On Linux, the profile runtime can use __start_SECTNAME and __stop_SECTNAME
symbols defined by the linker to locate the start and end location of
a named section (with C name). This eliminates the need for instrumented
binary to call __llvm_profile_register_function during start-up time.
llvm-svn: 250200
On Linux, the profile runtime can use __start_SECTNAME and __stop_SECTNAME
symbols defined by the linker to locate the start and end location of
a named section (with C name). This eliminates the need for instrumented
binary to call __llvm_profile_register_function during start-up time.
llvm-svn: 250199
PythonObjects were being incorrectly ref-counted. This problem was
pervasive throughout the codebase, leading to an unknown number of memory
leaks and potentially use-after-free.
The issue stems from the fact that Python native methods can either return
"borrowed" references or "owned" references. For the former category, you
*must* incref it prior to decrefing it. And for the latter category, you
should not incref it before decrefing it. This is mostly an issue when a
Python C API method returns a `PyObject` to you, but it can also happen with
a method accepts a `PyObject`. Notably, this happens in `PyList_SetItem`,
which is documented to "steal" the reference that you give it. So if you
pass something to `PyList_SetItem`, you cannot hold onto it unless you
incref it first. But since this is one of only two exceptions in the
entire API, it's confusing and difficult to remember.
Our `PythonObject` class was indiscriminantely increfing every object it
received, which means that if you passed it an owned reference, you now
have a dangling reference since owned references should not be increfed.
We were doing this in quite a few places.
There was also a fair amount of manual increfing and decrefing prevalent
throughout the codebase, which is easy to get wrong.
This patch solves the problem by making any construction of a
`PythonObject` from a `PyObject` take a flag which indicates whether it is
an owned reference or a borrowed reference. There is no way to construct a
`PythonObject` without this flag, and it does not offer a default value,
forcing the user to make an explicit decision every time.
All manual uses of `PyObject` have been cleaned up throughout the codebase
and replaced with `PythonObject` in order to make RAII the predominant
pattern when dealing with native Python objects.
Differential Revision: http://reviews.llvm.org/D13617
Reviewed By: Greg Clayton
llvm-svn: 250195
"finalize" does not give a hint about what that function is actually
going to do. This patch make it more specific by renaming scanShlibUndefined.
Also add a comment that we basically ignore undefined symbols in DSOs except
this function.
llvm-svn: 250191
The fix in r250109 to ensure a strict weak ordering in the section sorting was
a bit overzealous. We only use the NOBITS comparison if either A or B is a
NOBITS section. Otherwise, we fall through to the target-specific ranking
function. Failure to do this causes the sorting to fail in cases where, for
example, a .dynamic section happens to end up in between .got and .toc, etc. in
the initial ordering (.dynamic has a type SHT_DYNAMIC, compared to SHT_PROGBITS
or SHT_NOBITS).
llvm-svn: 250190
flag as it was a Mach-O universal file.
The default as to which architecture slice that is dumped without an -arch flag
depends on the host architecture and the contents of the universal file. The
malformed archive 00000031.a file has both an x86_64 and i386 slice. So for
for x86_64 hosts only that slice is dumped, for non-x86_64 hosts, which is many
of the bots both slices are dumped.
The test is intended to only check that the malformation of the x86_64 which
has a non-decimal characters in the size field of the archive header so it no
longer crashes.
The problem turned out that the i388 slice of the malformed archive had a
different malformation which was causing the non-x86_64 bots to get this error:
llvm-objdump -macho -disassemble -arch i386 00000031.a
Archive : .00000031.a
00000031.a(c_start.o):
LLVM ERROR: Symbol name entry points before beginning or past end of file.
and causing the test as it was written to fail. So by adding ‘-arch x86_64’ it
should correct the test and the malformation on the i388 slice will not be
dumped.
Also the removal of the malformed-machos mem-crup-0261.macho was not causing
the issue so that is put back in.
Sorry for the churn on these tests, Kev
llvm-svn: 250184
Summary:
Add an iterator that can walk across blocks and which visits the state
transitions rather than state ranges, with explicit transitions to -1
indicating the presence of top-level calls that may throw and cause the
current function to unwind to caller. This will simplify code that needs
to identify nested try regions.
Refactor SEH and C++EH table generation to use the new
InvokeStateChangeIterator, and remove the InvokeLabelIterator they were
using.
Reviewers: majnemer, andrew.w.kaylor, rnk
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D13623
llvm-svn: 250179
BSD's DSO files have undefined symbol "__progname" which is defined
in crt1.o. On that system, both user programs and system shared
libraries depend on each other.
In general, we need to put symbols defined by user programs which are
referenced by shared libraries to user program's .dynsym.
http://reviews.llvm.org/D13637
llvm-svn: 250176
Summary:
/usr/lib/debug doesn't exist on Windows so there's no point even
attempting to look for symbol files in there.
Reviewers: zturner, clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D13636
llvm-svn: 250175
What was done:
1) .got.plt section is created for functions that requires PLT. .got.plt has 3 predefined empty entries now that are required for dynamic linker.
Also other new items created are configured to have correct jump to PLT[N].
2) PLT section now has PLT[0] entry, also others ones are configured to support PLT->GOT(.got.plt) calls.
3) Implemented .rel[a].plt sections (based on patch http://reviews.llvm.org/D13569).
4) Fixed plt relocations types (based on patch http://reviews.llvm.org/D13589).
NOTES:
The .plt.got zero entry is still empty now. According to ELF specification it should hold the address of the dynamic structure, referenced with the symbol
_DYNAMIC. The _DYNAMIC entry points to the .dynamic section which contains information used by the ELF interpreter to setup the binary.
Differential Revision: http://reviews.llvm.org/D13651
llvm-svn: 250169
Now all Target<Arch> classes are used only in Target.cpp.
We can put them in an anonymous namespace. In order to avoid
merge conflict with other people's patches, I'll do that later.
llvm-svn: 250168
This is what most people want anyways. Clang -cc1's main() will override
this but for other tools this is the most sensible default and avoids
some work.
llvm-svn: 250164
As discussed in D13348 - the INSERTQI range combining code is wrong in that it confuses the insertion bit index with an extraction bit index.
The remaining legal combines are very unlikely (especially once we've converted to shuffles in D13348) so I'm removing the optimization.
llvm-svn: 250160
Now that all the known faults with GlobalsAA have been fixed, flip the big switch on -enable-non-lto-gmr again.
Feel free to pester me with any more bugs found, and don't hesitate to flip the switch back off.
llvm-svn: 250157
Weak linkage and friends allow a symbol to be overriden outside the
code generator's model, so GlobalsAA shouldn't assume that anything it
can compute about such a symbol is valid.
llvm-svn: 250156
Xinliang David Li