Summary:
The translation of `switch` cases needs to insert nodes around the
translation of each `case` sub-statement, so we need to force node
creation in these sub-statements so the nodes around it can be connected
to the translation of the sub-statements.
Also added more logging I found useful when debugging that.
Reviewed By: da319
Differential Revision: D24991455
fbshipit-source-id: d3a622142
Summary:
In all other places, we index params from 0, but accidentally recorded
the wrong number in json. It was because of the confusion between index
and user-visible param position that we show for the user message.
This diff fixes it: now we use 0-based indices internally (but of course still
report 1-based ones in the error message).
Reviewed By: artempyanykh
Differential Revision: D24916878
fbshipit-source-id: 45532c5ff
Summary:
Split the translation of return more aggressively between:
1. the instruction that has to happen before the translation of the sub-expr
2. the sub-expr
3. the instruction that has to happen after the sub-expr
This is needed for the next diff which creates potentially large CFGs in
(2).
Reviewed By: da319
Differential Revision: D24954071
fbshipit-source-id: a7e7e2527
Summary: Model `folly::Optional::get_pointer` which returns an address to a value if exists or `nullptr` if empty.
Reviewed By: jvillard
Differential Revision: D24935677
fbshipit-source-id: 9d990fe07
Summary:
We deliberately stopped as soon as an error was detected when applying a
function call. This is not good as other pre/posts of the function may
apply cleanly, which would allow us to cover more behaviours of the
code.
Went on a bit of a refactoring tangeant while fixing this, to clarify
the `Ok None`/`Ok Some _`/`Error _` datatype returned by PulseInterproc.
Now we report errors as soon as we find them during function calls but
continue accumulating specs afterwards.
Reviewed By: da319
Differential Revision: D24888768
fbshipit-source-id: d5f2c29d7
Summary:
Communicate new facts from the arithmetic domain to the memory domain to
detect contradictions between the two.
Reviewed By: jberdine
Differential Revision: D24832079
fbshipit-source-id: 2caf8e9af
Summary:
This is several inter-connected changes together to keep the tests
happy.
The ConditionalOperator `b?t:e` is translated by first creating a
placeholder variable to temporarily store the result of the evaluation
in each branch, then the real thing we want to assign to reads that
variable. But, there are situations where that changes the semantics of
the expression, namely when the value created is a struct on the stack
(eg, a C++ temporary). This is because in SIL we cannot assign the
*address* of a program variable, only its contents, so by the time we're
out of the conditional operator we cannot set the struct value
correctly anymore: we can only set its content, which we did, but that
results in a "shifted" struct value that is one dereference away from
where it should be.
So a batch of changes concern `conditionalOperator_trans`:
- instead of systematically creating a temporary for the conditional,
use the `trans_state.var_exp_typ` provided from above if available
when translating `ConditionalOperator`
- don't even set anything if that variable was already initialized by
merely translating the branch expression, eg when it's a constructor
- fix long-standing TODO to propagate these initialization facts
accurately for ConditionalOperator (used by `init_expr_trans` to also
figure out if it should insert a store to the variable being
initialised or not)
The rest of the changes adapt some relevant other constructs to deal
with conditionalOperator properly now that it can set the current
variable itself, instead of storing stuff inside a temp variable. This
change was a problem because some constructs, eg a variable declaration,
will insert nodes that set up the variable before calling its
initialization, and now the initialization happens *before* that setup,
in the translation of the inner conditional operator, which naturally
creates nodes above the current one.
- add a generic helper to force a sequential order between two
translation results, forcing node creation if necessary
- use that in `init_expr_trans` and `cxxNewExpr_trans`
- adjust many places where `var_exp_typ` was incorrectly not reset when translating sub-expressions
The sequentiality business creates more nodes when used, and the
conditionalOperator business uses fewer temporary variables, so the
frontend results change quite a bit.
Note that biabduction tests were invaluable in debugging this. There
could be other constructs to adjust similarly to cxxNewExpr that were
not covered by the tests though.
Added tests in pulse that exercises the previous bug.
Reviewed By: da319
Differential Revision: D24796282
fbshipit-source-id: 0790c8d17
Summary:
The starvation domain keeps a domain element per distinct pair of lock object and source location. This was used to counteract the imprecision of implicit Quandary-style traces. Starvation has used explicit traces for a long time now, so keeping all these elements is expensive (in fact, in some cases exponential) and of no value. Now, lock object identity is the only distinguishing feature of a domain element.
Also, fix some pretty printing for debugging purposes.
Reviewed By: jvillard
Differential Revision: D24829306
fbshipit-source-id: 22e12f9c1
Summary: We recently introduced a more precise model for constructing an optional from a value by making a shallow copy. However, this introduced Use After Delete false positives. For now, we go back to a less precise model by creating a fresh value. A proper model would be to either make a deep copy or call the copy constructor for a value. We will address this in the following diff.
Reviewed By: jvillard
Differential Revision: D24826749
fbshipit-source-id: 3e5e4edeb
Summary: Refactor `folly::Optional` models to make them easier to reuse for `std::optional`
Reviewed By: jvillard
Differential Revision: D24760053
fbshipit-source-id: f665e84c8
Summary:
If the issue one of:
- Field Not Nullable
- Field Not Initialized
- Field Overannotated,
we record field_name to .json result.
NoTE: Design choice for representation. For Field Not Initialized and Field Overannotated
this is always internal (relative to the class) field, but for Field Not
Nullable it can be either internal or external. We could have a
structured output, or always output full name. I preferred to output
short name for convenience of the main usacase I am anticipating.
