Summary:
Combine unmerge(trunc) to enable other merge combines.
Without this combine, the scalar unmerge(trunc(merge))
pattern cannot be combined and easily lead to
hard-to-legalize merge/unmerge artifacts.
Reviewed By: arsenm
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79567
Currently this code exists in widenScalar for G_MERGE_VALUE
sources. I'm not sure if the existing expansion in widenScalar should
be removed or not. The widenScalar variant tries to extend to the
requested size, but this just uses the original bitwidth.
Summary:
The combine for unmerge(cast(merge)) is only valid for vectors, but was
missing a corresponding check. Add a check that the operands are vectors
to avoid an invalid combine.
Without this check, the combiner would emit incorrect code for scalars
and pointers because the artifact cast (trunc/ext) only affects bits at
the end of the type, while this combine assumes that the casted bits
appear between meaningful bits.
This also uncovered a segmentation fault in the AMDGPU
InstructionSelector. The tests triggering this bug have been moved to
their own file and a check for the segmentation fault has been added.
Reviewers: arsenm, dsanders, aemerson, paquette, aditya_nandakumar
Reviewed By: arsenm
Subscribers: tpr, jvesely, wdng, nhaehnle, rovka, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78191
Summary:
Truncating the result of a merge means that most likely we could have done without merge in the first place and just used the input merge inputs directly. This can be done in three cases:
1. If the truncation result is smaller than the merge source, we can use the source in the trunc directly
2. If the sizes are the same, we can replace the register or use a copy
3. If the truncation size is a multiple of the merge source size, we can build a smaller merge
This gets rid of most of the larger, hard-to-legalize merges.
Reviewers: qcolombet, aditya_nandakumar, aemerson, paquette, arsenm, Petar.Avramovic
Reviewed By: arsenm
Subscribers: sdardis, jvesely, wdng, nhaehnle, rovka, jrtc27, atanasyan, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75915
The legalizer produces a lot of these, and they make reading legalized
MIR annoying. For some reason, this does seem to sometimes introduce
copies of implicit def, which is dumb.
Fix typos. Use Hi and Lo prefixes for Or instead of LHS and RHS
to match names of surrounding variables.
Differential Revision: https://reviews.llvm.org/D66587
llvm-svn: 370062
Extract the sources to the GCD of the original size and target size,
padding with implicit_def as necessary.
Also fix the case where the requested source type is wider than the
original result type. This was ignoring the type, and just using the
destination. Do the operation in the requested type and truncate back.
llvm-svn: 366367
Use an anyext to the requested type for the leftover operand to
produce a slightly wider type, and then truncate the final merge.
I have another implementation almost ready which handles arbitrary
widens, but I think it produces worse code in this example (which I
think is 90% due to not folding redundant copies or folding out
implicit_def users), so I wanted to add this as a baseline first.
llvm-svn: 366366
Apparently the check for legal instructions during instruction
select does not happen without an asserts build, so these would
successfully select in release, and fail in debug.
Make s16 and/or/xor legal. These can just be selected directly
to the 32-bit operation, as is already done in SelectionDAG, so just
make them legal.
llvm-svn: 366210
If the requested source type an be used as a merge source type, create
a merge of merges. This avoids creating large, illegal extensions and
bit-ops directly to the result type.
llvm-svn: 364841
Other opcodes shouldn't be CSE'd until we can be sure debug info quality won't
be degraded.
This change also improves the IRTranslator so that in most places, but not all,
it creates constants using the MIRBuilder directly instead of first creating a
new destination vreg and then creating a constant. By doing this, the
buildConstant() method can just return the vreg of an existing G_CONSTANT
instead of having to create a COPY from it.
I measured a 0.2% improvement in compile time and a 0.9% improvement in code
size at -O0 ARM64.
Compile time:
Program base cse diff
test-suite...ark/tramp3d-v4/tramp3d-v4.test 9.04 9.12 0.8%
test-suite...Mark/mafft/pairlocalalign.test 2.68 2.66 -0.7%
test-suite...-typeset/consumer-typeset.test 5.53 5.51 -0.4%
test-suite :: CTMark/lencod/lencod.test 5.30 5.28 -0.3%
test-suite :: CTMark/Bullet/bullet.test 25.82 25.76 -0.2%
test-suite...:: CTMark/ClamAV/clamscan.test 6.92 6.90 -0.2%
test-suite...TMark/7zip/7zip-benchmark.test 34.24 34.17 -0.2%
test-suite :: CTMark/SPASS/SPASS.test 6.25 6.24 -0.1%
test-suite...:: CTMark/sqlite3/sqlite3.test 1.66 1.66 -0.1%
test-suite :: CTMark/kimwitu++/kc.test 13.61 13.60 -0.0%
Geomean difference -0.2%
Code size:
Program base cse diff
test-suite...-typeset/consumer-typeset.test 1315632 1266480 -3.7%
test-suite...:: CTMark/ClamAV/clamscan.test 1313892 1297508 -1.2%
test-suite :: CTMark/lencod/lencod.test 1439504 1423112 -1.1%
test-suite...TMark/7zip/7zip-benchmark.test 2936980 2904172 -1.1%
test-suite :: CTMark/Bullet/bullet.test 3478276 3445460 -0.9%
test-suite...ark/tramp3d-v4/tramp3d-v4.test 8082868 8033492 -0.6%
test-suite :: CTMark/kimwitu++/kc.test 3870380 3853972 -0.4%
test-suite :: CTMark/SPASS/SPASS.test 1434904 1434896 -0.0%
test-suite...Mark/mafft/pairlocalalign.test 764528 764528 0.0%
test-suite...:: CTMark/sqlite3/sqlite3.test 782092 782092 0.0%
Geomean difference -0.9%
Differential Revision: https://reviews.llvm.org/D60580
llvm-svn: 358369
This is pretty much directly ported from SelectionDAG. Doesn't include
the shift by non-constant but known bits version, since there isn't a
globalisel version of computeKnownBits yet.
This shows a disadvantage of targets not specifically which type
should be used for the shift amount. If type 0 is legalized before
type 1, the operations on the shift amount type use the wider type
(which are also less likely to legalize). This can be avoided by
targets specifying legalization actions on type 1 earlier than for
type 0.
llvm-svn: 353455
This patch restricts the capability of G_MERGE_VALUES, and uses the new
G_BUILD_VECTOR and G_CONCAT_VECTORS opcodes instead in the appropriate places.
This patch also includes AArch64 support for selecting G_BUILD_VECTOR of <4 x s32>
and <2 x s64> vectors.
Differential Revisions: https://reviews.llvm.org/D53629
llvm-svn: 348788
As Roman Tereshin pointed out in https://reviews.llvm.org/D45541, the
-global-isel option is redundant when -run-pass is given. -global-isel sets up
the GlobalISel passes in the pass manager but -run-pass skips that entirely and
configures it's own pipeline.
llvm-svn: 331603
Dominik Montada