win64-eh-empty-block-2.mir 7.32 KB
# RUN: llc -start-before=x86-avoid-trailing-call %s -o - | FileCheck %s

# If there is a trailing unreachable block, make sure it is non-empty.

# Manually modified the IR of the following C++ to share one unreachable block,
# as clang does for the real C++ throw:
# void __declspec(noreturn) mythrow();
# int multi_throw(bool c1, bool c2, bool c3) {
#   try {
#     if (c1)
#       mythrow();
#     if (c2)
#       mythrow();
#     if (c3)
#       mythrow();
#   } catch (...) {
#     return 1;
#   }
#   return 0;
# }

# CHECK-LABEL: "?multi_throw@@YAH_N00@Z": # @"?multi_throw@@YAH_N00@Z"
# CHECK: retq
# CHECK: .LBB{{.*}} # %if.then
# CHECK: callq mythrow
# CHECK: .LBB{{.*}} # %if.then4
# CHECK: callq mythrow
# CHECK: .LBB{{.*}} # %if.then8
# CHECK: callq mythrow
# CHECK: .LBB{{.*}} # %unreachable
# CHECK-NEXT: int3
# CHECK: .seh_endproc
# CHECK: # %catch

--- |
  ; ModuleID = '../llvm/test/CodeGen/X86/win64-eh-empty-block-2.ll'
  source_filename = "t.cpp"
  target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-windows-msvc19.11.0"

  ; Function Attrs: uwtable
  define dso_local i32 @"?multi_throw@@YAH_N00@Z"(i1 zeroext %c1, i1 zeroext %c2, i1 zeroext %c3) local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*) {
  entry:
    br i1 %c1, label %if.then, label %if.end

  if.then:                                          ; preds = %entry
    invoke void @mythrow()
            to label %unreachable unwind label %catch.dispatch

  unreachable:                                      ; preds = %if.then8, %if.then4, %if.then
    unreachable

  if.end:                                           ; preds = %entry
    br i1 %c2, label %if.then4, label %if.end6

  if.then4:                                         ; preds = %if.end
    invoke void @mythrow()
            to label %unreachable unwind label %catch.dispatch

  if.end6:                                          ; preds = %if.end
    br i1 %c3, label %if.then8, label %return

  if.then8:                                         ; preds = %if.end6
    invoke void @mythrow()
            to label %unreachable unwind label %catch.dispatch

  catch.dispatch:                                   ; preds = %if.then8, %if.then4, %if.then
    %0 = catchswitch within none [label %catch] unwind to caller

  catch:                                            ; preds = %catch.dispatch
    %1 = catchpad within %0 [i8* null, i32 64, i8* null]
    catchret from %1 to label %return

  return:                                           ; preds = %catch, %if.end6
    %retval.0 = phi i32 [ 1, %catch ], [ 0, %if.end6 ]
    ret i32 %retval.0
  }

  declare dso_local void @mythrow()

  declare dso_local i32 @__CxxFrameHandler3(...)

  attributes #0 = { uwtable }

  !llvm.module.flags = !{!0, !1}

  !0 = !{i32 1, !"wchar_size", i32 2}
  !1 = !{i32 7, !"PIC Level", i32 2}

...
---
name:            '?multi_throw@@YAH_N00@Z'
alignment:       16
exposesReturnsTwice: false
legalized:       false
regBankSelected: false
selected:        false
failedISel:      false
tracksRegLiveness: true
hasWinCFI:       true
registers:       []
liveins:
  - { reg: '$cl', virtual-reg: '' }
  - { reg: '$dl', virtual-reg: '' }
  - { reg: '$r8b', virtual-reg: '' }
frameInfo:
  isFrameAddressTaken: false
  isReturnAddressTaken: false
  hasStackMap:     false
  hasPatchPoint:   false
  stackSize:       56
  offsetAdjustment: -56
  maxAlignment:    8
  adjustsStack:    true
  hasCalls:        true
  stackProtector:  ''
  maxCallFrameSize: 32
  cvBytesOfCalleeSavedRegisters: 0
  hasOpaqueSPAdjustment: true
  hasVAStart:      false
  hasMustTailInVarArgFunc: false
  localFrameSize:  0
  savePoint:       ''
  restorePoint:    ''
fixedStack:
  - { id: 0, type: default, offset: -24, size: 8, alignment: 8, stack-id: default,
      isImmutable: false, isAliased: false, callee-saved-register: '',
      callee-saved-restored: true, debug-info-variable: '', debug-info-expression: '',
      debug-info-location: '' }
  - { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
      callee-saved-register: '', callee-saved-restored: true, debug-info-variable: '',
      debug-info-expression: '', debug-info-location: '' }
stack:
  - { id: 0, name: '', type: spill-slot, offset: -28, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
callSites:       []
constants:       []
machineFunctionInfo: {}
body:             |
  bb.0.entry:
    successors: %bb.1(0x00000001), %bb.3(0x7fffffff)
    liveins: $cl, $dl, $r8b

    frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
    frame-setup SEH_PushReg 50
    $rsp = frame-setup SUB64ri8 $rsp, 48, implicit-def dead $eflags
    frame-setup SEH_StackAlloc 48
    $rbp = LEA64r $rsp, 1, $noreg, 48, $noreg
    frame-setup SEH_SetFrame 50, 48
    frame-setup SEH_EndPrologue
    MOV64mi32 $rbp, 1, $noreg, -8, $noreg, -2 :: (store 8 into %fixed-stack.0)
    TEST8rr killed renamable $cl, renamable $cl, implicit-def $eflags
    JCC_1 %bb.1, 5, implicit $eflags

  bb.3.if.end:
    successors: %bb.4(0x00000001), %bb.5(0x7fffffff)
    liveins: $dl, $r8b

    TEST8rr killed renamable $dl, renamable $dl, implicit-def $eflags
    JCC_1 %bb.4, 5, implicit $eflags

  bb.5.if.end6:
    successors: %bb.6(0x00000001), %bb.8(0x7fffffff)
    liveins: $r8b

    MOV32mi $rbp, 1, $noreg, -12, $noreg, 0 :: (store 4 into %stack.0)
    TEST8rr killed renamable $r8b, renamable $r8b, implicit-def $eflags
    JCC_1 %bb.6, 5, implicit $eflags

  bb.8.return (address-taken):
    $eax = MOV32rm $rbp, 1, $noreg, -12, $noreg :: (load 4 from %stack.0)
    SEH_Epilogue
    $rsp = frame-destroy ADD64ri8 $rsp, 48, implicit-def dead $eflags
    $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp
    RETQ $eax

  bb.1.if.then:
    successors: %bb.2(0x7ffff800), %bb.7(0x00000800)

    EH_LABEL <mcsymbol .Leh1>
    CALL64pcrel32 @mythrow, csr_win64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp
    EH_LABEL <mcsymbol .Leh2>
    JMP_1 %bb.2

  bb.4.if.then4:
    successors: %bb.2(0x7ffff800), %bb.7(0x00000800)

    EH_LABEL <mcsymbol .Leh3>
    CALL64pcrel32 @mythrow, csr_win64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp
    EH_LABEL <mcsymbol .Leh4>
    JMP_1 %bb.2

  bb.6.if.then8:
    successors: %bb.2(0x7ffff800), %bb.7(0x00000800)

    EH_LABEL <mcsymbol .Leh5>
    CALL64pcrel32 @mythrow, csr_win64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp
    EH_LABEL <mcsymbol .Leh6>

  bb.2.unreachable:
    successors:


  bb.7.catch (landing-pad, ehfunclet-entry):
    successors: %bb.8(0x80000000)
    liveins: $rdx

    frame-setup MOV64mr killed $rsp, 1, $noreg, 16, $noreg, $rdx
    frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
    frame-setup SEH_PushReg 50
    $rsp = frame-setup SUB64ri8 $rsp, 32, implicit-def dead $eflags
    frame-setup SEH_StackAlloc 32
    $rbp = LEA64r $rdx, 1, $noreg, 48, $noreg
    frame-setup SEH_EndPrologue
    MOV32mi $rbp, 1, $noreg, -12, $noreg, 1 :: (store 4 into %stack.0)
    $rax = LEA64r $rip, 0, $noreg, %bb.8, $noreg
    SEH_Epilogue
    $rsp = frame-destroy ADD64ri8 $rsp, 32, implicit-def dead $eflags
    $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp
    CATCHRET %bb.8, %bb.0

...