NOTE: not to be confused with the case where the field is nullable but
we e.g. try to dereference it. This is indirectly related to the issue
(can be several such fields for starters) and if we one day output it,
it will be provided in a separate way (similarly to how we output
nullable_methods).
Reviewed By: artempyanykh
Differential Revision: D24730320
fbshipit-source-id: c995ec221
Summary:
We never tested params dependent on things (tested only things dependend
on params).
Reviewed By: artempyanykh
Differential Revision: D24726858
fbshipit-source-id: a0861cfc3
Summary:
Since we report issues types without a prefix (e.g. ERADICATE_) and
with spaces we should also allow for prefix-less issue types in
SuppressLint, so both should work
- SuppressLint("eradicate-field-not-initialized")
- SuppressLint("Field Not Initialized")
Reviewed By: jvillard
Differential Revision: D24760341
fbshipit-source-id: 1590cf6d0
Summary:
There is a feature in Nullsafe that is interfering with "annotation
graph" feature. Because of this we would not detect provisional
violations for misuses of params of equals() (They will be recorded
as user facing rather than provisional issues).
This diff turns this feature off for annotation graph mode.
Reviewed By: artempyanykh
Differential Revision: D24726655
fbshipit-source-id: 4b7577667
Summary:
Virtual "this" invisible param exists in the annotated signature, but
does not exist in some other places, which causes a lot of annoyance in
different places.
This diff does not intend to solve all this, but makes one step forward.
1/ AnnotatedNullability now explicitly distincts normal params and
VirtualThis.
2/ AnnotatedSignature accounts for this via: a) not having redundant
fake annotation points b) having corrent param indices (those were off
by 1 in non-virtul methods).
Reviewed By: artempyanykh
Differential Revision: D24726480
fbshipit-source-id: fdb8bb0fb
Summary: This is a complex enough feature so iterating on it in a safe manner will be useful.
Reviewed By: artempyanykh
Differential Revision: D24725406
fbshipit-source-id: 81b247143
Summary: `folly::Optional::value()` returns a reference, hence an error was shown when the actual value was being accessed. Since `value()` throws an exception in case of `folly::none`, we want to show the error message at the call site of `value()`. We do this by dereferencing the result of `value()` in the model.
Reviewed By: jvillard
Differential Revision: D24702875
fbshipit-source-id: ca9f30349
Summary:
The problem in Reporting.ml:log_issue_from_summary is that it merely
checks the presence of `SuppressLint` annotation on method's body to
decide whether to log or not the issue. This means that regardless of
issue types specified in `SuppressLint`, all issues on such method will
get blocked.
Here we fix that.
Reviewed By: ngorogiannis, mityal
Differential Revision: D24726604
fbshipit-source-id: c9cae3833
Summary:
Before we were creating a fresh internal value when we were constructing `folly::Optional`. This diff models `folly::Optional` constructor more precisely by copying the given value.
There was also a missing dereference in the model of `value_or`
Reviewed By: jvillard
Differential Revision: D24621016
fbshipit-source-id: c86d3c157
Summary:
Namely `enumerateObjectsUsingBlock` which takes a collection and a block as an arg and the iterates over the collection and applies the block to each element of the collection.
This is a common way to iterate over Objc collections, so let's add a model for it.
Reviewed By: skcho
Differential Revision: D24604590
fbshipit-source-id: 1ceeb4b40
Summary:
This diff revises the translation of message expression's arguments in ObjC frontend. In the
frontend, it massages the arguments when calling a static method, so the class or object value is
not given to the static method as the first parameter.
The problem is that it used a raise-exception-and-catch way to detect where we remove the first
parameter. This way of using an exception is not only hard to understand, but also incorrectly
removed the first parameter, with breaking abstract semantics sometimes. (See the added test.) This diff
avoids using the exception.
Reviewed By: jvillard
Differential Revision: D24565513
fbshipit-source-id: 0a84ca394
Summary:
The `make clean` did not remove objects and dot files, so
```
infer/tests/codetoanalyze/objc/frontend$ make test
infer/tests/codetoanalyze/objc/frontend$ make clean
infer/tests/codetoanalyze/objc/frontend$ make test
```
the second `make test` did nothing. This diff adds additional regular
expressions to clean all objects and dot files generated.
Reviewed By: ngorogiannis
Differential Revision: D24566169
fbshipit-source-id: b8c50c922
Summary: This diff fixes on-demand symbolic value generation of a class that inherits NSEnumerator.
Reviewed By: ngorogiannis
Differential Revision: D24504955
fbshipit-source-id: bcb20e8aa
Summary:
This diff replaces overridden method calls in ObjC when possible, ie the first parameter of the
method has a sub-class type of the method's class. For example,
when `MyEnumerator` is a sub-class of `NSEnumerator` and there is overridden `nextObject`,
```
[my_enumerator nextObject]
```
in Sil, it was translated to like
```
NSEnumerator.nextObject(my_enumerator : MyEnumerator*)
```
and the analyzer missed the overridden method. This diff replaces the function call to
```
MyEnumerator.nextObject(my_enumerator : MyEnumerator*)
```
Reviewed By: ezgicicek
Differential Revision: D24477290
fbshipit-source-id: 6842a76f8
Summary: Model `folly::Optional::value_or(default)` to return value if not-empty and `default` if empty.
Reviewed By: jvillard
Differential Revision: D24539456
fbshipit-source-id: cc9e176cc
Summary:
This diff revises `nextObject` model to handle multiple symbolic enumerators. Instead joining the
symbolic offsets of them, which sometimes introduces top, it sums the offsets. This is a sound &
conservative semantics since they are all non-negative integers.
