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Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/arm/setcontext.S')
-rw-r--r--ports/sysdeps/unix/sysv/linux/arm/setcontext.S101
1 files changed, 101 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/arm/setcontext.S b/ports/sysdeps/unix/sysv/linux/arm/setcontext.S
new file mode 100644
index 0000000000..d163fc4a4c
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/arm/setcontext.S
@@ -0,0 +1,101 @@
+/* Copyright (C) 2012 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 <sysdep.h>
+#include <rtld-global-offsets.h>
+
+#include "ucontext_i.h"
+
+ .syntax unified
+ .text
+
+/* int setcontext (const ucontext_t *ucp) */
+
+ENTRY(__setcontext)
+ mov r4, r0
+ add r0, r0, #UCONTEXT_REGSPACE
+
+ /* Restore the VFP registers. Copied from arm/__longjmp.S. */
+#ifdef PIC
+ ldr r2, 1f
+ ldr r1, Lrtld_global_ro
+0: add r2, pc, r2
+ ldr r2, [r2, r1]
+ ldr r2, [r2, #RTLD_GLOBAL_RO_DL_HWCAP_OFFSET]
+#else
+ ldr r2, Lhwcap
+ ldr r2, [r2, #0]
+#endif
+
+ tst r2, #HWCAP_ARM_VFP
+ beq Lno_vfp_sc
+
+ /* Following instruction is vldmia r0!, {d8-d15}. */
+ ldc p11, cr8, [r0], #64
+ /* Restore the floating-point status register. */
+ ldr r1, [r0], #4
+ /* Following instruction is fmxr fpscr, r1. */
+ mcr p10, 7, r1, cr1, cr0, 0
+Lno_vfp_sc:
+ tst r2, #HWCAP_ARM_IWMMXT
+ beq Lno_iwmmxt_sc
+
+ /* Restore the call-preserved iWMMXt registers. */
+ /* Following instructions are wldrd wr10, [r0], #8 (etc.) */
+ ldcl p1, cr10, [r0], #8
+ ldcl p1, cr11, [r0], #8
+ ldcl p1, cr12, [r0], #8
+ ldcl p1, cr13, [r0], #8
+ ldcl p1, cr14, [r0], #8
+ ldcl p1, cr15, [r0], #8
+Lno_iwmmxt_sc:
+
+ /* Now bring back the signal status. */
+ mov r0, #SIG_SETMASK
+ add r1, r4, #UCONTEXT_SIGMASK
+ mov r2, #0
+ bl PLTJMP(__sigprocmask)
+
+ /* Loading r0-r3 makes makecontext easier. */
+ add r14, r4, #MCONTEXT_ARM_R0
+ ldmia r14, {r0-r12}
+ ldr r13, [r14, #(MCONTEXT_ARM_SP - MCONTEXT_ARM_R0)]
+ add r14, r14, #(MCONTEXT_ARM_LR - MCONTEXT_ARM_R0)
+ ldmia r14, {r14, pc}
+
+END(setcontext)
+weak_alias(__setcontext, setcontext)
+
+ /* Called when a makecontext() context returns. Start the
+ context in R4 or fall through to exit(). */
+ENTRY(__startcontext)
+ movs r0, r4
+ bne PLTJMP(__setcontext)
+
+ @ New context was 0 - exit
+ b PLTJMP(HIDDEN_JUMPTARGET(_exit))
+END(__startcontext)
+
+#ifdef PIC
+1: .long _GLOBAL_OFFSET_TABLE_ - 0b - 8
+Lrtld_global_ro:
+ .long C_SYMBOL_NAME(_rtld_global_ro)(GOT)
+#else
+Lhwcap:
+ .long C_SYMBOL_NAME(_dl_hwcap)
+#endif
+