The contract of this function seems problematic (fallback in either
direction seems like it could produce bugs in one client or another),
but here's some tests for its current behavior, at least. See the
commit/review thread of r218187 for more discussion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218626 91177308-0d34-0410-b5e6-96231b3b80d8
This takes a single argument convertible to T, and
- if the Optional has a value, returns the existing value,
- otherwise, constructs a T from the argument and returns that.
Inspired by std::experimental::optional from the "Library Fundamentals" C++ TS.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218618 91177308-0d34-0410-b5e6-96231b3b80d8
These turn into fadds, so combine them into the target
mad node.
fadd (fadd (a, a), b) -> mad 2.0, a, b
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218608 91177308-0d34-0410-b5e6-96231b3b80d8
This patch improves the target-specific cost model to better handle signed
division by a power of two. The immediate result is that this enables the SLP
vectorizer to do a better job.
http://reviews.llvm.org/D5469
PR20714
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218607 91177308-0d34-0410-b5e6-96231b3b80d8
There will be multiple TypeUnits in an unlinked object that will be extracted
from different sections. Now that we have DWARFUnitSection that is supposed
to represent an input section, we need a DWARFUnitSection<TypeUnit> per
input .debug_types section.
Once this is done, the interface is homogenous and we can move the Section
parsing code into DWARFUnitSection.
This is a respin of r218513 that got reverted because it broke some builders.
This new version features an explicit move constructor for the DWARFUnitSection
class to workaround compilers unable to generate correct C++11 default
constructors.
Reviewers: samsonov, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5482
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218606 91177308-0d34-0410-b5e6-96231b3b80d8
Runtime unrolling will create a prologue to execute the extra
iterations which is can't divided by the unroll factor. It
generates an if-then-else sequence to jump into a factor -1
times unrolled loop body, like
extraiters = tripcount % loopfactor
if (extraiters == 0) jump Loop:
if (extraiters == loopfactor) jump L1
if (extraiters == loopfactor-1) jump L2
...
L1: LoopBody;
L2: LoopBody;
...
if tripcount < loopfactor jump End
Loop:
...
End:
It means if the unroll factor is 4, the loop body will be 7
times unrolled, 3 are in loop prologue, and 4 are in the loop.
This commit is to use a loop to execute the extra iterations
in prologue, like
extraiters = tripcount % loopfactor
if (extraiters == 0) jump Loop:
else jump Prol
Prol: LoopBody;
extraiters -= 1 // Omitted if unroll factor is 2.
if (extraiters != 0) jump Prol: // Omitted if unroll factor is 2.
if (tripcount < loopfactor) jump End
Loop:
...
End:
Then when unroll factor is 4, the loop body will be copied by
only 5 times, 1 in the prologue loop, 4 in the original loop.
And if the unroll factor is 2, new loop won't be created, just
as the original solution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218604 91177308-0d34-0410-b5e6-96231b3b80d8
nodes, and rely exclusively on its logic. This removes a ton of
duplication from the blend lowering and centralizes it in one place.
One downside is that it requires a bunch of hacks to make this work with
the current legalization framework. We have to manually speculate one
aspect of legalizing VSELECT nodes to get everything to work nicely
because the existing legalization framework isn't *actually* bottom-up.
The other grossness is that we somewhat duplicate the analysis of
constant blends. I'm on the fence here. If reviewers thing this would
look better with VSELECT when it has constant operands dumping over tho
VECTOR_SHUFFLE, we could go that way. But it would be a substantial
change because currently all of the actual blend instructions are
matched via patterns in the TD files based around VSELECT nodes (despite
them not being perfect fits for that). Suggestions welcome, but at least
this removes the rampant duplication in the backend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218600 91177308-0d34-0410-b5e6-96231b3b80d8
X86 target-specific DAG combining that tried to convert VSELECT nodes
into VECTOR_SHUFFLE nodes that it "knew" would lower into
immediate-controlled blend nodes.
Turns out, we have perfectly good lowering of all these VSELECT nodes,
and indeed that lowering already knows how to handle lowering through
BLENDI to immediate-controlled blend nodes. The code just wasn't getting
used much because this thing forced the world to go through the vector
shuffle lowering. Yuck.
This also exposes that I was too aggressive in avoiding domain crossing
in v218588 with that lowering -- when the other option is to expand into
two 128-bit vectors, it is worth domain crossing. Restore that behavior
now that we have nice tests covering it.
