Fedora 21 GCC Compiler Optimizations
Compiler optimization benchmarks by Michael Larabel for a future article on Phoronix.com.


-O0: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080

-O2: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080

-O3: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080

-O3 -march=native: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080

-O3 -march=native -flto: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080

-Ofast -march=native: 

	Processor: Intel Xeon E5-1680 v3 @ 3.80GHz (16 Cores), Motherboard: MSI X99S SLI PLUS (MS-7885) v1.0, Chipset: Intel Xeon E5 v3/Core, Memory: 16384MB, Disk: 80GB INTEL SSDSCKGW08, Graphics: eVGA NVIDIA GeForce GT 740 1024MB, Audio: Intel C610/X99, Monitor: VE228, Network: Intel Connection

	OS: Fedora 21, Kernel: 3.18.0-0.rc3.git2.2.fc22.1.x86_64 (x86_64), Desktop: GNOME Shell 3.14.1.5, Display Server: X Server 1.16.1, Display Driver: nouveau 1.0.10, OpenGL: 3.3 Mesa 10.3.2 Gallium 0.4, Compiler: GCC 4.9.2 20141101 + LLVM 3.4.2, File-System: ext4, Screen Resolution: 1920x1080


SciMark 2.0
Computational Test: Monte Carlo
Mflops > Higher Is Better
-O0 ..................... 599.65 |========================================
-O2 ..................... 600.06 |========================================
-O3 ..................... 591.22 |========================================
-O3 -march=native ....... 589.31 |=======================================
-O3 -march=native -flto . 673.31 |=============================================
-Ofast -march=native .... 602.01 |========================================


SciMark 2.0
Computational Test: Fast Fourier Transform
Mflops > Higher Is Better
-O0 ..................... 443.48 |==========================================
-O2 ..................... 472.28 |=============================================
-O3 ..................... 444.88 |==========================================
-O3 -march=native ....... 472.98 |=============================================
-O3 -march=native -flto . 467.81 |=============================================
-Ofast -march=native .... 458.28 |============================================


Gcrypt Library 1.4.4
CAMELLIA256-ECB Cipher
Microseconds < Lower Is Better
-O0 ..................... 7317 |===============================================
-O2 ..................... 1897 |============
-O3 ..................... 1972 |=============
-O3 -march=native ....... 1792 |============
-O3 -march=native -flto . 1997 |=============


GraphicsMagick 1.3.19
Operation: Blur
Iterations Per Minute > Higher Is Better
-O0 .................. 66  |========================
-O2 .................. 100 |=====================================
-O3 .................. 104 |======================================
-O3 -march=native .... 138 |===================================================
-Ofast -march=native . 137 |===================================================


GraphicsMagick 1.3.19
Operation: Sharpen
Iterations Per Minute > Higher Is Better
-O0 .................. 60  |======================
-O2 .................. 130 |===============================================
-O3 .................. 128 |==============================================
-O3 -march=native .... 141 |===================================================
-Ofast -march=native . 141 |===================================================


GraphicsMagick 1.3.19
Operation: Resizing
Iterations Per Minute > Higher Is Better
-O0 .................. 98  |===========================
-O2 .................. 177 |==================================================
-O3 .................. 172 |================================================
-O3 -march=native .... 182 |===================================================
-Ofast -march=native . 182 |===================================================


GraphicsMagick 1.3.19
Operation: HWB Color Space
Iterations Per Minute > Higher Is Better
-O0 .................. 98  |=========================
-O2 .................. 144 |=====================================
-O3 .................. 141 |=====================================
-O3 -march=native .... 168 |===========================================
-Ofast -march=native . 197 |===================================================


GraphicsMagick 1.3.19
Operation: Local Adaptive Thresholding
Iterations Per Minute > Higher Is Better
-O0 .................. 19 |===========
-O2 .................. 92 |====================================================
-O3 .................. 92 |====================================================
-O3 -march=native .... 92 |====================================================
-Ofast -march=native . 92 |====================================================


Himeno Benchmark 3.0
Poisson Pressure Solver
MFLOPS > Higher Is Better
-O0 ..................... 461.42  |=========
-O2 ..................... 1996.72 |========================================
-O3 ..................... 1997.60 |========================================
-O3 -march=native ....... 1909.10 |======================================
-O3 -march=native -flto . 2222.87 |============================================
-Ofast -march=native .... 2119.06 |==========================================


Timed Apache Compilation 2.4.7
Time To Compile
Seconds < Lower Is Better
-O0 .................. 17.63 |==========================
-O2 .................. 30.34 |=============================================
-O3 .................. 32.72 |=================================================
-O3 -march=native .... 26.82 |========================================
-Ofast -march=native . 26.39 |========================================


C-Ray 1.1
Total Time
Seconds < Lower Is Better
-O0 ..................... 36.27 |==============================================
-O2 ..................... 23.78 |==============================
-O3 ..................... 13.69 |=================
-O3 -march=native ....... 9.33  |============
-O3 -march=native -flto . 9.32  |============
-Ofast -march=native .... 8.46  |===========


Primesieve 5.4
1e12 Prime Number Generation
Seconds < Lower Is Better
-O0 ..................... 214.14 |=============================================
-O2 ..................... 45.86  |==========
-O3 ..................... 45.90  |==========
-O3 -march=native ....... 43.20  |=========
-O3 -march=native -flto . 43.16  |=========
-Ofast -march=native .... 43.19  |=========


FLAC Audio Encoding 1.3.0
WAV To FLAC
Seconds < Lower Is Better
-O0 .................. 20.89 |=================================================
-O2 .................. 5.58  |=============
-O3 .................. 4.77  |===========
-O3 -march=native .... 3.93  |=========
-Ofast -march=native . 3.89  |=========


LAME MP3 Encoding 3.99.3
WAV To MP3
Seconds < Lower Is Better
-O0 .................. 34.07 |=================================================
-O2 .................. 12.91 |===================
-O3 .................. 12.32 |==================
-O3 -march=native .... 11.38 |================
-Ofast -march=native . 10.44 |===============