Use SipHash-1-3 instead of SipHash-2-4 for StableHasher #107925

thomcc · 2023-02-11T15:33:35Z

Noticed this, and it seems easy and likely a perf win. IIUC we don't need DDOS resistance (just collision) so we ideally would have an even faster hash, but it's hard to beat this SipHash impl here, since it's been so highly tuned for the interface.

It wouldn't surprise me if there's some subtle reason changing this sucks, as it's so obvious it seems likely to have been done. Still, SipHash-1-3 seems to still have the guarantees StableHasher should need (and seemingly more), and is clearly less work. So it's worth a shot.

Not fully tested locally.

rustbot · 2023-02-11T15:33:41Z

r? @eholk

(rustbot has picked a reviewer for you, use r? to override)

thomcc · 2023-02-11T15:47:48Z

@bors try @rust-timer queue

bors · 2023-02-11T15:47:57Z

⌛ Trying commit eacb450ac4c9466e963eb83b0369b9f8c03ad767 with merge 4582a54eeee75d64929d904e543e349ee8262268...

thomcc · 2023-02-11T16:01:13Z

(Oof, kicked off perf too soon...)

Nilstrieb · 2023-02-11T19:03:25Z

cc @michaelwoerister @cjgillot

thomcc · 2023-02-12T05:38:40Z

@bors try @rust-timer queue

bors · 2023-02-12T05:38:49Z

⌛ Trying commit 7d93880711f3e2300d32861a4b9fabb98c37fd66 with merge aa405e0569494aa0d8259bc2457fc38b186105c7...

bors · 2023-02-12T08:29:57Z

☀️ Try build successful - checks-actions
Build commit: aa405e0569494aa0d8259bc2457fc38b186105c7 (aa405e0569494aa0d8259bc2457fc38b186105c7)

rust-timer · 2023-02-12T09:48:52Z

Finished benchmarking commit (aa405e0569494aa0d8259bc2457fc38b186105c7): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.9%	[2.9%, 2.9%]	1
Improvements ✅ (primary)	-2.4%	[-4.1%, -0.2%]	177
Improvements ✅ (secondary)	-2.5%	[-25.3%, -0.3%]	160
All ❌✅ (primary)	-2.4%	[-4.1%, -0.2%]	177

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.1%	[1.1%, 1.1%]	1
Regressions ❌ (secondary)	4.1%	[1.7%, 6.6%]	2
Improvements ✅ (primary)	-3.5%	[-3.5%, -3.5%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.2%	[-3.5%, 1.1%]	2

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.2%	[-4.1%, -1.2%]	85
Improvements ✅ (secondary)	-4.4%	[-25.8%, -1.6%]	43
All ❌✅ (primary)	-2.2%	[-4.1%, -1.2%]	85

WaffleLapkin · 2023-02-12T19:37:34Z

There is only a single perf regression (which is likely due to noise) and a lot of perf wins, so I guess
@rustbot label +perf-regression-triaged

cjgillot · 2023-02-12T21:29:27Z

I don't know anything about hashing functions, but I agree that we don't need DDOS resistance.
The perf results are pretty convincing.
@bors r+

bors · 2023-02-12T21:29:28Z

📌 Commit 7d93880711f3e2300d32861a4b9fabb98c37fd66 has been approved by cjgillot

It is now in the queue for this repository.

thomcc · 2023-02-12T22:39:51Z

There are also 0 regressions under the "Cycles" view and similar speedups, which is nice to see (it's noisier but more closely corresponds to what users will experience IIUC).

As for whether or not this causes problems for us due to being weaker, my understanding is that it should not. I'm not a cryptographer, so someone is free to correct me, but I've done enough work on software involving cryptography to be fairly confident about this much. (Still, @tarcieri might want to weigh in to make sure I'm not blundering here)

My understanding is that the the only valuable property we want out of this hash is a low collision rate when used with a fixed key. This is required to avoid soundness issues, miscompilations, ICEs, and other problems. This means that key-recovery attacks and distinguishers (some of which do apply to other SipHash round choices, but not 1-3) do not matter at all here.

