From 7482d1b4d356a6f4c906836535742387c6deb3cc Mon Sep 17 00:00:00 2001
From: Danny Willems <be.danny.willems@gmail.com>
Date: Wed, 20 Nov 2024 16:59:21 +0100
Subject: [PATCH] o1vm/riscv32: remove unused divmod

As for mul_hi_lo(_signed), the method is splitted as there are individual
instructions for div and mod.
---
 o1vm/src/interpreters/riscv32im/constraints.rs | 13 -------------
 o1vm/src/interpreters/riscv32im/interpreter.rs | 16 ----------------
 o1vm/src/interpreters/riscv32im/witness.rs     | 18 ------------------
 3 files changed, 47 deletions(-)

diff --git a/o1vm/src/interpreters/riscv32im/constraints.rs b/o1vm/src/interpreters/riscv32im/constraints.rs
index 9fbdb8fbc8..2b02d708eb 100644
--- a/o1vm/src/interpreters/riscv32im/constraints.rs
+++ b/o1vm/src/interpreters/riscv32im/constraints.rs
@@ -389,19 +389,6 @@ impl<Fp: Field> InterpreterEnv for Env<Fp> {
         self.variable(position)
     }
 
-    unsafe fn divmod(
-        &mut self,
-        _x: &Self::Variable,
-        _y: &Self::Variable,
-        position_quotient: Self::Position,
-        position_remainder: Self::Position,
-    ) -> (Self::Variable, Self::Variable) {
-        (
-            self.variable(position_quotient),
-            self.variable(position_remainder),
-        )
-    }
-
     unsafe fn count_leading_zeros(
         &mut self,
         _x: &Self::Variable,
diff --git a/o1vm/src/interpreters/riscv32im/interpreter.rs b/o1vm/src/interpreters/riscv32im/interpreter.rs
index 0222924c78..c7a5e3bc17 100644
--- a/o1vm/src/interpreters/riscv32im/interpreter.rs
+++ b/o1vm/src/interpreters/riscv32im/interpreter.rs
@@ -1313,22 +1313,6 @@ pub trait InterpreterEnv {
         position: Self::Position,
     ) -> Self::Variable;
 
-    /// Returns `(x / y, x % y)`, storing the results in `position_quotient` and
-    /// `position_remainder` respectively.
-    ///
-    /// # Safety
-    ///
-    /// There are no constraints on the returned values; callers must manually add constraints to
-    /// ensure that the pair of returned values correspond to the given values `x` and `y`, and
-    /// that they fall within the desired range.
-    unsafe fn divmod(
-        &mut self,
-        x: &Self::Variable,
-        y: &Self::Variable,
-        position_quotient: Self::Position,
-        position_remainder: Self::Position,
-    ) -> (Self::Variable, Self::Variable);
-
     /// Returns the number of leading 0s in `x`, storing the result in `position`.
     ///
     /// # Safety
diff --git a/o1vm/src/interpreters/riscv32im/witness.rs b/o1vm/src/interpreters/riscv32im/witness.rs
index 8a1502c6ea..61d2868886 100644
--- a/o1vm/src/interpreters/riscv32im/witness.rs
+++ b/o1vm/src/interpreters/riscv32im/witness.rs
@@ -557,24 +557,6 @@ impl<Fp: Field> InterpreterEnv for Env<Fp> {
         res
     }
 
-    unsafe fn divmod(
-        &mut self,
-        x: &Self::Variable,
-        y: &Self::Variable,
-        position_quotient: Self::Position,
-        position_remainder: Self::Position,
-    ) -> (Self::Variable, Self::Variable) {
-        let x: u32 = (*x).try_into().unwrap();
-        let y: u32 = (*y).try_into().unwrap();
-        let q = x / y;
-        let r = x % y;
-        let q = q as u64;
-        let r = r as u64;
-        self.write_column(position_quotient, q);
-        self.write_column(position_remainder, r);
-        (q, r)
-    }
-
     unsafe fn count_leading_zeros(
         &mut self,
         x: &Self::Variable,