Summary:
As explained in the previous diff: when the access trace goes through
the invalidation step there is no need to print the invalidation trace
at all.
Note: only a few sources of invalidation are handled at the moment. The
following diffs gradually fix the other sources of invalidation.
Reviewed By: skcho
Differential Revision: D28098335
fbshipit-source-id: 5a5e6481e
Summary:
The eventual goal is to stop having separate sections of the trace
("invalidation part" + "access part") when the "access part" already
goes through the invalidation step. For this, it needs to record when a
value is made invalid along the path.
This is also important for assignements to NULL/0/nullptr/nil: right now
the way we record that 0 is not a valid address is via an attribute
attached to the abstract value that corresponds to 0. This makes traces
inconsistent sometimes: 0 can appear in many places in the same function
and we won't necessarily pick the correct one. In other words, attaching
traces to *values* is fragile, as the same value can be produced in many
ways. On the other hand, histories are stored at the point of access, eg
x->f, so have a much better chance of being correct. See added test:
right now its traces is completely wrong and makes the 0 in `if
(utf16StringLen == 0)` the source of the NULL value instead of the
return of `malloc()`!
This diff makes the traces slightly more verbose for now but this is
fixed in a following diff as the traces that got longer are those that
don't actually need an "invalidation" trace.
Reviewed By: skcho
Differential Revision: D28098337
fbshipit-source-id: e17929259
Summary:
See added test: pulse sometimes insisted that an issue was latent even
though the condition that made it latent could not be influenced (hence
could the issue could never become manifest) by callers because it was
unrelated to the pre, i.e. it came from a mutation inside the function.
In these cases, we want to report the issue straight away instead of
keeping it latent.
Reviewed By: skcho
Differential Revision: D28002725
fbshipit-source-id: ce9e6f190
Summary:
This diff adds semantics for temporary boolean variables to keep config values.
* It extended value domain to have `TempBool` that is basically a pair of `ConfigChecks.t`; one is a
set of config values checked when the temporary variable is true, and the other is that when the
temporary variable is false.
* It assigns the `TempBool` value when `temp=1` or `temp=0`.
* It uses the `TempBool` value when pruning condition expression.
For example, when there is an `if` statement of
```
return (config && b);
```
it is translated in SIL,
```
if (config) {
if (b) {
temp = 1; // (1)
} else {
temp = 0; // (2)
}
} else {
temp = 0; // (3)
}
return temp;
```
then we can say
* When `temp` is true, i.e. at (1), it is gated by `config`
* When `temp` is false, i.e. at (2) and (3), we are not sure about the the gatedness; at (2) it is gated by `config` but at (3) it is gated by `!config`.
So, we record such information as a `TempBool.t` value.
Next, when we use the return value at its caller,
```
if (ret) {
// then branch
} else {
// else branch
}
```
We can say "then branch" part is gated by `config`, but we are not sure if "else branch" part is gated, by using the `TempBool.t` value of `ret`.
Reviewed By: ezgicicek
Differential Revision: D28056490
fbshipit-source-id: e90d8afd3
Summary: Small refactor as this function belongs more in Pvar than Var.
Reviewed By: skcho
Differential Revision: D28091618
fbshipit-source-id: 259bd82d5
Summary: To be fair that doesn't seem to matter at all, with no test affected.
Reviewed By: ngorogiannis
Differential Revision: D28091608
fbshipit-source-id: 172bd2ff1
Summary:
Just moving stuff around.
This is possibly useful for making Pvar depend on ProcAttributes for
other things, eg checking if a pvar is captured by a procedure (which
would be awkward to have in the API of ProcAttributes and not Pvar).
Overall it forced me to move a few other things around in a way that I
feel makes more sense anyway.
Reviewed By: skcho
Differential Revision: D28091497
fbshipit-source-id: 367a1f17c
Summary:
Before returning a summary, restore formals to their initial values.
This gets rid of a false latent because the value in the path condition
is now garbage-collected.
Added a test for the tricky case of structs passed as values.
Reviewed By: skcho
Differential Revision: D28001229
fbshipit-source-id: 23dda5b43
Summary:
This diff adds semantics for long-typed config values.
