Summary:
This diff fixes two issues in the backend that were causing Bad_footprint
errors when abducing pointsto facts for expressions that start in an array
access and follow up with another structured access, eg `x[0].some_field`:
1. array accesses were assumed to come last in these expressions
2. the type of the root exp passed to the function that walks down the list of
offsets to apply to it was wrong in the case of arrays: it was always the
type of the whole expression instead of the root expr (eg the type of
`x[0].some_field` instead of the type of `x`).
Reviewed By: sblackshear, jeremydubreil
Differential Revision: D3800566
fbshipit-source-id: 0511604
Summary:
Infer doesn't go looking into field values when looking for unsigned
expressions, which could cause some unintended reports.
Reviewed By: sblackshear
Differential Revision: D3724232
fbshipit-source-id: 9c4cd97
Summary:
Refactor module Prop disentangling the various normalization functions, and moving them inside a new module Normalize.
There is quite a reshuffling of functions, including some dead code removal, but there should be no computational difference.
Reviewed By: jvillard
Differential Revision: D3696491
fbshipit-source-id: 68dd719
Summary:
Clean up the API to access component of propositions.
Use uniform naming for getting and setting components.
Reviewed By: jberdine
Differential Revision: D3696180
fbshipit-source-id: a8aedb0
Summary:
This diff lifts the Prop.Attribute module out of Prop. This required
moving several Prop functions that depend on Attribute
(find_arithmetic_problem, deallocate_stack_vars, find_equal_formal_path)
and adding numerous calls to Prop.normalize to fix normal/exposed
mismatches. Also note that the type of Prop.normalize is generalized to
allow calling it on normalized props.
Reviewed By: cristianoc
Differential Revision: D3684523
fbshipit-source-id: f37af8b
Summary:
Move the Sil.attribute type and associated types and operations to a new
PredSymb module.
Reviewed By: cristianoc
Differential Revision: D3683834
fbshipit-source-id: d3606a8
Summary:
Add support for nary predicates, not just unary ones. Many operations
don't make much sense for nullary predicates, and are generally treated
as no-ops. The first argument is treated specially, as the "anchor" of
the predicate application. For example, adding or removing an attribute
uses the anchor to identify the atom to operate on. Also, abstraction
and normalization operations treat the anchor specially.
Reviewed By: cristianoc
Differential Revision: D3669391
fbshipit-source-id: 3d142ea
Summary:
Simplify the (implementation and) interface of Prop by using the atom
type directly instead of a tuple type that duplicates the fields.
This change does not weaken the type guarantees, while reducing
redundancy between types thereby making future changes easier.
Reviewed By: cristianoc
Differential Revision: D3669388
fbshipit-source-id: 65f7493
Summary:
Treat attributes as unary predicates in classical first-order logic.
This diff extends predicates with a polarity and uses classical 2-valued
semantics. This potentially changes the behavior of negating
attributes, which was not previously relied on.
Reviewed By: sblackshear
Differential Revision: D3669365
fbshipit-source-id: 2f26776
Summary:
Replace disequalities to Attribute expressions with predicate symbol
application pure atomic formulas.
This diff should preserve existing behavior, up to the comparison order
of attribute disequalities versus predicate applications.
Reviewed By: sblackshear
Differential Revision: D3647049
fbshipit-source-id: c39a901
Summary: Move Sil.binop type and operations into separate Binop module.
Reviewed By: dulmarod
Differential Revision: D3548082
fbshipit-source-id: 356bee3
Summary: Move Sil.const type and operations into separate Const module.
Reviewed By: dulmarod
Differential Revision: D3548073
fbshipit-source-id: 388d03e
Summary:
Move attribute values from const to exp. They are not constants, and
this reduces interdependence between Sil types.
Reviewed By: cristianoc
Differential Revision: D3548055
fbshipit-source-id: 31a9121
Summary: Use Prop.atom_negate in Rearrange instead of almost reimplementing it.
Reviewed By: sblackshear
Differential Revision: D3554171
fbshipit-source-id: 9baabc9
Summary:
Now that array types record only static - and therefore constant -
lengths, Sil typ and exp no longer need to be mutually recursive.
This diff:
- splits the recursion in the type definitions of typ and exp,
- splits the recursion in the comparison and pretty-printing
functions,
- and then refactors typ into a separate module.