According to these papers, this change allows certain attacks¹ to find a collision in the internal state in less time.

Specifically, for SipHash-1-* there are attacks which cause a collision with probability 2^-167, but for SipHash-2-* the best known attack is probability 2^-236. (Note that the internal state is 256 bits, and in SipHash-c-d the c is the number of ARX rounds used when integrating the input with the internal state, and the d is the number of rounds used to produce the final output, so for a collision in the internal state only the first number is relevant).

However, we are using a 128 bits of hash output, so the chance of a collision (due to the birthday problem) is 2^-64, which is true no matter how good of a hash function we use. This means that the change doesn't materially increase collision likelihood — it's still staggeringly unlikely before and after.

This does make me wonder why it wasn't done before, but who knows — that code clearly has been optimized quite a bit already, and this seems like the first thing you'd try.

Also, I suspect we could also reduce the output rounds even more, but I suspect a better hash algorithm is a more useful investigation to do, it just has to be implemented really carefully to be an improvement given the way StableHasher is used (an off-the-shelf implementation is almost certainly not going to be an improvement from something this carefully tuned for it's use case).

These attacks require actively searching for collisions, rather than just achieving them randomly, so they should just be taken as a bound on the probability. search algorithm driven by the output of the hasher as well, so they're bounds on the actual probability — real-world use should have even fewer collisions. ↩

thomcc · 2023-02-12T22:40:43Z

Oh it got r+ while i was writing that, lol.

scottmcm · 2023-02-13T03:01:59Z

I think this is the easiest "If you can justify the regressions found in this try perf run" I've ever seen 😆

michaelwoerister · 2023-02-13T10:22:58Z

This was discussed a few years ago (see #41215). Back then the measured difference between the 1-3 and the 2-4 was very small -- but a lot has changed since then. We just want collision probability to stay roughly the same.

The ids for the multiple `Item` associated type elements are swapped between the first and second impl.

The order in which the multiple errors for the ambiguous intra doc links are printed is different.

The function names with const generic parameters are printed in a different order.

lqd · 2023-04-05T16:27:22Z

@bors r=cjgillot

bors · 2023-04-05T16:27:24Z

📌 Commit 46a3d28 has been approved by cjgillot

It is now in the queue for this repository.

bors · 2023-04-05T18:35:37Z

⌛ Testing commit 46a3d28 with merge 2e486be...

bors · 2023-04-05T20:50:26Z

☀️ Test successful - checks-actions
Approved by: cjgillot
Pushing 2e486be to master...

rust-timer · 2023-04-05T22:08:06Z

Finished benchmarking commit (2e486be): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.3%	[-4.0%, -0.2%]	184
Improvements ✅ (secondary)	-2.6%	[-32.1%, -0.2%]	153
All ❌✅ (primary)	-2.3%	[-4.0%, -0.2%]	184

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.1%	[1.1%, 1.1%]	1
Regressions ❌ (secondary)	1.5%	[1.5%, 1.5%]	1
Improvements ✅ (primary)	-1.5%	[-2.6%, -0.5%]	2
Improvements ✅ (secondary)	-2.1%	[-4.0%, -1.1%]	5
All ❌✅ (primary)	-0.7%	[-2.6%, 1.1%]	3

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-1.8%	[-3.4%, -0.9%]	79
Improvements ✅ (secondary)	-3.7%	[-28.9%, -1.7%]	42
All ❌✅ (primary)	-1.8%	[-3.4%, -0.9%]	79

This seems to significantly improves performance. Inspired by rust-lang/rust#107925

