LLVM Clang 3.4 Compiler Optimization Levels

Benchmarking LLVM/Clang compiler optimization levels for a future article on phoronix.com.

HTML result view exported from: https://openbenchmarking.org/result/1307304-SO-CLANGLEVE44&sor&grt.

LLVM Clang 3.4 Compiler Optimization LevelsProcessorMotherboardChipsetMemoryDiskGraphicsAudioNetworkOSKernelDesktopDisplay ServerDisplay DriverOpenGLCompilerFile-SystemScreen Resolution-O0-O1-O2-Os-O3-OfastIntel Core i7 720Q @ 1.60GHz (8 Cores)LENOVO 4318CTOIntel Core DMI4096MB160GB INTEL SSDSA2M160NVIDIA Quadro FX 880M 1024MB (405/324MHz)Conexant CX20585Intel 82577LM Gigabit Connection + Intel Centrino Ultimate-N 6300Ubuntu 13.103.11.0-031100rc2-generic (x86_64)Xfce 4.10X Server 1.14.2nouveau 1.0.83.0 Mesa 9.1.4 Gallium 0.4Clang 3.4 (SVN 187338) + LLVM 3.4svnext41600x900OpenBenchmarking.orgCompiler Details- Optimized build; Built Jul 28 2013 (21:43:17); Default target: x86_64-unknown-linux-gnu; Host CPU: corei7 Processor Details- Scaling Governor: acpi-cpufreq ondemand

LLVM Clang 3.4 Compiler Optimization Levelsc-ray: Total Timeencode-flac: WAV To FLACgraphics-magick: Blurgraphics-magick: Sharpengraphics-magick: Resizinggraphics-magick: HWB Color Spacegraphics-magick: Local Adaptive Thresholdinghimeno: Poisson Pressure Solverencode-mp3: WAV To MP3n-queens: Elapsed Timescimark2: Fast Fourier Transformsmallpt: Global Illumination Renderer; 100 Sampleshmmer: Pfam Database Searchbuild-imagemagick: Time To Compilebuild-php: Time To Compile-O0-O1-O2-Os-O3-Ofast208.5344.12221024368127.9567.471083.88189.3077089.3323.1418.55100.1111.2653356681311105.3623.55386.21189.1041030.8957.3731.28103.779.0053366680321129.5622.72343.18189.7229227.3165.3035.51104.7211.1652366679301102.6823.04331.72190.1432028.6863.3333.4475.988.8653366680321055.0822.64345.38173.5729327.3365.8841.9793.638.8553366797311128.5022.00343.65188.0627527.1066.5542.15OpenBenchmarking.org

C-Ray

Total Time

OpenBenchmarking.orgSeconds, Fewer Is BetterC-Ray 1.1Total Time-O3-Ofast-O1-O2-Os-O050100150200250SE +/- 0.04, N = 3SE +/- 0.03, N = 3SE +/- 0.01, N = 3SE +/- 0.02, N = 3SE +/- 0.04, N = 3SE +/- 0.07, N = 375.9893.63100.11103.77104.72208.53-Ofast-O1-O2-Os-O01. (CC) gcc options: -lm -lpthread -O3 -march=native

FLAC Audio Encoding

WAV To FLAC

OpenBenchmarking.orgSeconds, Fewer Is BetterFLAC Audio Encoding 1.3.0WAV To FLAC-Ofast-O3-O2-Os-O1-O01020304050SE +/- 0.01, N = 5SE +/- 0.01, N = 5SE +/- 0.01, N = 5SE +/- 0.01, N = 5SE +/- 0.05, N = 5SE +/- 0.02, N = 58.858.869.0011.1611.2644.12-Ofast-O3-O2-Os-O1-O01. (CXX) g++ options: -march=native -fvisibility=hidden -logg -lm

GraphicsMagick

Operation: Blur

OpenBenchmarking.orgIterations Per Minute, More Is BetterGraphicsMagick 1.3.16Operation: Blur-Ofast-O3-O2-O1-Os-O01224364860SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.33, N = 3535353535222-Ofast-O3-O2-O1-Os-O01. (CC) gcc options: -march=native -pthread -lXext -lSM -lICE -lX11 -lxml2 -lz -lm -lpthread

GraphicsMagick

Operation: Sharpen

OpenBenchmarking.orgIterations Per Minute, More Is BetterGraphicsMagick 1.3.16Operation: Sharpen-Ofast-O3-Os-O2-O1-O0816243240SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3363636363510-Ofast-O3-Os-O2-O1-O01. (CC) gcc options: -march=native -pthread -lXext -lSM -lICE -lX11 -lxml2 -lz -lm -lpthread

GraphicsMagick

Operation: Resizing

OpenBenchmarking.orgIterations Per Minute, More Is BetterGraphicsMagick 1.3.16Operation: Resizing-Ofast-O3-Os-O2-O1-O01530456075SE +/- 0.33, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3676666666624-Ofast-O3-Os-O2-O1-O01. (CC) gcc options: -march=native -pthread -lXext -lSM -lICE -lX11 -lxml2 -lz -lm -lpthread

GraphicsMagick

Operation: HWB Color Space

OpenBenchmarking.orgIterations Per Minute, More Is BetterGraphicsMagick 1.3.16Operation: HWB Color Space-Ofast-O1-O3-O2-Os-O020406080100SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.33, N = 3978180807936-Ofast-O1-O3-O2-Os-O01. (CC) gcc options: -march=native -pthread -lXext -lSM -lICE -lX11 -lxml2 -lz -lm -lpthread

