diff options
Diffstat (limited to 'src/pal/src/libunwind/src/x86/Gstep.c')
| -rw-r--r-- | src/pal/src/libunwind/src/x86/Gstep.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/pal/src/libunwind/src/x86/Gstep.c b/src/pal/src/libunwind/src/x86/Gstep.c new file mode 100644 index 0000000000..129b739a3e --- /dev/null +++ b/src/pal/src/libunwind/src/x86/Gstep.c @@ -0,0 +1,115 @@ +/* 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" + +int +unw_step (unw_cursor_t *cursor) +{ + struct cursor *c = (struct cursor *) cursor; + int ret, i; + + Debug (1, "(cursor=%p, ip=0x%08x)\n", c, (unsigned) c->dwarf.ip); + + /* Try DWARF-based unwinding... */ + ret = dwarf_step (&c->dwarf); + + if (ret < 0 && ret != -UNW_ENOINFO) + { + Debug (2, "returning %d\n", ret); + return ret; + } + + if (unlikely (ret < 0)) + { + /* DWARF failed, let's see if we can follow the frame-chain + or skip over the signal trampoline. */ + struct dwarf_loc ebp_loc, eip_loc; + + /* We could get here because of missing/bad unwind information. + Validate all addresses before dereferencing. */ + c->validate = 1; + + Debug (13, "dwarf_step() failed (ret=%d), trying frame-chain\n", ret); + + if (unw_is_signal_frame (cursor) > 0) + { + ret = x86_handle_signal_frame(cursor); + if (ret < 0) + { + Debug (2, "returning 0\n"); + return 0; + } + } + else + { + ret = dwarf_get (&c->dwarf, c->dwarf.loc[EBP], &c->dwarf.cfa); + if (ret < 0) + { + Debug (2, "returning %d\n", ret); + return ret; + } + + Debug (13, "[EBP=0x%x] = 0x%x\n", DWARF_GET_LOC (c->dwarf.loc[EBP]), + c->dwarf.cfa); + + ebp_loc = DWARF_LOC (c->dwarf.cfa, 0); + eip_loc = DWARF_LOC (c->dwarf.cfa + 4, 0); + c->dwarf.cfa += 8; + + /* Mark all registers unsaved, since we don't know where + they are saved (if at all), except for the EBP and + EIP. */ + for (i = 0; i < DWARF_NUM_PRESERVED_REGS; ++i) + c->dwarf.loc[i] = DWARF_NULL_LOC; + + c->dwarf.loc[EBP] = ebp_loc; + c->dwarf.loc[EIP] = eip_loc; + c->dwarf.use_prev_instr = 1; + } + + if (!DWARF_IS_NULL_LOC (c->dwarf.loc[EBP])) + { + ret = dwarf_get (&c->dwarf, c->dwarf.loc[EIP], &c->dwarf.ip); + if (ret < 0) + { + Debug (13, "dwarf_get([EIP=0x%x]) failed\n", DWARF_GET_LOC (c->dwarf.loc[EIP])); + Debug (2, "returning %d\n", ret); + return ret; + } + else + { + Debug (13, "[EIP=0x%x] = 0x%x\n", DWARF_GET_LOC (c->dwarf.loc[EIP]), + c->dwarf.ip); + } + } + else + c->dwarf.ip = 0; + } + ret = (c->dwarf.ip == 0) ? 0 : 1; + Debug (2, "returning %d\n", ret); + return ret; +} |