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756 commits

Author SHA1 Message Date
Guillaume Boisseau
e3c0158788
Rollup merge of #120504 - kornelski:try_with_capacity, r=Amanieu
Vec::try_with_capacity

Related to #91913

Implements try_with_capacity for `Vec`, `VecDeque`, and `String`. I can follow it up with more collections if desired.

`Vec::try_with_capacity()` is functionally equivalent to the current stable:

```rust
let mut v = Vec::new();
v.try_reserve_exact(n)?
```

However, `try_reserve` calls non-inlined `finish_grow`, which requires old and new `Layout`, and is designed to reallocate memory. There is benefit to using `try_with_capacity`, besides syntax convenience, because it generates much smaller code at the call site with a direct call to the allocator. There's codegen test included.

It's also a very desirable functionality for users of `no_global_oom_handling` (Rust-for-Linux), since it makes a very commonly used function available in that environment (`with_capacity` is used much more frequently than all `(try_)reserve(_exact)`).
2024-03-09 21:40:06 +01:00
Urgau
cc38c1e9cb Add #[inline] to BTreeMap::new constructor 2024-03-06 19:14:03 +01:00
Kornel
78fb977d6b try_with_capacity for Vec, VecDeque, String
#91913
2024-03-01 18:24:02 +00:00
Alexander
fb8ac06477 remove hidden use of Global 2024-03-01 11:51:28 +00:00
cui fliter
824d75c22e remove repetitive words
Signed-off-by: cui fliter <imcusg@gmail.com>
2024-02-23 18:26:01 +08:00
Esteban Küber
e5b3c7ef14 Add rustc_confusables annotations to some stdlib APIs
Help with common API confusion, like asking for `push` when the data structure really has `append`.

```
error[E0599]: no method named `size` found for struct `Vec<{integer}>` in the current scope
  --> $DIR/rustc_confusables_std_cases.rs:17:7
   |
LL |     x.size();
   |       ^^^^
   |
help: you might have meant to use `len`
   |
LL |     x.len();
   |       ~~~
help: there is a method with a similar name
   |
LL |     x.resize();
   |       ~~~~~~
```

#59450
2024-02-22 18:04:55 +00:00
bors
158f00a1c5 Auto merge of #118264 - lukas-code:optimized-draining, r=the8472
Optimize `VecDeque::drain` for (half-)open ranges

The most common use cases of `VecDeque::drain` consume either the entire queue or elements from the front or back.[^1] This PR makes these operations faster by optimizing the generated code of the destructor of the drain:

* `.drain(..)` is now the same as `.clear()`.
* `.drain(n..)` is now (almost[^2]) the same as `.truncate(n)`.
* `.drain(..n)` is now an efficient "advance" function. This operation is not provided by a dedicated function and optimizing it is my main motivation for this PR.

Previously, all of these cases generated a function call to the destructor of the `DropGuard`, emitting a lot of unused machine code as well as unnecessary branches and loads/stores of stack variables.

There are no algorithmic changes in this PR, but it simplifies the code enough to allow LLVM to recognize the special cases and optimize accordingly. Most notably, it allows elimination of the rather large [`wrap_copy`] function.

Some [rudimentary microbenchmarks][benches] show a performance improvement of **~3x-4x** on my machine for the special cases and roughly equal performance for the general case.

Best reviewed commit by commit.

[^1]: source: GitHub code search: [full range `drain(..)` = 7.5k results][full], [from front `drain(..n)` = 3.2k results][front], [from back `drain(n..)` = 1.6k results][back], [from middle `drain(n..m)` = <500 results][middle]

[^2]: `.drain(0..)` and `.clear()` reset the head to 0, but `.truncate(0)` does not.

[full]: https://github.com/search?type=code&q=%2FVecDeque%28.%7C%5Cn%29%2B%5C.drain%5C%280%3F%5C.%5C.%5C%29%2F+lang%3ARust
[front]: https://github.com/search?type=code&q=%2FVecDeque%28.%7C%5Cn%29%2B%5C.drain%5C%280%3F%5C.%5C.%5B%5E%29%5D.*%5C%29%2F+lang%3ARust
[back]: https://github.com/search?type=code&q=%2FVecDeque%28.%7C%5Cn%29%2B%5C.drain%5C%28%5B%5E0%5D.*%5C.%5C.%5C%29%2F+lang%3ARust
[middle]: https://github.com/search?type=code&q=%2FVecDeque%28.%7C%5Cn%29%2B%5C.drain%5C%28%5B%5E0%5D.*%5C.%5C.%5B%5E%29%5D.*%5C%29%2F+lang%3ARust
[`wrap_copy`]: 4fd68eb47b/library/alloc/src/collections/vec_deque/mod.rs (L262-L391)
[benches]: https://gist.github.com/lukas-code/c97bd707d074c4cc31f241edbc7fd2a2

