diff options
| -rw-r--r-- | backends/ChangeLog | 6 | ||||
| -rw-r--r-- | backends/Makefile.am | 3 | ||||
| -rw-r--r-- | backends/loongarch_init.c | 1 | ||||
| -rw-r--r-- | backends/loongarch_unwind.c | 84 |
4 files changed, 93 insertions, 1 deletions
diff --git a/backends/ChangeLog b/backends/ChangeLog index df762073..f1613d80 100644 --- a/backends/ChangeLog +++ b/backends/ChangeLog @@ -1,5 +1,11 @@ 2023-04-07 Youling Tang <tangyouling@loongson.cn> + * Makefile.am (loongarch_SRCS): Add loongarch_unwind.c. + * loongarch_init.c (loongarch_init): Hook unwind. + * loongarch_unwind.c: New file. + +2023-04-07 Youling Tang <tangyouling@loongson.cn> + * Makefile.am (loongarch_SRCS): Add loongarch_retval.c. * loongarch_init.c (loongarch_init): Hook return_value_location. * loongarch_retval.c: New file. diff --git a/backends/Makefile.am b/backends/Makefile.am index 50e78ea5..1261f5c6 100644 --- a/backends/Makefile.am +++ b/backends/Makefile.am @@ -97,7 +97,8 @@ csky_SRCS = csky_attrs.c csky_init.c csky_symbol.c csky_cfi.c \ csky_regs.c csky_initreg.c csky_corenote.c loongarch_SRCS = loongarch_init.c loongarch_symbol.c loongarch_cfi.c \ - loongarch_regs.c loongarch_retval.c + loongarch_regs.c loongarch_retval.c \ + loongarch_unwind.c arc_SRCS = arc_init.c arc_symbol.c diff --git a/backends/loongarch_init.c b/backends/loongarch_init.c index fd63f373..1e8846a8 100644 --- a/backends/loongarch_init.c +++ b/backends/loongarch_init.c @@ -54,6 +54,7 @@ loongarch_init (Elf *elf __attribute__ ((unused)), eh->frame_nregs = 74; HOOK (eh, check_special_symbol); HOOK (eh, return_value_location); + HOOK (eh, unwind); return eh; } diff --git a/backends/loongarch_unwind.c b/backends/loongarch_unwind.c new file mode 100644 index 00000000..fb748083 --- /dev/null +++ b/backends/loongarch_unwind.c @@ -0,0 +1,84 @@ +/* Get previous frame state for an existing frame state. + Copyright (C) 2023 OpenAnolis community LoongArch SIG. + Copyright (C) 2023 Loongson Technology Corporation Limited. + This file is part of elfutils. + + This file is free software; you can redistribute it and/or modify + it under the terms of either + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils 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. + + You should have received copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see <http://www.gnu.org/licenses/>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#define BACKEND loongarch_ +#define RA_REG 1 +#define SP_REG 3 +#define FP_REG 22 + +#define RA_OFFSET 8 +#define FP_OFFSET 16 + +#include "libebl_CPU.h" + +/* There was no CFI. Maybe we happen to have a frame pointer and can unwind from that? */ + +bool +EBLHOOK(unwind) (Ebl *ebl __attribute__ ((unused)), Dwarf_Addr pc __attribute__ ((unused)), + ebl_tid_registers_t *setfunc, ebl_tid_registers_get_t *getfunc, + ebl_pid_memory_read_t *readfunc, void *arg, + bool *signal_framep __attribute__ ((unused))) +{ + Dwarf_Word fp, ra, sp; + + if (!getfunc(RA_REG, 1, &ra, arg)) + return false; + + if (ra == 0 || !setfunc(-1, 1, &ra, arg)) + return false; + + if (!getfunc(FP_REG, 1, &fp, arg)) + fp = 0; + + if (!getfunc(SP_REG, 1, &sp, arg)) + sp = 0; + + Dwarf_Word newRa, newFp, newSp; + + if (!readfunc(fp - RA_OFFSET, &newRa, arg)) + newRa = 0; + + if (!readfunc(fp - FP_OFFSET, &newFp, arg)) + newFp = 0; + + newSp = fp; + + // These are not fatal if they don't work. They will just prevent unwinding at the next frame. + setfunc(RA_REG, 1, &newRa, arg); + setfunc(FP_REG, 1, &newFp, arg); + setfunc(SP_REG, 1, &newSp, arg); + + // If the fp is invalid, we might still have a valid ra. + // But if the fp is valid, then the stack should be moving in the right direction. + return fp == 0 || newSp > sp; +} |