diff options
Diffstat (limited to 'src/third_party/unwind/dist/src/x86/Gos-linux.c')
-rw-r--r-- | src/third_party/unwind/dist/src/x86/Gos-linux.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/src/third_party/unwind/dist/src/x86/Gos-linux.c b/src/third_party/unwind/dist/src/x86/Gos-linux.c new file mode 100644 index 00000000000..fb9a5e34612 --- /dev/null +++ b/src/third_party/unwind/dist/src/x86/Gos-linux.c @@ -0,0 +1,331 @@ +/* libunwind - a platform-independent unwind library + Copyright (C) 2002-2004 Hewlett-Packard Co + Contributed by David Mosberger-Tang <davidm@hpl.hp.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 "unwind_i.h" +#include "offsets.h" + +#include <sys/syscall.h> + +int +unw_is_signal_frame (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + unw_word_t w0, w1, 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; + + /* Check if EIP points at sigreturn() sequence. On Linux, this is: + + __restore: + 0x58 pop %eax + 0xb8 0x77 0x00 0x00 0x00 movl 0x77,%eax + 0xcd 0x80 int 0x80 + + without SA_SIGINFO, and + + __restore_rt: + 0xb8 0xad 0x00 0x00 0x00 movl 0xad,%eax + 0xcd 0x80 int 0x80 + 0x00 + + if SA_SIGINFO is specified. + */ + ip = c->dwarf.ip; + if ((*a->access_mem) (as, ip, &w0, 0, arg) < 0 + || (*a->access_mem) (as, ip + 4, &w1, 0, arg) < 0) + ret = 0; + else + ret = ((w0 == 0x0077b858 && w1 == 0x80cd0000) + || (w0 == 0x0000adb8 && (w1 & 0xffffff) == 0x80cd00)); + Debug (16, "returning %d\n", ret); + return ret; +} + +HIDDEN int +x86_handle_signal_frame (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + int ret; + + /* c->esp points at the arguments to the handler. Without + SA_SIGINFO, the arguments consist of a signal number + followed by a struct sigcontext. With SA_SIGINFO, the + arguments consist a signal number, a siginfo *, and a + ucontext *. */ + unw_word_t sc_addr; + unw_word_t siginfo_ptr_addr = c->dwarf.cfa + 4; + unw_word_t sigcontext_ptr_addr = c->dwarf.cfa + 8; + unw_word_t siginfo_ptr, sigcontext_ptr; + struct dwarf_loc esp_loc, siginfo_ptr_loc, sigcontext_ptr_loc; + + siginfo_ptr_loc = DWARF_LOC (siginfo_ptr_addr, 0); + sigcontext_ptr_loc = DWARF_LOC (sigcontext_ptr_addr, 0); + ret = (dwarf_get (&c->dwarf, siginfo_ptr_loc, &siginfo_ptr) + | dwarf_get (&c->dwarf, sigcontext_ptr_loc, &sigcontext_ptr)); + if (ret < 0) + { + Debug (2, "returning 0\n"); + return 0; + } + if (siginfo_ptr < c->dwarf.cfa + || siginfo_ptr > c->dwarf.cfa + 256 + || sigcontext_ptr < c->dwarf.cfa + || sigcontext_ptr > c->dwarf.cfa + 256) + { + /* Not plausible for SA_SIGINFO signal */ + c->sigcontext_format = X86_SCF_LINUX_SIGFRAME; + c->sigcontext_addr = sc_addr = c->dwarf.cfa + 4; + } + else + { + /* If SA_SIGINFO were not specified, we actually read + various segment pointers instead. We believe that at + least fs and _fsh are always zero for linux, so it is + not just unlikely, but impossible that we would end + up here. */ + c->sigcontext_format = X86_SCF_LINUX_RT_SIGFRAME; + c->sigcontext_addr = sigcontext_ptr; + sc_addr = sigcontext_ptr + LINUX_UC_MCONTEXT_OFF; + } + esp_loc = DWARF_LOC (sc_addr + LINUX_SC_ESP_OFF, 0); + ret = dwarf_get (&c->dwarf, esp_loc, &c->dwarf.cfa); + if (ret < 0) + { + Debug (2, "returning 0\n"); + return 0; + } + + c->dwarf.loc[EAX] = DWARF_LOC (sc_addr + LINUX_SC_EAX_OFF, 0); + c->dwarf.loc[ECX] = DWARF_LOC (sc_addr + LINUX_SC_ECX_OFF, 