test/CodeGen/MIR/X86/auto-successor.mir

# RUN: llc -mtriple=x86_64-- -o - %s -run-pass=none -verify-machineinstrs -simplify-mir | FileCheck %s
---
# We shouldn't need any explicit successor lists in these examples
# CHECK-LABEL: name: func0
# CHECK: bb.0:
# CHECK-NOT: successors
# CHECK: JE_1 %bb.1, implicit undef %eflags
# CHECK: JMP_1 %bb.3
# CHECK: bb.1:
# CHECK-NOT: successors
# CHECK: bb.2:
# CHECK-NOT: successors
# CHECK: JE_1 %bb.1, implicit undef %eflags
# CHECK: bb.3:
# CHECK: RETQ undef %eax
name: func0
body: |
  bb.0:
    JE_1 %bb.1, implicit undef %eflags
    JMP_1 %bb.3

  bb.1:

  bb.2:
    JE_1 %bb.1, implicit undef %eflags

  bb.3:
    JE_1 %bb.4, implicit undef %eflags   ; condjump+fallthrough to same block

  bb.4:
    RETQ undef %eax
...
---
# Some cases that need explicit successors:
# CHECK-LABEL: name: func1
name: func1
body: |
  bb.0:
    ; CHECK: bb.0:
    ; CHECK: successors: %bb.3, %bb.1
    successors: %bb.3, %bb.1   ; different order than operands
    JE_1 %bb.1, implicit undef %eflags
    JMP_1 %bb.3

  bb.1:
    ; CHECK: bb.1:
    ; CHECK: successors: %bb.2, %bb.1
    successors: %bb.2, %bb.1   ; different order (fallthrough variant)
    JE_1 %bb.1, implicit undef %eflags

  bb.2:
    ; CHECK: bb.2:
    ; CHECK: successors: %bb.1(0x60000000), %bb.3(0x20000000)
    successors: %bb.1(3), %bb.3(1)  ; branch probabilities not normalized
    JE_1 %bb.1, implicit undef %eflags

  bb.3:
    ; CHECK: bb.3:
    ; CHECK: RETQ undef %eax
    RETQ undef %eax
...