Summary:
Currently the attributor needs to give up if a function has external linkage.
This means that the optimization introduced in D97818 will only apply to static
functions. This change uses the Attributor to internalize OpenMP device
routines by making a copy of each function with private linkage and replacing
the uses in the module with it. This allows for the optimization to be applied
to any regular function.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D102824
Summary:
The changes introduced in D97680 create a simpler interface to code that needs
to be globalized. This interface is used to simplify the globalization calls in
the middle end. We can check any globalization call that is only called by a
single thread in the team and replace it with a static shared memory buffer.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D97818
This adds support for addrspace casts involving opaque pointers to
InstCombine, as well as the isEliminableCastPair() helper
(otherwise the assertion failure would just move there).
Add PointerType::hasSameElementTypeAs() to hide the element type
details.
Differential Revision: https://reviews.llvm.org/D104668
There was a bug from cost calculation for partially invariant unswitch.
The costs of non-duplicated blocks are substracted from the total LoopCost, so
anything that is duplicated should not be counted.
Differential Revision: https://reviews.llvm.org/D103816
Summary:
Memory globalization is required to maintain OpenMP standard semantics for data sharing between
worker and master threads. The GPU cannot share data between its threads so must allocate global or
shared memory to store the data in. Currently this is implemented fully in the frontend using the
`__kmpc_data_sharing_push_stack` and __kmpc_data_sharing_pop_stack` functions to emulate standard
CPU stack sharing. The front-end scans the target region for variables that escape the region and
must be shared between the threads. Each variable then has a field created for it in a global record
type.
This patch replaces this functinality with a single allocation command, effectively mimicing an
alloca instruction for the variables that must be shared between the threads. This will be much
slower than the current solution, but makes it much easier to optimize as we can analyze each
variable independently and determine if it is not captured. In the future, we can replace these
calls with an `alloca` and small allocations can be pushed to shared memory.
Reviewed By: tianshilei1992
Differential Revision: https://reviews.llvm.org/D97680
Don't do this while stipping pointer casts, instead fetch it at
the end. This improves compatibility with opaque pointers for the
case where the base object is not opaque.
Currently we drop wrapping flags for expressions like (A + C1)<flags> - C2.
But we can retain flags under certain conditions:
* Adding a smaller constant is NUW if the original AddExpr was NUW.
* Adding a constant with the same sign and small magnitude is NSW, if the
original AddExpr was NSW.
This can improve results after using `SimplifyICmpOperands`, which may
subtract one in order to use stricter predicates, as is the case for
`isKnownPredicate`.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D104319
Patch was reverted due to a bug that existed before it and was exposed
by it. Returning after the underlying bug has been fixed.
Differential Revision: https://reviews.llvm.org/D103959
A backedge-taken count doesn't refer to memory; returning a pointer type
is nonsense. So make sure we always return an integer.
The obvious way to do this would be to just convert the operands of the
icmp to integers, but that doesn't quite work out at the moment:
isLoopEntryGuardedByCond currently gets confused by ptrtoint operations.
So we perform the ptrtoint conversion late for lt/gt operations.
The test changes are mostly innocuous. The most interesting changes are
more complex SCEV expressions of the form "(-1 * (ptrtoint i8* %ptr to
i64)) + %ptr)". This is expected: we can't fold this to zero because we
need to preserve the pointer base.
The call to isLoopEntryGuardedByCond in howFarToZero is less precise
because of ptrtoint operations; this shows up in the function
pr46786_c26_char in ptrtoint.ll. Fixing it here would require more
complex refactoring. It should eventually be fixed by future
improvements to isImpliedCond.
See https://bugs.llvm.org/show_bug.cgi?id=46786 for context.
Differential Revision: https://reviews.llvm.org/D103656
Reapplied without changes -- this was reverted together with an
underlying patch.
-----
Bitcasts having opaque pointer source or result type cannot be
converted into a zero-index GEP, GEP source and result types
always have the same opaque-ness.
Relative to the original patch, an InstCombine test has been
added to show a previously missed pattern, and the Coroutine
test that resulted in the revert has been regenerated.
-----
Move this into a separate function, to make sure that early
returns do not accidentally skip other transforms. This previously
happened for the isSized() check, which skipped folds like
distributing a bitcast over a select.
Perform better analysis when trying to vectorize PHIs.
1. Do not try to vectorize vector PHIs.
2. Do deeper analysis for more profitable nodes for the vectorization.
Before we just tried to vectorize the PHIs of the same type. Patch
improves this and tries to vectorize PHIs with incoming values which
come from the same basic block, have the same and/or alternative
opcodes.
