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A comment on Apple CPU tricks: memory reordering, JavaScript support, ref counting.

Re:Apple CPU tricks: memory reordering, JavaScript support, ... by danvk on Friday November 27, 2020 @07:53PM (#25234083)
Can someone say more about the JavaScript optimization?
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Re:Apple CPU tricks: memory reordering, JavaScript support, ... by tjalfi on Friday November 27, 2020 @08:45PM (#25234385)
They might be referring to the ARM FJCVTZS instruction[0].

It speeds up converting JavaScript doubles to 32-bit integers.

[1] is the Webkit commit that added support for FJCVTZS, it was between a 0.5 to 2% speedup - that's a big win for a mature optimizer.

[0] https://stackoverflow.com/a/50966903/

[1] https://bugs.webkit.org/show_bug.cgi?id=184023#c24

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Re:Apple CPU tricks: memory reordering, JavaScript support, ... by annilt on Friday November 27, 2020 @08:53PM (#25234429)
In addition to FJCVTZS instruction, they added more floating point execution units and registers. Also did lower latency of pipelined fp instructions
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