code-review-asm-xtensa

Perform comprehensive manual review of Xtensa assembly code in FastLED ESP32 platforms for correctness, ABI compliance, safety, and performance. ## What Gets Checked ### Critical Errors (Must Fix) - **E001**: Invalid `movi` for 32-bit addresses - **E002**: Wrong return instruction in interrupts - **E003**: Missing `memw` memory barriers for MMIO writes - **E004**: Windowed ABI used in interrupt handlers - **E005**: Unaligned memory access - **E006**: Missing `IRAM_ATTR` on interrupt handlers - **E007**: Mixed ABI usage in same function ### Performance Warnings - **W001-W005**: Load-use hazards, loop overhead, nesting depth, register pressure, dependency chains ### Optimization Opportunities - **O001-O004**: Array indexing, conditional moves, loop unrolling, code density Search for Xtensa assembly code in git changes (inline asm and .S files) and perform deep analysis.