new(tests): EOF - EIP-663: EXCHANGE opcode (#544)

* new(test): add tests for EOF/EIP-663 DUPN SWAPN

* improve code generation

* chore(ci): Update workflow actions to use Node.js 20 versions (#527)

* chore(ci): Update workflow actions to use Node.js 20 versions.

* chore: Add changelog.

* Add --traces support to besu (#511)

Add support for adding traces to output when using Besu.

Signed-off-by: Danno Ferrin <[email protected]>

* feat(fw): call `evmone-eofparse` on generated EOF fixtures in fill (#519)

Co-authored-by: Dimitry Kh <[email protected]>
Co-authored-by: danceratopz <[email protected]>

* docs(fix): small fix to tracing report in readme cf #511 (#539)

* fix EOF return stack tests

The tests were previously corrected against a bug in Besu,

Signed-off-by: Danno Ferrin <[email protected]>

* EXCHANGE

Exercise exchange operation

Signed-off-by: Danno Ferrin <[email protected]>

* speling

Signed-off-by: Danno Ferrin <[email protected]>

* move

Signed-off-by: Danno Ferrin <[email protected]>

* feat(fw): Add EXCHANGE encoder

* new(tests): EOF - EIP-663: Invalid container due to invalid exchange

---------

Signed-off-by: Danno Ferrin <[email protected]>
Co-authored-by: Paweł Bylica <[email protected]>
Co-authored-by: spencer <[email protected]>
Co-authored-by: Mario Vega <[email protected]>
Co-authored-by: Dimitry Kh <[email protected]>
Co-authored-by: danceratopz <[email protected]>

src/ethereum_test_tools/tests/test_vm.py

@@ -261,6 +261,10 @@
         (Op.RJUMPV[0, 3, 6, 9], bytes.fromhex("e2030000000300060009")),
         (Op.RJUMPV[2, 0], bytes.fromhex("e20100020000")),
         (Op.RJUMPV[b"\x02\x00\x02\xFF\xFF"], bytes.fromhex("e2020002ffff")),
+        (Op.EXCHANGE[0x2 + 0x0, 0x3 + 0x0], bytes.fromhex("e800")),
+        (Op.EXCHANGE[0x2 + 0x0, 0x3 + 0xF], bytes.fromhex("e80f")),
+        (Op.EXCHANGE[0x2 + 0xF, 0x3 + 0xF + 0x0], bytes.fromhex("e8f0")),
+        (Op.EXCHANGE[0x2 + 0xF, 0x3 + 0xF + 0xF], bytes.fromhex("e8ff")),
     ],
 )
 def test_opcodes(opcodes: bytes, expected: bytes):

src/ethereum_test_tools/vm/opcode.py

@@ -172,7 +172,10 @@ def __getitem__(
         data_portion = bytes()
 
         if self.data_portion_formatter is not None:
-            data_portion = self.data_portion_formatter(*args)
+            if len(args) == 1 and isinstance(args[0], Iterable) and not isinstance(args[0], bytes):
+                data_portion = self.data_portion_formatter(*args[0])
+            else:
+                data_portion = self.data_portion_formatter(*args)
         elif self.data_portion_length > 0:
             # For opcodes with a data portion, the first argument is the data and the rest of the
             # arguments form the stack.
@@ -253,8 +256,10 @@ def __call__(
             raise ValueError("Opcode with data portion requires at least one argument")
         if self.data_portion_formatter is not None:
             data_portion_arg = args.pop(0)
-            assert isinstance(data_portion_arg, Iterable)
-            data_portion = self.data_portion_formatter(*data_portion_arg)
+            if isinstance(data_portion_arg, Iterable) and not isinstance(data_portion_arg, bytes):
+                data_portion = self.data_portion_formatter(*data_portion_arg)
+            else:
+                data_portion = self.data_portion_formatter(data_portion_arg)
         elif self.data_portion_length > 0:
             # For opcodes with a data portion, the first argument is the data and the rest of the
             # arguments form the stack.
@@ -398,6 +403,27 @@ def _rjumpv_encoder(*args: int | bytes | Iterable[int]) -> bytes:
     )
 
