Summary:
The configuration options for the analysis are used only/principally
in Control, they do not belong in the interface of domains. Also, the
definition of the used_globals type for the results of the used
globals pre-analysis belongs to the Domain_used_globals module.
Reviewed By: jvillard
Differential Revision: D27828752
fbshipit-source-id: e42de74e0
Summary:
Just reorder definitions to clarify that as_inlined_location is not
used in the rest of Stack.
Reviewed By: jvillard
Differential Revision: D27828755
fbshipit-source-id: 1436f1e6d
Summary: Preparation for allowing a choice among several scheduler strategies.
Reviewed By: jvillard
Differential Revision: D27828759
fbshipit-source-id: 63d6ec203
Summary:
The priority queue does not crucially depend on the type of
elements. This diff makes it parametric.
Reviewed By: jvillard
Differential Revision: D27828756
fbshipit-source-id: a7bfc4ee5
Summary:
When domain join operations are total, the control scheduler does not
need to handle the case where joining states is undefined. This leads
to some simplification, and in particular removed the need to expose a
remove operation for the scheduling queue.
Reviewed By: jvillard
Differential Revision: D27828761
fbshipit-source-id: b8cdd2eb6
Summary:
The only domain with a partial join is the lifting of a predicate
domain to a relation one, where the entry states are required to be
equal. This situation now indicates a programming error in the
analysis, rather than something that the domain should be responsible
for. Therefore this diff changes that check to an assertion and
simplifies the remaining join operations which are all total.
Reviewed By: jvillard
Differential Revision: D27828763
fbshipit-source-id: ec52ff741
Summary:
Mainly code cleanup. The only potential functional change is to
eliminate the test that a function returning with an empty stack is an
entry point, which should always hold anyhow.
Reviewed By: jvillard
Differential Revision: D27828749
fbshipit-source-id: 25124a568
Summary:
Mainly code simplification. The only functional change is to move the
test that a candidate entry-point function has no formals earlier,
with the result of avoiding failure if a function with an entry-point
name but with formals is encountered before an entry-point function
with no formals.
Reviewed By: jvillard
Differential Revision: D27828751
fbshipit-source-id: d5a832952
Summary:
There used to be a bug where recursive calls were not correctly
bounded. This is no longer needed, and this diff removes the
workaround that was added in D15577134 (881a4d10af) / 4cd3b62.
Reviewed By: jvillard
Differential Revision: D27828764
fbshipit-source-id: 80265a588
Summary:
Specifying that sledge should stop execution when the first report is
made via e.g. `sledge l a -t Stop` currently only works when debug
tracing is enabled. This diff fixes this so that `-t Stop` also works
for the release build.
Reviewed By: jvillard
Differential Revision: D27828753
fbshipit-source-id: dd7511ff1
Summary:
Currently all alarms are reported as "Invalid memory access", which is
not accurate for `abort` and hence assertion violations. This diff
adds an explicit type for alarms which distinguishes these two
cases. Further refinement is left for later.
Reviewed By: jvillard
Differential Revision: D27828754
fbshipit-source-id: 9c33f3c86
Summary:
The computation of common prefixes and suffixes was wrong. In
particular, the computation of the common suffix did not correctly
consider the common prefix. This manifested in case one entire
sequence is a suffix of the other.
Reviewed By: ngorogiannis
Differential Revision: D27564874
fbshipit-source-id: 267a75102
Summary:
Switch to a stronger but more expensive operation to check if a
symbolic heap is unsatisfiable.
Reviewed By: ngorogiannis
Differential Revision: D27564872
fbshipit-source-id: c8e306408
Summary:
`Typ.equivalent` relates types that denote the same sets of values in
the semantic model, such as pointers and integers of the appropriate
size. This diff strengthens the treatment of casts between such types
in the first-order solver by translating `(s)(t)e` to `e` for
equivalent types `s` and `t`.
These casts are usually simplified out of the bitcode produced by
clang. However, code using `_Atomic(...)` leads to `load atomic` llvm
instructions that, for some reason, cast pointers to i64 and back.
Reviewed By: ngorogiannis
Differential Revision: D27564881
fbshipit-source-id: 6138eb4f1
Summary:
When solving equations such as `α[o,l) = β`, the memory theory solver
computes a term to represent the length of α. This fails if α is a
variable (which might itself be equal to a sized term elsewhere in the
formula). This diff fixes such failures by generating a fresh variable
for the length in such situations.
Reviewed By: ngorogiannis
Differential Revision: D27564871
fbshipit-source-id: e5e066b77
Summary:
There are not too many cases where the function name is not enough to
disambiguate a trace message, but it is still perhaps more
approachable to include the module names as well.
Reviewed By: jvillard
Differential Revision: D27396914
fbshipit-source-id: ea4c8b44f
Summary:
Llair.Func.mk makes two passes over the CFG to resolve block parents,
jump destinations, and eliminate jumps to jumps. This is not
economical, but more importantly the current code mistakenly uses the
`retreating` metadata before it is set correctly. This diff combines
these passes into a single one, which also incorporates setting the
retreating field from Llair.Program.mk.
This avoids nontermination on code that contains immediate self-jumps
such as `L: goto L;` that LLVM 11 can now generate.
Reviewed By: jvillard
Differential Revision: D27262512
fbshipit-source-id: 0543ba669
Summary:
This warning (68) triggers when a function argument pattern depends on
mutable state, which prevents the remaining arguments from being
uncurried, causing additional closure allocations.
