10 Commits

Author SHA1 Message Date
Martin Braenne
f76f6674d8 [clang][dataflow] Use Strict accessors where we weren't using them yet.
This eliminates all uses of the deprecated accessors.

Reviewed By: ymandel, xazax.hun

Differential Revision: https://reviews.llvm.org/D156672
2023-07-31 19:40:04 +00:00
Martin Braenne
1b334a2ae7 [clang][dataflow] Eliminate ReferenceValue.
There are no remaining uses of this class in the framework.

This patch is part of the ongoing migration to strict handling of value categories (see https://discourse.llvm.org/t/70086 for details).

Reviewed By: ymandel, xazax.hun, gribozavr2

Differential Revision: https://reviews.llvm.org/D155922
2023-07-27 13:14:47 +00:00
Martin Braenne
771d7d71df [clang][dataflow] HTMLLogger: Don't crash if CFG contains unreachable blocks.
Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D156411
2023-07-27 13:02:42 +00:00
Martin Braenne
44f98d0101 [clang][dataflow] Eliminate duplication between AggregateStorageLocation and StructValue.
After this change, `StructValue` is just a wrapper for an `AggregateStorageLocation`. For the wider context, see https://discourse.llvm.org/t/70086.

## How to review

- Start by looking at the comments added / changed in Value.h, StorageLocation.h,
  and DataflowEnvironment.h. This will give you a good overview of the semantic
  changes.

- Look at the corresponding .cpp files that implement the semantic changes.

- Transfer.cpp, TypeErasedDataflowAnalysis.cpp, and RecordOps.cpp show how the
  core of the framework is affected by the semantic changes.

- UncheckedOptionalAccessModel.cpp shows how this complex model is affected by
  the changes.

- Many of the changes in the rest of the patch are mechanical in nature.

Reviewed By: ymandel, xazax.hun

Differential Revision: https://reviews.llvm.org/D155446
2023-07-24 13:20:01 +00:00
Sam McCall
fc9821a877 Reland "[dataflow] Add dedicated representation of boolean formulas"
This reverts commit 7a72ce98224be76d9328e65eee472381f7c8e7fe.

Test problems were due to unspecified order of function arg evaluation.

Reland "[dataflow] Replace most BoolValue subclasses with references to Formula (and AtomicBoolValue => Atom and BoolValue => Formula where appropriate)"

This properly frees the Value hierarchy from managing boolean formulas.

We still distinguish AtomicBoolValue; this type is used in client code.
However we expect to convert such uses to BoolValue (where the
distinction is not needed) or Atom (where atomic identity is intended),
and then fold AtomicBoolValue into FormulaBoolValue.

We also distinguish TopBoolValue; this has distinct rules for
widen/join/equivalence, and top-ness is not represented in Formula.
It'd be nice to find a cleaner representation (e.g. the absence of a
formula), but no immediate plans.

For now, BoolValues with the same Formula are deduplicated. This doesn't
seem desirable, as Values are mutable by their creators (properties).
We can probably drop this for FormulaBoolValue immediately (not in this
patch, to isolate changes). For AtomicBoolValue we first need to update
clients to stop using value pointers for atom identity.

The data structures around flow conditions are updated:
- flow condition tokens are Atom, rather than AtomicBoolValue*
- conditions are Formula, rather than BoolValue
Most APIs were changed directly, some with many clients had a
new version added and the existing one deprecated.

The factories for BoolValues in Environment keep their existing
signatures for now (e.g. makeOr(BoolValue, BoolValue) => BoolValue)
and are not deprecated. These have very many clients and finding the
most ergonomic API & migration path still needs some thought.

Differential Revision: https://reviews.llvm.org/D153469
2023-07-07 11:58:33 +02:00
Sam McCall
2d8cd19512 Revert "Reland "[dataflow] Add dedicated representation of boolean formulas" and followups
These changes are OK, but they break downstream stuff that needs more time to adapt :-(

This reverts commit 71579569f4399d3cf6bc618dcd449b5388d749cc.
This reverts commit 5e4ad816bf100b0325ed45ab1cfea18deb3ab3d1.
This reverts commit 1c3ac8dfa16c42a631968aadd0396cfe7f7778e0.
2023-07-05 14:32:25 +02:00
Sam McCall
5e4ad816bf [dataflow] Replace most BoolValue subclasses with references to Formula (and AtomicBoolValue => Atom and BoolValue => Formula where appropriate)
This properly frees the Value hierarchy from managing boolean formulas.

We still distinguish AtomicBoolValue; this type is used in client code.
However we expect to convert such uses to BoolValue (where the
distinction is not needed) or Atom (where atomic identity is intended),
and then fold AtomicBoolValue into FormulaBoolValue.

We also distinguish TopBoolValue; this has distinct rules for
widen/join/equivalence, and top-ness is not represented in Formula.
It'd be nice to find a cleaner representation (e.g. the absence of a
formula), but no immediate plans.

For now, BoolValues with the same Formula are deduplicated. This doesn't
seem desirable, as Values are mutable by their creators (properties).
We can probably drop this for FormulaBoolValue immediately (not in this
patch, to isolate changes). For AtomicBoolValue we first need to update
clients to stop using value pointers for atom identity.

The data structures around flow conditions are updated:
- flow condition tokens are Atom, rather than AtomicBoolValue*
- conditions are Formula, rather than BoolValue
Most APIs were changed directly, some with many clients had a
new version added and the existing one deprecated.

The factories for BoolValues in Environment keep their existing
signatures for now (e.g. makeOr(BoolValue, BoolValue) => BoolValue)
and are not deprecated. These have very many clients and finding the
most ergonomic API & migration path still needs some thought.

Differential Revision: https://reviews.llvm.org/D153469
2023-07-05 13:54:32 +02:00
Sam McCall
b56b15ed71 [dataflow] HTMLLogger - show the value of the current expr
Differential Revision: https://reviews.llvm.org/D148949
2023-04-26 17:15:23 +02:00
Sam McCall
0304aa25e0 [dataflow] allow specifying path to dot with $GRAPHVIZ_DOT
I'd like to use this in a CI system where it's easier to tell the
program about paths than manipulate $PATH.
2023-04-21 05:29:11 +02:00
Sam McCall
a443b3d18e [dataflow] add HTML logger: browse code/cfg/analysis timeline/state
With -dataflow-log=/dir we will write /dir/0.html etc for each
function analyzed.

These files show the function's code and CFG, and the path through
the CFG taken by the analysis. At each analysis point we can see the
lattice state.

Currently the lattice state dump is not terribly useful but we can
improve this: showing values associated with the current Expr,
simplifying flow condition, highlighting changes etc.

(Trying not to let this patch scope-creep too much, so I ripped out the
half-finished features)

Demo: 9718fdd484/analysis.html

Differential Revision: https://reviews.llvm.org/D146591
2023-04-19 15:37:06 +02:00