std: Add a new wasm32-unknown-unknown target

.gitmodules

@@ -42,3 +42,9 @@
 [submodule "src/tools/miri"]
 	path = src/tools/miri
 	url = https://github.com/solson/miri.git
+[submodule "src/dlmalloc"]
+	path = src/dlmalloc
+	url = https://github.com/alexcrichton/dlmalloc-rs.git
+[submodule "src/binaryen"]
+	path = src/binaryen
+	url = https://github.com/alexcrichton/binaryen.git

src/bootstrap/check.rs

@@ -1211,7 +1211,8 @@ impl Step for Crate {
                     // ends up messing with various mtime calculations and such.
                     if !name.contains("jemalloc") &&
                        *name != *"build_helper" &&
-                       !(name.starts_with("rustc_") && name.ends_with("san")) {
+                       !(name.starts_with("rustc_") && name.ends_with("san")) &&
+                       name != "dlmalloc" {
                         cargo.arg("-p").arg(&format!("{}:0.0.0", name));
                     }
                     for dep in build.crates[&name].deps.iter() {

src/bootstrap/dist.rs

@@ -672,6 +672,9 @@ fn copy_src_dirs(build: &Build, src_dirs: &[&str], exclude_dirs: &[&str], dst_di
              spath.ends_with(".s")) {
             return false
         }
+        if spath.contains("test/emscripten") || spath.contains("test\\emscripten") {
+            return false
+        }
 
         let full_path = Path::new(dir).join(path);
         if exclude_dirs.iter().any(|excl| full_path == Path::new(excl)) {
@@ -736,6 +739,7 @@ impl Step for Src {
         // (essentially libstd and all of its path dependencies)
         let std_src_dirs = [
             "src/build_helper",
+            "src/dlmalloc",
             "src/liballoc",
             "src/liballoc_jemalloc",
             "src/liballoc_system",
@@ -754,6 +758,7 @@ impl Step for Src {
             "src/libunwind",
             "src/rustc/compiler_builtins_shim",
             "src/rustc/libc_shim",
+            "src/rustc/dlmalloc_shim",
             "src/libtest",
             "src/libterm",
             "src/jemalloc",

