Summary:
First stab at quantifier elimination done poorly but fast :)
Easy one: when we know "x = y", and we want to keep x but not y, then
replace y by x everywhere.
Reviewed By: skcho
Differential Revision: D25432207
fbshipit-source-id: 81b142b96
Summary: It's useful for lazily iterating through stuff. Used in the next diff.
Reviewed By: da319
Differential Revision: D25461567
fbshipit-source-id: 040ed12d6
Summary: This diff revises the trace generation of the uninitialized value checker, by introducing a new diagnostics for it.
Reviewed By: jvillard
Differential Revision: D25433775
fbshipit-source-id: 1279c0de4
Summary:
There was a bug where we forgot to mark these values as reachable. In
particular we would forget their arithmetic value as a result.
For example, now we remember that the array access is at an index equal
to 5 in the summary of this function:
```
foo(int a[]) {
a[5] = 42;
}
```
Reviewed By: skcho
Differential Revision: D25430468
fbshipit-source-id: 4acf09842
Summary:
I... kinda forgot about attributes in D25092158 (ab2813e355), which is probably why
impurity was angry that attributes were sometimes missing. Repare this
by adding together the attributes of all the values that are equal.
Reviewed By: skcho
Differential Revision: D25428405
fbshipit-source-id: e5d55b782
Summary:
Address a long-standing embarassing TODO in a minimal way: array indices
are values and when applying a summary we didn't actually bother
translating callee values to caller values. Fix that in a simple way by
just using the current mapping between callee and caller values and
otherwise freshen callee values to avoid clashes with caller values.
Reviewed By: ezgicicek
Differential Revision: D25424013
fbshipit-source-id: 03ca59b9f
Summary:
I wrote an entire diff trying to fix the "bug" that this wasn't needed
so I think this warrants a comment ;)
Reviewed By: ezgicicek
Differential Revision: D25423958
fbshipit-source-id: 414038e40
Summary: The Ondemand entry point `analyze_proc_desc` exists purely to support specialisation under biabduction. After fixing the storing of specialised `proc_desc`s for java it suffices to use `analyze_proc_name` which will work just fine in its place.
Reviewed By: jvillard
Differential Revision: D25421763
fbshipit-source-id: b162feec3
Summary: Whenever the interface functions are called, there is always an execution environment present, so it is safer and better to get rid of the setter/getter reference thing.
Reviewed By: jvillard
Differential Revision: D25421335
fbshipit-source-id: 7110c932b
Summary: This diff gives semantics of dispatch_sync to call the closure parameter.
Reviewed By: jvillard
Differential Revision: D25423175
fbshipit-source-id: a45309073
Summary:
This diff supports inter-procedural uninit analysis in pulse.
* Added `MustBeInitialized` attribute to pre state when an address is read
* Remove `Uninitialized` attribute when callee has `WrittenTo` for the
same address
Reviewed By: jvillard
Differential Revision: D25368492
fbshipit-source-id: cbc74d4dc
Summary:
Skipping the analysis of `std::vector::empty()` caused false positives: in the case where `std::vector::empty()` was called several times ("returning" different values each time), we were not able to prune infeasible paths.
Model `std::vector::empty()` as returning the same value every time it is called.
Reviewed By: ezgicicek
Differential Revision: D23904704
fbshipit-source-id: 52e8a2451
Summary:
Since D20736043 (d84fea52ae) is adding edges from the noreturn function node to exit node, analyzers should
handle the state differently to normal states.
Reviewed By: ezgicicek
Differential Revision: D25402576
fbshipit-source-id: a98e41b0c
Summary:
This diff adds uninitialized value check in pulse. For now, it supports only simple cases,
- declared variables with a type of integer, float, void, and pointer
- malloced pointer variables that points to integer, float, void, and pointer
TODOs: I will add more cases in the following diffs.
- declared/malloced array
- declared/malloced struct
- inter-procedural checking
Reviewed By: jvillard
Differential Revision: D25269073
fbshipit-source-id: 317df9a85
Summary:
This diff adds the ability to skip translation with `... && neg ( pattern)` logic so that we can skip translation of some files if the source does not contain a pattern.
Note that `skip-translation` expects a list of patterns as disjunctions:
https://www.internalfb.com/intern/diffusion/INFER/browse/master/infer/src/IR/inferconfig.ml?commit=76ae5fa0d3376573f6d04814e47ff6b5a9dd9746&lines=74
whereas we want the ability to have conjuctions inside.