<details>
<summary>generated assembly</summary>

before:
```asm
clear:
	sub rsp, 40
	mov rax, qword ptr [rdi + 24]
	mov qword ptr [rdi + 24], 0
	mov qword ptr [rsp], rdi
	mov qword ptr [rsp + 8], rax
	xorps xmm0, xmm0
	movups xmmword ptr [rsp + 16], xmm0
	mov qword ptr [rsp + 32], rax
	test rax, rax
	je .LBB1_2
	mov rcx, qword ptr [rdi]
	mov rdx, qword ptr [rdi + 16]
	xor esi, esi
	cmp rdx, rcx
	cmovae rsi, rcx
	sub rdx, rsi
	mov rsi, rcx
	sub rsi, rdx
	lea rdi, [rdx + rax]
	cmp rsi, rax
	cmovb rdi, rcx
	sub rdi, rdx
	mov qword ptr [rsp + 16], rdi
	mov qword ptr [rsp + 32], 0
.LBB1_2:
	mov rdi, rsp
	call core::ptr::drop_in_place<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<i32,alloc::alloc::Global>>
	add rsp, 40
	ret

truncate:
	mov rax, qword ptr [rdi + 24]
	sub rax, rsi
	jbe .LBB2_2
	sub rsp, 40
	mov qword ptr [rdi + 24], rsi
	mov qword ptr [rsp], rdi
	mov qword ptr [rsp + 8], rax
	mov rcx, qword ptr [rdi]
	mov rdx, qword ptr [rdi + 16]
	add rdx, rsi
	xor edi, edi
	cmp rdx, rcx
	cmovae rdi, rcx
	mov qword ptr [rsp + 24], 0
	sub rdx, rdi
	mov rdi, rcx
	sub rdi, rdx
	lea r8, [rdx + rax]
	cmp rdi, rax
	cmovb r8, rcx
	sub rsi, rdx
	add rsi, r8
	mov qword ptr [rsp + 16], rsi
	mov qword ptr [rsp + 32], 0
	mov rdi, rsp
	call core::ptr::drop_in_place<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<i32,alloc::alloc::Global>>
	add rsp, 40

advance:
	mov rcx, qword ptr [rdi + 24]
	mov rax, rcx
	sub rax, rsi
	jbe .LBB3_1
	sub rsp, 40
	mov qword ptr [rdi + 24], 0
	mov qword ptr [rsp], rdi
	mov qword ptr [rsp + 8], rsi
	mov qword ptr [rsp + 16], 0
	mov qword ptr [rsp + 24], rax
	mov qword ptr [rsp + 32], rsi
	test rsi, rsi
	je .LBB3_6
	mov rax, qword ptr [rdi]
	mov rcx, qword ptr [rdi + 16]
	xor edx, edx
	cmp rcx, rax
	cmovae rdx, rax
	sub rcx, rdx
	mov rdx, rax
	sub rdx, rcx
	lea rdi, [rcx + rsi]
	cmp rdx, rsi
	cmovb rdi, rax
	sub rdi, rcx
	mov qword ptr [rsp + 16], rdi
	mov qword ptr [rsp + 32], 0
.LBB3_6:
	mov rdi, rsp
	call core::ptr::drop_in_place<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<i32,alloc::alloc::Global>>
	add rsp, 40
	ret
.LBB3_1:
	test rcx, rcx
	je .LBB3_3
	mov qword ptr [rdi + 24], 0
.LBB3_3:
	mov qword ptr [rdi + 16], 0
	ret

remove:
	sub rsp, 40
	cmp rdx, rsi
	jb .LBB4_5
	mov rax, qword ptr [rdi + 24]
	mov rcx, rax
	sub rcx, rdx
	jb .LBB4_6
	mov qword ptr [rdi + 24], rsi
	mov qword ptr [rsp], rdi
	sub rdx, rsi
	mov qword ptr [rsp + 8], rdx
	mov qword ptr [rsp + 16], rsi
	mov qword ptr [rsp + 24], rcx
	mov qword ptr [rsp + 32], rdx
	je .LBB4_4
	mov rax, qword ptr [rdi]
	mov rcx, qword ptr [rdi + 16]
	add rcx, rsi
	xor edi, edi
	cmp rcx, rax
	cmovae rdi, rax
	sub rcx, rdi
	mov rdi, rax
	sub rdi, rcx
	lea r8, [rcx + rdx]
	cmp rdi, rdx
	cmovb r8, rax
	sub rsi, rcx
	add rsi, r8
	mov qword ptr [rsp + 16], rsi
	mov qword ptr [rsp + 32], 0
.LBB4_4:
	mov rdi, rsp
	call core::ptr::drop_in_place<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<i32,alloc::alloc::Global>>
	add rsp, 40
	ret
.LBB4_5:
	lea rax, [rip + .L__unnamed_2]
	mov rdi, rsi
	mov rsi, rdx
	mov rdx, rax
	call qword ptr [rip + core::slice::index::slice_index_order_fail@GOTPCREL]
.LBB4_6:
	lea rcx, [rip + .L__unnamed_2]
	mov rdi, rdx
	mov rsi, rax
