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			105 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // compile-flags: -O
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| // only-x86_64
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| 
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| #![crate_type = "rlib"]
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| 
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| use std::arch::asm;
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| 
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| // CHECK-LABEL: @pure
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| // CHECK-NOT: asm
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| // CHECK: ret void
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| #[no_mangle]
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| pub unsafe fn pure(x: i32) {
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|     let y: i32;
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|     asm!("", out("ax") y, in("cx") x, options(pure, nomem));
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| }
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| 
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| // CHECK-LABEL: @noreturn
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| // CHECK: call void asm
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| // CHECK-NEXT: unreachable
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| #[no_mangle]
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| pub unsafe fn noreturn() {
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|     asm!("", options(noreturn));
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| }
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| 
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| pub static mut VAR: i32 = 0;
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| pub static mut DUMMY_OUTPUT: i32 = 0;
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| 
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| // CHECK-LABEL: @readonly
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| // CHECK: call i32 asm
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| // CHECK: ret i32 1
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| #[no_mangle]
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| pub unsafe fn readonly() -> i32 {
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|     VAR = 1;
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|     asm!("", out("ax") DUMMY_OUTPUT, options(pure, readonly));
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|     VAR
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| }
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| 
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| // CHECK-LABEL: @not_readonly
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| // CHECK: call i32 asm
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| // CHECK: ret i32 %
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| #[no_mangle]
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| pub unsafe fn not_readonly() -> i32 {
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|     VAR = 1;
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|     asm!("", out("ax") DUMMY_OUTPUT, options());
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|     VAR
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| }
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| 
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| // CHECK-LABEL: @nomem
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| // CHECK-NOT: store
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| // CHECK: call i32 asm
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| // CHECK: store
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| // CHECK: ret i32 2
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| #[no_mangle]
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| pub unsafe fn nomem() -> i32 {
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|     VAR = 1;
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|     asm!("", out("ax") DUMMY_OUTPUT, options(pure, nomem));
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|     VAR = 2;
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|     VAR
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| }
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| 
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| // CHECK-LABEL: @nomem_nopure
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| // CHECK-NOT: store
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| // CHECK: call i32 asm
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| // CHECK: store
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| // CHECK: ret i32 2
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| #[no_mangle]
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| pub unsafe fn nomem_nopure() -> i32 {
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|     VAR = 1;
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|     asm!("", out("ax") DUMMY_OUTPUT, options(nomem));
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|     VAR = 2;
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|     VAR
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| }
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| 
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| // CHECK-LABEL: @not_nomem
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| // CHECK: store
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| // CHECK: call i32 asm
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| // CHECK: store
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| // CHECK: ret i32 2
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| #[no_mangle]
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| pub unsafe fn not_nomem() -> i32 {
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|     VAR = 1;
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|     asm!("", out("ax") DUMMY_OUTPUT, options(pure, readonly));
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|     VAR = 2;
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|     VAR
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| }
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| 
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| // CHECK-LABEL: @dont_remove_nonpure
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| // CHECK: call void asm
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| // CHECK: call void asm
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| // CHECK: call void asm
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| // CHECK: ret void
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| #[no_mangle]
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| pub unsafe fn dont_remove_nonpure() {
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|     asm!("", options());
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|     asm!("", options(nomem));
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|     asm!("", options(readonly));
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| }
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| 
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| // CHECK-LABEL: @raw
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| // CHECK: call void asm sideeffect inteldialect "{} {}", ""()
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| #[no_mangle]
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| pub unsafe fn raw() {
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|     asm!("{} {}", options(nostack, nomem, preserves_flags, raw));
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| }
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