Promote the wasm32-wasip2 target to Tier 2

alexcrichton · alexcrichton · commit 2a3e22bf04b4 · 2024-07-09T12:11:08.000-07:00
This commit promotes the `wasm32-wasip2` Rust target to tier 2 as proposed in rust-lang/compiler-team#760. There are two major changes in this PR: 1. The `dist-various-2` container, which already produces the other WASI targets, now has an extra target added for `wasm32-wasip2`. 2. A new `wasm-component-ld` binary is added to all host toolchains when LLD is enabled. This is the linker used for the `wasm32-wasip2` target. This new linker is added for all host toolchains to ensure that all host toolchains can produce the `wasm32-wasip2` target. This is similar to how `rust-lld` was originally included for all host toolchains to be able to produce WebAssembly output when the targets were first added. The new linker is developed [here][wasm-component-ld] and is pulled in via a crates.io-based dependency to the tree here. [wasm-component-ld]: https://github.com/bytecodealliance/wasm-component-ld
diff --git a/Cargo.lock b/Cargo.lock
@@ -1671,6 +1671,7 @@ dependencies = [
  "compiler_builtins",
  "rustc-std-workspace-alloc",
  "rustc-std-workspace-core",
+ "serde",
 ]
 
 [[package]]
@@ -1880,6 +1881,12 @@ dependencies = [
  "syn 2.0.67",
 ]
 
+[[package]]
+name = "id-arena"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25a2bc672d1148e28034f176e01fffebb08b35768468cc954630da77a1449005"
+
 [[package]]
 name = "ident_case"
 version = "1.0.1"
@@ -2109,6 +2116,12 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "db13adb97ab515a3691f56e4dbab09283d0b86cb45abd991d8634a9d6f501760"
 
+[[package]]
+name = "lexopt"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baff4b617f7df3d896f97fe922b64817f6cd9a756bb81d40f8883f2f66dcb401"
+
 [[package]]
 name = "libc"
 version = "0.2.155"
@@ -2623,7 +2636,7 @@ dependencies = [
  "indexmap",
  "memchr",
  "ruzstd 0.5.0",
- "wasmparser",
+ "wasmparser 0.118.2",
 ]
 
 [[package]]
@@ -3424,7 +3437,7 @@ dependencies = [
  "object 0.34.0",
  "regex",
  "similar",
- "wasmparser",
+ "wasmparser 0.118.2",
 ]
 
 [[package]]
@@ -3805,7 +3818,7 @@ dependencies = [
  "thin-vec",
  "thorin-dwp",
  "tracing",
- "wasm-encoder",
+ "wasm-encoder 0.200.0",
  "windows",
 ]
 
@@ -5248,6 +5261,15 @@ dependencies = [
  "color-eyre",
 ]
 
+[[package]]
+name = "spdx"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47317bbaf63785b53861e1ae2d11b80d6b624211d42cb20efcd210ee6f8a14bc"
+dependencies = [
+ "smallvec",
+]
+
 [[package]]
 name = "spdx-expression"
 version = "0.5.2"
@@ -6296,6 +6318,28 @@ version = "0.2.92"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "af190c94f2773fdb3729c55b007a722abb5384da03bc0986df4c289bf5567e96"
 
+[[package]]
+name = "wasm-component-ld"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "314d932d5e84c9678751b85498b1482b2f32f185744e449d3ce0b1d400376dad"
+dependencies = [
+ "anyhow",
+ "clap",
+ "lexopt",
+ "tempfile",
+ "wasmparser 0.210.0",
+ "wat",
+ "wit-component",
+]
+
+[[package]]
+name = "wasm-component-ld-wrapper"
+version = "0.1.0"
+dependencies = [
+ "wasm-component-ld",
+]
+
 [[package]]
 name = "wasm-encoder"
 version = "0.200.0"
@@ -6305,6 +6349,40 @@ dependencies = [
  "leb128",
 ]
 
