Add a new API validate() to RRGraphBuilder

[m-hariszafar]

Description
This PR focuses on updating routing resource graph builder functions, where we use the refactored data structure RRGraphBuilder to shadow the discrete data structure rr_graph_storage.
This PR aims to fully refactored/deprecate the direct use of the legacy API validate() from the rr_node data structure.

After this PR, the validate() from the refactored data structure RRGraphBuilder is the only way to use it.

Checklist:

• Removed the legacy API validate() from rr_node.cpp and rr_node.h (if present)
• Added new API validate() to data structures RRGraphBuilder, whose comments are Doxygen compatible
• Replaced all the use of validate() in respective functions (if needed)

Related Issue
This pull request is a follow-up PR on the routing resource graph refactoring effort #1805, #1868

Motivation and Context
This PR is a continuation of the refactoring effort with a focus on shadowing the rr_graph_storage APIs in the RRGraphBuilder data structure.
This PR refactored the validate() API among the other APIs in #1847, #1868

How Has This Been Tested?

• All vtr basic and strong tests are passing.

Types of changes

• Bug fix (change which fixes an issue)
• New feature (change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed

[m-hariszafar]

QoR tests are completed and a quick summary is given below. QoR comparison files are also attached.

titan_quick_qor test:
flow run time -3.21% on average.
critical path delays 0% on average.
Peak memory usage -0.17% on average

vtr_reg_qor_chain_depop test:
Flow run time 6.41% on average.
critical path delays 0% on average.
Peak memory usage is -17.4% on average.

Here are the attached files
vtr_chain_depop.xlsx
titan_quick_qor.xlsx

[tangxifan]

@hariszafar-lm I cannot find validate() used by any client functions. Can you double check?

[m-hariszafar]

@hariszafar-lm I cannot find validate() used by any client functions. Can you double check?

Well, this function is only calling in rr_graph_storage.cpp where it defines. That's why I didn't change them.
And there is no other client function that is calling validate() through some hierarchy.

vtr-verilog-to-routing/vpr/src/route/rr_graph_storage.cpp

Line 514 in 5bd4549

VTR_ASSERT_SAFE(validate());

vtr-verilog-to-routing/vpr/src/route/rr_graph_storage.cpp

Line 763 in 5bd4549

VTR_ASSERT_SAFE(validate());

vtr-verilog-to-routing/vpr/src/route/rr_graph_storage.cpp

Line 809 in 5bd4549

VTR_ASSERT_SAFE(validate());

Let me know if something needs to change.

[tangxifan]

@hariszafar-lm I see. It means that the validate() is currently used as an internal method in the rr_graph_storage class. But I think it is needed to be a method in the public method of rr_graph_builder. We need the validator() to be called by the end of rr_graph building function.

Can you add the following comments to this API:

@note This function is used to validate the correctness of the routing resource graph in terms of graph attributes. Strongly recommend to call it when you finish the building a routing resource graph. If you need more advanced checks, which are related to architecture features, you should consider to use the check_rr_graph() function or build your own check_rr_graph() function.

@vaughnbetz Let me know if the comments make sense. Feel free to suggest.

[vaughnbetz]

Yes, those comments make sense to me.