summaryrefslogtreecommitdiff
path: root/src/rewrites.ml
AgeCommit message (Collapse)Author
2019-11-06Allow specifying specific fields of a register as constant with ↵Alasdair Armstrong
:fixed_registers command
2019-11-06Add toplevel commands to fix specific register values and simply spec ↵Alasdair Armstrong
accordingly
2019-08-13Coq: fix non-exhaustive pattern match failure in riscv duopodBrian Campbell
2019-08-02Fix all warnings (except for two lem warnings)Alasdair Armstrong
Remove P_record as it's never been implemented in parser/typechecker/rewriter, and is not likely to be. This also means we can get rid of some ugliness with the fpat and mfpat types. Stubs for P_or and P_not are left as they still may get added to ASL and we might want to support them, although there are good reasons to keep our patterns simple. The lem warning for while -> while0 for ocaml doesn't matter because it's only used in lem, and the 32-bit number warning is just noise.
2019-08-01Merge branch 'sail2' into separate_bvAlasdair Armstrong
2019-08-01Merge remote-tracking branch 'origin/rv_duopod_fix' into sail2Alasdair Armstrong
Fixes #53
2019-07-16Fix all remaining tests for this branchAlasdair
2019-07-16Merge remote-tracking branch 'origin/sail2' into separate_bvAlasdair Armstrong
2019-07-11Make sure constant folding won't fold external definitions that also have ↵Alasdair Armstrong
sail definitions Definitions can be made external on a per-backend basis, so we need to make sure constant folding doesn't inline external functions that have sail definitions for backends other than the ones we are currently targetting
2019-06-30Fix bug with toplevel pattern in RISC-V duopodAlasdair
Do this by making sure that generic pattern literal re-writing gets applied to top-level function clauses. This requires re-ordering the rewrites for most backends otherwise they break, which hopefully wo anything. After doing this re-ordering I had to turn off casting when rewriting bitvector patterns, otherwise insane things can happen.
2019-06-19Rewriting improvements for monomorphic aarch64_smallBrian Campbell
- allow disjoint_pat to be used on patterns that have just been introduced by the rewrite without rechecking - don't rebuild the matched expression in the generated fallthrough case (or any wildcard fall-through) - it may be dead code and generate badly typed Lem - update the type environment passed to rewrites whenever type checking is performed; stale information broke some rewrites
2019-06-18Fix handling of E_internal_plet in rewriteThomas Bauereiss
2019-06-13Fix some bugs in Lem rewriterThomas Bauereiss
A missing type annotation in rewrite_guarded_clauses caused a crash in some cases. Also fix an effect propagation bug in rewrite_letbind_effects.
2019-06-12Handle partial matches in guarded pattern rewriteThomas Bauereiss
Add a fallthrough case that fails to potentially partial pattern matches. This also helps to preserve any guard in the final match case, which might be needed for flow typing (see the discussion on issue #51). TODO: Merge with the MakeExhaustive rewrite, which currently does not support guarded patterns.
2019-06-10Add well-formedness check for type schemes in valspecs.Brian Campbell
Fixes #47. Also adjust the nexp substitution so that the error message points to a useful location, and replace the empty environment with the initial environment in a few functions that do type checking to ensure that the prover is set up (which may be needed for the wf check).
2019-06-06Add an option to pre-compile the axiomatic model for SMTAlasdair Armstrong
2019-06-04Merge branch 'sail2' into separate_bvAlasdair Armstrong
2019-06-04Remove unused AST constructorAlasdair Armstrong
Clean up ott grammar a bit
2019-06-04SMT: Add a fuzzing tool for the SMT builtinsAlasdair Armstrong
2019-06-03Coq: support non-exhaustive pattern rewrite for exception handlingBrian Campbell
2019-05-17Get all Lem tests working with separate bitvector typeAlasdair Armstrong
2019-05-17Experiment with making vector and bitvector distinct typesAlasdair Armstrong
Only change that should be needed for 99.9% of uses is to change vector('n, 'ord, bit) to bitvector('n, 'ord), and adding $ifndef FEATURE_BITVECTOR_TYPE type bitvector('n, dec) = vector('n, dec, bit) $endif for to support any Sail before this Currently I have all C, Typechecking, and SMT tests passing, as well as the RISC-V spec building OCaml and C completely unmodified.
2019-05-1594f445 introduced a new name for _ref_deref, add it to the effect rewritingBrian Campbell
2019-04-27Merge branch 'sail2' into smt_experimentsAlasdair
2019-04-20Fix: Reduce constant-fold time for ARM from 20min+ to 10sAlasdair Armstrong
With the new interpreter changes computing the initial state for the interpreter does some significant work. The existing code was re-computing the initial state for every subexpression in the specification (not even just the ones due to be constant-folded away). Now we just compute the initial state once and use it for all constant folds. Also reduce the time taken for the simple_assignments rewrite from 20s to under 1s for ARMv8.5, by skipping l-expressions that are already in the simplest form.
