Moved extractParts() and extractVectorParts() from LegalizerHelper
to Utils to be able to use it in different passes.
extractParts() will also try to use unmerge when doing irregular
splits where possible, falling back to extract elements when not.
vecreduce_add(mul(ext, ext)) -> vecreduce_add(udot)
vecreduce_add(ext) -> vecreduce_add(ext)
Vectors of scalar size of 8-bits with element count of multiples of 8
This will make it easy for callers to see issues with and fix up calls
to createTargetMachine after a future change to the params of
TargetMachine.
This matches other nearby enums.
For downstream users, this should be a fairly straightforward
replacement,
e.g. s/CodeGenOpt::Aggressive/CodeGenOptLevel::Aggressive
or s/CGFT_/CodeGenFileType::
Remove CodeGen leftovers from the old combiner backend and adapt the API to fit the new backend better.
It's now quite a bit closer to how InstructionSelector works.
- `CombinerInfo` is now a simple "options" struct.
- `Combiner` is now the base class of all TableGen'd combiner implementation.
- Many fields have been moved from derived classes into that class.
- It has been refactored to create & own the Observer and Builder.
- `tryCombineAll` TableGen'd method can now be renamed, which allows targets to implement the actual `tryCombineAll` call manually and do whatever they want to do before/after it.
Note: `CombinerHelper` needs to be mutable because none of its methods are const. This can be revisited later.
Depends on D158710
Reviewed By: aemerson, dsanders
Differential Revision: https://reviews.llvm.org/D158713
Only a few minor test changes needed because I removed the "helper" suffix from the combiner name, as it's not really a helper anymore but more like the implementation itself.
Depends on D153757
NOTE: This would land iff D153757 (RFC) lands too.
Reviewed By: aemerson
Differential Revision: https://reviews.llvm.org/D153850
There is no case where those functions return false. It's always return true.
Even if they were to return false, it's not really something we should rely on I think.
With the current combiner implementation, it would just make `tryCombineAll` return false without retrying anymore rules.
I also believe that if an applyer were to return false, it would mean that the match function is not good enough. Asserting on failure in an apply function is a better idea, IMO.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D153619
Before, the isPreLegalize() query in CombinerHelper only checked for the
presence of a LegalizerInfo object. This is problematic when we want to have
a combine actually check for legality in a pre-legalizer combine pass, since
if we pass a LegalizerInfo object to the constructor it causes the combines to
think that we're running *post* legalizer, which isn't true.
This change fixes it to instead check an explicit bool that passes to signal
whether the pass will be run before or after legalization.
Doing so exposed a bug in the extending loads combine, which tried to check for
legality of candidate extending loads if LegalizerInfo was present. Since we
only ran it pre-legalizer and therefore with a null LegalizerInfo, it never
actually ran. Also fixes the legality checks to keep the tests passing.
Differential Revision: https://reviews.llvm.org/D135044
In COFF, the immediates in IMAGE_REL_ARM64_PAGEBASE_REL21 relocations
are limited to 21 bit signed, i.e. the offset has to be less than
(1 << 20). The previous limit did intend to cover for this case, but
had missed that the 21 bit field was signed.
This fixes issue https://github.com/llvm/llvm-project/issues/54753.
Differential Revision: https://reviews.llvm.org/D123160
Try simplify G_UADDO with 8 or 16 bit operands to wide G_ADD and TBNZ if
result is only used in the no-overflow case. It is restricted to cases
where we know that the high-bits of the operands are 0. If there's an
overflow, then the the 9th or 17th bit must be set, which can be checked
using TBNZ.
Reviewed By: paquette
Differential Revision: https://reviews.llvm.org/D111888
Rework getConstantstVRegValWithLookThrough in order to make it clear if we
are matching integer/float constant only or any constant(default).
Add helper functions that get DefVReg and APInt/APFloat from constant instr
getIConstantVRegValWithLookThrough: integer constant, only G_CONSTANT
getFConstantVRegValWithLookThrough: float constant, only G_FCONSTANT
getAnyConstantVRegValWithLookThrough: either G_CONSTANT or G_FCONSTANT
Rename getConstantVRegVal and getConstantVRegSExtVal to getIConstantVRegVal
and getIConstantVRegSExtVal. These now only match G_CONSTANT as described
in comment.
Relevant matchers now return both DefVReg and APInt/APFloat.
Replace existing uses of getConstantstVRegValWithLookThrough and
getConstantVRegVal with new helper functions. Any constant match is
only required in:
ConstantFoldBinOp: for constant argument that was bit-cast of float to int
getAArch64VectorSplat: AArch64::G_DUP operands can be any constant
amdgpu select for G_BUILD_VECTOR_TRUNC: operands can be any constant
In other places use integer only constant match.
Differential Revision: https://reviews.llvm.org/D104409
The combines in `tryCombineMemCpyFamily` have heuristics (e.g.
`TLI.getMaxStoresPerMemset`) which consider size. So, theoretically, enabling
these combines on minsize functions shouldn't be harmful.
With this enabled we save 0.9% geomean on CTMark at -Oz, and 5.1% on Bullet.
There are no code size regressions.