## Context
Immutability analysis requires analyzing generated code which might have `Immutable` annotations. When analysing fbandroid, we skip all generated code:
```
"skip-translation": [
{
"source_contains": "generated",
"language": "Java"
}
],
```
However, rather than analyzing all generated code (which might be expensive across all targets) by removing the above, with this diff, we only analyze generated code that doesn't contain e.g. `Immutable` and skip all other generated code as before:
```
"skip-translation": [
{
"source_contains": "generated",
"source_not_contains": "Immutable",
"language": "Java"
}
],
```
Reviewed By: ngorogiannis
Differential Revision: D25328931
fbshipit-source-id: 3ae6ae92a
Summary:
D17710123 (ec62fbefb2) introduced locking to protect the shared pipe to the
originator of the process pool.
D20158845 (a154c8c328) changed the situation by creating a private pipe to the
originator for each worker, so should have removed the locks.
Reviewed By: ezgicicek
Differential Revision: D25370445
fbshipit-source-id: e5f3e4b00
Summary:
See comments added in the code: there's always a chance some unsat
states make it to the end of the execution of an instructions. Before
this diff they would get propagated and executed until some code path
actually bothers to check their satifiability. After this diff we throw
them out at the end of the execution of the first instruction they get
generated in.
An alternative design would be to return Unsat explicitly everywhere we
currently might return `false_`. This would be good too but there's
still a chance we'd generate `false_` and so even if we did that more
significant refactoring, the detection in this diff would still be a
good last line of defense.
Reviewed By: ezgicicek
Differential Revision: D25336042
fbshipit-source-id: a24693596
Summary: When using the restart scheduler incrementing the analyzed count before the analysis itself gives wrong results.
Reviewed By: jvillard
Differential Revision: D25367787
fbshipit-source-id: aed22cc68
Summary:
The frontend of ObjC regarding to captured variable was incorrect: it set capturing mode as
by-reference always, but it actually translaged as if all captured variables were passed with
by-value. This diff fixes this based on the document.
https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Blocks/Articles/bxVariables.html
* global variable: by reference
* local variable: by value
* `static` local variable: by reference
* `__block` local variable: by reference
* parameter: by value
Reviewed By: jvillard
Differential Revision: D25306122
fbshipit-source-id: ec499d705
Summary:
When we know `v1 = v2`, canonicalize `v2 -> v1 * v3 -> v2` to
`v1 -> v1 * v3 -> v1`. Only do this when creating summaries
(and so also when reporting errors) for now.
This only takes into account the equality relation between variables
for now. It needs to be extended to take into account other ways
variables can be equal, eg when two variables are equal to the same
constant or the same term.
Reviewed By: skcho
Differential Revision: D25092158
fbshipit-source-id: 9e589b631
Summary:
Made `AbductiveDomain.summary_of_post` return a Sat/Unsat to make sure
callers filter unsat summaries. Also made `ExitProgram` take a summary
instead of a non-normalized abstract state, which was wrong (mostly
could litter the disjuncts with infeasible paths).
Reviewed By: skcho
Differential Revision: D25277565
fbshipit-source-id: 72dacb944
Summary:
Use the new module to represent both Sat/Unsat from Pulse formulas, and
FeasiblePath/InfeasiblePath from PulseReport.
Reviewed By: jberdine
Differential Revision: D25277566
fbshipit-source-id: 9f8412ca9
Summary:
Until then we mostly ignored aliasing constraints added by callees,
except some of the cases where the aliasing was incompatible with the
current heap. But, we should add `v_caller = v_caller'` any time both
of these (caller) variables are equal to the same callee variable.
These situations are hard to create at the moment since all values in
the pre-condition heap are created distinct and never change. The next
diff introduces canonicalisation of states and merges equal variables,
thus needs this change.
Reviewed By: skcho
Differential Revision: D25092213
fbshipit-source-id: 9fa7b8b53
Summary:
This diff uses Pvar.t in CapturedVar.t, so that
* it can include additional info in Pvar.t
* it can avoid some `Pvar.mk` calls when using the captured variables
Reviewed By: jvillard
Differential Revision: D25331763
fbshipit-source-id: 4e0c2ab4a
Summary:
- Eliminate dead `source` field in `field_data` record.