* It extended branch types to keep condition expressions passed,
* then used it to in the prune semantics.
Reviewed By: ezgicicek
Differential Revision: D28055936
fbshipit-source-id: 0d12930cf
Summary:
This diff introduces [ISys.file_exists] that is similar to [Sys.file_exists_exn], but returns
[false] when the result is known, instead of raising an exception.
Reviewed By: jvillard
Differential Revision: D28059863
fbshipit-source-id: d54851cfb
Summary: This diff adds an abstract semantics for returning config values at function calls.
Reviewed By: ezgicicek
Differential Revision: D28055544
fbshipit-source-id: 5fe51c538
Summary:
This looks a bit better as it makes it easier to ignore parts of the
arguments in models, which happens all the time. Also easier to add more
to the record in the future, which is the real reason.
Reviewed By: skcho
Differential Revision: D27997695
fbshipit-source-id: a7c680025
Summary:
This diff avoids dereference of C struct, in its frontend and its semantics of Pulse. In SIL, C
struct is not first-class value, thus dereferencing on it does not make sense.
Reviewed By: ezgicicek
Differential Revision: D27953258
fbshipit-source-id: 348d56338
Summary: This diff copies each field values inside setter/getter of ObjC.
Reviewed By: ezgicicek
Differential Revision: D27940521
fbshipit-source-id: 9977cae75
Summary:
This diff does refactoring for the following diff.
* Define Mangled.return_param and Mangled.is_return_param and use it instead of
Ident.name_return_param.
* Share common code from objc_setter and objc_getter
* Move struct_copy to CStructUtils.ml
Reviewed By: da319
Differential Revision: D27940125
fbshipit-source-id: 84eb3109b
Summary:
Looking at the recent silent analysis results, it seems that we report many direct unknown library calls (often cheap)... However, if these were called inside some other callee we wouldn't report them because their costs would be assumed to be constant by the cost analysis.
This is a bit awkward. We should either report all unknown calls or suppress them altogether.
Since we have too many reports per day and not a good way to determine whether an unknown library call is cheap/expensive, let's take option 2.
Then, we would be only relying on two things to determine whether to report/not:
- instantiated cost's degree > 1
- explicitly known to be expensive (i.e. modeled in ConfigImpact, like string append)
Reviewed By: skcho
Differential Revision: D27909003
fbshipit-source-id: 0391d226d
Summary:
This is mostly useful to avoid duplicating error states, which are
propagated unchanged through both branches of, say, conditionals, and
can end up duplicated if the join is not careful:
```
{[Abort(Error 1), Abort(Error 2), Continue σ']}
if (..) { .. } else { .. }
{JOIN([Abort(Error 1), Abort(Error 2), Continue σ_then],
[Abort(Error 1), Abort(Error 2), Continue σ_else])}
{[Abort(Error 1), Abort(Error 2), Continue σ_then, Continue σ_else]}
```
Whereas before this diff we got
```
{[Abort(Error 1), Abort(Error 2), Continue σ_then, Abort(Error 1), Abort(Error 2), Continue σ_else]}
```
Detect states that do not change simply using `phys_equal` as they
should literally not change. Refactor the code to be able to re-use the
same logic in the stronger join used in widening, that compares states
using the domain's `leq` relation to establish implication.
Reviewed By: ezgicicek
Differential Revision: D27908529
fbshipit-source-id: b461165da
Summary:
When a block value is passed via more than one-depth of function calls, it is not analyzed correctly
because current inlining mechanism (specializing objc block parameters) of the frontend works for
only one-depth of block passing. This diff gives up analyzing initialized-ness of captured
variables in ObjC to avoid FPs.
Reviewed By: da319
Differential Revision: D27885395
fbshipit-source-id: fc6b4663c
Summary: We have some FPs due to unknown init methods that are added dynamically.