0); + c->dwarf.loc[EDX] = DWARF_LOC (sc_addr + LINUX_SC_EDX_OFF, 0); + c->dwarf.loc[EBX] = DWARF_LOC (sc_addr + LINUX_SC_EBX_OFF, 0); + c->dwarf.loc[EBP] = DWARF_LOC (sc_addr + LINUX_SC_EBP_OFF, 0); + c->dwarf.loc[ESI] = DWARF_LOC (sc_addr + LINUX_SC_ESI_OFF, 0); + c->dwarf.loc[EDI] = DWARF_LOC (sc_addr + LINUX_SC_EDI_OFF, 0); + c->dwarf.loc[EFLAGS] = DWARF_NULL_LOC; + c->dwarf.loc[TRAPNO] = DWARF_NULL_LOC; + c->dwarf.loc[ST0] = DWARF_NULL_LOC; + c->dwarf.loc[EIP] = DWARF_LOC (sc_addr + LINUX_SC_EIP_OFF, 0); + c->dwarf.loc[ESP] = DWARF_LOC (sc_addr + LINUX_SC_ESP_OFF, 0); + + return 0; +} + +HIDDEN dwarf_loc_t +x86_get_scratch_loc (struct cursor *c, unw_regnum_t reg) +{ + unw_word_t addr = c->sigcontext_addr, fpstate_addr, off; + int ret, is_fpstate = 0; + + switch (c->sigcontext_format) + { + case X86_SCF_NONE: + return DWARF_REG_LOC (&c->dwarf, reg); + + case X86_SCF_LINUX_SIGFRAME: + break; + + case X86_SCF_LINUX_RT_SIGFRAME: + addr += LINUX_UC_MCONTEXT_OFF; + break; + + default: + return DWARF_NULL_LOC; + } + + switch (reg) + { + case UNW_X86_GS: off = LINUX_SC_GS_OFF; break; + case UNW_X86_FS: off = LINUX_SC_FS_OFF; break; + case UNW_X86_ES: off = LINUX_SC_ES_OFF; break; + case UNW_X86_DS: off = LINUX_SC_DS_OFF; break; + case UNW_X86_EDI: off = LINUX_SC_EDI_OFF; break; + case UNW_X86_ESI: off = LINUX_SC_ESI_OFF; break; + case UNW_X86_EBP: off = LINUX_SC_EBP_OFF; break; + case UNW_X86_ESP: off = LINUX_SC_ESP_OFF; break; + case UNW_X86_EBX: off = LINUX_SC_EBX_OFF; break; + case UNW_X86_EDX: off = LINUX_SC_EDX_OFF; break; + case UNW_X86_ECX: off = LINUX_SC_ECX_OFF; break; + case UNW_X86_EAX: off = LINUX_SC_EAX_OFF; break; + case UNW_X86_TRAPNO: off = LINUX_SC_TRAPNO_OFF; break; + case UNW_X86_EIP: off = LINUX_SC_EIP_OFF; break; + case UNW_X86_CS: off = LINUX_SC_CS_OFF; break; + case UNW_X86_EFLAGS: off = LINUX_SC_EFLAGS_OFF; break; + case UNW_X86_SS: off = LINUX_SC_SS_OFF; break; + + /* The following is probably not correct for all possible cases. + Somebody who understands this better should review this for + correctness. */ + + case UNW_X86_FCW: is_fpstate = 1; off = LINUX_FPSTATE_CW_OFF; break; + case UNW_X86_FSW: is_fpstate = 1; off = LINUX_FPSTATE_SW_OFF; break; + case UNW_X86_FTW: is_fpstate = 1; off = LINUX_FPSTATE_TAG_OFF; break; + case UNW_X86_FCS: is_fpstate = 1; off = LINUX_FPSTATE_CSSEL_OFF; break; + case UNW_X86_FIP: is_fpstate = 1; off = LINUX_FPSTATE_IPOFF_OFF; break; + case UNW_X86_FEA: is_fpstate = 1; off = LINUX_FPSTATE_DATAOFF_OFF; break; + case UNW_X86_FDS: is_fpstate = 1; off = LINUX_FPSTATE_DATASEL_OFF; break; + case UNW_X86_MXCSR: is_fpstate = 1; off = LINUX_FPSTATE_MXCSR_OFF; break; + + /* stacked fp registers */ + case UNW_X86_ST0: case UNW_X86_ST1: case UNW_X86_ST2: case UNW_X86_ST3: + case UNW_X86_ST4: case UNW_X86_ST5: case UNW_X86_ST6: case UNW_X86_ST7: + is_fpstate = 1; + off = LINUX_FPSTATE_ST0_OFF + 10*(reg - UNW_X86_ST0); + break; + + /* SSE fp registers */ + case UNW_X86_XMM0_lo: case UNW_X86_XMM0_hi: + case UNW_X86_XMM1_lo: case UNW_X86_XMM1_hi: + case UNW_X86_XMM2_lo: case UNW_X86_XMM2_hi: + case UNW_X86_XMM3_lo: case UNW_X86_XMM3_hi: + case UNW_X86_XMM4_lo: case UNW_X86_XMM4_hi: + case UNW_X86_XMM5_lo: case UNW_X86_XMM5_hi: + case UNW_X86_XMM6_lo: case UNW_X86_XMM6_hi: + case UNW_X86_XMM7_lo: case UNW_X86_XMM7_hi: + is_fpstate = 1; + off = LINUX_FPSTATE_XMM0_OFF + 8*(reg - UNW_X86_XMM0_lo); + break; + case UNW_X86_XMM0: + case UNW_X86_XMM1: + case UNW_X86_XMM2: + case UNW_X86_XMM3: + case UNW_X86_XMM4: + case UNW_X86_XMM5: + case UNW_X86_XMM6: + case UNW_X86_XMM7: + is_fpstate = 1; + off = LINUX_FPSTATE_XMM0_OFF + 16*(reg - UNW_X86_XMM0); + break; + + case UNW_X86_FOP: + case UNW_X86_TSS: + case UNW_X86_LDT: + default: + return DWARF_REG_LOC (&c->dwarf, reg); + } + + if (is_fpstate) + { + if ((ret = dwarf_get (&c->dwarf, + DWARF_MEM_LOC (&c->dwarf, + addr + LINUX_SC_FPSTATE_OFF), + &fpstate_addr)) < 0) + return DWARF_NULL_LOC; + + if (!fpstate_addr) + return DWARF_NULL_LOC; + + return DWARF_MEM_LOC (c, fpstate_addr + off); + } + else + return DWARF_MEM_LOC (c, addr + off); +} + +#ifndef UNW_REMOTE_ONLY +HIDDEN void * +x86_r_uc_addr (ucontext_t *uc, int reg) +{ + void *addr; + + switch (reg) + { + case UNW_X86_GS: addr = &uc->uc_mcontext.gregs[REG_GS]; break; + case UNW_X86_FS: addr = &uc->uc_mcontext.gregs[REG_FS]; break; + case UNW_X86_ES: addr = &uc->uc_mcontext.gregs[REG_ES]; break; + case UNW_X86_DS: addr = &uc->uc_mcontext.gregs[REG_DS]; break; + case UNW_X86_EAX: addr = &uc->uc_mcontext.gregs[REG_EAX]; break; + case UNW_X86_EBX: addr = &uc->uc_mcontext.gregs[REG_EBX]; break; + case UNW_X86_ECX: addr = &uc->uc_mcontext.gregs[REG_ECX]; break; + case UNW_X86_EDX: addr = &uc->uc_mcontext.gregs[REG_EDX]; break; + case UNW_X86_ESI: addr = &uc->uc_mcontext.gregs[REG_ESI]; break; + case UNW_X86_EDI: addr = &uc->uc_mcontext.gregs[REG_EDI]; break; + case UNW_X86_EBP: addr = &uc->uc_mcontext.gregs[REG_EBP]; break; + case UNW_X86_EIP: addr = &uc->uc_mcontext.gregs[REG_EIP]; break; + case UNW_X86_ESP: addr = &uc->uc_mcontext.gregs[REG_ESP]; break; + case UNW_X86_TRAPNO: addr = &uc->uc_mcontext.gregs[REG_TRAPNO]; break; + case UNW_X86_CS: addr = &uc->uc_mcontext.gregs[REG_CS]; break; + case UNW_X86_EFLAGS: addr = &uc->uc_mcontext.gregs[REG_EFL]; break; + case UNW_X86_SS: addr = &uc->uc_mcontext.gregs[REG_SS]; break; + + default: + addr = NULL; + } + return addr; +} + +HIDDEN int +x86_local_resume (unw_addr_space_t as, unw_cursor_t *cursor, void *arg) +{ + struct cursor *c = (struct cursor *) cursor; + ucontext_t *uc = c->uc; + + /* Ensure c->pi is up-to-date. On x86, it's relatively common to be + missing DWARF unwind info. We don't want to fail in that case, + because the frame-chain still would let us do a backtrace at + least. */ + dwarf_make_proc_info (&c->dwarf); + + if (unlikely (c->sigcontext_format != X86_SCF_NONE)) + { + struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr; + + Debug (8, "resuming at ip=%x via sigreturn(%p)\n", c->dwarf.ip, sc); + x86_sigreturn (sc); + } + else + { + Debug (8, "resuming at ip=%x via setcontext()\n", c->dwarf.ip); + setcontext (uc); + } + return -UNW_EINVAL; +} + +/* sigreturn() is a no-op on x86 glibc. */ +HIDDEN void +x86_sigreturn (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr; + mcontext_t *sc_mcontext = &((ucontext_t*)sc)->uc_mcontext; + /* Copy in saved uc - all preserved regs are at the start of sigcontext */ + memcpy(sc_mcontext, &c->uc->uc_mcontext, + DWARF_NUM_PRESERVED_REGS * sizeof(unw_word_t)); + + Debug (8, "resuming at ip=%llx via sigreturn(%p)\n", + (unsigned long long) c->dwarf.ip, sc); + __asm__ __volatile__ ("mov %0, %%esp;" + "mov %1, %%eax;" + "syscall" + :: "r"(sc), "i"(SYS_rt_sigreturn) + : "memory"); + abort(); +} +#endif |