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Add "slti" instruction support #4

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21a10c7
Add "slti" instruction support
vftable Aug 21, 2025
f474fd0
Update README.md
vftable Aug 21, 2025
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2 changes: 1 addition & 1 deletion README.md
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Expand Up @@ -26,7 +26,7 @@ You may think that the emulator is unreasonably slow, but if you take a look at
## Technical details

CPU emulates:
* All RV32I instructions except for "slti"
* All RV32I instructions
* All RV32M instructions except for "mulhsu"
* All RV32A instructions except for xor, max, min
* All Zicsr instructions
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13 changes: 13 additions & 0 deletions cpu/instruction_executer.py
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Expand Up @@ -148,6 +148,19 @@ def execute_instruction(instruction, registers, CSR_registers, trap_and_interrup
logger.register_executed_instruction(f"slli x{destination_reg}, x{source_reg}, {immediate_val} (Shift Left Logical - Immediate)")
pass

# --- instruction "SLTI" ---
elif instruction_subtype == 2:

if (source_reg_value & ((1 << 32) - 1)) - ((source_reg_value & (1 << (32 - 1))) << 1) < immediate_val:
result = 1
else:
result = 0

registers.x[destination_reg] = result

logger.register_executed_instruction(f"slti x{destination_reg}, x{source_reg}, {immediate_val} (Set Less Than - Immediate)")
pass

# --- instruction "SLTIU" ---
elif instruction_subtype == 3:

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