Reviewed By: ezgicicek
Differential Revision: D27856371
fbshipit-source-id: b6fb46df3
Summary:
This diff filters known expensive callees when cost is constant.
previous:
```
foo() {
known_expensive_call();
}
```
current:
```
foo() {
known_expensive_call();
goo();
}
// cost is constant
goo() {
known_expensive_call();
unknown_call();
}
```
When callee's cost is constant and its summary includes known expensive callees, the checker addressed it as a non-constant-cost callee, i.e., it copies all ungated callees from the callee's summary. However, sometimes this full-copying introduces unexpected issues. For example, suppose a callee `goo` is added and `goo`'s cost is constant as above. Since it includes `known_expensive_call`, all ungated callees of its summary is copied to the caller `foo`'s summary:
* `foo`'s ungated callees (before): {`known_expensive_call`}
* `foo`'s ungated callees (after): {`known_expensive_call`, `unknown_call`}
As a result, it would report about `unknown_call` is added. However, this is not what we intended: In the example, `unknown_call` is reported because it is called in the same function with `known_expensive_call`, not because it is expensive.
To fix that issue, this diff filters known expensive callees from `goo`'s summary in that case.
Reviewed By: ezgicicek
Differential Revision: D27852552
fbshipit-source-id: d207eef1c
Summary:
It introduced a FP due to reporting addition of `__cast`.
* This diff added known cheap model for `__cast`.
* In addition, moved `match_builtin` to `BuiltinDecl`.
Reviewed By: ezgicicek
Differential Revision: D27791495
fbshipit-source-id: 55aec1728
Summary:
Previously we were only taking constexpr into account on constructors.
Add this info to ProcAttributes.t instead by exporting it from the
plugin for all functions.
This allows SIOF to take constexpr into account in more cases as it's not
always good at capturing which functions *can* be constexpr-evaluated,
which caused false positives.
Delete now-useless is_constexpr in constructor types. This generated the
changes in frontend tests.
Some minor renamings of variants of is_const_expr -> is_constexpr.
Reviewed By: da319
Differential Revision: D27503433
fbshipit-source-id: 3d1972900
Summary:
When a field is assigned by a value,
```
_.field = exp;
```
it should collect the field when the abstract config value of `exp` is non-bottom, rather than
non-top.
Reviewed By: ezgicicek
Differential Revision: D27766188
fbshipit-source-id: a0b1f2c28
Summary: Added a new issue type for sending a message to nil when its return type is non-POD. To distinguish these issues from other nullptr dereference issues, we extend the `MustBeValid` attribute to contain the reason of why an address must be valid. For now a reason can only have `SelfOfNonPODReturnMethod` as it's value, but in the future we will use it for other nullability issue types, such as nil insertion into collections.
Reviewed By: jvillard
Differential Revision: D27762333
fbshipit-source-id: 689e5a431
Summary:
In order to use Inferbo's analysis result, a checker should know current instruction index.
However, for the checkers using `ProcCfg.Normal` CFG, it was impossible to get the instruction
index. To solve the issue, this diff changes the AbsInt framework to give the index together to
`exec_instr`.
Reviewed By: ezgicicek
Differential Revision: D27680894
fbshipit-source-id: 1dc8ff0fb
Summary:
The problem is that `Models.is_field_nonnullable` didn't differentiate
between
- having a nullable model (in which case we want the field to be NULLABLE),
- not having a model at all (in which case we want the field to be THIRDPARTY_NONNULL).
The problem was noticed only now because previously we didn't have any
NULLABLE field models.
Reviewed By: ngorogiannis
Differential Revision: D27709508
fbshipit-source-id: b98c8f86f
Summary:
This diff evaluates a cpp vector given as a parameter symbolically. Especially, it addresses it as an array, so the cost checker can use its symbolic length correctly.
**About handling `cpp.vector_elem` field:**
The field is a virtual field of vector object that points to the array of vector elements. It was introduced in Inferbo to model semantics of vector operations.
Since many semantics of Inferbo depends on type information, it had collected type information of vector elements, whenever `cpp.vector_elem` field was introduced, as a *side-effect*. A problem is that it has *side-effect*, which means it may introduce non-deterministic analysis results depending on the type information of the virtual field.
This diff changes it not to collect the type information on `cpp.vector_elem` as a side-effect. Instead, it tries to write the information to the abstract states (abstract location) when possible.
