tests/assembly/target-feature-multiple.rs

   1 // assembly-output: emit-asm
   2 // needs-llvm-components: x86
   3 // revisions: TWOFLAGS SINGLEFLAG
   4 // compile-flags: --target=x86_64-unknown-linux-gnu
   5 // [TWOFLAGS] compile-flags: -C target-feature=+rdrnd -C target-feature=+rdseed
   6 // [SINGLEFLAG] compile-flags: -C target-feature=+rdrnd,+rdseed
   7
   8 // Target features set via flags aren't necessarily reflected in the IR, so the only way to test
   9 // them is to build code that requires the features to be enabled to work.
  10 //
  11 // In this particular test if `rdrnd,rdseed` somehow didn't make it to LLVM, the instruction
  12 // selection should crash.
  13 //
  14 // > LLVM ERROR: Cannot select: 0x7f00f400c010: i32,i32,ch = X86ISD::RDSEED 0x7f00f400bfa8:2
  15 // > In function: foo
  16 //
  17 // See also tests/codegen/target-feature-overrides.rs
  18 #![feature(no_core, lang_items, link_llvm_intrinsics, abi_unadjusted)]
  19 #![crate_type = "lib"]
  20 #![no_core]
  21
  22 #[lang = "sized"]
  23 trait Sized {}
  24 #[lang = "copy"]
  25 trait Copy {}
  26 impl Copy for u32 {}
  27
  28 // Use of these requires target features to be enabled
  29 extern "unadjusted" {
  30     #[link_name = "llvm.x86.rdrand.32"]
  31     fn x86_rdrand32_step() -> (u32, i32);
  32     #[link_name = "llvm.x86.rdseed.32"]
  33     fn x86_rdseed32_step() -> (u32, i32);
  34 }
  35
  36 #[no_mangle]
  37 pub unsafe fn foo() -> (u32, u32) {
  38     // CHECK-LABEL: foo:
  39     // CHECK: rdrand
  40     // CHECK: rdseed
  41     (x86_rdrand32_step().0, x86_rdseed32_step().0)
  42 }