diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..1e883e8
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "6fc9a706a9312ee801c7e77ca06c0782fa9eadef"
+  }
+}
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..84c47ed
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/target
+**/*.rs.bk
+/Cargo.lock
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..089a54a
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,12 @@
+// This file is generated by cargo2android.py.
+
+rust_library_host_rlib {
+    name: "librustc_hash",
+    crate_name: "rustc_hash",
+    srcs: ["src/lib.rs"],
+    edition: "2015",
+    features: [
+        "default",
+        "std",
+    ],
+}
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..d70b2b5
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,40 @@
+# The Rust Code of Conduct
+
+A version of this document [can be found online](https://www.rust-lang.org/conduct.html).
+
+## Conduct
+
+**Contact**: [rust-mods@rust-lang.org](mailto:rust-mods@rust-lang.org)
+
+* We are committed to providing a friendly, safe and welcoming environment for all, regardless of level of experience, gender identity and expression, sexual orientation, disability, personal appearance, body size, race, ethnicity, age, religion, nationality, or other similar characteristic.
+* On IRC, please avoid using overtly sexual nicknames or other nicknames that might detract from a friendly, safe and welcoming environment for all.
+* Please be kind and courteous. There's no need to be mean or rude.
+* Respect that people have differences of opinion and that every design or implementation choice carries a trade-off and numerous costs. There is seldom a right answer.
+* Please keep unstructured critique to a minimum. If you have solid ideas you want to experiment with, make a fork and see how it works.
+* We will exclude you from interaction if you insult, demean or harass anyone. That is not welcome behavior. We interpret the term "harassment" as including the definition in the <a href="http://citizencodeofconduct.org/">Citizen Code of Conduct</a>; if you have any lack of clarity about what might be included in that concept, please read their definition. In particular, we don't tolerate behavior that excludes people in socially marginalized groups.
+* Private harassment is also unacceptable. No matter who you are, if you feel you have been or are being harassed or made uncomfortable by a community member, please contact one of the channel ops or any of the [Rust moderation team][mod_team] immediately. Whether you're a regular contributor or a newcomer, we care about making this community a safe place for you and we've got your back.
+* Likewise any spamming, trolling, flaming, baiting or other attention-stealing behavior is not welcome.
+
+## Moderation
+
+
+These are the policies for upholding our community's standards of conduct. If you feel that a thread needs moderation, please contact the [Rust moderation team][mod_team].
+
+1. Remarks that violate the Rust standards of conduct, including hateful, hurtful, oppressive, or exclusionary remarks, are not allowed. (Cursing is allowed, but never targeting another user, and never in a hateful manner.)
+2. Remarks that moderators find inappropriate, whether listed in the code of conduct or not, are also not allowed.
+3. Moderators will first respond to such remarks with a warning.
+4. If the warning is unheeded, the user will be "kicked," i.e., kicked out of the communication channel to cool off.
+5. If the user comes back and continues to make trouble, they will be banned, i.e., indefinitely excluded.
+6. Moderators may choose at their discretion to un-ban the user if it was a first offense and they offer the offended party a genuine apology.
+7. If a moderator bans someone and you think it was unjustified, please take it up with that moderator, or with a different moderator, **in private**. Complaints about bans in-channel are not allowed.
+8. Moderators are held to a higher standard than other community members. If a moderator creates an inappropriate situation, they should expect less leeway than others.
+
+In the Rust community we strive to go the extra step to look out for each other. Don't just aim to be technically unimpeachable, try to be your best self. In particular, avoid flirting with offensive or sensitive issues, particularly if they're off-topic; this all too often leads to unnecessary fights, hurt feelings, and damaged trust; worse, it can drive people away from the community entirely.
+
+And if someone takes issue with something you said or did, resist the urge to be defensive. Just stop doing what it was they complained about and apologize. Even if you feel you were misinterpreted or unfairly accused, chances are good there was something you could've communicated better — remember that it's your responsibility to make your fellow Rustaceans comfortable. Everyone wants to get along and we are all here first and foremost because we want to talk about cool technology. You will find that people will be eager to assume good intent and forgive as long as you earn their trust.
+
+The enforcement policies listed above apply to all official Rust venues; including official IRC channels (#rust, #rust-internals, #rust-tools, #rust-libs, #rustc, #rust-beginners, #rust-docs, #rust-community, #rust-lang, and #cargo); GitHub repositories under rust-lang, rust-lang-nursery, and rust-lang-deprecated; and all forums under rust-lang.org (users.rust-lang.org, internals.rust-lang.org). For other projects adopting the Rust Code of Conduct, please contact the maintainers of those projects for enforcement. If you wish to use this code of conduct for your own project, consider explicitly mentioning your moderation policy or making a copy with your own moderation policy so as to avoid confusion.
