Refer to the given 3-address code sequence from line 1001 to 1017. This code sequence is split into

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Question

Refer to the given 3-address code sequence from line 1001 to 1017. This code sequence is split into basic blocks. The number of basic blocks is ______.

Accepted Answer

Answer: 6Concept — Basic Blocks in Compiler Design: A basic block is a maximal sequence of consecutive instructions such that:Control flows into the block only at the first instruction (single entry point).Control flows out only at the last instruction (single exit point — no branches except at the end).Identifying Leaders: The first instruction of each basic block is called a leader. An instruction is a leader if:It is the first instruction of the program.It is the target of a branch instruction (conditional or unconditional).It immediately follows a branch instruction.Code analysis (instructions 1001–1017):   InstructionReason for being a Leader     1001: i=1First instruction of the program  1002: j=1Target of branch at 1011 (goto 1002)  1003: t1=10*iTarget of branch at 1009 (goto 1003)  1010: i=i+1Follows conditional branch at 1009  1012: i=1Follows conditional branch at 1011  1013: t5=i-1Target of branch at 1017 (goto 1013)   Basic Blocks:Block 1: Instructions 1001 (just i=1, since 1002 is a leader)Block 2: Instruction 1002 (just j=1, since 1003 is a leader)Block 3: Instructions 1003–1009 (ends at conditional branch)Block 4: Instructions 1010–1011 (ends at conditional branch)Block 5: Instruction 1012 (just i=1, since 1013 is a leader)Block 6: Instructions 1013–1017 (ends at conditional branch)Total = 6 basic blocks.

Refer to the given 3-address code sequence from line 1001 to 1017. This code sequence is split into basic blocks. The number of basic blocks is ______.

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Refer to the given 3-address code sequence from line 1001 to 1017. This code sequence is split into basic blocks. The number of basic blocks is ______.

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