	mov rdx, rcx
	call qword ptr [rip + core::slice::index::slice_end_index_len_fail@GOTPCREL]

core::ptr::drop_in_place<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<i32,alloc::alloc::Global>>:
	push rbp
	push r15
	push r14
	push r13
	push r12
	push rbx
	sub rsp, 24
	mov rsi, qword ptr [rdi + 32]
	test rsi, rsi
	je .LBB0_2
	mov rax, qword ptr [rdi + 16]
	add rsi, rax
	jb .LBB0_45
.LBB0_2:
	mov r13, qword ptr [rdi]
	mov rbp, qword ptr [rdi + 8]
	mov rbx, qword ptr [r13 + 24]
	lea r12, [rbx + rbp]
	mov r15, qword ptr [rdi + 24]
	lea rsi, [r15 + r12]
	test rbx, rbx
	je .LBB0_10
	test r15, r15
	je .LBB0_42
	cmp rbx, r15
	jbe .LBB0_12
	mov r14, qword ptr [r13]
	mov rax, qword ptr [r13 + 16]
	add r12, rax
	xor ecx, ecx
	cmp r12, r14
	mov rdx, r14
	cmovb rdx, rcx
	sub r12, rdx
	add rbx, rax
	cmp rbx, r14
	cmovae rcx, r14
	sub rbx, rcx
	mov rcx, rbx
	sub rcx, r12
	je .LBB0_42
	mov rdi, qword ptr [r13 + 8]
	mov rax, rcx
	add rax, r14
	cmovae rax, rcx
	mov r8, r14
	sub r8, r12
	mov rcx, r14
	sub rcx, rbx
	mov rdx, r15
	sub rdx, r8
	mov qword ptr [rsp + 16], rsi
	jbe .LBB0_18
	cmp rax, r15
	jae .LBB0_24
	mov rdx, r15
	sub rdx, r8
	shl rdx, 2
	cmp r15, rcx
	jbe .LBB0_30
	sub r8, rcx
	mov qword ptr [rsp], rdi
	mov rax, qword ptr [rsp]
	lea rdi, [rax + 4*r8]
	mov rsi, qword ptr [rsp]
	mov qword ptr [rsp + 8], rcx
	mov r15, r8
	call qword ptr [rip + memmove@GOTPCREL]
	sub r14, r15
	mov rax, qword ptr [rsp]
	lea rsi, [rax + 4*r14]
	shl r15, 2
	mov rdi, qword ptr [rsp]
	mov rdx, r15
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, qword ptr [rsp]
	lea rsi, [rdi + 4*r12]
	lea rdi, [rdi + 4*rbx]
	mov r15, qword ptr [rsp + 8]
	jmp .LBB0_36
.LBB0_10:
	test r15, r15
	je .LBB0_17
	mov rax, qword ptr [r13]
	sub rsi, rbp
	add rbp, qword ptr [r13 + 16]
	xor ecx, ecx
	cmp rbp, rax
	cmovae rcx, rax
	sub rbp, rcx
	mov qword ptr [r13 + 16], rbp
	jmp .LBB0_43
.LBB0_12:
	mov rdx, qword ptr [r13 + 16]
	mov r15, qword ptr [r13]
	lea rax, [rdx + rbp]
	xor ecx, ecx
	cmp rax, r15
	cmovae rcx, r15
	mov r12, rax
	sub r12, rcx
	mov rcx, r12
	sub rcx, rdx
	je .LBB0_41
	mov rdi, qword ptr [r13 + 8]
	mov rax, rcx
	add rax, r15
	cmovae rax, rcx
	mov r8, r15
	sub r8, rdx
	mov rcx, r15
	sub rcx, r12
	mov r14, rbx
	sub r14, r8
	mov qword ptr [rsp + 16], rsi
	jbe .LBB0_21
	cmp rax, rbx
	jae .LBB0_26
	mov qword ptr [rsp], rdx
	mov rdx, rbx
	sub rdx, r8
	shl rdx, 2
	cmp rbx, rcx
	jbe .LBB0_32
	sub r8, rcx
	mov rbx, rdi
	lea rdi, [rdi + 4*r8]
	mov rsi, rbx
	mov qword ptr [rsp + 8], rcx
	mov r14, r8
	call qword ptr [rip + memmove@GOTPCREL]
	sub r15, r14
	lea rsi, [rbx + 4*r15]
	shl r14, 2
	mov rdi, rbx
	mov rdx, r14
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, rbx
	mov rax, qword ptr [rsp]
	lea rsi, [rbx + 4*rax]
	lea rdi, [rbx + 4*r12]
	mov rbx, qword ptr [rsp + 8]
	jmp .LBB0_40
.LBB0_17:
	xorps xmm0, xmm0
	movups xmmword ptr [r13 + 16], xmm0
	jmp .LBB0_44
.LBB0_18:
	mov r14, r15
	sub r14, rcx
	jbe .LBB0_28
	cmp rax, r15
	jae .LBB0_33
	lea rax, [rcx + r12]
	sub r15, rcx
	lea rsi, [rdi + 4*rax]
	shl r15, 2
	mov r14, rdi
	mov rdx, r15
	mov r15, rcx
	jmp .LBB0_31
.LBB0_21:
	mov r14, rbx
	sub r14, rcx
	jbe .LBB0_29
	cmp rax, rbx
	jae .LBB0_34
	lea rax, [rcx + rdx]
