This treats the zext nneg as sext if X is known to have sufficient sign
bits to allow the zext or truncate or both to removed. This code is
taken from the same optimization for sext.
BlockFrequencyInfo calculates block frequencies as Scaled64 numbers but as a last step converts them to unsigned 64bit integers (`BlockFrequency`). This improves the factors picked for this conversion so that:
* Avoid big numbers close to UINT64_MAX to avoid users overflowing/saturating when adding multiply frequencies together or when multiplying with integers. This leaves the topmost 10 bits unused to allow for some room.
* Spread the difference between hottest/coldest block as much as possible to increase precision.
* If the hot/cold spread cannot be represented loose precision at the lower end, but keep the frequencies at the upper end for hot blocks differentiable.
PR #66334 tried to renumber slot indexes before register allocation, but
the numbering was still affected by list entries for instructions which
had been erased. Fix this to make the register allocator's live range
length heuristics even less dependent on the history of how instructions
have been added to and removed from SlotIndexes's maps.
The current implementation tries to handle the high and low halves
separately, but that's less efficient in most cases; use a wide SETCC
instead.
Differential Revision: https://reviews.llvm.org/D151358
We can compute a simpler expression for Lo for these cases. This
is an alternative for the test cases in D151180 that works for
more targets.
This is similar to some of the special cases we have for expanding
setcc operands.
Differential Revision: https://reviews.llvm.org/D151182
Correct the legality of i32 mul_lohi on AArch64.
Previously, AArch64 incorrectly reported i32 mul_lohi as Legal.
This allowed BuildUDIV/SDIV to use them. A later DAGCombiner would
replace them with MULHS/MULHU because only the high half was used.
This conversion does not check the legality of MULHS/MULHU under
the assumption that LegalizeDAG can turn it back into MUL_LOHI later.
After they are converted to MULHS/MULHU, DAGCombine ran and saw that
these operations aren't supported but an i64 MUL is. So they get
converted to that plus a shift. Without this, LegalizeDAG would
convert back MUL_LOHI and isel would fail to find a pattern.
This patch teaches BuildUDIV/SDIV to create the wide mul and shift
so that we can report the correct operation legality on AArch64. It
also enables div by constant folding for more cases on VE.
I don't know if VE wants this div by constant optimization or not. If they
don't want it, they can use the isIntDivCheap hook to disable it.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D150333
Alignment of an alloca in IR can be lower than the preferred alignment
on purpose, but this override essentially treats the preferred
alignment as the minimum alignment.
The patch changes this behavior to always use the specified
alignment. If alignment is not set explicitly in LLVM IR, it is set to
DL.getPrefTypeAlign(Ty) in computeAllocaDefaultAlign.
Tests are changed as well: explicit alignment is increased to match
the preferred alignment if it changes output, or omitted when it is
hard to determine the right value (e.g. for pointers, some structs, or
weird types).
Differential Revision: https://reviews.llvm.org/D135462
These are essentially add/sub 1 with a clamping value.
AMDGPU has instructions for these. CUDA/HIP expose these as
atomicInc/atomicDec. Currently we use target intrinsics for these,
but those do no carry the ordering and syncscope. Add these to
atomicrmw so we can carry these and benefit from the regular
legalization processes.
There is a minor codegen regression here (an extra and instruction).
The reason is that CGP only eliminates fallthrough branches if it
has made some other kind of change, and with opaque pointers that
other change does not occur.
Ideally, we should probably always try to eliminate fallthroughs,
but this runs into the problem that performing a dummy fallthrough
is a common pattern in tests for forcing SDAG to select them
separately, so it's not quite that simple.
Alignment of an alloca in IR can be lower than the preferred alignment
on purpose, but this override essentially treats the preferred
alignment as the minimum alignment.
The patch changes this behavior to always use the specified
alignment. If alignment is not set explicitly in LLVM IR, it is set to
DL.getPrefTypeAlign(Ty) in computeAllocaDefaultAlign.
Tests are changed as well: explicit alignment is increased to match
the preferred alignment if it changes output, or omitted when it is
hard to determine the right value (e.g. for pointers, some structs, or
weird types).
Differential Revision: https://reviews.llvm.org/D135462
Change to use VEISD::CMPI/CMPU/CMPF/CMPQ and VEISD::CMOV in combineSelectCC
for better optimization. Support VEISD::CMPI/CMPU in combineTRUNCATE also
to optimize truncate. Remove obsolete lower patterns from VEInstrInfo.td.
Update regression tests also.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D136049
Change to use VEISD::CMOV in combineSelect for better optimization.
Support VEISD::CMOV in combineTRUNCATE also to optimize trancate.
Merge functions to handle condition codes to VE.h. And add basic
CMOV patterns to VEInstrInfo.td. Update regression tests also.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D135878
This removes the ptrtoint from the load's pointer operand, although we
can't entirely eliminate these to get the LSB shift. In a future
patch, this will avoid ptrtoint in the case where the atomic is
overaligned to the word size.
