Summary:
`typecheck_instr` is a function that essentially does most of nullsafe typechecking
work: it pattern matches the instruction and handles most of business logic (e.g. knowledge about builtins, rules of PropagatesNullable, flow-sensitive rule for condition branches etc etc etc.
This is a gigantic function consisting of huge amount of nested
function. No way it can fit in someone's head and it is super hard to
read. It also captures many things like node and node'.
This diff does fairly shallow work:
1. Moves most of nested subfunctions into top-level functions. It also
means that what was previously hiddenly captured is now made an explicit
dependency.
2. Some (minority) of them are renamed to better indicate the context.
3. Some (minority) of params are renamed to clear indicate the
difference.
4. Some params are made named params, especially booleans and params
that have the same types so could be confused.
5. In some placed, added bit more clear comments.
This diff DOES NOT do:
1. Tries to fully resolve confusion between cryptic names. In couple of places, instead of node'
and node we use node and original_node, which is barely better. But we
still have ugly things like typestate and typestate1 leaving together.
Baby steps!
2. Tries to create better or consistent names in functions. I did it for
most obvious cases, that's it.
3. Order or params is arbitrary. I just used the order that was easy to
come up with, no consistency here.
Reviewed By: artempyanykh
Differential Revision: D18425965
fbshipit-source-id: 7a775f08d
Summary:
This diff extends bound domain to express Min/Max of another bounds, so it can keep some more
precision in `Math.min/max`.
limitation: `MinMaxB`, the constructor of the bound, can contain only linear expressions or
previous min/max expressions.
Reviewed By: ezgicicek
Differential Revision: D18395365
fbshipit-source-id: fc90d27fd
Summary:
We still have few remaining places which we have a logic not encoded in
as a Nullability type. Ignoring third party param calls is one of them.
We don't want this behavior for strict mode.
Reviewed By: artempyanykh
Differential Revision: D18396639
fbshipit-source-id: dbfedc769
Summary:
The upcoming whole-program analysis will need to log reports in different source files simultaneously.
Here, the data structure containing the reports, and in charge of deduplication is generalised to
a map from source file to what it was previously. This way, writing out the reports is possible even
with multiple source files.
Reviewed By: skcho
Differential Revision: D18394994
fbshipit-source-id: 5f5ecc27c
Summary:
The old version of simp_convert in LLAIR had a bug, but the sanity
theorem didn't catch it because it didn't enforce that the result fit
into the size it should have. This updates to newer version of
simp_convert and adds a theorem that the result fits.
Reviewed By: jberdine
Differential Revision: D18346833
fbshipit-source-id: 533c836bf
Summary:
This is a dirty hack to make nullsafe behave consistently for internal
and external models.
Medium term this code needs to be rewritten in a better way, so that we
pass all information in annotated signature (either in form of Inferred
nullability, or type origin, which tracks third party calls).
As a follow up, we will make reporting more clear.
Reviewed By: artempyanykh
Differential Revision: D18372660
fbshipit-source-id: 12c2449e1
Summary: Capture locations where work is scheduled to run in parallel (here, just Executors). Also add a test file with cases the upcoming whole-program analysis for starvation should catch.
Reviewed By: dulmarod
Differential Revision: D18346880
fbshipit-source-id: 57411b052
Summary:
Ability to accept relative path is convenient for testing and local
debugging.
Ability to accept absolute paths is needed for buck integration - buck
knows absolute path (to properly invalidate cache when the content of
the folder is changed) and passes it to infer.
Reviewed By: artempyanykh
Differential Revision: D18370407
fbshipit-source-id: be7f12ae1
Summary: Follow ups will include error messaging that makes the choice clear
Reviewed By: artempyanykh
Differential Revision: D18347664
fbshipit-source-id: b6f005726
Summary:
In this diff, we just load the info from the storage. Next diff will be
actually using this information to infer nullability.
`ThirdPartyAnnotationGlobalRepo.get_repo` will be used in the next diff,
hence #skipdeadcode
Reviewed By: artempyanykh
Differential Revision: D18347647
fbshipit-source-id: 82a9223c6
Summary:
In next diffs, we will:
1/ teach nullsafe to read nullability information from the 3rd party
annotation folder
2/ use this storage in addition to our hard-coded
models to respect nullability during type-checking
Reviewed By: artempyanykh
Differential Revision: D18247538
fbshipit-source-id: ee45bc80e
Summary:
Extend the APRON-backed interval analysis to handle a wider range
of LLAIR expressions.
Reviewed By: jvillard
Differential Revision: D17858072
fbshipit-source-id: c50f5bf20
Summary:
This diff extends the alias domain, so each variable can have multiple aliases.