Reviewed By: ezgicicek
Differential Revision: D27674935
fbshipit-source-id: f3d52cae7
Summary:
In D27430485 (a6ab4d38cf), we used the static cost of the callee to determine whether it was cheap/expensive. This diff improves on that by taking the whole instantiated cost of the function call (not just the callee's cost).
Also, if the callee is an unmodeled call, we consider it to be expensive as before.
Note: cost instantiation was used by hoisting. I refactored bunch of code there to reuse as much as code possible.
Reviewed By: skcho
Differential Revision: D27649302
fbshipit-source-id: 07d11f3dd
Summary: When instantiating the callee's cost, we have picked up the InferBo memory at the node corresponding to the last instruction. Instead, we should pick up right at the call instruction. Picking it up later might cause arguments to go out of scope.
Reviewed By: skcho
Differential Revision: D27652474
fbshipit-source-id: 5ab35cabb
Summary:
The output differs on Java 11 compared to Java 8: one prints an
interface, the other resolves to a class name.
Reviewed By: ezgicicek
Differential Revision: D27678552
fbshipit-source-id: c5a5d0c39
Summary: We have been referring to the arguments of a function call as "params". This has been bothering me. Let's fix it!
Reviewed By: ngorogiannis
Differential Revision: D27649158
fbshipit-source-id: 10e0b28cb
Summary:
To avoid too big abstract states due to instantiated templates in C++,
this diff loosens the compare functions of field names and ungated
callees.
Reviewed By: ezgicicek
Differential Revision: D27625775
fbshipit-source-id: e33e9d34c
Summary:
Nullsafe/biabduction tests were sensitive to Java version: they were recorded for Java 8 but if the machine that is used to run the tests had Java 11, tests would fail. This diff aims to resolve this issue by
- making our tests produce java8-compatible bytecode so that tests don't fail on Java 11 machines
- removing nullsafe tests that exercise obscure Java 8 behavior that cannot be alleviated with backward compatible bytecode on Java 11
- changing lambda argument printing to be Java 11 compatible
Reviewed By: martintrojer
Differential Revision: D27500731
fbshipit-source-id: 77fe302ea
Summary:
Reporting all ungated (un configed?) function calls causes many FPs. Instead, we rely on complexity analysis to determine whether a function is cheap/expensive: if the callee's complexity is not symbolic (e.g. constant), we consider it as cheap and don't keep track of it.
Note that we don't take the instantiated/modeled cost into account yet. So, if we have `foo(int n)` with complexity `O(n)`, and call it as `foo(3)`, we would still keep track of it. Similarly, if `foo` is a modeled function with constant time complexity, we would have no summary for it hence would keep track of it.
These will be improved later.
Reviewed By: skcho
Differential Revision: D27430485
fbshipit-source-id: d5f66320d
Summary:
This diff removes additional inferbo options `--bufferoverrun` from cost tests, since printing
inferbo issues is not that useful to understand cost results.
Reviewed By: ngorogiannis
Differential Revision: D27592496
fbshipit-source-id: 6ab3e6528
Summary:
Whenever an equality "t = v" (t an arbitrary term, v a variable) is
added (or "v = t"), remember the "t -> v" mapping after canonicalising t
and v. Use this to detect when two variables are equal to the same term:
`t = v` and `t = v'` now yields `v = v'` to be added to the equality
relation of variables. This increases the precision of the arithmetic
engine.
Interestingly, the impact on most code I've tried is:
1. mostly same perfs as before, if a bit slower (could be within noise)
2. slightly more (latent) bugs reported in absolute numbers
I would have expected it to be more expensive and yield fewer bugs (as
fewer false positives), but there could be second-order effects at play
here where we get more coverage. We definitely get more latent issues
due to dereferencing pointers after testing nullness, as can be seen in
the unit tests as well, which may alone explain (2).
There's some complexity when adding term equalities where the term
is linear, as we also need to add it to `linear_eqs` but `term_eqs` and
`linear_eqs` are interested in slightly different normal forms.
Reviewed By: skcho
Differential Revision: D27331336
fbshipit-source-id: 7314e127a
Summary:
It's better (=possibly more efficient) to take the opportunity to
normalize linear terms when we can instead of possibly having to apply
the same normalization over and over on individual terms until the next
round of proper normalization.