- Use a 2-level hashtable structure (`procname` -> `source_file` and `source_file` -> `file_data`) to help potentially using an LRU cache for layer 1.
- Use laziness instead of mutability.
- Fixed stale comments
Reviewed By: jvillard
Differential Revision: D25303360
fbshipit-source-id: 68a22d299
Summary:
Models are currently not specialised*. Remove the ability entirely, to allow further changes.
*this is proved by the fact that Infer doesn't crash, which it would if it tried to specialise models, because their procdesc is the already pre-analysed one, and pre-analysing twice a procdesc will crash.
Reviewed By: jvillard
Differential Revision: D25027698
fbshipit-source-id: 76ae5fa0d
Summary:
The code related to "pruned" Topl constraints was scattered in
PulseTopl. Now it's grouped in PulseTopl.Constraint.
Reviewed By: jvillard
Differential Revision: D25273820
fbshipit-source-id: 5d2d0765b
Summary:
When extracting summaries, ask PulseFormula to work harder to prove that
path-conditions are unsat. This reduces the number of false positives.
Reviewed By: jvillard
Differential Revision: D25270609
fbshipit-source-id: 61ef5e8ac
Summary:
Added a topl-max-disjuncts, which is analogous to pulse-max-disjuncts.
Note, however, that the maximum number of states tracked will be the
product of the two limits.
Added also topl-max-conjuncts, which drops Topl states that became too
complex.
Reviewed By: jvillard
Differential Revision: D25240386
fbshipit-source-id: 588c90390
Summary: Tests for the LRU cache now expect a fixed order of key-value pairs in the cache where previously only the set of key-value pairs was considered.
Reviewed By: jvillard
Differential Revision: D25301133
fbshipit-source-id: 0d8077950
Summary:
This is a simple CFG transformation that compresses jumps to jumps
into jumps to the final destination. LLVM's simplifycfg pass seemingly
should have eliminated these, but does not.
Reviewed By: jvillard
Differential Revision: D25196728
fbshipit-source-id: 3288dbd8d
Summary:
Currently the symbolic execution options, obtained from the command
line flags and preanalysis, are passed to the Control entry points as
a record, and then passed around within Control as needed. This diff
simplifies the code in Control by replacing the record mechanism with
an additional functor parameter containing the options. The main
benefit is that the bound option no longer needs to be part of the
analysis state.
This change does make the code in Sledge_cli slightly more
complicated, as it now performs a functor application using a
first-class module computed from the command line flags.
Reviewed By: jvillard
Differential Revision: D25196735
fbshipit-source-id: 80e5d5d62
Summary:
Revise the control-flow exploration scheduling algorithm to fix
several issues. The main difference is to change the priority queue to
keep the control edges on the frontier of exploration in sync with the
states that are waiting to be propagated. This fixes several sorts of
issue where the decision of which control and state joins to perform
was unexpected / wrong. Part of keeping the frontier edges and waiting
states in sync is that the waiting states are associated not only with
a destination block, but the stack of that block. This fixes several
issues.
Combined, these changes lead to the algorithm only attempting joins
for which the pointwise max join on depth maps is correct (with the
caveat of no mathematical proof yet).
Reviewed By: jvillard
Differential Revision: D25196733
fbshipit-source-id: db007fe1f
Summary:
The first-order solver sometimes needs to generate fresh variables to
express the solution of equations. It needs to ensure that these
generated variables do not clash. Before this diff, there was a
confusion where new variables were fresh with respect to only the
current set of "universal" variables. This is wrong, and this diff
adds the full set of variables instead.
Reviewed By: jvillard
Differential Revision: D25196732
fbshipit-source-id: afc56834a
Summary:
It can happen that the actual return variable, which is the name of
the variable in the caller's scope that receives the returned value,
clashes with the formals of the callee. The scope of the return
formula was wrong in this case, as the actual return was outscoped via
existential quantification with the rest of the formals after the
return values was passed.
Reviewed By: jvillard
Differential Revision: D25196727
fbshipit-source-id: 94cf25418
Loc Le
Jules Villard
Sungkeun Cho
Nikos Gorogiannis
Daiva Naudziuniene
Ezgi Çiçek
Joshua Selbo
Radu Grigore
Josh Berdine