Reviewed By: ezgicicek
Differential Revision: D24474513
fbshipit-source-id: 6707aa907
Summary:
This diff revises memory model of enumerator in ObjC to enable passing it as a parameter.
The cost checker was not able to analyze a function precisely when it gets an enumerator as a
parameter because the offset of an enumerator was available only when the analyzer knew the correct
relation between the enumerator and an array.
This diff simplifies the enumerator to have a similar value with `array->elements`, so its offset can
be taken without the relation between enumerator and array to get them.
Reviewed By: ezgicicek
Differential Revision: D24446574
fbshipit-source-id: 27cdc051e
Summary:
This diff adds an option hiding function pointers in costs to users: `cost-suppress-func-ptr` is
true by default.
Reviewed By: ezgicicek
Differential Revision: D24448212
fbshipit-source-id: 88f6b5ea1
Summary:
This diff adds a model for NSFileManager.contentsOfDirectoryAtURL as returning a constant-length
collection.
The analyzer cannot know files in a directory. We have some options to handle such unknown data.
1. Use `Unknown` value, ie `top`
2. Use a symbolic value
3. Use a constant value
We had been used the first option. An upside of this is that the analyzer can remain as sound.
However, a downside of this is the top value can be propagated to other procedures, making their
costs top, thus we may miss some cost changes of them.
The second option is to introduce a symbolic value, ie. that for the number of files. A problem is
that the symbolic value will never be concretized. As a result, the symbol can be propagated to
other procedures, increasing the coefficient of the complexity or making top costs. Note that handling multiple
symbols is somewhat limited in Inferbo's interval domain.
The last option is to introduce a constant value. I think this is the best approach we can take among above.
Even though we may have FNs when there are a lot of files in a directory, we cannot reason or expect about
that at the analysis time anyway.
Reviewed By: ezgicicek
Differential Revision: D24418099
fbshipit-source-id: bf8cf3538
Summary: This diff adds closure symbols to operation/allocation costs, when function pointer is called.
Reviewed By: ezgicicek
Differential Revision: D24308550
fbshipit-source-id: 6c5889d41
Summary:
This diff extended the polynomial domain to include symbols for closure calls.
When the closure symbol is added to the polynomial? Unknown closure is called inside a function
like,
```
foo() {
self->closure_field();
}
```
Thus, the cost of `foo` becomes `|self->flosure_field|`, rather than unknown. (Note that this
semantics is added only for autoreleasepool size at the moment.)
When the symbol is instantiated? `foo` is called with correct closure contexts.
```
goo() {
self->closure_field = ^(){ ... };
foo();
}
```
The summary of `goo` will have instantiated summary of the closure.
Reviewed By: ezgicicek
Differential Revision: D23992590
fbshipit-source-id: d1d228403
Summary:
In ObjC, `NSObject.copy` returns the object returned by `copyWithZone:` on the given class. This method must be implemented if the class complies with `NSCopying` protocol. Since we don't have access to `NSObject`'s code, to follow calls into `copyWithZone:`, we replace such `copy` calls with calls to `copyWithZone:` when a) such a method exists in the class and b) the class conforms to `NSCopying` protocol.
This is done in the preanalysis because
- we need to know if there is a `copyWithZone:` method in the class.
- so that other analyses also benefit (as opposed to doing this in cost and inferbo models).
Note that `NSObject` doesn't itself conform to `NSCopying` but all its subclasses must confrom to the protocol and support the same behavior as above.
https://developer.apple.com/documentation/objectivec/nsobject/1418807-copy
Similarly for `mutableCopy` -> `mutableCopyWithZone:` for classes implementing `NSMutableCopying` protocol.
Reviewed By: skcho
Differential Revision: D24218102
fbshipit-source-id: 42900760e
Summary: Model it similar to `NSArray.initWithArray` as copying from the given dictionary elements. Removes a FP as expected.
Reviewed By: ngorogiannis
Differential Revision: D24136868
fbshipit-source-id: ed31c3c8f
Summary:
This diff extends inferbo's domain to include closure values. The goal of this extension is to
follow missing semantics where closures are handled as values, for example, a closure is assigned to
an object field, then it is got later to call.
Due to the bottom-up nature of the analyzer, sometimes we don't know which values are written in a
field, which is the same for the other non-closure values.
Reviewed By: ezgicicek
Differential Revision: D23932186
fbshipit-source-id: 4a575d0de
Summary: Dispatch & function call mechanism was so jumbled up together. Let's refactor it to be cleaner.
Reviewed By: skcho
Differential Revision: D24049889
fbshipit-source-id: 42a218016
Summary:
Take another page from the Incorrectness Logic book and refrain from reporting issues on paths unless we know for sure that this path will be taken.
Previously, we would report on paths that are merely *not impossible*. This goes very far in the other direction, so it's possible we'll want to go back to some sort of middle ground. Or maybe not. See the changes in the tests to get a sense of what we're missing.
Reviewed By: ezgicicek
Differential Revision: D24014719
fbshipit-source-id: d451faf02
Summary: We add a naive model for `forEach` idiom for Java's Iterable and Maps. The model is naive because it doesn't take the cost of the lambda into account. This will be fixed later.
Reviewed By: da319
Differential Revision: D23868203
fbshipit-source-id: 37d169c6f
Summary:
The problem: current enumerator semantics does not work on symbolic enumerator that is given as a
parameter.
