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Double Pumping in HLS

BigHandsomeBee
249 Views

I'm learning how to optimize C++ code for efficient high-level synthesis.

I'm looking at the memory banking code provided in Quartus Prime Pro hls/examples/tutorials folder.

One piece of code is shown like below:

BigHandsomeBee_0-1621484987049.png

According to what I understand, this should generate single memory bank with two store ports and two load ports. However, when opening the synthesis report, memory view shows as below:

BigHandsomeBee_1-1621485134625.png

First I can understand the initialization store can reuse the same store ports with the other two stores.

What I don't understand is why the other two stores share the same store port.

And when I click the share symbol, it says at the bottom, accesses are mutually exclusive, no arbitration? How can the two stores be mutually exclusive?

BigHandsomeBee_2-1621485275350.png

 

 

0 Kudos
2 Replies
BoonBengT_Intel
Moderator
211 Views

Hi @BigHandsomeBee,

 

Thank you for posting in Intel community forum and hope this message find you well.
The behavior you are noticing should be part of the HLS merging memories trying to reduce area required.
Please do refer to the following details explanation here and hope it helps you to understand better.

 

Best Wishes
BB

BoonBengT_Intel
Moderator
164 Views

Hi @BigHandsomeBee,

 

Greetings, unfortunately as we do not receive any further clarification on what is provided. Hence thread will now be transitioned to community support. If you have new queries, please feel free to open a new thread and we will be right with you. Otherwise, the community users will further help you with doubts in this thread. Pleasure having you here.

 

Best Wishes
BB

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