The test updates here fall into two camps. One is where previously we
ended up with an unsigned encoding of the blend operand and now we get
a signed encoding. In most of those places there were elaborate comments
explaining exactly what these operands really mean. Rather than that,
just switch these tests to use the nicely decoded comments that make it
obvious that the final shuffle matches.
The other updates are just removing pointless domain crossing by
blending integers with PBLENDW rather than BLENDPS.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218589 91177308-0d34-0410-b5e6-96231b3b80d8
crossing and generally work more like the blend emission code in the new
vector shuffle lowering.
My goal is to have the new vector shuffle lowering just produce VSELECT
nodes that are either matched here to BLENDI or are legal and matched in
the .td files to specific blend instructions. That seems much cleaner as
there are other ways to produce a VSELECT anyways. =]
No *observable* functionality changed yet, mostly because this code
appears to be near-dead. The behavior of this lowering routine did
change though. This code being mostly dead and untestable will change
with my next commit which will also point some new tests at it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218588 91177308-0d34-0410-b5e6-96231b3b80d8
AVX-512.
There is no interesting logic yet. Everything ends up eventually
delegating to the generic code to split the vector and shuffle the
halves. Interestingly, that logic does a significantly better job of
lowering all of these types than the generic vector expansion code does.
Mostly, it lets most of the cases fall back to nice AVX2 code rather
than all the way back to SSE code paths.
Step 2 of basic AVX-512 support in the new vector shuffle lowering. Next
up will be to incrementally add direct support for the basic instruction
set to each type (adding tests first).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218585 91177308-0d34-0410-b5e6-96231b3b80d8
assertion, making the name generic, and improving the documentation.
Step 1 in adding very primitive support for AVX-512. No functionality
changed yet.
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vectors.
Someone will need to build the AVX512 lowering, which should follow
AVX1 and AVX2 *very* closely for AVX512F and AVX512BW resp. I've added
a dummy test which is a port of the v8f32 and v8i32 tests from AVX and
AVX2 to v8f64 and v8i64 tests for AVX512F and AVX512BW. Hopefully this
is enough information for someone to implement proper lowering here. If
not, I'll be happy to help, but right now the AVX-512 support isn't
a priority for me.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218583 91177308-0d34-0410-b5e6-96231b3b80d8
lowerings.
This was hopelessly broken. First, the x86 backend wants '-1' to be the
element value representing true in a boolean vector, and second the
operand order for VSELECT is backwards from the actual x86 instructions.
To make matters worse, the backend is just using '-1' as the true value
to get the high bit to be set. It doesn't actually symbolically map the
'-1' to anything. But on x86 this isn't quite how it works: there *only*
the high bit is relevant. As a consequence weird non-'-1' values like
0x80 actually "work" once you flip the operands to be backwards.
Anyways, thanks to Hal for helping me sort out what these *should* be.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218582 91177308-0d34-0410-b5e6-96231b3b80d8
new vector shuffle target DAG combines -- it helps to actually test for
the value you want rather than just using an integer in a boolean
context.
Have I mentioned that I loathe implicit conversions recently? :: sigh ::
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218576 91177308-0d34-0410-b5e6-96231b3b80d8
of widening masks.
We can't widen a zeroing mask unless both elements that would be merged
are either zeroed or undef. This is the only way to widen a mask if it
has a zeroed element.
Also clean up the code here by ordering the checks in a more logical way
and by using the symoblic values for undef and zero. I'm actually torn
on using the symbolic values because the existing code is littered with
the assumption that -1 is undef, and moreover that entries '< 0' are the
special entries. While that works with the values given to these
constants, using the symbolic constants actually makes it a bit more
opaque why this is the case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218575 91177308-0d34-0410-b5e6-96231b3b80d8
If there is a store followed by a store with the same value to the same location, then the store is dead/noop. It can be removed.
This problem is found in spec2006-197.parser.
For example,
stur w10, [x11, #-4]
stur w10, [x11, #-4]
Then one of the two stur instructions can be removed.
Patch by David Xu!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218569 91177308-0d34-0410-b5e6-96231b3b80d8
llvm::huge_valf is defined in a header file, so it is initialized
multiple times in every compiled unit upon program startup.
With non-VC compilers huge_valf is set to a HUGE_VALF which the
compiler can probably optimize out.
With VC numeric_limits<float>::infinity() does not return a number
but a runtime structure member which therotically may change
between calls so the compiler does not optimize out the
initialization and it happens many times. It can be easily seen by
placing a breakpoint on the initialization line.
