EIP-2315: Simple Subroutines for the EVM (#11629)

ethcore/src/trace/types/error.rs

@@ -34,6 +34,12 @@ pub enum Error {
     StackUnderflow,
     /// When execution would exceed defined Stack Limit
     OutOfStack,
+    /// When there is not enough subroutine stack elements to return from
+    SubStackUnderflow,
+    /// When execution would exceed defined subroutine Stack Limit
+    OutOfSubStack,
+    /// When the code walks into a subroutine, that is not allowed
+    InvalidSubEntry,
     /// When builtin contract failed on input data
     BuiltIn,
     /// Returned on evm internal error. Should never be ignored during development.
@@ -57,6 +63,9 @@ impl<'a> From<&'a VmError> for Error {
             VmError::BadInstruction { .. } => Error::BadInstruction,
             VmError::StackUnderflow { .. } => Error::StackUnderflow,
             VmError::OutOfStack { .. } => Error::OutOfStack,
+            VmError::SubStackUnderflow { .. } => Error::SubStackUnderflow,
+            VmError::OutOfSubStack { .. } => Error::OutOfSubStack,
+            VmError::InvalidSubEntry { .. } => Error::InvalidSubEntry,
             VmError::BuiltIn { .. } => Error::BuiltIn,
             VmError::Wasm { .. } => Error::Wasm,
             VmError::Internal(_) => Error::Internal,
@@ -82,7 +91,10 @@ impl fmt::Display for Error {
             BadInstruction => "Bad instruction",
             StackUnderflow => "Stack underflow",
             OutOfStack => "Out of stack",
+            SubStackUnderflow => "Subroutine stack underflow",
+            OutOfSubStack => "Subroutine stack overflow",
             BuiltIn => "Built-in failed",
+            InvalidSubEntry => "Invalid subroutine entry",
             Wasm => "Wasm runtime error",
             Internal => "Internal error",
             MutableCallInStaticContext => "Mutable Call In Static Context",
@@ -108,6 +120,9 @@ impl Encodable for Error {
             Wasm => 8,
             OutOfBounds => 9,
             Reverted => 10,
+            SubStackUnderflow => 11,
+            OutOfSubStack => 12,
+            InvalidSubEntry => 13,
         };
 
         s.append_internal(&value);
@@ -130,6 +145,9 @@ impl Decodable for Error {
             8 => Ok(Wasm),
             9 => Ok(OutOfBounds),
             10 => Ok(Reverted),
+            11 => Ok(SubStackUnderflow),
+            12 => Ok(OutOfSubStack),
+            13 => Ok(InvalidSubEntry),
             _ => Err(DecoderError::Custom("Invalid error type")),
         }
     }