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			43 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			43 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
// assembly-output: emit-asm
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// needs-llvm-components: x86
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// revisions: TWOFLAGS SINGLEFLAG
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// compile-flags: --target=x86_64-unknown-linux-gnu
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// [TWOFLAGS] compile-flags: -C target-feature=+rdrnd -C target-feature=+rdseed
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// [SINGLEFLAG] compile-flags: -C target-feature=+rdrnd,+rdseed
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// Target features set via flags aren't necessarily reflected in the IR, so the only way to test
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// them is to build code that requires the features to be enabled to work.
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//
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// In this particular test if `rdrnd,rdseed` somehow didn't make it to LLVM, the instruction
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// selection should crash.
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//
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// > LLVM ERROR: Cannot select: 0x7f00f400c010: i32,i32,ch = X86ISD::RDSEED 0x7f00f400bfa8:2
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// > In function: foo
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//
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// See also tests/codegen/target-feature-overrides.rs
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#![feature(no_core, lang_items, link_llvm_intrinsics, abi_unadjusted)]
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#![crate_type = "lib"]
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#![no_core]
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#[lang = "sized"]
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trait Sized {}
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#[lang = "copy"]
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trait Copy {}
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impl Copy for u32 {}
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// Use of these requires target features to be enabled
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extern "unadjusted" {
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    #[link_name = "llvm.x86.rdrand.32"]
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    fn x86_rdrand32_step() -> (u32, i32);
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    #[link_name = "llvm.x86.rdseed.32"]
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    fn x86_rdseed32_step() -> (u32, i32);
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}
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#[no_mangle]
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pub unsafe fn foo() -> (u32, u32) {
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    // CHECK-LABEL: foo:
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    // CHECK: rdrand
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    // CHECK: rdseed
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    (x86_rdrand32_step().0, x86_rdseed32_step().0)
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}
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