Baum, Boyett, & Garrison Comparing Intel C++ and Microsoft Visual C++ Compilers Michael Baum David Boyett Holly Garrison

Baum, Boyett, & Garrison Agenda Problem Statement System Environment Programs Used for Comparison Matrix Processing Programs Results and Analysis SPEC Benchmark Results and Analysis Conclusion

Baum, Boyett, & Garrison Problem Statement The general purpose of our project is to verify Intel’s claim that their compiler is 10% better then the Microsoft Visual compiler. Data will be gathered using Intel VTune tool from both SPEC CPU 2000 benchmarks and from simple matrix processing programs.

Baum, Boyett, & Garrison System Environment Programs were run on a single processor system with Intel P4 2.4GHz processor and 512 MB RAM. – Windows 2000 operating system Microsoft Visual.NET compiler Intel C++ Compiler 7.1 for Windows Intel VTune Performance Analyzer 7.0

Baum, Boyett, & Garrison Programs Used for Comparison SPEC CPU 2000 Benchmark –164.gzip –300.twolf Simple Matrix Processing Programs –Array Summation of elements –Matrix Multiplication of 250x250 matrices

Baum, Boyett, & Garrison VTune Setup Using Intel’s VTune application the following events were measured: –Instruction Count –Clockticks and Clockticks per Instruction –Loads & Stores –Level 1 cache misses –Mispredicted Calls and Branches

Baum, Boyett, & Garrison Matrix Processing Programs Results Executable (*.exe) Mispredict ed Calls Mispredict ed Branches 1st Level Cache Misses LoadsStoresClockticks Instruction Count Clockticks per Instruction Array Sum (Intel)1,51822,28549,8901,268,145844,96218,995,295981, Array Sum (VC++)4,53639,123186,760863,7721,162,23913,069,2421,462, Matrix Mult 250 (Intel)2205, ,3249,502,5321,979, Matrix Mult 250 (VC++)28968,35418,640,24931,728,270657,32888,513,59454,242,

Baum, Boyett, & Garrison Matrix Processing Programs Results (cont.)

Baum, Boyett, & Garrison Matrix Processing Programs Results (cont.)

Baum, Boyett, & Garrison Matrix Processing Analysis For Simple Matrix and Array Processing the Intel compiler verified it’s claim of a 10% better compiler –With the exception of the number of Stores executed, the Intel compiler showed approximately a 50% savings in the measured operations. The Matrix Multiplication program showed one noteworthy result: the Intel compiler had zero events for both 1 st Level Cache Misses and for Loads. –Verified by multiple builds and runs

Baum, Boyett, & Garrison SPEC Benchmark Results Executable (*.exe) Mispredicte d Calls Mispredicte d Branches 1st Level Cache Misses LoadsStoresClockticks Instruction Count Clockticks per Instruction 164.gzip (Intel)11,725871,754,1722,267,577,93622,054,374,34211,101,416,840106,412,563,51576,670,596, gzip (VC++)7,695869,317,0152,273,066,85222,074,844,24811,108,909,049107,286,054,47076,671,138, twolf (Intel)3464,874,9827,639,21177,060,02532,577,657484,933,215210,922, twolf (VC++)5374,797,5527,526,58876,831,63833,214,416473,946,742211,425,

Baum, Boyett, & Garrison SPEC Benchmark Results

Baum, Boyett, & Garrison SPEC Benchmark Results

Baum, Boyett, & Garrison SPEC CPU 2000 Analysis SPEC CPU 2000 Benchmarks did not show any significant difference between the two compilers. SPEC Benchmarks were re-compiled and data sets were collected multiple times to verify the validity of the original data.

Baum, Boyett, & Garrison Conclusions Even though our group saw significant improvements in performance for our small test programs, these same gains could not be duplicated for the Benchmark applications. These variations might be the result of differences in program complexity.

Baum, Boyett, & Garrison Conclusions (cont.) The Intel C++ Compiler showed results that were equal to or in some cases better than those of Microsoft Visual C++. While Intel’s claim of 10% better results may not be true in all cases it is still a superior compiler.