The new shuffle lowering has been the default for some time. I've
enabled the new legality testing by default with no really blocking
regressions. I've fuzz tested this very heavily (many millions of fuzz
test cases have passed at this point). And this cleans up a ton of code.
=]
Thanks again to the many folks that helped with this transition. There
was a lot of work by others that went into the new shuffle lowering to
make it really excellent.
In case you aren't using a diff algorithm that can handle this:
X86ISelLowering.cpp: 22 insertions(+), 2940 deletions(-)
llvm-svn: 229964
is going well, remove the flag and the code for the old legality tests.
This is the first step toward removing the entire old vector shuffle
lowering. *Much* more code to delete coming up next.
llvm-svn: 229963
reflects the fact that the x86 backend can in fact lower any shuffle you
want it to with reasonably high code quality.
My recent work on the new vector shuffle has made this regress *very*
little. The diff in the test cases makes me very, very happy.
llvm-svn: 229958
This re-applies r223862, r224198, r224203, and r224754, which were
reverted in r228129 because they exposed Clang misalignment problems
when self-hosting.
The combine caused the crashes because we turned ISD::LOAD/STORE nodes
to ARMISD::VLD1/VST1_UPD nodes. When selecting addressing modes, we
were very lax for the former, and only emitted the alignment operand
(as in "[r1:128]") when it was larger than the standard alignment of
the memory type.
However, for ARMISD nodes, we just used the MMO alignment, no matter
what. In our case, we turned ISD nodes to ARMISD nodes, and this
caused the alignment operands to start being emitted.
And that's how we exposed alignment problems that were ignored before
(but I believe would have been caught with SCTRL.A==1?).
To fix this, we can just mirror the hack done for ISD nodes: only
take into account the MMO alignment when the access is overaligned.
Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
rdar://19717869, rdar://14062261.
llvm-svn: 229932
In preparation for a future patch:
- rename isLoad to isLoadOp: the former is confusing, and can be taken
to refer to the fact that the node is an ISD::LOAD. (it isn't, yet.)
- change formatting here and there.
- add some comments.
- const-ify bools.
llvm-svn: 229929
systematic lowering of v8i16.
This required a slight strategy shift to prefer unpack lowerings in more
places. While this isn't a cut-and-dry win in every case, it is in the
overwhelming majority. There are only a few places where the old
lowering would probably be a touch faster, and then only by a small
margin.
In some cases, this is yet another significant improvement.
llvm-svn: 229859
addition to lowering to trees rooted in an unpack.
This saves shuffles and or registers in many various ways, lets us
handle another class of v4i32 shuffles pre SSE4.1 without domain
crosses, etc.
llvm-svn: 229856
terribly complex partial blend logic.
This code path was one of the more complex and bug prone when it first
went in and it hasn't faired much better. Ultimately, with the simpler
basis for unpack lowering and support bit-math blending, this is
completely obsolete. In the worst case without this we generate
different but equivalent instructions. However, in many cases we
generate much better code. This is especially true when blends or pshufb
is available.
This does expose one (minor) weakness of the unpack lowering that I'll
try to address.
In case you were wondering, this is actually a big part of what I've
been trying to pull off in the recent string of commits.
llvm-svn: 229853
needed, and significantly improve the SSSE3 path.
This makes the new strategy much more clear. If we can blend, we just go
with that. If we can't blend, we try to permute into an unpack so
that we handle cases where the unpack doing the blend also simplifies
the shuffle. If that fails and we've got SSSE3, we now call into
factored-out pshufb lowering code so that we leverage the fact that
pshufb can set up a blend for us while shuffling. This generates great
code, especially because we *know* we don't have a fast blend at this
point. Finally, we fall back on decomposing into permutes and blends
because we do at least have a bit-math-based blend if we need to use
that.
This pretty significantly improves some of the v8i16 code paths. We
never need to form pshufb for the single-input shuffles because we have
effective target-specific combines to form it there, but we were missing
its effectiveness in the blends.
llvm-svn: 229851
them into permutes and a blend with the generic decomposition logic.
This works really well in almost every case and lets the code only
manage the expansion of a single input into two v8i16 vectors to perform
the actual shuffle. The blend-based merging is often much nicer than the
pack based merging that this replaces. The only place where it isn't we
end up blending between two packs when we could do a single pack. To
handle that case, just teach the v2i64 lowering to handle these blends
by digging out the operands.
With this we're down to only really random permutations that cause an
explosion of instructions.
llvm-svn: 229849
v16i8 shuffles, and replace it with new facilities.
