diff options
Diffstat (limited to 'gcc-4.9/libgcc/config/rl78/trampoline.S')
| -rw-r--r-- | gcc-4.9/libgcc/config/rl78/trampoline.S | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/gcc-4.9/libgcc/config/rl78/trampoline.S b/gcc-4.9/libgcc/config/rl78/trampoline.S new file mode 100644 index 000000000..410a83e6e --- /dev/null +++ b/gcc-4.9/libgcc/config/rl78/trampoline.S @@ -0,0 +1,136 @@ +/* libgcc routines for RL78 + Copyright (C) 2011-2014 Free Software Foundation, Inc. + Contributed by Red Hat. + + This file is part of GCC. + + GCC is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published + by the Free Software Foundation; either version 3, or (at your + option) any later version. + + GCC 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 General Public + License for more details. + + Under Section 7 of GPL version 3, you are granted additional + permissions described in the GCC Runtime Library Exception, version + 3.1, as published by the Free Software Foundation. + + You should have received a copy of the GNU General Public License and + a copy of the GCC Runtime Library Exception along with this program; + see the files COPYING3 and COPYING.RUNTIME respectively. If not, see + <http://www.gnu.org/licenses/>. */ + +/* RL78 Trampoline support + + Since the RL78's RAM is not in the first 64k, we cannot "just" use a + function pointer to point to a trampoline on the stack. So, we + create N fixed trampolines that read from an array, and allocate + them as needed. + +*/ + +#include "vregs.h" + + .data + .p2align 1 +trampoline_array: + + .macro stub n + + .text +trampoline_\n: + .type trampoline_\n, @function + movw ax, !trampoline_chain_\n + movw r14, ax + movw ax, !trampoline_addr_\n + br ax + .size trampoline_\n, .-trampoline_\n + + .data +trampoline_frame_\n: + .short 0 +trampoline_stub_\n: + .short trampoline_\n +trampoline_chain_\n: + .short 0 +trampoline_addr_\n: + .short 0 + +#define TO_FRAME 0 +#define TO_STUB 2 +#define TO_CHAIN 4 +#define TO_ADDR 6 +#define TO_SIZE 8 + + .endm + + stub 0 + stub 1 + stub 2 + stub 3 + stub 4 + stub 5 + +trampoline_array_end: + +/* Given the function pointer in R8 and the static chain + pointer in R10, allocate a trampoline and return its address in + R8. */ + + .text + .global ___trampoline_init + .type ___trampoline_init, @function +___trampoline_init: + + movw hl, #trampoline_array +1: + movw ax, [hl + TO_ADDR] + cmpw ax, #0 + bz $2f + + movw ax, hl + addw ax, #TO_SIZE + movw hl, ax + cmpw ax, #trampoline_array_end + bnz $1b + brk ; no more slots? + +2: movw ax, r8 + movw [hl + TO_ADDR], ax + movw ax, r10 + movw [hl + TO_CHAIN], ax + movw ax, sp + movw [hl + TO_FRAME], ax + + movw ax, [hl + TO_STUB] + movw r8, ax + + ret + .size ___trampoline_init, . - ___trampoline_init + + .global ___trampoline_uninit + .type ___trampoline_uninit, @function +___trampoline_uninit: + movw hl, #trampoline_array + movw ax, sp + movw bc, ax +1: + movw ax, [hl + TO_FRAME] + cmpw ax, bc + bc $2f + + clrw ax + movw [hl + TO_ADDR], ax + +2: + movw ax, hl + addw ax, #TO_SIZE + movw hl, ax + cmpw ax, #trampoline_array_end + bnz $1b + + ret + .size ___trampoline_uninit, . - ___trampoline_uninit |