perf(eof): avoid some allocations

Author: DaniPopes

crates/interpreter/src/interpreter/analysis.rs

@@ -1,17 +1,16 @@
-use revm_primitives::{eof::EofDecodeError, HashSet};
-
 use crate::{
     instructions::utility::{read_i16, read_u16},
     opcode,
     primitives::{
         bitvec::prelude::{bitvec, BitVec, Lsb0},
-        eof::TypesSection,
+        eof::{EofDecodeError, TypesSection},
         legacy::JumpTable,
-        Bytecode, Bytes, Eof, LegacyAnalyzedBytecode,
+        Bytecode, Bytes, Eof, HashSet, LegacyAnalyzedBytecode,
     },
     OPCODE_INFO_JUMPTABLE, STACK_LIMIT,
 };
-use std::{sync::Arc, vec, vec::Vec};
+use core::convert::identity;
+use std::{borrow::Cow, sync::Arc, vec, vec::Vec};
 
 const EOF_NON_RETURNING_FUNCTION: u8 = 0x80;
 
@@ -66,33 +65,36 @@ fn analyze(code: &[u8]) -> JumpTable {
     JumpTable(Arc::new(jumps))
 }
 
-pub fn validate_raw_eof(bytecode: Bytes) -> Result<Eof, EofError> {
-    let eof = Eof::decode(bytecode)?;
+/// Decodes `raw` into an [`Eof`] container and validates it.
+pub fn validate_raw_eof(raw: Bytes) -> Result<Eof, EofError> {
+    let eof = Eof::decode(raw)?;
     validate_eof(&eof)?;
     Ok(eof)
 }
 
-/// Validate Eof structures.
+/// Fully validates an [`Eof`] container.
 pub fn validate_eof(eof: &Eof) -> Result<(), EofError> {
-    // clone is cheap as it is Bytes and a header.
-    let mut queue = vec![eof.clone()];
+    if eof.body.container_section.is_empty() {
+        validate_eof_codes(eof)?;
+        return Ok(());
+    }
 
-    while let Some(eof) = queue.pop() {
-        // iterate over types
+    let mut stack = Vec::with_capacity(4);
+    stack.push(Cow::Borrowed(eof));
+    while let Some(eof) = stack.pop() {
+        // Validate the current container.
         validate_eof_codes(&eof)?;
-        // iterate over containers, convert them to Eof and add to analyze_eof
-        for container in eof.body.container_section {
-            queue.push(Eof::decode(container)?);
+        // Decode subcontainers and push them to the stack.
+        for container in &eof.body.container_section {
+            stack.push(Cow::Owned(Eof::decode(container.clone())?));
         }
     }
 
-    // Eof is valid
     Ok(())
 }
 
-/// Validate EOF
+/// Validates an [`Eof`] structure, without recursing into containers.
 pub fn validate_eof_codes(eof: &Eof) -> Result<(), EofValidationError> {
-    let mut queued_codes = vec![false; eof.body.code_section.len()];
     if eof.body.code_section.len() != eof.body.types_section.len() {
         return Err(EofValidationError::InvalidTypesSection);
     }
@@ -101,8 +103,6 @@ pub fn validate_eof_codes(eof: &Eof) -> Result<(), EofValidationError> {
         // no code sections. This should be already checked in decode.
         return Err(EofValidationError::NoCodeSections);
     }
-    // first section is default one.
-    queued_codes[0] = true;
 
     // the first code section must have a type signature
     // (0, 0x80, max_stack_height) (0 inputs non-returning function)
@@ -111,11 +111,16 @@ pub fn validate_eof_codes(eof: &Eof) -> Result<(), EofValidationError> {
         return Err(EofValidationError::InvalidTypesSection);
     }
 
+    // first section is default one.
+    let mut code_sections_accessed = vec![false; eof.body.code_section.len()];
+    code_sections_accessed[0] = true;
+
     // start validation from code section 0.
-    let mut queue = vec![0];
-    while let Some(index) = queue.pop() {
+    let mut stack = Vec::with_capacity(16);
+    stack.push(0);
+    while let Some(index) = stack.pop() {
         let code = &eof.body.code_section[index];
-        let accessed_codes = validate_eof_code(
+        let accessed = validate_eof_code(
             code,
             eof.header.data_size as usize,
             index,
@@ -124,15 +129,15 @@ pub fn validate_eof_codes(eof: &Eof) -> Result<(), EofValidationError> {
         )?;
 
