diff --git a/VMTests.md b/VMTests.md index 540ba3e0e..6ad20d4b0 100644 --- a/VMTests.md +++ b/VMTests.md @@ -132,7 +132,7 @@ VMTests + mul5.json OK + mul6.json OK + mul7.json OK -- mulUnderFlow.json Fail ++ mulUnderFlow.json OK + mulmod0.json OK + mulmod1.json OK + mulmod1_overflow.json OK @@ -163,7 +163,7 @@ VMTests + sdivByZero0.json OK + sdivByZero1.json OK + sdivByZero2.json OK -- sdiv_dejavu.json Fail ++ sdiv_dejavu.json OK + sdiv_i256min.json OK + sdiv_i256min2.json OK + sdiv_i256min3.json OK @@ -198,7 +198,7 @@ VMTests + sub3.json OK + sub4.json OK ``` -OK: 186/195 Fail: 8/195 Skip: 1/195 +OK: 188/195 Fail: 6/195 Skip: 1/195 ## vmBitwiseLogicOperation ```diff + and0.json OK diff --git a/src/vm/stack.nim b/src/vm/stack.nim index 359282c5c..111b0ac9c 100644 --- a/src/vm/stack.nim +++ b/src/vm/stack.nim @@ -75,28 +75,31 @@ proc push*(stack: var Stack, value: Bytes) = stack.values.add(value.toType(UInt256)) proc internalPop(stack: var Stack, numItems: int): seq[UInt256] = - if len(stack) < numItems: - result = @[] - else: - result = stack.values[^numItems .. ^1] - stack.values = stack.values[0 ..< ^numItems] + # TODO: it is very inefficient to allocate a seq + assert numItems <= stack.len + result = stack.values[^numItems .. ^1] + stack.values = stack.values[0 ..< ^numItems] proc internalPop(stack: var Stack, numItems: int, T: typedesc): seq[T] = + # TODO: it is very inefficient to allocate a seq + + assert numItems <= stack.len result = @[] - if len(stack) < numItems: - return for z in 0 ..< numItems: var value = stack.values.pop() result.add(toType(value, T)) -template ensurePop(elements: untyped, a: untyped): untyped = - if len(`elements`) < `a`: - raise newException(InsufficientStack, "No stack items") +proc ensurePop(elements: seq|Stack, a: int) = + let num = elements.len + let expected = a + if num < expected: + raise newException(InsufficientStack, + &"Stack underflow: expected {expected} elements, got {num} instead.") proc popInt*(stack: var Stack): UInt256 = + ensurePop(stack, 1) var elements = stack.internalPop(1, UInt256) - ensurePop(elements, 1) result = elements[0] macro internalPopTuple(numItems: static[int]): untyped = @@ -110,6 +113,8 @@ macro internalPopTuple(numItems: static[int]): untyped = result = quote: proc `name`*(`stackNode`: var Stack, `t`: typedesc): `typ` result[^1] = nnkStmtList.newTree() + result[^1].add quote do: + ensurePop(`stackNode`, `numItems`) for z in 0 ..< numItems: var zNode = newLit(z) var element = quote: diff --git a/tests/test_stack.nim b/tests/test_stack.nim index cb128599e..c5ae63f79 100644 --- a/tests/test_stack.nim +++ b/tests/test_stack.nim @@ -93,3 +93,12 @@ suite "stack": var stack = newStack() expect(InsufficientStack): stack.dup(0) + + test "binary operations raises InsufficientStack appropriately": + # https://github.com/status-im/nimbus/issues/31 + # ./tests/fixtures/VMTests/vmArithmeticTest/mulUnderFlow.json + + var stack = newStack() + stack.push(123) + expect(InsufficientStack): + discard stack.popInt(2)