summaryrefslogtreecommitdiff
path: root/src/constant_fold.ml
AgeCommit message (Collapse)Author
2018-12-22Improve error messages and debuggingAlasdair Armstrong
Work on improving the formatting and quality of error messages When sail is invoked with sail -i, any type errors now drop the user down to the interactive prompt, with the interactive environment being the environment at the point the type error occurred, this means the typechecker state can be interactively queried in the interpreter to help diagnose type errors.
2018-12-13Fixing rationals in Sail interpreter and OCamlAlasdair Armstrong
2018-12-04Remove FES_Fexps constructorAlasdair Armstrong
This makes dealing with records and field expressions in Sail much nicer because the constructors are no longer stacked together like matryoshka dolls with unnecessary layers. Previously to get the fields of a record it would be either E_aux (E_record (FES_aux (FES_Fexps (fexps, _), _)), _) but now it is simply: E_aux (E_record fexps, _)
2018-11-28Allow folding constant expressions into single register readsAlasdair
Essentially all we have to do to make this work is introduce a member of the Value type, V_attempted_read <reg>, which is returned whenever we try to read a register value with allow_registers disabled. This defers the failure from reading the register to the point where the register value is used (simply because nothing knows how to deal with V_attempted_read). However, if V_attempted_read is returned directly as the result of evaluating an expression, then we can replace the expression with a single direct register read. This optimises some indirection in the ARM specification.
2018-11-23C backend improvementsAlasdair Armstrong
- Propagate types more accurately to improve optimization on ANF representation. - Add a generic optimization pass to remove redundant variables that simply alias other variables. - Modify Sail interactive mode, so it can compile a specification with the :compile command, view generated intermediate representation via the :ir <function> command, and step-through the IR with :exec <exp> (although this is very incomplete) - Introduce a third bitvector representation, between fast fixed-precision bitvectors, and variable length large bitvectors. The bitvector types are now from most efficient to least * CT_fbits for fixed precision, 64-bit or less bitvectors * CT_sbits for 64-bit or less, variable length bitvectors * CT_lbits for arbitrary variable length bitvectors - Support for generating C code using CT_sbits is currently incomplete, it just exists in the intermediate representation right now. - Include ctyp in AV_C_fragment, so we don't have to recompute it
2018-09-10Various fixesAlasdair Armstrong
C: Don't print usage message and quit when called with no arguments, as this is used for testing C output OCaml: Fix generation of datatypes with multiple type arguments OCaml: Generate P_cons pattern correctly C: Fix constant propagation to not propagate letbindings with type annotations. This behaviour could cause type errors due to how type variables are introduced. Now we only propagate letbindings when the type of the propagated variable is guaranteed to be the same as the inferred type of the binding. Tests: Add OCaml tests to the C end-to-end tests (which really shouldn't be in test/c/ any more, something like test/compile might be better). Currently some issues with reals there like interpreter. Tests: Rename list.sail -> list_test.sail because ocaml doesn't want to compile files called list.ml.
2018-08-23Fix interpreter after re-writer changeAlasdair Armstrong
Interpreter used a re-write (vector concat removal) that is dependent on the vector_string_to_bit_list rewriting pass. This fixes the interpreter to work without either vector concat removal, or turning bitstrings into vector literals like [bitzero, bitzero, bitone]. This has the upside of reducing the number of steps the interpreter needs for working with bitvectors so should improve interpreter performance. We also now test all the C compilation tests behave the same using the interpreter. Currently the real number tests fail due to limitations of Lem's rational library (this must be fixed in Lem). This required supporting configuration registers in the interpreter. As such the interpreter was refactored to more cleanly process registers when building an initial global state. The functions are also collected into the global state, which removes the need to search for them in the AST every time a function call happens. This should not only improve performance, but also removes the need to pass an AST into the interpretation functions.
2018-08-17Improve builtins testsAlasdair Armstrong
Test the builtin functions by compiling them to C, OCaml, and OCaml via Lem. Split up some of the longer builtin test programs to avoid stack overflows when compiling to OCaml, as 3000+ line long blocks can cause issues with some re-writing steps. Also test constant-folding with builtins (this should reduce the asserts in these files to assert true), and also test constant folding with the C compilation. Fix a bug whereby vectors with heap-allocated elements were not initialized correctly. Fix a bug caused by compiling and optimising empty vector literals. Fix an OCaml test case that broke due to the ref type being used. Now uses references to registers. Fix a bug where Sail would output big integers that lem can't parse. Checks if integer is between Int32.min_int and Int32.max_int and if not, use integerOfString to represent the integer. Really this should be fixed in Lem. Make the python test runner script the default for testing builtins and running the C compilation tests in test/run_tests.sh Add a ocaml_build_dir option that sets a custom build directory for OCaml. This is needed for running OCaml tests in parallel so the builds don't clobber one another.
2018-06-29Constant folding improvementsAlasdair
2018-06-06Fix a typo.Yao Li
2018-06-07Add a constant folding optimization passAlasdair