Pkgsrc changes: * Adjust patches and cargo checksums to new versions. * Adjust to not cross-build to 8.0, due to LLVM using c++17, so adjust USE_LANGUAGES. Upstream changes: Version 1.70.0 (2023-06-01) ========================== Language -------- - [Relax ordering rules for `asm!` operands] (rust-lang/rust#105798) - [Properly allow macro expanded `format_args` invocations to uses captures] (rust-lang/rust#106505) - [Lint ambiguous glob re-exports] (rust-lang/rust#107880) - [Perform const and unsafe checking for expressions in `let _ = expr` position.] (rust-lang/rust#102256) Compiler -------- - [Extend -Cdebuginfo with new options and named aliases] (rust-lang/rust#109808) This provides a smaller version of debuginfo for cases that only need line number information (`-Cdebuginfo=line-tables-only`), which may eventually become the default for `-Cdebuginfo=1`. - [Make `unused_allocation` lint against `Box::new` too] (rust-lang/rust#104363) - [Detect uninhabited types early in const eval] (rust-lang/rust#109435) - [Switch to LLD as default linker for {arm,thumb}v4t-none-eabi] (rust-lang/rust#109721) - [Add tier 3 target `loongarch64-unknown-linux-gnu`] (rust-lang/rust#96971) - [Add tier 3 target for `i586-pc-nto-qnx700` (QNX Neutrino RTOS, version 7.0)] (rust-lang/rust#109173), - [Insert alignment checks for pointer dereferences as debug assertions] (rust-lang/rust#98112) This catches undefined behavior at runtime, and may cause existing code to fail. Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [Document NonZeroXxx layout guarantees] (rust-lang/rust#94786) - [Windows: make `Command` prefer non-verbatim paths] (rust-lang/rust#96391) - [Implement Default for some alloc/core iterators] (rust-lang/rust#99929) - [Fix handling of trailing bare CR in str::lines] (rust-lang/rust#100311) - [allow negative numeric literals in `concat!`] (rust-lang/rust#106844) - [Add documentation about the memory layout of `Cell`] (rust-lang/rust#106921) - [Use `partial_cmp` to implement tuple `lt`/`le`/`ge`/`gt`] (rust-lang/rust#108157) - [Stabilize `atomic_as_ptr`] (rust-lang/rust#108419) - [Stabilize `nonnull_slice_from_raw_parts`] (rust-lang/rust#97506) - [Partial stabilization of `once_cell`] (rust-lang/rust#105587) - [Stabilize `nonzero_min_max`] (rust-lang/rust#106633) - [Flatten/inline format_args!() and (string and int) literal arguments into format_args!()] (rust-lang/rust#106824) - [Stabilize movbe target feature] (rust-lang/rust#107711) - [don't splice from files into pipes in io::copy] (rust-lang/rust#108283) - [Add a builtin unstable `FnPtr` trait that is implemented for all function pointers] (rust-lang/rust#108080) This extends `Debug`, `Pointer`, `Hash`, `PartialEq`, `Eq`, `PartialOrd`, and `Ord` implementations for function pointers with all ABIs. Stabilized APIs --------------- - [`NonZero*::MIN/MAX`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroI8.html#associatedconstant.MIN) - [`BinaryHeap::retain`] (https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.retain) - [`Default for std::collections::binary_heap::IntoIter`] (https://doc.rust-lang.org/stable/std/collections/binary_heap/struct.IntoIter.html) - [`Default for std::collections::btree_map::{IntoIter, Iter, IterMut}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoIter.html) - [`Default for std::collections::btree_map::{IntoKeys, Keys}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoKeys.html) - [`Default for std::collections::btree_map::{IntoValues, Values}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoKeys.html) - [`Default for std::collections::btree_map::Range`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.Range.html) - [`Default for std::collections::btree_set::{IntoIter, Iter}`] (https://doc.rust-lang.org/stable/std/collections/btree_set/struct.IntoIter.html) - [`Default for std::collections::btree_set::Range`] (https://doc.rust-lang.org/stable/std/collections/btree_set/struct.Range.html) - [`Default for