This uses precise patterns to match exact unpacks, and the new
generalized unpack lowering only when we detect a case where we will
have to shuffle both inputs anyways and they terminate in exactly
a blend.
This fixes all of the blend horrors that I uncovered by always lowering
blends through the vector shuffle lowering. It also removes *sooooo*
much of the crazy instruction sequences required for v16i8 lowering
previously. Much cleaner now.
The only "meh" aspect is that we sometimes use pshufb+pshufb+unpck when
it would be marginally nicer to use pshufb+pshufb+por. However, the
difference there is *tiny*. In many cases its a win because we re-use
the pshufb mask. In others, we get to avoid the pshufb entirely. I've
left a FIXME, but I'm dubious we can really do better than this. I'm
actually pretty happy with this lowering now.
For SSE2 this exposes some horrors that were really already there. Those
will have to fixed by changing a different path through the v16i8
lowering.
llvm-svn: 229846
on things not being marked as either custom or legal, but we now do
custom lowering of more VSELECT nodes. To cope with this, manually
replicate the legality tests here. These have to stay in sync with the
set of tests used in the custom lowering of VSELECT.
Ideally, we wouldn't do any of this combine-based-legalization when we
have an actual custom legalization step for VSELECT, but I'm not going
to be able to rewrite all of that today.
I don't have a test case for this currently, but it was found when
compiling a number of the test-suite benchmarks. I'll try to reduce
a test case and add it.
This should at least fix the test-suite fallout on build bots.
llvm-svn: 229844
lowering paths. I'm going to be leveraging this to simplify a lot of the
overly complex lowering of v8 and v16 shuffles in pre-SSSE3 modes.
Sadly, this isn't profitable on v4i32 and v2i64. There, the float and
double blending instructions for pre-SSE4.1 are actually pretty good,
and we can't beat them with bit math. And once SSE4.1 comes around we
have direct blending support and this ceases to be relevant.
Also, some of the test cases look odd because the domain fixer
canonicalizes these to floating point domain. That's OK, it'll use the
integer domain when it matters and some day I may be able to update
enough of LLVM to canonicalize the other way.
This restores almost all of the regressions from teaching x86's vselect
lowering to always use vector shuffle lowering for blends. The remaining
problems are because the v16 lowering path is still doing crazy things.
I'll be re-arranging that strategy in more detail in subsequent commits
to finish recovering the performance here.
llvm-svn: 229836
First, don't combine bit masking into vector shuffles (even ones the
target can handle) once operation legalization has taken place. Custom
legalization of vector shuffles may exist for these patterns (making the
predicate return true) but that custom legalization may in some cases
produce the exact bit math this matches. We only really want to handle
this prior to operation legalization.
However, the x86 backend, in a fit of awesome, relied on this. What it
would do is mark VSELECTs as expand, which would turn them into
arithmetic, which this would then match back into vector shuffles, which
we would then lower properly. Amazing.
Instead, the second change is to teach the x86 backend to directly form
vector shuffles from VSELECT nodes with constant conditions, and to mark
all of the vector types we support lowering blends as shuffles as custom
VSELECT lowering. We still mark the forms which actually support
variable blends as *legal* so that the custom lowering is bypassed, and
the legal lowering can even be used by the vector shuffle legalization
(yes, i know, this is confusing. but that's how the patterns are
written).
This makes the VSELECT lowering much more sensible, and in fact should
fix a bunch of bugs with it. However, as you'll see in the test cases,
right now what it does is point out the *hilarious* deficiency of the
new vector shuffle lowering when it comes to blends. Fortunately, my
very next patch fixes that. I can't submit it yet, because that patch,
somewhat obviously, forms the exact and/or pattern that the DAG combine
is matching here! Without this patch, teaching the vector shuffle
lowering to produce the right code infloops in the DAG combiner. With
this patch alone, we produce terrible code but at least lower through
the right paths. With both patches, all the regressions here should be
fixed, and a bunch of the improvements (like using 2 shufps with no
memory loads instead of 2 andps with memory loads and an orps) will
stay. Win!
There is one other change worth noting here. We had hilariously wrong
vectorization cost estimates for vselect because we fell through to the
code path that assumed all "expand" vector operations are scalarized.
However, the "expand" lowering of VSELECT is vector bit math, most
definitely not scalarized. So now we go back to the correct if horribly
naive cost of "1" for "not scalarized". If anyone wants to add actual
modeling of shuffle costs, that would be cool, but this seems an
improvement on its own. Note the removal of 16 and 32 "costs" for doing
a blend. Even in SSE2 we can blend in fewer than 16 instructions. ;] Of
course, we don't right now because of OMG bad code, but I'm going to fix
that. Next patch. I promise.
llvm-svn: 229835
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
Differential Revision: http://reviews.llvm.org/D7065
llvm-svn: 229831
A null MCTargetStreamer allows IRObjectFile to ignore target-specific
directives. Previously we were crashing.
