We swapped the operands and used setle, but I don't see any reason to do that. I think this is a holdover from SSE where we swap and the invert to use pcmpgt. But with AVX512 we don't want an invert so we won't use pcmpgt. So there's no need to swap.
llvm-svn: 325527
Previously we used the immediate encoding if the load was in operand 0 and the short encoding if the load was in operand 1.
This added an insane number of bytes to the size of the isel table. I'm wondering if we should always use the immediate form during isel and change to the short form during emission. This would remove the need to pattern match every combination for both the immediate form and the short form during isel. We could do the same with vpcmpgt
llvm-svn: 325456
Undef VLX, getSetCCResultType returns v2i1/v4i1 for v2f32/v4f32 so default type legalization will end up changing the setcc result type back to vXi1 if it had been extended. The resulting extend gets messed up further by type legalization and is difficult to recombine back to (v4i32 (setcc (v4f32))) after legalization.
I went ahead and enabled this for SSE2 and later since its always the result we want and this helps type legalization get there in less steps.
llvm-svn: 324822
This avoids a constant pool load to create 1.
The int->float are showing converts to mask and back. We probably need to widen inputs to sint_to_fp/uint_to_fp before type legalization.
llvm-svn: 324805
Discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html
In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.
llvm-svn: 323922
We can use the same input for both operands to get a free compare with zero.
We already use this trick in a couple places where we explicitly create PTESTM with the same input twice. This generalizes it.
I'm hoping to remove the ISD opcodes and move this to isel patterns like we do for scalar cmp/test.
llvm-svn: 323605
Summary:
For the most part its better to keep v32i1 as a mask type of a narrower width than trying to promote it to a ymm register.
I had to add some overrides to the methods that get the types for the calling convention so that we still use v32i8 for argument/return purposes.
There are still some regressions in here. I definitely saw some around shuffles. I think we probably should move vXi1 shuffle from lowering to a DAG combine where I think the extend and truncate we have to emit would be better combined.
I think we also need a DAG combine to remove trunc from (extract_vector_elt (trunc))
Overall this removes something like 13000 CHECK lines from lit tests.
Reviewers: zvi, RKSimon, delena, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42031
llvm-svn: 323201
Extend vXi1 conditions of vXi8/vXi16 selects even before type legalization gets a chance to split wide vectors. Previously we would only extend 128 and 256 bit vectors. But if we start with a 512 bit vector or wider that needs to be split we wouldn't extend until after the split had taken place. By extending early we improve the results of type legalization.
Don't widen condition of 128/256 bit vXi16/vXi8 selects when we have BWI but not VLX. We can still use a mask register by widening the select to 512-bits instead. This is similar to what we do for compares already.
llvm-svn: 322450
Additional test cases cover selects with i16/i8 conditions that are only 128/256-bits wide, but the compares are 512-bits wide and can only produce k-registers. We should be able to artificially widen the selects to avoid moving the k-register to an xmm/ymm register.
llvm-svn: 322449
Normally target independent DAG combine would do this combine based on getSetCCResultType, but with VLX getSetCCResultType returns a vXi1 type preventing the DAG combining from kicking in.
But doing this combine can allow us to remove the explicit sign extend that would otherwise be emitted.
This patch adds a target specific DAG combine to combine the sext+setcc when the result type is the same size as the input to the setcc. I've restricted this to FP compares and things that can be represented with PCMPEQ and PCMPGT since we don't have full integer compare support on the older ISAs.
Differential Revision: https://reviews.llvm.org/D41850
llvm-svn: 322101
Summary:
There are few oddities that occur due to v1i1, v8i1, v16i1 being legal without v2i1 and v4i1 being legal when we don't have VLX. Particularly during legalization of v2i32/v4i32/v2i64/v4i64 masked gather/scatter/load/store. We end up promoting the mask argument to these during type legalization and then have to widen the promoted type to v8iX/v16iX and truncate it to get the element size back down to v8i1/v16i1 to use a 512-bit operation. Since need to fill the upper bits of the mask we have to fill with 0s at the promoted type.
It would be better if we could just have the v2i1/v4i1 types as legal so they don't undergo any promotion. Then we can just widen with 0s directly in a k register. There are no real v4i1/v2i1 instructions anyway. Everything is done on a larger register anyway.
This also fixes an issue that we couldn't implement a masked vextractf32x4 from zmm to xmm properly.
We now have to support widening more compares to 512-bit to get a mask result out so new tablegen patterns got added.
I had to hack the legalizer for widening the operand of a setcc a bit so it didn't try create a setcc returning v4i32, extract from it, then try to promote it using a sign extend to v2i1. Now we create the setcc with v4i1 if the original setcc's result type is v2i1. Then extract that and don't sign extend it at all.
