Summary: At a function call, an access performed by a callee must be processed in various ways before it's added to the accesses of the caller, and several of these steps may throw away the access. Previously, this was done by effectively doing a bit of transformation, creating a new set of accesses, then folding over that to add to the caller's. This is inefficient and somewhat confusing, as this can be done with one fold and a sequence of `Option.map`s.
Reviewed By: skcho
Differential Revision: D24885117
fbshipit-source-id: 4ab61eab9
Summary:
Existing closure substitution only supported direct block calls to formals.
The following didn't work since the domain was only keeping track of loads/calls from formals, but didn't support stores.
```
void foo(dispatch_block_t block1){
dispatch_block_t local_block = block1;
local_block(); // we don't substitute the call here
}
```
This diff adds support for assigning a block to a local variable so that we can specialize the above example.
We now have a pair domain
- existing mapping from ids to block vars
- a new mapping from mangled to block specializations
the latter allows us to update the mapping in local block assignment (via store).
Reviewed By: skcho
Differential Revision: D25030234
fbshipit-source-id: 3f172341c
Summary:
Specialized closure substitution was broken for conditionals:
```
void foo(dispatch_block_t block1){
if (x){
block1(); // not replaced with specialized implementation
}
}
```
The problem was that when substituting function calls, it only used memory state at the exit node, rather than at each program point.
We could solve this by
- reverting the domain change in D24418560 (c47911359a), i.e. collecting all possible mappings conservatively (e.g. switch the domain back to `Map`)
- pass the `invariant_map` for substitutions at each program point.
We go with the second option here.
The closure substitution is still somewhat broken as exemplified by the following example:
```
void foo(dispatch_block_t block1){
dispatch_block_t local_block = block1;
local_block(); // we don't substitute the call here
}
```
Reviewed By: skcho
Differential Revision: D24993962
fbshipit-source-id: ebadddb58
Summary:
A minor but persistent annoyance: named argument of a non-ambiguous type
of almost the same name. No.
Reviewed By: skcho
Differential Revision: D24991673
fbshipit-source-id: c806f9cec
Summary:
This was left as a TODO before: where to place calls to destructors for
C++ temporaries that are only conditionally creating when evaluating an
expression. This can happen inside the branches of a conditional
operation `b?e:f` or in potentially-short-circuited conditions on the
righ-hand side of `&&` and `||` operators.
Following the compilation scheme of clang (observed by looking at the
generated LLVM bitcode), we instrument the program with "marker"
variables, so that for instance `X x = true?X():y;` becomes (following
the execution on the true branch):
```
marker1 = 0; // initialize all markers to 0
PRUNE(true) // entering true branch
X::X(&temporary); // create temporary...
marker1 = 1; // ...triggers setting its marker to 1
X::X(&x, &temporary); // finish expression
if (marker1) {
X::~X(&temporary); // conditionally destroy the temporary
}
```
In this diff, you'll find code for:
- associating markers to temporaries that need them
- code to initialize markers to 0 before full-expressions
- code to conditionally destroy temporaries based on the values of the
markers once the full-expression has finished evaluating
Reviewed By: da319
Differential Revision: D24954070
fbshipit-source-id: cf15df7f7
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:
The current source parser is based on ocamllex only.
In order to track field declaration locations, we propose a
new parser using ocamllex/menhir. This is a more ambitious
project that closely follows the official Java syntax.
Reviewed By: jvillard
Differential Revision: D24858280
fbshipit-source-id: 22d6766e5
Summary:
These are not simply handled by `@deriving` since:
- These types are recursive and so some fields need to be ignored
- Some are uniquely identified by one of their fields
- Some fields are mutable, but set only during construction, and need
to be considered by compare, equal, hash, but ppx_hash refuses.
Reviewed By: jvillard
Differential Revision: D24989064
fbshipit-source-id: 7f8d699e5
Summary:
The use of realpath on paths obtained from debug info and the current
working directory is application-usage-specific behavior that does not
belong in the backend library. This diff moves these uses to the
frontend and cli, respectively. Also, the use of realpath in the
frontend is memoized along the same lines as the other frontend
translation functions.
This was also the last use of `core` in the `sledge` library, so the
dependency is moved to `sledge_cli` and `sledge_report`.
Reviewed By: ngorogiannis
Differential Revision: D24989070
fbshipit-source-id: c21b275f5
Summary:
Currently __llair_choice is left undefined, and so executed as skip.
This has the correct behavior, but makes it hard to distinguish from
calls to unintentionally-undefined procedures.
Reviewed By: ngorogiannis
Differential Revision: D24989068
fbshipit-source-id: f62981857
Summary:
Use B/K/M/G/... units for memory quantities, round percentages to 2
decimal places, and robustly detect deltas of close to zero.
Reviewed By: ngorogiannis
Differential Revision: D24989063
fbshipit-source-id: 35f0bccfb
Summary:
Instructions that have multiple specs sometimes have inconsistent
footprints for one or more of their specifications. In such cases, the
handling of the existential and universal vocabularies was sometimes
incorrect before this diff. In particular, the ghosts of a spec need
not appear in the pure approximation of the footprint, which the
previous code incorrectly assumed. Also, the unit of disjunction is
`false` with an empty vocabulary, not the precondition's vocabulary as
the previous code incorrectly used.