Differential Revision: https://reviews.llvm.org/D102198
We never bothered to have a separate set of combines for -O0 in the prelegalizer
before. This results in some minor performance hits for a mode where performance
isn't a concern (although not regressing code size significantly is still preferable).
This also removes the CSE option since we don't need it for -O0.
Through experiments, I've arrived at a set of combines that gets the most code
size improvement at -O0, while reducing the amount of time spent in the combiner
by around 35% give or take.
Differential Revision: https://reviews.llvm.org/D102038
SelectionDAG has separate ISD opcodes for regular global values and thread-local
global values, while GlobalISel does not.
This combine was ported from SDAG directly without knowing that. As a result,
it was running on TLS globals.
This makes it so that `matchFoldGlobalOffset` doesn't match on TLS globals, and
adds an assert to `selectTLSGlobalValue` to make sure that TLS globals never
have offsets.
Differential Revision: https://reviews.llvm.org/D101478
Darwin platforms for both AArch64 and X86 can provide optimized `bzero()`
routines. In this case, it may be preferable to use `bzero` in place of a
memset of 0.
This adds a G_BZERO generic opcode, similar to G_MEMSET et al. This opcode can
be generated by platforms which may want to use bzero.
To emit the G_BZERO, this adds a pre-legalize combine for AArch64. The
conditions for this are largely a port of the bzero case in
`AArch64SelectionDAGInfo::EmitTargetCodeForMemset`.
The only difference in comparison to the SelectionDAG code is that, when
compiling for minsize, this will fire for all memsets of 0. The original code
notes that it's not beneficial to do this for small memsets; however, using
bzero here will save a mov from wzr. For minsize, I think that it's preferable
to prioritise omitting the mov.
This also fixes a bug in the libcall legalization code which would delete
instructions which could not be legalized. It also adds a check to make sure
that we actually get a libcall name.
Code size improvements (Darwin):
- CTMark -Os: -0.0% geomean (-0.1% on pairlocalalign)
- CTMark -Oz: -0.2% geomean (-0.5% on bullet)
Differential Revision: https://reviews.llvm.org/D99358
This reverts commit 962b73dd0fc3906980e597f72a35eee7121cc5e2.
This commit was reverted because of some internal SPEC test failures.
It turns out that this wasn't actually relevant to anything in open source, so
it's safe to recommit this.
This reverts commit 61b4702a408834228c1c139b0e9af98616774db4.
We were seeing some test failures in SPECINT2006 due to this change. Reverting
to investigate.
This is pretty much just ports `performGlobalAddressCombine` from
AArch64ISelLowering. (AArch64 doesn't use the generic DAG combine for this.)
This adds a pre-legalize combine which looks for this pattern:
```
%g = G_GLOBAL_VALUE @x
%ptr1 = G_PTR_ADD %g, cst1
%ptr2 = G_PTR_ADD %g, cst2
...
%ptrN = G_PTR_ADD %g, cstN
```
And then, if possible, transforms it like so:
```
%g = G_GLOBAL_VALUE @x
%offset_g = G_PTR_ADD %g, -min(cst)
%ptr1 = G_PTR_ADD %offset_g, cst1
%ptr2 = G_PTR_ADD %offset_g, cst2
...
%ptrN = G_PTR_ADD %offset_g, cstN
```
Where min(cst) is the smallest out of the G_PTR_ADD constants.
This means we should save at least one G_PTR_ADD.
This also updates code in the legalizer + selector which assumes that
G_GLOBAL_VALUE will never have an offset and adds/updates relevant tests.
Differential Revision: https://reviews.llvm.org/D96624
We try to do this optimization if we can determine that testing for the
truncated bits with an eq/ne predicate results in the same thing as testing
the lower bits.
Differential Revision: https://reviews.llvm.org/D95645
There are a lot of combines in AArch64PostLegalizerCombiner which exist to
facilitate instruction matching in the selector. (E.g. matching for G_ZIP and
other shuffle vector pseudos)
It still makes sense to select these instructions at -O0.
Matching earlier in a combiner can reduce complexity in the selector
significantly. For example, a good portion of our selection code for compares
would be a lot easier to represent in a combine.
This patch moves matching combines into a "AArch64PostLegalizerLowering"
combiner which runs at all optimization levels.
Also, while we're here, improve the documentation for the
AArch64PostLegalizerCombiner, and fix up the filepath in its file comment.
And also add a 'r' which somehow got dropped from a bunch of function names.
https://reviews.llvm.org/D89820
AArch64, X86 and Mips currently directly consumes these and custom
lowering to produce a libcall, but really these should follow the
normal legalization process through the libcall/lower action.
Summary:
Adds the ability to add members to a generated combiner via
a State base class. In the current AArch64PreLegalizerCombiner
this is used to make Helper available without having to
provide it to every call.
As part of this, split the command line processing into a
separate object so that it still only runs once even though
the generated combiner is constructed more frequently.
Depends on D81862
Reviewers: aditya_nandakumar, bogner, volkan, aemerson, paquette, arsenm
Reviewed By: arsenm
Subscribers: jvesely, wdng, nhaehnle, kristof.beyls, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D81863