There's definitely room for improvement with some follow up patches.
Reviewers: RKSimon, zvi, guyblank
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41560
llvm-svn: 321967
A v32i1 CONCAT_VECTORS of v16i1 uses promotion to v32i8 to legalize the v32i1. This results in a bunch of extract_vector_elts and a build_vector that ultimately gets scalarized.
This patch checks to see if v16i8 is legal and inserts a any_extend to that so that we can concat v16i8 to v32i8 and avoid creating the extracts.
llvm-svn: 320674
Previously we used a wider element type and truncated. But its more efficient to keep the element type and drop unused elements.
If BWI isn't supported and we have a i16 or i8 type, we'll extend it to be i32 and still use a truncate.
llvm-svn: 319740
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.
The MIR printer prints the IR name of a MBB only for block definitions.
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix
Differential Revision: https://reviews.llvm.org/D40422
llvm-svn: 319665
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.
* Only debug printing is affected. It now follows MIR.
Differential Revision: https://reviews.llvm.org/D40417
llvm-svn: 319187
For cases where we know the floating point representations match the bitcasted integer equivalent, allow bitcasting to these types.
This is especially useful for the X86 floating point compare results which return all/zero bits but as a floating point type.
Differential Revision: https://reviews.llvm.org/D39289
llvm-svn: 316831
NFC.
Updated 8 regression tests to use -mattr instead of -mcpu flag as follows:
-mcpu=knl --> -mattr=+avx512f
-mcpu=skx --> -mattr=+avx512f,+avx512bw,+avx512vl,+avx512dq
The updates are as part of the preparation of a large commit to add all instruction scheduling for the SKX target.
Reviewers: delena, zvi, RKSimon
Differential Revision: https://reviews.llvm.org/D38222
Change-Id: I2381c9b5bb75ecacfca017243c22d054f6eddd14
llvm-svn: 314306
This patch completely replaces the instruction scheduling information for the Haswell architecture target by modifying the file X86SchedHaswell.td located under the X86 Target.
We used the scheduling information retrieved from the Haswell architects in order to replace and modify the existing scheduling.
The patch continues the scheduling replacement effort started with the SNB target in r307529 and r310792.
Information includes latency, number of micro-Ops and used ports by each HSW instruction.
Please expect some performance fluctuations due to code alignment effects.
Reviewers: RKSimon, zvi, aymanmus, craig.topper, m_zuckerman, igorb, dim, chandlerc, aaboud
Differential Revision: https://reviews.llvm.org/D36663
llvm-svn: 311879
This is NFC after rerunning the "update_llc_test_checks.py" tool on the CodeGen X86 tests in order to submit a patch.
Minor differences due to added "End of Function" lines.
Reviewers: zvi
Differential Revision: https://reviews.llvm.org/D34933
llvm-svn: 306973
•static latency
•number of uOps from which the instructions consists
•all ports used by the instruction
Reviewers:
RKSimon
zvi
aymanmus
m_zuckerman
Differential Revision: https://reviews.llvm.org/D33897
llvm-svn: 306414
We've had several bugs(PR32256, PR32241) recently that resulted from usages of AH/BH/CH/DH either before or after a copy to/from a mask register.
This ultimately occurs because we create COPY_TO_REGCLASS with VK1 and GR8. Then in CopyToFromAsymmetricReg in X86InstrInfo we find a 32-bit super register for the GR8 to emit the KMOV with. But as these tests are demonstrating, its possible for the GR8 register to be a high register and we end up doing an accidental extra or insert from bits 15:8.
I think the best way forward is to stop making copies directly between mask registers and GR8/GR16. Instead I think we should restrict to only copies between mask registers and GR32/GR64 and use EXTRACT_SUBREG/INSERT_SUBREG to handle the conversion from GR32 to GR16/8 or vice versa.
Unfortunately, this complicates fastisel a bit more now to create the subreg extracts where we used to create GR8 copies. We can probably make a helper function to bring down the repitition.
This does result in KMOVD being used for copies when BWI is available because we don't know the original mask register size. This caused a lot of deltas on tests because we have to split the checks for KMOVD vs KMOVW based on BWI.
Differential Revision: https://reviews.llvm.org/D30968
llvm-svn: 298928
VZEROUPPER should not be issued on Knights Landing (KNL), but on Skylake-avx512 it should be.
Differential Revision: https://reviews.llvm.org/D29874
llvm-svn: 296859
During legalization we are often creating shuffles (via a build_vector scalarization stage) that are "any_extend_vector_inreg" style masks, and also other masks that are the equivalent of "truncate_vector_inreg" (if we had such a thing).
