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Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/arm/nptl/vfork.S')
-rw-r--r--ports/sysdeps/unix/sysv/linux/arm/nptl/vfork.S42
1 files changed, 42 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/arm/nptl/vfork.S b/ports/sysdeps/unix/sysv/linux/arm/nptl/vfork.S
new file mode 100644
index 0000000000..235380198b
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/arm/nptl/vfork.S
@@ -0,0 +1,42 @@
+/* Copyright (C) 2005, 2010 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <tcb-offsets.h>
+
+/* Save the PID value. */
+#define SAVE_PID \
+ str lr, [sp, #-4]!; /* Save LR. */ \
+ cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (lr, 0); \
+ mov r0, #0xffff0fff; /* Point to the high page. */ \
+ mov lr, pc; /* Save our return address. */ \
+ sub pc, r0, #31; /* Jump to the TLS entry. */ \
+ ldr lr, [sp], #4; /* Restore LR. */ \
+ cfi_adjust_cfa_offset (-4); \
+ cfi_restore (lr); \
+ mov r2, r0; /* Save the TLS addr in r2. */ \
+ ldr r3, [r2, #PID_OFFSET]; /* Load the saved PID. */ \
+ rsbs r0, r3, #0; /* Negate it. */ \
+ moveq r0, #0x80000000; /* Use 0x80000000 if it was 0. */ \
+ str r0, [r2, #PID_OFFSET] /* Store the temporary PID. */
+
+/* Restore the old PID value in the parent. */
+#define RESTORE_PID \
+ cmp r0, #0; /* If we are the parent... */ \
+ strne r3, [r2, #PID_OFFSET] /* ... restore the saved PID. */
+
+#include "../vfork.S"