🤖 AI text below 🤖
Problem Statement
OpenQASM import currently marks every custom gate that requires structured control flow as non-unitary. This includes gates with statically bounded for loops whose bodies contain only unitary operations. Callers of such gates also remain non-unitary, which prevents later unitary-only handling even when the source gate is safe.
This follows up on the final review of #2338.
Proposed Solution
Add conservative unitary recognition for structured custom-gate bodies. Support at least statically bounded for loops whose bodies contain only unitary operations or calls to unitary gates. Propagate the result through callers.
Leave functions unmarked when they contain non-unitary operations, recursion, unresolved calls, or unsupported control flow. Add import and round-trip tests for accepted loops and rejected non-unitary bodies.
🤖 AI text below 🤖
Problem Statement
OpenQASM import currently marks every custom gate that requires structured control flow as non-unitary. This includes gates with statically bounded
forloops whose bodies contain only unitary operations. Callers of such gates also remain non-unitary, which prevents later unitary-only handling even when the source gate is safe.This follows up on the final review of #2338.
Proposed Solution
Add conservative unitary recognition for structured custom-gate bodies. Support at least statically bounded
forloops whose bodies contain only unitary operations or calls to unitary gates. Propagate the result through callers.Leave functions unmarked when they contain non-unitary operations, recursion, unresolved calls, or unsupported control flow. Add import and round-trip tests for accepted loops and rejected non-unitary bodies.