std::collections::linked_list::{IntoIter, Iter, IterMut}`] (https://doc.rust-lang.org/stable/alloc/collections/linked_list/struct.IntoIter.html) - [`Default for std::vec::IntoIter`] (https://doc.rust-lang.org/stable/alloc/vec/struct.IntoIter.html#impl-Default-for-IntoIter%3CT,+A%3E) - [`Default for std::iter::Chain`] (https://doc.rust-lang.org/stable/std/iter/struct.Chain.html) - [`Default for std::iter::Cloned`] (https://doc.rust-lang.org/stable/std/iter/struct.Cloned.html) - [`Default for std::iter::Copied`] (https://doc.rust-lang.org/stable/std/iter/struct.Copied.html) - [`Default for std::iter::Enumerate`] (https://doc.rust-lang.org/stable/std/iter/struct.Enumerate.html) - [`Default for std::iter::Flatten`] (https://doc.rust-lang.org/stable/std/iter/struct.Flatten.html) - [`Default for std::iter::Fuse`] (https://doc.rust-lang.org/stable/std/iter/struct.Fuse.html) - [`Default for std::iter::Rev`] (https://doc.rust-lang.org/stable/std/iter/struct.Rev.html) - [`Default for std::slice::Iter`] (https://doc.rust-lang.org/stable/std/slice/struct.Iter.html) - [`Default for std::slice::IterMut`] (https://doc.rust-lang.org/stable/std/slice/struct.IterMut.html) - [`Rc::into_inner`] (https://doc.rust-lang.org/stable/alloc/rc/struct.Rc.html#method.into_inner) - [`Arc::into_inner`] (https://doc.rust-lang.org/stable/alloc/sync/struct.Arc.html#method.into_inner) - [`std::cell::OnceCell`] (https://doc.rust-lang.org/stable/std/cell/struct.OnceCell.html) - [`Option::is_some_and`] (https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.is_some_and) - [`NonNull::slice_from_raw_parts`] (https://doc.rust-lang.org/stable/std/ptr/struct.NonNull.html#method.slice_from_raw_parts) - [`Result::is_ok_and`] (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_ok_and) - [`Result::is_err_and`] (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_err_and) - [`std::sync::atomic::Atomic*::as_ptr`] (https://doc.rust-lang.org/stable/std/sync/atomic/struct.AtomicU8.html#method.as_ptr) - [`std::io::IsTerminal`] (https://doc.rust-lang.org/stable/std/io/trait.IsTerminal.html) - [`std::os::linux::net::SocketAddrExt`] (https://doc.rust-lang.org/stable/std/os/linux/net/trait.SocketAddrExt.html) - [`std::os::unix::net::UnixDatagram::bind_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.bind_addr) - [`std::os::unix::net::UnixDatagram::connect_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.connect_addr) - [`std::os::unix::net::UnixDatagram::send_to_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.send_to_addr) - [`std::os::unix::net::UnixListener::bind_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixListener.html#method.bind_addr) - [`std::path::Path::as_mut_os_str`] (https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.as_mut_os_str) - [`std::sync::OnceLock`] (https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html) Cargo ----- - [Add `CARGO_PKG_README`] (rust-lang/cargo#11645) - [Make `sparse` the default protocol for crates.io] (rust-lang/cargo#11791) - [Accurately show status when downgrading dependencies] (rust-lang/cargo#11839) - [Use registry.default for login/logout] (rust-lang/cargo#11949) - [Stabilize `cargo logout`] (rust-lang/cargo#11950) Misc ---- - [Stabilize rustdoc `--test-run-directory`] (rust-lang/rust#103682) Compatibility Notes ------------------- - [Prevent stable `libtest` from supporting `-Zunstable-options`] (rust-lang/rust#109044) - [Perform const and unsafe checking for expressions in `let _ = expr` position.] (rust-lang/rust#102256) - [WebAssembly targets enable `sign-ext` and `mutable-globals` features in codegen] (rust-lang/rust#109807) This may cause incompatibility with older execution environments. - [Insert alignment checks for pointer dereferences as debug assertions] (rust-lang/rust#98112) This catches undefined behavior at runtime, and may cause existing code to fail. Internal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Upgrade to LLVM 16] (rust-lang/rust#109474) - [Use SipHash-1-3 instead of SipHash-2-4 for StableHasher] (rust-lang/rust#107925)