This patch moves llvm::huge_valf initialization to a source file
instead of the header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218567 91177308-0d34-0410-b5e6-96231b3b80d8
I spotted this by inspection when debugging something else, so I have no
test case what-so-ever, and am not even sure it is possible to
realistically trigger the bug. But this is what was intended here.
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and in the target shuffle combining when trying to widen vector
elements.
Previously only one of these was correct, and we didn't correctly
propagate zeroing target shuffle masks (which have a different sentinel
value from undef in non- target shuffle masks now). This isn't just
a missed optimization, this caused us to drop zeroing shuffles on the
floor and miscompile code. The added test case is one example of that.
There are other fixes to the test suite as a consequence of this as well
as restoring the undef elements in some of the masks that were lost when
I brought sanity to the actual *value* of the undef and zero sentinels.
I've also just cleaned up some of the PSHUFD and PSHUFLW and PSHUFHW
combining code, but that code really needs to go. It was a nice initial
attempt, but it isn't very principled and the recursive shuffle combiner
is much more powerful.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218562 91177308-0d34-0410-b5e6-96231b3b80d8
to significantly more sane sentinels. Notably, everywhere else in the
backend's representation of shuffles uses '-1' to represent undef. The
target shuffle masks really shouldn't diverge from that, especially as
in a few places they are manipulated by shared code.
This causes us to lose some undef lanes in various test masks. I want to
get these back, but technically it isn't invalid and there are a *lot*
of bugs here so I want to try to establish a saner baseline for fixing
some of the bugs by aligning the specific senitnel values used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218561 91177308-0d34-0410-b5e6-96231b3b80d8
This is purely refactoring. No functional changes intended. PowerPC is the only target
that is currently using this interface.
The ultimate goal is to allow targets other than PowerPC (certainly X86 and Aarch64) to turn this:
z = y / sqrt(x)
into:
z = y * rsqrte(x)
And:
z = y / x
into:
z = y * rcpe(x)
using whatever HW magic they can use. See http://llvm.org/bugs/show_bug.cgi?id=20900 .
There is one hook in TargetLowering to get the target-specific opcode for an estimate instruction
along with the number of refinement steps needed to make the estimate usable.
Differential Revision: http://reviews.llvm.org/D5484
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Users of getSectionContents shouldn't try to pass in BSS or virtual
sections. In all instances, this is a bug in the code calling this
routine.
N.B. Some COFF implementations (like CL) will mark their BSS sections as
taking space on disk. This would confuse COFFObjectFile into thinking
the section is larger than the file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218549 91177308-0d34-0410-b5e6-96231b3b80d8
So in fully linked images when a call is made through a stub it now gets a
comment like the following in the disassembly:
callq 0x100000f6c ## symbol stub for: _printf
indicating the call is to a symbol stub and which symbol it is for. This is
done for branch reference types and seeing if the branch target is in a stub
section and if so using the indirect symbol table entry for that stub and
using that symbol table entries symbol name.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218546 91177308-0d34-0410-b5e6-96231b3b80d8
files in this directory. If it should be defined anywhere, it should be defined
when building lib/LTO/LTOCodeGenerator.cpp, but we've not had it defined there
for quite some time, so that doesn't really seem to be very important. (It also
would slow down the modules build by creating extra module variants.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218544 91177308-0d34-0410-b5e6-96231b3b80d8
lldb sets the variable SHARED_LIBRARY to 1, which breaks this conditional,
because older versions of CMake interpret
if ("${t}" STREQUAL "SHARED_LIBRARY")
as meaning
if ("${t}" STREQUAL "1")
in this case. Change the conditional so it does the right thing with both old
and new CMakes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218542 91177308-0d34-0410-b5e6-96231b3b80d8
that managed to elude all of my fuzz testing historically. =/
Something changed to allow this code path to actually be exercised and
it was doing bad things. It is especially heavily exercised by the
patterns that emerge when doing AVX shuffles that end up lowered through
the 128-bit code path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218540 91177308-0d34-0410-b5e6-96231b3b80d8
This has weird operand requirements so it's worthwhile
to have very strict checks for its operands.
Add different combinations of SGPR operands.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218535 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of moving the first SGPR that is different than the first,
legalize the operand that requires the fewest moves if one
SGPR is used for multiple operands.
This saves extra moves and is also required for some instructions
which require that the same operand be used for multiple operands.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218532 91177308-0d34-0410-b5e6-96231b3b80d8