Tool Instruction Counter: Wrong total number of instructions and Wrong SSLI instruction type

[neittien0110]

Description

1. The total number of instructions is always 1 more than the actual instructions.
2. The type of SLLI is R-type, but it should be I-type.
   

Probability

• Always

Environment
Using tools Instruction Counter, version 1.0 (Felipe Lessa) on RARS version 1.6

[neittien0110]

Wrong SSLI instruction type

• Source code: https://github.com/TheThirdOne/rars/blob/master/src/rars/riscv/instructions/SLLI.java
• Extracted Code:

    public SLLI() {
      super("slli t1,t2,10", "Shift left logical : Set t1 to result of shifting t2 left by number of bits specified by immediate",
              BasicInstructionFormat.R_FORMAT, "0000000 ttttt sssss 001 fffff 0010011",false);
      }

• Detail: SLLI should be I_FORMAT.
• Propose: replace BasicInstructionFormat.R_FORMAT by BasicInstructionFormat.I_FORMAT

Wrong total number of instructions

• Source file of the tool: InstructionCounter.java
• Extracted Code to classify Instruction Type

protected void processRISCVUpdate(Observable resource, AccessNotice notice) {
        //...............................................................
        lastAddress = a;
        counter++;
        try {
            ProgramStatement stmt = Memory.getInstance().getStatement(a);
            
            // If the program is finished, getStatement() will return null,
            // a null statement will cause the simulator to stall.
            if(stmt != null) {
	            BasicInstruction instr = (BasicInstruction) stmt.getInstruction();
	            BasicInstructionFormat format = instr.getInstructionFormat();
	            if (format == BasicInstructionFormat.R_FORMAT)
	                counterR++;
        //...............................................................

• Detail: **counter++; ** is always executed before checking stmt !=null
• Propose: move instruction counter++; to be inside the block if(stmt != null) { }

[neittien0110]

just propose, not fix