diff options
Diffstat (limited to 'libc/sysdeps/linux/mips/makecontext.S')
| -rw-r--r-- | libc/sysdeps/linux/mips/makecontext.S | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/mips/makecontext.S b/libc/sysdeps/linux/mips/makecontext.S new file mode 100644 index 000000000..6427339a6 --- /dev/null +++ b/libc/sysdeps/linux/mips/makecontext.S @@ -0,0 +1,188 @@ +/* Modify saved context. + Copyright (C) 2009 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Maciej W. Rozycki <macro@codesourcery.com>. + + 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 <sys/asm.h> +#include <sys/fpregdef.h> +#include <sys/regdef.h> + +#include "ucontext_i.h" + +/* int makecontext (ucontext_t *ucp, (void *func) (), int argc, ...) */ + + .text +LOCALSZ = 0 +ARGSZ = 0 +MASK = 0x00000000 +#ifdef __PIC__ +LOCALSZ = 1 /* save gp */ +#endif +#if _MIPS_SIM != _ABIO32 +ARGSZ = 5 /* save a3-a7 */ +# ifdef __PIC__ +MASK = 0x10000000 +# endif +#endif +FRAMESZ = (((ARGSZ + LOCALSZ) * SZREG) + ALSZ) & ALMASK +GPOFF = FRAMESZ - ((ARGSZ + 1) * SZREG) +#if _MIPS_SIM != _ABIO32 +A3OFF = FRAMESZ - (5 * SZREG) /* callee-allocated */ +A4OFF = FRAMESZ - (4 * SZREG) +A5OFF = FRAMESZ - (3 * SZREG) +A6OFF = FRAMESZ - (2 * SZREG) +A7OFF = FRAMESZ - (1 * SZREG) +NARGREGS = 8 +#else +A3OFF = FRAMESZ + (3 * SZREG) /* caller-allocated */ +NARGREGS = 4 +#endif + +NESTED (__makecontext, FRAMESZ, ra) + .mask MASK, -(ARGSZ * SZREG) + .fmask 0x00000000, 0 + +98: +#ifdef __PIC__ + SETUP_GP +#endif + + PTR_ADDIU sp, -FRAMESZ + +#ifdef __PIC__ + SETUP_GP64 (GPOFF, __makecontext) + SAVE_GP (GPOFF) +#endif + +#ifdef PROF + .set noat + move AT, ra + jal _mcount + .set at +#endif + + /* Store args to be passed. */ + REG_S a3, A3OFF(sp) +#if _MIPS_SIM != _ABIO32 + REG_S a4, A4OFF(sp) + REG_S a5, A5OFF(sp) + REG_S a6, A6OFF(sp) + REG_S a7, A7OFF(sp) +#endif + + /* Store a magic flag. */ + li v1, 1 + REG_S v1, (0 * SZREG + MCONTEXT_GREGS)(a0) /* zero */ + + /* Set up the stack. */ + PTR_L t0, STACK_SP(a0) + PTR_L t2, STACK_SIZE(a0) + PTR_ADDIU t1, sp, A3OFF + PTR_ADDU t0, t2 + and t0, ALMASK + blez a2, 2f /* no arguments */ + + /* Store register arguments. */ + PTR_ADDIU t2, a0, MCONTEXT_GREGS + 4 * SZREG + move t3, zero +0: + addiu t3, 1 + REG_L v1, (t1) + PTR_ADDIU t1, SZREG + REG_S v1, (t2) + PTR_ADDIU t2, SZREG + bgeu t3, a2, 2f /* all done */ + bltu t3, NARGREGS, 0b /* next */ + + /* Make room for stack arguments. */ + PTR_SUBU t2, a2, t3 + PTR_SLL t2, 3 + PTR_SUBU t0, t2 + and t0, ALMASK + + /* Store stack arguments. */ + move t2, t0 +1: + addiu t3, 1 + REG_L v1, (t1) + PTR_ADDIU t1, SZREG + REG_S v1, (t2) + PTR_ADDIU t2, SZREG + bltu t3, a2, 1b /* next */ + +2: +#if _MIPS_SIM == _ABIO32 + /* Make room for a0-a3 storage. */ + PTR_ADDIU t0, -(NARGSAVE * SZREG) +#endif + PTR_L v1, UCONTEXT_LINK(a0) +#ifdef __PIC__ + PTR_ADDIU t9, 99f - 98b +#else + PTR_LA t9, 99f +#endif + REG_S t0, (29 * SZREG + MCONTEXT_GREGS)(a0) /* sp */ + REG_S v1, (16 * SZREG + MCONTEXT_GREGS)(a0) /* s0 */ +#ifdef __PIC__ + REG_S gp, (17 * SZREG + MCONTEXT_GREGS)(a0) /* s1 */ +#endif + REG_S t9, (31 * SZREG + MCONTEXT_GREGS)(a0) /* ra */ + REG_S a1, MCONTEXT_PC(a0) + +#ifdef __PIC__ + RESTORE_GP64 + PTR_ADDIU sp, FRAMESZ +#endif + jr ra + +99: +#ifdef __PIC__ + move gp, s1 +#endif + move a0, zero + beqz s0, 0f + + /* setcontext (ucp) */ + move a0, s0 +#ifdef __PIC__ + PTR_LA t9, JUMPTARGET (__setcontext) + jalr t9 +# if _MIPS_SIM == _ABIO32 + move gp, s1 +# endif +#else + jal JUMPTARGET (__setcontext) +#endif + move a0, v0 + +0: + /* exit (a0) */ +#ifdef __PIC__ + PTR_LA t9, HIDDEN_JUMPTARGET (exit) + jalr t9 +#else + jal HIDDEN_JUMPTARGET (exit) +#endif + + /* You don't exist, you won't feel anything. */ +1: + lb zero, (zero) + b 1b +PSEUDO_END (__makecontext) + +weak_alias (__makecontext, makecontext) |