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			20 lines
		
	
	
		
			510 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			20 lines
		
	
	
		
			510 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //@ compile-flags: -O
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| //@ min-llvm-version: 18
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| #![crate_type = "lib"]
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| 
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| use std::ptr::NonNull;
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| 
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| // CHECK-LABEL: @slice_ptr_len_1
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| // CHECK-NEXT: {{.*}}:
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| // CHECK-NEXT: ret {{i(32|64)}} %ptr.1
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| #[no_mangle]
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| pub fn slice_ptr_len_1(ptr: *const [u8]) -> usize {
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|     let ptr = ptr.cast_mut();
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|     if let Some(ptr) = NonNull::new(ptr) {
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|         ptr.len()
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|     } else {
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|         // We know ptr is null, so we know ptr.wrapping_byte_add(1) is not null.
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|         NonNull::new(ptr.wrapping_byte_add(1)).unwrap().len()
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|     }
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| }
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