From 9b2e4a587b498c597b3f9e7f6660b9bae96cc074 Mon Sep 17 00:00:00 2001
From: Blaine Bublitz <blaine.bublitz@gmail.com>
Date: Thu, 18 May 2023 11:30:44 -0700
Subject: [PATCH] feat!: Replace `js` feature with wasm32 target

---
 Cargo.toml | 40 ++++++++++++++++++++++++----------------
 src/lib.rs | 28 ++++++++++++++++------------
 2 files changed, 40 insertions(+), 28 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 46abab51..fa46929f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,9 @@ license = "MIT OR Apache-2.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[lib]
+crate-type = ["cdylib"]
+
 [dependencies]
 acvm = { version = "0.12.0", features = ["bn254"] }
 bincode = "1.3.3"
@@ -18,22 +21,38 @@ serde = { version = "1.0.136", features = ["derive"] }
 serde-big-array = "0.5.1"
 thiserror = "1.0.21"
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 # Native
 barretenberg-sys = { version = "0.1.2", optional = true }
 
 # Wasm
-wasmer = { version = "2.3", optional = true, default-features = false }
+getrandom = { version = "0.2", optional = true }
 rust-embed = { version = "6.6.0", optional = true, features = [
     "debug-embed",
     "interpolate-folder-path",
     "include-exclude",
 ] }
-getrandom = { version = "0.2", optional = true }
+wasmer = { version = "2.3", optional = true, default-features = false, features = [
+    "sys-default",
+    "cranelift",
+    "default-compiler",
+    "default-cranelift",
+    "default-universal"
+] }
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+getrandom = { version = "0.2", features = [ "js" ] }
+rust-embed = { version = "6.6.0", features = [
+    "debug-embed",
+    "interpolate-folder-path",
+    "include-exclude",
+] }
+wasmer = { version = "2.3", default-features = false, features = [ "js-default" ] }
 
 [build-dependencies]
 pkg-config = "0.3"
 
-[dev-dependencies]
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
 tokio = { version = "1.0", features = [ "macros" ] }
 
 [features]
@@ -42,20 +61,9 @@ native = [
     "dep:barretenberg-sys"
 ]
 wasm = [
-    "wasmer",
-    "dep:rust-embed",
-    "dep:getrandom",
-    "wasmer/sys-default",
-    "wasmer/cranelift",
-    "wasmer/default-compiler",
-    "wasmer/default-cranelift",
-    "wasmer/default-universal"
-]
-js = [
-    "wasmer",
+    "dep:wasmer",
     "dep:rust-embed",
-    "dep:getrandom",
-    "wasmer/js-default"
+    "dep:getrandom"
 ]
 
 [patch.crates-io]
diff --git a/src/lib.rs b/src/lib.rs
index 8573c879..cbedb4d2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,14 +4,18 @@
 // `acvm-backend-barretenberg` can either interact with the Barretenberg backend through a static library
 // or through an embedded wasm binary. It does not make sense to include both of these backends at the same time.
 // We then throw a compilation error if both flags are set.
-// TODO: handle JS target.
 #[cfg(all(feature = "native", feature = "wasm"))]
 compile_error!("feature \"native\" and feature \"wasm\" cannot be enabled at the same time");
 
+#[cfg(all(feature = "native", target_arch = "wasm32"))]
+compile_error!("feature \"native\" cannot be enabled for a \"wasm32\" target");
+
+#[cfg(all(feature = "wasm", target_arch = "wasm32"))]
+compile_error!("feature \"wasm\" cannot be enabled for a \"wasm32\" target");
+
 mod acvm_interop;
 mod barretenberg_structures;
 mod composer;
-#[cfg(any(feature = "native", feature = "wasm"))]
 mod crs;
 mod pedersen;
 mod pippenger;
@@ -120,9 +124,9 @@ const FIELD_BYTES: usize = 32;
 
 #[derive(Debug)]
 pub struct Barretenberg {
-    #[cfg(feature = "wasm")]
+    #[cfg(not(feature = "native"))]
     memory: wasmer::Memory,
-    #[cfg(feature = "wasm")]
+    #[cfg(not(feature = "native"))]
     instance: wasmer::Instance,
 }
 
@@ -276,7 +280,7 @@ mod wasm {
         pub(super) fn transfer_to_heap(&self, arr: &[u8], offset: usize) {
             let memory = &self.memory;
 
-            #[cfg(feature = "js")]
+            #[cfg(target_arch = "wasm32")]
             {
                 let view = memory.uint8view();
                 for (byte_id, cell_id) in (offset..(offset + arr.len())).enumerate() {
@@ -284,7 +288,7 @@ mod wasm {
                 }
             }
 
-            #[cfg(not(feature = "js"))]
+            #[cfg(not(target_arch = "wasm32"))]
             {
                 for (byte_id, cell) in memory.uint8view()[offset..(offset + arr.len())]
                     .iter()
@@ -306,13 +310,13 @@ mod wasm {
             let memory = &self.memory;
             let end = start + length;
 
-            #[cfg(feature = "js")]
+            #[cfg(target_arch = "wasm32")]
             return memory
                 .uint8view()
                 .subarray(start as u32, end as u32)
                 .to_vec();
 
-            #[cfg(not(feature = "js"))]
+            #[cfg(not(target_arch = "wasm32"))]
             return memory.view()[start..end]
                 .iter()
                 .map(|cell| cell.get())
@@ -431,7 +435,7 @@ mod wasm {
         let mut ptr_end = 0;
         let byte_view = env.memory.uint8view();
 
-        #[cfg(feature = "js")]
+        #[cfg(target_arch = "wasm32")]
         for (i, cell) in byte_view.to_vec()[ptr as usize..].iter().enumerate() {
             if cell != &0_u8 {
                 ptr_end = i;
@@ -440,7 +444,7 @@ mod wasm {
             }
         }
 
-        #[cfg(not(feature = "js"))]
+        #[cfg(not(target_arch = "wasm32"))]
         for (i, cell) in byte_view[ptr as usize..].iter().enumerate() {
             if cell.get() != 0 {
                 ptr_end = i;
@@ -449,11 +453,11 @@ mod wasm {
             }
         }
 
-        #[cfg(feature = "js")]
+        #[cfg(target_arch = "wasm32")]
         let str_vec: Vec<_> =
             byte_view.to_vec()[ptr as usize..=(ptr + ptr_end as i32) as usize].to_vec();
 
-        #[cfg(not(feature = "js"))]
+        #[cfg(not(target_arch = "wasm32"))]
         let str_vec: Vec<_> = byte_view[ptr as usize..=(ptr + ptr_end as i32) as usize]
             .iter()
             .cloned()