[NFC] Add tests for missing exact CFP optimizations #7890
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CFP takes advantage of exact type information, but it currently does so only for immutable fields. It is also unnecessarily conservative about how it propagates type information so that sets to a type inhibit optimizations of its sibling types, even though those sets cannot possibly affect the siblings. Add tests for these cases to demonstrate the benefit of follow-on PRs that will fix these issues.
kripken
reviewed
Sep 8, 2025
| (struct.get $A 0 | ||
| (local.get $A-exact) | ||
| ) | ||
| ) |
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To be sure I follow, we can (in principle) optimize $A because there is no inexact set of it anywhere?
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Right. The only value that has ever been written to an (exact $A) is the value it was allocated with.
kripken
approved these changes
Sep 8, 2025
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CFP takes advantage of exact type information, but it currently does so
only for immutable fields. It is also unnecessarily conservative about
how it propagates type information so that sets to a type inhibit
optimizations of its sibling types, even though those sets cannot
possibly affect the siblings.
Add tests for these cases to demonstrate the benefit of follow-on PRs
that will fix these issues.