 
+def _exchange_encoder(*args: int) -> bytes:
+    assert 1 <= len(args) <= 2, f"Exchange opcode requires one or two arguments, got {len(args)}"
+    if len(args) == 1:
+        return int.to_bytes(args[0], 1, "big")
+    # n = imm >> 4 + 1
+    # m = imm & 0xF + 1
+    # x = n + 1
+    # y = n + m + 1
+    # ...
+    # n = x - 1
+    # m = y - x
+    # m = y - n - 1
+    x, y = args
+    assert 2 <= x <= 0x11
+    assert x + 1 <= y <= x + 0x10
+    n = x - 1
+    m = y - x
+    imm = (n - 1) << 4 | m - 1
+    return int.to_bytes(imm, 1, "big")
+
+
 class Opcodes(Opcode, Enum):
     """
     Enum containing all known opcodes.
@@ -4976,6 +5002,13 @@ class Opcodes(Opcode, Enum):
     Description
     ----
 
+    - deduct 3 gas
+    - read uint8 operand imm
+    - n = imm + 1
+    - n‘th (1-based) stack item is duplicated at the top of the stack
+    - Stack validation: stack_height >= n
+
+
     Inputs
     ----
 
@@ -4984,6 +5017,7 @@ class Opcodes(Opcode, Enum):
 
     Fork
     ----
+    EOF Fork
 
     Gas
     ----
@@ -5000,6 +5034,13 @@ class Opcodes(Opcode, Enum):
     Description
     ----
 
+    - deduct 3 gas
+    - read uint8 operand imm
+    - n = imm + 1
+    - n + 1th stack item is swapped with the top stack item (1-based).
+    - Stack validation: stack_height >= n + 1
+
+
     Inputs
     ----
 
@@ -5008,12 +5049,48 @@ class Opcodes(Opcode, Enum):
 
     Fork
     ----
+    EOF Fork
 
     Gas
     ----
 
     """
 
+    EXCHANGE = Opcode(0xE8, data_portion_formatter=_exchange_encoder)
+    """
+    !!! Note: This opcode is under development
+
+    EXCHANGE[x, y]
+    ----
+
+    Description
+    ----
+    Exchanges two stack positions.  Two nybbles, n is high 4 bits + 1, then  m is 4 low bits + 1.
+    Exchanges tne n+1'th item with the n + m + 1 item.
+
+    Inputs x and y when the opcode is used as `EXCHANGE[x, y]`, are equal to:
+    - x = n + 1
+    - y = n + m + 1
+    Which each equals to 1-based stack positions swapped.
+
+    Inputs
+    ----
+    n + m + 1, or ((imm >> 4) + (imm &0x0F) + 3) from the raw immediate,
+
+    Outputs
+    ----
+    n + m + 1, or ((imm >> 4) + (imm &0x0F) + 3) from the raw immediate,
+
+    Fork
+    ----
+    EOF_FORK
+
+    Gas
+    ----
+    3
+
+    """
+
     CREATE3 = Opcode(0xEC, popped_stack_items=4, pushed_stack_items=1, data_portion_length=1)
     """
     !!! Note: This opcode is under development

