Apr 9, 2026 · Accepted

Experiment 036: Compiler Hints (Dart + C)

Date: 2026-04-09

Status: Accepted

Changes

Dart:

• @pragma('vm:prefer-inline') on _fastDecodeText (hot text decode path)

C:

• __attribute__((hot)) on 6 hot functions: buf_write, buf_ensure,

json_write_string, write_json_to_buf, resqlite_step_row, fast_i64_to_str

• __restrict on buf_write and json_write_string parameters
• __builtin_expect on buf_ensure capacity check (likely) and

resqlite_step_row exit check (unlikely)

Results

No isolated signal — these are compiler optimization hints that affect code

generation quality. The Dart pragma primarily helps AOT (Flutter release builds)

rather than JIT benchmarks.

Decision

Accepted — zero-risk annotations. No behavioral changes. The __restrict

qualifier helps the C compiler eliminate redundant loads in the JSON buffer

write path. The __builtin_expect hints align branch prediction with the

actual hot path (buffer has capacity, step returns SQLITE_ROW).