It changed `KeyLhs` can be mapped to multiple alias targets in the `AliasMap` domain:
```
before : KeyLhs.t -> KeyRhs.t * AliasTarget.t
after : KeyLhs.t -> KeyRhs.t -> AliasTarget.t
```
Reviewed By: ezgicicek
Differential Revision: D18062178
fbshipit-source-id: b325a6055
Summary:
It extracts RHS of alias from `AliasTarget.t`, so it changes the `AliasMap` domain:
```
before : KeyLhs.t -> AliasTarget.t // AliasTarget.t includes KeyRhs.t
after : KeyLhs.t -> KeyRhs.t * AliasTarget.t
```
Reviewed By: ezgicicek
Differential Revision: D18299537
fbshipit-source-id: 1446580a8
Summary:
Pretty trivial, but important in case GitHub will stop redirecting.
Pull Request resolved: https://github.com/facebook/infer/pull/1177
Differential Revision: D18347364
Pulled By: jvillard
fbshipit-source-id: b4e632780
Summary: We only care about expensive invariant calls. Let's disable the usual one since it is not used and there is no point filling up our dbs.
Reviewed By: dulmarod
Differential Revision: D18298530
fbshipit-source-id: 7a933c8da
Summary:
More rigid format for 3rd party annotation repo
To simplify external processing by tools, lets not accept any divergence from a
format, which is:
<fully qualified class name>#<method_name>(<params>)[ Nullable]
<params> = <list of param separated by ", ">
<param> = [Nullable ]<fully qualified type>
Particularly:
- Dont accept spaces in arbitrary places
- Require a single space after each comma separating params
- Require a single space between closing parethesis and nullable
annotation, if present
- Require at least one '.' in a class name (to prevent errors when
somebody did not specify a package).
This diff also makes error messaging more user-friendly, because now it
is easy to do a minor mistake like forget a space after comma.
Reviewed By: asm89
Differential Revision: D18297382
fbshipit-source-id: 91aab6823
Summary:
In some cases the result of an integer conversion needs to be
truncated by a bit.
Differential Revision: D18271179
fbshipit-source-id: e80740045
Summary:
This diff tries to make less imprecise division by constants results.
For example, the results of the division `[l, u] / c`, where `c` is a positive constant, are:
1. If `l/c` or `u/c` is representable in the bound domain, it uses the precise bounds, i.e., `[l/c, u/c]`.
2. If it is not representable, it tries to make conservative results:
if `0<=l<=u`, it returns `[0, u]` because `0 <= [l/c, u/c] <= u`
if `l<=u<=0`, it returns `[l, 0]` because `l <= [l/c, u/c] <= 0`
if `l<=0<=u`, it returns `[l, u]` because `l <= [l/c, u/c] <= u`
3. otherwise, it returns top, `[-oo, +oo]`
Reviewed By: ezgicicek
Differential Revision: D18270380
fbshipit-source-id: 8fb14c0e4
Summary:
Add precision to analysis by elaborating the thread-status domain. This is done by having unknown (bottom), UI, BG or Any (both/top) elements in the lattice. This way, when we branch on thread-identity (if I am on UI thread do this, otherwise do that), we know that in one branch we are on UI thread and on the other we are *not* on the UI thread (BG thread), where previously the other branch would just go to top.
With this knowledge we can throw away pairs that come from callees which run on a thread that is impossible, given the current caller thread identity. This can happen when annotations are used incorrectly, and since this is the purview of annot-reachability, we just drop those pairs entirely.
Reviewed By: skcho
Differential Revision: D18202175
fbshipit-source-id: be604054e
Summary:
Improve the invariants to show that phi instructions are correctly
translated. It remains to show that the invariants can be established
when jumping to the start of a block
Reviewed By: jberdine
Differential Revision: D18228272
fbshipit-source-id: 4330b4781
Summary:
Now that we have two similar functions, it becomes confusing, because `Pp.to_string` and `Pp.string_of_pp` can seem to do the same stuff, while in reality they do the opposite.
Well, it is still bit confusing, because the proper names would be
`Pp.pp_of_to_string` and `Pp.to_string_of_pp`, but I think this high
level order names are not necessary given that in most cases they will
be used as concrete functions.
I think `Pp.of_string` captures such usages better than `to_string` used to do: you need to pp stuff,
but you have a string (or, technically, a function that returns a string), so you pretty print OF that string, aren't you?
Reviewed By: jvillard
Differential Revision: D18245876
fbshipit-source-id: fd4b6ab68
Summary:
This is a helper module for reading info from a 3rd party nullability repository.
Next diffs are going to use it for reading nullability repository from
disk.
Reviewed By: artempyanykh
Differential Revision: D18225473
fbshipit-source-id: 06a2dc97e
Summary:
We see failures in the Travis CI which may be related to known issues in earlier versions of mlgmpidl.
Facebook
Reviewed By: jvillard
Differential Revision: D18244267
fbshipit-source-id: 9889c9c86
Summary:
Steal a page from RacerD (and improve interface of) on using certain calls to assert
execution on a particular thread. Reduces FPs and FNs too.
