This enabled the use of DomConditionCache. As such, remove the
explicit isImpliedByDomCondition() call. This is probably not
entirely NFC because these APIs don't support exactly the same
cases.
For all of the following reductions:
vector.reduce.or
vector.reduce.and
vector.reduce.xor
vector.reduce.add
vector.reduce.mul
vector.reduce.umin
vector.reduce.umax
vector.reduce.smin
vector.reduce.smax
vector.reduce.fmin
vector.reduce.fmax
if the input operand is the result of a vector.reverse then we can
perform a reduction on the vector.reverse input instead since the answer
is the same. If the reassociation is permitted we can also do the same
folds for these:
vector.reduce.fadd
vector.reduce.fmul
Use ICmpInst::compare() where possible, ConstantFoldCompareInstOperands
in other places. This only changes places where the either the fold is
guaranteed to succeed, or the code doesn't use the resulting compare if
we fail to fold.
This patch is moving out following intrinsics:
* vector.interleave2/deinterleave2
* vector.reverse
* vector.splice
from the experimental namespace.
All these intrinsics exist in LLVM for more than a year now, and are
widely used, so should not be considered as experimental.
Since all optimizations that use range metadata now also handle range attribute, this patch replaces writes of
range metadata for call instructions to range attributes.
This patch folds fabs over select if it is beneficial. I also tried
other interger/fp intrinsics. Only handling fabs shows benefit to some
real-world applications.
In #88217 a large set of matchers was changed to only accept poison
values in splats, but not undef values. This is because we now use
poison for non-demanded vector elements, and allowing undef can cause
correctness issues.
This patch covers the remaining matchers by changing the AllowUndef
parameter of getSplatValue() to AllowPoison instead. We also carry out
corresponding renames in matchers.
As a followup, we may want to change the default for things like m_APInt
to m_APIntAllowPoison (as this is much less risky when only allowing
poison), but this change doesn't do that.
There is one caveat here: We have a single place
(X86FixupVectorConstants) which does require handling of vector splats
with undefs. This is because this works on backend constant pool
entries, which currently still use undef instead of poison for
non-demanded elements (because SDAG as a whole does not have an explicit
poison representation). As it's just the single use, I've open-coded a
getSplatValueAllowUndef() helper there, to discourage use in any other
places.
Prior to #85863, the required parameters of llvm::isKnownNonZero were
Value and DataLayout. After, they are Value, Depth, and SimplifyQuery,
where SimplifyQuery is implicitly constructible from DataLayout. The
change to move Depth before SimplifyQuery needed callers to be updated
unnecessarily, and as commented in #85863, we actually want Depth to be
after SimplifyQuery anyway so that it can be defaulted and the caller
does not need to specify it.
This is the major rename patch that prior patches have built towards.
The DPValue class is being renamed to DbgVariableRecord, which reflects
the updated terminology for the "final" implementation of the RemoveDI
feature. This is a pure string substitution + clang-format patch. The
only manual component of this patch was determining where to perform
these string substitutions: `DPValue` and `DPV` are almost exclusively
used for DbgRecords, *except* for:
- llvm/lib/target, where 'DP' is used to mean double-precision, and so
appears as part of .td files and in variable names. NB: There is a
single existing use of `DPValue` here that refers to debug info, which
I've manually updated.
- llvm/tools/gold, where 'LDPV' is used as a prefix for symbol
visibility enums.
Outside of these places, I've applied several basic string
substitutions, with the intent that they only affect DbgRecord-related
identifiers; I've checked them as I went through to verify this, with
reasonable confidence that there are no unintended changes that slipped
through the cracks. The substitutions applied are all case-sensitive,
and are applied in the order shown:
```
DPValue -> DbgVariableRecord
DPVal -> DbgVarRec
DPV -> DVR
```
Following the previous rename patches, it should be the case that there
are no instances of any of these strings that are meant to refer to the
general case of DbgRecords, or anything other than the DPValue class.
The idea behind this patch is therefore that pure string substitution is
correct in all cases as long as these assumptions hold.
As part of the RemoveDIs project we need LLVM to insert instructions using
iterators wherever possible, so that the iterators can carry a bit of
debug-info. This commit implements some of that by updating the contents of
llvm/lib/Transforms/Utils to always use iterator-versions of instruction
constructors.
There are two general flavours of update:
* Almost all call-sites just call getIterator on an instruction
* Several make use of an existing iterator (scenarios where the code is
actually significant for debug-info)
The underlying logic is that any call to getFirstInsertionPt or similar
APIs that identify the start of a block need to have that iterator passed
directly to the insertion function, without being converted to a bare
Instruction pointer along the way.
Noteworthy changes:
* FindInsertedValue now takes an optional iterator rather than an
instruction pointer, as we need to always insert with iterators,
* I've added a few iterator-taking versions of some value-tracking and
DomTree methods -- they just unwrap the iterator. These are purely
convenience methods to avoid extra syntax in some passes.