Pkgsrc changes: * Adjust patches and cargo checksums to new versions. * Add support for NetBSD/riscv64. Upstream changes: Version 1.70.0 (2023-06-01) ========================== Language -------- - [Relax ordering rules for `asm!` operands] (rust-lang/rust#105798) - [Properly allow macro expanded `format_args` invocations to uses captures] (rust-lang/rust#106505) - [Lint ambiguous glob re-exports] (rust-lang/rust#107880) - [Perform const and unsafe checking for expressions in `let _ = expr` position.] (rust-lang/rust#102256) Compiler -------- - [Extend -Cdebuginfo with new options and named aliases] (rust-lang/rust#109808) This provides a smaller version of debuginfo for cases that only need line number information (`-Cdebuginfo=line-tables-only`), which may eventually become the default for `-Cdebuginfo=1`. - [Make `unused_allocation` lint against `Box::new` too] (rust-lang/rust#104363) - [Detect uninhabited types early in const eval] (rust-lang/rust#109435) - [Switch to LLD as default linker for {arm,thumb}v4t-none-eabi] (rust-lang/rust#109721) - [Add tier 3 target `loongarch64-unknown-linux-gnu`] (rust-lang/rust#96971) - [Add tier 3 target for `i586-pc-nto-qnx700`(QNX Neutrino RTOS, version 7.0)] (rust-lang/rust#109173), - [Insert alignment checks for pointer dereferences as debug assertions] (rust-lang/rust#98112) This catches undefined behavior at runtime, and may cause existing code to fail. Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [Document NonZeroXxx layout guarantees] (rust-lang/rust#94786) - [Windows: make `Command` prefer non-verbatim paths] (rust-lang/rust#96391) - [Implement Default for some alloc/core iterators] (rust-lang/rust#99929) - [Fix handling of trailing bare CR in str::lines] (rust-lang/rust#100311) - [allow negative numeric literals in `concat!`] (rust-lang/rust#106844) - [Add documentation about the memory layout of `Cell`] (rust-lang/rust#106921) - [Use `partial_cmp` to implement tuple `lt`/`le`/`ge`/`gt`] (rust-lang/rust#108157) - [Stabilize `atomic_as_ptr`] (rust-lang/rust#108419) - [Stabilize `nonnull_slice_from_raw_parts`] (rust-lang/rust#97506) - [Partial stabilization of `once_cell`] (rust-lang/rust#105587) - [Stabilize `nonzero_min_max`] (rust-lang/rust#106633) - [Flatten/inline format_args!() and (string and int) literal arguments into format_args!()] (rust-lang/rust#106824) - [Stabilize movbe target feature] (rust-lang/rust#107711) - [don't splice from files into pipes in io::copy] (rust-lang/rust#108283) - [Add a builtin unstable `FnPtr` trait that is implemented for all function pointers] (rust-lang/rust#108080) This extends `Debug`, `Pointer`, `Hash`, `PartialEq`, `Eq`, `PartialOrd`, and `Ord` implementations for function pointers with all ABIs. Stabilized APIs --------------- - [`NonZero*::MIN/MAX`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroI8.html#associatedconstant.MIN) - [`BinaryHeap::retain`] (https://doc.rust-lang.org/stable/std/collections/struct.BinaryHeap.html#method.retain) - [`Default for std::collections::binary_heap::IntoIter`] (https://doc.rust-lang.org/stable/std/collections/binary_heap/struct.IntoIter.html) - [`Default for std::collections::btree_map::{IntoIter, Iter, IterMut}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoIter.html) - [`Default for std::collections::btree_map::{IntoKeys, Keys}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoKeys.html) - [`Default for std::collections::btree_map::{IntoValues, Values}`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.IntoKeys.html) - [`Default for std::collections::btree_map::Range`] (https://doc.rust-lang.org/stable/std/collections/btree_map/struct.Range.html) - [`Default for std::collections::btree_set::{IntoIter, Iter}`] (https://doc.rust-lang.org/stable/std/collections/btree_set/struct.IntoIter.html) - [`Default for std::collections::btree_set::Range`] (https://doc.rust-lang.org/stable/std/collections/btree_set/struct.Range.html) - [`Default for