feat: add integration tests for bitshift operators

crates/nargo_cli/tests/test_data/bit_shifts/Nargo.toml

@@ -0,0 +1,5 @@
+[package]
+authors = [""]
+compiler_version = "0.1"
+
+[dependencies]

crates/nargo_cli/tests/test_data/bit_shifts/Prover.toml

@@ -0,0 +1,2 @@
+x = 64
+y = 1

crates/nargo_cli/tests/test_data/bit_shifts/src/main.nr

@@ -0,0 +1,26 @@
+fn main(x: u64, y: u64) {
+	let two: u64 = 2;
+	let three: u64 = 3;
+
+	// comptime shifts on comptime values
+	constrain two << 2 == 8;
+	constrain (two << 3) / 8 == two;
+	constrain (three >> 1) == 1;
+
+	// comptime shifts on runtime values
+	constrain x << 1 == 128;
+	constrain x >> 2 == 16;
+
+	// runtime shifts on comptime values
+	// These are currently unimplemented and panic with "ShiftLeft and ShiftRight operations with shifts which are only known at runtime are not yet implemented."
+	// See: https://github.com/noir-lang/noir/issues/1265
+	// constrain 64 << y == 128;
+	// constrain 64 >> y == 32;
+
+	// runtime shifts on runtime values
+	// These are currently unimplemented and panic with "ShiftLeft and ShiftRight operations with shifts which are only known at runtime are not yet implemented."
+	// See: https://github.com/noir-lang/noir/issues/1265
+	// constrain x << y == 128;
+	// constrain x >> y == 32;
+	constrain y == 1;
+}

crates/noirc_evaluator/src/ssa/acir_gen/operations/binary.rs

@@ -238,7 +238,7 @@ pub(crate) fn evaluate(
                 };
                 InternalVar::from(bitwise_result)
             }
-            BinaryOp::Shl | BinaryOp::Shr(_) => unreachable!("ICE: ShiftLeft and ShiftRight are replaced by multiplications and divisions in optimization pass."),
+            BinaryOp::Shl | BinaryOp::Shr(_) => todo!("ShiftLeft and ShiftRight operations with shifts which are only known at runtime are not yet implemented."),
             i @ BinaryOp::Assign => unreachable!("Invalid Instruction: {:?}", i),
         };
     Some(binary_output)