Migrate intrinsic-unreachable test to asm!

Author: tmiasko

src/test/run-make-fulldeps/intrinsic-unreachable/exit-ret.rs

@@ -1,12 +1,11 @@
-#![feature(llvm_asm)]
 #![crate_type="lib"]
+use std::arch::asm;
 
 #[deny(unreachable_code)]
 pub fn exit(n: usize) -> i32 {
     unsafe {
         // Pretend this asm is an exit() syscall.
-        llvm_asm!("" :: "r"(n) :: "volatile");
-        // Can't actually reach this point, but rustc doesn't know that.
+        asm!("/*{0}*/", in(reg) n);
     }
     // This return value is just here to generate some extra code for a return
     // value, making it easier for the test script to detect whether the

src/test/run-make-fulldeps/intrinsic-unreachable/exit-unreachable.rs

@@ -1,13 +1,14 @@
-#![feature(llvm_asm, core_intrinsics)]
+#![feature(core_intrinsics)]
 #![crate_type="lib"]
+use std::arch::asm;
 
 use std::intrinsics;
 
 #[allow(unreachable_code)]
 pub fn exit(n: usize) -> i32 {
     unsafe {
         // Pretend this asm is an exit() syscall.
-        llvm_asm!("" :: "r"(n) :: "volatile");
+        asm!("/*{0}*/", in(reg) n);
         intrinsics::unreachable()
     }
     // This return value is just here to generate some extra code for a return