Commit Graph

13 Commits

Author SHA1 Message Date
Anand Krishnamoorthi
87f22a79ca fix: harden regex builtins with compiled-size limit (#705)
Add a 100KB cap on compiled regex NFA size via RegexBuilder::size_limit()
to block patterns that blow up in memory or CPU. Regex compilation now
goes through a single helper (compile_regex_for_builtin) so the limit
is enforced consistently across all regex builtins.

While doing this, found and fixed a pre-existing bug: resource-limit
errors (time, memory, instruction count) raised inside builtins were
quietly swallowed to Undefined when strict_builtin_errors was off
(the default). This is a problem because `not regex.match(...)` would
see Undefined and flip to true -- silently wrong. The same issue now
applies to the new regex size limit.

Fixed by teaching the three error-absorption paths (interpreter builtin
call, RVM builtin dispatch, and RVM rule-execution loop) to recognize
LimitError and let it propagate instead of eating it.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
2026-05-04 15:20:29 -05:00
Mark Birger
83ce8c3580 Fix RVM evaluation of default-only rules (#664)
Default-only rules (e.g., `default deny := true` with no conditional body)
returned Undefined in the RVM instead of the default value.

Compiler:
- compute_rule_type: return Complete when rule exists only in default_rules map
- compile_worklist_rule: emit register slots and data-tree entries for
  default-only rules (else branch)

VM:
- execute_call_rule_common + execute_call_rule_suspendable: check
  default_literal_index before returning Undefined when definitions is empty

Tests:
- 3 new RVM cases (default_rules.yaml): bool, object, entry-point
- 3 new interpreter cases (default/basic.yaml): matching coverage

Co-authored-by: Mark Birger <markbirger@microsoft.com>
2026-04-07 11:38:50 -05:00
Anand Krishnamoorthi
83891d7782 RVM compiler & runtime optimizations: caching, instruction fusion, constant hoisting, and correctness fixes (#626)
* perf!: add LRU caches for compiled regex and glob patterns

Add bounded LRU caches for compiled regex and glob patterns used by
Rego builtins, avoiding repeated recompilation of the same patterns
during policy evaluation.

New `cache` feature (included in `full-opa` and `opa-no-std`) backed by
the `lru` crate (no_std compatible) with `spin::Mutex` for thread safety.

- `src/cache.rs`: generic `LruCache<V>` wrapper, global `REGEX_CACHE`
  (default capacity 256) and `GLOB_CACHE` (default capacity 128)
- `src/builtins/regex.rs`: all regex builtins route through the cache
- `src/builtins/glob.rs`: glob.match routes through the cache
- Public API: `regorus::cache::{Config, configure, clear}`

Compilation costs avoided per cache hit:
  regex  10-55 µs  (simple to complex patterns)
  glob   10-12 µs
  LRU hit   ~10 ns

BREAKING CHANGE: new `cache` Cargo feature added to `full-opa` and
`opa-no-std` feature sets; adds `lru` as a dependency.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* perf(vm): amortize per-instruction memory and time limit checks

Deduplicate per-instruction memory_check calls by hoisting them to the
main dispatch loop, and amortize monotonic_now() syscalls in the
execution timer by checking elapsed time every N instructions instead
of on every tick.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* fix(vm): correct object membership to check values only, not keys

The Contains instruction for objects was checking both keys and values:

    object_fields.contains_key(v) || object_fields.values().any(|v| ...)

Per the Rego specification, `x in obj` tests whether x is a VALUE of
the object, not a key. The two-argument form `k, v in obj` is needed
to access keys. The interpreter already implemented this correctly
(values-only scan), but the RVM had the extra contains_key() check
which would incorrectly return true when the search value happened to
match a key name.

Remove the contains_key() branch so the behavior matches the interpreter
and the Rego spec. Add two regression tests:
- object_membership_checks_values_not_keys: "foo" in {"foo": "bar"}
  must be false (key, not a value)
- object_membership_finds_value: "bar" in {"foo": "bar"} must be true

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* perf(compiler): hoist all-constant collection literals to the literal table

When an array, set, or object literal consists entirely of compile-time
constant expressions (numbers, strings, bools, null, and nested constant
collections), the compiler now evaluates them at compile time and emits a
single Load instruction from the literal table instead of generating
per-element instructions at runtime.

Previously, a Rego expression like `x in [1, 2, 3]` would emit
ArrayCreate + three Load + three ArrayAppend instructions, allocating a
new Vec and Rc on every evaluation. With this change, the entire array
is built once during compilation and loaded as a single constant.