Reviewed By: ezgicicek
Differential Revision: D24017059
fbshipit-source-id: 378e75bb0
Summary:
This can be used by additional tooling for further analysis (e.g.
codemods, autofixes, etc).
Reviewed By: ngorogiannis
Differential Revision: D23987694
fbshipit-source-id: b9fa343ac
Summary:
This diff keeps closure parameters in closure-specializated procedures.
What the closure-specialization is doing is a propagation of concrete closures. For example, it
translates:
```
foo(block b) {
b();
}
goo() {
foo(^{...});
}
```
to
```
foo_new() {
(^{...})();
}
goo() {
foo_new();
}
```
However, if `foo` addresses `b` as a normal value like
```
foo(block b) {
block c = b;
}
```
this is translated to
```
foo_new() {
block c = b;
}
```
Note that the closure parameter of `foo` is removed, thus `b` becomes a free variable. Not good.
To avoid the situation, this diff keeps the closure parameters intact.
Reviewed By: da319
Differential Revision: D23905580
fbshipit-source-id: 014989fbf
Summary: Subtle false positives and negatives in Hil make Sil preferable. This diff gets rid of the CFG-emulation of Hil, while still using Hil expressions.
Reviewed By: da319
Differential Revision: D23815026
fbshipit-source-id: 731a6d299
Summary: Without curly braces, it is declaration of globals, not fields.
Reviewed By: ezgicicek
Differential Revision: D23866604
fbshipit-source-id: dd685c8d6
Summary:
The previous diffs recorded it for the case when the unvetted value is
dereferenced or otherwise used wrongly. This case finishes the work,
recording the needed signature for the remaining case (when the
offending third party has a non-nullable param with nullable passed
inside)
Reviewed By: ngorogiannis
Differential Revision: D23706679
fbshipit-source-id: e6f641223
Summary: This diff adds a test, in which autoreleasing lambda is written in an object field, then called later. The test is not analyzed precisely because it cannot follow that a lambda value is written to a field of an object as of now.
Reviewed By: ezgicicek
Differential Revision: D23843089
fbshipit-source-id: 62ba153aa
Summary:
This diff substitutes closure parameter when it is given via variable. For example,
```
x = ^{ ... }
foo(x)
```
this diff substitutes the closure variable `x`,
```
x = ^{ ... }
foo(^{ ... })
```
so that the specialization of `foo` can be done by `CCallSpecializaedWithClosures.process`.
Reviewed By: jvillard
Differential Revision: D23814595
fbshipit-source-id: a89f1530f
Summary:
Upgrade to latest clang release, needed for xcode12.
clang-8/9 won't be able to read the Xcode 12 SDK since there's annotations that will fail compilation.
Also removing unused (and hard to compile) binary `ast_exporter_bin` from facebook-clang-plugins/libtooling.
Reviewed By: ngorogiannis
Differential Revision: D23780089
fbshipit-source-id: 2314125a9
Summary:
This diff add a model of `NSArray.index_of_object_passing_test` in
autoreleasepool size model.
Worst case autorelease cost is "array size x cost of given test function (lambda)".
Reviewed By: ezgicicek
Differential Revision: D23785165
fbshipit-source-id: 95ec9700a
Summary:
Nullifying these leads to observable side-effects, like in the added
test.
Reviewed By: da319
Differential Revision: D23759756
fbshipit-source-id: 559a6486b
Summary: ObjC objects can be added to autorelease pool by `CFAutorelease`.
Reviewed By: ezgicicek
Differential Revision: D23625632
fbshipit-source-id: 694e5bffb
Summary:
This diff regards some methods of NSKeyedUnarchiver as autorelease, because they may call
autorelease.
Reviewed By: ezgicicek
Differential Revision: D23600232
fbshipit-source-id: a9fc1cc56
Summary:
This diff increases autoreleasepool size when
* caller is non-ARC-compiled
* callee is ARC-compiled
* return type is a pointer to objc object
To distinguish non-ARC-/ARC-compiled:
* extended `translation_unit_decl_info` to have a boolean field `is_objc_arc_on`
* then copied it to `ProcAttributes.t` for each procedures.
Reviewed By: ezgicicek
Differential Revision: D23565003
fbshipit-source-id: dee22ea82
Summary: Structs captured both by reference or by value should have reference in their type. Struct captured by value should first call copy constructor. In this diff we fix the type of the captured variable to include reference. Copy constructor injection is left for the future.
Reviewed By: jvillard
Differential Revision: D23688713
fbshipit-source-id: d13748b5d
Summary: Variables captured without initialization do not have correct type inside lambda's body. This diff sets the correct type of captured reference variables inside procdesc and makes sure the translation of captured variables is correct. The translation of lambda's body will then take into account the type of captured var from procdesc.
Reviewed By: jvillard
Differential Revision: D23678371
fbshipit-source-id: ed16dc978
Summary: Add missing reference to the type of variable captured by reference without initialization.
Reviewed By: jvillard
Differential Revision: D23567685
fbshipit-source-id: b4e2ac0b6
Summary:
We were missing assignment to captured variables with initializers.
Consider the following example:
```
S* update_inside_lambda_capture_and_init(S* s) {
S* object = nullptr;
auto f = [& o = object](S* s) { o = s; };
f(s);
return object;
}
```
which was translated to
```
VARIABLE_DECLARED(o:S*&);
*&o:S*&=&object
*&f =(_fun...lambda..._operator(),([by ref]&o &o:S*&))
```
However, we want to capture `o` (which is an address of `object`), rather `&o` in closure.
