glibc/sysdeps/riscv/dl-trampoline.S

91 lines
2.6 KiB
ArmAsm

/* RISC-V PLT trampoline
Copyright (C) 2017-2020 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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <sys/asm.h>
/* Assembler veneer called from the PLT header code for lazy loading.
The PLT header passes its own args in t0-t2. */
#ifdef __riscv_float_abi_soft
# define FRAME_SIZE (-((-10 * SZREG) & ALMASK))
#else
# define FRAME_SIZE (-((-10 * SZREG - 8 * SZFREG) & ALMASK))
#endif
ENTRY (_dl_runtime_resolve)
# Save arguments to stack.
addi sp, sp, -FRAME_SIZE
REG_S ra, 9*SZREG(sp)
REG_S a0, 1*SZREG(sp)
REG_S a1, 2*SZREG(sp)
REG_S a2, 3*SZREG(sp)
REG_S a3, 4*SZREG(sp)
REG_S a4, 5*SZREG(sp)
REG_S a5, 6*SZREG(sp)
REG_S a6, 7*SZREG(sp)
REG_S a7, 8*SZREG(sp)
#ifndef __riscv_float_abi_soft
FREG_S fa0, (10*SZREG + 0*SZFREG)(sp)
FREG_S fa1, (10*SZREG + 1*SZFREG)(sp)
FREG_S fa2, (10*SZREG + 2*SZFREG)(sp)
FREG_S fa3, (10*SZREG + 3*SZFREG)(sp)
FREG_S fa4, (10*SZREG + 4*SZFREG)(sp)
FREG_S fa5, (10*SZREG + 5*SZFREG)(sp)
FREG_S fa6, (10*SZREG + 6*SZFREG)(sp)
FREG_S fa7, (10*SZREG + 7*SZFREG)(sp)
#endif
# Update .got.plt and obtain runtime address of callee.
slli a1, t1, 1
mv a0, t0 # link map
add a1, a1, t1 # reloc offset (== thrice the .got.plt offset)
la a2, _dl_fixup
jalr a2
mv t1, a0
# Restore arguments from stack.
REG_L ra, 9*SZREG(sp)
REG_L a0, 1*SZREG(sp)
REG_L a1, 2*SZREG(sp)
REG_L a2, 3*SZREG(sp)
REG_L a3, 4*SZREG(sp)
REG_L a4, 5*SZREG(sp)
REG_L a5, 6*SZREG(sp)
REG_L a6, 7*SZREG(sp)
REG_L a7, 8*SZREG(sp)
#ifndef __riscv_float_abi_soft
FREG_L fa0, (10*SZREG + 0*SZFREG)(sp)
FREG_L fa1, (10*SZREG + 1*SZFREG)(sp)
FREG_L fa2, (10*SZREG + 2*SZFREG)(sp)
FREG_L fa3, (10*SZREG + 3*SZFREG)(sp)
FREG_L fa4, (10*SZREG + 4*SZFREG)(sp)
FREG_L fa5, (10*SZREG + 5*SZFREG)(sp)
FREG_L fa6, (10*SZREG + 6*SZFREG)(sp)
FREG_L fa7, (10*SZREG + 7*SZFREG)(sp)
#endif
addi sp, sp, FRAME_SIZE
# Invoke the callee.
jr t1
END (_dl_runtime_resolve)