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authorWaldemar Brodkorb <wbx@uclibc-ng.org>2016-04-23 12:17:56 +0200
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2016-04-26 19:41:08 +0200
commit2b3cdadee36b0445ed799932358dd94a1e839b46 (patch)
tree88120c5bcbf0a5420b3407bc5b0ccc1f0eae1456 /libc/sysdeps/linux/sparc/setcontext.S
parentf1dcb9beedc5d05238e90cfbad026736d6efe891 (diff)
sparc: add deprecated context switching functions
Ported over from glibc mostly without changes. Lightly tested with mongrel2 in qemu-system-sparc.
Diffstat (limited to 'libc/sysdeps/linux/sparc/setcontext.S')
-rw-r--r--libc/sysdeps/linux/sparc/setcontext.S118
1 files changed, 118 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/sparc/setcontext.S b/libc/sysdeps/linux/sparc/setcontext.S
new file mode 100644
index 000000000..f9da21563
--- /dev/null
+++ b/libc/sysdeps/linux/sparc/setcontext.S
@@ -0,0 +1,118 @@
+/* Install given context.
+ Copyright (C) 2008-2016 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by David S. Miller <davem@davemloft.net>, 2008.
+
+ 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 "ucontext_i.h"
+
+#define ST_FLUSH_WINDOWS 3
+
+/* int __setcontext (const ucontext_t *ucp)
+
+ Restores the machine context in UCP and thereby resumes execution
+ in that context.
+
+ This implementation is intended to be used for *synchronous* context
+ switches only. Therefore, it does not have to restore anything
+ other than the PRESERVED state. */
+
+ENTRY(__setcontext)
+ save %sp, -112, %sp
+
+ mov SIG_SETMASK, %o0
+ add %i0, UC_SIGMASK, %o1
+ clr %o2
+ mov 8, %o3
+ mov __NR_rt_sigprocmask, %g1
+ ta 0x10
+
+ /* This is a bit on the expensive side, and we could optimize
+ the unwind similar to how the 32-bit sparc longjmp code
+ does if performance of this routine really matters. */
+ ta ST_FLUSH_WINDOWS
+
+ ldub [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_EN], %g1
+ cmp %g1, 0
+ be 1f
+ nop
+ ld [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_FSR], %fsr
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D0], %f0
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D2], %f2
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D4], %f4
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D6], %f6
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D8], %f8
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D10], %f10
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D12], %f12
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D14], %f14
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D16], %f16
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D18], %f18
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D20], %f20
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D22], %f22
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D24], %f24
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D26], %f26
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D28], %f28
+ ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D30], %f30
+1:
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_Y], %g1
+ wr %g1, 0x0, %y
+
+ /* We specifically do not restore %g1 since we need it here as
+ a temporary. */
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G2], %g2
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G3], %g3
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G4], %g4
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G5], %g5
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G6], %g6
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G7], %g7
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O1], %i1
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O2], %i2
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O3], %i3
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O4], %i4
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O5], %i5
+ ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O6], %i6
+ restore
+ ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O7], %o7
+ ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_PC], %g1
+ jmpl %g1, %g0
+ ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O0], %o0
+END(__setcontext)
+
+weak_alias (__setcontext, setcontext)
+
+/* This is the helper code which gets called if a function which is
+ registered with 'makecontext' returns. In this case we have to
+ install the context listed in the uc_link element of the context
+ 'makecontext' manipulated at the time of the 'makecontext' call.
+ If the pointer is NULL the process must terminate. */
+
+ENTRY(__start_context)
+ ld [%sp + (16 * 4)], %g1
+ cmp %g1, 0
+ be,a 1f
+ clr %o0
+ call __setcontext
+ mov %g1, %o0
+ /* If this returns (which can happen if the syscall fails) we'll
+ exit the program with the return error value (-1). */
+1: call HIDDEN_JUMPTARGET(exit)
+ nop
+ /* The 'exit' call should never return. In case it does cause
+ the process to terminate. */
+ unimp
+END(__start_context)