From 48149f93d153fa8840c72c71763e9c8af86d604a Mon Sep 17 00:00:00 2001
From: Dmitry Vagner <dmitry.vagner@gmail.com>
Date: Mon, 5 Dec 2022 22:50:45 -0800
Subject: [PATCH] inverse

---
 evm/src/cpu/kernel/aggregator.rs                    |  2 +-
 .../curve/bn254/curve_arithmetic/miller_loop.asm    |  2 +-
 .../field_arithmetic/{moddiv.asm => inverse.asm}    | 13 +++++++++++++
 evm/src/cpu/kernel/interpreter.rs                   |  3 ++-
 4 files changed, 17 insertions(+), 3 deletions(-)
 rename evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/{moddiv.asm => inverse.asm} (62%)

diff --git a/evm/src/cpu/kernel/aggregator.rs b/evm/src/cpu/kernel/aggregator.rs
index bb2dce92..c0f8de77 100644
--- a/evm/src/cpu/kernel/aggregator.rs
+++ b/evm/src/cpu/kernel/aggregator.rs
@@ -29,7 +29,7 @@ pub(crate) fn combined_kernel() -> Kernel {
         include_str!("asm/curve/bn254/curve_arithmetic/curve_mul.asm"),
         include_str!("asm/curve/bn254/curve_arithmetic/miller_loop.asm"),
         include_str!("asm/curve/bn254/curve_arithmetic/tate_pairing.asm"),
-        include_str!("asm/curve/bn254/field_arithmetic/moddiv.asm"),
+        include_str!("asm/curve/bn254/field_arithmetic/inverse.asm"),
         include_str!("asm/curve/bn254/field_arithmetic/field_macros.asm"),
         include_str!("asm/curve/bn254/field_arithmetic/fp6_mul.asm"),
         include_str!("asm/curve/bn254/field_arithmetic/fp12_mul.asm"),
diff --git a/evm/src/cpu/kernel/asm/curve/bn254/curve_arithmetic/miller_loop.asm b/evm/src/cpu/kernel/asm/curve/bn254/curve_arithmetic/miller_loop.asm
index 3f625d16..2b630186 100644
--- a/evm/src/cpu/kernel/asm/curve/bn254/curve_arithmetic/miller_loop.asm
+++ b/evm/src/cpu/kernel/asm/curve/bn254/curve_arithmetic/miller_loop.asm
@@ -70,7 +70,7 @@ miller_end:
 
 miller_one:
     // stack:               0xnm, times, O, P, Q, out, retdest
-    PUSH 0x10  DUP2  LT       
+    DUP1  %gt_const(0x10) 
     // stack:        skip?, 0xnm, times, O, P, Q, out, retdest
     %jumpi(miller_zero)
     // stack:               0xnm, times, O, P, Q, out, retdest
diff --git a/evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/moddiv.asm b/evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/inverse.asm
similarity index 62%
rename from evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/moddiv.asm
rename to evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/inverse.asm
index 578eddae..6d5169e8 100644
--- a/evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/moddiv.asm
+++ b/evm/src/cpu/kernel/asm/curve/bn254/field_arithmetic/inverse.asm
@@ -20,3 +20,16 @@
     %assert_eq_const(1)
     // stack:           x^-1
 %endmacro
+
+// Non-deterministically provide the inverse modulo N.
+%macro inverse
+    // stack: x
+    PROVER_INPUT(ff::bn254_base::inverse)
+    // stack: x^-1 , x
+    SWAP1  DUP2
+    // stack: x^-1 , x, x^-1
+    MULFP254
+    // stack: x^-1 * x, x^-1
+    %assert_eq_const(1)
+    // stack:           x^-1
+%endmacro
diff --git a/evm/src/cpu/kernel/interpreter.rs b/evm/src/cpu/kernel/interpreter.rs
index b63911ed..f075b11d 100644
--- a/evm/src/cpu/kernel/interpreter.rs
+++ b/evm/src/cpu/kernel/interpreter.rs
@@ -388,7 +388,8 @@ impl<'a> Interpreter<'a> {
     // should be changed to the proper implementation prime
 
     fn bn_base_order_() -> U256 {
-        U256::from_str("0x30644e72e131a029b85045b68181585d97816a916871ca8d3c208c16d87cfd47").unwrap()
+        U256::from_str("0x30644e72e131a029b85045b68181585d97816a916871ca8d3c208c16d87cfd47")
+            .unwrap()
     }
 
     fn run_addfp254(&mut self) {