After the diff
```
VARIABLE_DECLARED(o:S*&);
*&o:S*&=&object
n$7=*&o:S*&
*&f =(_fun...lambda..._operator(),([by ref]n$7 &o:S*&))
```
Reviewed By: jvillard
Differential Revision: D23567346
fbshipit-source-id: 20f77acc2
Summary:
If the issue is related to the use of an unvetted third party method
that can not be trusted, we record this fact.
Reviewed By: ngorogiannis
Differential Revision: D23705626
fbshipit-source-id: 851328fe5
Summary:
It was inconsistent before (we recorded it only for meta issues).
Now we always record it, which will simplify further diffs.
In the next diffs, we are going to add more fields inside `nullsafe_extra`.
Reviewed By: ngorogiannis
Differential Revision: D23705592
fbshipit-source-id: 8bbb0e7c8
Summary:
This can be useful to make pulse forget about tricky parts of the code.
Treat "skipped" procedures as unknown so heuristics for mutating the
return value and parameters passed by reference are applied.
Reviewed By: ezgicicek
Differential Revision: D23729410
fbshipit-source-id: d7a4924a8
Summary: This diff selects an autorelease trace that has a bigger polynomial.
Reviewed By: ezgicicek
Differential Revision: D23731155
fbshipit-source-id: 243591583
Summary:
This diff reports paths under the xcode isysroot as relative in tests.
This was a problem when another machine that has a different isysroot
directory is running the test.
Reviewed By: ezgicicek
Differential Revision: D23729222
fbshipit-source-id: 4e9681f65
Summary:
Handle the case of
- computing the range of `[lb, ub]` where `lb` contains length path and `ub` is constant. E.g. `[a.length, 2]` would give `3` range
- simplifying `c1 +/- min(c2, a.length)` to `c1 +/- min(c2, 0)`
since the length of a collection/array is always nonnegative.
This also removes some existing FPs in tests results.
Facebook
Context: we stumbled upon this issue in ObjC results TV109717121 which is corresponding to the added test case.
Reviewed By: skcho
Differential Revision: D23648807
fbshipit-source-id: 1e89ea246
Summary: This diff adds trace field for autoreleasepool size. Unlike to the other checkers, eg inferbo and operation cost, the autoreleasepool size checker should have traces for constants.
Reviewed By: ezgicicek
Differential Revision: D23678084
fbshipit-source-id: 35e6cf5f5
Summary:
The `attr_kind` column has now exactly two possible values: defined and undefined (since D22187238 (61ae2d1e1b)). This is also what should be stored in the field `is_defined` in the procedure attributes. Finally, the cfg can be `NULL` or not. This diff makes all three of these agree, in order to allow for the removal of the `attr_kind` column up the stack, since it will be equivalent to `cfg is NOT NULL`.
The changes in the tests indicate improved correctness: previously, specialising a modelled callee would result in a dummy entry in the procedures table, because all clang procedures were given a procdesc, so the specialisation would specialise the empty procdesc. Now, the model is not shadowed by the specialised dummy procdesc, and is specialised itself (and that's why it also ends up in the capture DB, which is slightly counter-intuitive).
Reviewed By: jvillard
Differential Revision: D23536931
fbshipit-source-id: 983216cb6
Summary:
We defined cost's plus as "zero+unreachable = unreachable" for the operation cost. The meaning of
the zero cost is that no statment is analyzed yet, and the unreachable(bottom) cost means a program
point is analyzed as unreachable. We thought "zero+unreachable" happens in very specific cases we
need to check, or due to an analyzer bug. For debugging purpose, we defined it to return more
specific unreachable cost.
However, in allocation/autoreleasepool costs, the zero cost is not very special value. If there is
no alloc/autorelease calls, they can have the zero cost. "zero+unreachable = unreachable" doesn't
make sense there.
This diff changes the plus as "zero+unreachable = zero" for the non-operation costs.
Reviewed By: ezgicicek
Differential Revision: D23578869
fbshipit-source-id: 5392eca1c
Summary: This diff adds some tests run with ARC/non-ARC compiled objective-c sources.
Reviewed By: ezgicicek
Differential Revision: D23542135
fbshipit-source-id: 8e089666b
Summary:
This diff adds a new experimental checker for detecting size of objects in autorelease pool in ObjC. The basic mechanism is almost the same with the previous cost calculation:
* Autorelease pool size is increased at explicit `autorelease` call
* Autorelease pool size is set as zero by the `autoreleasepool` block.
While it only supports the explicit calls as of now, we will extend the checker to handle more cases in the following diffs.
Reviewed By: ezgicicek
Differential Revision: D23473145
fbshipit-source-id: 416488176
Summary:
As title.
Facebook
Found this case by examining db.
>
D23394545
Time complexity of `_registerTabPreloadables` has **decreased** from `Top` to `O(1)`. Please make sure this is an expected change. You can inspect the trace to understand the complexity increase:
Reviewed By: ezgicicek
Differential Revision: D23448099
fbshipit-source-id: 108fd1ef2
Summary:
This diff adds translation of `dictionaryWithObjects:forKeys:count:`. In the previous implementation it was
translated as if it was `dictionaryWtihObjectsAndKeys:`, but their function parameters are different.
