Summary: It simplifies instantiataion of `ret_alias`. While it got `ret_alias` values by iterating caller's and callee's memory, now it gets `ret_alias` by evaluating symbol paths included in location values.
Reviewed By: mbouaziz
Differential Revision: D9569606
fbshipit-source-id: a3326bb81
Summary:
It simplifies abstract memory instantiations of function calls. Now it instantiates callee memories by directly evaluating symbol paths, rather than constructing `subst_map`.
main changes are:
- no construction of `subst_map` and `trace_map`
- no symbol table in Inferbo's summary
- no `Symbol_not_found` exception (for when a required symbol was unavailable in `subst_map`)
Reviewed By: mbouaziz
Differential Revision: D9495597
fbshipit-source-id: 18cdcd6f7
Summary:
- Was not used by the caller
- Gives smaller summaries
- Will allow adding a intra-proc info, e.g. `node` for reporting (not sure yet)
Reviewed By: skcho
Differential Revision: D9373763
fbshipit-source-id: 322001b53
Summary:
In SIL, (1) some program variables (e.g., array parameter) are used as pointers to heap addresses and (2) the other program variables (e.g., local array) are used as addresses themselves. So, the values of (1) are retrieved by the `Load` command, while that of (2) are by `Exp.Lvar` expressions directly.
To address them differently, we had managed two maps (`Mem.Stack` and `Mem.Heap`), but which introduced function duplications on abstract memory and increased complexity. This diff merges the two maps, and instead a location set is used for distinguishing two types of abstract locations during analysis.
Reviewed By: mbouaziz
Differential Revision: D9420388
fbshipit-source-id: 13f824850
Summary:
It returns unknown values on non-const function calls like on unknown
function calls.
Reviewed By: mbouaziz
Differential Revision: D9478862
fbshipit-source-id: 4b795ec55
Summary: It uses a SymbolPath map to Symbol in Inferbo's summary instead of an entry memory of callee, which is used for instantiations of the abstract memories on function calls.
Reviewed By: mbouaziz
Differential Revision: D9081631
fbshipit-source-id: 478cda0de
Summary:
It adds relational domains to Inferbo: octagon of Apron and polyhedra of Elina.
- Each Mem domain value includes one relational value containing relations among symbols. The relational values are modified by the `Prune` and `Store` commands.
- Each abstract value includes three symbols, which represent integer value, array offset, and array size of an abstract value.
The relational domain is deactivated by default. Use the `--bo-relational-domain {oct, poly}` option for the activation, though Inferbo with the relational domains does not work at this point because some modifications of Apron and Elina we made has not been applied to their opam repositories yet.
Reviewed By: jvillard
Differential Revision: D8874102
fbshipit-source-id: 08e5883cb
Summary: `IntLit.to_int` could raise, was not documented until recently and was not named `_exn`. Switch to option type and fix uses.
Reviewed By: jeremydubreil
Differential Revision: D8865525
fbshipit-source-id: f5ec2f221
Summary:
It adds relational domains to Inferbo: octagon of Apron and polyhedra of Elina.
- Each `Mem` domain value includes one relational value containing relations among *symbols*. The relational values are modified by the `Prune` and `Store` commands.
- Each abstract value includes three *symbols*, which represent integer value, array offset, and array size of an abstract value.
The relational domain is deactivated by default, so this diff should not make any differences in CI.
Use `--bo-relational-domain {oct, poly}` for the activation, though Inferbo with the relational domains does not work at this point because some modifications of Apron and Elina we made has not been applied to their opam repositories yet.
Reviewed By: mbouaziz, jvillard
Differential Revision: D8478542
fbshipit-source-id: 510ff53
Summary:
Having the `Node` module including in the `CFG` one is confusing.
Let's keep it separate.
Reviewed By: ngorogiannis
Differential Revision: D8185754
fbshipit-source-id: 62077e6
Summary:
Change the license of the source code from BSD + PATENTS to MIT.