Reviewed By: skcho
Differential Revision: D27464885
fbshipit-source-id: 0dc01a089
Summary:
When we don't know the value being shifted it may help to translate
bit-shifting into multiplication by a constant as it might surface
linear terms, eg `x<<1` is `2*x`.
Reviewed By: skcho
Differential Revision: D27464847
fbshipit-source-id: 9b3b5f0d0
Summary:
The simplifications done by `simplify_shallow` are all taken care of by
`eval_const_shallow` as well, they just also happen to help when not
*all* of the term is a constant. However, they might be less
precise/efficient than in the constant case, in particular in the next
diff that translates `x << c` into `x * 2^c` when `c` is constant.
Reviewed By: skcho
Differential Revision: D27464805
fbshipit-source-id: 452bc6ab1
Summary:
On some pathological examples of crypto primitives like libsodium, later
diffs make pulse grind to a halt due to an explosion in the size of
literals. This is at least partly due to the fact the arithmetic doesn't
operate modulo 2^64.
Due to the fact the arithmetic is confused in any case when we reach
such large numbers, cap them, currently at 2^128. This removes pathological
cases for now, even now on libsodium Pulse is ~5 times faster than before!
Take this opportunity to put the modified Q/Z modules in the own files.
Reviewed By: jberdine
Differential Revision: D27463933
fbshipit-source-id: 342d941e2
Summary: Just some scaffolding to save a bit of churn from the next diff.
Reviewed By: skcho
Differential Revision: D27328348
fbshipit-source-id: 4f5bfcc65
Summary:
This was added in C++14. Was investigating how SIOF dealt with this but
it turns out it already does the right thing as the translation unit of
global variable templates shows up as the place they are instantiated
(not the one where they are declared), which works well for SIOF
checking.
Reviewed By: da319
Differential Revision: D27500998
fbshipit-source-id: b8b9b9c48
Summary:
This is better suited than the generic "cGeneral_utils", and saves
exporting one of them too.
Reviewed By: da319
Differential Revision: D27500933
fbshipit-source-id: f4224f63b
Summary: One source of non-deterministic diff result is when there are multiple overloaded methods the cardinals of unchecked callees of which are the same. This diff tries to select one of them in a more deterministic manner.
Reviewed By: ezgicicek, ngorogiannis
Differential Revision: D27430757
fbshipit-source-id: 38ba5d8dc
Summary: Error message was accidentally changed to a specific nullptr error message (D26887140 (cba144b779)) for any invalidation (use after delete, etc). This diff reverts back the error message for a general case and keeps the special case for nullptr dereference. Also fixed spacing for nullptr dereference error message.
Reviewed By: jvillard
Differential Revision: D27407628
fbshipit-source-id: 2649f3032
Summary:
The title
Also notice that there is a duplication of an error.
Reviewed By: skcho
Differential Revision: D27426933
fbshipit-source-id: dbd2f861a
Summary: Autogenerated methods sometimes lead to false positives. Also, clean up a little the models file.
Reviewed By: da319
Differential Revision: D27393933
fbshipit-source-id: f79b1a6eb
Summary: To support objc nil messaging for unknown function calls we prune `self` to be positive in the `normal` specification and add additional specification to handle nil case.
Reviewed By: skcho
Differential Revision: D27360757
fbshipit-source-id: 119999b30
Summary:
This addresses a test difference between java versions. Infer's java tests are recorded with Java8 where string concat with a constant string uses `toString`. However, if tests are run on a machine where Java 11 is used, string concat is done via `makeConcatWithConstants` which causes tests to fail.
As a workaround, we replace the test so that Java version dependent string concat is not used.
Reviewed By: ngorogiannis
Differential Revision: D27394621
fbshipit-source-id: dfe1af2ac
Summary:
Fixing `IsInstanceOf` term simplification for null case. Before, this
was only being done if value was known to be null at the moment of the
call to `instanceof`. Otherwise, the `IsInstanceOf` term would remain in
the formula unnecessarily.
Reviewed By: jvillard
Differential Revision: D27361025
fbshipit-source-id: 2d958a757
Summary:
Models for Java Map interface.
