3 Commits

Author SHA1 Message Date
Johannes Doerfert
c2281f1565 [Attributor] Introduce AAPointerInfo
This patch introduces AAPointerInfo which tracks the uses of a pointer
and places them in "bins" based on their offset from the base and access
size.

As with other AAs, any pointer can be tracked but it is up to the user
to make sense of the results. The user in this patch is AAValueSimplify
and AAPotentialValues which both utilize AAPointerInfo to determine the
value of a load. For now, this is restricted to loads of allocas and
internal globals. Through the use of AAPointerInfo and the "bins" we can
track struct members separately. The users also know that storing only
zeros (at unknown indices) will result in loading only 0 (from unknown
indices). Other than that, the users are flow and context insensitive
(for now).

To deal with the "bins" more easily, AAPointerInfo provides a
forallInterfearingAccesses that applies a callback on all accesses
that might interfere with a given load or store.

Differential Revision: https://reviews.llvm.org/D104432
2021-07-19 22:48:35 -05:00
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
Johannes Doerfert
d39f574dcc [Attributor][FIX] Properly promote arguments pointers to arrays
When we promote pointer arguments we did compute a wrong offset and use
a wrong type for the array case.

Bug reported and reduced by Whitney Tsang <whitneyt@ca.ibm.com>.
2020-10-29 00:45:32 -05:00