* A few calls to getNextNode become std::next instead (to keep in the
theme of using iterators for positions),
* SeparateConstOffsetFromGEP has it's insertion-position field changed.
Noteworthy because it's not a purely localised spelling change.
All this should be NFC.
762f762504/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp (L394-L407)
Comment from @topperc:
> This transforms assumes the mask is a non-zero splat. We only know its
a splat and not provably all 0s. The mask is a constexpr that includes
the address of the global variable. We can't resolve the constant
expression to an exact value.
Fixes#83947.
The strictfp attribute has the requirement that "LLVM will not introduce
any new floating-point instructions that may trap". The llvm.is.fpclass
intrinsic is documented as "The function never raises floating-point
exceptions", and the fcmp instruction may raise one, so we can't
transform the former into the latter in functions with the strictfp
attribute.
This patch refactors the interface of the `computeKnownFPClass` family
to pass `SimplifyQuery` directly.
The motivation of this patch is to compute known fpclass with
`DomConditionCache`, which was introduced by
https://github.com/llvm/llvm-project/pull/73662. With
`DomConditionCache`, we can do more optimization with context-sensitive
information.
Example (extracted from
[fmt/format.h](e17bc67547/include/fmt/format.h (L3555-L3566))):
```
define float @test(float %x, i1 %cond) {
%i32 = bitcast float %x to i32
%cmp = icmp slt i32 %i32, 0
br i1 %cmp, label %if.then1, label %if.else
if.then1:
%fneg = fneg float %x
br label %if.end
if.else:
br i1 %cond, label %if.then2, label %if.end
if.then2:
br label %if.end
if.end:
%value = phi float [ %fneg, %if.then1 ], [ %x, %if.then2 ], [ %x, %if.else ]
%ret = call float @llvm.fabs.f32(float %value)
ret float %ret
}
```
We can prove the signbit of `%value` is always zero. Then the fabs can
be eliminated.
This patch merges the logic of `cannotBeOrderedLessThanZeroImpl` into
`computeKnownFPClass` to improve the signbit inference.
---------
Co-authored-by: Matt Arsenault <arsenm2@gmail.com>
This patch trivially updates various opt passes to handle DPVAssigns. In
all cases, this means some combination of generifying existing code to
handle DPValues and DbgAssignIntrinsics, iterating over DPValues where
previously we did not, or duplicating code for DbgAssignIntrinsics to
the equivalent DPValue function (in inlining and salvageDebugInfo).
This was found in julia when we changed some operations from explicit
loads + stores to memcpys. While applying it to both the src and the
dest seems weird, thats what we do for normal TBAA.
This patch cleans up the duplicate code for folding commutative binops
over `select/phi/minmax`.
Related commits:
+ select support:
88cc35b27e
+ phi support:
8674a023bc
+ minmax support:
624973806c
Fix this issue https://github.com/llvm/llvm-project/issues/72843 .
For naked function, assembly might be using an argument, or otherwise
rely on the frame layout, so don't transformConstExprCastCall
In line with updated shufflevector semantics, this represents the
poison elements rather than undef elements now. This commit is a
pure rename, without any logic changes.
Part of the "RemoveDIs" project to remove debug intrinsics requires
passing block-positions around in iterators rather than as instruction
pointers, allowing some debug-info to reside in BasicBlock::iterator.
This means getInsertionPointAfterDef has to return an iterator, and as
it can return no-instruction that means returning an optional iterator.
This patch changes the signature for getInsertionPtAfterDef and then
patches up the various places that use it to handle the different type.
This would overall be an NFC patch, however in
InstCombinerImpl::freezeOtherUses I've started skipping any debug
intrinsics at the returned insert-position. This should not have any
_meaningful_ effect on the compiler output: at worst it means variable
assignments that are skipped will now cover the freeze instruction and
anything inserted before it, which should be inconsequential.
Sadly: this makes the function signature ugly. This is probably the
ugliest piece of fallout for the "RemoveDIs" work, but it serves the
overall purpose of improving compile times and not allowing `-g` to
affect compiler output, so should be worthwhile in the end.
This is nearly an NFC, the only change is potentially to order that
values are created/names.
Otherwise it is a slight speed boost/simplification to avoid having to
go through the `getFreelyInverted` recursive logic twice to simplify
the extra `not` op.
If we have assosiated attributes i.e `([ret_attrs] (ptrmask (ptrmask
p0, m0), m1))` we should preserve `[ret_attrs]` when combining the two
`llvm.ptrmask`s.
Differential Revision: https://reviews.llvm.org/D156638
We can deduce the former based on the mask / incoming pointer
alignment. We can set the latter based if know the result in non-zero
(this is essentially just caching our analysis result).
Differential Revision: https://reviews.llvm.org/D156636
