舍 Basic Block Defn Basic Block:A consecutive sequence of instructions/ code such that control is“straight'" (no jump targets except at the beginning, no jumps except at the end) 1.x=y+Z 2.z=t+I 3.jmp 3 4.x=y+Z 3 basic blocks 5.z=t+i 6.jmp 1 7.jmp 4 6Defn Basic Block: A consecutive sequence of instructions / code such that • the instruction in each position always executes before (dominates) all those in later positions, and • no outside instruction can execute between two instructions in the sequence control is “straight” (no jump targets except at the beginning, no jumps except at the end) Basic Block 6 1. x = y + z 2. z = t + I 3. jmp 3 4. x = y + z 5. z = t + i 6. jmp 1 7. jmp 4 3 basic blocks