Visible to Intel only — GUID: bzs1565998705944
Ixiasoft
Visible to Intel only — GUID: bzs1565998705944
Ixiasoft
1.12.6.1. Enabling or Disabling Fractal Synthesis
For Stratix® 10 and Agilex™ family devices, fractal synthesis optimization runs automatically for small multipliers (any A*B statement in Verilog HDL or VHDL where bit-width of the operands is 7 or less). You can also disable automatic fractal synthesis for small multipliers for these devices using either of the following methods:
- In RTL, set the DSP multstyle, as "Multstyle Verilog HDL Synthesis Attribute" describes. For example:
(* multstyle = "dsp" *) module foo(...); module foo(..) /* synthesis multstyle = "dsp" */;
- In the .qsf file, add as an assignment as follows:
set_instance_assignment -name DSP_BLOCK_BALANCING_IMPLEMENTATION \ DSP_BLOCKS -to r
In addition, for Stratix® 10, Arria® 10, Cyclone® 10 GX, and Agilex™ family devices, you can enable fractal synthesis globally or for specific multipliers with the Fractal Synthesis GUI option or the corresponding FRACTAL_SYNTHESIS .qsf assignment:
- In RTL, use altera_attribute as follows:
(* altera_attribute = "-name FRACTAL_SYNTHESIS ON" *)
- In the .qsf file, add as an assignment as follows:
set_global_assignment -name FRACTAL_SYNTHESIS ON -entity <module name>
In the user interface, follow these steps:
- Click Assignments > Assignment Editor.
- Select Fractal Synthesis for Assignment Name, On for the Value, the arithmetic-intensive entity name for Entity, and an instance name in the To column. You can enter a wildcard (*) for To to assign all instances of the entity.
Figure 111. Fractal Synthesis Assignment in Assignment Editor