Auto merge of rust-lang#127754 - Urgau:blake3-hash, r=<try>

bors · bors · commit bb01f8b8a21f · 2024-07-15T11:22:43.000Z
[perf] Change stable hasher to Blake3 Based on rust-lang/rustc-stable-hash@main...Urgau:rustc-stable-hash:blake3 cc `@michaelwoerister` r? ghost
diff --git a/Cargo.lock b/Cargo.lock
@@ -243,6 +243,12 @@ dependencies = [
  "object 0.32.2",
 ]
 
+[[package]]
+name = "arrayref"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b4930d2cb77ce62f89ee5d5289b4ac049559b1c45539271f5ed4fdc7db34545"
+
 [[package]]
 name = "arrayvec"
 version = "0.7.4"
@@ -362,6 +368,19 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
+[[package]]
+name = "blake3"
+version = "1.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e9ec96fe9a81b5e365f9db71fe00edc4fe4ca2cc7dcb7861f0603012a7caa210"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "cc",
+ "cfg-if",
+ "constant_time_eq",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -848,6 +867,12 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "constant_time_eq"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7144d30dcf0fafbce74250a3963025d8d52177934239851c917d29f1df280c2"
+
 [[package]]
 name = "core"
 version = "0.0.0"
@@ -3518,8 +3543,10 @@ checksum = "5be1bdc7edf596692617627bbfeaba522131b18e06ca4df2b6b689e3c5d5ce84"
 [[package]]
 name = "rustc-stable-hash"
 version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5c9f15eec8235d7cb775ee6f81891db79b98fd54ba1ad8fae565b88ef1ae4e2"
+source = "git+https://github.com/Urgau/rustc-stable-hash.git?rev=368f4ef#368f4ef468ca97fd4757c896f53349d9fa4def1b"
+dependencies = [
+ "blake3",
+]
 
 [[package]]
 name = "rustc-std-workspace-alloc"
diff --git a/compiler/rustc_data_structures/Cargo.toml b/compiler/rustc_data_structures/Cargo.toml
@@ -15,7 +15,7 @@ jobserver_crate = { version = "0.1.28", package = "jobserver" }
 measureme = "11"
 rustc-hash = "1.1.0"
 rustc-rayon = { version = "0.5.0", optional = true }
-rustc-stable-hash = { version = "0.1.0", features = ["nightly"] }
+rustc-stable-hash = { git = "https://github.com/Urgau/rustc-stable-hash.git", rev = "368f4ef", features = ["nightly", "blake3"] }
 rustc_arena = { path = "../rustc_arena" }
 rustc_graphviz = { path = "../rustc_graphviz" }
 rustc_index = { path = "../rustc_index", package = "rustc_index" }
diff --git a/compiler/rustc_data_structures/src/fingerprint.rs b/compiler/rustc_data_structures/src/fingerprint.rs
@@ -158,8 +158,17 @@ impl FromStableHash for Fingerprint {
     type Hash = StableHasherHash;
 
     #[inline]
-    fn from(StableHasherHash([_0, _1]): Self::Hash) -> Self {
-        Fingerprint(_0, _1)
+    fn from(hash: Self::Hash) -> Self {
+        let bytes: &[u8; 32] = hash.as_bytes();
+
+        let p0 = u64::from_le_bytes(bytes[0..8].try_into().unwrap());
+        let p1 = u64::from_le_bytes(bytes[8..16].try_into().unwrap());
+        let p2 = u64::from_le_bytes(bytes[16..24].try_into().unwrap());
+        let p3 = u64::from_le_bytes(bytes[24..32].try_into().unwrap());
+
+        // See https://stackoverflow.com/a/27952689 on why this function is
+        // implemented this way.
+        Fingerprint(p0.wrapping_mul(3).wrapping_add(p1), p2.wrapping_mul(3).wrapping_add(p3))
     }
 }
 
diff --git a/compiler/rustc_data_structures/src/hashes.rs b/compiler/rustc_data_structures/src/hashes.rs
@@ -60,8 +60,21 @@ impl FromStableHash for Hash64 {
     type Hash = StableHasherHash;
 
