Intel® Quartus® Prime Standard Edition User Guide: Third-party Synthesis

ID 683796
Date 9/24/2018
Document Table of Contents Inferring Shift Registers

The Synplify software infers shift registers for sequential shift components so that they can be placed in dedicated memory blocks in supported device architectures using the ALTSHIFT_TAPS IP core.

If necessary, set the implementation style with the syn_srlstyle attribute. If you do not want the components automatically mapped to shift registers, set the value to registers. You can set the value globally, or on individual modules or registers.

For some designs, turning off shift register inference improves the design performance.