| Age | Commit message (Collapse) | Author |
|---|
|
For example:
bitfield cr : vector(8, dec, bit) = {
CR0 : 7 .. 4,
LT : 7,
CR1 : 3 .. 2,
CR2 : 1,
CR3 : 0,
}
The difference this creates a newtype wrapper around the vector type,
then generates getters and setters for all the fields once, rather
than having to handle this construct separately in every backend.
|
|
* Changed comment syntax to C-style /* */ and //
* References to registers and mutable variables are never created
implicitly - a reference to a register or variable R is now created
via the expression "ref R". References are assigned like "(*Y) = X",
with "(*ref R) = X" being equivalent to "R = X". Everything is always
explicit now, which simplifies the logic in the typechecker. There's
also now an invariant that every id directly in a LEXP is mutable,
which is actually required for our rewriter steps to be sound.
* More flexible syntax for L-expressions to better support wierd
power-idioms, some syntax sugar means that:
X.GET(a, b, c) ==> _mod_GET(X, a, b, c)
X->GET(a, b, c) ==> _mod_GET(ref X, a, b, c)
for setters, this can be combined with the (still somewhat poorly
named) LEXP_memory construct, such that:
X->SET(a, b, c) = Y ==> _mod_SET(ref X, a, b, c, Y)
Currently I use the _mod_ prefix for these 'modifier' functions, but
we could omit that a la rust.
* The register bits typedef construct no longer exists in the
typechecker. This construct never worked consistently between backends
and inc/dec vectors, and it can be easily replaced by structs with
fancy setters/getters if need be. One can also use custom type operators to mimic the syntax, i.e.
type operator ... ('n : Int) ('m : Int) = slice('n, 'm)
struct cr = {
CR0 : 32 ... 35,
/* 32 : LT; 33 : GT; 34 : EQ; 35 : SO; */
CR1 : 36 ... 39,
/* 36 : FX; 37 : FEX; 38 : VX; 39 : OX; */
CR2 : 40 ... 43,
CR3 : 44 ... 47,
CR4 : 48 ... 51,
CR5 : 52 ... 55,
CR6 : 56 ... 59,
CR7 : 60 ... 63,
}
This greatly simplifies a lot of the logic in the typechecker, as it
means that E_field is no longer ambiguously overloaded between records
and register bit typedefs. This also makes writing semantics for these
constructs much simpler.
|
|
Experimenting with porting riscv model to new typechecker
|
|
|
|
|
|
Requires linenoise library (opam install linenoise) for readline
support. Use 'make isail' to build sail with interactive
support. Plain 'make sail' should work as before with no additional
dependencies.
Use 'sail -i <commands>' to run sail interactively, e.g.
sail -new_parser -i test/ocaml/prelude.sail test/ocaml/trycatch/tc.sail
then try some commands for typechecking and evaluation
sail> :t main
sail> main ()
Doesn't use the lem interpreter right now, instead has a small
operational semantics in src/interpreter.ml, but this is not very
complete and will be changed/removed.
|
|
|
|
Also fix bug in mono analysis with generated variables
Breaks lots of typechecking tests because it generates unnecessary
equality tests on units (and the tests don't have generic equality),
which I'll fix next.
|
|
Alastair's test cases revealed that using regular ints causes issues
throughout sail, where all kinds of things can internally overflow in
edge cases. This either causes crashes (e.g. int_of_string fails for
big ints) or bizarre inexplicable behaviour. This patch switches the
sail AST to use big_int rather than int, and updates everything
accordingly.
This touches everything and there may be bugs where I mistranslated
things, and also n = m will still typecheck with big_ints but fail at
runtime (ocaml seems to have decided that static typing is unnecessary
for equality...), as it needs to be changed to eq_big_int.