2019-04-17Coq: support pure loops with termination measuresBrian Campbell
2019-04-15Merge branch 'sail2' of github.com:rems-project/sail into sail2Jon French
2019-04-15Merge branch 'sail2' into rmem_interpreterJon French
2019-04-15Basic loop termination measures for CoqBrian Campbell
Currently only supports pure termination measures for loops with effects. The user syntax uses separate termination measure declarations, as in the previous recursive termination measures, which are rewritten into the loop AST nodes before type checking (because it would be rather difficult to calculate the correct environment to type check the separate declaration in).
2019-04-13SMT: Add count_leading_zeros and more builtinsAlasdair
2019-04-11SMT: Add property and counterexample directiveAlasdair Armstrong
Rather than generating SMT from a function called check_sat, now find any function with a $property directive and generate SMT for it, e.g. $property function prop_cap_round_trip(cap: bits(128)) -> bool = { let cap_rt = capToBits(capBitsToCapability(true, cap)); cap == cap_rt } $property function prop_base_lteq_top(capbits: bits(128)) -> bool = { let c = capBitsToCapability(true, capbits); let (base, top) = getCapBounds(c); let e = unsigned(c.E); e >= 51 | base <= top } The file property.ml has a function for gathering all the properties in a file, as well as a rewrite-pass for properties with type quantifiers, which allows us to handle properties like function prop forall 'n, 'n <= 100. (bv: bits('n)) -> bool = exp by rewriting to (conceptually) function prop(bv: bits(MAX_BIT_WIDTH)) -> bool = if length(bv) > 100 then true else exp The function return is now automatically negated (i.e. always true = unsat, sometimes false = sat), which makes sense for quickcheck-type properties.
2019-04-10Coq: tweak measure rewrites slightlyBrian Campbell
Allows a quick hack where you can give a termination limit rather than a proper measure for functions with awkward termination properties.
2019-04-09SMT: Experimental Jib->SMT translationAlasdair Armstrong
Currently only works with CVC4, test cases are in test/smt. Can prove that RISC-V add instruction actually adds values in registers and that's about it for now.
2019-04-06Various bugfixes and improvementsAlasdair
- Rename DeIid to Operator. It corresponds to operator <string> in the syntax. The previous name is from when it was called deinfix in sail1. - Removed things that weren't actually common from pretty_print_common.ml, e.g. printing identifiers is backend specific. The doc_id function here was only used for a very specific use case in pretty_print_lem, so I simplified it and renamed it to doc_sia_id, as it is always used for a SIA.Id whatever that is. - There is some support for anonymous records in constructors, e.g. union Foo ('a : Type) = { MkFoo : { field1 : 'a, field2 : int } } somewhat similar to the enum syntax in Rust. I'm not sure when this was added, but there were a few odd things about it. It was desugared in the preprocessor, rather than initial_check, and the desugaring generated incorrect code for polymorphic anonymous records as above. I moved the code to initial_check, so the pre-processor now just deals with pre-processor things and not generating types, and I fixed the code to work with polymorphic types. This revealed some issues in the C backend w.r.t. polymorphic structs, which is the bulk of this commit. I also added some tests for this feature. - OCaml backend can now generate a valid string_of function for polymorphic structs, previously this would cause the ocaml to fail to compile. - Some cleanup in the Sail ott definition - Add support for E_var in interpreter previously this would just cause the interpreter to fail
2019-04-05Coq: termination measures for mutually recursive functionsBrian Campbell
2019-03-27Interactive: Refactor sail.ml some moreAlasdair Armstrong
Separate calling the rewriter from the backend-specific parts of sail.ml
2019-03-27Interactive: Refactor sail.mlAlasdair Armstrong
Rather than having a separate variable for each backend X, opt_print_X, just have a single variable opt_print_target, where target contains a string option, such as `Some "lem"` or `Some "ocaml"`, then we have a function target that takes that string and invokes the appropriate backend, so the main function in sail.ml goes from being a giant if-then-else block to a single call to target !opt_target ast env This allows us to implement a :compile <target> command in the interactive toplevel Also implement a :rewrites <target> command which performs all the rewrites for a specific target, so rather than doing e.g. > sail -c -O -o out $FILES one could instead interactively do > sail -i :option -undefined_gen :load $FILES :option -O :option -o out :rewrites c :compile c :quit for the same result. To support this the behavior of the interactive mode has changed slightly. It no longer performs any rewrites at all, so a :rewrites interpreter is currently needed to interpret functions in the interactive toplevel, nor does it automatically set any other flags, so -undefined_gen is needed in this case, which is usually implied by the -c flag.