src/etc/wasm32-shim.js

@@ -0,0 +1,119 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// This is a small "shim" program which is used when wasm32 unit tests are run
+// in this repository. This program is intended to be run in node.js and will
+// load a wasm module into memory, instantiate it with a set of imports, and
+// then run it.
+//
+// There's a bunch of helper functions defined here in `imports.env`, but note
+// that most of them aren't actually needed to execute most programs. Many of
+// these are just intended for completeness or debugging. Hopefully over time
+// nothing here is needed for completeness.
+
+const fs = require('fs');
+const process = require('process');
+const buffer = fs.readFileSync(process.argv[2]);
+
+Error.stackTraceLimit = 20;
+
+let m = new WebAssembly.Module(buffer);
+
+let memory = null;
+
+function copystr(a, b) {
+  if (memory === null) {
+    return null
+  }
+  let view = new Uint8Array(memory.buffer).slice(a, a + b);
+  return String.fromCharCode.apply(null, view);
+}
+
+let imports = {};
+imports.env = {
+  // These are generated by LLVM itself for various intrinsic calls. Hopefully
+  // one day this is not necessary and something will automatically do this.
+  fmod: function(x, y) { return x % y; },
+  exp2: function(x) { return Math.pow(2, x); },
+  exp2f: function(x) { return Math.pow(2, x); },
+  ldexp: function(x, y) { return x * Math.pow(2, y); },
+  ldexpf: function(x, y) { return x * Math.pow(2, y); },
+  log10: function(x) { return Math.log10(x); },
+  log10f: function(x) { return Math.log10(x); },
+
+  // These are called in src/libstd/sys/wasm/stdio.rs and are used when
+  // debugging is enabled.
+  rust_wasm_write_stdout: function(a, b) {
+    let s = copystr(a, b);
+    if (s !== null) {
+      process.stdout.write(s);
+    }
+  },
+  rust_wasm_write_stderr: function(a, b) {
+    let s = copystr(a, b);
+    if (s !== null) {
+      process.stderr.write(s);
+    }
+  },
+
+  // These are called in src/libstd/sys/wasm/args.rs and are used when
+  // debugging is enabled.
+  rust_wasm_args_count: function() {
+    if (memory === null)
+      return 0;
+    return process.argv.length - 2;
+  },
+  rust_wasm_args_arg_size: function(i) {
+    return process.argv[i + 2].length;
+  },
+  rust_wasm_args_arg_fill: function(idx, ptr) {
+    let arg = process.argv[idx + 2];
+    let view = new Uint8Array(memory.buffer);
+    for (var i = 0; i < arg.length; i++) {
+      view[ptr + i] = arg.charCodeAt(i);
+    }
+  },
+
+  // These are called in src/libstd/sys/wasm/os.rs and are used when
+  // debugging is enabled.
+  rust_wasm_getenv_len: function(a, b) {
+    let key = copystr(a, b);
+    if (key === null) {
+      return -1;
+    }
+    if (!(key in process.env)) {
+      return -1;
+    }
+    return process.env[key].length;
+  },
+  rust_wasm_getenv_data: function(a, b, ptr) {
+    let key = copystr(a, b);
+    let value = process.env[key];
+    let view = new Uint8Array(memory.buffer);
+    for (var i = 0; i < value.length; i++) {
+      view[ptr + i] = value.charCodeAt(i);
+    }
+  },
+};
+
+let module_imports = WebAssembly.Module.imports(m);
+
+for (var i = 0; i < module_imports.length; i++) {
+  let imp = module_imports[i];
+  if (imp.module != 'env') {
+    continue
+  }
+  if (imp.name == 'memory' && imp.kind == 'memory') {
+    memory = new WebAssembly.Memory({initial: 20});
+    imports.env.memory = memory;
+  }
+}
+
+let instance = new WebAssembly.Instance(m, imports);

src/liballoc_jemalloc/build.rs

@@ -31,7 +31,7 @@ fn main() {
     let host = env::var("HOST").expect("HOST was not set");
     if target.contains("rumprun") || target.contains("bitrig") || target.contains("openbsd") ||
        target.contains("msvc") || target.contains("emscripten") || target.contains("fuchsia") ||
-       target.contains("redox") {
+       target.contains("redox") || target.contains("wasm32") {
         println!("cargo:rustc-cfg=dummy_jemalloc");
         return;
     }

src/liballoc_system/Cargo.toml

@@ -13,3 +13,7 @@ doc = false
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
 libc = { path = "../rustc/libc_shim" }
+
+# See comments in the source for what this dependency is
+[target.'cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))'.dependencies]
+dlmalloc = { path = "../rustc/dlmalloc_shim" }

src/liballoc_system/lib.rs

@@ -34,12 +34,14 @@
               target_arch = "powerpc64",
               target_arch = "asmjs",
               target_arch = "wasm32")))]
+#[allow(dead_code)]
 const MIN_ALIGN: usize = 8;
 #[cfg(all(any(target_arch = "x86_64",
               target_arch = "aarch64",
               target_arch = "mips64",
               target_arch = "s390x",
               target_arch = "sparc64")))]
+#[allow(dead_code)]
 const MIN_ALIGN: usize = 16;
 
