Commit Graph

24 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
Anand Krishnamoorthi f50a9744ff feat(azure-policy): implement condition, expression, field, and template dispatch compilation (#686)
Fill in the compiler stubs for the evaluation layer.

Condition and wildcard compilation:
- Compile allOf/anyOf/not constraints, operator conditions with
  value-condition guards, and implicit allOf for unbound [*] fields
  via recursive Every loops.
- Defensively lowercase prefix/suffix path segments in wildcard
  handling for consistency with the collect path.

Expression and field compilation:
- Parse ARM template expressions and dispatch calls to parameters,
  field, current, resourceGroup, subscription, and others.
- Compile all FieldKind variants (type, id, name, location, tags,
  aliases, dynamic if/concat), resolve resource paths, and collect
  wildcard values via ForEach loops.

Template function dispatch:
- Wire up 50+ ARM template functions covering string, numeric,
  encoding, collection, date/time, logical, and comparison categories.

Compiler infrastructure (core.rs):
- Add emit helpers: load_literal, emit_builtin_call,
  emit_chained_index_literal_path, load_input, load_context,
  emit_coalesce_undefined_to_null, add_literal_u16, and
  get_or_add_builtin_index.
- Add alias resolution via resolve_alias_path and strip_fq_prefix.

Misc cleanup:
- Handle ARM template `[[` escape sequences in json_value_to_runtime
  and add a test for it.
- Tighten module visibility (pub -> pub(crate)/pub(super)) where
  appropriate.
- Add span context to bail errors in stubs so diagnostics carry
  source locations.
- Take CountBinding by reference in compile_from_binding.
- Suppress clippy warnings on the no-op memory_check stub.
2026-04-21 16:51:08 -05:00
Anand Krishnamoorthi 4d35744c4f feat(rvm): implement Azure Policy condition evaluation (#661)
Add VM support for Azure Policy's condition operators and allOf/anyOf
short-circuit logic, gated behind cfg(feature = "azure_policy").

Policy conditions (equals, contains, like, match, exists, and their
negations — 21 total) are encoded as a single PolicyCondition
instruction with a PolicyOp sub-opcode rather than bloating the
Instruction enum with 21 variants. The dispatch handles Azure Policy's
quirky comparison semantics: case-insensitive string comparison,
string↔number coercion, null vs undefined distinction, and element-wise
collection membership.

allOf/anyOf blocks use four instructions — LogicalBlockStart,
AllOfNext/AnyOfNext, and LogicalBlockEnd — that wire up a result
register and short-circuit on the first failing (allOf) or passing
(anyOf) child.

Helper functions for case-folded comparison, wildcard/glob matching, and
type coercion live in builtins::azure_policy::helpers.

Two YAML test suites (~2200 lines) exercise the full operator matrix and
the allOf/anyOf control flow.
2026-04-07 19:04:24 -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 e5ac9a2734 feat(rvm): new instructions and loop semantics for Azure Policy support (#659)
The Rego VM was designed around Rego's semantics, but Azure Policy needs
a few things Rego doesn't: host-supplied context alongside input/data,
undefined-to-null coercion for missing fields, skip-undefined collection
behavior for wildcard aliases, and non-vacuous iteration over non-array
values.

This commit adds five new instructions to bridge those gaps:

  LoadContext / LoadMetadata — give programs access to host-supplied
  evaluation context and cached program metadata at runtime.

  ArrayPushDefined — like ArrayPush but silently drops undefined values,
  so wildcard alias collection (field[*].property) excludes absent
  nested properties instead of leaking undefined entries into the array.

  ReturnUndefinedIfNotTrue — early return with Undefined when a guard
  condition isn't satisfied, without tripping a VM assertion failure.
  This models "condition doesn't match" cleanly.

  CoalesceUndefinedToNull — turns Undefined into Null in-place so that
  downstream builtins see null rather than short-circuiting on undefined.

The loop engine also gains an Azure Policy mode: when the source language
is "azure_policy", an Every loop over a non-array value (scalars, null,
objects) iterates once over a virtual Null element instead of being
vacuously true.  This matches how field[*] behaves on non-array fields
in Azure Policy — the condition body runs once against Null, which
typically evaluates to false.

