This new IR facility allows us to represent the object-file semantic of
a COMDAT group.
COMDATs allow us to tie together sections and make the inclusion of one
dependent on another. This is required to implement features like MS
ABI VFTables and optimizing away certain kinds of initialization in C++.
This functionality is only representable in COFF and ELF, Mach-O has no
similar mechanism.
Differential Revision: http://reviews.llvm.org/D4178
llvm-svn: 211920
By default, CMake will set NDEBUG in Rel* builds and leave it off in
debug builds, so we shouldn't need to do anything ourselves.
Before this change, it was possible to a Debug build without assertions
(aka Debug-Asserts in the autoconf system) by configuring with
-DLLVM_ENABLE_ASSERTIONS=OFF, but this configuration isn't very useful.
You can still get the same effect by explicitly adding -DNDEBUG to
CFLAGS.
Differential Revision: http://reviews.llvm.org/D4257
Patch by Janusz Sobczak!
llvm-svn: 211919
where there is no timeout. In the case where there is a timeout though, the
code is still wrong since it doesn't check that the alarm really went off.
Without this patch, I cannot debug a program that forks itself using
sys::ExecuteAndWait with lldb.
llvm-svn: 211918
This removes a const_cast added in r211884 that occurred due to an
inconsistency in how MemoryBuffers are handled between some parts of
clang and LLVM.
MemoryBuffers are immutable and the general convention in the LLVM
project is to omit const from immutable types as it's simply
redundant/verbose (see llvm::Type, for example). While this change
doesn't remove "const" from /every/ MemoryBuffer, it at least makes this
chain of ownership/usage consistent.
llvm-svn: 211915
COFF sections in MC were represented by a tuple of section-name and
COMDAT-name. This is not sufficient to represent a .text section
associated with another .text section; we need a way to distinguish
between the key section and the one marked associative.
llvm-svn: 211913
This isn't 100% compatible with MSVC, but it's close enough. MSVC's /EH
flag doesn't really control exceptions so much as how to clean up after
an exception is thrown. The upshot is that cl.exe /EHs- will compile
try, throw, and catch statements with a warning, but clang-cl will
reject such constructs with a hard error. We can't compile such EH
constructs anyway, but this may matter to consumers of the AST.
Reviewers: hans
Differential Revision: http://reviews.llvm.org/D4317
llvm-svn: 211909
Previously ObjectFileELF was simplifying and assuming the object file it was
looking at was the same as the host architecture/triple. This would break
attempts to run, say, lldb on MacOSX against lldb-gdbserver on Linux since
the MacOSX lldb would say that the linux elf file was really an Apple MacOSX
architecture. Chaos would ensue.
This change allows the elf file to parse ELF notes for Linux, FreeBSD and
NetBSD, and determine the OS appropriately from them. It also initializes
the OS type from the ELF header OSABI if it is set (which it is for FreeBSD
but not for Linux).
Added a test with freebsd and linux images that verify that
'(lldb) image list -t -A' prints out the expected architecture for each.
llvm-svn: 211907
error handler is only registered once.
To avoid the use of std::call_once (the obvious way to do this) I've
wrapped everything up into a managed static and done the work in
a constructor. Silly, but it should be effective.
Some out-of-tree libclang users reported this to me, and I've asked them
to put together a test case which exhibits this behavior, but I wanted
to fix things ASAP since the nature of the fix is straight forward.
llvm-svn: 211905
FreeBSD core files, for example, have no sections (only program headers).
llvm.org/pr20139
Differential Revision: http://reviews.llvm.org/D4323
llvm-svn: 211904
selection re-enabled in r211900 in LLVM.
The approach (unlike r211121) doesn't rely on std::mutex or
std::call_once to avoid breaknig cygwin bots.
llvm-svn: 211901
python bindings.