 extern crate alloc;
@@ -458,3 +460,91 @@ mod platform {
         }
     }
 }
+
+// This is an implementation of a global allocator on the wasm32 platform when
+// emscripten is not in use. In that situation there's no actual runtime for us
+// to lean on for allocation, so instead we provide our own!
+//
+// The wasm32 instruction set has two instructions for getting the current
+// amount of memory and growing the amount of memory. These instructions are the
+// foundation on which we're able to build an allocator, so we do so! Note that
+// the instructions are also pretty "global" and this is the "global" allocator
+// after all!
+//
+// The current allocator here is the `dlmalloc` crate which we've got included
+// in the rust-lang/rust repository as a submodule. The crate is a port of
+// dlmalloc.c from C to Rust and is basically just so we can have "pure Rust"
+// for now which is currently technically required (can't link with C yet).
+//
+// The crate itself provides a global allocator which on wasm has no
+// synchronization as there are no threads!
+#[cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))]
+mod platform {
+    extern crate dlmalloc;
+
+    use alloc::heap::{Alloc, AllocErr, Layout, Excess, CannotReallocInPlace};
+    use System;
+    use self::dlmalloc::GlobalDlmalloc;
+
+    #[unstable(feature = "allocator_api", issue = "32838")]
+    unsafe impl<'a> Alloc for &'a System {
+        #[inline]
+        unsafe fn alloc(&mut self, layout: Layout) -> Result<*mut u8, AllocErr> {
+            GlobalDlmalloc.alloc(layout)
+        }
+
+        #[inline]
+        unsafe fn alloc_zeroed(&mut self, layout: Layout)
+            -> Result<*mut u8, AllocErr>
+        {
+            GlobalDlmalloc.alloc_zeroed(layout)
+        }
+
+        #[inline]
+        unsafe fn dealloc(&mut self, ptr: *mut u8, layout: Layout) {
+            GlobalDlmalloc.dealloc(ptr, layout)
+        }
+
+        #[inline]
+        unsafe fn realloc(&mut self,
+                          ptr: *mut u8,
+                          old_layout: Layout,
+                          new_layout: Layout) -> Result<*mut u8, AllocErr> {
+            GlobalDlmalloc.realloc(ptr, old_layout, new_layout)
+        }
+
+        #[inline]
+        fn usable_size(&self, layout: &Layout) -> (usize, usize) {
+            GlobalDlmalloc.usable_size(layout)
+        }
+
+        #[inline]
+        unsafe fn alloc_excess(&mut self, layout: Layout) -> Result<Excess, AllocErr> {
+            GlobalDlmalloc.alloc_excess(layout)
+        }
+
+        #[inline]
+        unsafe fn realloc_excess(&mut self,
+                                 ptr: *mut u8,
+                                 layout: Layout,
+                                 new_layout: Layout) -> Result<Excess, AllocErr> {
+            GlobalDlmalloc.realloc_excess(ptr, layout, new_layout)
+        }
+
+        #[inline]
+        unsafe fn grow_in_place(&mut self,
+                                ptr: *mut u8,
+                                layout: Layout,
+                                new_layout: Layout) -> Result<(), CannotReallocInPlace> {
+            GlobalDlmalloc.grow_in_place(ptr, layout, new_layout)
+        }
+
+        #[inline]
+        unsafe fn shrink_in_place(&mut self,
+                                  ptr: *mut u8,
+                                  layout: Layout,
+                                  new_layout: Layout) -> Result<(), CannotReallocInPlace> {
+            GlobalDlmalloc.shrink_in_place(ptr, layout, new_layout)
+        }
+    }
+}

src/libcore/Cargo.toml

@@ -9,9 +9,6 @@ path = "lib.rs"
 test = false
 bench = false
 
-[dev-dependencies]
-rand = "0.3"
-
 [[test]]
 name = "coretests"
 path = "../libcore/tests/lib.rs"

src/libcore/tests/lib.rs

@@ -27,7 +27,6 @@
 #![feature(iter_rfind)]
 #![feature(iter_rfold)]
 #![feature(nonzero)]
-#![feature(rand)]
 #![feature(raw)]
 #![feature(refcell_replace_swap)]
 #![feature(sip_hash_13)]
@@ -48,7 +47,6 @@
 
 extern crate core;
 extern crate test;
-extern crate rand;
 
 mod any;
 mod array;