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3989236154
On 32-bit platforms (ESP32 Xtensa), 64-bit shifts in varint parsing compile to __ashldi3 library calls. Since the vast majority of protobuf varint fields (message types, sizes, enum values, sensor readings) fit in 4 bytes, the 64-bit arithmetic is unnecessary overhead on the common path. Split parse() into two phases: - Bytes 0-3: uint32_t loop with native 32-bit shifts (0, 7, 14, 21) - Bytes 4-9: noinline parse_wide_() with uint64_t, only for BLE addresses and other 64-bit fields The code generator auto-detects which proto messages use int64/uint64/ sint64 fields and emits USE_API_VARINT64 conditionally. On non-BLE configs, parse_wide_() and the 64-bit accessors (as_uint64, as_int64, as_sint64) are compiled out entirely. Saves ~40 bytes flash on non-BLE configs. Benchmark shows 25-50% faster parsing for 1-4 byte varints (the common case).