Reviewed By: dulmarod
Differential Revision: D18199843
fbshipit-source-id: 5bdff0dfe
Summary:
The zero cost of node does not make sense especially when the abstract memory is non-bottom. This
resulted in unreasonable zero cost results sometimes, e.g. when the checker could not find
appropriate control varaibles having interval values of iteration. This diff fixes this, so sets
the minimum basic cost as 1, if the abstract memory at the node is non-bottom.
Reviewed By: ezgicicek
Differential Revision: D18199291
fbshipit-source-id: b215d10e5
Summary:
When reporting null dereference it is useful to know where the null came
from.
Reviewed By: skcho
Differential Revision: D18206459
fbshipit-source-id: 0c8e6781b
Summary:
This simplifies the code overall. It also makes accessing the action of
a "trace" (which is now stored alongside it instead of deep inside it)
constant time instead of linear in the number of nested calls.
Reviewed By: skcho
Differential Revision: D18206460
fbshipit-source-id: 9546ff36f
Summary:
This adds a more interesting value domain to pulse: concrete intervals.
There are still two main limitations:
1. arithmetic operations are all over-approximated: any assignment involving arithmetic operations is replaced by non-determinism
2. abstract values that are discovered to be equal are not merged into one
Reviewed By: skcho
Differential Revision: D18058972
fbshipit-source-id: 0492a590f
Summary:
This does several things because it was hard to split it more:
1. Split most of the arithmetic reasoning to PulseArithmetic.ml. This
doesn't need to be reviewed thoroughly because an upcoming diff
changes the domain from just `EqualTo of Const.t` to an interval domain!
2. When going through a prune node intra-procedurally, abduce arithmetic
facts to the pre (instead of just propagating them). This is the "assume
as assert" trick used by biabduction 1.0 too and allows to propagate
arithmetic constraints to callers.
3. Use 2 when applying summaries by pruning specs whose preconditions
have un-satisfiable arithmetic constraints.
This changes one of the tests! Pulse now does a bit more work to find
the false positive, as can be seen in the longer trace.
Reviewed By: skcho
Differential Revision: D18117160
fbshipit-source-id: af3b2c8c0
Summary:
Instead of checking that each address in the pre that must be valid is
not invalid in the caller (and error out if it turns out it is invalid)
as we discover them, save these checks for after we are sure that the
precondition can be applied. It is in fact a bug that we can report an
error when trying to apply a precondition that is actually not
satisfiable in the current state for other reasons than lifetime issues.
We still want to skip calls in case of weird issues like mismatch in
number of formals vs actuals.
This will have more obvious effects later when we also check that
arithmetic facts in preconditions are satisfied at the call site: if a
pre mandates "x=1" and "y must be valid" and we have "x=0" and "y
invalid" then we shouldn't report an error.
Reviewed By: skcho
Differential Revision: D18115229
fbshipit-source-id: ad4ce72ff
Summary:
If a precondition cannot be applied, it means that this program path
somehow doesn't make sense for the caller and so should be pruned. Right
now we just treat this as skipping over the call instead.
This will become more important when specs start mentioning arithmetic
facts that must be satisfied at the call site. As it is we will only
stop if we discover aliasing in the pre not present at the call site or
vice versa.
Reviewed By: dulmarod
Differential Revision: D18115230
fbshipit-source-id: 4f1c7a583
Summary: The way `<=` is used in `AbstractDomain` prevents infix use and forces bracketing it everywhere. Replace with simple `leq`.
Reviewed By: jvillard
Differential Revision: D18201854
fbshipit-source-id: 8175224e4
Summary:
Add a new interval abstract domain. This domain uses the APRON
numerical analysis library to keep track of the range of values held
by llair variables where possible. This works by translating LLAIR
expressions into APRON tree expressions, so only handles the
subset of the LLAIR expression language that can be embedded.
Note also that function summarization is not yet implemented.
Future commits will add summarization and improve coverage of
LLAIR's expression language.
Reviewed By: jberdine
Differential Revision: D17763517
fbshipit-source-id: 826ce4cc5
Summary: Abstract state tracks stuff that is not needed for summaries, wasting space/time.
Reviewed By: jvillard
Differential Revision: D18171499
fbshipit-source-id: 25483ced9
Summary:
Primitive types are not annotated. Because of that, we used to implicitly derive
`DeclaredNonnull` type for them. This worked fine, but this leads to errors in Strict mode, which does
not believe DeclaredNonnull type.
Now lets offifically teach nullsafe that primitive types are
non-nullable.
Reviewed By: jvillard
Differential Revision: D18114623
fbshipit-source-id: 227217931
Summary:
This diff adds SafeInvertedMap, which is similar to InvertedMap but it
guarantees that there is no top elements in the tree of the map.
Reviewed By: ezgicicek
Differential Revision: D18062174
fbshipit-source-id: 2fbc51f31
Mitya Lyubarskiy
Sungkeun Cho
Nikos Gorogiannis
Scott Owens
Dulma Churchill
Ezgi Çiçek
Benno Stein
Anton Kochkov
Amar Paul
Josh Berdine
Jules Villard
Martin Trojer