Revert "Cranelift: Reassociate long and narrow chains of operations into shallow and wide trees (#7466)"#12116
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…nto shallow and wide trees (bytecodealliance#7466)" This reverts commit 72534b0. This mid-end rule was shown to be the root cause of a codegen regression in bytecodealliance#12106 and we didn't have any real examples that would improve from this rule, just a theoretical idea of its benefit. Better to do actual instruction scheduling while lowering and/or during regalloc than to do hack-y instruction scheduling in the mid-end (where we have no idea how many registers are available, for example).
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LGTM, thanks!
(Looks like some disas tests will need re-blessing as well to pass CI.)
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…nto shallow and wide trees (bytecodealliance#7466)" (bytecodealliance#12116) * Revert "Cranelift: Reassociate long and narrow chains of operations into shallow and wide trees (bytecodealliance#7466)" This reverts commit 72534b0. This mid-end rule was shown to be the root cause of a codegen regression in bytecodealliance#12106 and we didn't have any real examples that would improve from this rule, just a theoretical idea of its benefit. Better to do actual instruction scheduling while lowering and/or during regalloc than to do hack-y instruction scheduling in the mid-end (where we have no idea how many registers are available, for example). * update disas tests
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This reverts commit 72534b0.
This mid-end rule was shown to be the root cause of a codegen regression in #12106 and we didn't have any real examples that would improve from this rule, just a theoretical idea of its benefit. Better to do actual instruction scheduling while lowering and/or during regalloc than to do hack-y instruction scheduling in the mid-end (where we have no idea how many registers are available, for example).