	sub rbx, rcx
	lea rsi, [rdi + 4*rax]
	shl rbx, 2
	mov r14, rdi
	mov r15, rdx
	mov rdx, rbx
	mov rbx, rcx
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r14
	lea rsi, [r14 + 4*r15]
	lea rdi, [r14 + 4*r12]
	jmp .LBB0_40
.LBB0_24:
	sub r15, rcx
	jbe .LBB0_35
	sub rcx, r8
	mov qword ptr [rsp + 8], rcx
	lea rsi, [rdi + 4*r12]
	mov r12, rdi
	lea rdi, [rdi + 4*rbx]
	lea rdx, [4*r8]
	mov r14, r8
	call qword ptr [rip + memmove@GOTPCREL]
	add r14, rbx
	lea rdi, [r12 + 4*r14]
	mov rbx, qword ptr [rsp + 8]
	lea rdx, [4*rbx]
	mov rsi, r12
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r12
	lea rsi, [r12 + 4*rbx]
	jmp .LBB0_36
.LBB0_26:
	sub rbx, rcx
	jbe .LBB0_37
	sub rcx, r8
	lea rsi, [rdi + 4*rdx]
	mov r15, rdi
	lea rdi, [rdi + 4*r12]
	lea rdx, [4*r8]
	mov r14, rcx
	mov qword ptr [rsp], r8
	call qword ptr [rip + memmove@GOTPCREL]
	add r12, qword ptr [rsp]
	lea rdi, [r15 + 4*r12]
	lea rdx, [4*r14]
	mov rsi, r15
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r15
	lea rsi, [r15 + 4*r14]
	jmp .LBB0_40
.LBB0_28:
	lea rsi, [rdi + 4*r12]
	lea rdi, [rdi + 4*rbx]
	jmp .LBB0_36
.LBB0_29:
	lea rsi, [rdi + 4*rdx]
	lea rdi, [rdi + 4*r12]
	jmp .LBB0_40
.LBB0_30:
	lea rax, [r8 + rbx]
	mov r14, rdi
	lea rdi, [rdi + 4*rax]
	mov rsi, r14
	mov r15, r8
.LBB0_31:
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r14
	lea rsi, [r14 + 4*r12]
	lea rdi, [r14 + 4*rbx]
	jmp .LBB0_36
.LBB0_32:
	lea rax, [r12 + r8]
	mov rbx, rdi
	lea rdi, [rdi + 4*rax]
	mov rsi, rbx
	mov r14, r8
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, rbx
	mov rax, qword ptr [rsp]
	lea rsi, [rbx + 4*rax]
	jmp .LBB0_38
.LBB0_33:
	lea rsi, [rdi + 4*r12]
	mov r15, rdi
	lea rdi, [rdi + 4*rbx]
	lea rdx, [4*rcx]
	mov rbx, rcx
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r15
	add rbx, r12
	lea rsi, [r15 + 4*rbx]
	mov r15, r14
	jmp .LBB0_36
.LBB0_34:
	lea rsi, [rdi + 4*rdx]
	mov rbx, rdi
	lea rdi, [rdi + 4*r12]
	mov r15, rdx
	lea rdx, [4*rcx]
	mov r12, rcx
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, rbx
	add r12, r15
	lea rsi, [rbx + 4*r12]
	jmp .LBB0_39
.LBB0_35:
	lea rsi, [rdi + 4*r12]
	mov r14, rdi
	lea rdi, [rdi + 4*rbx]
	mov r12, rdx
	lea rdx, [4*r8]
	mov r15, r8
	call qword ptr [rip + memmove@GOTPCREL]
	add r15, rbx
	mov rsi, r14
	lea rdi, [r14 + 4*r15]
	mov r15, r12
.LBB0_36:
	shl r15, 2
	mov rdx, r15
	call qword ptr [rip + memmove@GOTPCREL]
	mov rsi, qword ptr [rsp + 16]
	jmp .LBB0_42
.LBB0_37:
	lea rsi, [rdi + 4*rdx]
	mov rbx, rdi
	lea rdi, [rdi + 4*r12]
	lea rdx, [4*r8]
	mov r15, r8
	call qword ptr [rip + memmove@GOTPCREL]
	add r12, r15
	mov rsi, rbx
.LBB0_38:
	lea rdi, [rbx + 4*r12]
.LBB0_39:
	mov rbx, r14
.LBB0_40:
	shl rbx, 2
	mov rdx, rbx
	call qword ptr [rip + memmove@GOTPCREL]
	mov r15, qword ptr [r13]
	mov rax, qword ptr [r13 + 16]
	add rax, rbp
	mov rsi, qword ptr [rsp + 16]
.LBB0_41:
	xor ecx, ecx
	cmp rax, r15
	cmovae rcx, r15
	sub rax, rcx
	mov qword ptr [r13 + 16], rax
.LBB0_42:
	sub rsi, rbp
.LBB0_43:
	mov qword ptr [r13 + 24], rsi
.LBB0_44:
	add rsp, 24
	pop rbx
	pop r12
	pop r13
	pop r14
	pop r15
	pop rbp
	ret
.LBB0_45:
	lea rdx, [rip + .L__unnamed_1]
	mov rdi, rax
	call qword ptr [rip + core::slice::index::slice_index_order_fail@GOTPCREL]
```