Change `checkCopyright` to reflect the new license and learn some new file
types.
Generated with:
```
git grep BSD | xargs -n 1 ./scripts/checkCopyright -i
```
Reviewed By: jeremydubreil, mbouaziz, jberdine
Differential Revision: D8071249
fbshipit-source-id: 97ca23a
Summary:
For now: just moving this list behind an abstract type.
Next: changing the internal representation.
Reviewed By: ngorogiannis
Differential Revision: D8140926
fbshipit-source-id: 5b959b0
Summary:
We never really need the list of nodes/succs/preds, we only need to fold over them.
This will reduce garbage for computed lists like in the Exceptional CFG or the OneInstrPerNode CFG.
Reviewed By: ngorogiannis
Differential Revision: D8185665
fbshipit-source-id: d042beb
Summary:
Preparing for bigger changes...
- Rename `payload` field to `payloads`
- Move `payload` type to `Payloads.t`
- `SummaryPayload`s only have to implement a change on `Payloads.t` rather than `Summary.t`
Reviewed By: sblackshear
Differential Revision: D7987211
fbshipit-source-id: c9d7a74
Summary:
Attempt at a better naming scheme:
- `Specs.summary` are now `Summary.t`. The `Summary` module (replacing `Specs`) contains the summary of a procedure: the results of all the analyses, etc.
- `Summary.ml` is now `SummaryPayload.ml`. This concerns how each (AI) analysis extracts its payload from the master summary.
- Accordingly, checkers now define a `Payload` module where previously they defined a `Summary` module. The type is also cleaned up to use `t` instead of `payload`, etc.
- Cleaned up some names as a result, for instance `Specs.get_summary` -> `Summary.get`, etc.
Reviewed By: ngorogiannis
Differential Revision: D7935883
fbshipit-source-id: 1766545
Summary:
This simplifies the frontends and backends in most cases. Before this diff,
returning `void` could be modelled either with a `None` return, or a dummy
return variable with type `Tvoid`. Now it's always the latter.
Reviewed By: sblackshear, dulmarod
Differential Revision: D7832938
fbshipit-source-id: 0a403d1
Summary:
Now that we have the abstract state at the instruction level, we don't need to reexecute instructions during the checking phase and can just query the invariant map.
Depends on D7608526
Reviewed By: skcho
Differential Revision: D7775889
fbshipit-source-id: be17e2d
Summary:
Upgrade ocamlformat, and base which needs to be done in sync in order to build
ocamlformat, and the other deps can come for the ride.
Reviewed By: jvillard
Differential Revision: D7663537
fbshipit-source-id: 3e90970
Summary:
Now that everything can run at the same time and we have preanalyses, it can be quite hard to read debug sessions.
Here come session names!
Depends on D7607336
Reviewed By: sblackshear
Differential Revision: D7607481
fbshipit-source-id: 676af86
Summary:
So we can share stuff between analyses using the same CFG and node representation.
Depends on D7586302
Depends on D7586348
Depends on D7568701
Reviewed By: sblackshear
Differential Revision: D7586645
fbshipit-source-id: ed64b2c
Summary: This will facilitate accessing Inferbo abstract state at the instruction level from the Cost analysis
Reviewed By: ddino
Differential Revision: D7568701
fbshipit-source-id: 84ac648
Summary:
`Bottom` is only useful for unreachable code detection, which is already handled.
Let's not check `Bottom` states.
Depends on D7289084
Reviewed By: skcho
Differential Revision: D7289153
fbshipit-source-id: 8333ce7
Summary:
Show some `SymAssign`s (corresponding to parameters) in the trace.
Depends on D7194448
Reviewed By: skcho
Differential Revision: D7194479
fbshipit-source-id: 0deff6c
Summary: It collects array accesses from all sub expressions in commands.
Reviewed By: mbouaziz
Differential Revision: D7165098
fbshipit-source-id: 584dc80
Summary:
Because it matches calls (procnames and argument list) and because I will create a `Procname`-only one.
