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41 lines
1.1 KiB
Rust
41 lines
1.1 KiB
Rust
// compile-flags: -O
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#![crate_type = "lib"]
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#![feature(get_mut_unchecked, new_uninit)]
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use std::sync::Arc;
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// CHECK-LABEL: @new_from_array
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#[no_mangle]
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pub fn new_from_array(x: u64) -> Arc<[u64]> {
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// Ensure that we only generate one alloca for the array.
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// CHECK: alloca
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// CHECK-SAME: [1000 x i64]
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// CHECK-NOT: alloca
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let array = [x; 1000];
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Arc::new(array)
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}
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// CHECK-LABEL: @new_uninit
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#[no_mangle]
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pub fn new_uninit(x: u64) -> Arc<[u64; 1000]> {
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// CHECK: call alloc::sync::arcinner_layout_for_value_layout
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// CHECK-NOT: call alloc::sync::arcinner_layout_for_value_layout
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let mut arc = Arc::new_uninit();
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unsafe { Arc::get_mut_unchecked(&mut arc) }.write([x; 1000]);
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unsafe { arc.assume_init() }
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}
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// CHECK-LABEL: @new_uninit_slice
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#[no_mangle]
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pub fn new_uninit_slice(x: u64) -> Arc<[u64]> {
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// CHECK: call alloc::sync::arcinner_layout_for_value_layout
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// CHECK-NOT: call alloc::sync::arcinner_layout_for_value_layout
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let mut arc = Arc::new_uninit_slice(1000);
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for elem in unsafe { Arc::get_mut_unchecked(&mut arc) } {
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elem.write(x);
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}
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unsafe { arc.assume_init() }
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}
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