after:
```asm
clear:
	movups xmmword ptr [rdi + 16], xmm0
	ret

truncate:
	cmp qword ptr [rdi + 24], rsi
	jbe .LBB2_4
	test rsi, rsi
	jne .LBB2_3
	mov qword ptr [rdi + 16], 0
.LBB2_3:
	mov qword ptr [rdi + 24], rsi
.LBB2_4:
	ret

advance:
	mov rcx, qword ptr [rdi + 24]
	mov rax, rcx
	sub rax, rsi
	jbe .LBB3_1
	mov rcx, qword ptr [rdi]
	add rsi, qword ptr [rdi + 16]
	xor edx, edx
	cmp rsi, rcx
	cmovae rdx, rcx
	sub rsi, rdx
	mov qword ptr [rdi + 16], rsi
	mov qword ptr [rdi + 24], rax
	ret
.LBB3_1:
	test rcx, rcx
	je .LBB3_3
	mov qword ptr [rdi + 24], 0
.LBB3_3:
	mov qword ptr [rdi + 16], 0
	ret

remove:
	push rbp
	push r15
	push r14
	push r13
	push r12
	push rbx
	push rax
	mov r15, rsi
	mov r14, rdx
	sub r14, rsi
	jb .LBB4_9
	mov rbx, rdi
	mov r12, qword ptr [rdi + 24]
	mov r13, r12
	sub r13, rdx
	jb .LBB4_10
	mov qword ptr [rbx + 24], r15
	mov rbp, r12
	sub rbp, r14
	test r15, r15
	je .LBB4_4
	cmp rbp, r15
	jne .LBB4_11
.LBB4_4:
	cmp r12, r14
	jne .LBB4_6
.LBB4_5:
	mov qword ptr [rbx + 16], 0
	jmp .LBB4_8
.LBB4_11:
	mov rdi, rbx
	mov rsi, r14
	mov rdx, r15
	mov rcx, r13
	call <<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<T,A> as core::ops::drop::Drop>::drop::copy_data
	cmp r12, r14
	je .LBB4_5
.LBB4_6:
	cmp r13, r15
	jbe .LBB4_8
	mov rax, qword ptr [rbx]
	add r14, qword ptr [rbx + 16]
	xor ecx, ecx
	cmp r14, rax
	cmovae rcx, rax
	sub r14, rcx
	mov qword ptr [rbx + 16], r14
.LBB4_8:
	mov qword ptr [rbx + 24], rbp
	add rsp, 8
	pop rbx
	pop r12
	pop r13
	pop r14
	pop r15
	pop rbp
	ret
.LBB4_9:
	lea rax, [rip + .L__unnamed_1]
	mov rdi, r15
	mov rsi, rdx
	mov rdx, rax
	call qword ptr [rip + core::slice::index::slice_index_order_fail@GOTPCREL]
.LBB4_10:
	lea rax, [rip + .L__unnamed_1]
	mov rdi, rdx
	mov rsi, r12
	mov rdx, rax
	call qword ptr [rip + core::slice::index::slice_end_index_len_fail@GOTPCREL]

<<alloc::collections::vec_deque::drain::Drain<T,A> as core::ops::drop::Drop>::drop::DropGuard<T,A> as core::ops::drop::Drop>::drop::copy_data:
	push rbp
	push r15
	push r14
	push r13
	push r12
	push rbx
	push rax
	mov r14, rsi
	cmp rdx, rcx
	jae .LBB0_1
	mov r12, qword ptr [rdi]
	mov rax, qword ptr [rdi + 16]
	add r14, rax
	xor ecx, ecx
	cmp r14, r12
	cmovae rcx, r12
	sub r14, rcx
	mov r15, rdx
	mov r13, r14
	mov r14, rax
	mov rcx, r13
	sub rcx, r14
	je .LBB0_18
.LBB0_4:
	mov rdi, qword ptr [rdi + 8]
	mov rax, rcx
	add rax, r12
	cmovae rax, rcx
	mov rbx, r12
	sub rbx, r14
	mov rcx, r12
	sub rcx, r13
	mov rbp, r15
	sub rbp, rbx
	jbe .LBB0_5
	cmp rax, r15
	jae .LBB0_12
	mov rdx, r15
	sub rdx, rbx
	shl rdx, 2
	cmp r15, rcx
	jbe .LBB0_16
	sub rbx, rcx
	mov rbp, rdi
	lea rdi, [rdi + 4*rbx]
	mov r15, qword ptr [rip + memmove@GOTPCREL]
	mov rsi, rbp
	mov qword ptr [rsp], rcx
	call r15
	sub r12, rbx
	lea rsi, [4*r12]
	add rsi, rbp
	shl rbx, 2
	mov rdi, rbp
	mov rdx, rbx
	call r15
	mov rdi, rbp
	lea rsi, [4*r14]
	add rsi, rbp
	lea rdi, [4*r13]
	add rdi, rbp
	mov r15, qword ptr [rsp]
	jmp .LBB0_7
.LBB0_1:
	mov r15, rcx
	add r14, rdx
	mov r12, qword ptr [rdi]
	mov r13, qword ptr [rdi + 16]
	add r14, r13
	xor eax, eax
	cmp r14, r12
	mov rcx, r12
	cmovb rcx, rax
	sub r14, rcx
	add r13, rdx
	cmp r13, r12
	cmovae rax, r12
	sub r13, rax
	mov rcx, r13
	sub rcx, r14
	jne .LBB0_4
.LBB0_18:
	add rsp, 8
	pop rbx
	pop r12
	pop r13
	pop r14
	pop r15
	pop rbp
	ret
.LBB0_5:
	mov rbx, r15
	sub rbx, rcx
	jbe .LBB0_6
	cmp rax, r15
	jae .LBB0_9
	lea rax, [rcx + r14]
	sub r15, rcx
	lea rsi, [rdi + 4*rax]
	shl r15, 2
	mov rbx, rdi
	mov rdx, r15
	mov r15, rcx
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, rbx
	lea rsi, [rbx + 4*r14]
	lea rdi, [rbx + 4*r13]
	jmp .LBB0_7
.LBB0_12:
	sub r15, rcx
	jbe .LBB0_13
	sub rcx, rbx
	lea rsi, [rdi + 4*r14]
	mov r12, rdi
	lea rdi, [rdi + 4*r13]
	lea rdx, [4*rbx]
	mov r14, qword ptr [rip + memmove@GOTPCREL]
	mov rbp, rcx
	call r14
	add rbx, r13
	lea rdi, [r12 + 4*rbx]
	lea rdx, [4*rbp]
	mov rsi, r12
	call r14
	mov rdi, r12
	lea rsi, [r12 + 4*rbp]
	jmp .LBB0_7
.LBB0_6:
	lea rsi, [rdi + 4*r14]
	lea rdi, [rdi + 4*r13]
	jmp .LBB0_7
.LBB0_16:
	lea rax, [rbx + r13]
	mov r15, rdi
	lea rdi, [rdi + 4*rax]
	mov rsi, r15
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r15
	lea rsi, [r15 + 4*r14]
	lea rdi, [r15 + 4*r13]
	mov r15, rbx
	jmp .LBB0_7
.LBB0_9:
	lea rsi, [rdi + 4*r14]
	mov r15, rdi
	lea rdi, [rdi + 4*r13]
	lea rdx, [4*rcx]
	mov r12, rcx
	call qword ptr [rip + memmove@GOTPCREL]
	mov rdi, r15
	add r12, r14
	lea rsi, [r15 + 4*r12]
	mov r15, rbx
	jmp .LBB0_7
.LBB0_13:
	lea rsi, [rdi + 4*r14]
	mov r14, rdi
	lea rdi, [rdi + 4*r13]
	lea rdx, [4*rbx]
	call qword ptr [rip + memmove@GOTPCREL]
	add rbx, r13
	mov rsi, r14
	lea rdi, [r14 + 4*rbx]
	mov r15, rbp
.LBB0_7:
	shl r15, 2
	mov rdx, r15
	add rsp, 8
	pop rbx
	pop r12
	pop r13
	pop r14
	pop r15
	pop rbp
	jmp qword ptr [rip + memmove@GOTPCREL]
```