Depends on D7124847
Reviewed By: skcho
Differential Revision: D7124877
fbshipit-source-id: eca7c21
Summary:
At function calls, it copies a subset of heap memory that is newly
allocated by callees and is reachable from the return value.
Reviewed By: mbouaziz
Differential Revision: D7081425
fbshipit-source-id: 1ce777a
Summary:
The `may_last_field` boolean value in the `decl_sym_val` function presents that the location *may* (not *must*) be a flexible array member.
By the modular analysis nature, it is impossible to determine whether a given argument is a flexible array member or not---because of lack of calling context. For example, there are two function calls of `foo` below: (2) passes a flexible array member as an argument and (1) passes a non-flexible array, however it is hard to notice when analyzing the `foo` function.
```
struct T {
int c[1];
};
struct S {
struct T a;
struct T b;
};
void foo(struct T x) { ... }
void goo () {
struct S* x = (struct S*)malloc(sizeof(struct S) + 10 * sizeof(int));
foo(&(x->a)); // (1)
foo(&(x->b)); // (2)
}
```
We assume that any given arguments may stem from the last field of struct, i.e., flexible array member. (This is why `decl_sym_val` is called with `may_last_field:true` at the first time.) With some tests, we noticed that the assumption does not harm the analysis precision, because whether regarding a parameter as a flexible array member or not is about using a symbolic array size instead of a constant array size written in the type during the analysis of callee. Therefore still it can raise correct alarms if the actual parameter is given in its caller.
Reviewed By: mbouaziz
Differential Revision: D7081295
fbshipit-source-id: a4d57a0
Summary:
It supports flexible array member using the following heuristic:
- a memory for a class is allocated by `malloc(sizeof(C) + n * sizeof(T))` format
- the last field of the class is an array
- the static size of the last field is one, i.e., `T field_name[1]`
When allocating and initializing members of classes, it sets the size of flexible array to `n+1` if the above conditions are met.
Reviewed By: mbouaziz
Differential Revision: D7056291
fbshipit-source-id: 31c5868
Summary:
It abstracts the environments required in modeling functions and type
declarations as a record type.
Reviewed By: mbouaziz
Differential Revision: D7065996
fbshipit-source-id: b60cd3c
Summary:
It prunes abstract memories on `assert` commands.
Problem: Since the assert command is sometimes translated to two
sequential `if` statments, it was not able to prune the memory
precisely at `assert` commands in Inferbo---the pruned memory at the
first branch was joined before the second branch.
Solution: To avoid losing the pruning information at the first branch,
now, it records which locations are pruned at the first branch and
applies the same pruning at the next branch if they have
semantically the same condition.
Reviewed By: mbouaziz
Differential Revision: D6895919
fbshipit-source-id: 15ac1cb
Summary: The heuristics to determine the end of a block/procedure was too brittle, the new one ignores non significant instructions.
Reviewed By: jvillard
Differential Revision: D6845380
fbshipit-source-id: feab557
Summary:
Upgrade ocamlformat to 0.3, and (necessarily) base to v0.10.0.
- Fix accumulated mis-formatting
- Update opam.lock to unbreak clean build
- Update to base v0.10.0
- Update opam.lock for base
- Update offline opam repo
- Everyone should already have removed their ocamlformat pin
- ocamlformat 0.3 supports output to stdout natively
- bump version of ocamlformat
Reviewed By: jeremydubreil
Differential Revision: D6636741
fbshipit-source-id: 41a56a8
Summary:
Model for `folly::split` that handles the representation in the cpp model.
Depends on D6544992
Reviewed By: jvillard
Differential Revision: D6545006
fbshipit-source-id: 2b7a139
Summary: There was a back and forth conversion between `string` and `IssueType.t` which was not necessary.
Reviewed By: sblackshear
Differential Revision: D6562747
fbshipit-source-id: 70b57a2
Summary:
It seems that the abstraction instructions were not previously added the the CFG.