This consists of `Map.init()`, `Map.put(key, value)`, `Map.get(key)`,
`Map.containsKey(key)` and
`Map.isEmpty()`. With the exception of `Map.get(key)` and `Map.containsKey(key)`, these functions were modelled using the respective similar ones provided by the Java Collection interface.
Reviewed By: jvillard
Differential Revision: D27326716
fbshipit-source-id: e07f0c952
Summary:
This diff add semantics for collecting all object fields that may have config values. The collected information is used to instantiate conditional unchecked callees introduced in the previous diff.
How it works:
* The summary is extended to have `config_fields:Fields.t`. It has all fields that may have config values intra-procedurally.
* Before reporting to `config-impact-report.json`, it unions all `config_fields` from all specs.
* Using `all_config_fields`, it instantiates each summaries and writes results to `config-impact-report.json`.
Reviewed By: ezgicicek
Differential Revision: D27326306
fbshipit-source-id: 42f16ca45
Summary:
This diff extends domain and semantics to understand object fields that may have config values.
Now, `Summary.t` has one more field `unchecked_callees_conditional`, which is a map from a set of object fields to a set of callees. The meaning is that the callees are called depending of the fields, ie
* if one of field of the fields is known to be an actual config value, the callees are safely gated,
* otherwise, the callees are ungated.
For example,
```
void foo() {
if (mField1) {
if (mField2) {
callee1();
}
callee2();
}
}
```
`foo` will have `unchecked_callees_conditional` value of
```
{ {mField1,mField2} -> {callee1},
{mField1} -> {callee2} }
```
Later, if we know that `mField2` has a config value, we can say `callee1` is gated, or if we know that `mField1` has a config value, we can say `callee1` and `callee2` are gated.
The following diff will add an analysis that collects object fields that may have config values.
Reviewed By: ezgicicek
Differential Revision: D27325522
fbshipit-source-id: d4aff58cb
Summary:
Copied the documentation from a document created by rgrig
(thanks!!).
Reviewed By: rgrig
Differential Revision: D27325829
fbshipit-source-id: 118e1a2be
Summary:
The explicit marker for nondeterministic states was used to speed up the
shallow implementations of Topl, which ar enow removed.
Reviewed By: jvillard
Differential Revision: D27297019
fbshipit-source-id: 0fce93817
Summary:
refactoring Java Integer model so that it uses the new
API designed for manipulating fields in Java.
Reviewed By: jvillard
Differential Revision: D27231810
fbshipit-source-id: 0d9e3c951
Summary:
## Issue:
On `master`, it seems that there is a missing newline when Infer prints the `tenv` for a structure type:
```bash
avj@platypus /tmp/infer_bug$ cat test.c
typedef struct {
int a;
} st1;
typedef struct {
int b;
} st2;
avj@platypus /tmp/infer_bug$ infer --version
Infer version v1.0.0-55871dd28
Copyright 2009 - present Facebook. All Rights Reserved.
avj@platypus /tmp/infer_bug$ rm -rf infer-out && infer --debug run -P -- gcc -c test.c
Logs in /tmp/infer_bug/infer-out/logs
Capturing in make/cc mode...
Found 1 source file to analyze in /tmp/infer_bug/infer-out
No issues found
avj@platypus /tmp/infer_bug$ grep -A1 "dummy" infer-out/captured/*/*.tenv.debug
dummy: falsestruct st1
fields: {
--
dummy: falsestruct st2
fields: {
--
dummy: falsestruct objc_class
fields: {}
```
(notice that `dummy: false` and `struct objc_class` are on the same line, with no spacing)
## Resolution
Their PR adds an explicit newline at the end of pretty-printing a structured value, such that it is formatted correctly in the `tenv`:
```bash
avj@platypus /tmp/infer_bug$ infer --version
Infer version v1.1.0-bb5a33506
Copyright 2009 - present Facebook. All Rights Reserved.
avj@platypus /tmp/infer_bug$ rm -rf infer-out && infer --debug run -P -- gcc -c test.c
Logs in /tmp/infer_bug/infer-out/logs
Capturing in make/cc mode...
