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-rw-r--r--sysdeps/unix/sysv/linux/arm/setcontext.S104
1 files changed, 104 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/arm/setcontext.S b/sysdeps/unix/sysv/linux/arm/setcontext.S
new file mode 100644
index 0000000000..7b9b511b80
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/arm/setcontext.S
@@ -0,0 +1,104 @@
+/* Copyright (C) 2012-2014 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/>.  */
+
+/* ??? Needs more rearrangement for the LDM to handle thumb mode.  */
+#define NO_THUMB
+#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
+
+#ifdef __SOFTFP__
+	tst     r2, #HWCAP_ARM_VFP
+	beq     .Lno_vfp_sc
+#endif
+
+	/* 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 - PC_OFS
+.Lrtld_global_ro:
+	.long   C_SYMBOL_NAME(_rtld_global_ro)(GOT)
+#else
+.Lhwcap:
+	.long   C_SYMBOL_NAME(_dl_hwcap)
+#endif