Bug 197792 - [B3::ReduceStrength] specializeSelect should update m_root and clear the m_valueForConstant cache
Summary: [B3::ReduceStrength] specializeSelect should update m_root and clear the m_va...
Status: RESOLVED DUPLICATE of bug 197756
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Robin Morisset
URL:
Keywords:
Depends on: 197265
Blocks:
  Show dependency tree / graph
 
Reported: 2019-05-10 12:59 PDT by Robin Morisset
Modified: 2019-05-10 13:00 PDT (History)
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Description Robin Morisset 2019-05-10 12:59:25 PDT 
When I added https://bugs.webkit.org/show_bug.cgi?id=197265 I assumed that which block is the root does not change in the middle of strength reduction.
But specializeSelect can use splitForward, which for some odd reason uses a new block for the first half of the given block (instead of using a new block for the second half, as I expected).
So if the block being split is the root block I must update m_root and erase the m_valueInConstant cache.
Erasing the cache cannot cause wrong results: at most it can make us miss some optimization opportunities in this iteration of the fixpoint.
Comment 1 Robin Morisset 2019-05-10 12:59:39 PDT 
rdar://problem/50641659
Comment 2 Robin Morisset 2019-05-10 13:00:45 PDT 

*** This bug has been marked as a duplicate of bug 197756 ***