On the plumbing side: the VM gets a context field with set_context(),
metadata is cached as a Value on program load, and map_limit_error is
inlined into memory_check since it had only one call site.

Four new YAML test suites (~880 lines) cover the new instructions and
context/metadata loading, along with instruction parser, display, and
assembly listing support for everything added here.
2026-04-06 15:40:41 -05:00
Anand Krishnamoorthi 95bffcb5f9 feat(rvm): extend program metadata and bump serialization to v6 (#654)
Add typed metadata support to RVM programs so that language frontends
can store language identity and arbitrary annotations alongside the
compiled bytecode.

Program metadata:
- Add `language` field to identify the source language (e.g. "rego",
  "azure_policy") so the VM can adjust semantics at runtime
- Add `annotations` map (BTreeMap<String, MetadataValue>) for
  frontend-specific key-value metadata
- Add MetadataValue enum with String, Bool, Integer, Float, Array,
  and Object variants, plus full serde support
- Add to_value() conversion for runtime access from VM instructions
- Add has_host_await flag with recompute_host_await_presence()

Serialization:
- Bump binary format version from 5 to 6
- Add JSON serialization for the new metadata fields

Assembly listing:
- Display language and annotations in the program header

Compiler:
- Track has_host_await during Rego compilation
2026-04-03 12:53:42 -05:00
Anand Krishnamoorthi 126cc12eb5 refactor: consolidate RVM instruction variants and clean up VM internals (#651)
Merge the three separate Assert* instructions (AssertNot, AssertCondition,
AssertNotUndefined) into a single `Guard { register, mode }` instruction
with a GuardMode enum. This cuts duplicated match arms across display,
listing, parser, dispatch, and all compiler emit sites.

Drop the unnecessary `#[repr(C)]` from the Instruction enum. It was never
exposed across FFI, so the C-compatible 4-byte discriminant was pure waste.
Without it Rust picks a 1-byte discriminant, shrinking every instruction
from 8 bytes to 6. A new `instruction_size` unit test locks this at 6.

While touching these files, also clean up several long-standing issues:

- Deduplicate the iteration-state setup in loops.rs by extracting a shared
  resolve_iteration_state() helper -- the stack-based and stackless paths
  had near-identical 40-line blocks.
- Collapse the ExitWithSuccess / ExitWithFailure match arms into one.
- In rules.rs, stop cloning Arc<Program> just to borrow a RuleInfo -- clone
  the small RuleInfo struct directly and extract a get_rule_info() helper.
- Move the memory check into dispatch (runs per instruction) and remove the
  now-dead enforce_memory_check() entry-point calls.
- Apply map_or_else style throughout listing.rs for consistency.
2026-04-01 05:34:33 -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 50c0215fdb Rvm optimizations (#620)
* perf(rvm): fix O(n²) comprehension yield by mutating in-place

Instead of cloning the entire accumulator collection on every yield
iteration, use take_register + Rc::make_mut to get exclusive ownership
and mutate in-place. This reduces comprehension yield from O(n²) to O(n)
for both run-to-completion and suspendable execution modes.

- Add RegoVM::take_register() helper that swaps register with Undefined
- Comprehension yield now takes the accumulator, mutates via Rc::make_mut,
  and writes back — avoiding deep clones when refcount == 1

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

* perf(rvm): use take_register for ObjectSet, ArrayPush, SetAdd

These instructions were cloning the container register (bumping Rc to 2),
then calling as_object_mut/as_array_mut/as_set_mut which invokes
Rc::make_mut — deep-cloning the entire collection since refcount > 1.

Use take_register instead so the Rc refcount stays at 1, making
Rc::make_mut a no-op and allowing in-place mutation.

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

* perf(rvm): remove unnecessary clones in rule caching

- execute_call_rule_common: move final_value into cache instead of
  cloning, since it is not used afterwards
- finalize_rule_frame_data: add comment clarifying the clone is needed
  because the value is both cached and returned
- Remove unnecessary .clone() on result_from_rule when setting register

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

* rvm: avoid RuleInfo clone per rule call

Replace RuleInfo.clone() (which heap-allocates name, destructuring_blocks, and
potentially function_info) with a cheap Arc<Program> clone (atomic refcount
bump) followed by borrowing &RuleInfo from the local Arc. This eliminates
per-rule-call heap allocations.