Reviewed By: cristianoc
Differential Revision: D3423575
fbshipit-source-id: 6130630
Summary:
This diff refactors Sil.Int, which represents integer literals, into a
separate module IntLit. There are no dependencies forcing Sil.Int to
be a submodule of Sil, and it is also no simpler as a submodule.
Reviewed By: cristianoc
Differential Revision: D3422910
fbshipit-source-id: 63013f2
Summary:
Array types where the length is not statically known were represented
using fresh variables. This diff:
- Makes array type length optional, reducing the amount of work needed
for renaming, substitution, and normalization.
- Revises uses of array length so that the length component of a
Tarray type represents only the statically determined constant
length of an array type, and the length component of a Sizeof
expression represents the dynamically determined length of an array
value.
- Restricts the type of static lengths from a general expression
(Sil.exp) to an integer (Sil.Int.t), enforcing that static types are
constant. This in particular ensures that types contain no
variables, and so are invariant under operations such as renaming
and substitution.
- Removes the type substitution and renaming functions typ_sub,
typ_normalize, and typ_captured_ren. Now that array type lengths
are constant integers, all of these functions are the identity.
Reviewed By: cristianoc
Differential Revision: D3387343
fbshipit-source-id: b5db768
Summary:
This diff extends Sizeof expressions with an optional expression for the
length of the final extensible array, if any. For example, sizeof a
simple array `sizeof(t[n])` is represented by (modulo subtyping info)
`Sizeof t (Some n)`, and sizeof a struct whose final member is an array
`sizeof(struct s {... t[n] f})` is represented by `Sizeof (struct s
{... t[n] f}) (Some n)`.
This is an intermediate step toward eliminating expressions from types,
the redundancy between the length in the types and in the sizeof
expressions will be eliminated later.
Reviewed By: cristianoc
Differential Revision: D3358763
fbshipit-source-id: 2239bca
Summary:
Make analyzer find out when null dereference comes from std::vector method.
If it does, it means that it's really empty vector access (due to the
way infer models std::vector)
Reviewed By: sblackshear
Differential Revision: D3327933
fbshipit-source-id: b9e11d6
Summary:
If we see a read of a field f annotated with GuardedBy("mLock"), we spring into action.
What we do is look for some hpred `A.mLock |-> B` and return `B` as the "guarded-by object".
Once we have models for montitorenter/exit in place, `B.__inferIsLocked = true` will mean "lock held", and `B.__inferIsLocked = false` will mean "lock not held".
Reviewed By: jvillard
Differential Revision: D3316288
fbshipit-source-id: 8625e04
Summary:
Reimplement command line options in preparation for uniformly passing
options from the top-level infer driver that invokes a build command
through the build system to the descendant infer processes.
All command line options of all executables are collected into Config,
and declared using a new CommandLineOption module that supports
maintining backward compatibility with the current command line
interface. Very few values representing command line options are
mutable now, as they are set once during parsing but are constant
thereafter. All ordering dependencies are contained within the
implementation of Config, and the implementation of Config is careful to
avoid unintended interactions and ordering dependencies between options.
Reviewed By: jvillard
Differential Revision: D3273345
fbshipit-source-id: 8e8c6fa
Summary:public
Eliminate the use of the -open Utils command line option passed to the compiler in favor of `open! Utils` in each source file. While slightly convenient, this option causes more headaches than it is worth with other tools e.g. merlin.
Reviewed By: jvillard
Differential Revision: D3168193
fb-gh-sync-id: 4285ef6
fbshipit-source-id: 4285ef6
Summary:public
I have seen enough comments in this space by people during code review to switch on the analyses the compiler can already do. This diff is an automated renaming of unused identifiers to _, with a few additional changes made when reading the diff of the results for things that stood out as particularly strange. This base-lines all of the existing warnings. I'm not sure this is a good idea, since it might be better for those familiar with each part of the code to look at these warnings and use them as pointers to suspicious code.
Reviewed By: jeremydubreil
Differential Revision: D2938376
fb-gh-sync-id: 6e67817
shipit-source-id: 6e67817
Jules Villard
Sam Blackshear
Cristiano Calcagno
Josh Berdine
Dulma Churchill
Peter O'Hearn
Andrzej Kotulski