</details>
2024-02-18 00:03:39 +00:00
Matthias Krüger
cb371797d6
Rollup merge of #121149 - SebastianJL:patch-1, r=Mark-Simulacrum
Fix typo in VecDeque::handle_capacity_increase() doc comment.

Strategies B and C both show a full buffer before the capacity increase, while strategy A had one empty element left. Filled the last element in.
2024-02-17 18:47:41 +01:00
Lukas Markeffsky
5d989770f2 address review comments 2024-02-16 13:11:05 +01:00
Lukas Markeffsky
b6702939f7 outline large copies 2024-02-16 13:10:52 +01:00
Lukas Markeffsky
1e3849aed0 reduce branchiness 2024-02-16 13:10:52 +01:00
Lukas Markeffsky
500ef67877 reduce amount of math 2024-02-16 13:10:52 +01:00
Lukas Markeffsky
ec95d259e4 simplify codegen for trivially droppable types 2024-02-16 13:10:52 +01:00
bors
1be468815c Auto merge of #120486 - reitermarkus:use-generic-nonzero, r=dtolnay
Use generic `NonZero` internally.

Tracking issue: https://github.com/rust-lang/rust/issues/120257
2024-02-16 07:46:31 +00:00
Johannes Lade
17066870cd
Fix typo in VecDeque::handle_capacity_increase() doc comment.
Strategies B and C both show a full buffer before the capacity increase, while strategy A had one empty element left. Filled the last element in.
2024-02-15 17:33:37 +01:00
Guillaume Gomez
472c820eb3
Rollup merge of #120505 - Amanieu:fix-btreemap-cursor-remove, r=m-ou-se
Fix BTreeMap's Cursor::remove_{next,prev}

These would incorrectly leave `current` as `None` after a failed attempt to remove an element (due to the cursor already being at the start/end).
2024-02-15 14:33:00 +01:00
Markus Reiter
a90cc05233
Replace NonZero::<_>::new with NonZero::new. 2024-02-15 08:09:42 +01:00
Markus Reiter
746a58d435
Use generic NonZero internally. 2024-02-15 08:09:42 +01:00
ripytide
f34d9da7db
fix intra-doc links 2024-02-11 20:26:05 +00:00
ripytide
f415339052
fix incorrect doctest 2024-02-11 16:18:40 +00:00
ripytide
792fa24595
improve btree_cursors functions documentation 2024-02-11 15:51:07 +00:00
Amanieu d'Antras
adb7607189 Fix BTreeMap's Cursor::remove_{next,prev}
These would incorrectly leave `current` as `None` after a failed attempt
to remove an element (due to the cursor already being at the start/end).
2024-01-30 17:51:20 +00:00
Matthias Krüger
37f02320bc
Rollup merge of #118208 - Amanieu:btree_cursor2, r=dtolnay
Rewrite the BTreeMap cursor API using gaps

Tracking issue: #107540

Currently, a `Cursor` points to a single element in the tree, and allows moving to the next or previous element while mutating the tree. However this was found to be confusing and hard to use.

This PR completely refactors cursors to instead point to a gap between two elements in the tree. This eliminates the need for a "ghost" element that exists after the last element and before the first one. Additionally, `upper_bound` and `lower_bound` now have a much clearer meaning.

The ability to mutate keys is also factored out into a separate `CursorMutKey` type which is unsafe to create. This makes the API easier to use since it avoids duplicated versions of each method with and without key mutation.