std::collections::linked_list::{IntoIter, Iter, IterMut}`] (https://doc.rust-lang.org/stable/alloc/collections/linked_list/struct.IntoIter.html) - [`Default for std::vec::IntoIter`] (https://doc.rust-lang.org/stable/alloc/vec/struct.IntoIter.html#impl-Default-for-IntoIter%3CT,+A%3E) - [`Default for std::iter::Chain`] (https://doc.rust-lang.org/stable/std/iter/struct.Chain.html) - [`Default for std::iter::Cloned`] (https://doc.rust-lang.org/stable/std/iter/struct.Cloned.html) - [`Default for std::iter::Copied`] (https://doc.rust-lang.org/stable/std/iter/struct.Copied.html) - [`Default for std::iter::Enumerate`] (https://doc.rust-lang.org/stable/std/iter/struct.Enumerate.html) - [`Default for std::iter::Flatten`] (https://doc.rust-lang.org/stable/std/iter/struct.Flatten.html) - [`Default for std::iter::Fuse`] (https://doc.rust-lang.org/stable/std/iter/struct.Fuse.html) - [`Default for std::iter::Rev`] (https://doc.rust-lang.org/stable/std/iter/struct.Rev.html) - [`Default for std::slice::Iter`] (https://doc.rust-lang.org/stable/std/slice/struct.Iter.html) - [`Default for std::slice::IterMut`] (https://doc.rust-lang.org/stable/std/slice/struct.IterMut.html) - [`Rc::into_inner`] (https://doc.rust-lang.org/stable/alloc/rc/struct.Rc.html#method.into_inner) - [`Arc::into_inner`] (https://doc.rust-lang.org/stable/alloc/sync/struct.Arc.html#method.into_inner) - [`std::cell::OnceCell`] (https://doc.rust-lang.org/stable/std/cell/struct.OnceCell.html) - [`Option::is_some_and`] (https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.is_some_and) - [`NonNull::slice_from_raw_parts`] (https://doc.rust-lang.org/stable/std/ptr/struct.NonNull.html#method.slice_from_raw_parts) - [`Result::is_ok_and`] (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_ok_and) - [`Result::is_err_and`] (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.is_err_and) - [`std::sync::atomic::Atomic*::as_ptr`] (https://doc.rust-lang.org/stable/std/sync/atomic/struct.AtomicU8.html#method.as_ptr) - [`std::io::IsTerminal`] (https://doc.rust-lang.org/stable/std/io/trait.IsTerminal.html) - [`std::os::linux::net::SocketAddrExt`] (https://doc.rust-lang.org/stable/std/os/linux/net/trait.SocketAddrExt.html) - [`std::os::unix::net::UnixDatagram::bind_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.bind_addr) - [`std::os::unix::net::UnixDatagram::connect_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.connect_addr) - [`std::os::unix::net::UnixDatagram::send_to_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixDatagram.html#method.send_to_addr) - [`std::os::unix::net::UnixListener::bind_addr`] (https://doc.rust-lang.org/stable/std/os/unix/net/struct.UnixListener.html#method.bind_addr) - [`std::path::Path::as_mut_os_str`] (https://doc.rust-lang.org/stable/std/path/struct.Path.html#method.as_mut_os_str) - [`std::sync::OnceLock`] (https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html) Cargo ----- - [Add `CARGO_PKG_README`] (rust-lang/cargo#11645) - [Make `sparse` the default protocol for crates.io] (rust-lang/cargo#11791) - [Accurately show status when downgrading dependencies] (rust-lang/cargo#11839) - [Use registry.default for login/logout] (rust-lang/cargo#11949) - [Stabilize `cargo logout`] (rust-lang/cargo#11950) Misc ---- - [Stabilize rustdoc `--test-run-directory`] (rust-lang/rust#103682) Compatibility Notes ------------------- - [Prevent stable `libtest` from supporting `-Zunstable-options`] (rust-lang/rust#109044) - [Perform const and unsafe checking for expressions in `let _ = expr` position.] (rust-lang/rust#102256) - [WebAssembly targets enable `sign-ext` and `mutable-globals` features in codegen] (rust-lang/rust#109807) This may cause incompatibility with older execution environments. - [Insert alignment checks for pointer dereferences as debug assertions] (rust-lang/rust#98112) This catches undefined behavior at runtime, and may cause existing code to fail. Internal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Upgrade to LLVM 16] (rust-lang/rust#109474) - [Use SipHash-1-3 instead of SipHash-2-4 for StableHasher] (rust-lang/rust#107925)