For example, this prevents errors on systems that disable python because
the system python isn't available. Without this, we still try to install
things and get install errors when that doesn't work.
llvm-svn: 211899
This is a fix to the code in clang which inserts padding arguments to
ensure that the ARM backend can emit AAPCS-VFP compliant code. This code
needs to track the number of registers which have been allocated in order
to do this. When passing a very large struct (>64 bytes) by value, clang
emits IR which takes a pointer to the struct, but the backend converts this
back to passing the struct in registers and on the stack. The bug was that
this was being considered by clang to only use one register, meaning that
there were situations in which padding arguments were incorrectly emitted
by clang.
llvm-svn: 211898
I've run into a bug where current LLVM at -O0 (with fast-isel)
generated invalid code like:
ld 0, 20936(1) # 8-byte Folded Reload
stw 12, 10348(0)
stw 12, 10344(0)
The underlying vreg had been introduced as base register by the
Local Stack Slot Allocation pass. That register was constrained
to G8RC by PPCRegisterInfo::materializeFrameBaseRegister to match
the ADDI instruction used to set it, but it was *not* constrained
to G8RC_NOX0 to fit the *use* of the register in an address.
That should have happened in PPCRegisterInfo::resolveFrameIndex.
This patch adds an appropriate constrainRegClass call.
Reviewed by Hal Finkel.
llvm-svn: 211897
The NEON intrinsics in arm_neon.h are designed to work on vectors
"as-if" loaded by (V)LDR. We load vectors "as-if" (V)LD1, so the
intrinsics are currently incorrect.
This patch adds big-endian versions of the intrinsics that does the
"obvious but dumb" thing of reversing all vector inputs and all
vector outputs. This will produce extra REVs, but we trust the
optimizer to remove them.
llvm-svn: 211893
Summary:
This allows it to fold pshufd instructions across intervening
half-shuffles and other noise. This pattern actually shows up in the
generic lowering tests, but I've also added direct tests using
intrinsics to make sure that the specific desired functionality is
working even if the lowering stuff changes in the future.
Differential Revision: http://reviews.llvm.org/D4292
llvm-svn: 211892
half-shuffles, even looking through intervening instructions in a chain.
Summary:
This doesn't happen to show up with any test cases I've found for the current
shuffle lowering, but previous attempts would benefit from this and it seems
generally useful. I've tested it directly using intrinsics, which also shows
that it will work with hand vectorized code as well.
Note that even though pshufd isn't directly used in these tests, it gets
exercised because we combine some of the half shuffles into a pshufd
first, and then merge them.
Differential Revision: http://reviews.llvm.org/D4291
llvm-svn: 211890
trivially redundant.
This fixes several cases in the new vector shuffle lowering algorithm
which would generate redundant shuffle instructions for the sake of
simplicity.
I'm also deleting a testcase which was somewhat ridiculous. It was
checking for a bug in 2007 about incorrectly transforming shuffles by
looking for the string "-86" in the output of a pretty substantial
function. This test case doesn't seem to have any value at this point.
Differential Revision: http://reviews.llvm.org/D4240
llvm-svn: 211889
x86 backend.
This sketches out a new code path for vector lowering, hidden behind an
off-by-default flag while it is under development. The fundamental idea
behind the new code path is to aggressively break down the problem space
in ways that ease selecting the odd set of instructions available on
x86, and carefully avoid scalarizing code even when forced to use older
ISAs. Notably, this starts off restricting itself to SSE2 and implements
the complete vector shuffle and blend space for 128-bit vectors in SSE2
without scalarizing. The plan is to layer on top of this ISA extensions
where we can bail out of the complex SSE2 lowering and opt for
a cheaper, specialized instruction (or set of instructions). It also
needs to be generalized to AVX and AVX512 vector widths.
Currently, this does a decent but not perfect job for SSE2. There are
some specific shortcomings that I plan to address:
- We need a peephole combine to fold together shuffles where possible.
There are cases where a previous shuffle could be modified slightly to
arrange for elements to be in the correct position and a later shuffle
eliminated. Doing this eagerly added quite a bit of complexity, and
so my plan is to combine away these redundancies afterward.
- There are a lot more clever ways to use unpck and pack that need to be
added. This is essential for real world shuffles as it turns out...
