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Add codegen test for array comparision opt #82459

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Add codegen test for array comparision opt #82459

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Add codegen test for array comparision opt
tesuji Feb 24, 2021
6490aeb
Update src/test/assembly/62531-array-cmp.rs
tesuji Feb 26, 2021
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21 changes: 21 additions & 0 deletions src/test/assembly/62531-array-cmp.rs
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// Ensure the asm for array comparisons is properly optimized on x86.

// min-llvm-version: 11
// assembly-output: emit-asm
// compile-flags: -C opt-level=2
// only-x86_64

#![crate_type = "lib"]

// CHECK-LABEL: compare
// CHECK: movb $1, %al
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Probably should CHECK-NEXT here. There are a number of plausible ways to generate code for this that would result in these two instructions somewhere, but not necessarily in just these two instructions.

// CHECK-NEXT: retq
#[no_mangle]
pub fn compare() -> bool {
let bytes = 12.5f32.to_ne_bytes();
bytes == if cfg!(target_endian = "big") {
[0x41, 0x48, 0x00, 0x00]
} else {
[0x00, 0x00, 0x48, 0x41]
}
}