Promote 16-bit allocated counts to unsigned before absl::bit_width in CentralFreeList. - #722
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Promote 16-bit allocated counts to unsigned before absl::bit_width in CentralFreeList.#722copybara-service[bot] wants to merge 1 commit into
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… CentralFreeList. Calling absl::bit_width on uint16_t dispatches to CountLeadingZeroes16, which executes extra shifts and masking compared to native 32-bit lzcnt/clz instructions. Promoting prev_allocated and cur_allocated to unsigned in ReleaseToSpans and RemoveRange elides this 16-bit bit-manipulation overhead under the CentralFreeList spinlock. PiperOrigin-RevId: 979995927
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Promote 16-bit allocated counts to unsigned before absl::bit_width in CentralFreeList.
Calling absl::bit_width on uint16_t dispatches to CountLeadingZeroes16, which executes extra shifts and masking compared to native 32-bit lzcnt/clz instructions. Promoting prev_allocated and cur_allocated to unsigned in ReleaseToSpans and RemoveRange elides this 16-bit bit-manipulation overhead under the CentralFreeList spinlock.