Just avoid crashing for now, we should be able to replace the blockaddresses
themselves.
BlockAddress::handleOperandChangeImpl assumes it can cast to Function.
The verifier seems nonexistent and the langref isn't particularly explicit
on what's allowed as a blockaddress operand. As far as I can tell bugpoint
isn't doing anything to handle this.
Something low level is broken with BlockAddress handling,
demonstrated by reduce-functions-blockaddress-wrong-function.ll.
The BasicBlock destructor of the deleted function is triggering replacement
of blockaddresses for the kept function in some cases. I've only half debugged
this but it seems like blockaddress is handled too-specially compared to other
Constants. I have tentative patches to allow any constant to be a blockaddress
input, but having the verifier check if it's really a function/block.
https://reviews.llvm.org/D140909
We randomly use outs() or errs(), which makes test logs confusing.
We also randomly add/don't add a line afterward.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D136130
This was done by adding --abort-on-invalid-reduction to remove-function-bodies-used-in-globals.ll and fixing the fallout.
Aliases must have a GlobalValue or ConstantExpr aliasee and the aliasee must be a definition if it's a GlobalValue.
Don't RAUW functions with null if there's an alias pointing to it, and similarly don't delete the body of a function.
Don't delete the entire body of a function when reducing blocks, preserve at least one block.
Also make debugging these sorts of things easier by dumping the module when --abort-on-invalid-reduction triggers.
Reviewed By: regehr
Differential Revision: https://reviews.llvm.org/D131505
Having a separate counting method runs the risk of a mismatch between
the actual reduction method and the counting method.
Instead, create an Oracle that always returns true for shouldKeep(), run
the reduction, and count how many times shouldKeep() was called. The
module should not be modified if shouldKeep() always returns true.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D113537
Use Module& wherever possible.
Since every reduction immediately turns Chunks into an Oracle, directly pass Oracle instead.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D111122
ee6e25e4391a6d3ac0a3c89615474e512f44cda6 changed
the delta pass to skip intrinsics, which means we may end up being
left with declarations of intrinsics, that aren't otherwise referenced
in the module. This is obviously unwanted, do drop them.
These don't really have function bodies to try to eliminate. This also
has a good chance of just producing invalid IR since intrinsics can
have special operand constraints (e.g. metadata arguments aren't valid
for an arbitrary call). This was wasting quite a bit of time producing
and failing on invalid IR when replacing dbg.values with undefs.
It is not enough to replace all uses of users of the function with undef,
the users, we only drop instruction users, so they may stick around.
Let's try different approach - first drop bodies for all the functions
we will drop, which should take care of blockaddress issue the previous
rewrite was dealing with; then, after dropping *all* such bodies,
replace remaining uses with undef (thus all the uses are either
outside of functions, or are in kept functions)
and then finally drop functions.
This seems to work, and passes the *existing* test coverage,
but it is possible that a new issue will be discovered later :)
A new (previously crashing) test added.
There may be other users of a function other than CallInsts,
but what's more important, we can't actually replace function pointer
with undef, because for constants, that would not preserve the type
and RAUW would assert.
In particular, that affects blockaddress, however it proves to be
prohibitively complex to come up with a good test involving blockaddress:
we'd need to both ensure that the function body survives until
this pass, and is not interesting in this pass.
Summary:
I think, this results in much more understandable/readable flow.
At least the original logic was perhaps the most hard thing for me to grasp when taking an initial look on the delta passes.
Reviewers: nickdesaulniers, dblaikie, diegotf, george.burgess.iv
Reviewed By: nickdesaulniers
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83287
llvm::sys::ExecuteAndWait can report errors, so let's make use of that.
Second, while iterating uses of functions to remove, a call can appear
multiple times. Use a SetVector so we don't attempt to erase such a call
twice.
llvm-svn: 371653
Summary:
This also changes all the outs() statements to errs() so the output and
progress streams don't get mixed.
This has been added because D64176 had flaky tests, which I believe were because the reduced file was being catted into `FileCheck`, instead of being pass from STDOUT directly.
Reviewers: chandlerc, dblaikie, xbolva00
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66314
llvm-svn: 369060
Summary: This modification was put in place so the `ReduceMetadata` pass doesn't have to consider debug functions
Reviewers: dblaikie
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66257
llvm-svn: 368934
