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			37 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // LLVM does not support some atomic RMW operations on pointers, so inside codegen we lower those
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| // to integer atomics, surrounded by casts to and from integer type.
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| // This test ensures that we do the round-trip correctly for AtomicPtr::fetch_byte_add, and also
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| // ensures that we do not have such a round-trip for AtomicPtr::swap, because LLVM supports pointer
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| // arguments to `atomicrmw xchg`.
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| 
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| //@ compile-flags: -Copt-level=3 -Cno-prepopulate-passes
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| #![crate_type = "lib"]
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| #![feature(strict_provenance_atomic_ptr)]
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| 
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| use std::ptr::without_provenance_mut;
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| use std::sync::atomic::AtomicPtr;
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| use std::sync::atomic::Ordering::Relaxed;
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| 
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| // Portability hack so that we can say [[USIZE]] instead of i64/i32/i16 for usize.
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| // CHECK: @helper([[USIZE:i[0-9]+]] noundef %_1)
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| #[no_mangle]
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| pub fn helper(_: usize) {}
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| 
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| // CHECK-LABEL: @atomicptr_fetch_byte_add
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| #[no_mangle]
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| pub fn atomicptr_fetch_byte_add(a: &AtomicPtr<u8>, v: usize) -> *mut u8 {
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|     // CHECK: %[[INTPTR:.*]] = ptrtoint ptr %{{.*}} to [[USIZE]]
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|     // CHECK-NEXT: %[[RET:.*]] = atomicrmw add ptr %{{.*}}, [[USIZE]] %[[INTPTR]]
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|     // CHECK-NEXT: inttoptr [[USIZE]] %[[RET]] to ptr
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|     a.fetch_byte_add(v, Relaxed)
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| }
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| 
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| // CHECK-LABEL: @atomicptr_swap
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| #[no_mangle]
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| pub fn atomicptr_swap(a: &AtomicPtr<u8>, ptr: *mut u8) -> *mut u8 {
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|     // CHECK-NOT: ptrtoint
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|     // CHECK: atomicrmw xchg ptr %{{.*}}, ptr %{{.*}} monotonic
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|     // CHECK-NOT: inttoptr
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|     a.swap(ptr, Relaxed)
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| }
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