GPU610/NullPointerException

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NullPointerException

Team Members

1. Philip A Aziz
2. Saad Mohammad
3. Natesh Mayuranathan

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Philip Aziz:

• Philip Aziz - Calculating Prime Numbers

Only the inner loop would be possible to Parellelize but would still require to validate 1 prime number at a time due to need to validate against previous prime numbers.

while (count < n){

               flag = 1;
               i = 1;
               checkKey = int((sqrt (prime))+1);
               //checks prime numbers for divisible values
               while(primes[i] < checkKey and flag){
                       if ((prime % primes[i])==0){
                               flag = 0;
                       }
                       i++;
               }
               if(flag){
                       primes[count] = prime;
                       count++;
               }
               prime +=2;
       }

Time by Level

n	Elapsed Time
10,000	0
100,000	1
1,000,000	8
10,000,000	220
100,000,000	6200

Saad Mohammad:

Project

Encrypts and decrypts images. Original project file can be found at: Image-Encrypt Github

Profiling Resource

Profiled the application using:

SYSTEM

Matrix

IMAGE

JPEG Format

324KB

1598 x 982

CUSTOM MAKEFILE

# Makefile for Assignment 1
# Saad Mohammad
#

GCC_VERSION = 4.7.1
PREFIX = /usr/local/gcc/${GCC_VERSION}/bin/
CC = ${PREFIX}gcc
CPP = ${PREFIX}g++

image_encrypt: main.o encryptjpeg.o accessjpeg.o aesencrypt.o
	$(CPP) -pg -ow1 main.o encryptjpeg.o accessjpeg.o aesencrypt.o -o image_encrypt
	rm *.o
	chmod +x+x+x image_encrypt

main.o: main.cpp
	$(CPP) -c -O2 -g -pg -std=c++0x main.cpp

encryptjpeg.o: encryptjpeg.cpp
	$(CPP) -c -O2 -g -pg -std=c++0x encryptjpeg.cpp

accessjpeg.o: accessjpeg.cpp
	$(CPP) -c -O2 -g -pg -std=c++0x accessjpeg.cpp

aesencrypt.o: aesencrypt.cpp
	$(CPP) -c -O2 -g -pg -std=c++0x aesencrypt.cpp

clean:
	rm -f image_encrypt *.o

Profiling Results

Encryption:

Each sample counts as 0.01 seconds.

 %   cumulative   self              self     total           
time   seconds   seconds    calls  us/call  us/call  name    
53.85      0.14     0.14  5979744     0.02     0.02  aesEncrypt::ffmul(unsigned char, unsigned char)
30.77      0.22     0.08   207630     0.39     0.39  aesEncrypt::subBytes(char*)
11.54      0.25     0.03   186867     0.16     0.91  aesEncrypt::mixColumns(char*)
 3.85      0.26     0.01    20763     0.48    12.52  aesEncrypt::encryptBlock(char*)
 0.00      0.26     0.00   207630     0.00     0.00  aesEncrypt::shiftRows(char*)
 0.00      0.26     0.00    20764     0.00     0.00  accessJpeg::hasMore()
 0.00      0.26     0.00    20763     0.00     0.00  accessJpeg::accessBlock()
 0.00      0.26     0.00       40     0.00     0.00  aesEncrypt::sboxify(unsigned char)
 0.00      0.26     0.00       10     0.00     0.00  aesEncrypt::roundify(unsigned char)
 0.00      0.26     0.00        1     0.00     0.00  _GLOBAL__sub_I__ZN10accessJpegC2Ev
 0.00      0.26     0.00        1     0.00     0.00  _GLOBAL__sub_I__ZN11encryptJpeg7processEc
 0.00      0.26     0.00        1     0.00     0.00  _GLOBAL__sub_I_main
 0.00      0.26     0.00        1     0.00     0.00  accessJpeg::readInFile(char*)
 0.00      0.26     0.00        1     0.00     0.00  accessJpeg::jumpToStart()
 0.00      0.26     0.00        1     0.00     0.00  accessJpeg::writeOutFile(char*)
 0.00      0.26     0.00        1     0.00     0.00  accessJpeg::~accessJpeg()
 0.00      0.26     0.00        1     0.00     0.00  aesEncrypt::setTextKey(std::string)
 0.00      0.26     0.00        1     0.00     0.00  aesEncrypt::expandKey()
 0.00      0.26     0.00        1     0.00     0.00  aesEncrypt::~aesEncrypt()

Decryption:

Each sample counts as 0.01 seconds.

 %   cumulative   self              self     total           
time   seconds   seconds    calls  us/call  us/call  name    
58.97      0.23     0.23 11959488     0.02     0.02  aesEncrypt::ffmul(unsigned char, unsigned char)
25.64      0.33     0.10   207630     0.48     0.48  aesEncrypt::invSubBytes(char*)
 7.69      0.36     0.03   186867     0.16     1.39  aesEncrypt::invMixColumns(char*)
 5.13      0.38     0.02    20763     0.96    18.78  aesEncrypt::decryptBlock(char*)
 2.56      0.39     0.01   207630     0.05     0.05  aesEncrypt::invShiftRows(char*)
 0.00      0.39     0.00    20764     0.00     0.00  accessJpeg::hasMore()
 0.00      0.39     0.00    20763     0.00     0.00  accessJpeg::accessBlock()
 0.00      0.39     0.00       40     0.00     0.00  aesEncrypt::sboxify(unsigned char)
 0.00      0.39     0.00       10     0.00     0.00  aesEncrypt::roundify(unsigned char)
 0.00      0.39     0.00        1     0.00     0.00  _GLOBAL__sub_I__ZN10accessJpegC2Ev
 0.00      0.39     0.00        1     0.00     0.00  _GLOBAL__sub_I__ZN11encryptJpeg7processEc
 0.00      0.39     0.00        1     0.00     0.00  _GLOBAL__sub_I_main
 0.00      0.39     0.00        1     0.00     0.00  accessJpeg::readInFile(char*)
 0.00      0.39     0.00        1     0.00     0.00  accessJpeg::jumpToStart()
 0.00      0.39     0.00        1     0.00     0.00  accessJpeg::writeOutFile(char*)
 0.00      0.39     0.00        1     0.00     0.00  accessJpeg::~accessJpeg()
 0.00      0.39     0.00        1     0.00     0.00  aesEncrypt::setTextKey(std::string)
 0.00      0.39     0.00        1     0.00     0.00  aesEncrypt::expandKey()
 0.00      0.39     0.00        1     0.00     0.00  aesEncrypt::~aesEncrypt()