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27 lines
754 B
Rust
27 lines
754 B
Rust
//@ compile-flags: -C opt-level=z
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//@ edition: 2021
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#![crate_type = "lib"]
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// From <https://github.com/rust-lang/rust/issues/115463>
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// CHECK-LABEL: @read_up_to_8(
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#[no_mangle]
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pub fn read_up_to_8(buf: &[u8]) -> u64 {
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// CHECK-NOT: unwrap_failed
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if buf.len() < 4 {
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// actual instance has more code.
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return 0;
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}
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let lo = u32::from_le_bytes(buf[..4].try_into().unwrap()) as u64;
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let hi = u32::from_le_bytes(buf[buf.len() - 4..][..4].try_into().unwrap()) as u64;
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lo | (hi << 8 * (buf.len() as u64 - 4))
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}
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// CHECK-LABEL: @checking_unwrap_expectation(
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#[no_mangle]
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pub fn checking_unwrap_expectation(buf: &[u8]) -> &[u8; 4] {
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// CHECK: call void @{{.*core6result13unwrap_failed}}
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buf.try_into().unwrap()
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}
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