This PR relands
[#122992](https://github.com/llvm/llvm-project/pull/122992).
Some machines were failing to run the `reflect-error.ll` test due to the
RUN lines
```llvm
; RUN: not %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown %s -o /dev/null 2>&1 -filetype=obj %}
; RUN: not %if spirv-tools %{ llc -O0 -mtriple=spirv32-unknown-unknown %s -o /dev/null 2>&1 -filetype=obj %}
```
which failed when `spirv-tools` was not present on the machine due to
running the command `not` without any arguments.
These RUN lines have been removed since they don't actually test
anything new compared to the other two RUN lines due to the expected
error during instruction selection.
```llvm
; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv32-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
```
Remove edge iterator parameters from the various helpers that move edges
onto other nodes, and their associated iterator update code, and instead
iterate over copies of the edge lists in the caller loops. This also
avoids the need to increment these iterators at every early loop
continue.
This simplifies the code, makes it less error prone when updating, and
in particular, facilitates adding handling of recursive contexts.
There were no measurable compile time and memory overhead effects for a
large target.
An optimization was added that tries to move the uses of the mflr
instruction away from the instruction itself. However, this doesn't work
when we are using the hashst instruction because that instruction needs
to be run before the stack frame is obtained.
This patch disables moving instructions away from the mflr in the case
where ROP protection is being used.
---------
Co-authored-by: Lei Huang <lei@ca.ibm.com>
This implements a suggestion by Craig in PR #123878. We can move the
worklist management out of the per-instruction work and do it once at
the end of scanning all the instructions. This should reduce repeat
visitation of the same instruction when no changes can be made.
Note that this does not remove the inherent O(N^2) in the algorithm.
We're still potentially visiiting every user of every def.
I also included a guard for unreachable blocks since that had been
mentioned as a possible cause. It seems we've rulled that out, but
guarding for this case is still a good idea.
This fixes a compile-time regression caused by #116645, where an entry
basic block with a very large number of allocas and other instructions
caused SROA to take ~100× its expected runtime, as every alloca (with ~2
uses) now calls this method to find the order of those few instructions,
rescanning the very large basic block every single time.
Since this code was originally written, Instructions now have ordering
numbers available to determine relative order without unnecessarily
scanning the basic block.
Summary:
Previously, managed variables didn't work in rdc mode using the new
driver because we just didn't register them. This was previously ignored
because we didn't have enough space in the current struct format. This
patch amends that by just emitting a struct pair for the two variables
and using the single pointer.
In the future, a more extensible entry format would be nice, but that
can be done later.
This PR replaces some instances of `undef` with `function argument
value` or `poison` or `concrete values` in several tests under
`llvm/test/Transforms/` directory. These changes align with modern LLVM
standards for better-defined behavior and test determinism. If this
small PR is okay and gets merged, I will work on the rest.
This is inspired by [this
project](https://discourse.llvm.org/t/gsoc-2024-remove-undefined-behavior-from-tests/77236/29),
work done on this by @leewei05
There's a regression with one of the bootstrap builds for x86.
I'll revert this while I investigate.
This reverts commit 4df6d3df24ae9cff07c70c96a1663cbba6e1dca5.
I've removed the HasUncountableEarlyExit variable, since we can
already determine whether or not a loop has an early exit by seeing
if we found an uncountable exit.
I have also deleted the old UncountableExitingBlocks and
UncountableExitBlocks lists and replaced them with a single
uncountable edge. This means we don't need to worry about keeping the
list entries in sync and makes it clear which exiting block
corresponds to which exit block.
The default for all other feature combinations remains at zero (i.e. no
streaming hazards). This value may be adjusted in the future (e.g. based
on the processor family), for now, it is set conservatively.
This PR aims to reland work done by @arsenm which was previously
reverted due to some tangentially related scheduler issues as discussed
on #76416.
This PR cherry-picks the original commit (0e46b49de433), and adds
another patch on top with the following changes:
* The code in `updateRegDefsUses` now updates subranges when
subreg-liveness-tracking is enabled.
* When adding an implicit-def operand for the super-register,
the code in `reMaterializeTrivialDef` which tries to remove
undefined subranges should now take into account that the lanes
from the super-reg are no longer undefined.
Co-authored-by: Matt Arsenault <Matthew.Arsenault@amd.com>
