[handshake] Fix sign-extension in ArithBound#822
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Prior to this PR, the pass performed extension of the result of a bounded `cond_br` based on the extension used for the operand. This is incorrect since they have no correlation in the algorithm's logic: The extension that should be used depends on the bound of the data operand, not the data operand itself. More specifically, since the optimization currently only implements unsigned comparisons, the result should then only ever be zero-extended. The only except is for `eq` and `ne` where the result should equal the extend of the constant. Fixes #817 Unblocks #816
Jiahui17
reviewed
Mar 29, 2026
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In addressing your comments I also found out that the logic is simply broken when the upper-bound is sign-extended. PTAL |
Jiahui17
approved these changes
Mar 30, 2026
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Prior to this PR, the pass performed extension of the result of a bounded
cond_brbased on the extension used for the operand. This is incorrect since they have no correlation in the algorithm's logic: The extension that should be used depends on the bound of the data operand, not the data operand itself.More specifically, since the optimization currently only implements unsigned comparisons, the result should then only ever be zero-extended. The only except is for
eqandnewhere the result should equal the extend of the constant.Fixes #817
Unblocks #816