Disable FMAX/FMIN selection from select_cc in VEInstrInfo.td because of
the lack of NaN consideration. This patch removes such selection from
VEInstrInfo.td and lets llvm work on it in combineMinNumMaxNum.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D134595
Support smax/smin in VEInstrInfo.td. Remove obsolete patterns for
smax/smin. Add regression tests for smax/smin/umax/umin.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D134583
Add maxnum and minnum for float and double. Lowering is already
implemented, so this patch changes them legal and adds regression
tests.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D134108
VE has fused multiply-add instruction for only vector calculations. This
patch forces to expand scalar FMA to multiply and add instructions.
This patch also adds regression test.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D134107
For remainder:
If (1 << (Bitwidth / 2)) % Divisor == 1, we can add the high and low halves
together and use a (Bitwidth / 2) urem. If (BitWidth /2) is a legal integer
type, this urem will be expand by DAGCombiner using multiply by magic
constant. We do have to take into account that adding high and low
together can produce a carry, making it a (BitWidth / 2)+1 bit number.
So we need to also add back in the carry from the first addition.
For division:
We can use the above trick to compute the remainder, subtract that
remainder from the dividend, then multiply by the multiplicative
inverse of the Divisor modulo (1 << BitWidth).
This is based on the section "Remainder by Summing Digits" in
Hacker's delight.
The remainder trick is similar to a trick you may have learned for
determining if a decimal number is divisible by 3. You can add all the
digits together and see if the sum is divisible by 3. If you're not sure
if the sum is divisible by 3, you can add its digits together. This
can be repeated until you have a single decimal digit. If that digit
is 3, 6, or 9, then the original number is divisible by 3. This works
because 10 % 3 == 1.
gcc already does this same trick. There are additional tricks gcc
does urem as well as srem, udiv, and sdiv that I plan to add in
future patches.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D130862
While working on https://reviews.llvm.org/D131429, I got a test diff in
one of the VE tests and running update_llc_test_checks.py deleted all the
code for that function. This updates the regex to handle this new output.
Reviewed By: kaz7
Differential Revision: https://reviews.llvm.org/D131431
Restructure the current implementation of eliminateFrameIndex function
in order to support more instructions.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D129034
Restructure the current implementation of eliminateFrameIndex function
in order to support more instructions.
Reviewed By: efocht
Differential Revision: https://reviews.llvm.org/D129034
We do not have general reassociation here (and probably
do not need it), but I noticed these were missing in
patches/tests motivated by D111530, so we can at
least handle the simplest patterns.
The VE test diff looks correct, but we miss that
pattern in IR currently:
https://alive2.llvm.org/ce/z/u66_PM
Make match patterns more permissive to be invariant to register
allocation choices.
Reviewed By: kaz7
Differential Revision: https://reviews.llvm.org/D111312
We were trying to expand these if they were going to be expanded
in op legalization so that we generated the minimum number of
operations. We failed to take into account that NVT could be
promoted to another legal type in op legalization.
Hoping this fixes the issue on the VE target reported as a follow
up to D96681. The check line changes were taken from before
1e46b6f4012399a2fef5fbbb4ed06fc919835414 so this patch does
appear to improve some cases that had previously regressed.
Support EH_SJLJ_LONGJMP, EH_SJLJ_SETJMP, and EH_SJLJ_SETUP_DISPATCH
for SjLj exception handling. NC++ uses SjLj exception handling, so
implement it first. Add regression tests also.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D94071
In order to support SJLJ exception, implement llvm.eh.sjlj.lsda first.
Add regression test also.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D93811
Change default CPU name of SX-Aurora VE from "ve" to "generic" similar
to other architectures.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D93836
Change to optimize references of elements of aggregate data. Also
add regression tests.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D93627
Support atomic exchange and atomic compare and exchange instructions.
Change CAS and TS1AM instructions for ISel patterns. Add selectADDRzi
pattern for them. Add TS1AM pseudo instruction also for better ISel.
Add shouldExpandAtomicRMWInIR() function to expand all atomicrmw
instructions except atomicrmw xchg. Add custom lower for i8/i16
atomicrmw xchg. Modify replaceFI to support CAS/TS1AM instructions
which use "reg+disp" operands instead of "reg+imm+disp" operands.
And, add several regression tests to check the correctness.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D93161
Optimize prologue/epilogue instructions if a given function use GOT but
do not call other functions by eliminating FP. Previously, we had wrong
implementations taken from other architectures. Update regression tests
also.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D92313
Previously, these check routines accepted non-generatble instructions.
This time, I clean them and add assert for those non-generatable
instructions.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D92254
Optimize eliminate FP mechanism. This time optimize a function which has
no call but fixed stack objects. LLVM eliminates FP on such functions now.
Also, optimize GOT/PLT registers save/restore instructions if a given
function doesn't uses them. In addition, remove generating mechanism of
`.cfi` instructions since those are taken from other architectures and not
inspected yet. Update regression tests, also.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D92251
Change the way to truncate i64 to i32 in I64 registers. VE assumed
sext values previously. Change it to zext values this time to make
it match to the LLVM behaviour.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D92226
