Dropping the extra frame for unw_backtrace itself using unw_step is
approximately 15% slower than skipping the frame in tdep_trace. So
drop the frame in the latter, and make the function a private
implementation detail for libunwind, not an exported interface.
Also moves unw_getcontext call back into unw_backtrace to avoid an
extra call frame in case slow_backtrace does not get inlined into
unw_backtrace.
Adds new function to perform a pure stack walk without unwinding,
functionally similar to backtrace() but accelerated by an address
attribute cache the caller maintains across calls.
Usually we don't have a valid location for the SP but we keep calculating
the value of the CFA. The ARM backend should return this value instead.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
Using malloc is not an option since unw_init_local and unw_step are supposed
to be async signal safe. Therefore this code path can be removed.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
There is no need for libunwind to set/fake a name of the elf file from which
the program header came from.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
DWARF expressions are more powerful than the ARM specific unwind tables.
Therefore DWARF should be the preferred unwind method.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
Move code that does not necessarily need to reside in the ex_tables.h header
file into ex_tables.c. Add comments and remove unused code.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
This eliminates the arm_stackframe and therefore the need to synchronize the
two models. It also clears the way for unwinding call stacks with mixed
DWARF- and extbl-frames.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
Uses ex_tables routines to provide a new means of unwinding the stack.
Set UNW_ARM_UNWIND_METHOD=4 to use ARM-specific unwinding tables.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
Implements a check for call to sigreturn that the kernel will have
setup before jumping to the signal handler.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
If mmap fails, be sure to close the maps file before returning an error.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Signed-off-by: Ken Werner <ken.werner@linaro.org>
This prevents the linker from complaining about a missing symbol when
building the test-setjmp test case.
Signed-off-by: Ken Werner <ken.werner@linaro.org>
in elf_map_image() to ensure mapped files have a valid ELF header.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Signed-off-by: Arun Sharma <asharma@fb.com>
Eliminates obfuscating variables in favor of adding files directly
to library SOURCES. Eliminates the need for EXTRA_DIST variable.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Rather than building the sources directly, create a library that
gets linked statically into libunwind.la and libunwind-$(arch).la.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Build DWARF source files into automake convenience libraries to
eliminate duplication in arch-dependent library build rules.
Adds a configure-time check to determine whether to use them.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Eliminate redundant listing of libunwind_setjmp source files by
using automake's '+=' operator.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Frees newly created address space memory in the event of a failure
caused by an endian mismatch.
Signed-off-by: Zachary T Welch <zwelch@codesourcery.com>
Current implementation fails to find separate debug symbols when
.gnu_debuglink is set to the same name of the target ELF basename
(e.g. "libc.so.6" for /lib/libc.so.6). This patch fixes this by ignoring
separate debug files that contain a .gnu_debuglink section.
It also fixes a small typo in a related Debug() line.
Signed-off-by: Andris Zeila <andris.zeila@accenture.com>
the instruction after the call for a normal frame. libunwind uses
IP-1 to lookup unwind information. However, this is not necessary for
interrupted frames such as signal frames (or interrupt frames) in
the kernel context.
This patch handles both cases correctly.
Based on work by Mark Wielaard <mwielaard@redhat.com>
