Summary:
The module slice describes which functions we can analyze and transform
while working on an SCC as part of the Attributor-CGSCC pass. So far we
simply restricted it to the SCC.
Reviewers: jdoerfert
Differential Revision: https://reviews.llvm.org/D86319
Even if noundef is deduced for a position, we should not manifest it when the position is dead.
This is because the associated values with dead positions are replaced with undef values by AAIsDead.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D86565
This patch introduces a new abstract attribute `AANoUndef` which corresponds to `noundef` IR attribute and deduce them.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D85184
All these tests already explicitly test against both legacy PM and NPM.
$ sed -i 's/ -attributor / -attributor -enable-new-pm=0 /g' $(rg --path-separator // -l -- -passes=)
$ sed -i 's/ -attributor-cgscc / -attributor-cgscc -enable-new-pm=0 /g' $(rg --path-separator // -l -- -passes=)
Now all tests in Transforms/Attributor/ pass under NPM.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D84813
Summary:
All tests are updated, except wrapper.ll since it is not working nicely
with newly created functions.
Reviewers: jdoerfert, uenoku, baziotis, homerdin
Subscribers: arphaman, jfb, kuter, bbn, okura, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D84130
Attributor tests are mostly updated using the auto upgrade scripts but
sometimes we forget. If we do it manually or continue using old check
lines that still match we see unrelated changes down the line. This is
just a cleanup.
Summary:
This patch changes call graph analysis to recognize callback call sites
and add an artificial 'reference' call record from the broker function
caller to the callback function in the call graph. A presence of such
reference enforces bottom-up traversal order for callback functions in
CG SCC pass manager because callback function logically becomes a callee
of the broker function caller.
Reviewers: jdoerfert, hfinkel, sstefan1, baziotis
Reviewed By: jdoerfert
Subscribers: hiraditya, kuter, sstefan1, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D82572
We should never give up on AAIsDead as it guards other AAs from
unreachable code (in which SSA properties are meaningless). We did
however use required dependences on some queries in AAIsDead which
caused us to invalidate AAIsDead if the queried AA got invalidated.
We now use optional dependences instead. The bug that exposed this is
added to the liveness.ll test and other test changes show the impact.
Bug report by @sdmitriev.
During an update of AAIsDead, new instructions become live. If we query
information from them, the result is often just the initial state, e.g.,
for call site `noreturn` and `nounwind`. We will now trigger an update
for cached attributes during the AAIsDead update, though other AAs might
later use the same API.
We now use getPointerDereferenceableBytes to determine `nonnull` and
`dereferenceable` facts from the IR. We also use getPointerAlignment in
AAAlign for the same reason. The latter can interfere with callbacks so
we do restrict it to non-function-pointers for now.
In a recent patch we introduced a problem with abstract attributes that
were assumed dead at some point. Since `Attributor::updateAA` was
introduced in 95e0d28b71, we did not
remember the dependence on the liveness AA when an abstract attribute
was assumed dead and therefore not updated.
Explicit reproducer added in liveness.ll.
---
Single run of the Attributor module and then CGSCC pass (oldPM)
for SPASS/clause.c (~10k LLVM-IR loc):
Before:
```
calls to allocation functions: 509242 (345483/s)
temporary memory allocations: 98666 (66937/s)
peak heap memory consumption: 18.60MB
peak RSS (including heaptrack overhead): 103.29MB
total memory leaked: 269.10KB
```
After:
```
calls to allocation functions: 529332 (355494/s)
temporary memory allocations: 102107 (68574/s)
peak heap memory consumption: 19.40MB
peak RSS (including heaptrack overhead): 102.79MB
total memory leaked: 269.10KB
```
Difference:
```
calls to allocation functions: 20090 (1339333/s)
temporary memory allocations: 3441 (229400/s)
peak heap memory consumption: 801.45KB
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B
```
When the Attributor was created the test update scripts were not well
suited to deal with the challenges of IR attribute checking. This
partially improved.
