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SSA-CFG: Fix detection of equivalent instructions in Outliner#16768

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ssa-cfg-fix-outliner
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SSA-CFG: Fix detection of equivalent instructions in Outliner#16768
blishko wants to merge 1 commit into
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ssa-cfg-fix-outliner

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@blishko blishko commented May 22, 2026

In the helper we use to check if arguments of two instructions are equivalent, we would say that two instructions are equivalent if they have the same index.
This is, however, not correct, as the two instructions can come from two different CFGs. Thus, same indices does not mean they refer to the same instruction.

We fixed the check instead to

  • Check if we have proven equivalence before; or
  • The two instructions refer to the same literal

In the helper we use to check if arguments of two instructions are
equivalent, we would say that two instructions are equivalent if they
have the same index.
This is, however, not correct, as the two instructions can come from two
different CFGs. Thus, same indices does not mean they refer to the same
instruction.

We fixed the check instead to
- Check if we have proven equivalence before; or
- The two instructions refer to the same literal
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github-actions Bot commented Jun 6, 2026

This pull request is stale because it has been open for 14 days with no activity.
It will be closed in 7 days unless the stale label is removed.

@github-actions github-actions Bot added the stale The issue/PR was marked as stale because it has been open for too long. label Jun 6, 2026
@blishko blishko added experimental and removed stale The issue/PR was marked as stale because it has been open for too long. labels Jun 6, 2026
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