In this diff, it translates an array literal `NSDictionary* a = @ [ @"firstName": @"Foo", @"lastName":@"Bar" ];` to
```
n$1=NSString.stringWithUTF8:(@"firstName")
n$2=NSNumber.stringWithUTF8:(@"Foo")
n$3=NSNumber.stringWithUTF8:(@"lastName")
n$4=NSNumber.stringWithUTF8:(@"Bar")
temp1[0]:objc_object*=n$1
temp1[1]:objc_object*=n$3
temp2[0]:objc_object*=n$2
temp2[1]:objc_object*=n$4
n$3=NSDictionary.dictionaryWithObjects:forKeys:count:(temp2:objc_object* const [2*8], temp1:objc_object*const [2*8], 2:int)
```
where `temp` is an additional local variable declared as array.
See,
https://developer.apple.com/documentation/foundation/nsdictionary/1574184-dictionarywithobjects?language=objchttps://developer.apple.com/documentation/foundation/nsdictionary/1574181-dictionarywithobjectsandkeys
{F316854542}
Reviewed By: skcho
Differential Revision: D23447042
fbshipit-source-id: 14b7c3f2b
Summary: Added a model for copy constructor for `std::function`. In most cases, the SIL instruction `std::function::function(&dest, &src)` gives us pointers to `dest` and `src`, hence, we model the copy constructor as a shallow copy. However, in some cases, e.g. `std::function f = lambda_literal`, SIL instruction contains the closure itself `std::function::function(&dest, (operator(), captured_vars)`, hence, we need to make sure we copy the right value.
Reviewed By: ezgicicek
Differential Revision: D23396568
fbshipit-source-id: 0acb8f6bc
Summary: We only added suffix-stripped prefixes of props but this causes FPS if a component declares props that actually contain suffixes since we strip them when we are adding builder calls. The fix is to add both normal and stripped versions.
Reviewed By: skcho, Katalune
Differential Revision: D23375405
fbshipit-source-id: e99cb4dd8
Summary:
This diff finishes the migration from the specialization of methods that take blocks as arguments. Here we delete all the old code and change the way we model dispatch functions so that the tests pass.
- Remove the code for specializing the methods in biabduction.
- Remove the call flags `cf_with_block_parameters` that was only used in this algorithm.
- Removes models for dispatch functions.
- Adds models for dispatch functions as program transformation only in biabduction. To be added in other checkers in the future.
Reviewed By: ngorogiannis
Differential Revision: D23345342
fbshipit-source-id: b5e8542ce
Summary:
This preanalysis in general aims to create specialized clones of methods that have blocks as arguments and that are called with concrete closures, and then call these clone methods instead of the original ones.
One complication is what happens with the captured variables in the closure. What we do is we add them to the formals of the cloned method and passed them through to the concrete blocks.
We do this transformation in two steps:
1. Go through all the callers of methods with blocks as parameters, and create the clone methods. In this preanalysis we only create the attributes for the new method, not the code. We also update the call instructions in the callers to represent a call to the cloned method with updated arguments: we don't need to pass closures arguments anymore, we instead pass the captured variables as new arguments.
2. We add the corresponding code to the newly created clones: this means swapping the call to the block variable with a call to the corresponding block. Moreover, we add some of the new formals (that correspond to the captured variables) to the arguments of the call.
This diff implements step 1 of the analysis. The next diff D23216021 implements step 2.
Reviewed By: ngorogiannis
Differential Revision: D23109204
fbshipit-source-id: 91a5eb16b
Summary: There was a mismatch between formals and actuals in `std::function::operator()` because we were not passing the first argument corresponding to the closure.
Reviewed By: ezgicicek
Differential Revision: D23372104
fbshipit-source-id: d0f9b27d6
Summary: When we evaluate lambdas in pulse, we create a closure object with `fake` fields to store captured variables. However, during the function call we were not linking the captured values from the closure object. We address this missing part here.
Reviewed By: jvillard
Differential Revision: D23316750
fbshipit-source-id: 14751aa58
Summary:
Report errors found by running Topl on top of Pulse, when using
--topl-pulse. Topl tests now run on top of Pulse.
Reviewed By: jvillard
Differential Revision: D23030771
fbshipit-source-id: 8770c2902
Summary:
Two issues are fixed
1. For this diff, when the condition `curr_langauge_is Java` is removed in some part of the analysis, some c bufferoverrun tests are broken. This is fixed in this diff by inspecting if we are dealing with a `Size` alias referring to an `objc_internal_collection_array`.
2. Previously, when we are modifying mutable array in a loop, e.g. adding element to the array or removing element from the array, we are unable to give an estimable size of the array after exiting the loop. This is now fixed, and the corresponding FPs are resolved.
Reviewed By: skcho
Differential Revision: D23342350
fbshipit-source-id: 200f5261c
Summary:
The generated code used to contain Prune statements that had boolean
connectives in their conditions. After this commit, all conditions
should have no boolean connective (LNot, LOr, LAnd) at top-level; that
is, prune conditions should be atomic.
The main motivation behind this change is that (a) frontends follow this
convention, and (b) Pulse assumes this convention.
Reviewed By: jvillard
Differential Revision: D23022273
fbshipit-source-id: 1313328e4
Summary:
In the previous diffs, we implement enumerator in order to estimate the cost of for-each loop in ObjC, but when we have FP case when enumerator is used not in for-each loop. For example, the following code has top cost before the fix.
```
void nsarray_enumerator_linear_FP(NSArray* array) {
id obj;
NSInteger sum = 0;
NSEnumerator* enumerator = [array objectEnumerator];
while (obj = [enumerator nextObject]) {
sum += (NSInteger)obj;
}
}
```
Reviewed By: skcho
Differential Revision: D23294895
fbshipit-source-id: 50c7b359f
Summary:
`delete` works exactly like `free` so merge both models together. Also
move the `free(0)` test to nullptr.cpp as it seems more appropriate.