Sites changed:
- execute_call_rule_common: Arc clone + borrow
- execute_call_rule_suspendable: Arc clone + borrow
- finalize_rule_frame_data: Arc clone + borrow
- handle_rule_break_event: inline Arc clone + borrow (was get_rule_info)
- handle_rule_error_event: inline Arc clone + borrow (was get_rule_info)
- Removed now-unused get_rule_info method

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

* rvm: replace bincode with postcard for serialization

Remove unlinked bincode dependency. Use postcard (already a dep for rvm feature)
for all binary serialization/deserialization in program serialization and tests.

Also adds rvm_benchmark benchmark.

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

* perf(rvm): cache dummy Span/Expr for builtin calls

Every builtin call was allocating a Source (via from_contents), a Span, and
N Ref<Expr> wrappers just to satisfy the builtin function signature. These
dummy values are only used for error reporting context.

Cache the dummy Span and Vec<Ref<Expr>> on the RegoVM struct. The Source and
Span are created once on first builtin call; dummy Expr entries grow as
needed and are reused across calls via mem::take/put-back pattern.

This eliminates per-builtin-call heap allocations for Source (Rc + String +
Vec<lines>), Span clones, and Rc<Expr> wrappers.

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

* perf(rvm): round 2 allocation reduction in builtins, entry points, virtual data

- Cache builtin args Vec on RegoVM (mem::take/clear/put-back pattern)
- Restructure builtins_cache as two-level map for clone-free lookup
- Use IndexMap::get_index() in execute_entry_point_by_index
- Use mutable Vec path stack in traverse_rule_tree_subobject (push/pop)
- Walk data tree and rule-result paths by reference, clone only leaf
- Use mem::replace in resume() instead of cloning ExecutionState

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

* fix(rvm): address PR review feedback

- Restore cached_builtin_args on all error/early-return paths in
  execute_builtin_call to preserve allocation reuse
- Use 1-based line/col and \"<builtin>\" filename in dummy span for
  clearer diagnostics
- Restore result register before returning errors in comprehension
  mode-mismatch branches (both run-to-completion and suspendable)
- Avoid clone in resume() invalid-state error path by formatting
  debug string before moving state back

---------

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-03-11 21:39:58 -05:00
Anand Krishnamoorthi ee3dff9a3d fix(ci): skip mimalloc FFI and disable isolation for Miri (#621)
- Add cfg(not(miri)) guards to mimalloc module, global allocator, and
  allocator-memory-limits code paths so Miri falls back to the default
  system allocator instead of calling unsupported FFI functions.
- Set MIRIFLAGS="-Zmiri-disable-isolation" in the workflow so tests
  that perform file I/O can run under Miri.
- Skip units/parse tests under Miri due to Float-vs-BigInt Number
  representation mismatch with Miri's soft-float emulation.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-03-11 15:13:51 -05:00
Anand Krishnamoorthi 006e819d52 rvm: switch binary serialization to postcard (#582)
Move RVM binary encoding from bincode to postcard and bump the format version. Update test helpers, docs, changelog, and refresh lockfiles after the swap.

Closes #575

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-03-03 15:09:45 -06:00
Anand Krishnamoorthi 10eebfe54c test(rvm): Move vm execution limit tests to a separate test to avoid flakiness (#558)
Having a separate integration test allows the execution tests to freely
change the global fallback limits without affecting other tests.

also ask release-plz to ignore xtask package

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-29 04:15:33 +05:30
Anand Krishnamoorthi 394625d4bc feat!: add cooperative execution-time limits across engine, VM, and binding (#539)
- Introduce ExecutionTimer/ExecutionTimerConfig to allow limiting evaluating time.
- To amortize time checking costs, checking interval can be configured via the notion of work units
- A global fallback time limit can be set to universally limit all evaluation in addition to engine level limit setting.
- Implement limnits in interpreter and RVM. In RVM, also handle suspend/resume so that time during pause is not counted.
- Add engine-level APIs to set/clear per-engine timer configuration and apply global fallback defaults.
- Surface execution-time limits through FFI and C# bindings
- Add C# tests and example usage to validate engine overrides, global fallback behavior, and compiled policy enforcement.
- Expand docs for execution-time limit
- Add interpreter YAML cases and VM unit tests for time-limit behavior and deterministic time sources.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-28 05:58:03 +05:30
Anand Krishnamoorthi fd59bb5a91 feat(memory): Allocator-backed global memory limits (#544)
Policy evaluation at scale needs to be able to set memory limits
so that a bad policy does not hog memory or to ensure that
policy evaluation itself does not use too much memory which could
cause other components to suffer.

