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			42 lines
		
	
	
		
			989 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			42 lines
		
	
	
		
			989 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //@ compile-flags: -Cno-prepopulate-passes -Copt-level=0
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| 
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| #![crate_type = "lib"]
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| 
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| #[no_mangle]
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| pub fn demo_for_i32() {
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|     generic_impl::<i32>();
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| }
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| 
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| // Two important things here:
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| // - We replace the "then" block with `unreachable` to avoid linking problems
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| // - We neither declare nor define the `big_impl` that said block "calls".
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| 
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| // CHECK-LABEL: ; skip_mono_inside_if_false::generic_impl
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| // CHECK: start:
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| // CHECK-NEXT: br label %[[ELSE_BRANCH:bb[0-9]+]]
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| // CHECK: [[ELSE_BRANCH]]:
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| // CHECK-NEXT: call skip_mono_inside_if_false::small_impl
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| // CHECK: bb{{[0-9]+}}:
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| // CHECK-NEXT: ret void
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| // CHECK: bb{{[0-9+]}}:
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| // CHECK-NEXT: unreachable
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| 
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| fn generic_impl<T>() {
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|     trait MagicTrait {
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|         const IS_BIG: bool;
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|     }
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|     impl<T> MagicTrait for T {
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|         const IS_BIG: bool = std::mem::size_of::<T>() > 10;
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|     }
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|     if T::IS_BIG {
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|         big_impl::<T>();
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|     } else {
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|         small_impl::<T>();
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|     }
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| }
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| 
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| #[inline(never)]
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| fn small_impl<T>() {}
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| #[inline(never)]
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| fn big_impl<T>() {}
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