Reviewed By: da319
Differential Revision: D23241297
fbshipit-source-id: 20a32ac54
Summary:
Fix the FP when iterating through constant collection.
facebook
This fix is a hack for now.
Reviewed By: ezgicicek, skcho
Differential Revision: D23241338
fbshipit-source-id: e2e0c05f8
Summary:
As title.
This diff is co-authored by SungKeun Cho and me.
facebook
This diff is co-authored by skcho and me.
Original comments from skcho
"For the record:
1. Rory and I tried to write models for ObjC iterator.
2. We could not use Java's iterator semantics: In Java's, `hasNext` returns the size of collection, rather than a boolean, and which is used as a control variable. On the other hand, in ObjC, it calls only `nextObject`, not calling `hasNext`, and the return value of which is being checked as `null`.
3. We added an artificial field `objc_iterator_offset` to keep the index of the iterator, and the models added in this diff are handling that integer value.
A problem is that `array.objc_iterator_offset` is not included in the control variables, since the condition of the loop is `nextObject() != null` that does not include the iterator offset. We need to make `array.objc_iterator_offset` as a control variable, by changing the part collecting control variables.
"
Reviewed By: ezgicicek, skcho
Differential Revision: D22944278
fbshipit-source-id: 7e71b79c1
Summary: In the frontend captured variables for blocks are added as formal parameters in procdesc at the beginning.
Reviewed By: dulmarod
Differential Revision: D23163619
fbshipit-source-id: 2bcbe9b9c
Summary:
When implementing iterator, we find out that because some semantics of inferbo is Java-specific, we cannot simply use Java's `Collection` model for `NSCollection`.
So this diff writing `NSCollection` model separately.
This diff also extracts the common parts of `NSCollection` and `Collection` into `AbstractCollection` to combine the duplicate the parts.
Reviewed By: ezgicicek
Differential Revision: D22975159
fbshipit-source-id: daed3f99f
Summary:
We already take into account inheritance if the method inherits a known
modelled initializer method (e.g. Activity.onCreate()).
But if the method is explicitly marked as Initializer, we require its
overrides to be also marked.
This diffs fixes the behavior and makes it consistent, now this is
enough to annotate only parent class.
Reviewed By: jvillard
Differential Revision: D23135177
fbshipit-source-id: a21ff4a0e
Summary: Before we were modelling `vector.end()` as returning a fresh pointer every time is was called. It is common to check if an iterator is not the `end()` iterator and proceed to dereference the iterator in that case. In such code pattern `vector.end()` is called twice and returns different fresh values which causes false positives. To fix this, we add a special internal field `__infer_model_backing_array_pointer_to_last_element` to a vector to denote its end. Now, every time we call `vector.end()` we return the value of this field. We introduce a new attribute `EndOfCollection` to mark `end` iterator as the existing `EndIterator` invalidation is not suitable when we need to read the same value multiple times.
Reviewed By: jvillard
Differential Revision: D23101185
fbshipit-source-id: fa8a33b58
Summary:
This time it's personal.
Roll out pulse's own arithmetic domain to be fast and be able to add
precision as needed. Formulas are precise representations of the path
condition to allow for good inter-procedural precision. Reasoning on
these is somewhat ad-hoc (except for equalities, but even these aren't
quite properly saturated in general), so expect lots of holes.
Skipping dead code in the interest of readability as this (at least
temporarily) doesn't use pudge anymore. This may make a come-back as
pudge has/will have better precision: the proposed implementation of
`PulseFormula` is very cheap so can be used any time we could want to
prune paths (see following commits), but this comes at the price of some
precision. Calling into pudge at reporting time still sounds like a good
idea to reduce false positives due to infeasible paths.
#skipdeadcode
Reviewed By: skcho
Differential Revision: D22576004
fbshipit-source-id: c91793256
Summary:
Current handling of lambdas is quite rudimentary. Looking at test
results we can see that errors are all over the place: False Positives,
False Negatives and just plain wrong results.
These tests can be grouped in 2 sets:
1. Basic support which implies:
- understanding method signatures,
- providing comprehensible error messages.
2. Extended support with implies:
- understanding scoping of values captures in lambdas (needs proper aliasing analysis).
- understanding parametric nullability in generics (needs "some"
support for Generics in our Java frontend).
With follow-up patches I'll attempt to implement "Basic" support for
Lambdas. "Extended" support will be out of scope unless there's
significant demand.
Reviewed By: mityal
Differential Revision: D23058673
fbshipit-source-id: 621551cca
Summary:
This diff adds a false positive test that is introduced imprecise loop
invariant detection.
In the example, `i` and a temp variable `$irvar = get_size(arr)` are
all included in the control variables, so the complexity becomes
quadratic. The problem is that `$irvar` is not addressed as a loop
invariant:
* `is.read` is analyzed as modifying a global
* all return variables, including `$irvar`, of unmodeled functions are invalidated
Reviewed By: ezgicicek
Differential Revision: D23051414
fbshipit-source-id: 011fd086b
Summary: To avoid dead store false positives we skip initialization of a variable that has an `unused` attribute. However, this causes uninitialized value false positives when the variable is later used in macros. To fix this, instead of skipping initialization we record the information about `unused` attribute in local variable data that we can later use for filtering out dead store issues.
Reviewed By: jvillard
Differential Revision: D22868050
fbshipit-source-id: 4a2d0e680
Summary:
We get duplicated variable declaration instruction for primitive type variable initialized using list initializer, e.g.
