• Shenghou Ma's avatar
    runtime: inline several float64 routines to speed up complex128 division · 0157c72d
    Shenghou Ma authored
    Depends on CL 6197045.
    
    Result obtained on Core i7 620M, Darwin/amd64:
    benchmark                       old ns/op    new ns/op    delta
    BenchmarkComplex128DivNormal           57           28  -50.78%
    BenchmarkComplex128DivNisNaN           49           15  -68.90%
    BenchmarkComplex128DivDisNaN           49           15  -67.88%
    BenchmarkComplex128DivNisInf           40           12  -68.50%
    BenchmarkComplex128DivDisInf           33           13  -61.06%
    
    Result obtained on Core i7 620M, Darwin/386:
    benchmark                       old ns/op    new ns/op    delta
    BenchmarkComplex128DivNormal           89           50  -44.05%
    BenchmarkComplex128DivNisNaN          307          802  +161.24%
    BenchmarkComplex128DivDisNaN          309          788  +155.02%
    BenchmarkComplex128DivNisInf          278          237  -14.75%
    BenchmarkComplex128DivDisInf           46           22  -52.46%
    
    Result obtained on 700MHz OMAP4460, Linux/ARM:
    benchmark                       old ns/op    new ns/op    delta
    BenchmarkComplex128DivNormal         1557          465  -70.13%
    BenchmarkComplex128DivNisNaN         1443          220  -84.75%
    BenchmarkComplex128DivDisNaN         1481          218  -85.28%
    BenchmarkComplex128DivNisInf          952          216  -77.31%
    BenchmarkComplex128DivDisInf          861          231  -73.17%
    
    The 386 version has a performance regression, but as we have
    decided to use SSE2 instead of x87 FPU for 386 too (issue 3912),
    I won't address this issue.
    
    R=dsymonds, mchaten, iant, dave, mtj, rsc, r
    CC=golang-dev
    https://golang.org/cl/6024045
    0157c72d
print.c 5.69 KB