This PR introduces capability to set and enforce global memory limits.
It also lays the groundwork for enabling per evaluation limits in future.

Once a global memory limit is set, Regorus maintains per thread counters
to track memory activity (allocation, deallocation) of a thread.
These counters are periodically flushed to global memory counters.
Per thread counters avoid the contention that updating global counters
on each alloc/free would cause.

Policy evaluation periodically checks these counters and raises errors
if allocated memory has exceeded the configured limit.

Currently memory limit capability is exposed only to FFI and C#.

Also update mimalloc to v2.2.6

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-24 07:08:54 +05:30
Anand Krishnamoorthi 740db8a0f5 chore: Harden RVM implementation (#537)
Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2026-01-14 06:07:31 +05:30
Anand Krishnamoorthi 28891ef883 chore: Harden instructions and program (#535)
Also enforce sane limits in program

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-30 18:20:07 -06:00
Anand Krishnamoorthi 249dcd0b43 chore: Add clippy lints (#529)
Lints are added (deny) at crate level.

In each offending file, the failing lints are explicitly allowed.
Each file will be fixed in subsequent PRs.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-23 15:59:34 -06:00
Anand Krishnamoorthi a232b13e50 feat: Else blocks in definitions
- ensure both run-to-completion and suspendable rule execution stop evaluating
  bodies once one succeeds so later else branches are skipped
- test cases

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 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 12c083e29e test: Add RVM compiler testing to ACI tests (#509)
code fixes:
  - compiler: add `is_var_bound_in_current_scope` and use it in destructuring so
    only the innermost scope blocks rebinding while still catching duplicates
    within that block.
  - rvm: treat `not` over undefined operands as a successful negation to match
    interpreter semantics.

tests/aci:
   migrate YAML cases to `data.policy.rule` queries with `{x: …}`
  bindings, expand the harness to run interpreter plus RVM (with optional
  skipping), align results to the binding format, add readable timing output,
  and support a `--filter` flag for targeting cases.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-12-01 16:58:44 -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
Anand Krishnamoorthi 49bd3c22f3 feat!: add Rego Virtual Machine (RVM) implementation (#495)
* feat!: add Rego Virtual Machine (RVM) implementation

This commit introduces a register-based virtual machine for executing Rego
policies with bytecode-style instructions. Unlike the existing tree-walking
interpreter, the RVM compiles policies into instruction sequences that operate
on virtual registers, offering better performance and optimization potential.

Core Components:

Instruction Set Architecture:
- Define instruction types for data operations, control flow, and builtins
- Implement instruction parameter encoding and display formatting
- Add instruction parser with comprehensive test coverage

Virtual Machine Engine:
- Register-based execution model with program counter management
- Loop execution supporting iterators, comprehensions, and quantifiers
- Function call handling with argument evaluation and context management
- Rule evaluation with default value resolution and virtual data support
- Arithmetic and comparison operation implementations

Program Representation:
- Program listing builder with instruction sequencing
- Rule tree construction for organizing policy rules
- Binary and JSON serialization for compiled programs
- Recompilation support for program modification

Testing Infrastructure:
- Extensive YAML test suites covering all VM features
- Rust unit tests for VM execution and instruction parsing
- Test suites for loops, comprehensions, builtins, and control flow

BREAKING CHANGE: Introduces new VM execution path alongside interpreter

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

* docs: add detailed RVM architecture references

Introduce architecture.md explaining program artifacts, serialization, and runtime subsystems.
Document the full opcode catalog in instruction-set.md, including operands, parameter tables, and outcomes.
Walk through execution flow, stacks, and operational guidance in vm-runtime.md, tying the runtime to the new architecture docs.

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

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Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>
2025-11-14 11:43:19 -06:00