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: 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: 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:
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:
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:
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:
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: 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: 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: 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:
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:
This diff adds translation of `arrayWithObjects:count:`. In the previous implementation it was
translated as if it was `arrayWithObjects:`, but their function parameters are different.
In this diff, it translates an array literal `NSArray* a = @ [ 2, 3 ];` to
```
n$1=NSNumber.numberWithInt:(2:int)
n$2=NSNumber.numberWithInt:(3:int)
temp[0]:objc_object*=n$1
temp[1]:objc_object*=n$2
n$3=NSArray.arrayWithObjects:count:(temp:objc_object* const [2*8],2:int)
a:NSArray*=n$3
```
where `temp` is an additional local variable declared as array.
See,
https://developer.apple.com/documentation/foundation/nsarray/1460145-arraywithobjectshttps://developer.apple.com/documentation/foundation/nsarray/1460096-arraywithobjects?language=objc
Reviewed By: jvillard
Differential Revision: D22631305
fbshipit-source-id: 5be0a55d4
Summary:
This will allow all the analyses to be able to call closures without any special treatment: we transform the call to variables that point to closures into normal function calls. We treat only ObjC blocks at the moment, with C++ lambdas to be done as a next step.
We aimed to achieve certain results in Pulse (see tests: avoid memory leaks and NPEs FPs) while also keeping the biabduction analysis working as before.
We also checked that for the examples analyzed Pulse behaves like the correct semantics of ObjC programs with blocks.
Reviewed By: jvillard
Differential Revision: D22547333
fbshipit-source-id: efe56ed51
Summary: Add cost model for most common `NSString` functions in cost analysis
Reviewed By: skcho
Differential Revision: D22433005
fbshipit-source-id: 2f57bbda9
Summary: If a node is unreachable and the cost of the node is Top, we were giving Top cost :( Let's fix it.
Reviewed By: skcho
Differential Revision: D22548269
fbshipit-source-id: d79743669
Summary:
We update the type of captured variables to include information about capture mode (`ByReference` or `ByValue`) both for procdesc attributes and the closure expression.
For lambda: closure expression now contains correct capture mode for capture variables. Procdesc still does not contain information about captured variables which we will address in the next diff.
For objc blocks: at the moment all captured variables have mode `ByReference`. Added TODOs to fix this.
Reviewed By: jvillard
Differential Revision: D22572054
fbshipit-source-id: 4c88678ee
Summary:
As title
Model `NSString` as `JavaString`.
Since `NSArray` does not contain information about its type of element, we do not use associate string with collection as in Java and C++. In Java, String model is implemented using java collection, and for C++, string model is implemented using vector.
So instead, we use existing `JavaString` model.
Reviewed By: skcho
Differential Revision: D22431949
fbshipit-source-id: 7cdde1ad7
Summary: This diff prevents printing line numbers of loop in the trace description, which helps to keep the same descriptions even when the line number of a function is changed in tests.
Reviewed By: ezgicicek
Differential Revision: D22375584
fbshipit-source-id: 676d1a7cc