diff options
| author | Joerg Sonnenberger <joerg@bec.de> | 2014-03-20 01:23:55 +0000 |
|---|---|---|
| committer | Joerg Sonnenberger <joerg@bec.de> | 2014-03-20 01:23:55 +0000 |
| commit | 7dfc5215ff08e992ffe88c577ba15d641e610d75 (patch) | |
| tree | d06427900994288ecfb7f01742d852d3ae34e0a9 | |
| parent | 4fb4f2286edeef6320baa9b7ad475495f95c8c56 (diff) | |
| download | libcxxabi_35a-7dfc5215ff08e992ffe88c577ba15d641e610d75.tar.gz | |
Fix DW_CFA_GNU_args_size handling. The primary architecture using this
opcode is VAX. A function call pushes the number of arguments given onto
the stack and "ret" will pop it automatically. The FDE of the caller
contains the amount of stack space used for arguments (and possibly
extra padding), so unwinding has to compensate for this when "returning"
from a function. This is exactly the case when step() is done. The
existing handling in unw_set_reg no longer makes sense.
git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@204290 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | src/Unwind/UnwindCursor.hpp | 2 | ||||
| -rw-r--r-- | src/Unwind/libunwind.cpp | 3 |
2 files changed, 2 insertions, 3 deletions
diff --git a/src/Unwind/UnwindCursor.hpp b/src/Unwind/UnwindCursor.hpp index 256a72d..235922f 100644 --- a/src/Unwind/UnwindCursor.hpp +++ b/src/Unwind/UnwindCursor.hpp @@ -1041,6 +1041,8 @@ int UnwindCursor<A, R>::step() { this->setInfoBasedOnIPRegister(true); if (_unwindInfoMissing) return UNW_STEP_END; + if (_info.gp) + setReg(UNW_REG_SP, getReg(UNW_REG_SP) + _info.gp); } return result; diff --git a/src/Unwind/libunwind.cpp b/src/Unwind/libunwind.cpp index 2043ac2..59ff4a7 100644 --- a/src/Unwind/libunwind.cpp +++ b/src/Unwind/libunwind.cpp @@ -174,9 +174,6 @@ _LIBUNWIND_EXPORT int unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum, pint_t orgArgSize = (pint_t)info.gp; uint64_t orgFuncStart = info.start_ip; co->setInfoBasedOnIPRegister(false); - // and adjust REG_SP if there was a DW_CFA_GNU_args_size - if ((orgFuncStart == info.start_ip) && (orgArgSize != 0)) - co->setReg(UNW_REG_SP, co->getReg(UNW_REG_SP) + orgArgSize); } return UNW_ESUCCESS; } |