API summary:

```rust
impl<K, V> BTreeMap<K, V> {
    fn lower_bound<Q>(&self, bound: Bound<&Q>) -> Cursor<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn lower_bound_mut<Q>(&mut self, bound: Bound<&Q>) -> CursorMut<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn upper_bound<Q>(&self, bound: Bound<&Q>) -> Cursor<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn upper_bound_mut<Q>(&mut self, bound: Bound<&Q>) -> CursorMut<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
}

struct Cursor<'a, K: 'a, V: 'a>;

impl<'a, K, V> Cursor<'a, K, V> {
    fn next(&mut self) -> Option<(&'a K, &'a V)>;
    fn prev(&mut self) -> Option<(&'a K, &'a V)>;
    fn peek_next(&self) -> Option<(&'a K, &'a V)>;
    fn peek_prev(&self) -> Option<(&'a K, &'a V)>;
}

struct CursorMut<'a, K: 'a, V: 'a>;

impl<'a, K, V> CursorMut<'a, K, V> {
    fn next(&mut self) -> Option<(&K, &mut V)>;
    fn prev(&mut self) -> Option<(&K, &mut V)>;
    fn peek_next(&mut self) -> Option<(&K, &mut V)>;
    fn peek_prev(&mut self) -> Option<(&K, &mut V)>;

    unsafe fn insert_after_unchecked(&mut self, key: K, value: V);
    unsafe fn insert_before_unchecked(&mut self, key: K, value: V);
    fn insert_after(&mut self, key: K, value: V) -> Result<(), UnorderedKeyError>;
    fn insert_before(&mut self, key: K, value: V) -> Result<(), UnorderedKeyError>;
    fn remove_next(&mut self) -> Option<(K, V)>;
    fn remove_prev(&mut self) -> Option<(K, V)>;

    fn as_cursor(&self) -> Cursor<'_, K, V>;

    unsafe fn with_mutable_key(self) -> CursorMutKey<'a, K, V, A>;
}

struct CursorMutKey<'a, K: 'a, V: 'a>;

impl<'a, K, V> CursorMut<'a, K, V> {
    fn next(&mut self) -> Option<(&mut K, &mut V)>;
    fn prev(&mut self) -> Option<(&mut K, &mut V)>;
    fn peek_next(&mut self) -> Option<(&mut K, &mut V)>;
    fn peek_prev(&mut self) -> Option<(&mut K, &mut V)>;

    unsafe fn insert_after_unchecked(&mut self, key: K, value: V);
    unsafe fn insert_before_unchecked(&mut self, key: K, value: V);
    fn insert_after(&mut self, key: K, value: V) -> Result<(), UnorderedKeyError>;
    fn insert_before(&mut self, key: K, value: V) -> Result<(), UnorderedKeyError>;
    fn remove_next(&mut self) -> Option<(K, V)>;
    fn remove_prev(&mut self) -> Option<(K, V)>;

    fn as_cursor(&self) -> Cursor<'_, K, V>;

    unsafe fn with_mutable_key(self) -> CursorMutKey<'a, K, V, A>;
}

struct UnorderedKeyError;
```
2024-01-25 17:39:26 +01:00
Jake Goulding
5772818dc8 Adjust library tests for unused_tuple_struct_fields -> dead_code 2024-01-02 15:34:37 -05:00
Kent Ross
f2e711e4c2 fix minor mistake in comments describing VecDeque resizing 2023-12-21 15:20:14 -08:00
surechen
40ae34194c remove redundant imports
detects redundant imports that can be eliminated.

for #117772 :

In order to facilitate review and modification, split the checking code and
removing redundant imports code into two PR.
2023-12-10 10:56:22 +08:00
bors
1a3aa4ad14 Auto merge of #114136 - TennyZhuang:linked-list-retain, r=thomcc
add LinkedList::{retain,retain_mut}

Implement #114135

The API is consistent with other collections.
2023-12-09 02:38:45 +00:00
Matthias Krüger
b7016ae205
Rollup merge of #118398 - mu001999:std/add_cfgs, r=thomcc
Add proper cfgs in std

Detected by #118257
2023-11-29 04:23:23 +01:00
bors
df0295f071 Auto merge of #110353 - the8472:in-place-flatten-chunks, r=cuviper
Expand in-place iteration specialization to Flatten, FlatMap and ArrayChunks

This enables the following cases to collect in-place:

```rust
let v = vec![[0u8; 4]; 1024]
let v: Vec<_> = v.into_iter().flatten().collect();

let v: Vec<Option<NonZeroUsize>> = vec![NonZeroUsize::new(0); 1024];
let v: Vec<_> = v.into_iter().flatten().collect();

let v = vec![u8; 4096];
let v: Vec<_> = v.into_iter().array_chunks::<4>().collect();
```

Especially the nicheful-option-flattening should be useful in real code.
2023-11-28 12:22:16 +00:00
r0cky
c751bfa015 Add proper cfgs 2023-11-28 09:02:34 +08:00
Amanieu d'Antras
d085f34a2d Add UnorderedKeyError 2023-11-23 16:05:29 +00:00
Amanieu d'Antras
166e348564
Update library/alloc/src/collections/btree/map.rs
Co-authored-by: Joe ST <joe@fbstj.net>
2023-11-23 12:37:20 +00:00
Amanieu d'Antras
8ee9693177 Rewrite the BTreeMap cursor API using gaps
Tracking issue: #107540

Currently, a `Cursor` points to a single element in the tree, and allows
moving to the next or previous element while mutating the tree. However
this was found to be confusing and hard to use.

This PR completely refactors cursors to instead point to a gap between
two elements in the tree. This eliminates the need for a "ghost" element
that exists after the last element and before the first one.
Additionally, `upper_bound` and `lower_bound` now have a much clearer
meaning.

The ability to mutate keys is also factored out into a separate
`CursorMutKey` type which is unsafe to create. This makes the API easier
to use since it avoids duplicated versions of each method with and
without key mutation.

