test/Transforms/DeadStoreElimination/multiblock-unreachable.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=dse -S %s | FileCheck %s

target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"

; Make sure we do not crash when we encounter unreachable blocks while checking
; if all paths to DomAccess go through a killing block.
define void @test(ptr %ptr, i1 %c.1, i1 %c.2, i1 %c.3) {
; CHECK-LABEL: @test(
; CHECK-NEXT:  bb:
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[BB27:%.*]], label [[BB53:%.*]]
; CHECK:       bb10:
; CHECK-NEXT:    br label [[BB43:%.*]]
; CHECK:       bb22:
; CHECK-NEXT:    br i1 [[C_2:%.*]], label [[BB22:%.*]], label [[BB53]]
; CHECK:       bb27:
; CHECK-NEXT:    br i1 [[C_3:%.*]], label [[BB38:%.*]], label [[BB39:%.*]]
; CHECK:       bb38:
; CHECK-NEXT:    store float 0.000000e+00, ptr [[PTR:%.*]], align 4
; CHECK-NEXT:    br label [[BB38]]
; CHECK:       bb39:
; CHECK-NEXT:    br i1 [[C_2]], label [[BB43]], label [[BB38]]
; CHECK:       bb43:
; CHECK-NEXT:    store float 0.000000e+00, ptr [[PTR]], align 4
; CHECK-NEXT:    br label [[BB50:%.*]]
; CHECK:       bb50:
; CHECK-NEXT:    br i1 [[C_3]], label [[BB27]], label [[BB53]]
; CHECK:       bb53:
; CHECK-NEXT:    br label [[BB53]]
;
bb:
  br i1 %c.1, label %bb27, label %bb53

bb10:                                             ; No predecessors!
  br label %bb43

bb22:                                             ; preds = %bb22
  br i1 %c.2, label %bb22, label %bb53

bb27:                                             ; preds = %bb50, %bb
  br i1 %c.3, label %bb38, label %bb39

bb38:                                             ; preds = %bb39, %bb38, %bb27
  store float 0.000000e+00, ptr %ptr, align 4
  br label %bb38

bb39:                                             ; preds = %bb27
  br i1 %c.2, label %bb43, label %bb38

bb43:                                             ; preds = %bb39, %bb10
  store float 0.000000e+00, ptr %ptr, align 4
  br label %bb50

bb50:                                             ; preds = %bb43
  br i1 %c.3, label %bb27, label %bb53

bb53:                                             ; preds = %bb53, %bb50, %bb22, %bb
  br label %bb53
}

declare void @exit()

define void @unreachable_exit_with_no_call(ptr noalias %ptr, i1 %c.1) {
; CHECK-LABEL: @unreachable_exit_with_no_call(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    unreachable
; CHECK:       if.end:
; CHECK-NEXT:    store i64 0, ptr [[PTR:%.*]], align 8
; CHECK-NEXT:    ret void
;
entry:
  store i64 1, ptr %ptr, align 8
  br i1 %c.1, label %if.then, label %if.end

if.then:
  unreachable

if.end:
  store i64 0, ptr %ptr, align 8
  ret void
}

; Test for PR53800.
define void @unreachable_exit_with_nounwind_call_pr53800(ptr noalias %ptr, i1 %c.1) {
; CHECK-LABEL: @unreachable_exit_with_nounwind_call_pr53800(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    tail call void @exit() #[[ATTR0:[0-9]+]]
; CHECK-NEXT:    unreachable
; CHECK:       if.end:
; CHECK-NEXT:    store i64 0, ptr [[PTR:%.*]], align 8
; CHECK-NEXT:    ret void
;
entry:
  store i64 1, ptr %ptr, align 8
  br i1 %c.1, label %if.then, label %if.end

if.then:
  tail call void @exit() nounwind
  unreachable

if.end:
  store i64 0, ptr %ptr, align 8
  ret void
}

; The call @exit may read %ptr as it is not marked as noalias
define void @unreachable_exit_and_call_may_read(ptr %ptr, i1 %c.1) {
; CHECK-LABEL: @unreachable_exit_and_call_may_read(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    store i64 1, ptr [[PTR:%.*]], align 8
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    tail call void @exit() #[[ATTR0]]
; CHECK-NEXT:    unreachable
; CHECK:       if.end:
; CHECK-NEXT:    store i64 0, ptr [[PTR]], align 8
; CHECK-NEXT:    ret void
;
entry:
  store i64 1, ptr %ptr, align 8
  br i1 %c.1, label %if.then, label %if.end

if.then:
  tail call void @exit() nounwind
  unreachable

if.end:
  store i64 0, ptr %ptr, align 8
  ret void
}

define void @unreachable_exit_with_may_unwind_call(ptr noalias %ptr, i1 %c.1) {
; CHECK-LABEL: @unreachable_exit_with_may_unwind_call(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    store i64 1, ptr [[PTR:%.*]], align 8
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    tail call void @exit()
; CHECK-NEXT:    unreachable
; CHECK:       if.end:
; CHECK-NEXT:    store i64 0, ptr [[PTR]], align 8
; CHECK-NEXT:    ret void
;
entry:
  store i64 1, ptr %ptr, align 8
  br i1 %c.1, label %if.then, label %if.end

if.then:
  tail call void @exit()
  unreachable

if.end:
  store i64 0, ptr %ptr, align 8
  ret void
}

; Cannot remove the store in entry, because it is not dead on the path to e.1
define void @unreachable_exit_but_another_exit(ptr noalias %ptr, i1 %c.1, i32 %s, i1 %c.2) {
; CHECK-LABEL: @unreachable_exit_but_another_exit(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    store i64 1, ptr [[PTR:%.*]], align 8
; CHECK-NEXT:    br i1 [[C_1:%.*]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    br i1 [[C_2:%.*]], label [[E_0:%.*]], label [[E_1:%.*]]
; CHECK:       e.0:
; CHECK-NEXT:    tail call void @exit() #[[ATTR0]]
; CHECK-NEXT:    unreachable
; CHECK:       e.1:
; CHECK-NEXT:    ret void
; CHECK:       if.end:
; CHECK-NEXT:    store i64 0, ptr [[PTR]], align 8
; CHECK-NEXT:    ret void
;
entry:
  store i64 1, ptr %ptr, align 8
  br i1 %c.1, label %if.then, label %if.end

if.then:
  br i1 %c.2, label %e.0, label %e.1

e.0:
  tail call void @exit() nounwind
  unreachable

e.1:
  ret void

if.end:
  store i64 0, ptr %ptr, align 8
  ret void
}