     #[inline]
-    fn from(StableHasherHash([_0, __1]): Self::Hash) -> Self {
-        Self { inner: _0 }
+    fn from(hash: Self::Hash) -> Self {
+        let bytes = hash.as_bytes();
+
+        let p0 = u64::from_le_bytes(bytes[0..8].try_into().unwrap());
+        let p1 = u64::from_le_bytes(bytes[8..16].try_into().unwrap());
+        let p2 = u64::from_le_bytes(bytes[16..24].try_into().unwrap());
+        let p3 = u64::from_le_bytes(bytes[24..32].try_into().unwrap());
+
+        // See https://stackoverflow.com/a/27952689 on why this function is
+        // implemented this way.
+        let m0 = p0.wrapping_mul(3).wrapping_add(p1);
+        let m1 = p2.wrapping_mul(3).wrapping_add(p3);
+        let h = m0.wrapping_mul(3).wrapping_add(m1);
+
+        Self { inner: h }
     }
 }
 
@@ -127,8 +140,20 @@ impl FromStableHash for Hash128 {
     type Hash = StableHasherHash;
 
     #[inline]
-    fn from(StableHasherHash([_0, _1]): Self::Hash) -> Self {
-        Self { inner: u128::from(_0) | (u128::from(_1) << 64) }
+    fn from(hash: Self::Hash) -> Self {
+        let bytes = hash.as_bytes();
+
+        let p0 = u64::from_le_bytes(bytes[0..8].try_into().unwrap());
+        let p1 = u64::from_le_bytes(bytes[8..16].try_into().unwrap());
+        let p2 = u64::from_le_bytes(bytes[16..24].try_into().unwrap());
+        let p3 = u64::from_le_bytes(bytes[24..32].try_into().unwrap());
+
+        // See https://stackoverflow.com/a/27952689 on why this function is
+        // implemented this way.
+        let upper = p0.wrapping_mul(3).wrapping_add(p1);
+        let lower = p2.wrapping_mul(3).wrapping_add(p3);
+
+        Self { inner: u128::from(lower) | (u128::from(upper) << 64) }
     }
 }
 
diff --git a/compiler/rustc_data_structures/src/stable_hasher.rs b/compiler/rustc_data_structures/src/stable_hasher.rs
@@ -11,9 +11,9 @@ mod tests;
 
 pub use crate::hashes::{Hash128, Hash64};
 
+pub use rustc_stable_hash::hashers::Blake3Hash as StableHasherHash;
+pub use rustc_stable_hash::hashers::StableBlake3Hasher as StableHasher;
 pub use rustc_stable_hash::FromStableHash;
-pub use rustc_stable_hash::SipHasher128Hash as StableHasherHash;
-pub use rustc_stable_hash::StableSipHasher128 as StableHasher;
 
 /// Something that implements `HashStable<CTX>` can be hashed in a way that is
 /// stable across multiple compilation sessions.
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
@@ -21,6 +21,9 @@ const LICENSES: &[&str] = &[
     "Apache-2.0",
     "Apache-2.0/MIT",
     "BSD-2-Clause OR Apache-2.0 OR MIT",                   // zerocopy
+    "BSD-2-Clause",                                        // arrayref
+    "CC0-1.0 OR Apache-2.0 OR Apache-2.0 WITH LLVM-exception", // blake3
+    "CC0-1.0 OR MIT-0 OR Apache-2.0",                      // constant_time_eq
     "ISC",
     "MIT / Apache-2.0",
     "MIT OR Apache-2.0 OR LGPL-2.1-or-later",              // r-efi, r-efi-alloc
@@ -232,15 +235,18 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "annotate-snippets",
     "anstyle",
     "ar_archive_writer",
+    "arrayref",
     "arrayvec",
     "autocfg",
     "bitflags",
+    "blake3",
     "block-buffer",
     "byteorder", // via ruzstd in object in thorin-dwp
     "cc",
     "cfg-if",
     "cfg_aliases",
     "compiler_builtins",
+    "constant_time_eq",
     "cpufeatures",
     "crc32fast",
     "crossbeam-channel",
diff --git a/src/tools/tidy/src/extdeps.rs b/src/tools/tidy/src/extdeps.rs
@@ -9,6 +9,8 @@ const ALLOWED_SOURCES: &[&str] = &[
     r#""registry+https://github.com/rust-lang/crates.io-index""#,
     // This is `rust_team_data` used by `site` in src/tools/rustc-perf,
     r#""git+https://github.com/rust-lang/team#a5260e76d3aa894c64c56e6ddc8545b9a98043ec""#,
+    // WIP blake3
+    r#""git+https://github.com/Urgau/rustc-stable-hash.git?rev=368f4ef#368f4ef468ca97fd4757c896f53349d9fa4def1b""#,
 ];
 
 /// Checks for external package sources. `root` is the path to the directory that contains the
