From 19ae021e3c221f9272dfd5a65e61625614c0d5a6 Mon Sep 17 00:00:00 2001
From: Jan Ferdinand Sauer <ferdinand@neptune.cash>
Date: Fri, 29 Sep 2023 19:10:52 +0200
Subject: [PATCH] deal with illegal arguments in test instruction explicitly

---
 triton-vm/src/instruction.rs | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/triton-vm/src/instruction.rs b/triton-vm/src/instruction.rs
index 873cb8169..929451da1 100644
--- a/triton-vm/src/instruction.rs
+++ b/triton-vm/src/instruction.rs
@@ -501,7 +501,7 @@ const fn all_instructions_without_args() -> [AnInstruction<BFieldElement>; Instr
         Push(BFIELD_ZERO),
         Divine,
         Dup(ST0),
-        Swap(ST1),
+        Swap(ST0),
         Nop,
         Skiz,
         Call(BFIELD_ZERO),
@@ -814,6 +814,7 @@ mod instruction_tests {
     #[test]
     fn instructions_act_on_op_stack_as_indicated() {
         for test_instruction in all_instructions_without_args() {
+            let test_instruction = replace_illegal_arguments_in_instruction(test_instruction);
             let (program, stack_size_before_test_instruction) =
                 construct_test_program_for_instruction(test_instruction);
             let stack_size_after_test_instruction = terminal_op_stack_size_for_program(program);
@@ -827,6 +828,15 @@ mod instruction_tests {
         }
     }
 
+    fn replace_illegal_arguments_in_instruction(
+        instruction: AnInstruction<BFieldElement>,
+    ) -> AnInstruction<BFieldElement> {
+        match instruction {
+            Swap(ST0) => Swap(ST1),
+            _ => instruction,
+        }
+    }
+
     fn construct_test_program_for_instruction(
         instruction: AnInstruction<BFieldElement>,
     ) -> (Program, usize) {