Compile Options - 2023.2 English

The syn.compile commands specify the default behavior for compilation of the HLS component.

syn.compile.design_size_max_warning

Specifies the design size that triggers a warning related to slow compilation or poor QoR.

syn.compile.design_size_maximum_warning=300000

syn.compile.enable_auto_rewind

When true enables an alternative HLS implementation for pipelined loops which uses automatic loop rewind as described in the Rewinding Pipelined Loops for Performance section of the Vitis HLS User Guide (UG1399) for additional information.

syn.compile.enable_auto_rewind=1

syn.compile.ignore_long_run_time

Disable long run time warning.

syn.compile.ignore_long_run_time=1

syn.compile.name_max_length <arg>

The name_max_length option will specify the maximum length of function names. If the length is over the threshold, the last part of the name will be truncated.

syn.compile.name_max_length=13

syn.compile.no_signed_zeros

The no_signed_zeros option will ignore the signedness of floating point zero so that compiler can do aggressive optimizations on floating point operations.

syn.compile.no_signed_zeros=1

syn.compile.pipeline_flush_in_task arg

Specifies that pipelines in hls::tasks will be flushing (flp) by default to reduce the probability of deadlocks in C/RTL Co-simulation. This option applies to pipelines that achieve an II=1 with the default option of ii1. However, you can also specify it as applying always to enable flushing pipelines in either hls::tasks or dataflow, or can be completely disabled using never. Refer to Flushing Pipelines and Pipeline Types in Vitis High-Level Synthesis User Guide (UG1399) for more information.

Important: Flushing pipelines (flp) are compatible with the rewind option specified in the PIPELINE pragma or directive when the syn.compile.enable_auto_rewind option is also specified.

always

Always make pipelines flushable in hls::tasks or dataflow regardless of II.

never

Never make pipeline flushable unless specifically overridden by other directives or pragmas.

ii1

Make pipelines that achieve II=1 flushable in hls::tasks. This is the default setting.

syn.compile.pipeline_flush_in_task=always

syn.compile.pipeline_loops arg

Loops with a tripcount equal to or greater than the specified value will be pipelined automatically.

syn.compile.pipeline_loops=20

syn.compile.pipeline_style arg

Set default pipeline style, this is a preference not a hard constraint. Refer to Flushing Pipelines and Pipeline Types in Vitis High-Level Synthesis User Guide (UG1399) for more information. The three styles are: stallable (stp), flushable (flp), and free-running (frp). The default is free-running.

syn.compile.pipeline_style=flp

syn.compile.pragma_strict_mode

Enable errors instead of warnings for unrecognized and improper pragma syntax.

syn.compile.pragma_strict_mode=1

syn.compile.unsafe_math_optimizations

The unsafe_math_optimizations option will ignore the signedness of floating point zero and enable associative floating point operations so that compiler can do aggressive optimizations on floating point operations.

syn.compile.unsafe_math_optimizations=1

Important: Using this option might change the result of any floating point calculations and result in a mismatch in C/RTL co-simulation. Ensure your test bench is tolerant of differences and checks for a margin of difference, not exact values.