It allows to save the compile time and provides better vectorization
results in general.
Part of D57059.
Differential Revision: https://reviews.llvm.org/D103638
Bitcasts having opaque pointer source or result type cannot be
converted into a zero-index GEP, GEP source and result types
always have the same opaque-ness.
They are not conducive to being stored in git. Instead, we autogenerate
mock model artifacts for use in tests. Production models can be
specified with the cmake flag LLVM_INLINER_MODEL_PATH.
LLVM_INLINER_MODEL_PATH has two sentinel values:
- download, which will download the most recent compatible model.
- autogenerate, which will autogenerate a "fake" model for testing the
model uptake infrastructure.
Differential Revision: https://reviews.llvm.org/D104251
This reverts commit bb1dc876eb.
This patch causes an assertion failure when building an arm64 defconfig
Linux kernel.
See https://reviews.llvm.org/D103959 for a link to the original bug
report and a reduced reproducer.
Use poison instead of undef for cases dealing with unreachable
code. This still leaves the more interesting case of "load from
uninitialized memory" as undef.
getSpecializationCost was returning INT_MAX for a case when specialisation
shouldn't happen, but this wasn't properly checked if specialisation was
forced.
Differential Revision: https://reviews.llvm.org/D104461
This patch lifts the requirement to have the only incoming live block
for Phis. There can be multiple live blocks if the same value comes to
phi from all of them.
Differential Revision: https://reviews.llvm.org/D103959
Reviewed By: nikic, lebedev.ri
This patch updates InstCombine to use poison constant to represent the resulting value of (either semantically or syntactically) unreachable instrs, or a don't-care value of an unreachable store instruction.
This allows more aggressive folding of unused results, as shown in llvm/test/Transforms/InstCombine/getelementptr.ll .
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D104602
This is a more general alternative/extension to D102635. Rather than
handling the special case of "header exit with non-exiting latch",
this unrolls against the smallest exact trip count from any exit.
The latch exit is no longer treated as priviledged when it comes to
full unrolling.
The motivating case is in full-unroll-one-unpredictable-exit.ll.
Here the header exit is an IV-based exit, while the latch exit is
a data comparison. This kind of loop does not get rotated, because
the latch is already exiting, and loop rotation doesn't try to
distinguish IV-based/analyzable latches.
Differential Revision: https://reviews.llvm.org/D102982
DSE will currently only remove stores in the same block unless they can
be guaranteed to be loop invariant. This expands that to any stores that
are in the same Loop, at the same loop level. This should still account
for where AA/MSSA will not handle aliasing between loops, but allow the
dead stores to be removed where they overlap in the same loop iteration.
It requires adding loop info to DSE, but that looks fairly harmless.
The test case this helps is from code like this, which can come up in
certain matrix operations:
for(i=..)
dst[i] = 0;
for(j=..)
dst[i] += src[i*n+j];
After LICM, this becomes:
for(i=..)
dst[i] = 0;
sum = 0;
for(j=..)
sum += src[i*n+j];
dst[i] = sum;
The first store is dead, and with this patch is now removed.
Differntial Revision: https://reviews.llvm.org/D100464
This problem is exposed by D104598, after it tail-merges `ret` in
`@test_inline_constraint_S_label`, the verifier would start complaining
`invalid operand for inline asm constraint 'S'`.
Essentially, taking address of a block is mismodelled in IR.
It should probably be an explicit instruction, a first one in block,
that isn't identical to any other instruction of the same type,
so that it can't be hoisted.
This patch adds an optional PriorityInlineOrder, which uses the heap to order inlining.
The callsite which size is smaller would have a higher priority.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D104028
On ELF, the D1003372 optimization can apply to more cases. There are two
prerequisites for making `__profd_` private:
* `__profc_` keeps `__profd_` live under compiler/linker GC
* `__profd_` is not referenced by code
The first is satisfied because all counters/data are in a section group (either
`comdat any` or `comdat noduplicates`). The second requires that the function
does not use value profiling.
Regarding the second point: `__profd_` may be referenced by other text sections
due to inlining. There will be a linker error if a prevailing text section
references the non-prevailing local symbol.
With this change, a stage 2 (`-DLLVM_TARGETS_TO_BUILD=X86 -DLLVM_BUILD_INSTRUMENTED=IR`)
clang is 4.2% smaller (1-169620032/177066968).
`stat -c %s **/*.o | awk '{s+=$1}END{print s}' is 2.5% smaller.
Reviewed By: davidxl, rnk
Differential Revision: https://reviews.llvm.org/D103717
Sami Tolvanen