; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
; RUN: opt -S -passes=gvn < %s | FileCheck %s

; Regression test for a GVN PRE assertion crash in PerformLoadPRE.

@b = external global [1 x i32]

define void @e() {
; CHECK-LABEL: define void @e() {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 true, label %[[FOR_END4:.*]], label %[[ENTRY_C_CRIT_EDGE:.*]]
; CHECK:       [[ENTRY_C_CRIT_EDGE]]:
; CHECK-NEXT:    [[DOTPRE1:%.*]] = load i32, ptr null, align 4
; CHECK-NEXT:    br label %[[C:.*]]
; CHECK:       [[FOR_END4]]:
; CHECK-NEXT:    store i32 0, ptr getelementptr inbounds nuw (i8, ptr @b, i64 4), align 4
; CHECK-NEXT:    [[DOTPRE:%.*]] = load i32, ptr null, align 4
; CHECK-NEXT:    br label %[[FOR_COND5:.*]]
; CHECK:       [[FOR_COND5]]:
; CHECK-NEXT:    [[TMP0:%.*]] = phi i32 [ [[TMP1:%.*]], %[[C]] ], [ [[DOTPRE]], %[[FOR_END4]] ]
; CHECK-NEXT:    [[CMP6:%.*]] = icmp eq i32 [[TMP0]], 0
; CHECK-NEXT:    br i1 [[CMP6]], label %[[FOR_COND5_C_CRIT_EDGE:.*]], label %[[FOR_END8:.*]]
; CHECK:       [[FOR_COND5_C_CRIT_EDGE]]:
; CHECK-NEXT:    [[DOTPRE2:%.*]] = load i32, ptr getelementptr inbounds nuw (i8, ptr @b, i64 4), align 4
; CHECK-NEXT:    br label %[[C]]
; CHECK:       [[C]]:
; CHECK-NEXT:    [[TMP1]] = phi i32 [ poison, %[[ENTRY_C_CRIT_EDGE]] ], [ [[DOTPRE2]], %[[FOR_COND5_C_CRIT_EDGE]] ]
; CHECK-NEXT:    [[TMP2:%.*]] = phi i32 [ [[DOTPRE1]], %[[ENTRY_C_CRIT_EDGE]] ], [ 0, %[[FOR_COND5_C_CRIT_EDGE]] ]
; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[TMP2]], 1
; CHECK-NEXT:    [[IDXPROM:%.*]] = zext i32 [[ADD]] to i64
; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr [4 x i8], ptr @b, i64 [[IDXPROM]]
; CHECK-NEXT:    store i32 [[TMP1]], ptr null, align 4
; CHECK-NEXT:    br label %[[FOR_COND5]]
; CHECK:       [[FOR_END8]]:
; CHECK-NEXT:    ret void
;
entry:
  br i1 true, label %for.end4, label %c

for.end4:                                         ; preds = %entry
  store i32 0, ptr getelementptr inbounds nuw (i8, ptr @b, i64 4), align 4
  br label %for.cond5

for.cond5:                                        ; preds = %c, %for.end4
  %0 = load i32, ptr null, align 4
  %cmp6 = icmp eq i32 %0, 0
  br i1 %cmp6, label %c, label %for.end8

c:                                                ; preds = %for.cond5, %entry
  %1 = load i32, ptr null, align 4
  %add = add i32 %1, 1
  %idxprom = zext i32 %add to i64
  %arrayidx = getelementptr [4 x i8], ptr @b, i64 %idxprom
  %2 = load i32, ptr %arrayidx, align 4
  store i32 %2, ptr null, align 4
  br label %for.cond5

for.end8:                                         ; preds = %for.cond5
  ret void
}