This optimization applies to all three collection types:
- Array literals: avoids ArrayCreate + N x (Load + ArrayAppend)
- Set literals: avoids SetCreate + N x (Load + SetAdd)
- Object literals: avoids ObjectCreate + N x (Load + Load + ObjectInsert)

The implementation adds a try_eval_const() helper that recursively
evaluates an AST expression as a constant Value, returning None if any
sub-expression is non-constant. Each compile method for collection
literals attempts the all-constant fast path first and falls through to
the existing instruction-by-instruction codegen otherwise.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* perf(compiler): fuse Eq + AssertCondition into AssertEq instruction

Add a new `AssertEq { left, right }` instruction that combines equality
comparison and condition assertion into a single operation. This replaces
the previous two-instruction pattern of `Eq { dest, left, right }` followed
by `AssertCondition { condition: dest }`, saving one instruction and one
register per equality assertion.

The fused instruction checks two registers for equality and directly calls
handle_condition with the result, avoiding the intermediate boolean
register entirely. If either operand is undefined or the values differ,
the condition fails and the rule/loop backtracks.

The optimization applies to four destructuring sites:
- EqualityCheck (assignment re-binding with `x = expr; x = expr`)
- EqualityExpr (destructuring against an expression)
- EqualityValue (destructuring against a literal value)
- assert_array_length (array length validation in destructuring)

In soft_assert_mode the compiler still emits the original Eq instruction
since the boolean result register is needed by callers.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* perf(compiler): fuse Not + AssertCondition into AssertNot instruction

Add a new `AssertNot { operand }` instruction that combines logical
negation and condition assertion into a single operation. This replaces
the previous two-instruction pattern of `Not { dest, operand }` followed
by `AssertCondition { condition: dest }`, saving one instruction and one
register allocation.

The fused instruction checks the operand register and passes the
condition if the value is false or undefined (per Rego semantics where
`not expr` succeeds when the expression has no results or is false),
and fails the condition if the value is true or any non-boolean truthy
value.

This was the only emission site for the Not+AssertCondition pair,
occurring in the compilation of `Literal::NotExpr` statements.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* perf(vm): early exit for same-value multi-definition rules

When a rule has multiple definitions that all produce the same value
(e.g. implicit true, or identical literal), set early_exit_on_first_success
on RuleInfo so the VM can stop after the first successful definition.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* feat!: expose cache configuration API to all language bindings

Add `set_cache_config` and `clear_cache` functions to every binding
so callers can tune or reset the global regex/glob pattern caches
introduced in the cache feature.

Bindings updated:
- FFI (C): `regorus_set_cache_config`, `regorus_clear_cache`
- C++ header: free functions `regorus::set_cache_config`, `regorus::clear_cache`
- Python: module-level `set_cache_config(*, regex, glob)`, `clear_cache()`
- Java: static methods on new `CacheConfig` class
- Go: package-level `SetCacheConfig`, `ClearCache`
- Ruby: module functions `Regorus.set_cache_config`, `Regorus.clear_cache`
- WASM: free functions `setCacheConfig`, `clearCache`
- C#: static methods `Engine.SetCacheConfig`, `Engine.ClearCache`

BREAKING CHANGE: Bump SERIALIZATION_VERSION from 4 to 5 due to new
AssertEq and AssertNot instruction variants added in the instruction
fusion commits. Programs serialized with version 5 cannot be loaded
by older versions of regorus.

* fix: address PR review feedback

Cache subsystem:
- Gate REGEX_CACHE and related imports behind #[cfg(feature = "regex")]
  so that building with --features cache without regex compiles correctly.
- Gate LruCache struct behind #[cfg(any(feature = "regex", feature = "glob"))].
- Add Config::MAX_CAPACITY (2^16) hard upper bound; clamp values in
  configure() to prevent unbounded cache growth.
- Use parking_lot::Mutex for std builds and spin::Mutex for no_std to
  avoid CPU spinning under contention in tight regex/glob eval loops.
- Narrow lock scopes in regex/glob builtins: release the mutex before
  compiling a pattern, then re-acquire to insert.

Java JNI binding:
- Fix cache config overflow: negative jlong values now saturate to 0
  and positive overflow saturates to usize::MAX (then clamped by
  MAX_CAPACITY) instead of silently disabling the cache.
- Gate JNI cache config/clear functions behind #[cfg(feature = "cache")].