This is a functional changes to make sure that the abstraction state is always added. We can simplify the code later and just run this step before storing the CFG instead of after loading them.
Reviewed By: sblackshear, jvillard
Differential Revision: D6383672
fbshipit-source-id: cedcb8a
Summary:
justmovingthingsaround
Models need these functions, they have to be somewhere else.
The split might seem weird for now but will (hopefully) look more obvious in the following diff.
Reviewed By: skcho
Differential Revision: D6408322
fbshipit-source-id: c7e430f
Summary:
- Plug model checkers
- Add alloc size safety condition on alloc of negative, zero or big size
Reviewed By: sblackshear
Differential Revision: D6375144
fbshipit-source-id: bbea6f3
Summary:
A modeled function is not only an evaluator but also a checker, at least in Inferbo where both things happen in two passes.
This diff just prepares for it without generating new alarms.
Reviewed By: jvillard
Differential Revision: D6373051
fbshipit-source-id: 264696f
Summary:
Allow capturing function arguments.
Model functions don't have to match on a list any more.
Depends on D6347829
Reviewed By: jvillard
Differential Revision: D6350628
fbshipit-source-id: e88b758
Summary:
First steps of a dispatcher for C++ functions/methods overloads.
For now only used on Inferbo C modeled functions so most of the features are still unused.
Reviewed By: jvillard
Differential Revision: D6336088
fbshipit-source-id: ebd5b6f
Summary:
...so I just removed it
+ renamed `loc` of type `Location.t` to `location` to differentiate from `Loc.t` values
Reviewed By: jvillard
Differential Revision: D6358413
fbshipit-source-id: 2d3eba9
Summary:
Change ocamlformat installation procedure to use opam instead of
pinning.
Reformat all code with v0.2, which has a few improvements.
Reviewed By: jvillard
Differential Revision: D6292057
fbshipit-source-id: 759967f
Summary:
:
As we want to model many C++ methods, using a lot of matchers with `if / else if` will be tiring.
This diff introduces a dispatcher which is a nicer way to write the same thing.
No new model for now, just a refactoring.
Ideally we'd need a parser generator for C++ names...
Reviewed By: jvillard
Differential Revision: D6209234
fbshipit-source-id: 49fae5e
Summary:
vector::data returns a pointer to the first value of the vector.
- The size of the (array) pointer should be the same with the vector.
- The pointer should point to the same abstract value with the vector.
Reviewed By: mbouaziz
Differential Revision: D6196592
fbshipit-source-id: cc17096
Summary:
Install ocamlformat from github as part of `make devsetup`, and use it
for formatting OCaml (and jbuild) code.
Reviewed By: jvillard
Differential Revision: D6092464
fbshipit-source-id: 4ba0845
Summary:
A specific type of alias is added for the vector::empty() result and it is used at pruning.
Now, there are two types of aliases:
- "simple" alias: x=y
- "empty" alias: x=v.empty() and y=v.size
So, if x!=0, y is pruned by (y=0). Otherwise, i.e., x==0, y is pruned by (y>=1).
Reviewed By: mbouaziz
Differential Revision: D6004968
fbshipit-source-id: bb8d50d
Summary:
Move Inferbo safety conditions to their own file.
Split the old `Condition.t` to a condition together with a trace.
This will ease having: different kind of condition and several traces for the same condition (see following diff)
Reviewed By: jvillard
Differential Revision: D5942030
fbshipit-source-id: d74a612
Summary: A bottom interval in a safety condition doesn't make sense. Let's not allow it at all.
Reviewed By: skcho
Differential Revision: D5941552
fbshipit-source-id: 6bd2a65
Summary: Use `pp` functions until it needs to be turned into a string.
Reviewed By: jvillard
Differential Revision: D5941473
fbshipit-source-id: 87ca9df
Sungkeun Cho
Josh Berdine
Mehdi Bouaziz
Ezgi Çiçek
Nikos Gorogiannis
Jules Villard
Dino Distefano
Sam Blackshear
Jeremy Dubreil