Simplify HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop #3013
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Get rid of three divisions. The original expression was:
opmin := min((oend0 - op0) / 10, (oend1 - op1) / 10, (oend2 - op2) / 10, (oend3 - op3) / 10)
r15 := min(r15, opmin)
The division by 10 can be moved outside the `min`:
opmin := min(oend0 - op0, oend1 - op1, oend2 - op2, oend3 - op3)
r15 := min(r15, opmin/10)
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When reading the asm code (great job, by the way!), I noticed that it's possible to remove three divisions by 10. The original expression was:
The division by 10 can be moved outside
min:make testpassed. I check on an Ice Lake machine that there's no performance regression.zstd -i5 -b1 1MBfileshowed 1194 MB/s for the currentdev, with this change 1201 MB/s.