+[[package]]
+name = "wasm-encoder"
+version = "0.210.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e7e3764d9d6edabd8c9e16195e177be0d20f6ab942ad18af52860f12f82bc59a"
+dependencies = [
+ "leb128",
+]
+
+[[package]]
+name = "wasm-encoder"
+version = "0.211.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e7d931a1120ef357f32b74547646b6fa68ea25e377772b72874b131a9ed70d4"
+dependencies = [
+ "leb128",
+]
+
+[[package]]
+name = "wasm-metadata"
+version = "0.210.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "012729d1294907fcb0866f08460ab95426a6d0b176a599619b84cac7653452b4"
+dependencies = [
+ "anyhow",
+ "indexmap",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "spdx",
+ "wasm-encoder 0.210.0",
+ "wasmparser 0.210.0",
+]
+
 [[package]]
 name = "wasmparser"
 version = "0.118.2"
@@ -6315,6 +6393,42 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "wasmparser"
+version = "0.210.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7bbcd21e7581619d9f6ca00f8c4f08f1cacfe58bf63f83af57cd0476f1026f5"
+dependencies = [
+ "ahash",
+ "bitflags 2.5.0",
+ "hashbrown",
+ "indexmap",
+ "semver",
+ "serde",
+]
+
+[[package]]
+name = "wast"
+version = "211.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b25506dd82d00da6b14a87436b3d52b1d264083fa79cdb72a0d1b04a8595ccaa"
+dependencies = [
+ "bumpalo",
+ "leb128",
+ "memchr",
+ "unicode-width",
+ "wasm-encoder 0.211.1",
+]
+
+[[package]]
+name = "wat"
+version = "1.211.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eb716ca6c86eecac2d82541ffc39860118fc0af9309c4f2670637bea2e1bdd7d"
+dependencies = [
+ "wast",
+]
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -6542,6 +6656,43 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "wit-component"
+version = "0.210.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a450bdb5d032acf1fa0865451fa0c6f50e62f2d31eaa8dba967c2e2d068694a4"
+dependencies = [
+ "anyhow",
+ "bitflags 2.5.0",
+ "indexmap",
+ "log",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "wasm-encoder 0.210.0",
+ "wasm-metadata",
+ "wasmparser 0.210.0",
+ "wit-parser",
+]
+
+[[package]]
+name = "wit-parser"
+version = "0.210.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60a965cbd439af19a4b44a54a97ab8957d86f02d01320efc9e31c1d3605c6710"
+dependencies = [
+ "anyhow",
+ "id-arena",
+ "indexmap",
+ "log",
+ "semver",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "unicode-xid",
+ "wasmparser 0.210.0",
+]
+
 [[package]]
 name = "writeable"
 version = "0.5.5"
diff --git a/Cargo.toml b/Cargo.toml
@@ -45,6 +45,7 @@ members = [
   "src/tools/opt-dist",
   "src/tools/coverage-dump",
   "src/tools/rustc-perf-wrapper",
+  "src/tools/wasm-component-ld",
 ]
 
 exclude = [
@@ -104,6 +105,9 @@ rustc-demangle.debug = 0
 [profile.release.package.lld-wrapper]
 debug = 0
 strip = true
+[profile.release.package.wasm-component-ld-wrapper]
+debug = 0
+strip = true
 
 [patch.crates-io]
 # See comments in `library/rustc-std-workspace-core/README.md` for what's going on
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
@@ -1829,6 +1829,21 @@ impl Step for Assemble {
                     &self_contained_lld_dir.join(exe(name, target_compiler.host)),
                 );
             }
+
+            // In addition to `rust-lld` also install `wasm-component-ld` when
+            // LLD is enabled. This is a relatively small binary that primarily
+            // delegates to the `rust-lld` binary for linking and then runs
+            // logic to create the final binary. This is used by the
+            // `wasm32-wasip2` target of Rust.
+            let wasm_component_ld_exe =
+                builder.ensure(crate::core::build_steps::tool::WasmComponentLd {
+                    compiler: build_compiler,
+                    target: target_compiler.host,
+                });
+            builder.copy_link(
+                &wasm_component_ld_exe,
+                &libdir_bin.join(wasm_component_ld_exe.file_name().unwrap()),
+            );
         }
 