Compiler:
- Refactor static_value_of_expr to delegate to try_eval_const,
  gaining support for negated numbers and constant collections.
- Make try_eval_const pub(in crate::languages::rego::compiler) and
  re-export through expressions.rs.
- Handle Expr::UnaryExpr with numeric literals in try_eval_const so
  collections containing negated numbers (e.g. [-1, 2]) are hoisted.

VM correctness:
- Fix Not instruction to follow Rego semantics: not expr yields
  true when expr is undefined or false, false for any other defined
  value (including non-booleans) -- no longer errors on non-boolean
  operands.
- Add enforce_memory_check() call at execute_suspendable_entry to
  ensure memory limits are checked before the first instruction.
- Update AssertNot listing comment to "exit if any defined truthy
  value" to match actual VM behaviour.
- Add doc comment on Not instruction clarifying Rego negation
  semantics.

Bindings:
- Fix C++ header indentation for set_cache_config / clear_cache.
- Propagate Cargo.lock parking_lot addition across ffi, java, python,
  and wasm binding lockfiles.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

---------

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-03-23 21:00:51 -05:00
Anand Krishnamoorthi
3f7a5496dc feat(bindings)!: add RVM/Program support across FFI and language bindings (#565)
- FFI: add RVM/Program APIs, execution state accessors, HostAwait handling, and buffer/result helpers in rvm.rs, common.rs, engine.rs.
- Compiler: emit HostAwait for __builtin_host_await in function_calls.rs.
- RVM tests: add HostAwait regression cases and extend harness for suspend/resume responses in host_await.yaml and mod.rs.
- C/C++: add RVM tests/examples and wrapper updates in rvm_tests.c, rvm_tests.cpp, regorus.hpp, plus CMake wiring.
- C#: add Program/Rvm bindings, SafeHandle/PInvoke, tests, and example usage in Regorus, RvmProgramTests.cs, Program.cs, and README updates.
- Go: add Program/Rvm bindings, tests, and examples in rvm.go, rvm_test.go, main.go.
- Java: add Program/Rvm bindings, JNI glue, and examples in lib.rs, regorus, Test.java.
- Python: add Program/Rvm bindings and examples in lib.rs, test.py.
- WASM: add Program/Rvm bindings and examples in lib.rs, test.js.
- Tooling: wire binding tests in xtask and ignore generated Java artifacts in .gitignore.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-30 23:55:31 +05:30
Anand Krishnamoorthi
9426b2ec02 fix: Imports without a name binding (#543)
Handle imports that don't use the `as` clause to create a binding.
These imports are bound to the last identifier in the imported path.

Fix both interpreter and compiler.
Add tests.

fixes #541

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-15 03:57:52 +05:30
Anand Krishnamoorthi
9fa8036ce4 feat: Implement Rego else block compilation
- teach the Rego compiler to compile else chains correctly
- test suite

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-16 12:03:03 -06:00
Anand Krishnamoorthi
a514e8da83 fix: Implement RVM set ops correctly
- treat set subtraction in RVM the same as the interpreter by supporting
  Value::Set operands in sub_values
- emit internal-only builtin names for set union/intersection and register
  handlers so compiled bytecode resolves without exposing new Rego builtins
- add regression coverage for literal set difference/intersection
  (x/y from failure.rego) in tests/rvm/rego/cases/sets.yaml

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-16 12:03:02 -06:00
Anand Krishnamoorthi
bedf667adc feat: Handle literal comparisons that use = and comprehensions without loops
- emit AssertCondition for equality-only assignment plans (outside soft-assert mode) so rules like `0 = 1` fail under the VM just like the interpreter
- let comprehension bodies consume assertion failures by advancing or exiting their iteration context, both in run-to-completion and suspendable execution

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-03 13:34:14 -06:00
Anand Krishnamoorthi
8269968c4a feat: Handle computed reference roots in RVM compiler
Allow compile_chained_ref to fall back to “evaluate root expression → chain access”
so literal arrays, comprehensions, and other computed roots no longer raise NotSimpleReferenceChain.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-03 13:34:14 -06:00
Anand Krishnamoorthi
e3d23766ae feat: Ensure RVM caches deterministic builtins
Mirror interpreter implementation:
- use builtins::must_cache to determine whether builtin must be cached.
- reuse cached value when applicable
- clear the VM’s builtin cache whenever execution state resets to avoid leaking values across runs
- add a YAML regression for rand.intn set comprehensions and re-enable the rand cases in the OPA test suite