         // queue accessed codes.
-        accessed_codes.into_iter().for_each(|i| {
-            if !queued_codes[i] {
-                queued_codes[i] = true;
-                queue.push(i);
+        accessed.into_iter().for_each(|i| {
+            if !code_sections_accessed[i] {
+                code_sections_accessed[i] = true;
+                stack.push(i);
             }
         });
     }
     // iterate over accessed codes and check if all are accessed.
-    if queued_codes.into_iter().any(|x| !x) {
+    if !code_sections_accessed.into_iter().all(identity) {
         return Err(EofValidationError::CodeSectionNotAccessed);
     }
 

crates/primitives/src/bytecode/eof.rs

@@ -21,13 +21,9 @@ pub const EOF_MAGIC: u16 = 0xEF00;
 /// EOF magic number in array form.
 pub static EOF_MAGIC_BYTES: Bytes = bytes!("ef00");
 
-/// EOF - Ethereum Object Format.
+/// Ethereum Object Format (EOF) container.
 ///
-/// It consist of a header, body and raw original bytes Specified in EIP.
-/// Most of body contain Bytes so it references to the raw bytes.
-///
-/// If there is a need to create new EOF from scratch, it is recommended to use `EofBody` and
-/// use `encode` function to create full [`Eof`] object.
+/// It consists of a header, body and the raw original bytes.
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Eof {
@@ -42,7 +38,7 @@ impl Default for Eof {
             // types section with zero inputs, zero outputs and zero max stack size.
             types_section: vec![TypesSection::default()],
             // One code section with a STOP byte.
-            code_section: vec![[0x00].into()],
+            code_section: vec![Bytes::from_static(&[0x00])],
             container_section: vec![],
             data_section: Bytes::new(),
             is_data_filled: true,
@@ -52,6 +48,11 @@ impl Default for Eof {
 }
 
 impl Eof {
+    /// Creates a new EOF container from the given body.
+    pub fn new(body: EofBody) -> Self {
+        body.into_eof()
+    }
+
     /// Returns len of the header and body in bytes.
     pub fn size(&self) -> usize {
         self.header.size() + self.header.body_size()
@@ -88,22 +89,15 @@ impl Eof {
 
     /// Decode EOF that have additional dangling bytes.
     /// Assume that data section is fully filled.
-    pub fn decode_dangling(mut eof: Bytes) -> Result<(Self, Bytes), EofDecodeError> {
-        let (header, _) = EofHeader::decode(&eof)?;
+    pub fn decode_dangling(mut raw: Bytes) -> Result<(Self, Bytes), EofDecodeError> {
+        let (header, _) = EofHeader::decode(&raw)?;
         let eof_size = header.body_size() + header.size();
-        if eof_size > eof.len() {
+        if eof_size > raw.len() {
             return Err(EofDecodeError::MissingInput);
         }
-        let dangling_data = eof.split_off(eof_size);
-        let body = EofBody::decode(&eof, &header)?;
-        Ok((
-            Self {
-                header,
-                body,
-                raw: eof,
-            },
-            dangling_data,
-        ))
+        let dangling_data = raw.split_off(eof_size);
+        let body = EofBody::decode(&raw, &header)?;
+        Ok((Self { header, body, raw }, dangling_data))
     }
 
     /// Decode EOF from raw bytes.

crates/primitives/src/bytecode/eof/body.rs

@@ -2,9 +2,11 @@ use super::{Eof, EofDecodeError, EofHeader, TypesSection};
 use crate::Bytes;
 use std::vec::Vec;
 
-/// EOF Body, contains types, code, container and data sections.
+/// EOF container body.
 ///
-/// Can be used to create new EOF object.
+/// Contains types, code, container and data sections.
+///
+/// Can be used to create a new EOF container using the [`into_eof`](EofBody::into_eof) method.
 #[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct EofBody {
@@ -16,12 +18,12 @@ pub struct EofBody {
 }
 
 impl EofBody {
-    // Get code section
+    /// Returns the code section at the given index.
     pub fn code(&self, index: usize) -> Option<&Bytes> {
         self.code_section.get(index)
     }
 
-    /// Create EOF from body.
+    /// Creates an EOF container from this body.
     pub fn into_eof(self) -> Eof {
         // TODO add bounds checks.
         let header = EofHeader {
@@ -46,7 +48,7 @@ impl EofBody {
         }
     }
 
-    /// Encode Body into buffer.
+    /// Encodes this body into the given buffer.
     pub fn encode(&self, buffer: &mut Vec<u8>) {
         for types_section in &self.types_section {
             types_section.encode(buffer);
@@ -63,7 +65,7 @@ impl EofBody {
         buffer.extend_from_slice(&self.data_section);
     }
 
-    /// Decode EOF body from buffer and Header.
+    /// Decodes an EOF container body from the given buffer and header.
     pub fn decode(input: &Bytes, header: &EofHeader) -> Result<Self, EofDecodeError> {
         let header_len = header.size();
         let partial_body_len =