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			37 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //@ compile-flags: -C opt-level=1
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| //@ only-64bit (because we're using [ui]size)
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| 
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| #![crate_type = "lib"]
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| #![feature(core_intrinsics)]
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| 
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| //! Basic optimizations are enabled because otherwise `x86_64-gnu-nopt` had an alloca.
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| //! Uses a type with non-power-of-two size to avoid normalizations to shifts.
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| 
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| use std::intrinsics::*;
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| 
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| type RGB = [u8; 3];
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| 
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| // CHECK-LABEL: @offset_from_odd_size
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| #[no_mangle]
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| pub unsafe fn offset_from_odd_size(a: *const RGB, b: *const RGB) -> isize {
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|     // CHECK: start
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|     // CHECK-NEXT: ptrtoint
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|     // CHECK-NEXT: ptrtoint
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|     // CHECK-NEXT: sub i64
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|     // CHECK-NEXT: sdiv exact i64 %{{[0-9]+}}, 3
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|     // CHECK-NEXT: ret i64
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|     ptr_offset_from(a, b)
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| }
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| 
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| // CHECK-LABEL: @offset_from_unsigned_odd_size
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| #[no_mangle]
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| pub unsafe fn offset_from_unsigned_odd_size(a: *const RGB, b: *const RGB) -> usize {
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|     // CHECK: start
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|     // CHECK-NEXT: ptrtoint
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|     // CHECK-NEXT: ptrtoint
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|     // CHECK-NEXT: sub nuw i64
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|     // CHECK-NEXT: udiv exact i64 %{{[0-9]+}}, 3
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|     // CHECK-NEXT: ret i64
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|     ptr_offset_from_unsigned(a, b)
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| }
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