Files
regorus/tests/rvm/vm/suites/resource_limits.yaml
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>

---------

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

218 lines
6.7 KiB
YAML

# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.
# Resource Limits Test Suite
# Tests instruction count limits, recursion depth, and resource exhaustion scenarios
# Verifies VM handles resource constraints gracefully
cases:
- note: instruction_limit_in_simple_loop
description: Instruction limit exceeded in simple loop
example_rego: "some x in [1, 2, 3, 4, 5]; x > 0"
literals:
- 1
- 2
- 3
- 4
- 5
- 0
max_instructions: 10 # Limit low enough that execution exceeds it before completion
instruction_params:
loop_params:
- mode: "Any"
collection: 0
key_reg: 10
value_reg: 11
result_reg: 12
body_start: 13
loop_end: 17
instructions:
- "ArrayNew { dest: 0 }"
- "Load { dest: 1, literal_idx: 0 }"
- "ArrayPush { arr: 0, value: 1 }"
- "Load { dest: 2, literal_idx: 1 }"
- "ArrayPush { arr: 0, value: 2 }"
- "Load { dest: 3, literal_idx: 2 }"
- "ArrayPush { arr: 0, value: 3 }"
- "Load { dest: 4, literal_idx: 3 }"
- "ArrayPush { arr: 0, value: 4 }"
- "Load { dest: 5, literal_idx: 4 }"
- "ArrayPush { arr: 0, value: 5 }"
- "LoopStart { params_index: 0 }"
- "Load { dest: 13, literal_idx: 5 }"
- "Gt { dest: 14, left: 11, right: 13 }"
- "AssertCondition { condition: 14 }"
- "LoopNext { body_start: 13, loop_end: 17 }"
- "Return { value: 12 }"
want_error: "exceeded maximum instruction limit"
- note: instruction_limit_in_comprehension
description: Instruction limit exceeded during comprehension
example_rego: "[x | x := [1, 2, 3, 4, 5][_]]"
literals:
- 1
- 2
- 3
- 4
- 5
max_instructions: 25
instruction_params:
comprehension_begin_params:
- mode: "Array"
collection_reg: 0
result_reg: 0
key_reg: 10
value_reg: 11
body_start: 13
comprehension_end: 17
loop_params:
- mode: "ForEach"
collection: 6
key_reg: 10
value_reg: 11
result_reg: 12
body_start: 13
loop_end: 17
instructions:
- "ArrayNew { dest: 6 }"
- "Load { dest: 1, literal_idx: 0 }"
- "ArrayPush { arr: 6, value: 1 }"
- "Load { dest: 2, literal_idx: 1 }"
- "ArrayPush { arr: 6, value: 2 }"
- "Load { dest: 3, literal_idx: 2 }"
- "ArrayPush { arr: 6, value: 3 }"
- "Load { dest: 4, literal_idx: 3 }"
- "ArrayPush { arr: 6, value: 4 }"
- "Load { dest: 5, literal_idx: 4 }"
- "ArrayPush { arr: 6, value: 5 }"
- "ComprehensionBegin { params_index: 0 }"
- "LoopStart { params_index: 0 }"
- "ComprehensionYield { value_reg: 11 }"
- "LoopNext { body_start: 13, loop_end: 17 }"
- "ComprehensionEnd"
- "Return { value: 0 }"
want_error: "exceeded maximum instruction limit"
- note: instruction_limit_in_nested_loops
description: Instruction limit exceeded in nested loops
example_rego: "some x in [1, 2]; some y in [3, 4]; x + y > 0"
literals:
- 1
- 2
- 3
- 4
- 0
max_instructions: 30
instruction_params:
loop_params:
- mode: "Any"
collection: 0
key_reg: 10
value_reg: 11
result_reg: 12
body_start: 5
loop_end: 18
- mode: "Any"
collection: 2
key_reg: 20
value_reg: 21
result_reg: 22
body_start: 8
loop_end: 16
instructions:
- "ArrayNew { dest: 0 }"
- "Load { dest: 1, literal_idx: 0 }"
- "ArrayPush { arr: 0, value: 1 }"
- "Load { dest: 3, literal_idx: 1 }"
- "ArrayPush { arr: 0, value: 3 }"
- "LoopStart { params_index: 0 }"
- "ArrayNew { dest: 2 }"
- "Load { dest: 4, literal_idx: 2 }"
- "ArrayPush { arr: 2, value: 4 }"
- "Load { dest: 5, literal_idx: 3 }"
- "ArrayPush { arr: 2, value: 5 }"
- "LoopStart { params_index: 1 }"
- "Add { dest: 30, left: 11, right: 21 }"
- "Load { dest: 31, literal_idx: 4 }"
- "Gt { dest: 32, left: 30, right: 31 }"
- "AssertCondition { condition: 32 }"
- "LoopNext { body_start: 8, loop_end: 16 }"
- "AssertCondition { condition: 22 }"
- "LoopNext { body_start: 5, loop_end: 18 }"
- "Return { value: 12 }"
want_error: "exceeded maximum instruction limit"
- note: large_literal_table_access
description: Access literal near u16 bounds (valid case)
literals:
- 42
instructions:
- "Load { dest: 0, literal_idx: 0 }"
- "Return { value: 0 }"
want_result: 42
- note: literal_index_out_of_bounds
description: Literal index beyond table bounds should error
literals:
- 42
instructions:
- "Load { dest: 0, literal_idx: 999 }"
- "Return { value: 0 }"
want_error: "Literal index 999 out of bounds"
- note: instruction_limit_with_early_return
description: Instruction limit allows early successful completion
example_rego: "some x in [1, 2]; x == 1"
literals:
- 1
- 2
max_instructions: 200 # Allow enough headroom for both execution modes
instruction_params:
loop_params:
- mode: "Any"
collection: 0
key_reg: 10
value_reg: 11
result_reg: 12
body_start: 6
loop_end: 9
instructions:
- "ArrayNew { dest: 0 }"
- "Load { dest: 1, literal_idx: 0 }"
- "ArrayPush { arr: 0, value: 1 }"
- "Load { dest: 2, literal_idx: 1 }"
- "ArrayPush { arr: 0, value: 2 }"
- "LoopStart { params_index: 0 }"
- "Load { dest: 13, literal_idx: 0 }"
- "Eq { dest: 14, left: 11, right: 13 }"
- "AssertCondition { condition: 14 }"
- "LoopNext { body_start: 6, loop_end: 9 }"
- "Return { value: 12 }"
want_result: true
- note: many_registers_usage
description: Test using high register numbers near upper bound without error
example_rego: "Store values in registers near VM upper bound"
literals:
- 1
- 2
- 3
instructions:
- "Load { dest: 0, literal_idx: 0 }"
- "Load { dest: 25, literal_idx: 1 }"
- "Load { dest: 49, literal_idx: 2 }"
- "Add { dest: 30, left: 0, right: 25 }"
- "Add { dest: 48, left: 30, right: 49 }"
- "Return { value: 48 }"
want_result: 6
- note: zero_instruction_limit
description: Zero instruction limit should error immediately
literals:
- 42
max_instructions: 0
instructions:
- "Load { dest: 0, literal_idx: 0 }"
- "Return { value: 0 }"
want_error: "exceeded maximum instruction limit"