setcontext)
 
 ENTRY (__startcontext)
+       .cfi_label .Ldummy
+       cfi_undefined (lr)
        mov     a0, r9
        cmpnei  r9, 0   /* r9 was set in makecontext.  */
        bf      1f      /* null, then exit.  */