I also got rid of the old unused ocaml backend while I was updating
things, so as to not have to fix it.
|
|
|
|
Need to map sail type annotations to interpreter type annotations in lem_ast ouput. This doesn't seem too hard.
|
|
This is the first step towards getting the interpreter working on this branch
|
|
|
|
There are several key changes here:
1) This commit allows for user defined operations in n-expressions
using the Nexp_app constructor. These operations are linked to
operators in the SMT solver, by using the smt extern when defining
operations. Notably, this allows integer division and modular
arithmetic to be used in types. This is best demonstrated with an
example:
infixl 7 /
infixl 7 %
val operator / = {
smt: "div",
ocaml: "quotient"
} : forall 'n 'm, 'm != 0. (atom('n), atom('m)) -> {'o, 'o = 'n / 'm. atom('o)}
val mod_atom = {
smt: "mod",
ocaml: "modulus"
} : forall 'n 'm. (atom('n), atom('m)) -> {'o, 'o = mod_atom('n, 'm). atom('o)}
val "print_int" : (string, int) -> unit
overload operator % = mod_atom
val main : unit -> unit
function main () = {
let 'm : {'x, 'x % 3 = 1. atom('x)} = 4;
let 'n = m / 3;
_prove(constraint(('m - 1) % 3 = 0));
_prove(constraint('n * 3 + 1 = 'm));
(* let x = 3 / 0; (* Will fail *) *)
print_int("n = ", n);
()
}
As can be seen, these nexp ops can be arbitrary user defined operators
and even operator overloading works (although there are some caveats).
This feature is very experimental, and some things won't work very
well once you use custom operators - notably unification. However,
this not necissarily a downside, because if restrict yourself to the
subset of sail types that correspond to liquid types, then there is
never a need to unify n-expressions. Looking further ahead, if we
switch to a liquid type system a la minisail, then we no longer need
to treat + - and * specially in n-expressions. So possible future
refactorings could involve collapsing the Nexp datatype.
2) The typechecker is stricter about valspecs (and other types) being
well-formed. This is a breaking change because previously we allowed
things like:
val f : atom('n) -> atom('n)
and now this must be
val f : forall 'n. atom('n) -> atom('n)
if we want to allow the first syntax, then initial-check should
desugar it this way - but it must be well-formed by the time it hits
the type-checker, otherwise it's not clear that we do the right
thing. Note we can actually have top-level type variables by using
top-level let bindings with P_var. There's a future line of
refactoring that would make it so that type variables can shadow each
other properly (we should do this) - currently they all have to have
unique names.
3) atom('n) is no longer syntactic sugar for range('n, 'n). The reason
why we want to do this is that if we wanted to be smart about what
sail operations can be translated into SMT operations at the type
level we care very much that they talk about atoms and not
ranges. Why? Because atom is the term level representation of a
specific type variable so it's clear how to map between term level
functions and type level functions, i.e. (atom('n) -> atom('n)) can be
reflected at the type level by a type level function with kind Int ->
Int, but the same is not true for range. Furthermore, both are
interdefinable as
atom('n) -> range('n, 'n)
range('n, 'm) -> {'o, 'n <= 'o <= 'm. atom('n)}
and I think the second is actually slightly more elegant. This change
*should* be backwards compatible, as the type-checker knows how to
convert from atom to ranges and unify them with each other, but there
may be bugs introduced here...
|
|
For example,
val test = { ocaml: "test_ocaml" } : unit -> unit
will only be external for OCaml. For other backends, it will have to be
defined.
|
|
For example:
val test = { ocaml: "test_ocaml", lem: "test_lem" } : unit -> unit
val main : unit -> unit
function main () = {
test ();
}
for a backend not explicitly provided, the extern name would be simply
"test" in this case, i.e. the string version of the id.
Also fixed some bugs in the ocaml backend.
|
|
|
|
Fix until loop not being counted as sugar
|
|
|
|
but problem with aux introduced 'a type variables
|
|
and syntax changes
|
|
|
|
node for passing around encapsulated evaluated values; change Interp.to_exp to now just wrap values in this node
|
|
|
|
|
|
|
|
|
|
|
|
|
|
fix Makefile clean
|
|
|
|
|
|
math symbols. This breaks the l2.pdf build in language/ (for the moment).
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Conflicts:
language/manual.pdf
|
|
|
|
|
|
|
|
|
|
|
|
Minor updates to README, still in progress
|
|
|
|
change to printing
|
|
This reverts commit d836ac35d82311ae7522937b8b01c140f8616b97.
|
|
|