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-03 13:34:14 -06:00
Anand Krishnamoorthi
b7b3d3ec87 feat: Soft-assert mode for builtin out-params under not
- Add a scoped soft_assert_mode to the compiler so `not` statements compile their subexpressions without emitting hard AssertCondition/AssertNotUndefined instructions.
- Teach binding-plan application to return an optional result register; equality plans now yield a boolean in soft mode, allowing not abs(-5 , 3) to succeed instead of aborting.
- Update function-call, loop, and rule plumbing to consume the new binding-plan outcome, including copying the produced register when an out-parameter equality is used.
- Trim the OPA TODO list to the remaining troublesome folders.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-02 15:27:43 -06:00
Anand Krishnamoorthi
30bd134a0b fix: Handle builtin out-parameter calls in RVM compiler
- Teach the hoister/destructuring planner to respect parent scope when building binding plans for extra arguments, so already-bound vars yield equality checks.
- Update the compiler’s function-call path to drop the trailing out-argument, run its binding plan after the call, and share call-target resolution logic.
- Add regression suites for builtin and user-defined out-parameter scenarios plus align the CLI example output when RVM returns undefined.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-02 13:29:12 -06:00
Anand Krishnamoorthi
a3a20a1235 feat!: Rego -> RVM Compiler and extensive testsuite (#506)
# RVM compiler test cases

Coverage:
- arithmetic
- arrays
- chained lookups
- comparisons
- comprehensions
- default rules
- destructuring
- function rules
- loops/quantifiers
- multiple entrypoints
- objects/sets
- variables
- negative/edge scenarios such as data/rule conflicts
- virtual data lookups
- etc

 # Modify interpreter and compiled policy for RVM Compilation

- Interpreter::eval_default_rule_for_compiler:
   evaluates a named default rule in isolation - allows compiler to emit a constant value instead of instructions
   for the default value

#  feat: Rego Compiler Scaffolding

- Introduce the rego::compiler module surface and entry point wiring
- Add the core compiler concepts:
  - register allocator
  - scope tracking
  - literal/builtin tables
  - rule worklists
  - instruction emit helpers
  - compiler-specific error types
  - context structs for rules, comprehensions, and loops to support later lowering passes.

# feat: Compile Rules/Queries

- add compiler::compile_from_policy workflow plus rule worklist, entry-point wiring, and recursion checks
- implement query lowering:
  - scheduling-aware statement ordering
  - loop hoisting
  - “every/some” semantics
  - context yields
  -  literal assertions
- finalize Program construction

# feat: Expression Lowering

- add compile_rego_expr and helpers to translate every AST expression into RVM instructions,
- interop with binding plans, comprehensions, and membership checks.
- implement collection literal builders (ArrayCreate, SetCreate, ObjectCreate)
  - dedupe literal keys and handle mixed literal/dynamic fields via instruction data blocks.
- operations:
  - arithmetic/boolean/bin operators
  - membership
  - unary minus
  - set unions/intersections
  - etc
- user-defined and builtin function calls
- reference handling
  - analyse chained refs
  - distinguishe data/input/local roots
  - perform rule dispatch or virtual document lookups
  - emits optimized Index/ChainedIndex instructions.

# feat: Comprehensions & Loops

- shared comprehension emitter
 - wraps array/set/object comprehensions with ComprehensionBegin/End
 - context management
- loop lowering utilities
 - read hoisting metadata
 - emit LoopStart/LoopNext
 - some in lowering
 - every quantifiers
 - index iteration
 - propagate binding plans into stored registers so downstream statements see bound variables.

# feat: Destructuring Lowering

- destructuring planner integration
 - assignment/parameter/loop bindings use hoisted plans instead of re-walking ASTs.
- handle :=, =, wildcard matches, and equality
 - evaluate RHS
 - applying destructuring plans
 - emit assert condition as needed
- support nested array/object destructuring, dynamic keys, and some ... in forms

# test: Shared Testing + RVM Suites

- move YAML test helpers into test_utils.rs and re-export via common.rs for use by interpreter and vm test suites
- comprehensive compiler test suite
  - compiles policies with the new Rego→RVM compiler
  - runs them through RegoVM
  - compares against interpreter behavior
  - supports multiple entry points
  - provides assembly listings
  - filterable YAML suites.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-11-24 12:08:37 -06:00