tests/prague/eip7692_eof_v1/eip663_dupn_swapn_exchange/test_exchange.py

@@ -0,0 +1,118 @@
+"""
+abstract: Tests [EIP-663: SWAPN, DUPN and EXCHANGE instructions](https://eips.ethereum.org/EIPS/eip-663)
+    Tests for the EXCHANGE instruction.
+"""  # noqa: E501
+
+import pytest
+
+from ethereum_test_tools import (
+    Account,
+    Environment,
+    EOFException,
+    EOFTestFiller,
+    StateTestFiller,
+    TestAddress,
+    Transaction,
+)
+from ethereum_test_tools.eof.v1 import Container, Section
+from ethereum_test_tools.eof.v1.constants import NON_RETURNING_SECTION
+from ethereum_test_tools.vm.opcode import Opcodes as Op
+
+from ..eip3540_eof_v1.spec import EOF_FORK_NAME
+from . import REFERENCE_SPEC_GIT_PATH, REFERENCE_SPEC_VERSION
+
+REFERENCE_SPEC_GIT_PATH = REFERENCE_SPEC_GIT_PATH
+REFERENCE_SPEC_VERSION = REFERENCE_SPEC_VERSION
+
+
+@pytest.mark.valid_from(EOF_FORK_NAME)
+def test_exchange_all_valid_immediates(
+    tx: Transaction,
+    state_test: StateTestFiller,
+):
+    """
+    Test case for all valid EXCHANGE immediates.
+    """
+    n = 256
+    s = 34
+    values = range(0x3E8, 0x3E8 + s)
+
+    eof_code = Container(
+        sections=[
+            Section.Code(
+                code=b"".join(Op.PUSH2(v) for v in values)
+                + b"".join(Op.EXCHANGE(x) for x in range(0, n))
+                + b"".join((Op.PUSH1(x) + Op.SSTORE) for x in range(0, s))
+                + Op.STOP,
+                code_inputs=0,
+                code_outputs=NON_RETURNING_SECTION,
+                max_stack_height=s + 1,
+            )
+        ],
+    )
+
+    pre = {
+        TestAddress: Account(balance=1_000_000_000),
+        tx.to: Account(code=eof_code),
+    }
+
+    # this does the same full-loop exchange
+    values_rotated = list(range(0x3E8, 0x3E8 + s))
+    for e in range(0, n):
+        a = (e >> 4) + 1
+        b = (e & 0x0F) + 1 + a
+        temp = values_rotated[a]
+        values_rotated[a] = values_rotated[b]
+        values_rotated[b] = temp
+
+    post = {tx.to: Account(storage=dict(zip(range(0, s), reversed(values_rotated))))}
+
+    state_test(
+        env=Environment(),
+        pre=pre,
+        post=post,
+        tx=tx,
+    )
+
+
+@pytest.mark.parametrize(
+    "stack_height,x,y",
+    [
+        # 2 and 3 are the lowest valid values for x and y, which translates to a
+        # zero immediate value.
+        pytest.param(0, 2, 3, id="stack_height=0_n=1_m=1"),
+        pytest.param(1, 2, 3, id="stack_height=1_n=1_m=1"),
+        pytest.param(2, 2, 3, id="stack_height=2_n=1_m=1"),
+        pytest.param(17, 2, 18, id="stack_height=17_n=1_m=16"),
+        pytest.param(17, 17, 18, id="stack_height=17_n=16_m=1"),
+        pytest.param(32, 17, 33, id="stack_height=32_n=16_m=16"),
+    ],
+)
+@pytest.mark.valid_from(EOF_FORK_NAME)
+def test_exchange_all_invalid_immediates(
+    eof_test: EOFTestFiller,
+    stack_height: int,
+    x: int,
+    y: int,
+):
+    """
+    Test case for all invalid EXCHANGE immediates.
+    """
+    eof_code = Container(
+        sections=[
+            Section.Code(
+                code=b"".join(Op.PUSH2(v) for v in range(stack_height))
+                + Op.EXCHANGE[x, y]
+                + Op.POP * stack_height
+                + Op.STOP,
+                code_inputs=0,
+                code_outputs=NON_RETURNING_SECTION,
+                max_stack_height=stack_height,
+            )
+        ],
+    )
+
+    eof_test(
+        data=eof_code,
+        expect_exception=EOFException.STACK_UNDERFLOW,
+    )

whitelist.txt

@@ -180,6 +180,7 @@ hyperledger
 iat
 ignoreRevsFile
 img
+imm
 immediates
 incrementing
 init