+
+*Adapted from the [Node.js Policy on Trolling](http://blog.izs.me/post/30036893703/policy-on-trolling) as well as the [Contributor Covenant v1.3.0](https://www.contributor-covenant.org/version/1/3/0/).*
+
+[mod_team]: https://www.rust-lang.org/team.html#Moderation-team
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..47330b7
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,25 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+name = "rustc-hash"
+version = "1.1.0"
+authors = ["The Rust Project Developers"]
+description = "speed, non-cryptographic hash used in rustc"
+readme = "README.md"
+keywords = ["hash", "fxhash", "rustc"]
+license = "Apache-2.0/MIT"
+repository = "https://github.com/rust-lang-nursery/rustc-hash"
+
+[features]
+default = ["std"]
+std = []
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..a28fdb9
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,13 @@
+[package]
+name = "rustc-hash"
+version = "1.1.0"
+authors = ["The Rust Project Developers"]
+description = "speed, non-cryptographic hash used in rustc"
+license = "Apache-2.0/MIT"
+readme = "README.md"
+keywords = ["hash", "fxhash", "rustc"]
+repository = "https://github.com/rust-lang-nursery/rustc-hash"
+
+[features]
+std = []
+default = ["std"]
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..16fe87b
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
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+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
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+   the terms of any separate license agreement you may have executed
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+6. Trademarks. This License does not grant permission to use the trade
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+   Contributor provides its Contributions) on an "AS IS" BASIS,
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+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
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+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
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+   To apply the Apache License to your work, attach the following
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+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
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+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..31aa793
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..249398e
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,19 @@
+name: "rustc-hash"
+description: "A speedy hash algorithm used within rustc. The hashmap in liballoc by default uses SipHash which isn\'t quite as speedy as we want. In the compiler we\'re not really worried about DOS attempts, so we use a fast non-cryptographic hash."
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/rustc-hash"
+  }
+  url {
+    type: GIT
+    value: "https://github.com/rust-lang-nursery/rustc-hash"
+  }
+  version: "1.1.0"
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2020
+    month: 3
+    day: 31
+  }
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..46fc303
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+include platform/prebuilts/rust:/OWNERS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e33057a
--- /dev/null
+++ b/README.md
@@ -0,0 +1,38 @@
+# rustc-hash
+
+[![crates.io](https://img.shields.io/crates/v/rustc-hash.svg)](https://crates.io/crates/rustc-hash)
+[![Documentation](https://docs.rs/rustc-hash/badge.svg)](https://docs.rs/rustc-hash)
+
+A speedy hash algorithm used within rustc. The hashmap in liballoc by
+default uses SipHash which isn't quite as speedy as we want. In the
+compiler we're not really worried about DOS attempts, so we use a fast
+non-cryptographic hash.
+
+This is the same as the algorithm used by Firefox -- which is a
+homespun one not based on any widely-known algorithm -- though
+modified to produce 64-bit hash values instead of 32-bit hash
+values. It consistently out-performs an FNV-based hash within rustc
+itself -- the collision rate is similar or slightly worse than FNV,
+but the speed of the hash function itself is much higher because it
+works on up to 8 bytes at a time.
+
+## Usage
+
+```rust
+use rustc_hash::FxHashMap;
+
+let mut map: FxHashMap<u32, u32> = FxHashMap::default();
+map.insert(22, 44);
+```
+
+### `no_std`
+
+This crate can be used as a `no_std` crate by disabling the `std`
+feature, which is on by default, as follows:
+
+```toml
+rustc-hash = { version = "1.0", default-features = false }
+```
+
+In this configuration, `FxHasher` is the only export, and the
+`FxHashMap`/`FxHashSet` type aliases are omitted.
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..ee9ad31
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,148 @@
+// Copyright 2015 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.
+
+//! Fast, non-cryptographic hash used by rustc and Firefox.
+//!
+//! # Example
+//!
+//! ```rust
+//! # #[cfg(feature = "std")]
+//! # fn main() {
+//! use rustc_hash::FxHashMap;
+//! let mut map: FxHashMap<u32, u32> = FxHashMap::default();
+//! map.insert(22, 44);
+//! # }
+//! # #[cfg(not(feature = "std"))]
+//! # fn main() { }
+//! ```
+
+#![no_std]
+
+#[cfg(feature = "std")]
+extern crate std;
+
+use core::convert::TryInto;
+use core::default::Default;
+#[cfg(feature = "std")]
+use core::hash::BuildHasherDefault;
+use core::hash::Hasher;
+use core::mem::size_of;
+use core::ops::BitXor;
+#[cfg(feature = "std")]
+use std::collections::{HashMap, HashSet};
+
+/// Type alias for a hashmap using the `fx` hash algorithm.