```
int* p{nullptr};
```
This happens because we add variable declaration instruction when we translate both `DeclStmt` and `InitListExpr`. To fix this, we do not add the duplicated variable declaration when we translate `InitListExpr`.
Reviewed By: jvillard
Differential Revision: D22844726
fbshipit-source-id: 422806924
Summary:
Synthetic/autogenerated methods/fields usually contain `$` in their names.
Reporting nullability violations on such code doesn't make much sense
since the violations are not actionable for users and likely need to be
resolved on another level.
This diff contributes:
1. Several test cases that involve synthetic code of different
complexity.
2. Code that handles some particular types of errors (but not all!).
Reviewed By: mityal
Differential Revision: D22984578
fbshipit-source-id: d25806209
Summary:
`java_type` aka `JavaSplitName.t` is a pair of strings. It's used in a procname to store the return type. Replace that with `Typ.t`.
This is step one of deleting `JavaSplitName`. Step two will be to replace parameters with `Typ.t`.
Reviewed By: skcho
Differential Revision: D20323748
fbshipit-source-id: f0029c3ca
Summary:
This diff removes a dead field `Struct.subs`, which was used in
heuristics finding methods from sub-classes.
Reviewed By: ezgicicek
Differential Revision: D22945346
fbshipit-source-id: 4b3bf0093
Summary: Before, `NSCollection` are modelled like array, but this will have issue when we want to say add object to array. This diff changes `NSCollection`'s model to use Java's Collection model.
Reviewed By: ezgicicek
Differential Revision: D22840079
fbshipit-source-id: b944b743b
Summary:
In Cost/Inferbo checkers, it tried to find a subclass with heuristics when a method of interface or
abstract class is called. While it makes preciser analysis results in general, sometimes introduced
tricky FPs since the behavior of the heuristics depends on targets. This diff revert the heuristics
to suppress the FPs.
Reviewed By: ngorogiannis
Differential Revision: D22924485
fbshipit-source-id: 9f151231f
Summary: Implement `alloc` and implement initialisation method that uses the return value of `alloc`, i.e. `NSString.init`.
Reviewed By: ezgicicek
Differential Revision: D22840080
fbshipit-source-id: 47a7523e3
Summary:
This diff translates for-in block in objc as a simple for-loop. For example,
`for (item_type item in items) { body }` is translated to
```
NSEnumerator *enumerator = [items objectEnumerator];
item_type item;
while (item = [enumerator nextObject]) { body }
```
Reviewed By: ezgicicek
Differential Revision: D22841524
fbshipit-source-id: 296ee84df
Summary:
There are two ways to suppress it.
1. Field level suppression annotation (was already tested). This will
apply to all constructors.
2. Constructor level annotation (this is what this test does). Sometimes
there are "fake" constructors that are not intended to be called in
prod, they might leave some fields not initialized.
Note that there are two ways to add a suppression; one has a known
problem that is documented here.
Reviewed By: artempyanykh
Differential Revision: D22864869
fbshipit-source-id: f95aaa26a
Summary:
When expressions use generics or typecasts, CFG contains intermediate `_fun_cast` nodes which break some nullsafe heuristics and lead to false positives.
This affects different types of checks (null-check on assignment expressions, `map.containsKey` checks in assignment expressions, regular typecasts, etc.
See added tests for examples.
Reviewed By: mityal
Differential Revision: D22815631
fbshipit-source-id: 80d444b1c
Summary:
We check for supertypes in Java. Why not ObjC?
Would be good to get dulmarod's input here.
Reviewed By: roro47
Differential Revision: D22817126
fbshipit-source-id: 52c1c3f3c
Summary:
The old --topl-only is now --topl-biabd-only, and there's also
--topl-pulse-only. This is WIP: the latter runs pulse, but it doesn't yet
extract Topl errors from pulse summaries. (The citv part of pulse path
conditions appears to have the necessary information.)
Reviewed By: jvillard
Differential Revision: D22815250
fbshipit-source-id: a01792945
Summary:
This diff:
1. Adds general capability to model any field as nullable /
non-nullable.
2. Uses it for Boolean.TRUE and Boolean.FALSE
Reviewed By: artempyanykh
Differential Revision: D22794226
fbshipit-source-id: 95f586592
Summary: D17500386 had added the ability to give symbolic values on functions returning exceptions. However, this might cause FPs or cryptic complexity reports (especially with subclass heuristics). This diff aims to revert it back.
Reviewed By: skcho
Differential Revision: D22764266
fbshipit-source-id: 1615544d8
Summary: We model internal builtin `__new` function to return a non-null value. This fixes nullptr_dereference false positives where we explicitly check the result of a function call for nullptr when the function returns a newly created object.
Reviewed By: jvillard
Differential Revision: D22772217
fbshipit-source-id: 37d209697
Summary:
The java frontend used an unsound flow insensitive class analysis to devirtualize
some virtual calls. We remove it and let the recent devirtualizer preanalysis do the job.
This unsoudness in the Java frontend may have been here for a long time. Removing it may
modify several analysis results (specially Nullsafe) where virtual calls may look different
now.
Reviewed By: jvillard
Differential Revision: D22662739
fbshipit-source-id: c45296dce
Jules Villard
Mitya Lyubarskiy
Daiva Naudziuniene
Sungkeun Cho
Nikos Gorogiannis
Artem Pianykh
Ezgi Çiçek
Martin Trojer
Qianyi Shu
Dulma Churchill
Radu Grigore
David Pichardie