improvement(semantic/cfg): rework error path.

[rzvxa]

This PR aims to provide a more accurate error/finalization flow, I've nuked the old error path approach and rewrote it with more versatility in mind.

We used to visit the finalizer block twice and create 2 sets of AstNodes/Basic Blocks for them, This was there to differentiate between the error path finalizer and success path one. There is no longer a need for having 2 separate sets of nodes to do this differentiation.

As for the error path now we have 2 kinds of them, Everything is attached to an error block - even if it is not in a try-catch statement - this results in a lot of extra edges to keep track of these "Implicit" error blocks but I believe in future it can help us to track cross block error paths, For example, we can dynamically attach and cache the implicit error block of a function to its call site error path (either implicit or explicit).

[graphite-app]

Your org has enabled the Graphite merge queue for merging into main

Add the label “merge” to the PR and Graphite will automatically add it to the merge queue when it’s ready to merge. Or use the label “hotfix” to add to the merge queue as a hot fix.

You must have a Graphite account and log in to Graphite in order to use the merge queue. Sign up using this link.

[rzvxa]

• feat(linter/eslint): add no_unreachable rule. #3238 : 2 dependent PRs (#3631 , #3650 )
• feat(semantic/cfg): propagate unreachable edges through subgraphs. #3648
• feat(semantic/cfg): add Condition instruction. #3567
• feat(semantic/cfg): add iteration instructions. #3566
• improvement(semantic/cfg): better control flow for switch statements. #3547
• improvement(semantic/cfg): rework error path. #3519 👈
• improvement(semantic/cfg): better throw control flow. #3473
• improvement(linter/react): use CFG for detecting cyclic subgraphs in rules-of-hooks. #3454
• improvement(semantic/cfg): better CFG API #3472
• improvement(semantic/cfg): better break and continue flow. #3462
• improvement(semantic/cfg): better control flow for ForStatements. #3453
• improvement(semantic/cfg): better control flow for DoWhileStatements. #3452
• improvement(semantic/cfg): better control flow for WhileStatements. #3451
• improvement(semantic/cfg): rework basic blocks. #3381
• fix(linter): memorize visited block id in neighbors_filtered_by_edge_weight #3407
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

Join @rzvxa and the rest of your teammates on Graphite

[codspeed-hq]

CodSpeed Performance Report

Merging #3519 will not alter performance

_{Comparing 06-03-improvement_semantic_cfg_rework_error_path (9b30971) with main (59666e0)}

Summary

✅ 22 untouched benchmarks

[rzvxa]

@Boshen This stack is ready for review.

There is one thing I want you to consider carefully and give feedback on it. I've added a lot of "Implicit" error edges, Basically every basic block has an error edge even when it's not in a try block, And every function (+Program) has a basic block to harness these errors similar to a catch block. It results in extra memory usage and doesn't have a real impact on our current workflow I've mostly added them for forward compatibility if we want to handle cross-module/cross-function error unwinding.

So regarding your concern around this subject (#3641) we may want to make these edges optional or remove them altogether until we find a real use case. I added them when I wasn't aware that memory usage is an issue in the semantics.

[graphite-app]

Merge activity

• Jun 13, 3:25 AM EDT: Boshen added this pull request to the Graphite merge queue.
• Jun 13, 3:44 AM EDT: Boshen merged this pull request with the Graphite merge queue.