test/CodeGen/X86/block-placement.mir

# RUN: llc -mtriple=x86_64-apple-macosx10.12.0 -O3 -run-pass=block-placement -o - %s | FileCheck %s

--- |
  ; ModuleID = 'test.ll'
  source_filename = "test.ll"
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  
  declare void @stub(i32*)
  
  define i32 @f(i32* %ptr, i1 %cond) {
  entry:
    br i1 %cond, label %left, label %right
  
  left:                                             ; preds = %entry
    %is_null = icmp eq i32* %ptr, null
    br i1 %is_null, label %null, label %not_null, !prof !0, !make.implicit !1
  
  not_null:                                         ; preds = %left
    %val = load i32, i32* %ptr
    ret i32 %val
  
  null:                                             ; preds = %left
    call void @stub(i32* %ptr)
    unreachable
  
  right:                                            ; preds = %entry
    call void @stub(i32* null)
    unreachable
  }
  
  ; Function Attrs: nounwind
  declare void @llvm.stackprotector(i8*, i8**) #0
  
  attributes #0 = { nounwind }
  
  !0 = !{!"branch_weights", i32 1048575, i32 1}
  !1 = !{}

...
---
# CHECK: name:            f
name:            f
alignment:       4
tracksRegLiveness: true
liveins:         
  - { reg: '%rdi' }
  - { reg: '%esi' }

# CHECK: %eax = FAULTING_LOAD_OP %bb.3.null, 1684, killed %rdi, 1, _, 0, _ :: (load 4 from %ir.ptr)
# CHECK-NEXT: JMP_1 %bb.2.not_null
# CHECK: bb.3.null:
# CHECK:  bb.4.right:
# CHECK:  bb.2.not_null:

body:             |
  bb.0.entry:
    successors: %bb.1.left(0x7ffff800), %bb.3.right(0x00000800)
    liveins: %esi, %rdi
  
    frame-setup PUSH64r undef %rax, implicit-def %rsp, implicit %rsp
    CFI_INSTRUCTION def_cfa_offset 16
    TEST8ri %sil, 1, implicit-def %eflags, implicit killed %esi
    JE_1 %bb.3.right, implicit killed %eflags
  
  bb.1.left:
    successors: %bb.2.null(0x7ffff800), %bb.4.not_null(0x00000800)
    liveins: %rdi
  
    %eax = FAULTING_LOAD_OP %bb.2.null, 1684, killed %rdi, 1, _, 0, _ :: (load 4 from %ir.ptr)
    JMP_1 %bb.4.not_null
  
  bb.4.not_null:
    liveins: %rdi, %eax
  
    %rcx = POP64r implicit-def %rsp, implicit %rsp
    RETQ %eax

  bb.2.null:
    liveins: %rdi
  
    CALL64pcrel32 @stub, csr_64, implicit %rsp, implicit %rdi, implicit-def %rsp
  
  bb.3.right:
    dead %edi = XOR32rr undef %edi, undef %edi, implicit-def dead %eflags, implicit-def %rdi
    CALL64pcrel32 @stub, csr_64, implicit %rsp, implicit %rdi, implicit-def %rsp
  
...