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Last active August 13, 2016 17:04
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#2: Should builder methods use `mut self` or `&mut self`?
mod builder {
#[derive(Default, Clone)]
pub struct Channel {
a: i32,
b: i32,
c: i32,
}
impl Channel {
pub fn a<VALUE: Into<i32>>(&mut self, value: VALUE) -> &mut Self {
self.a = value.into();
self
}
pub fn b<VALUE: Into<i32>>(&mut self, value: VALUE) -> &mut Self {
self.b = value.into();
self
}
pub fn c<VALUE: Into<i32>>(&mut self, value: VALUE) -> &mut Self {
self.c = value.into();
self
}
}
impl Channel {
pub fn build(&mut self) -> Self {
Channel {
a: self.a,
b: self.b,
c: self.c,
}
}
}
}
mod foo {
use super::builder::Channel;
pub fn a<VALUE: Into<i32>>(mut builder: Channel, value: VALUE) -> Channel {
builder.a(value.into()).clone()
}
pub fn b<VALUE: Into<i32>>(mut builder: Channel, value: VALUE) -> Channel {
builder.b(value.into()).clone()
}
pub fn c<VALUE: Into<i32>>(mut builder: Channel, value: VALUE) -> Channel {
builder.c(value.into()).clone()
}
}
/// consume variables with black_box to avoid optimization of trivial code.
#[inline(never)]
fn black_box(_x: builder::Channel) {
}
fn main() {
let mut builder = builder::Channel::default();
builder = foo::a(builder, 1);
builder = foo::b(builder, 2);
builder = foo::c(builder, 3);
let ch = builder.build();
black_box(ch);
}
; ModuleID = 'rust_out.0.rs'
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
%"builder::Channel" = type { i32, i32, i32 }
; Function Attrs: noinline norecurse nounwind uwtable
define internal fastcc void @_ZN8rust_out9black_box17h4fbb43c364fffe15E(%"builder::Channel"* noalias nocapture dereferenceable(12) %_x) unnamed_addr #0 {
entry-block:
%0 = bitcast %"builder::Channel"* %_x to i8*
tail call void @llvm.lifetime.end(i64 12, i8* %0)
ret void
}
; Function Attrs: argmemonly nounwind
declare void @llvm.lifetime.end(i64, i8* nocapture) #1
; Function Attrs: norecurse nounwind uwtable
define internal void @_ZN8rust_out4main17h4bd17b1d5c1469adE() unnamed_addr #2 {
entry-block:
%arg3 = alloca %"builder::Channel", align 8
%0 = bitcast %"builder::Channel"* %arg3 to i8*
call void @llvm.lifetime.start(i64 12, i8* %0)
%1 = getelementptr inbounds %"builder::Channel", %"builder::Channel"* %arg3, i64 0, i32 0
store i32 1, i32* %1, align 8
%2 = getelementptr inbounds %"builder::Channel", %"builder::Channel"* %arg3, i64 0, i32 1
store i32 2, i32* %2, align 4
%3 = getelementptr inbounds %"builder::Channel", %"builder::Channel"* %arg3, i64 0, i32 2
store i32 3, i32* %3, align 8
call fastcc void @_ZN8rust_out9black_box17h4fbb43c364fffe15E(%"builder::Channel"* noalias nocapture nonnull dereferenceable(12) %arg3)
call void @llvm.lifetime.end(i64 12, i8* %0)
ret void
}
; Function Attrs: argmemonly nounwind
declare void @llvm.lifetime.start(i64, i8* nocapture) #1
define i64 @main(i64, i8**) unnamed_addr {
top:
%2 = tail call i64 @_ZN3std2rt10lang_start17hbcefdc316c2fbd45E(i8* bitcast (void ()* @_ZN8rust_out4main17h4bd17b1d5c1469adE to i8*), i64 %0, i8** %1)
ret i64 %2
}
declare i64 @_ZN3std2rt10lang_start17hbcefdc316c2fbd45E(i8*, i64, i8**) unnamed_addr
attributes #0 = { noinline norecurse nounwind uwtable }
attributes #1 = { argmemonly nounwind }
attributes #2 = { norecurse nounwind uwtable }
.text
.file "aio.cgu-0.rs"
.section .text._ZN3aio4main17h1a1276b84a14ae38E,"ax",@progbits
.p2align 4, 0x90
.type _ZN3aio4main17h1a1276b84a14ae38E,@function
_ZN3aio4main17h1a1276b84a14ae38E:
.cfi_startproc
retq
.Lfunc_end0:
.size _ZN3aio4main17h1a1276b84a14ae38E, .Lfunc_end0-_ZN3aio4main17h1a1276b84a14ae38E
.cfi_endproc
.section .text.main,"ax",@progbits
.globl main
.p2align 4, 0x90
.type main,@function
main:
.cfi_startproc
movq %rsi, %rax
movq %rdi, %rcx
leaq _ZN3aio4main17h1a1276b84a14ae38E(%rip), %rdi
movq %rcx, %rsi
movq %rax, %rdx
jmp _ZN3std2rt10lang_start17hfe9ab243c60ffb9bE@PLT
.Lfunc_end1:
.size main, .Lfunc_end1-main
.cfi_endproc
.section ".note.GNU-stack","",@progbits
.text
.file "rust_out.0.rs"
.section .text._ZN8rust_out9black_box17h4fbb43c364fffe15E,"ax",@progbits
.align 16, 0x90
.type _ZN8rust_out9black_box17h4fbb43c364fffe15E,@function
_ZN8rust_out9black_box17h4fbb43c364fffe15E:
.cfi_startproc
retq
.Lfunc_end0:
.size _ZN8rust_out9black_box17h4fbb43c364fffe15E, .Lfunc_end0-_ZN8rust_out9black_box17h4fbb43c364fffe15E
.cfi_endproc
.section .text._ZN8rust_out4main17h4bd17b1d5c1469adE,"ax",@progbits
.align 16, 0x90
.type _ZN8rust_out4main17h4bd17b1d5c1469adE,@function
_ZN8rust_out4main17h4bd17b1d5c1469adE:
.cfi_startproc
subq $24, %rsp
.Ltmp0:
.cfi_def_cfa_offset 32
movabsq $8589934593, %rax
movq %rax, 8(%rsp)
movl $3, 16(%rsp)
leaq 8(%rsp), %rdi
callq _ZN8rust_out9black_box17h4fbb43c364fffe15E
addq $24, %rsp
retq
.Lfunc_end1:
.size _ZN8rust_out4main17h4bd17b1d5c1469adE, .Lfunc_end1-_ZN8rust_out4main17h4bd17b1d5c1469adE
.cfi_endproc
.section .text.main,"ax",@progbits
.globl main
.align 16, 0x90
.type main,@function
main:
.cfi_startproc
movq %rsi, %rax
movq %rdi, %rcx
leaq _ZN8rust_out4main17h4bd17b1d5c1469adE(%rip), %rdi
movq %rcx, %rsi
movq %rax, %rdx
jmp _ZN3std2rt10lang_start17hbcefdc316c2fbd45E@PLT
.Lfunc_end2:
.size main, .Lfunc_end2-main
.cfi_endproc
.section ".note.GNU-stack","",@progbits
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