Found 1 source file to analyze in /tmp/infer_bug/infer-out
No issues found
avj@platypus /tmp/infer_bug$ grep -A1 "dummy" infer-out/captured/*/*.tenv.debug
dummy: false
struct st1
--
dummy: false
struct st2
--
dummy: false
struct objc_class
--
dummy: false
```
(*edit*: I forgot to build after committing; now with updated hash)
Signed-off-by: Andrew V. Jones <andrewvaughanj@gmail.com>
Pull Request resolved: https://github.com/facebook/infer/pull/1416
Reviewed By: skcho
Differential Revision: D27264518
Pulled By: jvillard
fbshipit-source-id: 3b86b4c22
Summary:
Before this diff, TOPL had 3 implementations:
1. a post-processing of biabduction summaries
2. a post-processing of pulse summaries
3. a deep embedding in pulse
1 and 2 additionally require instrumenting SIL to generate monitors for
the TOPL properties. 3 is faster than both 1 and 2, by a good lot, and
doesn't require instrumenting the SIL code. Thus, delete 1 and 2!
Also harmonise the CLI so that TOPL is activated by --topl, which
actives it as a checker, like other analyses.
Reviewed By: rgrig
Differential Revision: D27270178
fbshipit-source-id: e86cf972b
Summary:
Changing model for Java `Collection` interface. Every collection has now two internal fields, initially set to `null`. We also keep an extra field to compute emptiness. This model was implemented based on the [preexisting model for HashMap](https://github.com/facebook/infer/blob/master/infer/models/java/src/java/util/HashMap.java).
Existing models (`add`, `remove`, `set` and `is_empty`) have been updated accordingly and new models are provided: `init` and `clear`.
This model is not yet compatible with the `Map` interface but this change will happen very soon.
Reviewed By: ezgicicek
Differential Revision: D27126815
fbshipit-source-id: 79a5fe306
Summary: This diff ignores java.lang.Math method calls since they are all cheap.
Reviewed By: ezgicicek
Differential Revision: D27267282
fbshipit-source-id: ad0a4ef4f
Summary:
There could still be divisions by zero, eg in the "mod" case: consider
"x mod (1/2)" (doesn't matter what x is). Then we'd check "1/2 =? 0" and
since it's false conclude that it's safe to take the modulo... oops!
To make things safer, harden `Z` to not throw anymore.
Also add a layer of defense in depth by wrapping the functions that do
Z/Q operations in another layer of exception catching because we really
don't want to crash the entire analysis due to that.
Reviewed By: martintrojer
Differential Revision: D27262569
fbshipit-source-id: e22187ca0
Summary:
Previously we would only simplify when the term is exactly IsInstanceOf,
and skip sub-terms. Most of the time this is the case but in the future
this could change.
Reviewed By: skcho
Differential Revision: D27156519
fbshipit-source-id: bd10574e0
Summary:
- some editing of the text
- the documentation of NULLPTR_DEREFERENCE was duplicated in
NULL_DEREFERENCE. Make the latter point to the former instead.
Reviewed By: skcho
Differential Revision: D27162785
fbshipit-source-id: 442d6efb9
Summary:
In Pulse, it usually havoc the actual parameters to unknown functions. However, it did not do that when the lengths of actuals and formals mismatch, which may happen when the frontend doesn't have enough information about procedures.
This diff havoc the actual parameters, also when there is mismatch between lengths of actuals and formals.
Reviewed By: ezgicicek
Differential Revision: D27163143
fbshipit-source-id: 1c5e0853a
Summary:
Two methods with identical method names but different number/type of args will have the same hash: e.g. `foo(int x)` and `foo(int x, int y)`. For Config Impact analysis, we assumed this type of hash collusion would never happen when we are comparing config-impact reports, but that assumption is wrong as demonstrated by the modified tests.
To deal with these, in cost analysis, we pick the highest degree among the potential collisions. We follow a similar idea here, picking the highest number of unchecked callees.
That has its own disadvantages:
E.g. giving an example from cost, if we had `foo(int x)` with O(1) before, and after the change, we have also added a linear `foo(int x, int y)`, I think we would introduce a complexity increase.
Still, it is better than picking only the first/last.
Reviewed By: skcho
Differential Revision: D27156722
fbshipit-source-id: c37388f1c