The IR from https://github.com/llvm/llvm-project/issues/57368 results
in an assert firing when trying to create a runtime check for the
forked pointer. One of the forks is fine since it's loop invariant,
but the other is a scAddExpr (containing a scAddRecExpr, so not
invariant) when RtCheck::insert expects a scAddRecExpr.
This is a simple fix to just avoid forks which aren't AddRec or
loop invariant. We can allow it as a forked pointer later with
more work.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D133020
This updates the naming for the LAA printing pass to be in line with
most other analysis printing passes.
The old name has come up as confusing multiple times already, e.g. in
D131924.
Handle cases where a forked pointer has an add or sub instruction
before reaching a select.
Reviewed By: fhahn
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D130278
Adds new tests for add and sub instructions before reaching a select.
Also adds tests using different bit widths for memory, including
non-power-of-two integers.
This builds on the previous forked pointers patch, which only accepted
a single select as the pointer to check. A recursive function to walk
through IR has been added, which searches for either a loop-invariant
or addrec SCEV.
This will only handle a single fork at present, so selects of selects
or a GEP with a select for both the base and offset will be rejected.
There is also a recursion limit with a cli option to change it.
Reviewed By: fhahn, david-arm
Differential Revision: https://reviews.llvm.org/D108699
* Converted tests to use opaque pointers
* Added suggested test for inbounds GEP
* Added a test for forks on both the base and offset terms of a GEP
* Added a test for a select of a select
* Added a test for a GEP with >2 operands
* Added a test for vector GEPs
This reverts commit 7aa8a67882.
This version includes fixes to address issues uncovered after
the commit landed and discussed at D11448.
Those include:
* Limit select-traversal to selects inside the loop.
* Freeze pointers resulting from looking through selects to avoid
branch-on-poison.
Scaffolding support for generating runtime checks for multiple SCEV expressions
per pointer. The initial version just adds support for looking through
a single pointer select.
The more sophisticated logic for analyzing forks is in D108699
Reviewed By: huntergr
Differential Revision: https://reviews.llvm.org/D114487
Graham Hunter