Since then we also added three additional configurations that need
testing; in total we now have the following four:
{ TUNIT, CGSCC } x { old pass manager (OPM), new pass manager (NPM) }
Finally, the number of developers and tests grew rapidly (partially due
to the addition of ArgumentPromotion and IPConstantProp tests), which
resulted in tests only being run in some configurations, different
prefixes being used, and different "styles" of checks being used.
Due to the above reasons I believed we needed to take another look at
the test update scripts. While we started to use them, via UTC_ARGS:
--enable/disable, the other problems remained. To improve the testing
situation for *all* configurations, to simplify future updates to the
test, and to help identify subtle effects of future changes, we now use
the test update scripts for (almost) all Attributor tests.
An exhaustive prefix list minimizes the number of check lines and makes
it easy to identify and compare configurations.
Tests have been adjusted in the process but we tried to keep their
intend unchanged.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D76588
When the Attributor was created the test update scripts were not well
suited to deal with the challenges of IR attribute checking. This
partially improved.
Since then we also added three additional configurations that need
testing; in total we now have the following four:
{ TUNIT, CGSCC } x { old pass manager (OPM), new pass manager (NPM) }
Finally, the number of developers and tests grew rapidly (partially due
to the addition of ArgumentPromotion and IPConstantProp tests), which
resulted in tests only being run in some configurations, different
prefixes being used, and different "styles" of checks being used.
Due to the above reasons I believed we needed to take another look at
the test update scripts. While we started to use them, via UTC_ARGS:
--enable/disable, the other problems remained. To improve the testing
situation for *all* configurations, to simplify future updates to the
test, and to help identify subtle effects of future changes, we now use
the test update scripts for (almost) all Attributor tests.
An exhaustive prefix list minimizes the number of check lines and makes
it easy to identify and compare configurations.
Tests have been adjusted in the process but we tried to keep their
intend unchanged.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D76588
We are often interested in an assumed constant and sometimes it has to
be an integer constant. Before we only looked for the latter, now we can
ask for either.
In addition to the module pass, this patch introduces a CGSCC pass that
runs the Attributor on a strongly connected component of the call graph
(both old and new PM). The Attributor was always design to be used on a
subset of functions which makes this patch mostly mechanical.
The one change is that we give up `norecurse` deduction in the module
pass in favor of doing it during the CGSCC pass. This makes the
interfaces simpler but can be revisited if needed.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D70767
This patch modularizes the way we check for no-alias call site arguments
by putting the existing logic into helper functions. The reasoning was
not changed but special cases for readonly/readnone were added.
Summary:
New `@test13` in `Attributor/align.ll` is the main motivation - `null` pointer
really does not limit our alignment knowledge, in fact it is fully aligned
since it has no bits set.
Here we don't special-case `null` pointer because it is somewhat controversial
to add one more place where we enforce that `null` pointer is zero,
but instead we do the more general thing of trying to perform constant-fold
of pointer constant to an integer, and perform alignment inferrment on that.
Reviewers: jdoerfert, gchatelet, courbet, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, arphaman, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73131
This is the second step after D67871 to make use of abstract call sites.
In this patch the argument we associate with a abstract call site
argument can be the one in the callback callee instead of the one in the
callback broker.
Caveat: We cannot allow no-alias arguments for problematic callbacks:
As described in [1], adding no-alias (or restrict) to arguments could
break synchronization as the synchronization effect, e.g., a barrier,
does not "alias" with the pointer anymore. This disables no-alias
annotation for potentially problematic arguments until we implement the
fix described in [1].
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D68008
[1] Compiler Optimizations for OpenMP, J. Doerfert and H. Finkel,
International Workshop on OpenMP 2018,
http://compilers.cs.uni-saarland.de/people/doerfert/par_opt18.pdf
The Attributor can, to some degree, do what IPConstantProp does. We can
consequently use the corner cases already collected and tested for in
the IPConstantProp tests to improve Attributor test coverage.
This exposed various bugs fixed in previous Attributor patches.
Not all functionality of IPConstantProp is available in AAValueSimplify
and AAIsDead so some tests show that we cannot perform the expected
constant propagation.
Reviewers: fhahn, efriedma, mssimpso, davide
Subscribers: bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69748
sstefan1