2019-03-27Rewriter: Finish refactoring rewrite sequencesAlasdair Armstrong
2019-03-26Rewriter: Expose rewrite passes to interactive modeAlasdair Armstrong
Rather than each rewrite being an opaque function, with separate lists of rewrites for each backend, instead put all the rewrites into a single list then have each backend define which of those rewrites it wants to use and in what order. For example, rather than having let rewrite_defs_ocaml = [ ... ("rewrite_undefined", rewrite_undefined_if_gen false); ... ] we would now have let all_rewrites = [ ... ("undefined", Bool_rewriter (fun b -> Basic_rewriter (rewrite_undefined_if_gen b))); ... ] let rewriters_ocaml = [ ... ("undefined", [Bool_arg false]); ... ] let rewrite_defs_ocaml = List.map (fun (name, args) -> (name, instantiate_rewrite (List.assoc name all_rewrites) args)) rewriters_ocaml This means we can introspect on the arguments required for each rewrite, allowing a :rewrite command in the interactive mode which can parse the arguments required for each rewrite, so we can invoke the above rewrite as sail> :rewrite undefined false with completion for the rewrite name based on all_rewrites, and hints for any arguments. The idea behind this is if we want to generate a very custom slice of a specification, we can set it up as a sequence of interpreter commands, e.g. ... :rewrite split execute :slice_roots execute_LOAD :slice_cuts rX wX :slice :rewrite tuple_assignments ... where we slice a spec just after splitting the execute function. This should help in avoiding an endless proliferation of additional options and flags on the command line.
2019-03-15Various monomorphisation tweaks and fixesThomas Bauereiss
2019-03-15Add a rewriting pass for constant propagation in mutrecsThomas Bauereiss
Propagating constants into mutually recursive calls and removing dead branches might break mutually recursive cycles. Also make constant propagation use the existing interpreter-based constant folding to evaluate function calls with only constant arguments (as opposed to a mixture of inlining and hard-coded rewrite rules).
2019-03-14Merge branch 'sail2' into rmem_interpreterJon French
2019-03-11Improve ocamldoc commentsAlasdair Armstrong
Check in a slightly nicer stylesheet for OCamldoc generated documentation in etc. Most just add a maximum width and increase the font size because the default looks absolutely terrible on high-DPI monitors. Move val_spec_ids out of initial_check and into ast_util where it probably belongs. Rename some functions in util.ml to better match the OCaml stdlib.
2019-03-08Rewriter: Cleanup old sizeof rewritesAlasdair Armstrong
Shouldn't affect anything as this is done by the typechecker now. Also remove some unfinished tracing code from c_backend.ml
2019-03-07Also remove impossible if-branchesThomas Bauereiss
2019-03-07Add a rewrite to remove impossible cases on integer literalsBrian Campbell
(e.g., for the dual 32/64 bit RISC-V model) Apply this rewrite in Coq backend.
2019-03-04Fix aarch64_small test XML for jenkinsAlasdair Armstrong
Rename rewrite_split_fun_constr_pats to rewrite_split_fun_ctor_pats as constr is commonly used as an abbreviation for constraint rather than constructor, and add a more descriptive comment.
2019-03-04Fix execute splitting to work when constructors have constraints.Alasdair Armstrong
Previously any constraints on constructors were just outright dropped when splitting the execute function in Lem generation. Now we get the constraints and type signature for each execute clause from the type given by Env.get_union_constructor, rather than by inferring the type of the pattern in each function clause. Currently this can still fail in the case where we have union U('x: Int), C1('x) = { ctor: {'y. C2('x, 'y), T('x, 'y)} } and val execute : forall 'z, C3('z). U('z) -> unit when C3 implies C1, and the body of an excute clause relies on the fact that C3 is stronger than C1, as each split function execute_ctor is only guaranteed to be constrained by some subset of C1. This seems unlikely to happen in practice though. Also fix a bug when binding P as int('T) against int('T) and similar cases, where the new type variable would cause the old type variable to become shadowed, but the constraint that the bound type variable and the old type variable are equal would not take this into account.
2019-03-04Merge branch 'sail2' into rmem_interpreterJon French
2019-02-27Tweaks to C compilation to make it more usable for embedding into other programsAlasdair Armstrong
Can now set a prefix for generated C functions with -c_prefix so -c_prefix sail_ would give sail_execute_CGetPerm over zexecute_CGetPerm. We still have to use our standard name-mangling scheme to avoid possible collisions within the name. Can build C that doesn't expect the standard runtime, which leaves operations like read_memory, write_memory etc to be stubbed in by another C program including the generated Sail. Things like letbindings are still an issue because we rely on a very small runtime to initialize global letbindings and similar. -c_separate_execute splits the execute function apart in the generated C