Uh oh!
There was an error while loading. Please reload this page.
Rollup of 6 pull requests - #67220
Merged
Merged
Conversation
Casting the booleans to `i8`s and converting their difference into `Ordering` generates better assembly than casting them to `u8`s and comparing them.
We now only propagate a scalar pair if the Rvalue is a tuple with two scalars. This for example avoids propagating a (u8, u8) value when Rvalue has type `((), u8, u8)` (see the regression test). While this is a correct thing to do, implementation is tricky and will be done later. Fixesrust-lang#66971Fixesrust-lang#66339Fixesrust-lang#67019
…-ord-optimization, r=sfackler Optimize Ord trait implementation for bool Casting the booleans to `i8`s and converting their difference into `Ordering` generates better assembly than casting them to `u8`s and comparing them. Fixesrust-lang#66780 #### Comparison([Godbolt link](https://rust.godbolt.org/z/PjBpvF)) ##### Old assembly: ```asm example::boolean_cmp: mov ecx, edi xor ecx, esi test esi, esi mov eax, 255 cmove eax, ecx test edi, edi cmovne eax, ecx ret ``` ##### New assembly: ```asm example::boolean_cmp: mov eax, edi sub al, sil ret ``` ##### Old LLVM-MCA statistics: ``` Iterations: 100 Instructions: 800 Total Cycles: 234 Total uOps: 1000 Dispatch Width: 6 uOps Per Cycle: 4.27 IPC: 3.42 Block RThroughput: 1.7 ``` ##### New LLVM-MCA statistics: ``` Iterations: 100 Instructions: 300 Total Cycles: 110 Total uOps: 500 Dispatch Width: 6 uOps Per Cycle: 4.55 IPC: 2.73 Block RThroughput: 1.0 ```
Fix constant propagation for scalar pairs We now only propagate a scalar pair if the Rvalue is a tuple with two scalars. This for example avoids propagating a (u8, u8) value when Rvalue has type `((), u8, u8)` (see the regression test). While this is a correct thing to do, implementation is tricky and will be done later. Fixesrust-lang#66971Fixesrust-lang#66339Fixesrust-lang#67019
Add options to --extern flag. This changes the `--extern` flag so that it can take a series of options that changes its behavior. The general syntax is `[opts ':'] name ['=' path]` where `opts` is a comma separated list of options. Two options are supported, `priv` which replaces `--extern-private` and `noprelude` which avoids adding the crate to the extern prelude. ```text --extern priv:mylib=/path/to/libmylib.rlib --extern noprelude:alloc=/path/to/liballoc.rlib ``` `noprelude` is to be used by Cargo's build-std feature in order to use `--extern` to reference standard library crates. This also includes a second commit which adds the `aux-crate` directive to compiletest. I can split this off into a separate PR if desired, but it helps with defining these kinds of tests. It is based on rust-lang#54020, and can be used in the future to replace and simplify some of the Makefile tests.
…=oli-obk Ensure that panicking in constants eventually errors based on rust-lang#67134closesrust-lang#66975 r? @oli-obk
Remove `checked_add` in `Layout::repeat`
Make `publish_toolstate.sh` executable It causes a failure on master ([log](https://dev.azure.com/rust-lang/rust/_build/results?buildId=15627)). r? @pietroalbini CC: @Mark-Simulacrum
Centril
commented
Dec 11, 2019
ContributorAuthor
@bors r+ p=6 rollup=never |
bors
commented
Dec 11, 2019
Collaborator
📌 Commit f6ceef5 has been approved by |
Centril
commented
Dec 11, 2019
ContributorAuthor
@bors p=2000 |
bors
commented
Dec 11, 2019
Collaborator
bors added a commit
that referenced
this pull request
Dec 11, 2019
Rollup of 6 pull requests Successful merges: - #66881 (Optimize Ord trait implementation for bool) - #67015 (Fix constant propagation for scalar pairs) - #67074 (Add options to --extern flag.) - #67164 (Ensure that panicking in constants eventually errors) - #67174 (Remove `checked_add` in `Layout::repeat`) - #67205 (Make `publish_toolstate.sh` executable) Failed merges: r? @ghost
bors
commented
Dec 11, 2019
Collaborator
☀️ Test successful - checks-azure |
Merged
eddyb
commented
Dec 12, 2019
Contributor
Before I forget about it, I think something in this rollup caused a noticeable regression. cc @rust-lang/wg-compiler-performance |
nikomatsakis
commented
Dec 12, 2019
Contributor
Should we file an issue to track that ? |
nnethercote
commented
Dec 13, 2019
Contributor
@oli-obk: Could #67164 have caused the regression? @krishna-veerareddy: Could #66881 have cause the regression? @ehuss: Could #67074 have caused the regression? #67174 and #67205 seem very unlikely to be the cause. I just tried to work out which commit caused the problem but failed; every revision I tried (even blatantly pre-merge ones) had the same post-regression numbers on |
krishna-veerareddy
commented
Dec 14, 2019
Contributor
@nnethercote Hey sorry for the late response. It's unlikely that 66881 could have caused a regression since it has to do with boolean comparision which isn't used quite often and if anything the fix should have reduced the instruction count but I could be wrong. Is this still an unresolved issue? |
oli-obk
commented
Dec 14, 2019
Contributor
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for freeto join this conversation on GitHub.
Already have an account?
Sign in to comment
12 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Successful merges:
checked_addinLayout::repeat#67174 (Removechecked_addinLayout::repeat)publish_toolstate.shexecutable #67205 (Makepublish_toolstate.shexecutable)Failed merges:
r? @ghost