API summary:

```rust
impl<K, V> BTreeMap<K, V> {
    fn lower_bound<Q>(&self, bound: Bound<&Q>) -> Cursor<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn lower_bound_mut<Q>(&mut self, bound: Bound<&Q>) -> CursorMut<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn upper_bound<Q>(&self, bound: Bound<&Q>) -> Cursor<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
    fn upper_bound_mut<Q>(&mut self, bound: Bound<&Q>) -> CursorMut<'_, K, V>
    where
        K: Borrow<Q> + Ord,
        Q: Ord;
}

struct Cursor<'a, K: 'a, V: 'a>;

impl<'a, K, V> Cursor<'a, K, V> {
    fn next(&mut self) -> Option<(&'a K, &'a V)>;
    fn prev(&mut self) -> Option<(&'a K, &'a V)>;
    fn peek_next(&self) -> Option<(&'a K, &'a V)>;
    fn peek_prev(&self) -> Option<(&'a K, &'a V)>;
}

struct CursorMut<'a, K: 'a, V: 'a>;

impl<'a, K, V> CursorMut<'a, K, V> {
    fn next(&mut self) -> Option<(&K, &mut V)>;
    fn prev(&mut self) -> Option<(&K, &mut V)>;
    fn peek_next(&mut self) -> Option<(&K, &mut V)>;
    fn peek_prev(&mut self) -> Option<(&K, &mut V)>;

    unsafe fn insert_after_unchecked(&mut self, key: K, value: V);
    unsafe fn insert_before_unchecked(&mut self, key: K, value: V);
    fn insert_after(&mut self, key: K, value: V);
    fn insert_before(&mut self, key: K, value: V);
    fn remove_next(&mut self) -> Option<(K, V)>;
    fn remove_prev(&mut self) -> Option<(K, V)>;

    fn as_cursor(&self) -> Cursor<'_, K, V>;

    unsafe fn with_mutable_key(self) -> CursorMutKey<'a, K, V, A>;
}

struct CursorMutKey<'a, K: 'a, V: 'a>;

impl<'a, K, V> CursorMut<'a, K, V> {
    fn next(&mut self) -> Option<(&mut K, &mut V)>;
    fn prev(&mut self) -> Option<(&mut K, &mut V)>;
    fn peek_next(&mut self) -> Option<(&mut K, &mut V)>;
    fn peek_prev(&mut self) -> Option<(&mut K, &mut V)>;

    unsafe fn insert_after_unchecked(&mut self, key: K, value: V);
    unsafe fn insert_before_unchecked(&mut self, key: K, value: V);
    fn insert_after(&mut self, key: K, value: V);
    fn insert_before(&mut self, key: K, value: V);
    fn remove_next(&mut self) -> Option<(K, V)>;
    fn remove_prev(&mut self) -> Option<(K, V)>;

    fn as_cursor(&self) -> Cursor<'_, K, V>;

    unsafe fn with_mutable_key(self) -> CursorMutKey<'a, K, V, A>;
}
```
2023-11-23 11:42:55 +00:00
coekjan
4dd7568a97
mark constructor of BinaryHeap as const fn 2023-10-28 21:30:43 +08:00
Sven Bartscher
d60b43c06a Make BTreeSet::new_in const 2023-10-09 11:17:56 +02:00
Sven Bartscher
bbc230478c Make BTreeMap::new_in const
Closes rust-lang/wg-allocators#118
2023-10-09 11:08:48 +02:00
cui fliter
f44d116e1f Fix misuses of a vs an
Signed-off-by: cui fliter <imcusg@gmail.com>
2023-10-04 08:01:11 +08:00
mxnkarou
1c7a77a638
edit std::collections::VecDeque docs 2023-09-16 15:52:34 +02:00
The 8472
3ca6bb0b44 Expand in-place iteration specialization to Flatten, FlatMap and ArrayChunks 2023-09-03 19:59:47 +02:00
Ryan Lowe
80277dd8f2 Avoid using ptr::Unique in LinkedList code 2023-07-30 11:21:24 -04:00
bors
4c9ac1e93b Auto merge of #114236 - fee1-dead-contrib:rollup-m92j7q1, r=fee1-dead
Rollup of 3 pull requests

Successful merges:

 - #112151 (Clarify behavior of inclusive bounds in BTreeMap::{lower,upper}_bound)
 - #113512 (Updated lines doc to include trailing carriage return note)
 - #114203 (Effects: don't print `host` param in diagnostics)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-07-30 07:57:13 +00:00
fee1-dead
3143030cda
Rollup merge of #112151 - chloekek:patch-1, r=workingjubilee
Clarify behavior of inclusive bounds in BTreeMap::{lower,upper}_bound

It wasn’t quite clear to me how these methods would interpret inclusive bounds so I added examples for those.
2023-07-30 07:13:01 +00:00
bors
2e0136a131 Auto merge of #112280 - zica87:master, r=workingjubilee
Remove redundant example of `BTreeSet::iter`

The usage and that `Values returned by the iterator are returned in ascending order` are already demonstrated by the other example and the description, so I removed the useless one.
2023-07-30 06:12:03 +00:00
Tshepang Mbambo
85779214c8
btree/map.rs: remove "Basic usage" text
Not useful, for there is just a single example
2023-07-28 14:24:56 +02:00
TennyZhuang
5df60f47e8 add LinkedList::{retain,retain_mut}
Signed-off-by: TennyZhuang <zty0826@gmail.com>
2023-07-28 00:28:19 +08:00
Pedro Lobo
30a029e51b
Fix VecDeque's rotate_left and rotate_right panic tests 2023-07-13 18:39:09 +01:00
Pedro Lobo
c0a105be7c
Rename VecDeque's rotate_left and rotate_right parameters 2023-07-13 18:10:52 +01:00
The 8472
114d5f221c s/drain_filter/extract_if/ for Vec, Btree{Map,Set} and LinkedList 2023-06-14 09:28:54 +02:00
The 8472
b7ce7edd87 remove drain-on-drop behavior from linked_list::DrainFilter and add #[must_use] 2023-06-14 09:24:51 +02:00
The 8472
b687e84aeb remove drain-on-drop behavior from BTree{Set,Map}::DrainFilter and add #[must_use] 2023-06-14 09:24:51 +02:00