In r212073 I missed a call of `use_begin()` that assumed the wrong
semantics. It's not clear to me at all what this code does without the
fix, so I'm not sure how to write a testcase.
AArch64AddressTypePromotion was doing nothing because it was using the
old semantics of `Use` and `uses()`, when it really wanted to get at the
`users()`.
David Blaikie [Mon, 30 Jun 2014 20:30:39 +0000 (20:30 +0000)]
DebugInfo: Preserve debug location information when transforming a call into an invoke during inlining.
This both improves basic debug info quality, but also fixes a larger
hole whenever we inline a call/invoke without a location (debug info for
the entire inlining is lost and other badness that the debug info
emission code is currently working around but shouldn't have to).
Kevin Enderby [Mon, 30 Jun 2014 18:45:23 +0000 (18:45 +0000)]
Add the -arch flag support to llvm-nm to select the slice out of a Mach-O
universal file. This also includes support for -arch all, selecting the host
architecture by default from a universal file and checking if -arch is used
with a standard Mach-O it matches that architecture.
Adrian Prantl [Mon, 30 Jun 2014 17:17:35 +0000 (17:17 +0000)]
Debug info: split out complex DIVariable address expressions into a
separate MDNode so they can be uniqued via folding set magic. To conserve
space, DIVariable nodes are still variable-length, with the last two
fields being optional.
No functional change.
http://reviews.llvm.org/D3526
Andrea Di Biagio [Mon, 30 Jun 2014 17:14:21 +0000 (17:14 +0000)]
[X86] Add support for builtin to read performance monitoring counters.
This patch adds support for a new builtin instruction called
__builtin_ia32_rdpmc.
Builtin '__builtin_ia32_rdpmc' is defined as a 'GCC builtin'; on X86, it can
be used to read performance monitoring counters. It takes as input the index
of the performance counter to read, and returns the value of the specified
performance counter as a 64-bit number.
Calls to this new builtin will map to instruction RDPMC.
The index in input to the builtin call is moved to register %ECX. The result
of the builtin call is the value of the specified performance counter (RDPMC
would return that quantity in registers RDX:RAX).
This patch:
- Adds builtin int_x86_rdpmc as a GCCBuiltin;
- Adds a new x86 DAG node called 'RDPMC_DAG';
- Teaches how to lower this new builtin;
- Adds an ISel pattern to select instruction RDPMC;
- Fixes the definition of instruction RDPMC adding %RAX and %RDX as
implicit definitions, and adding %ECX as implicit use;
- Adds a LLVM test to verify that the new builtin is correctly selected.
This exception format is not specific to Windows x64. A similar approach is
taken on nearly all architectures. Generalise the name to reflect reality.
This will eventually be used for Windows on ARM data emission as well.
Rename the routines to reflect the reality that they are more related to call
frame information than to Win64 EH. Although EH is implemented in an intertwined
manner by augmenting with an exception handler and an associated parameter, the
majority of these routines emit information required to unwind the frames. This
also helps identify that these routines are generic for most windows platforms
(they apply equally to nearly all architectures except x86) although the
encoding of the information is architecture dependent.
Unwinding data is emitted via EmitWinCFI* and exception handling information via
EmitWinEH*.
Chandler Carruth [Sat, 28 Jun 2014 05:46:28 +0000 (05:46 +0000)]
[x86] Fix a bug in the v8i16 shuffling exposed by the new splat-like
lowering for v16i8.
ASan and some bots caught this bug with existing test cases. Fixing it
even fixed a miscompile with one of the test cases. I'm still a bit
suspicious of this test case as I've not taken a proper amount of time
to think about it, but the fix here is strict goodness.
Chandler Carruth [Sat, 28 Jun 2014 05:18:49 +0000 (05:18 +0000)]
Fix this test to not write to the source tree, and instead to write to
a temporary file. This fixes the test in cases where the source tree is
mounted read-only.
Chandler Carruth [Sat, 28 Jun 2014 05:16:40 +0000 (05:16 +0000)]
[x86] Add handling for splat-like widenings of v16i8 shuffles.
