diff options
Diffstat (limited to 'src/third_party/unwind/dist/src/arm/Gos-linux.c')
| -rw-r--r-- | src/third_party/unwind/dist/src/arm/Gos-linux.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/third_party/unwind/dist/src/arm/Gos-linux.c b/src/third_party/unwind/dist/src/arm/Gos-linux.c new file mode 100644 index 00000000000..260e086f695 --- /dev/null +++ b/src/third_party/unwind/dist/src/arm/Gos-linux.c @@ -0,0 +1,182 @@ +/* libunwind - a platform-independent unwind library + Copyright (C) 2008 CodeSourcery + Copyright 2011 Linaro Limited + Copyright (C) 2012 Tommi Rantala <tt.rantala@gmail.com> + +This file is part of libunwind. + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ + +#include <stdio.h> +#include <signal.h> +#include "unwind_i.h" +#include "offsets.h" + +HIDDEN int +arm_handle_signal_frame (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + int ret; + unw_word_t sc_addr, sp, sp_addr = c->dwarf.cfa; + struct dwarf_loc sp_loc = DWARF_LOC (sp_addr, 0); + + if ((ret = dwarf_get (&c->dwarf, sp_loc, &sp)) < 0) + return -UNW_EUNSPEC; + + /* Obtain signal frame type (non-RT or RT). */ + ret = unw_is_signal_frame (cursor); + + /* Save the SP and PC to be able to return execution at this point + later in time (unw_resume). */ + c->sigcontext_sp = c->dwarf.cfa; + c->sigcontext_pc = c->dwarf.ip; + + /* Since kernel version 2.6.18 the non-RT signal frame starts with a + ucontext while the RT signal frame starts with a siginfo, followed + by a sigframe whose first element is an ucontext. + Prior 2.6.18 the non-RT signal frame starts with a sigcontext while + the RT signal frame starts with two pointers followed by a siginfo + and an ucontext. The first pointer points to the start of the siginfo + structure and the second one to the ucontext structure. */ + + if (ret == 1) + { + /* Handle non-RT signal frames. Check if the first word on the stack + is the magic number. */ + if (sp == 0x5ac3c35a) + { + c->sigcontext_format = ARM_SCF_LINUX_SIGFRAME; + sc_addr = sp_addr + LINUX_UC_MCONTEXT_OFF; + } + else + { + c->sigcontext_format = ARM_SCF_LINUX_OLD_SIGFRAME; + sc_addr = sp_addr; + } + } + else if (ret == 2) + { + /* Handle RT signal frames. Check if the first word on the stack is a + pointer to the siginfo structure. */ + if (sp == sp_addr + 8) + { + c->sigcontext_format = ARM_SCF_LINUX_OLD_RT_SIGFRAME; + sc_addr = sp_addr + 8 + sizeof (siginfo_t) + LINUX_UC_MCONTEXT_OFF; + } + else + { + c->sigcontext_format = ARM_SCF_LINUX_RT_SIGFRAME; + sc_addr = sp_addr + sizeof (siginfo_t) + LINUX_UC_MCONTEXT_OFF; + } + } + else + return -UNW_EUNSPEC; + + c->sigcontext_addr = sc_addr; + c->frame_info.frame_type = UNW_ARM_FRAME_SIGRETURN; + c->frame_info.cfa_reg_offset = sc_addr - sp_addr; + + /* Update the dwarf cursor. + Set the location of the registers to the corresponding addresses of the + uc_mcontext / sigcontext structure contents. */ + c->dwarf.loc[UNW_ARM_R0] = DWARF_LOC (sc_addr + LINUX_SC_R0_OFF, 0); + c->dwarf.loc[UNW_ARM_R1] = DWARF_LOC (sc_addr + LINUX_SC_R1_OFF, 0); + c->dwarf.loc[UNW_ARM_R2] = DWARF_LOC (sc_addr + LINUX_SC_R2_OFF, 