Reviewed By: ngorogiannis
Differential Revision: D24989067
fbshipit-source-id: eca3bff55
Summary:
Change `-llair-output` to `-output`, for binary form, and
`-llair-txt-output` to `-llair-output`, for textual form. Also
correspondingly change `.llair` to `.bllair`, for binary, and
`.llair.txt` to `.llair` for text.
This improves command line argument completion, and makes `.llair` the
extension of the files most commonly interacted with.
Reviewed By: ngorogiannis
Differential Revision: D24951506
fbshipit-source-id: ad4c73ca2
Summary:
The `seq` name of this field refers to the expected sort of it's
value, where the others refer to the role they play. So rename
seq (for sequence) to cnt (for contents).
Reviewed By: ngorogiannis
Differential Revision: D24951507
fbshipit-source-id: fd6640517
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:
Sometimes there are annotations that don't correspond to the user facing
code.
Previously we would fail, now process them gracefully.
Reviewed By: artempyanykh
Differential Revision: D24890895
fbshipit-source-id: e64a866ec
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:
- The SDK path is different for Objective C when command line tools for Xcode are installed without Xcode itself.
- Related issue https://github.com/facebook/infer/issues/1002.
I still have a problem with the mentioned issue. I think that it is possible that the SDK paths differs for Objective C on Mac OS when I have installed just command line tools for Xcode without Xcode itself. This change solves the issue for me. Is it a good solution? Could it be possibly added to Infer? Or is there any better way?
Pull Request resolved: https://github.com/facebook/infer/pull/1345
Reviewed By: ngorogiannis
Differential Revision: D24917636
Pulled By: jvillard
fbshipit-source-id: 534ce4b49
Summary: It is too easy to mix up multiple arguments of the same type.
Reviewed By: jvillard
Differential Revision: D24934116
fbshipit-source-id: 6e595b26e
Summary:
Global constants have reliable types, and their sizes can be used
instead of storing the size of the initializer separately.
Reviewed By: jvillard
Differential Revision: D24934114
fbshipit-source-id: 2426ab5be
Summary:
In practice this has not been observed to matter so far, since
treating `Splat N` as interpreted or uninterpreted does not matter
when `N` is a literal constant, and code seen so far only uses `Splat`
for zero initializers or memset with literal constant bytes.
Reviewed By: jvillard
Differential Revision: D24934118
fbshipit-source-id: 213e9724e
Summary:
optimize the git clone using --depth flag in term of size of clone
and also in term's of time taken to fetch the files and commit history
of whole repository .
More detail can be found at blog
https://www.atlassian.com/git/tutorials/big-repositories
Signed-off-by: Pratik Raj <rajpratik71@gmail.com>
Pull Request resolved: https://github.com/facebook/infer/pull/1341
Reviewed By: da319
Differential Revision: D24917645
Pulled By: jvillard
fbshipit-source-id: 6764fc971
Summary:
In the next diff we need to know when a destructor is needed for sure
before calling some of these auxiliary methods.
Reviewed By: da319
Differential Revision: D24832078
fbshipit-source-id: 6d4e17de2
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:
0 and Splat 0 need to be treated the same since code relies on knowing
that 0 consists of all-0 bytes, and extracting a subsequence of a
Splat 0 yields 0. For example, initializing a struct to all-zeros and
then reading a member of pointer type out of it needs to produce the
null pointer. Therefore 0 and Splat 0 are redundant representations,
and all uses of Splat need to be updated to also handle 0.
This unfortunately leads to some near code duplication that seems to
be necessary. The issue is that 0 and Splat 0 are, from the backend's
perspective, constants in two distinct theories. Since 0 is chosen
over Splat 0 as the representation, the sequence theory solver needs
to treat 0 as if it was Splat 0, which duplicates some code handling
the general Splat cases.
Reviewed By: jvillard
Differential Revision: D24920758
fbshipit-source-id: 7c02be62b
Summary:
Global variables and function names in LLAIR are constant and so do
not need to be handled like normal assignable or shadowable
variables. This diff does this by changing the translation from LLAIR
to FOL to map globals and functions to uninterpreted constants instead
of variables.
Reviewed By: jvillard
Differential Revision: D24886571
fbshipit-source-id: efb8c9f49
Summary:
Localizing the entry of a procedure needs the globals (that the
procedure uses), but later creating a summary does not.
Reviewed By: jvillard
Differential Revision: D24886570
fbshipit-source-id: 8a7b18c58
Summary:
The computation of provable reachability through the heap currently
uses a set of variables whose values are either determined by the
desired roots or by the heap constraints. This requires globals to be
treated as variables. In preparation for distinguishing globals from
variables, this diff changes the reachability computation to use a set
of atomic terms instead of variables.
Reviewed By: jvillard
Differential Revision: D24886573
fbshipit-source-id: c0e6763b6
Summary:
No functional change, only simplifiying and making easier to
generalize.
Reviewed By: jvillard
Differential Revision: D24886572
fbshipit-source-id: e487b815d