Add brief fast generator description.
@@ -259,7 +259,8 @@ ex100: func v, 0
* **Assign**: priority-based assigning hard regs and stack slots to registers
* **Rewrite**: transform MIR according to the assign using reserved hard regs
* **Combine** (code selection): merging data-depended insns into one
- * **Dead Code Elimination**: removing insns with unused outputs.
+ * **Dead Code Elimination**: removing insns with unused outputs
+ * **Fast Generator**: 4-5 times faster generation of code whose performance is on par with `-O0` of GCC/Clang
* **Generate Machine Insns**: run machine-dependent code creating machine insns
## C to MIR translation