Differential Revision: http://reviews.llvm.org/D7711
llvm-svn: 229797
This involved moving two non-subtarget dependent features (64-bitness
and the driver interface) to the NVPTX target machine and updating
the uses (or migrating around the subtarget use for ease of review).
Otherwise use the cached subtarget or create a default subtarget
based on the TargetMachine cpu and feature string for the module
level assembler emission.
llvm-svn: 229785
VOP2 declares vsrc1, but VOP3 declares src1.
We can't use the same "ins" if the operands have different names in VOP2
and VOP3 encodings.
This fixes a hang in geometry shaders which spill M0 on VI.
(BTW it doesn't look like M0 needs spilling and the spilling seems
duplicated 3 times)
llvm-svn: 229752
Summary:
These ISA's didn't add any instructions so they are almost identical to
Mips32r2 and Mips64r2. Even the ELF e_flags are the same, However the ISA
revision in .MIPS.abiflags is 3 or 5 respectively instead of 2.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: tomatabacu, llvm-commits, atanasyan
Differential Revision: http://reviews.llvm.org/D7381
llvm-svn: 229695
Summary:
Parse for an MCExpr instead of an Identifier and use the symbol for relocations, not just the symbol's name.
This fixes errors when using local labels in .cpsetup (PR22518).
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: seanbruno, emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D7697
llvm-svn: 229671
quite literally the same work, we just need to special case the >64-bit
element shift code emission to emit the byte shift instructions and
offsets. This also makes reasoning about each of the vector lowering
strategies easier as we don't have to remember to use both forms.
llvm-svn: 229662
Add some of the missing M and R class Cortex CPUs, namely:
Cortex-M0+ (called Cortex-M0plus for GCC compatibility)
Cortex-M1
SC000
SC300
Cortex-R5
llvm-svn: 229660
Removed (unreachable) default case in switch to clean up warning:
lib/Target/SystemZ/SystemZISelLowering.cpp:1974:5:
error: default label in switch which covers all enumeration values
[-Werror,-Wcovered-switch-default]
llvm-svn: 229658
code.
While this didn't have the miscompile (it used MatchLeft consistently)
it missed some cases where it could use right shifts. I've added a test
case Craig Topper came up with to exercise the right shift matching.
This code is really identical between the two. I'm going to merge them
next so that we don't keep two copies of all of this logic.
llvm-svn: 229655
The current SystemZ back-end only supports the local-exec TLS access model.
This patch adds all required CodeGen support for the other TLS models, which
means in particular:
- Expand initial-exec TLS accesses by loading TLS offsets from the GOT
using @indntpoff relocations.
- Expand general-dynamic and local-dynamic accesses by generating the
appropriate calls to __tls_get_offset. Note that this routine has
a non-standard ABI and requires loading the GOT pointer into %r12,
so the patch also adds support for the GLOBAL_OFFSET_TABLE ISD node.
- Add a new platform-specific optimization pass to remove redundant
__tls_get_offset calls in the local-dynamic model (modeled after
the corresponding X86 pass).
- Add test cases verifying all access models and optimizations.
llvm-svn: 229654
The current SystemZ back-end only supports the local-exec TLS access model.
This patch adds all required MC support for the other TLS models, which
means in particular:
- Support additional relocation types for
Initial-exec model: R_390_TLS_IEENT
Local-dynamic-model: R_390_TLS_LDO32, R_390_TLS_LDO64,
R_390_TLS_LDM32, R_390_TLS_LDM64, R_390_TLS_LDCALL
General-dynamic model: R_390_TLS_GD32, R_390_TLS_GD64, R_390_TLS_GDCALL
- Support assembler syntax to generate additional relocations
for use with __tls_get_offset calls:
:tls_gdcall:
:tls_ldcall:
The patch also adds a new test to verify fixups and relocations,
and removes the (already unused) FK_390_PLT16DBL/FK_390_PLT32DBL
fixup kinds.
llvm-svn: 229652
track state.
I didn't like this in the code review because the pattern tends to be
error prone, but I didn't see a clear way to rewrite it. Turns out that
there were bugs here, I found them when fuzz testing our shuffle
lowering for correctness on x86.
The core of the problem is that we need to consistently test all our
preconditions for the same directionality of shift and the same input
vector. Instead, formulate this as two predicates (one doesn't depend on
the input in any way), pass things like the directionality and input
vector as inputs, and loop over the alternatives.
