This makes it easier to reduce llvm-reduce with llvm-reduce to filter
cases where the input reduced too much.
Not sure if it's possible to test the exit code in lit.
If we are trying to simplify branch conditions to true, ignore branches
already set to a constant true. If we are simplifying to constant false,
ignore the already constant false cases. This saves steps in this edge
case, and avoids the side effect of running simplifycfg on blocks we
did not intend to modify.
The IR verifier will fail if there are any convergent calls without
a convergencectrl bundle, if there are any convergencectrl bundles.
With the current verifier rules, we would need to drop all the instances
of convergencectrl in the function as a set, and strip all the
convergence
token intrinsics. As such, I think it would be more appropriate to have
a
separate convergence reduction pass.
Try to reduce individual subtarget features in the "target-features"
attribute. This attempts a textual removal of the fields in the string,
not a semantic removal. Typically there's a lot of redundant feature spam
in the feature list implied by the target-cpu (which I really wish clang
would stop emitting). If we could parse these out, we could easily drop
the fields without testing anything.
The current API doesn't have a way to unset it. The query returns
an optional, but the set doesn't. Alternatively I could switch the
set to also use optional.
Not sure this is the right place to put it. This is a property
of GlobalVariable, not GlobalValue. But the ReduceGlobalVars
reduction tries to delete the value entirely.
Avoid capitalized Error. This loses the "Error constructing pass pipeline"
part, and just forwards the error to the default report_fatal_error case. Not
sure if it's worth trying to keep.
The coding standards states that error messages should start with
a lowercase. Also use WithColor, and add missing test coverage for
the failed to write to output file case.
If the interestingness script is flaky, we should not assert. Print
a warning, and continue. This could still happen as a result of an
llvm-reduce bug, so make a note of that.
Add a --skip-verify-interesting-after-counting-chunks option to
avoid the extra run of the reduction script, and to silence the
warning.
In undefined mismatch cases, this was fixing the callsite to use the calling
convention of the new function. Preserve the original wrong callsite's calling
convention.
The attribute APIs make this cumbersome. There seem to be missing
overloads using AttrBuilder for the function attrs. Plus there doesn't
seem to be a direct way to set the function attrs on the call.
We can use *Set::insert_range to collapse:
for (auto Elem : Range)
Set.insert(E);
down to:
Set.insert_range(Range);
In some cases, we can further fold that into the set declaration.
So far I've been unsuccessful in finding an example where the used constant
value is directly observed in the output. This avoids an assert in an intermediate
step of value replacement.
As part of the "RemoveDIs" project, BasicBlock::iterator now carries a
debug-info bit that's needed when getFirstNonPHI and similar feed into
instruction insertion positions. Call-sites where that's necessary were
updated a year ago; but to ensure some type safety however, we'd like to
have all calls to getFirstNonPHI use the iterator-returning version.
This patch changes a bunch of call-sites calling getFirstNonPHI to use
getFirstNonPHIIt, which returns an iterator. All these call sites are
where it's obviously safe to fetch the iterator then dereference it. A
follow-up patch will contain less-obviously-safe changes.
We'll eventually deprecate and remove the instruction-pointer
getFirstNonPHI, but not before adding concise documentation of what
considerations are needed (very few).
---------
Co-authored-by: Stephen Tozer <Melamoto@gmail.com>
This relands commit #115111.
Use traditional way to update post dominator tree, i.e. break critical
edge splitting into insert, insert, delete sequence.
When splitting critical edges, the post dominator tree may change its
root node, and `setNewRoot` only works in normal dominator tree...
See
6c7e5827ed/llvm/include/llvm/Support/GenericDomTree.h (L684-L687)