GraphicsMagick

Operation: Local Adaptive Thresholding

OpenBenchmarking.orgIterations Per Minute, More Is BetterGraphicsMagick 1.3.16Operation: Local Adaptive Thresholding-O3-O2-Ofast-O1-Os-O0714212835SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 3SE +/- 0.00, N = 332323131308-O3-O2-Ofast-O1-Os-O01. (CC) gcc options: -march=native -pthread -lXext -lSM -lICE -lX11 -lxml2 -lz -lm -lpthread

Himeno Benchmark

Poisson Pressure Solver

OpenBenchmarking.orgMFLOPS, More Is BetterHimeno Benchmark 3.0Poisson Pressure Solver-O2-Ofast-O1-Os-O3-O02004006008001000SE +/- 0.39, N = 3SE +/- 0.36, N = 3SE +/- 0.14, N = 3SE +/- 0.03, N = 3SE +/- 5.78, N = 3SE +/- 0.03, N = 31129.561128.501105.361102.681055.08127.95-O2-Ofast-O1-Os-O01. (CC) gcc options: -O3 -march=native

LAME MP3 Encoding

WAV To MP3

OpenBenchmarking.orgSeconds, Fewer Is BetterLAME MP3 Encoding 3.99.3WAV To MP3-Ofast-O3-O2-Os-O1-O01530456075SE +/- 0.01, N = 5SE +/- 0.02, N = 5SE +/- 0.01, N = 5SE +/- 0.01, N = 5SE +/- 0.01, N = 5SE +/- 0.02, N = 522.0022.6422.7223.0423.5567.47-Ofast-O3-O2-Os-O1-O01. (CC) gcc options: -pipe -march=native -lm

N-Queens

Elapsed Time

OpenBenchmarking.orgSeconds, Fewer Is BetterN-Queens 1.0Elapsed Time-Os-O2-Ofast-O3-O1-O02004006008001000SE +/- 0.13, N = 3SE +/- 0.03, N = 3SE +/- 0.04, N = 3SE +/- 0.89, N = 3SE +/- 0.00, N = 3SE +/- 0.13, N = 3331.72343.18343.65345.38386.211083.88-Os-O2-Ofast-O1-O01. (CC) gcc options: -static -fopenmp -O3 -march=native

SciMark

Computational Test: Fast Fourier Transform

OpenBenchmarking.orgMflops, More Is BetterSciMark 2.0Computational Test: Fast Fourier Transform-Os-O2-O0-O1-Ofast-O34080120160200SE +/- 0.00, N = 4SE +/- 0.24, N = 4SE +/- 0.00, N = 4SE +/- 0.52, N = 4SE +/- 0.41, N = 4SE +/- 0.61, N = 4190.14189.72189.30189.10188.06173.57-Os-O2-O0-O1-Ofast-O31. (CXX) g++ options: -march=native

Smallpt

Global Illumination Renderer; 100 Samples

OpenBenchmarking.orgSeconds, Fewer Is BetterSmallpt 1.0Global Illumination Renderer; 100 Samples-Ofast-O2-O3-Os-O1-O0170340510680850SE +/- 0.33, N = 3SE +/- 0.88, N = 3SE +/- 0.58, N = 3SE +/- 1.67, N = 3SE +/- 0.33, N = 3SE +/- 0.58, N = 3275292293320410770-Ofast-O2-O3-Os-O1-O01. (CXX) g++ options: -fopenmp -march=native

Timed HMMer Search

Pfam Database Search

OpenBenchmarking.orgSeconds, Fewer Is BetterTimed HMMer Search 2.3.2Pfam Database Search-Ofast-O2-O3-Os-O1-O020406080100SE +/- 0.04, N = 3SE +/- 0.05, N = 3SE +/- 0.02, N = 3SE +/- 0.06, N = 3SE +/- 0.03, N = 3SE +/- 0.46, N = 327.1027.3127.3328.6830.8989.33-Ofast-O2-O3-Os-O1-O01. (CC) gcc options: -march=native -pthread -lhmmer -lsquid -lm

Timed ImageMagick Compilation

Time To Compile

OpenBenchmarking.orgSeconds, Fewer Is BetterTimed ImageMagick Compilation 6.8.1-10Time To Compile-O0-O1-Os-O2-O3-Ofast1530456075SE +/- 0.03, N = 3SE +/- 0.11, N = 3SE +/- 0.14, N = 3SE +/- 0.22, N = 3SE +/- 0.18, N = 3SE +/- 0.12, N = 323.1457.3763.3365.3065.8866.55

Timed PHP Compilation

Time To Compile

OpenBenchmarking.orgSeconds, Fewer Is BetterTimed PHP Compilation 5.2.9Time To Compile-O0-O1-Os-O2-O3-Ofast1020304050SE +/- 0.01, N = 3SE +/- 0.02, N = 3SE +/- 0.01, N = 3SE +/- 0.07, N = 3SE +/- 0.10, N = 3SE +/- 0.03, N = 318.5531.2833.4435.5141.9742.15-O0-O1-Os-O2-O3-Ofast1. (CC) gcc options: -march=native -pedantic -ldl -lz -lm

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