Reviewed By: jvillard
Differential Revision: D27188311
fbshipit-source-id: a43354e15
Summary:
It is possible for the filename of a source location to be the empty
string. Fpath.v asserts when passed an empty string.
Reviewed By: jvillard
Differential Revision: D27188304
fbshipit-source-id: a7d73444b
Summary:
The only difference between `program` and `identified` variables is
terminology, technically they are redundant.
Reviewed By: jvillard
Differential Revision: D26451308
fbshipit-source-id: eb4e7be43
Summary:
Negating the ids of program variables leads to inverting the order on
them. This is logically fine, the order is still a valid total order.
But it can lead to choosing younger variables as equality class
representatives over older variables, and thereby lead to more churn
as adding an equality is more likely to cause a change of
representative, and hence additional normalizing rewrites.
Reviewed By: jvillard
Differential Revision: D26451304
fbshipit-source-id: eb20d1901
Summary:
Theory.solved is a list of pairs of terms representing solved
equalities. The order of the pairs is very important, which is not
apparent from the type. This diff introduces an oriented_equality type
to make this more clear.
Reviewed By: jvillard
Differential Revision: D26451303
fbshipit-source-id: 56a49e601
Summary:
Generalize the existing find_or_add and find_and_remove operations to
find_update. Slightly simplify the interfaces of change, update,
find_or_add, and find_and_remove, reducing the gap to the natural
underlying functionality.
Reviewed By: jvillard
Differential Revision: D26451305
fbshipit-source-id: 89f67c84d
Summary:
The normalization and then extension of the carrier can be combined
into one pass. This weakens the property that this normalization needs
to achieve, which yields a small simplification, and combining the
passes is a minor optimization.
Reviewed By: jvillard
Differential Revision: D26400406
fbshipit-source-id: 8a3cbb2de
Summary:
An invariant of `And` and `Or` formulas is that they are flattened,
that is, `And` formulas do not have positive immediate subformulas of
form `And` nor negative immediate subformulas of form `Or`, and
similarly for `Or`. This invariant is ensured by the formula
constructors, which scan the immediate subformulas for cases that need
to be flattened.
When mapping over formulas, this repeated scanning is a performance
bottleneck. Most of the work of flattening is wasted since the input
formulas are necessarily already in flattened form, and the common
case is that the transformation preserves the flattened form. This
diff optimizes this case by detecting violations of flattening during
the transformation, performing the needed flattening, and avoiding the
general constructor that scans for flattening violations.
Reviewed By: jvillard
Differential Revision: D26338014
fbshipit-source-id: 9f15cca58
Summary:
Update the first-order equality solver for the sequence theory to
avoid searching the whole representation now that the super-term index
is maintained.
Reviewed By: jvillard
Differential Revision: D26338015
fbshipit-source-id: 24a9a19b6
Summary:
Similarly to terms, use the Comparar interface of Sets to defined
formulas using recursive types instead of recursive modules.
Reviewed By: jvillard
Differential Revision: D26250512
fbshipit-source-id: 84f0ae8c0
Summary: No functional change, just to make the interface easier to read
Reviewed By: jvillard
Differential Revision: D26250513
fbshipit-source-id: f3b07bccc
Summary:
Terms include Arithmetic terms, which are polynomials over terms
themselves. Monomials are represented as maps from
terms (multiplicative factors) to integers (their powers). Polynomials
are represented as maps from monomials (indeterminates) to
rationals (coefficients). In particular, terms are represented using
maps whose keys are terms themselves. This is currently implemented
using recursive modules.
This diff uses the Comparer-based interface of Maps to express this
cycle as recursive *types* rather than recursive *modules*, see the
very beginning of trm.ml. The rest of the changes are driven by the
need to expose the Arithmetic.t type at toplevel, outside the functor
that defines the arithmetic operations, and changes to stage the
definition of term and polynomial operations to remove unnecessary
recursion.
One might hope that these changes are just moving code around, but due
to how recursive modules are implemented, this refactoring is
motivated by performance profiling. In every cycle between recursive
modules, at least one of the modules must be "safe". A "safe" module
is one where all exposed values have function type. This allows the
compiler to initialize that module with functions that immediately
raise an exception, define the other modules using it, and then tie
the recursive knot by backpatching the safe module with the actual
functions at the end. This implementation works, but has the
consequence that the compiler must treat calls to functions of safe
recursive modules as indirect calls to unknown functions. This means
that they are not inlined or even called by symbol, and instead
calling them involves spilling registers if needed, loading their
address from memory, calling them by address, and restoring any
spilled registers. For operations like Trm.compare that are a handful
of instructions on the hot path, this is a significant
difference. Since terms are the keys of maps and sets in the core of
the first-order equality solver, those map operations are very very
hot.
Reviewed By: jvillard
Differential Revision: D26250533
fbshipit-source-id: f79334c68
Summary:
No functional change, apart from a minor change in invariant checking
for core constructors. Only to reduce diffs of upcoming changes.
Reviewed By: jvillard
Differential Revision: D26250518
fbshipit-source-id: a731e4fd6
Summary:
Inline functor applications, principally those involved in the
representation of (arithmetic) terms. This enables direct calls to
functions in the result of functor applications, instead of indirect
via an offset from the start of the module block resulting from the
functor appication. This also then enables further inlining
opportunities.
Reviewed By: jvillard
Differential Revision: D26338016
fbshipit-source-id: 27b770fa3
Josh Berdine