prometeu-runtime/files/TODOs.md

PR-5.4 — Verifier Integration for Syscall Slot Rules

Briefing

The verifier must ensure that syscall calls respect argument and return slot counts before runtime.

Target

• Extend verifier to validate syscall usage.

Work items

• At syscall call sites:

  • Look up SyscallMeta.
  • Ensure enough argument slots are available.
  • Ensure stack shape after call matches ret_slots.

• Emit verifier errors for mismatches.

Acceptance checklist

• Verifier rejects incorrect syscall slot usage.
• Correct programs pass.
• Runtime traps are not required for verifier-detectable cases.
• cargo test passes.

Tests

• Add tests:

  • Too few args for syscall → verifier error.
  • Correct args/returns → passes.

Junie instructions

You MAY:

• Extend verifier with syscall checks.

You MUST NOT:

• Change runtime trap logic.
• Add new trap categories.

If unclear:

• Ask before enforcing slot rules.

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PR-5.5 — Remove Legacy Syscall Entry Paths

Briefing

Any old or experimental syscall entry paths must be removed so that the slot-based ABI is the only supported mechanism.

Target

• Ensure only the new unified syscall dispatch path exists.

Work items

• Search for legacy or alternate syscall invocation logic.
• Remove or refactor them to use the canonical dispatch.
• Update modules and exports accordingly.

Acceptance checklist

• Only one syscall dispatch path remains.
• No legacy syscall logic is present.
• cargo test passes.

Tests

• Existing tests only.

Junie instructions

You MAY:

• Remove legacy syscall code paths.
• Refactor callers to use the unified dispatch.

You MUST NOT:

• Introduce new syscall semantics.
• Keep compatibility shims.

If unclear:

• Ask before deleting anything that looks externally visible.

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PR-5.6 — Syscall Multi-Return Tests

Briefing

We must ensure multi-return syscalls behave correctly with the slot-based ABI.

Target

• Add deterministic tests covering multi-return behavior.

Work items

• Create or adapt at least one syscall with ret_slots > 1.

• Add tests:

  • Verify correct stack results after syscall.
  • Verify incorrect caller expectations fail verification.

Acceptance checklist

• Multi-return syscalls behave correctly.
• Verifier catches mismatches.
• cargo test passes.

Tests

• New multi-return syscall tests.

Junie instructions

You MAY:

• Add deterministic tests.
• Use existing syscalls or create a simple test-only syscall.

You MUST NOT:

• Modify syscall semantics to satisfy tests.
• Add nondeterministic behavior.

If unclear:

• Ask before introducing new test syscalls.