tests/codegen/issue-86106.rs

   1 // min-llvm-version: 15.0
   2 // compile-flags: -C opt-level=3 -Z merge-functions=disabled
   3
   4 // The below two functions ensure that both `String::new()` and `"".to_string()`
   5 // produce the identical code.
   6
   7 #![crate_type = "lib"]
   8
   9 // CHECK-LABEL: define void @string_new
  10 #[no_mangle]
  11 pub fn string_new() -> String {
  12     // CHECK-NOT: load i8
  13     // CHECK: store i{{32|64}}
  14     // CHECK-NEXT: getelementptr
  15     // CHECK-NEXT: store ptr
  16     // CHECK-NEXT: getelementptr
  17     // CHECK-NEXT: store i{{32|64}}
  18     // CHECK-NEXT: ret void
  19     String::new()
  20 }
  21
  22 // CHECK-LABEL: define void @empty_to_string
  23 #[no_mangle]
  24 pub fn empty_to_string() -> String {
  25     // CHECK-NOT: load i8
  26     // CHECK: store i{{32|64}}
  27     // CHECK-NEXT: getelementptr
  28     // CHECK-NEXT: store ptr
  29     // CHECK-NEXT: getelementptr
  30     // CHECK-NEXT: store i{{32|64}}
  31     // CHECK-NEXT: ret void
  32     "".to_string()
  33 }
  34
  35 // The below two functions ensure that both `vec![]` and `vec![].clone()`
  36 // produce the identical code.
  37
  38 // CHECK-LABEL: @empty_vec
  39 #[no_mangle]
  40 pub fn empty_vec() -> Vec<u8> {
  41     // CHECK: store i{{32|64}}
  42     // CHECK-NOT: load i8
  43     // CHECK-NEXT: getelementptr
  44     // CHECK-NEXT: store ptr
  45     // CHECK-NEXT: getelementptr
  46     // CHECK-NEXT: store i{{32|64}}
  47     // CHECK-NEXT: ret void
  48     vec![]
  49 }
  50
  51 // CHECK-LABEL: @empty_vec_clone
  52 #[no_mangle]
  53 pub fn empty_vec_clone() -> Vec<u8> {
  54     // CHECK: store i{{32|64}}
  55     // CHECK-NOT: load i8
  56     // CHECK-NEXT: getelementptr
  57     // CHECK-NEXT: store ptr
  58     // CHECK-NEXT: getelementptr
  59     // CHECK-NEXT: store i{{32|64}}
  60     // CHECK-NEXT: ret void
  61     vec![].clone()
  62 }