test/CodeGen/AArch64/branch-relax-block-size.mir

# REQUIRES: asserts
# RUN: llc -mtriple=aarch64--linux-gnu -run-pass=branch-relaxation -debug-only=branch-relaxation %s -o /dev/null 2>&1 | FileCheck %s

# Ensure meta instructions (e.g. CFI_INSTRUCTION) don't contribute to the code
# size of a basic block.

# CHECK:  Basic blocks before relaxation
# CHECK-NEXT: %bb.0 offset=00000000 size=0x18
# CHECK-NEXT: %bb.1 offset=00000018 size=0x4
# CHECK-NEXT: %bb.2 offset=0000001c size=0xc

--- |
  target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
  target triple = "aarch64--linux-gnu"

  define i32 @test(i32* %a) #0 {
  entry:
    %call = tail call i32 @validate(i32* %a)
    %tobool = icmp eq i32 %call, 0
    br i1 %tobool, label %return, label %if.then

  if.then:                                          ; preds = %entry
    %0 = load i32, i32* %a, align 4
    br label %return

  return:                                           ; preds = %entry, %if.then
    %retval.0 = phi i32 [ %0, %if.then ], [ 0, %entry ]
    ret i32 %retval.0
  }

  declare i32 @validate(i32*)

  attributes #0 = { nounwind uwtable "disable-tail-calls"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" }

...
---
name:            test
alignment:       4
tracksRegLiveness: true
liveins:
  - { reg: '$x0' }
frameInfo:
  stackSize:       32
  maxAlignment:    16
  adjustsStack:    true
  hasCalls:        true
  maxCallFrameSize: 0
stack:
  - { id: 0, type: spill-slot, offset: -8, size: 8, alignment: 8, callee-saved-register: '$lr' }
  - { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 8, callee-saved-register: '$fp' }
  - { id: 2, type: spill-slot, offset: -32, size: 8, alignment: 16, callee-saved-register: '$x19' }
body:             |
  bb.0.entry:
    successors: %bb.2(0x30000000), %bb.1(0x50000000)
    liveins: $x0, $x19, $lr

    early-clobber $sp = frame-setup STRXpre killed $x19, $sp, -32 :: (store 8 into %stack.2)
    frame-setup STPXi $fp, killed $lr, $sp, 2 :: (store 8 into %stack.1), (store 8 into %stack.0)
    $fp = frame-setup ADDXri $sp, 16, 0
    frame-setup CFI_INSTRUCTION def_cfa $w29, 16
    frame-setup CFI_INSTRUCTION offset $w30, -8
    frame-setup CFI_INSTRUCTION offset $w29, -16
    frame-setup CFI_INSTRUCTION offset $w19, -32
    $x19 = ORRXrs $xzr, $x0, 0
    BL @validate, csr_aarch64_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $x0, implicit-def $sp, implicit-def $w0
    CBZW renamable $w0, %bb.2

  bb.1.if.then:
    liveins: $x19

    renamable $w0 = LDRWui killed renamable $x19, 0 :: (load 4 from %ir.a)

  bb.2.return:
    liveins: $w0

    $fp, $lr = frame-destroy LDPXi $sp, 2 :: (load 8 from %stack.1), (load 8 from %stack.0)
    early-clobber $sp, $x19 = frame-destroy LDRXpost $sp, 32 :: (load 8 from %stack.2)
    RET undef $lr, implicit killed $w0

...