Mohamed. M. Saad

 Java Virtual Machine Prototype based on Jikes RVM  Targets  Code profiling/visualization using execution flow  Utilize large number of cores through possible parallel portions of code

 Adaptive Online System  Compiler  Baseline Complier  JIT Compiler

Insert TM_start & TM_end at every independent possible path Lazy commit (write-buffer) Contention Resolution based on Program Order Execution Frequency

 Modifying the Baseline Compiler  TemplateCompilerFramework class ▪ Converting Java Bytecode into Machine language (Assembly) genCode(){ ….. switch(opcode){ case : emmit_ : } ▪ Plugin some code to profile block start event  Profiling execution using GraphViz script

int counter = 0; for(int i=0; i 0.3) counter++; else counter--; 0: iconst_0 1: istore_1 2: iconst_0 3: istore_2 4: goto 29 7: invokestatic #13; 10: ldc2_w #19; 13: dcmpl 14: ifle 23 17: iinc 1, 1 20: goto 26 23: iinc 1, -1 26: iinc 2, 1 29: iload_2 30: bipush 12 32: if_icmplt 7 35: return 0: iconst_0 1: istore_1 2: iconst_0 3: istore_2 4: goto 29 7: invokestatic #13; 10: ldc2_w #19; 13: dcmpl 14: ifle 23 17: iinc 1, 1 20: goto 26 23: iinc 1, -1 26: iinc 2, 1 29: iload_2 30: bipush 12 32: if_icmplt 7 35: return

public class Test{ public static void foo(){ int counter = 0; for(int i=0; i 0.3) counter++; else counter--; } public static void zoo(){ System.out.println("hi"); } public static void main(String[] args){ int i=6; if(i<10) foo(); else zoo(); } }

 Building execution flow tracking system  Split the code to basic blocks  Collect execution patterns  Visualizing execution  Parallelizing the execution of the code using different threads  Dependency analysis  Branch prediction  Packaging & grouping blocks (superblock)  Preserving program order and data consistency using STM  Checkpointing  Closed nesting in loop parallelization