Commit Graph

17 Commits

Author SHA1 Message Date
Matt Arsenault 28f2f66200 GlobalISel: Use LLT in memory legality queries
This enables proper lowering of non-byte sized loads. We still aren't
faithfully preserving memory types everywhere, so the legality checks
still only consider the size.
2021-06-30 17:44:13 -04:00
Matt Arsenault 89baeaef2f Reapply "RegAllocFast: Rewrite and improve"
This reverts commit 73a6a164b8.
2020-09-30 10:35:25 -04:00
Muhammad Omair Javaid 73a6a164b8 Revert "Reapply Revert "RegAllocFast: Rewrite and improve""
This reverts commit 55f9f87da2.

Breaks following buildbots:
http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4306
http://lab.llvm.org:8011/builders/lldb-aarch64-ubuntu/builds/9154
2020-09-22 14:40:06 +05:00
Matt Arsenault 55f9f87da2 Reapply Revert "RegAllocFast: Rewrite and improve"
This reverts commit dbd53a1f0c.

Needed lldb test updates
2020-09-21 15:45:27 -04:00
Eric Christopher dbd53a1f0c Temporarily Revert "RegAllocFast: Rewrite and improve"
as it's breaking a few tests in the lldb test suite.

Bot: http://lab.llvm.org:8011/builders/lldb-arm-ubuntu/builds/4226/steps/test/logs/stdio

This reverts commit c8757ff3aa.
2020-09-18 18:11:21 -07:00
Matt Arsenault c8757ff3aa RegAllocFast: Rewrite and improve
This rewrites big parts of the fast register allocator. The basic
strategy of doing block-local allocation hasn't changed but I tweaked
several details:

Track register state on register units instead of physical
registers. This simplifies and speeds up handling of register aliases.
Process basic blocks in reverse order: Definitions are known to end
register livetimes when walking backwards (contrary when walking
forward then uses may or may not be a kill so we need heuristics).

Check register mask operands (calls) instead of conservatively
assuming everything is clobbered.  Enhance heuristics to detect
killing uses: In case of a small number of defs/uses check if they are
all in the same basic block and if so the last one is a killing use.
Enhance heuristic for copy-coalescing through hinting: We check the
first k defs of a register for COPYs rather than relying on there just
being a single definition.  When testing this on the full llvm
test-suite including SPEC externals I measured:

average 5.1% reduction in code size for X86, 4.9% reduction in code on
aarch64. (ranging between 0% and 20% depending on the test) 0.5%
faster compiletime (some analysis suggests the pass is slightly slower
than before, but we more than make up for it because later passes are
faster with the reduced instruction count)

Also adds a few testcases that were broken without this patch, in
particular bug 47278.

Patch mostly by Matthias Braun
2020-09-18 14:05:18 -04:00
Petar Avramovic 1f559353a7 [MIPS GlobalISel] Select andi, ori and xori
Introduce IntImmLeaf version of PatLeaf immZExt16 for 32-bit immediates.
Change immZExt16 with imm32ZExt16 for andi, ori and xori.
This keeps same behavior for SDAG and allows for GlobalISel selectImpl
to select 'G_CONSTANT imm' + G_AND, G_OR, G_XOR into ANDi, ORi, XORi,
respectively, when 32-bit imm satisfies imm32ZExt16 predicate: zero
extending 16 low bits of imm is equal to imm.
Large number of test changes comes from zero extending of small types
which is transformed into 'and' with bitmask in legalizer.

Differential Revision:https://reviews.llvm.org/D70185
2019-11-15 11:41:25 +01:00
Petar Avramovic dda8e95540 [MIPS GlobalISel] Select addiu
Introduce IntImmLeaf version of PatLeaf immSExt16 for 32-bit immediates.
Change immSExt16 with imm32SExt16 for addiu.
This keeps same behavior for SDAG and allows for GlobalISel selectImpl
to select 'G_CONSTANT imm' + G_ADD into ADDIu when 32-bit imm satisfies
imm32SExt16 predicate: sign extending 16 low bits of imm is equal to imm.

Differential Revision: https://reviews.llvm.org/D70184
2019-11-15 11:36:13 +01:00
Matt Arsenault fba82858f2 GlobalISel: Don't create G_UADDE with constant false carry in
The x86 tests are now broken (in paticular add-scalar.ll now hits the
DAG fallback) due to not handling G_UADDO. The DAG x86 backend has a
custom lowering for this, so that will need to be implemented.

llvm-svn: 369673
2019-08-22 17:29:17 +00:00
Amara Emerson 946b1246d6 [GlobalISel] Enable CSE in the IRTranslator & legalizer for -O0 with constants only.
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
2019-04-15 05:04:20 +00:00
Matt Arsenault c2e35a6f32 RegAllocFast: Remove early selection loop, the spill calculation will report cost 0 anyway for free regs
The 2nd loop calculates spill costs but reports free registers as cost
0 anyway, so there is little benefit from having a separate early
loop.

Surprisingly this is not NFC, as many register are marked regDisabled
so the first loop often picks up later registers unnecessarily instead
of the first one available in the allocation order...

Patch by Matthias Braun

llvm-svn: 356499
2019-03-19 19:01:34 +00:00
Petar Avramovic 3e0da146ac [MIPS GlobalISel] Improve selection of constants
Certain 32 bit constants can be generated with a single instruction
instead of two. Implement materialize32BitImm function for MIPS32.

Differential Revision: https://reviews.llvm.org/D59369

llvm-svn: 356238
2019-03-15 07:07:50 +00:00
Petar Avramovic bd39569913 [MIPS GlobalISel] Select G_UADDO
Lower G_UADDO.
Legalize G_UADDO for MIPS32

Differential Revision: https://reviews.llvm.org/D58671

llvm-svn: 354900
2019-02-26 17:22:42 +00:00
Petar Avramovic b8276f2280 [MIPS GlobalISel] Lower G_UADDE and narrowScalar G_ADD
Lower G_UADDE and legalize G_ADD using narrowScalar on MIPS32.

Differential Revision: https://reviews.llvm.org/D54580

llvm-svn: 349346
2018-12-17 12:31:07 +00:00
Petar Jovanovic aa97890d66 [MIPS GlobalISel] Legalize i64 add
Custom legalize s64 G_ADD for MIPS32.

Patch by Petar Avramovic.

Differential Revision: https://reviews.llvm.org/D52652

llvm-svn: 344007
2018-10-08 23:59:37 +00:00
Petar Jovanovic 1fa5051bad [MIPS GlobalISel] Legalize i8 and i16 add
Legalize G_ADD for types smaller than i32.
LegalizationArtifactCombiner replaces extend instructions with appropriate
bitwise instructions.

Patch by Petar Avramovic.

Differential Revision: https://reviews.llvm.org/D51213

llvm-svn: 340697
2018-08-26 07:25:33 +00:00
Petar Jovanovic 366857a23a [MIPS GlobalISel] Select add i32, i32
Add the minimal support necessary to lower a function that returns the
sum of two i32 values.
Support argument/return lowering of i32 values through registers only.
Add tablegen for regbankselect and instructionselect.

Patch by Petar Avramovic.

Differential Revision: https://reviews.llvm.org/D44304

llvm-svn: 329819
2018-04-11 15:12:32 +00:00