Merge pull request #2819 from o1-labs/o1vm/riscv32im/test-decoding-add

o1vm/riscv32im: test decoding add

o1vm/src/interpreters/riscv32im/tests.rs

@@ -1,13 +1,68 @@
+use super::{registers::Registers, witness::Env, INSTRUCTION_SET_SIZE, PAGE_SIZE, SCRATCH_SIZE};
 use crate::interpreters::riscv32im::{
     constraints,
     interpreter::{
-        IInstruction, MInstruction, RInstruction, SBInstruction, SInstruction, SyscallInstruction,
-        UInstruction, UJInstruction,
+        IInstruction, Instruction, MInstruction, RInstruction, SBInstruction, SInstruction,
+        SyscallInstruction, UInstruction, UJInstruction,
     },
 };
+use ark_ff::Zero;
 use mina_curves::pasta::Fp;
+use rand::{CryptoRng, Rng, RngCore};
 use strum::EnumCount;
 
+pub fn dummy_env() -> Env<Fp> {
+    Env {
+        instruction_counter: 0,
+        memory: vec![(0, vec![0; PAGE_SIZE.try_into().unwrap()])],
+        last_memory_accesses: [0; 3],
+        memory_write_index: vec![(0, vec![0; PAGE_SIZE.try_into().unwrap()])],
+        last_memory_write_index_accesses: [0; 3],
+        registers: Registers::default(),
+        registers_write_index: Registers::default(),
+        scratch_state_idx: 0,
+        scratch_state: [Fp::zero(); SCRATCH_SIZE],
+        halt: false,
+        selector: INSTRUCTION_SET_SIZE,
+    }
+}
+
+pub fn generate_random_add_instruction<RNG: RngCore + CryptoRng>(rng: &mut RNG) -> [u8; 4] {
+    let opcode = 0b0110011;
+    let rd = rng.gen_range(0..32);
+    let funct3 = 0b000;
+    let rs1 = rng.gen_range(0..32);
+    let rs2 = rng.gen_range(0..32);
+    let funct2 = 0b00;
+    let funct5 = 0b00000;
+    let instruction = opcode
+        | (rd << 7)
+        | (funct3 << 12)
+        | (rs1 << 15)
+        | (rs2 << 20)
+        | (funct2 << 25)
+        | (funct5 << 27);
+    [
+        instruction as u8,
+        (instruction >> 8) as u8,
+        (instruction >> 16) as u8,
+        (instruction >> 24) as u8,
+    ]
+}
+
+#[test]
+pub fn test_instruction_decoding_add() {
+    let mut env: Env<Fp> = dummy_env();
+    let mut rng = o1_utils::tests::make_test_rng(None);
+    let instruction = generate_random_add_instruction(&mut rng);
+    env.memory[0].1[0] = instruction[0];
+    env.memory[0].1[1] = instruction[1];
+    env.memory[0].1[2] = instruction[2];
+    env.memory[0].1[3] = instruction[3];
+    let (opcode, _instruction) = env.decode_instruction();
+    assert_eq!(opcode, Instruction::RType(RInstruction::Add));
+}
+
 #[test]
 // Sanity check that we have as many selector as we have instructions
 fn test_regression_selectors_for_instructions() {