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[RFC 6/6] ARC: Fix several testsuite failures related to unwinding
- From: Vineet Gupta <Vineet dot Gupta1 at synopsys dot com>
- To: "libc-alpha @ sourceware . org" <libc-alpha at sourceware dot org>
- Cc: <linux-snps-arc at lists dot infradead dot org>, <Cupertino dot Miranda at synopsys dot com>, "Vineet Gupta" <Vineet dot Gupta1 at synopsys dot com>
- Date: Tue, 27 Jun 2017 11:00:54 +0300
- Subject: [RFC 6/6] ARC: Fix several testsuite failures related to unwinding
- Authentication-results: sourceware.org; auth=none
- References: <1498550454-3560-1-git-send-email-vgupta@synopsys.com>
From: Cupertino Miranda <cmiranda@synopsys.com>
1. Add BLINK clobber to syscall wrappers allowing unwinding off of
sleeping syscalls
(this is arguably excessive, give it is not needed except for a
handful of slow syscalls such as read/write/nanosleep...)
2. Rework sigreturn to undo above since we don't want BLINK spilled
on stack for this specific case
3. Add dwarf CFI psuedo-ops to various syscall generators
Signed-off-by: Cupertino Miranda <cmiranda@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
---
sysdeps/arc/dl-trampoline.S | 9 +++++++++
sysdeps/arc/sysdep.h | 2 ++
sysdeps/unix/sysv/linux/arc/sigaction.c | 7 ++++++-
sysdeps/unix/sysv/linux/arc/sysdep-cancel.h | 4 ++++
sysdeps/unix/sysv/linux/arc/sysdep.h | 12 ++++++++----
5 files changed, 29 insertions(+), 5 deletions(-)
diff --git a/sysdeps/arc/dl-trampoline.S b/sysdeps/arc/dl-trampoline.S
index 0e781af8380e..06fd7ff9a667 100644
--- a/sysdeps/arc/dl-trampoline.S
+++ b/sysdeps/arc/dl-trampoline.S
@@ -37,11 +37,16 @@
st.a r7, [sp, -4]
st.a r8, [sp, -4]
st.a r9, [sp, -4]
+ cfi_adjust_cfa_offset (40)
push_s blink
+ cfi_adjust_cfa_offset (4)
+ cfi_rel_offset (blink, 0)
.endm
.macro RESTORE_CALLER_SAVED_BUT_R0
ld.ab blink,[sp, 4]
+ cfi_adjust_cfa_offset (-4)
+ cfi_restore (blink)
ld.ab r9, [sp, 4]
ld.ab r8, [sp, 4]
ld.ab r7, [sp, 4]
@@ -51,6 +56,7 @@
pop_s r3
pop_s r2
pop_s r1
+ cfi_adjust_cfa_offset (-36)
.endm
; Upon entry, PLTn, which led us here, sets up the following regs
@@ -69,4 +75,7 @@ ENTRY(_dl_runtime_resolve)
RESTORE_CALLER_SAVED_BUT_R0
j_s.d [r0] ; r0 has resolved function addr
pop_s r0 ; restore first arg to resolved call
+ cfi_adjust_cfa_offset (-4)
+ cfi_restore (r0)
+
END(_dl_runtime_resolve)
diff --git a/sysdeps/arc/sysdep.h b/sysdeps/arc/sysdep.h
index d57f1c0c60a4..c4495bd877c9 100644
--- a/sysdeps/arc/sysdep.h
+++ b/sysdeps/arc/sysdep.h
@@ -32,10 +32,12 @@
.globl C_SYMBOL_NAME(name) ASM_LINE_SEP \
.type C_SYMBOL_NAME(name),%function ASM_LINE_SEP \
C_LABEL(name) ASM_LINE_SEP \
+ cfi_startproc ASM_LINE_SEP \
CALL_MCOUNT
#undef END
#define END(name) \
+ cfi_endproc ASM_LINE_SEP \
ASM_SIZE_DIRECTIVE(name)
#ifdef SHARED
diff --git a/sysdeps/unix/sysv/linux/arc/sigaction.c b/sysdeps/unix/sysv/linux/arc/sigaction.c
index 2bd7b0f08ddc..e2b898039df1 100644
--- a/sysdeps/unix/sysv/linux/arc/sigaction.c
+++ b/sysdeps/unix/sysv/linux/arc/sigaction.c
@@ -26,7 +26,12 @@
*/
static void __default_rt_sa_restorer(void)
{
- INTERNAL_SYSCALL_NCS(__NR_rt_sigreturn, , 0);
+ /* Don't use INTERNAL_SYSCALL_NCS as it causes blink to be spilled on stack */
+ asm volatile(
+ "mov r8, %0 \n\t" \
+ ARC_TRAP_INSN \
+ :
+ : "r"(__NR_rt_sigreturn));
}
#define SA_RESTORER 0x04000000
diff --git a/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h b/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h
index db89ad033a79..b2dbb8670874 100644
--- a/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h
+++ b/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h
@@ -83,10 +83,14 @@
.macro PUSH reg
st.a \reg, [sp, -4]
+ cfi_adjust_cfa_offset (4)
+ cfi_rel_offset (\reg, 0)
.endm
.macro POP reg
ld.ab \reg, [sp, 4]
+ cfi_adjust_cfa_offset (-4)
+ cfi_restore (\reg)
.endm
#define DOCARGS_0 PUSH blink
diff --git a/sysdeps/unix/sysv/linux/arc/sysdep.h b/sysdeps/unix/sysv/linux/arc/sysdep.h
index 507d06a8a575..492a709b51fd 100644
--- a/sysdeps/unix/sysv/linux/arc/sysdep.h
+++ b/sysdeps/unix/sysv/linux/arc/sysdep.h
@@ -103,8 +103,12 @@
# define SYSCALL_ERROR_HANDLER \
0: ASM_LINE_SEP \
st.a blink, [sp, -4] ASM_LINE_SEP \
+ cfi_adjust_cfa_offset (4) ASM_LINE_SEP \
+ cfi_rel_offset (blink, 0) ASM_LINE_SEP \
CALL_ERRNO_SETTER_C ASM_LINE_SEP \
ld.ab blink, [sp, 4] ASM_LINE_SEP \
+ cfi_adjust_cfa_offset (-4) ASM_LINE_SEP \
+ cfi_restore (blink) ASM_LINE_SEP \
j [blink]
# define DO_CALL(syscall_name, args) \
@@ -137,13 +141,13 @@ hidden_proto (__syscall_error)
__res = INTERNAL_SYSCALL_NCS(__NR_##name, , nr_args, args); \
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P ((__res), ), 0)) \
{ \
- asm volatile ("st.a blink, [sp, -4] \n\t" \
+ asm volatile ( \
CALL_ERRNO_SETTER \
- "ld.ab blink, [sp, 4] \n\t" \
:"+r" (__res) \
: \
:"r1","r2","r3","r4","r5","r6", \
- "r7","r8","r9","r10","r11","r12"); \
+ "r7","r8","r9","r10","r11","r12", \
+ "blink"); \
} \
__res; \
})
@@ -174,7 +178,7 @@ hidden_proto (__syscall_error)
ARC_TRAP_INSN \
: "+r" (__ret) \
: "r"(_sys_num) ASM_ARGS_##nr_args \
- : "memory"); \
+ : "memory", "blink"); \
\
__ret; \
})
--
2.7.4