+#[cfg(feature = "std")]
+pub type FxHashMap<K, V> = HashMap<K, V, BuildHasherDefault<FxHasher>>;
+
+/// Type alias for a hashmap using the `fx` hash algorithm.
+#[cfg(feature = "std")]
+pub type FxHashSet<V> = HashSet<V, BuildHasherDefault<FxHasher>>;
+
+/// A speedy hash algorithm for use within rustc. The hashmap in liballoc
+/// by default uses SipHash which isn't quite as speedy as we want. In the
+/// compiler we're not really worried about DOS attempts, so we use a fast
+/// non-cryptographic hash.
+///
+/// This is the same as the algorithm used by Firefox -- which is a homespun
+/// one not based on any widely-known algorithm -- though modified to produce
+/// 64-bit hash values instead of 32-bit hash values. It consistently
+/// out-performs an FNV-based hash within rustc itself -- the collision rate is
+/// similar or slightly worse than FNV, but the speed of the hash function
+/// itself is much higher because it works on up to 8 bytes at a time.
+pub struct FxHasher {
+    hash: usize,
+}
+
+#[cfg(target_pointer_width = "32")]
+const K: usize = 0x9e3779b9;
+#[cfg(target_pointer_width = "64")]
+const K: usize = 0x517cc1b727220a95;
+
+impl Default for FxHasher {
+    #[inline]
+    fn default() -> FxHasher {
+        FxHasher { hash: 0 }
+    }
+}
+
+impl FxHasher {
+    #[inline]
+    fn add_to_hash(&mut self, i: usize) {
+        self.hash = self.hash.rotate_left(5).bitxor(i).wrapping_mul(K);
+    }
+}
+
+impl Hasher for FxHasher {
+    #[inline]
+    fn write(&mut self, mut bytes: &[u8]) {
+        #[cfg(target_pointer_width = "32")]
+        let read_usize = |bytes: &[u8]| u32::from_ne_bytes(bytes[..4].try_into().unwrap());
+        #[cfg(target_pointer_width = "64")]
+        let read_usize = |bytes: &[u8]| u64::from_ne_bytes(bytes[..8].try_into().unwrap());
+
+        let mut hash = FxHasher { hash: self.hash };
+        assert!(size_of::<usize>() <= 8);
+        while bytes.len() >= size_of::<usize>() {
+            hash.add_to_hash(read_usize(bytes) as usize);
+            bytes = &bytes[size_of::<usize>()..];
+        }
+        if (size_of::<usize>() > 4) && (bytes.len() >= 4) {
+            hash.add_to_hash(u32::from_ne_bytes(bytes[..4].try_into().unwrap()) as usize);
+            bytes = &bytes[4..];
+        }
+        if (size_of::<usize>() > 2) && bytes.len() >= 2 {
+            hash.add_to_hash(u16::from_ne_bytes(bytes[..2].try_into().unwrap()) as usize);
+            bytes = &bytes[2..];
+        }
+        if (size_of::<usize>() > 1) && bytes.len() >= 1 {
+            hash.add_to_hash(bytes[0] as usize);
+        }
+        self.hash = hash.hash;
+    }
+
+    #[inline]
+    fn write_u8(&mut self, i: u8) {
+        self.add_to_hash(i as usize);
+    }
+
+    #[inline]
+    fn write_u16(&mut self, i: u16) {
+        self.add_to_hash(i as usize);
+    }
+
+    #[inline]
+    fn write_u32(&mut self, i: u32) {
+        self.add_to_hash(i as usize);
+    }
+
+    #[cfg(target_pointer_width = "32")]
+    #[inline]
+    fn write_u64(&mut self, i: u64) {
+        self.add_to_hash(i as usize);
+        self.add_to_hash((i >> 32) as usize);
+    }
+
+    #[cfg(target_pointer_width = "64")]
+    #[inline]
+    fn write_u64(&mut self, i: u64) {
+        self.add_to_hash(i as usize);
+    }
+
+    #[inline]
+    fn write_usize(&mut self, i: usize) {
+        self.add_to_hash(i);
+    }
+
+    #[inline]
+    fn finish(&self) -> u64 {
+        self.hash as u64
+    }
+}