fixed, simplifications, and MiniAlloc

Makefile

@@ -341,7 +341,7 @@ $(output_latest)/user_host.wasm: $(DEP_PREDICATE) $(wasm_lib_user_host) $(rust_p
 	cargo build --manifest-path arbitrator/wasm-libraries/Cargo.toml --release --target wasm32-wasi --package user-host
 	install arbitrator/wasm-libraries/$(wasm32_wasi)/user_host.wasm $@
 
-$(output_latest)/program_exec.wasm: $(DEP_PREDICATE) $(call wasm_lib_deps,user-host) $(rust_prover_files) .make/machines
+$(output_latest)/program_exec.wasm: $(DEP_PREDICATE) $(call wasm_lib_deps,program-exec) $(rust_prover_files) .make/machines
 	cargo build --manifest-path arbitrator/wasm-libraries/Cargo.toml --release --target wasm32-wasi --package program-exec
 	install arbitrator/wasm-libraries/$(wasm32_wasi)/program_exec.wasm $@
 

arbcompress/compress_wasm.go

@@ -1,4 +1,4 @@
-// Copyright 2021-2022, Offchain Labs, Inc.
+// Copyright 2021-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/nitro/blob/master/LICENSE
 
 //go:build wasm
@@ -22,7 +22,9 @@ func brotliDecompress(inBuf unsafe.Pointer, inBufLen uint32, outBuf unsafe.Point
 func Decompress(input []byte, maxSize int) ([]byte, error) {
 	outBuf := make([]byte, maxSize)
 	outLen := uint32(len(outBuf))
-	status := brotliDecompress(arbutil.SliceToUnsafePointer(input), uint32(len(input)), arbutil.SliceToUnsafePointer(outBuf), unsafe.Pointer(&outLen))
+	status := brotliDecompress(
+		arbutil.SliceToUnsafePointer(input), uint32(len(input)), arbutil.SliceToUnsafePointer(outBuf), unsafe.Pointer(&outLen),
+	)
 	if status != BrotliSuccess {
 		return nil, fmt.Errorf("failed decompression")
 	}
@@ -33,7 +35,12 @@ func compressLevel(input []byte, level uint32) ([]byte, error) {
 	maxOutSize := compressedBufferSizeFor(len(input))
 	outBuf := make([]byte, maxOutSize)
 	outLen := uint32(len(outBuf))
-	status := brotliCompress(arbutil.SliceToUnsafePointer(input), uint32(len(input)), arbutil.SliceToUnsafePointer(outBuf), unsafe.Pointer(&outLen), level, WINDOW_SIZE)
+	status := brotliCompress(
+		arbutil.SliceToUnsafePointer(input), uint32(len(input)),
+		arbutil.SliceToUnsafePointer(outBuf), unsafe.Pointer(&outLen),
+		level,
+		WINDOW_SIZE,
+	)
 	if status != BrotliSuccess {
 		return nil, fmt.Errorf("failed compression")
 	}

arbitrator/arbutil/src/evm/api.rs

@@ -48,17 +48,17 @@ pub enum EvmApiMethod {
     CaptureHostIO,
 }
 
-// This offset is added to EvmApiMethod when sending a request
-// in WASM - program done is also indicated by a "request", with the
-// id below that offset, indicating program status
+/// This offset is added to EvmApiMethod when sending a request
+/// in WASM - program done is also indicated by a "request", with the
+/// id below that offset, indicating program status
 pub const EVM_API_METHOD_REQ_OFFSET: u32 = 0x10000000;
 
-// note: clone should not clone actual data, just the reader
+/// note: clone should not clone actual data, just the reader
 pub trait DataReader: Clone + Send + 'static {
     fn slice(&self) -> &[u8];
 }
 
-// simple implementation for DataReader, in case data comes from a Vec
+/// simple implementation for DataReader, in case data comes from a Vec
 #[derive(Clone, Debug)]
 pub struct VecReader(Arc<Vec<u8>>);
 

arbitrator/arbutil/src/evm/req.rs

@@ -11,7 +11,7 @@ use crate::{
 use eyre::{bail, eyre, Result};
 
 pub trait RequestHandler<D: DataReader>: Send + 'static {
-    fn handle_request(&mut self, _req_type: EvmApiMethod, _req_data: &[u8]) -> (Vec<u8>, D, u64);
+    fn handle_request(&mut self, req_type: EvmApiMethod, req_data: &[u8]) -> (Vec<u8>, D, u64);
 }
 
 pub struct EvmApiRequestor<D: DataReader, H: RequestHandler<D>> {

arbitrator/arbutil/src/lib.rs

@@ -1,4 +1,4 @@
-// Copyright 2022-2023, Offchain Labs, Inc.
+// Copyright 2022-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/OffchainLabs/nitro/blob/master/LICENSE
 