This patch is an attempt to match these cases to help undo the effects of just leaving shuffle lowering to handle it - which typically means we lose track of the undefined elements of the shuffles resulting in an unnecessary extension+truncation stage for widened illegal types.
The 2011-10-21-widen-cmp.ll regression will be fixed by making SIGN_EXTEND_VECTOR_IN_REG legal in SSE instead of lowering them to X86ISD::VSEXT (PR31712).
Differential Revision: https://reviews.llvm.org/D29454
llvm-svn: 295451
Isel now selects masked move instructions for vselect instead of blendm. But sometimes it beneficial to register allocation to remove the tied register constraint by using blendm instructions.
This also picks up cases where the masked move was created due to a masked load intrinsic.
Differential Revision: https://reviews.llvm.org/D28454
llvm-svn: 292005
We should probably teach the two address instruction pass to turn masked moves into BLENDM when its beneficial to the register allocator.
llvm-svn: 291371
There are cases of AVX-512 instructions that have two possible encodings. This is the case with instructions that use vector registers with low indexes of 0 - 15 and do not use the zmm registers or the mask k registers.
The EVEX encoding prefix requires 4 bytes whereas the VEX prefix can take only up to 3 bytes. Consequently, using the VEX encoding for these instructions results in a code size reduction of ~2 bytes even though it is compiled with the AVX-512 features enabled.
Reviewers: Craig Topper, Zvi Rackoover, Elena Demikhovsky
Differential Revision: https://reviews.llvm.org/D27901
llvm-svn: 290663
adding new optimization opportunity by adding new X86ISelLowering pattern. The test case was shown in https://llvm.org/bugs/show_bug.cgi?id=30945.
Test explanation:
Select gets three arguments mask, op and op2. In this case, the Mask is a result of ICMP. The ICMP instruction compares (with equal operand) the zero initializer vector and the result of the first ICMP.
In general, The result of "cmp eq, op1, zero initializers" is "not(op1)" where op1 is a mask. By rearranging of the two arguments inside the Select instruction, we can get the same result. Without the necessary of the middle phase ("cmp eq, op1, zero initializers").
Missed optimization opportunity:
vpcmpled %zmm0, %zmm1, %k0
knotw %k0, %k1
can be combine to
vpcmpgtd %zmm0, %zmm2, %k1
Reviewers:
1. delena
2. igorb
Commited after check all
Differential Revision: https://reviews.llvm.org/D27160
llvm-svn: 289653
Fixed an issue with vector usage of TargetLowering::isConstTrueVal / TargetLowering::isConstFalseVal boolean result matching.
The comment said we shouldn't handle constant splat vectors with undef elements. But the the actual code was returning false if the build vector contained no undef elements....
This patch now ignores the number of undefs (getConstantSplatNode will return null if the build vector is all undefs).
The change has also unearthed a couple of missed opportunities in AVX512 comparison code that will need to be addressed.
Differential Revision: https://reviews.llvm.org/D26031
llvm-svn: 286238
The previous implementation (not custom) doesn't enforce zeroing off upper bits. The assumption is that i1 PRODUCER (truncate and extractelement) must zero all upper bits, so i1 CONSUMER instructions ( test, zext, save, etc) can be done without additional zeroing.
Make extractelement i1 lowering custom for all vector i1.
Differential Revision: http://reviews.llvm.org/D23246
llvm-svn: 278328
Optimized lowering of BITCAST node. The BITCAST node can be replaced with COPY_TO_REG instead of KMOV.
It allows to suppress two opposite BITCAST operations and avoid redundant "movs".
Differential Revision: https://reviews.llvm.org/D23247
llvm-svn: 277958
We know that pcmp produces all-ones/all-zeros bitmasks, so we can use that behavior to avoid unnecessary constant loading.
One could argue that load+and is actually a better solution for some CPUs (Intel big cores) because shifts don't have the
same throughput potential as load+and on those cores, but that should be handled as a CPU-specific later transformation if
it ever comes up. Removing the load is the more general x86 optimization. Note that the uneven usage of vpbroadcast in the
test cases is filed as PR28505:
https://llvm.org/bugs/show_bug.cgi?id=28505
Differential Revision: http://reviews.llvm.org/D22225
llvm-svn: 275276
An identity COPY like this:
%AL = COPY %AL, %EAX<imp-def>
has no semantic effect, but encodes liveness information: Further users
of %EAX only depend on this instruction even though it does not define
the full register.
Replace the COPY with a KILL instruction in those cases to maintain this
liveness information. (This reverts a small part of r238588 but this
time adds a comment explaining why a KILL instruction is useful).
llvm-svn: 274952
