9 Commits

Author SHA1 Message Date
Johannes Doerfert
b51b83f68e [Attributor] Introduce the concept of query AAs
D106720 introduced features that did not work properly as we could add
new queries after a fixpoint was reached and which could not be answered
by the information gathered up to the fixpoint alone.

As an alternative to D110078, which forced eager computation where we
want to continue to be lazy, this patch fixes the problem.

QueryAAs are AAs that allow lazy queries during their lifetime. They are
never fixed if they have no outstanding dependences and always run as
part of the updates in an iteration. To determine if we are done, all
query AAs are asked if they received new queries, if not, we only need
to consider updated AAs, as before. If new queries are present we go for
another iteration.

Differential Revision: https://reviews.llvm.org/D118669
2022-02-01 01:40:44 -06:00
Johannes Doerfert
ac3ec22df9 [Attributor] Use AAFunctionReachability to determine AANoRecurse
We missed out on AANoRecurse in the module pass because we had no call
graph. With AAFunctionReachability we can simply ask if the function may
reach itself.

Differential Revision: https://reviews.llvm.org/D110099
2022-02-01 01:40:44 -06:00
Johannes Doerfert
5ef18e2421 [Attributor] Use AAValueSimplify to simplify returned values
We should use AAValueSimplify for all value simplification, however
there was some leftover logic that predates AAValueSimplify in
AAReturnedValues. This remove the AAReturnedValues part and provides a
replacement by making AAValueSimplifyReturned strong enough to handle
all previously covered cases. Further, this improve
AAValueSimplifyCallSiteReturned to handle returned arguments.

AAReturnedValues is now much easier and the collected returned
values/instructions are now from the associated function only, making it
much more sane. We also do not have the brittle logic anymore that looks
for unresolved calls. Instead, we use AAValueSimplify to handle
recursion.

Useful code has been split into helper functions, e.g., an Attributor
interface to get a simplified value.

Differential Revision: https://reviews.llvm.org/D103860
2021-07-10 15:52:36 -05:00
Nico Weber
d3e7491333 Revert Attributor patch series
Broke check-clang, see https://reviews.llvm.org/D102307#2869065
Ran `git revert -n ebbe149a6f08535ede848a531a601ae6591cfbc5..269416d41908bb670f67af689155d5ab8eea689a`
2021-07-10 16:15:55 -04:00
Johannes Doerfert
374e573cfc [Attributor] Use AAValueSimplify to simplify returned values
We should use AAValueSimplify for all value simplification, however
there was some leftover logic that predates AAValueSimplify in
AAReturnedValues. This remove the AAReturnedValues part and provides a
replacement by making AAValueSimplifyReturned strong enough to handle
all previously covered cases. Further, this improve
AAValueSimplifyCallSiteReturned to handle returned arguments.

AAReturnedValues is now much easier and the collected returned
values/instructions are now from the associated function only, making it
much more sane. We also do not have the brittle logic anymore that looks
for unresolved calls. Instead, we use AAValueSimplify to handle
recursion.

Useful code has been split into helper functions, e.g., an Attributor
interface to get a simplified value.

Differential Revision: https://reviews.llvm.org/D103860
2021-07-10 12:32:50 -05:00
Johannes Doerfert
fc82409b5c [Attributor] Simplify operands inside of simplification AAs first
When we do simplification via AAPotentialValues or AAValueConstantRange
we need to simplify the operands of an instruction we deconstruct first.
This does not only improve the result, see for example range.ll, but is
required as we allow outside AAs to provide simplification rules via
callbacks. If we do ignore the simplification rules and base other
simplifications on the IR instead we can create an inconsistent state.
2021-07-06 22:41:18 -05:00
Johannes Doerfert
ff256c1376 [Attributor] Derive willreturn based on mustprogress
Since D86233 we have `mustprogress` which, in combination with
`readonly`, implies `willreturn`. The idea is that every side-effect
has to be modeled as a "write". Consequently, `readonly` means there
is no side-effect, and `mustprogress` guarantees that we cannot "loop"
forever without side-effect.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D94125
2021-03-11 23:31:44 -06:00
Johannes Doerfert
9c2074dccb [Attributor][NFC] Update tests after D94741
The update_test_checks script can now check for global symbols and is able
to handle them properly when they differ across prefixes, e.g.,
attribute #0 might be different in different runs.

This patch simply updates all the Attributor tests with the new script.

Reviewed By: sstefan1

Differential Revision: https://reviews.llvm.org/D97906
2021-03-11 23:31:39 -06:00
kuterd
d75c9e61a5 [Attributor] Attributor call site specific AAValueConstantRange
This patch makes uses of the context bridges introduced in D83299 to make
AAValueConstantRange call site specific.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D83744
2021-03-11 01:19:44 +03:00