0); + c->dwarf.loc[UNW_ARM_R3] = DWARF_LOC (sc_addr + LINUX_SC_R3_OFF, 0); + c->dwarf.loc[UNW_ARM_R4] = DWARF_LOC (sc_addr + LINUX_SC_R4_OFF, 0); + c->dwarf.loc[UNW_ARM_R5] = DWARF_LOC (sc_addr + LINUX_SC_R5_OFF, 0); + c->dwarf.loc[UNW_ARM_R6] = DWARF_LOC (sc_addr + LINUX_SC_R6_OFF, 0); + c->dwarf.loc[UNW_ARM_R7] = DWARF_LOC (sc_addr + LINUX_SC_R7_OFF, 0); + c->dwarf.loc[UNW_ARM_R8] = DWARF_LOC (sc_addr + LINUX_SC_R8_OFF, 0); + c->dwarf.loc[UNW_ARM_R9] = DWARF_LOC (sc_addr + LINUX_SC_R9_OFF, 0); + c->dwarf.loc[UNW_ARM_R10] = DWARF_LOC (sc_addr + LINUX_SC_R10_OFF, 0); + c->dwarf.loc[UNW_ARM_R11] = DWARF_LOC (sc_addr + LINUX_SC_FP_OFF, 0); + c->dwarf.loc[UNW_ARM_R12] = DWARF_LOC (sc_addr + LINUX_SC_IP_OFF, 0); + c->dwarf.loc[UNW_ARM_R13] = DWARF_LOC (sc_addr + LINUX_SC_SP_OFF, 0); + c->dwarf.loc[UNW_ARM_R14] = DWARF_LOC (sc_addr + LINUX_SC_LR_OFF, 0); + c->dwarf.loc[UNW_ARM_R15] = DWARF_LOC (sc_addr + LINUX_SC_PC_OFF, 0); + + /* Set SP/CFA and PC/IP. */ + dwarf_get (&c->dwarf, c->dwarf.loc[UNW_ARM_R13], &c->dwarf.cfa); + dwarf_get (&c->dwarf, c->dwarf.loc[UNW_ARM_R15], &c->dwarf.ip); + + c->dwarf.pi_valid = 0; + + return 1; +} + +#define ARM_NR_sigreturn 119 +#define ARM_NR_rt_sigreturn 173 +#define ARM_NR_OABI_SYSCALL_BASE 0x900000 + +/* ARM EABI sigreturn (the syscall number is loaded into r7) */ +#define MOV_R7_SIGRETURN (0xe3a07000UL | ARM_NR_sigreturn) +#define MOV_R7_RT_SIGRETURN (0xe3a07000UL | ARM_NR_rt_sigreturn) + +/* ARM OABI sigreturn (using SWI) */ +#define ARM_SIGRETURN \ + (0xef000000UL | ARM_NR_sigreturn | ARM_NR_OABI_SYSCALL_BASE) +#define ARM_RT_SIGRETURN \ + (0xef000000UL | ARM_NR_rt_sigreturn | ARM_NR_OABI_SYSCALL_BASE) + +/* Thumb sigreturn (two insns, syscall number is loaded into r7) */ +#define THUMB_SIGRETURN (0xdf00UL << 16 | 0x2700 | ARM_NR_sigreturn) +#define THUMB_RT_SIGRETURN (0xdf00UL << 16 | 0x2700 | ARM_NR_rt_sigreturn) + +/* Thumb2 sigreturn (mov.w r7, $SYS_ify(rt_sigreturn/sigreturn)) */ +#define THUMB2_SIGRETURN (((0x0700 | ARM_NR_sigreturn) << 16) | \ + 0xf04f) +#define THUMB2_RT_SIGRETURN (((0x0700 | ARM_NR_rt_sigreturn) << 16) | \ + 0xf04f) +/* TODO: with different toolchains, there are a lot more possibilities */ + +/* Returns 1 in case of a non-RT signal frame and 2 in case of a RT signal + frame. */ +int +unw_is_signal_frame (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + unw_word_t w0, ip; + unw_addr_space_t as; + unw_accessors_t *a; + void *arg; + int ret; + + as = c->dwarf.as; + a = unw_get_accessors_int (as); + arg = c->dwarf.as_arg; + + /* The least bit denotes thumb/arm mode. Do not read there. */ + ip = c->dwarf.ip & ~0x1; + + if ((ret = (*a->access_mem) (as, ip, &w0, 0, arg)) < 0) + return ret; + + /* Return 1 if the IP points to a non-RT sigreturn sequence. */ + if (w0 == MOV_R7_SIGRETURN || w0 == ARM_SIGRETURN || w0 == THUMB_SIGRETURN + || w0 == THUMB2_SIGRETURN) + return 1; + /* Return 2 if the IP points to a RT sigreturn sequence. */ + else if (w0 == MOV_R7_RT_SIGRETURN || w0 == ARM_RT_SIGRETURN + || w0 == THUMB_RT_SIGRETURN || w0 == THUMB2_RT_SIGRETURN) + return 2; + + return 0; +} |