         if builder.config.llvm_enabled(target_compiler.host) {
diff --git a/src/bootstrap/src/core/build_steps/tool.rs b/src/bootstrap/src/core/build_steps/tool.rs
@@ -701,6 +701,34 @@ impl Step for LldWrapper {
     }
 }
 
+#[derive(Debug, Clone, Hash, PartialEq, Eq)]
+pub struct WasmComponentLd {
+    pub compiler: Compiler,
+    pub target: TargetSelection,
+}
+
+impl Step for WasmComponentLd {
+    type Output = PathBuf;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        run.never()
+    }
+
+    fn run(self, builder: &Builder<'_>) -> PathBuf {
+        builder.ensure(ToolBuild {
+            compiler: self.compiler,
+            target: self.target,
+            tool: "wasm-component-ld",
+            mode: Mode::ToolStd,
+            path: "src/tools/wasm-component-ld",
+            source_type: SourceType::InTree,
+            extra_features: Vec::new(),
+            allow_features: "",
+            cargo_args: Vec::new(),
+        })
+    }
+}
+
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub struct RustAnalyzer {
     pub compiler: Compiler,
diff --git a/src/ci/docker/host-x86_64/dist-various-2/Dockerfile b/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
@@ -112,6 +112,7 @@ ENV TARGETS=$TARGETS,wasm32-unknown-unknown
 ENV TARGETS=$TARGETS,wasm32-wasi
 ENV TARGETS=$TARGETS,wasm32-wasip1
 ENV TARGETS=$TARGETS,wasm32-wasip1-threads
+ENV TARGETS=$TARGETS,wasm32-wasip2
 ENV TARGETS=$TARGETS,sparcv9-sun-solaris
 ENV TARGETS=$TARGETS,x86_64-pc-solaris
 ENV TARGETS=$TARGETS,x86_64-unknown-linux-gnux32
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
@@ -95,7 +95,12 @@ const EXCEPTIONS: ExceptionList = &[
     ("self_cell", "Apache-2.0"),                             // rustc (fluent translations)
     ("snap", "BSD-3-Clause"),                                // rustc
     ("wasm-encoder", "Apache-2.0 WITH LLVM-exception"),      // rustc
+    ("wasm-metadata", "Apache-2.0 WITH LLVM-exception"),     // rustc
     ("wasmparser", "Apache-2.0 WITH LLVM-exception"),        // rustc
+    ("wast", "Apache-2.0 WITH LLVM-exception"),              // rustc
+    ("wat", "Apache-2.0 WITH LLVM-exception"),               // rustc
+    ("wit-component", "Apache-2.0 WITH LLVM-exception"),     // rustc
+    ("wit-parser", "Apache-2.0 WITH LLVM-exception"),        // rustc
     // tidy-alphabetical-end
 ];
 
diff --git a/src/tools/wasm-component-ld/Cargo.toml b/src/tools/wasm-component-ld/Cargo.toml
@@ -0,0 +1,13 @@
+# See the `README.md` in this directory for what this tool is.
+
+[package]
+name = "wasm-component-ld-wrapper"
+version = "0.1.0"
+edition = "2021"
+
+[[bin]]
+name = "wasm-component-ld"
+path = "src/main.rs"
+
+[dependencies]
+wasm-component-ld = "0.5.4"
diff --git a/src/tools/wasm-component-ld/README.md b/src/tools/wasm-component-ld/README.md
diff --git a/src/tools/wasm-component-ld/src/main.rs b/src/tools/wasm-component-ld/src/main.rs