rustbot assigned eholk Feb 11, 2023

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Feb 11, 2023

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rustbot added perf-regression Performance regression. and removed S-waiting-on-perf Status: Waiting on a perf run to be completed. labels Feb 12, 2023

rustbot added the perf-regression-triaged The performance regression has been triaged. label Feb 12, 2023

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Feb 12, 2023

thomcc and others added 6 commits April 5, 2023 15:59

Fix an assembly test with a hard-coded hash

476737e

Fix a debuginfo test with a hard-coded hash

46fad95

Fix codegen tests with hard-coded hashes

931fd85

Bless rustdoc test with swapped ids

dc04b08

The ids for the multiple `Item` associated type elements are swapped between the first and second impl.

Bless rustdoc-ui test with new errors order

4e235a7

The order in which the multiple errors for the ambiguous intra doc links are printed is different.

Fix function order in an msvc debuginfo test

46a3d28

The function names with const generic parameters are printed in a different order.

lqd force-pushed the sip13 branch from 18aa747 to 46a3d28 Compare April 5, 2023 16:02

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Apr 5, 2023

bors added the merged-by-bors This PR was explicitly merged by bors. label Apr 5, 2023

bors merged commit 2e486be into rust-lang:master Apr 5, 2023
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rustbot added this to the 1.70.0 milestone Apr 5, 2023

bors mentioned this pull request Apr 5, 2023

Refactor unwind in MIR #102906

Merged

thomcc deleted the sip13 branch April 6, 2023 12:43

dccsillag added a commit to dccsillag/typst that referenced this pull request Apr 13, 2023

Change SipHash2-4 -> SipHash1-3

79bfbcd

This seems to significantly improves performance. Inspired by rust-lang/rust#107925

This was referenced Apr 13, 2023

Change SipHash2-4 -> SipHash1-3 typst/typst#780

Merged

Change SipHash2-4 -> SipHash1-3 typst/comemo#1

Merged

laurmaedje pushed a commit to typst/typst that referenced this pull request Apr 19, 2023

Change SipHash2-4 -> SipHash1-3 (#780)

d0afba9

This seems to significantly improves performance. Inspired by rust-lang/rust#107925

elteammate pushed a commit to rabotaem-incorporated/opinionated-typst that referenced this pull request Apr 19, 2023

Change SipHash2-4 -> SipHash1-3 (typst#780)

b855716

This seems to significantly improves performance. Inspired by rust-lang/rust#107925

pravic mentioned this pull request May 29, 2023

Github rejects rendering of RELEASES.md #112058

Closed

tomaka mentioned this pull request May 30, 2023

Use SipHasher13 instead of 24 smol-dot/smoldot#641

Merged

laurmaedje mentioned this pull request Jul 10, 2023

Why use siphasher? typst/comemo#3

Closed

the8472 mentioned this pull request Dec 22, 2023

Collisions in type_id #10389

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Use SipHash-1-3 instead of SipHash-2-4 for StableHasher #107925

Use SipHash-1-3 instead of SipHash-2-4 for StableHasher #107925

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rust-timer commented Apr 5, 2023

Use SipHash-1-3 instead of SipHash-2-4 for StableHasher #107925

Use SipHash-1-3 instead of SipHash-2-4 for StableHasher #107925

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rust-timer commented Feb 12, 2023

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

Instruction count

Max RSS (memory usage)

Cycles

WaffleLapkin commented Feb 12, 2023

cjgillot commented Feb 12, 2023

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Footnotes

thomcc commented Feb 12, 2023

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lqd commented Apr 5, 2023

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rust-timer commented Apr 5, 2023

Overall result: ✅ improvements - no action needed

Instruction count

Max RSS (memory usage)

Cycles