These show up really frequently, not the least with actual splats. =] We
lowered these quite badly before. The new code path tries to widen i8
shuffles to i16 shuffles in a splat-like way. There are still some
inefficiencies in our i16 splat logic though, so we aren't really done
here.
Also, for certain patterns (bit of a gather-and-splat) we still
generate pretty silly code, and I've left a fixme for addressing it.
However, I'm not actually worried about this code pattern as much. The
old shuffle lowering generates a 29 instruction monstrosity for it that
should execute much more slowly.
Justin Bogner [Fri, 27 Jun 2014 20:41:25 +0000 (20:41 +0000)]
llvm-cov: Support specifying multiple source files
Make llvm-cov compatible with gcov for cases where multiple files are
specified on the command line. That is, loop over each one and report
coverage, and report errors on stderr only rather than via return
code.
Lang Hames [Fri, 27 Jun 2014 20:20:57 +0000 (20:20 +0000)]
[RuntimeDyld] Add a framework for testing relocation logic in RuntimeDyld.
This patch adds a "-verify" mode to the llvm-rtdyld utility. In verify mode,
llvm-rtdyld will test supplied expressions against the linked program images
that it creates in memory. This scheme can be used to verify the correctness
of the relocation logic applied by RuntimeDyld.
The expressions to test will be read out of files passed via the -check option
(there may be more than one of these). Expressions to check are extracted from
lines of the form:
# rtdyld-check: <expression>
This system is designed to fit the llvm-lit regression test workflow. It is
format and target agnostic, and supports verification of images linked for
remote targets. The expression language is defined in
llvm/include/llvm/RuntimeDyldChecker.h . Examples can be found in
test/ExecutionEngine/RuntimeDyld.
Chandler Carruth [Fri, 27 Jun 2014 20:07:40 +0000 (20:07 +0000)]
[x86] Fix another bug hit when bootstrapping with the new shuffle
lowering.
For maximum irony, I had already discovered this bug, diagnosed it, and
left FIXMEs about it in the test cases. =[ I just failed to go back over
those until after i had reduced a bootstrap miscompile down to a single
TU, stared at the assembly for an hour, and figured out the bug. Again.
Aaron Ballman [Fri, 27 Jun 2014 19:05:17 +0000 (19:05 +0000)]
Adding some trailing whitespace after a comment previously ending with \ to ensure that it isn't lexed as a multiline comment. This silences some -Wcomment warnings.
David Majnemer [Fri, 27 Jun 2014 18:19:56 +0000 (18:19 +0000)]
IR: Add COMDATs to the IR
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.
Reid Kleckner [Fri, 27 Jun 2014 18:17:30 +0000 (18:17 +0000)]
cmake: Don't do anything for LLVM_ENABLE_ASSERTIONS=OFF
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.
Julien Lerouge [Fri, 27 Jun 2014 18:02:54 +0000 (18:02 +0000)]
lldb can interrupt waitpid, so EINTR shouldn't be an error. This fixes the case
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.
David Majnemer [Fri, 27 Jun 2014 17:19:44 +0000 (17:19 +0000)]
MC: Fix associative sections on COFF
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.
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.
Chandler Carruth [Fri, 27 Jun 2014 11:40:13 +0000 (11:40 +0000)]
[x86] Teach the target combine step to aggressively fold pshufd insturcions.
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.
Chandler Carruth [Fri, 27 Jun 2014 11:34:40 +0000 (11:34 +0000)]
[x86] Teach the target-specific combining how to aggressively fold
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.
Chandler Carruth [Fri, 27 Jun 2014 11:27:52 +0000 (11:27 +0000)]
[x86] Teach the X86 backend to DAG-combine SSE2 shuffles that are
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.
Chandler Carruth [Fri, 27 Jun 2014 11:23:44 +0000 (11:23 +0000)]
[x86] Begin a significant overhaul of how vector lowering is done in the
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.
Ulrich Weigand [Fri, 27 Jun 2014 10:32:14 +0000 (10:32 +0000)]
[RuntimeDyld, PowerPC] Fix/improve handling of TOC relocations
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).