 /// cbindgen:ignore
@@ -12,6 +12,7 @@ pub mod pricing;
 pub mod types;
 
 pub use color::{Color, DebugColor};
+use num_traits::Unsigned;
 pub use types::{Bytes20, Bytes32};
 
 /// Puts an arbitrary type on the heap.
@@ -21,7 +22,13 @@ pub fn heapify<T>(value: T) -> *mut T {
 }
 
 /// Equivalent to &[start..offset], but truncates when out of bounds rather than panicking.
-pub fn slice_with_runoff<T>(data: &impl AsRef<[T]>, start: usize, end: usize) -> &[T] {
+pub fn slice_with_runoff<T, I>(data: &impl AsRef<[T]>, start: I, end: I) -> &[T]
+where
+    I: TryInto<usize> + Unsigned,
+{
+    let start = start.try_into().unwrap_or(usize::MAX);
+    let end = end.try_into().unwrap_or(usize::MAX);
+
     let data = data.as_ref();
     if start >= data.len() || end < start {
         return &[];
@@ -32,12 +39,12 @@ pub fn slice_with_runoff<T>(data: &impl AsRef<[T]>, start: usize, end: usize) ->
 #[test]
 fn test_limit_vec() {
     let testvec = vec![0, 1, 2, 3];
-    assert_eq!(slice_with_runoff(&testvec, 4, 4), &testvec[0..0]);
-    assert_eq!(slice_with_runoff(&testvec, 1, 0), &testvec[0..0]);
-    assert_eq!(slice_with_runoff(&testvec, 0, 0), &testvec[0..0]);
-    assert_eq!(slice_with_runoff(&testvec, 0, 1), &testvec[0..1]);
-    assert_eq!(slice_with_runoff(&testvec, 1, 3), &testvec[1..3]);
-    assert_eq!(slice_with_runoff(&testvec, 0, 4), &testvec[0..4]);
-    assert_eq!(slice_with_runoff(&testvec, 0, 5), &testvec[0..4]);
+    assert_eq!(slice_with_runoff(&testvec, 4_u32, 4), &testvec[0..0]);
+    assert_eq!(slice_with_runoff(&testvec, 1_u16, 0), &testvec[0..0]);
+    assert_eq!(slice_with_runoff(&testvec, 0_u64, 0), &testvec[0..0]);
+    assert_eq!(slice_with_runoff(&testvec, 0_u32, 1), &testvec[0..1]);
+    assert_eq!(slice_with_runoff(&testvec, 1_u64, 3), &testvec[1..3]);
+    assert_eq!(slice_with_runoff(&testvec, 0_u16, 4), &testvec[0..4]);
+    assert_eq!(slice_with_runoff(&testvec, 0_u8, 5), &testvec[0..4]);
     assert_eq!(slice_with_runoff(&testvec, 2, usize::MAX), &testvec[2..4]);
 }

arbitrator/jit/src/program.rs

@@ -121,8 +121,8 @@ pub fn start_program(mut env: WasmEnvMut, module: u32) -> Result<u32, Escape> {
     Ok(msg.1)
 }
 
-// gets information about request according to id
-// request_id MUST be last request id returned from start_program or send_response
+/// gets information about request according to id
+/// request_id MUST be last request id returned from start_program or send_response
 pub fn get_request(mut env: WasmEnvMut, id: u32, len_ptr: GuestPtr) -> Result<u32, Escape> {
     let (mut mem, exec) = jit_env(&mut env);
     let thread = exec.wenv.threads.last_mut().unwrap();
@@ -148,8 +148,8 @@ pub fn get_request_data(mut env: WasmEnvMut, id: u32, data_ptr: GuestPtr) -> May
     Ok(())
 }
 
-// sets response for the next request made
-// id MUST be the id of last request made
+/// sets response for the next request made
+/// id MUST be the id of last request made
 pub fn set_response(
     mut env: WasmEnvMut,
     id: u32,
@@ -167,9 +167,9 @@ pub fn set_response(
     thread.set_response(id, result, raw_data, gas)
 }
 
