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authorRichard Henderson <rth@redhat.com>2014-05-25 14:57:53 -0400
committerRichard Henderson <rth@redhat.com>2014-05-29 12:37:24 -0400
commitb5be4597716eff94149f5529c8eb2cd3b4296188 (patch)
tree70bacc7639c71fea51ace01baee640ce3fd6e8df
parent645d44abe3ca6253a9d4762f092e4a1b9d294b11 (diff)
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aarch64: Improve syscall-cancel stack frame
One push instead of N; use stp/ldp to halve the insns.
-rw-r--r--ChangeLog10
-rw-r--r--sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h112
2 files changed, 36 insertions, 86 deletions
diff --git a/ChangeLog b/ChangeLog
index 3a20a65..26812de 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
2014-05-29 Richard Henderson <rth@twiddle.net>
+ * sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h (PSEUDO):
+ Always allocate 64 bytes of stack frame. Use ldp/stp to create
+ it and break it down.
+ (DOCARGS_0, DOCARGS_1): Do nothing.
+ (DOCARGS_2): Update to store into the new stack frame.
+ (DOCARGS_3, DOCARGS_4, DOCARGS_5, DOCARGS_6): Likewise.
+ (UNDOCARGS_1): Update to restore from the new stack frame.
+ (UNDOCARGS_2, UNDOCARGS_3, UNDOCARGS_4): Likewise.
+ (UNDOCARGS_5, UNDOCARGS_6): Likewise.
+
* sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h
(SINGLE_THREAD_P): New parameter for result regno.
(PSEUDO): Update to match; use cbz instead of beq.
diff --git a/sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h b/sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h
index bdb5c73..0f5bb51 100644
--- a/sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h
+++ b/sysdeps/unix/sysv/linux/aarch64/nptl/sysdep-cancel.h
@@ -38,20 +38,22 @@ ENTRY (__##syscall_name##_nocancel); \
ENTRY (name); \
SINGLE_THREAD_P(16); \
cbz w16, .Lpseudo_nocancel; \
- DOCARGS_##args; /* save syscall args etc. around CENABLE. */ \
+ /* Setup common stack frame no matter the number of args. \
+ Also save the first arg, since it's basically free. */ \
+ stp x30, x0, [sp, -64]!; \
+ cfi_adjust_cfa_offset (64); \
+ cfi_rel_offset (x30, 0); \
+ DOCARGS_##args; /* save syscall args around CENABLE. */ \
CENABLE; \
- mov x16, x0; /* put mask in safe place. */ \
+ mov x16, x0; /* save mask around syscall. */ \
UNDOCARGS_##args; /* restore syscall args. */ \
- mov x8, SYS_ify (syscall_name); /* do the call. */ \
- svc 0; \
- str x0, [sp, -16]!; /* save syscall return value. */ \
- cfi_adjust_cfa_offset (16); \
- mov x0, x16; /* get mask back. */ \
+ DO_CALL (syscall_name, args); \
+ str x0, [sp, 8]; /* save result around CDISABLE. */ \
+ mov x0, x16; /* restore mask for CDISABLE. */ \
CDISABLE; \
- ldr x0, [sp], 16; \
- cfi_adjust_cfa_offset (-16); \
- ldr x30, [sp], 16; \
- cfi_adjust_cfa_offset (-16); \
+ /* Break down the stack frame, restoring result at once. */ \
+ ldp x30, x0, [sp], 64; \
+ cfi_adjust_cfa_offset (-64); \
cfi_restore (x30); \
b .Lpseudo_finish; \
cfi_endproc; \
@@ -63,83 +65,21 @@ ENTRY (name); \
SYSCALL_ERROR_HANDLER; \
cfi_endproc
-# define DOCARGS_0 \
- str x30, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x30, 0)
+# define DOCARGS_0
+# define DOCARGS_1
+# define DOCARGS_2 str x1, [sp, 16]
+# define DOCARGS_3 stp x1, x2, [sp, 16]
+# define DOCARGS_4 DOCARGS_3; str x3, [sp, 32]
+# define DOCARGS_5 DOCARGS_3; stp x3, x4, [sp, 32]
+# define DOCARGS_6 DOCARGS_5; str x5, [sp, 48]
# define UNDOCARGS_0
-
-# define DOCARGS_1 \
- DOCARGS_0; \
- str x0, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x0, 0)
-
-# define UNDOCARGS_1 \
- ldr x0, [sp], 16; \
- cfi_restore (x0); \
- cfi_adjust_cfa_offset (-16); \
-
-# define DOCARGS_2 \
- DOCARGS_1; \
- str x1, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x1, 0)
-
-# define UNDOCARGS_2 \
- ldr x1, [sp], 16; \
- cfi_restore (x1); \
- cfi_adjust_cfa_offset (-16); \
- UNDOCARGS_1
-
-# define DOCARGS_3 \
- DOCARGS_2; \
- str x2, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x2, 0)
-
-# define UNDOCARGS_3 \
- ldr x2, [sp], 16; \
- cfi_restore (x2); \
- cfi_adjust_cfa_offset (-16); \
- UNDOCARGS_2
-
-# define DOCARGS_4 \
- DOCARGS_3; \
- str x3, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x3, 0)
-
-# define UNDOCARGS_4 \
- ldr x3, [sp], 16; \
- cfi_restore (x3); \
- cfi_adjust_cfa_offset (-16); \
- UNDOCARGS_3
-
-# define DOCARGS_5 \
- DOCARGS_4; \
- str x4, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x4, 0)
-
-# define UNDOCARGS_5 \
- ldr x4, [sp], 16; \
- cfi_restore (x4); \
- cfi_adjust_cfa_offset (-16); \
- UNDOCARGS_4
-
-# define DOCARGS_6 \
- DOCARGS_5; \
- str x5, [sp, -16]!; \
- cfi_adjust_cfa_offset (16); \
- cfi_rel_offset (x5, 0)
-
-# define UNDOCARGS_6 \
- ldr x5, [sp], 16; \
- cfi_restore (x5); \
- cfi_adjust_cfa_offset (-16); \
- UNDOCARGS_5
+# define UNDOCARGS_1 ldr x0, [sp, 8]
+# define UNDOCARGS_2 ldp x0, x1, [sp, 8]
+# define UNDOCARGS_3 UNDOCARGS_1; ldp x1, x2, [sp, 16]
+# define UNDOCARGS_4 UNDOCARGS_2; ldp x2, x3, [sp, 24]
+# define UNDOCARGS_5 UNDOCARGS_3; ldp x3, x4, [sp, 32]
+# define UNDOCARGS_6 UNDOCARGS_4; ldp x4, x5, [sp, 40]
# ifdef IS_IN_libpthread
# define CENABLE bl __pthread_enable_asynccancel