llvm/llvm/test/CodeGen/MIR/X86/successor-basic-blocks.mir

# RUN: llc -march=x86-64 -run-pass none -o - %s | FileCheck %s
# This test ensures that the MIR parser parses basic block successors correctly.

--- |

  define i32 @foo(i32 %a) {
  entry:
    %0 = icmp sle i32 %a, 10
    br i1 %0, label %less, label %exit

  less:
    ret i32 0

  exit:
    ret i32 %a
  }

  define i32 @bar(i32 %a) {
  entry:
    %b = icmp sle i32 %a, 10
    br i1 %b, label %0, label %1

  ; <label>:0
    ret i32 0

  ; <label>:1
    ret i32 %a
  }

...
---
name:            foo
body: |
  ; CHECK-LABEL: bb.0.entry:
  ; CHECK-LABEL: bb.1.less:
  bb.0.entry:
    successors: %bb.1.less, %bb.2.exit
    liveins: $edi

    CMP32ri8 $edi, 10, implicit-def $eflags
    JCC_1 %bb.2.exit, 15, implicit killed $eflags

  bb.1.less:
    $eax = MOV32r0 implicit-def dead $eflags
    RET64 killed $eax

  bb.2.exit:
    liveins: $edi

    $eax = COPY killed $edi
    RET64 killed $eax
...
---
name:            bar
body: |
  ; CHECK-LABEL: name: bar
  ; Verify that we can have multiple lists of successors that will be merged
  ; into one.
  ; CHECK-LABEL: bb.0.entry:
  ; CHECK:         successors: %bb.1(0x80000000), %bb.2(0x00000000)
  bb.0.entry:
    liveins: $edi
    successors: %bb.1
    successors: %bb.2

    CMP32ri8 $edi, 10, implicit-def $eflags
    JCC_1 %bb.2, 15, implicit killed $eflags

  ; Verify that we can have an empty list of successors.
  ; CHECK-LABEL: bb.1:
  ; CHECK-NEXT:  $eax = MOV32r0 implicit-def dead $eflags
  bb.1:
    successors:
    $eax = MOV32r0 implicit-def dead $eflags
    RET64 killed $eax

  bb.2:
    liveins: $edi

    $eax = COPY killed $edi
    RET64 killed $eax
...