-// sends previos response
-// MUST be called right after set_response to the same id
-// returns request_id for the next request
+/// sends previos response
+/// MUST be called right after set_response to the same id
+/// returns request_id for the next request
 pub fn send_response(mut env: WasmEnvMut, req_id: u32) -> Result<u32, Escape> {
     let (_, exec) = jit_env(&mut env);
     let thread = exec.wenv.threads.last_mut().unwrap();
@@ -182,7 +182,7 @@ pub fn send_response(mut env: WasmEnvMut, req_id: u32) -> Result<u32, Escape> {
     Ok(msg.1)
 }
 
-// removes the last created program
+/// removes the last created program
 pub fn pop(mut env: WasmEnvMut) -> MaybeEscape {
     let (_, exec) = jit_env(&mut env);
 
@@ -216,7 +216,6 @@ pub fn create_stylus_config(
 }
 
 /// Creates an `EvmData` handler from its component parts.
-///
 pub fn create_evm_data(
     mut env: WasmEnvMut,
     block_basefee_ptr: GuestPtr,

arbitrator/jit/src/stylus_backend.rs

@@ -1,4 +1,4 @@
-// Copyright 2023, Offchain Labs, Inc.
+// Copyright 2023-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/OffchainLabs/nitro/blob/master/LICENSE
 
 #![allow(clippy::too_many_arguments)]

arbitrator/prover/src/wavm.rs

@@ -171,7 +171,7 @@ pub enum Opcode {
     NewCoThread,
     /// pop cothread (cannot be called from cothread)
     PopCoThread,
-    /// switch to/from create cothread
+    /// switch between main and a cothread
     SwitchThread,
 }
 

arbitrator/prover/test-cases/go/main.go

@@ -1,4 +1,4 @@
-// Copyright 2021-2022, Offchain Labs, Inc.
+// Copyright 2021-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/nitro/blob/master/LICENSE
 
 package main

arbitrator/stylus/cbindgen.toml

@@ -10,4 +10,4 @@ extra_bindings = ["arbutil", "prover"]
 prefix_with_name = true
 
 [export]
-include = ["EvmApiMethod", "EvmApiMethodOffset"]
+include = ["EvmApiMethod"]

arbitrator/stylus/src/evm_api.rs

@@ -1,7 +1,7 @@
-// Copyright 2022-2023, Offchain Labs, Inc.
+// Copyright 2022-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/OffchainLabs/nitro/blob/master/LICENSE
 
-use crate::{GoSliceData, RustSlice, SendGoSliceData};
+use crate::{GoSliceData, RustSlice};
 use arbutil::evm::{
     api::{EvmApiMethod, EvmApiStatus, EVM_API_METHOD_REQ_OFFSET},
     req::RequestHandler,
@@ -15,8 +15,8 @@ pub struct NativeRequestHandler {
         data: *mut RustSlice,
         gas_cost: *mut u64,
         result: *mut GoSliceData,
-        raw_data: *mut SendGoSliceData,
-    ) -> EvmApiStatus, // value
+        raw_data: *mut GoSliceData,
+    ) -> EvmApiStatus,
     pub id: usize,
 }
 
@@ -26,14 +26,14 @@ macro_rules! ptr {
     };
 }
 
-impl RequestHandler<SendGoSliceData> for NativeRequestHandler {
+impl RequestHandler<GoSliceData> for NativeRequestHandler {
     fn handle_request(
         &mut self,
         req_type: EvmApiMethod,
         req_data: &[u8],
-    ) -> (Vec<u8>, SendGoSliceData, u64) {
-        let mut result = GoSliceData::default();
-        let mut raw_data = SendGoSliceData::default();
+    ) -> (Vec<u8>, GoSliceData, u64) {
+        let mut result = GoSliceData::null();
+        let mut raw_data = GoSliceData::null();
         let mut cost = 0;
         let status = unsafe {
             (self.handle_request_fptr)(

arbitrator/stylus/src/host.rs

@@ -12,7 +12,7 @@ use arbutil::{
     Color,
 };
 use caller_env::GuestPtr;
-use eyre::{eyre, Result};
+use eyre::Result;
 use prover::value::Value;
 use std::fmt::Display;
 use user_host_trait::UserHost;
@@ -70,17 +70,11 @@ impl<'a, DR: DataReader, A: EvmApi<DR>> UserHost<DR> for HostioInfo<'a, DR, A> {
         println!("{} {text}", "Stylus says:".yellow());
     }
 