This fixes a pattern of very rare miscompiles coming out of this code.
Turned up roughly 4 out of every 1 million v8 shuffles in my fuzz
testing. The new code is over half a million test runs with no failures
yet. I've also fuzzed every other function in the lowering code with
over 3.5 million test cases and not discovered any other miscompiles.
llvm-svn: 229642
Some formats capitalized these, but most didn't. Change
them all to be consistently lowercase.
Now, non-encoding fields and convenience bits are capitalized.
Also remove weird looking empty line in some of the formats.
llvm-svn: 229613
initialization. Initialize the subtarget once per function and
migrate EmitStartOfAsmFile to either use calls on the
TargetMachine or get information from the subtarget we'd use
for assembling.
The top-level-ness of the MIPS attribute output for assembly is,
by nature, contrary to how we'd want to do this for an LTO
situation where we have multiple cpu architectures so this
solution is good enough for now.
llvm-svn: 229596
This patch teaches fast-isel how to select a (V)CVTSI2SSrr for an integer to
float conversion, and how to select a (V)CVTSI2SDrr for an integer to double
conversion.
Added test 'fast-isel-int-float-conversion.ll'.
Differential Revision: http://reviews.llvm.org/D7698
llvm-svn: 229589
The problem in the original patch was not switching back to .text after printing
an eh table.
Original message:
On ELF, put PIC jump tables in a non executable section.
Fixes PR22558.
llvm-svn: 229586
Change the memory operands in sse12_fp_packed_scalar_logical_alias from scalars to vectors.
That's what the hardware packed logical FP instructions define: 128-bit memory operands.
There are no scalar versions of these instructions...because this is x86.
Generating the wrong code (folding a scalar load into a 128-bit load) is still possible
using the peephole optimization pass and the load folding tables. We won't completely
solve this bug until we either fix the lowering in fabs/fneg/fcopysign and any other
places where scalar FP logic is created or fix the load folding in foldMemoryOperandImpl()
to make sure it isn't changing the size of the load.
Differential Revision: http://reviews.llvm.org/D7474
llvm-svn: 229531
initialization. Initialize the subtarget once per function and
migrate Emit{Start|End}OfAsmFile to either use attributes on the
TargetMachine or get information from the subtarget we'd use
for assembling. One bit (getISAEncoding) touched the general
AsmPrinter and the debug output. Handle this one by passing
the function for the subprogram down and updating all callers
and users.
The top-level-ness of the ARM attribute output for assembly is,
by nature, contrary to how we'd want to do this for an LTO
situation where we have multiple cpu architectures so this
solution is good enough for now.
llvm-svn: 229528
GCC 4.8 reported two new warnings due to comparisons
between signed and unsigned integer expressions. The new warnings were
accidentally introduced by revision 229480.
Added explicit casts to silence the warnings. No functional change intended.
llvm-svn: 229488
- added mask types v8i1 and v16i1 to possible function parameters
- enabled passing 512-bit vectors in standard CC
- added a test for KNL intel_ocl_bi conventions
llvm-svn: 229482
Vector zext tends to get legalized into a vector anyext, represented as a vector shuffle with an undef vector + a bitcast, that gets ANDed with a mask that zeroes the undef elements.
Combine this into an explicit shuffle with a zero vector instead. This allows shuffle lowering to match it as a zext, instead of matching it as an anyext and emitting an explicit AND.
This combine only covers a subset of the cases, but it's a start.
Differential Revision: http://reviews.llvm.org/D7666
llvm-svn: 229480
initialization. Initialize the subtarget once per function and
migrate EmitStartOfAsmFile to either use attributes on the
TargetMachine or get information from all of the various
subtargets.
llvm-svn: 229475
This allows it to match still more places where previously we would have
to fall back on floating point shuffles or other more complex lowering
strategies.
I'm hoping to replace some of the hand-rolled unpack matching with this
routine is it gets more and more clever.
llvm-svn: 229463
Our register allocation has become better recently, it seems, and is now
starting to generate cross-block copies into inflated register classes. These
copies are not transformed into subregister insertions/extractions by the
PPCVSXCopy class, and so need to be handled directly by
PPCInstrInfo::copyPhysReg. The code to do this was *almost* there, but not
quite (it was unnecessarily restricting itself to only the direct
sub/super-register-class case (not copying between, for example, something in
VRRC and the lower-half of VSRC which are super-registers of F8RC).
Triggering this behavior manually is difficult; I'm including two
bugpoint-reduced test cases from the test suite.
llvm-svn: 229457
Chandler Carruth