prometeu-runtime/docs/specs/pbs/files/PRs para Junie.md

PR-21 — Distinguish peek, borrow, and mutate in Core IR

Goal

Restore the semantic distinction mandated by PBS.

Required Semantics

Operation	Effect
peek	Copy storage → stack value
borrow	Temporary read-only view
mutate	Temporary mutable view + commit

Required Changes

• Lower PBS peek → BeginPeek / EndPeek
• Lower PBS borrow → BeginBorrow / EndBorrow
• Lower PBS mutate → BeginMutate / EndMutate

These must not share the same lowering path.

Tests

• PBS snippet with all three operations
• Assert distinct Core IR instruction sequences

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PR-22 — Make Allocation Shape Explicit in Core IR

Goal

Stop implicit / guessed heap layouts.

Required Changes

• Replace any shape-less Alloc with:

Alloc { ty: TypeId, slots: u32 }

Rules:

• TypeId comes from frontend type checking
• slots is derived deterministically (struct fields / array size)

Tests

• Allocating storage struct emits correct slots
• Allocating array emits correct slots

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PR-23 — Eliminate Invalid Call Fallbacks

Goal

Prevent invalid bytecode generation.

Required Changes

• Remove all fallbacks to FunctionId(0) or equivalent

• On unresolved symbols during lowering:

  • Emit canonical diagnostic (E_RESOLVE_UNDEFINED or E_LOWER_UNSUPPORTED)
  • Abort lowering

Tests

• PBS program calling missing function → compile error
• No Core IR or VM IR emitted

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PR-24 — Validate Contract Calls in Frontend (Arity + Types)

Goal

Move contract validation to compile time.

Required Changes

• During PBS type checking:

  • Validate argument count against contract signature
  • Validate argument types

• Lower only validated calls to HostCall

Tests

• Wrong arity → E_TYPE_MISMATCH
• Correct call lowers to Core IR HostCall

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PR-25 — Core IR Invariants Test Suite

Goal

Lock in correct semantics before touching the VM.

Required Invariants

• Every Begin* has a matching End*
• Gate passed to Begin* is available at End*
• No storage writes without BeginMutate
• No silent fallbacks

Tests

• Property-style tests or golden IR assertions

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STOP POINT

After PR-25:

• Core IR correctly represents PBS HIP semantics
• Lowering is deterministic and safe
• VM is still unchanged

Only after this point may VM PRs begin.

Any VM work before this is a hard rejection.

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Instruction to Junie

If any rule in this document is unclear:

• Stop
• Add a failing test
• Document the ambiguity

Do not invent behavior.

This document is binding.