-    fn trace(&mut self, name: &str, args: &[u8], outs: &[u8], start_ink: u64, end_ink: u64) {
+    fn trace(&mut self, name: &str, args: &[u8], outs: &[u8], end_ink: u64) {
+        let start_ink = self.start_ink;
         self.evm_api
             .capture_hostio(name, args, outs, start_ink, end_ink);
     }
-
-    fn start_ink(&self) -> Result<u64, Self::Err> {
-        if !self.env.evm_data.tracing {
-            return Err(eyre!("recording start ink when not captured").into());
-        }
-        Ok(self.start_ink)
-    }
 }
 
 macro_rules! hostio {

arbitrator/stylus/src/lib.rs

@@ -1,5 +1,6 @@
 // Copyright 2022-2024, Offchain Labs, Inc.
 // For license information, see https://github.com/OffchainLabs/nitro/blob/master/LICENSE
+
 use arbutil::{
     evm::{
         api::DataReader,
@@ -15,7 +16,7 @@ use eyre::ErrReport;
 use native::NativeInstance;
 use prover::programs::{prelude::*, StylusData};
 use run::RunProgram;
-use std::{marker::PhantomData, mem, ptr::null};
+use std::{marker::PhantomData, mem, ptr};
 
 pub use prover;
 
@@ -34,20 +35,23 @@ mod benchmarks;
 #[derive(Clone, Copy)]
 #[repr(C)]
 pub struct GoSliceData {
-    ptr: *const u8, // stored as pointer for GO
+    /// Points to data owned by Go.
+    ptr: *const u8,
+    /// The length in bytes.
     len: usize,
 }
 
-impl Default for GoSliceData {
-    fn default() -> Self {
-        GoSliceData {
-            ptr: null(),
+/// The data we're pointing to is owned by Go and has a lifetime no shorter than the current program.
+unsafe impl Send for GoSliceData {}
+
+impl GoSliceData {
+    pub fn null() -> Self {
+        Self {
+            ptr: ptr::null(),
             len: 0,
         }
     }
-}
 
-impl GoSliceData {
     fn slice(&self) -> &[u8] {
         if self.len == 0 {
             return &[];
@@ -56,32 +60,12 @@ impl GoSliceData {
     }
 }
 
-// same as above, with Send semantics using dirty trickery
-// GO will always use GoSliceData so these types must have
-// exact same representation, see assert_go_slices_match
-#[derive(Clone, Copy, Default)]
-#[repr(C)]
-pub struct SendGoSliceData {
-    ptr: usize, // not stored as pointer because rust won't let that be Send
-    len: usize,
-}
-
-#[allow(dead_code)]
-const fn assert_go_slices_match() {
-    // TODO: this will be stabilized on rust 1.77
-    // assert_eq!(mem::offset_of!(GoSliceData, ptr), mem::offset_of!(SendGoSliceData, ptr));
-    // assert_eq!(mem::offset_of!(GoSliceData, len), mem::offset_of!(SendGoSliceData, len));
-    assert!(mem::size_of::<GoSliceData>() == mem::size_of::<SendGoSliceData>());
-}
-
-const _: () = assert_go_slices_match();
-
-impl DataReader for SendGoSliceData {
+impl DataReader for GoSliceData {
     fn slice(&self) -> &[u8] {
         if self.len == 0 {
             return &[];
         }
-        unsafe { std::slice::from_raw_parts(self.ptr as *const u8, self.len) }
+        unsafe { std::slice::from_raw_parts(self.ptr, self.len) }
     }
 }
 
@@ -110,16 +94,6 @@ pub struct RustBytes {
 }
 
 impl RustBytes {
-    fn new(vec: Vec<u8>) -> Self {
-        let mut rust_vec = Self {
-            ptr: std::ptr::null_mut(),
-            len: 0,
-            cap: 0,
-        };
-        unsafe { rust_vec.write(vec) };
-        rust_vec
-    }
-
     unsafe fn into_vec(self) -> Vec<u8> {
         Vec::from_raw_parts(self.ptr, self.len, self.cap)
     }
@@ -241,17 +215,3 @@ pub unsafe extern "C" fn stylus_drop_vec(vec: RustBytes) {
         mem::drop(vec.into_vec())
     }
 }
-
-/// Overwrites the bytes of the vector.
-///
-/// # Safety
-///
-/// `rust` must not be null.
-#[no_mangle]
-pub unsafe extern "C" fn stylus_vec_set_bytes(rust: *mut RustBytes, data: GoSliceData) {
-    let rust = &mut *rust;
-    let mut vec = Vec::from_raw_parts(rust.ptr, rust.len, rust.cap);
-    vec.clear();
-    vec.extend(data.slice());
-    rust.write(vec);
-}