Once SSE2 is polished a bit I should be able to get interesting numbers
on performance improvements on benchmarks conducive to vectorization.
All of this will be off by default until it is functionally equivalent
of course.
Differential Revision: http://reviews.llvm.org/D4225
llvm-svn: 211888
Summary: This unbreaks our internal build after these tests were turned on in r211738.
Reviewers: chandlerc
Reviewed By: chandlerc
Subscribers: benlangmuir, cfe-commits
Differential Revision: http://reviews.llvm.org/D4311
llvm-svn: 211887
Current PPC64 RuntimeDyld code to handle TOC relocations has two
problems:
- With recent linkers, in addition to the relocations that implicitly
refer to the TOC base (R_PPC64_TOC*), you can now also use the .TOC.
magic symbol with any other relocation to refer to the TOC base
explicitly. This isn't currently used much in ELFv1 code (although
it could be), but it is essential in ELFv2 code.
- In a complex JIT environment with multiple modules, each module may
have its own .toc section, and TOC relocations in one module must
refer to *its own* TOC section. The current findPPC64TOC implementation
does not correctly implement this; in fact, it will always return the
address of the first TOC section it finds anywhere. (Note that at the
time findPPC64TOC is called, we don't even *know* which module the
relocation originally resided in, so it is not even possible to fix
this routine as-is.)
This commit fixes both problems by handling TOC relocations earlier, in
processRelocationRef. To do this, I've removed the findPPC64TOC routine
and replaced it by a new routine findPPC64TOCSection, which works
analogously to findOPDEntrySection in scanning the sections of the
ObjImage provided by its caller, processRelocationRef. This solves the
issue of finding the correct TOC section associated with the current
module.
This makes it straightforward to implement both R_PPC64_TOC relocations,
and relocations explicitly refering to the .TOC. symbol, directly in
processRelocationRef. There is now a new problem in implementing the
R_PPC64_TOC16* relocations, because those can now in theory involve
*three* different sections: the relocation may be applied in section A,
refer explicitly to a symbol in section B, and refer implicitly to the
TOC section C. The final processing of the relocation thus may only
happen after all three of these sections have been assigned final
addresses. There is currently no obvious means to implement this in
its general form with the common-code RuntimeDyld infrastructure.
Fortunately, ppc64 code usually makes no use of this most general form;
in fact, TOC16 relocations are only ever generated by LLVM for symbols
residing themselves in the TOC, which means "section B" == "section C"
in the above terminology. This special case can easily be handled with
the current infrastructure, and that is what this patch does.
[ Unhandled cases result in an explicit error, unlike the current code
which silently returns the wrong TOC base address ... ]
This patch makes the JIT work on both BE and LE (ELFv2 requires
additional patches, of course), and allowed me to successfully run
complex JIT scenarios (via mesa/llvmpipe).
Reviewed by Hal Finkel.
llvm-svn: 211885
This patch enables transforms for
(x + (~(y | c) + 1) --> x - (y | c) if c is odd
Differential Revision: http://reviews.llvm.org/D4210
llvm-svn: 211881
SystemZRegisterInfo and replace it with the subtarget as that's
all they needed in the first place. Update all uses and calls
accordingly.
llvm-svn: 211877
When we create a crashdump involving modules, we build a VFS to
reproduce the problem with. This updates the reproduction script to
use that VFS.
llvm-svn: 211876
Enabling -keep-going in ScopDetection causes expansion to an invalid
Scop candidate.
Region A <- Valid candidate
|
Region B <- Invalid candidate
If -keep-going is enabled, ScopDetection would expand A to A+B because
the RejectLog is never checked for errors during expansion.
With this patch only A becomes a valid Scop.
llvm-svn: 211875
This function is copying the entire file contents into memory repeatedly and
allocating new file IDs *each time* a source location is processed.
llvm-svn: 211874
Reverting this again, didn't mean to commit it - while r211872 fixes one
of the issues here, there are still others to figure out and address.
This reverts commit r211871.
llvm-svn: 211873