llvm/test/Transforms/NewGVN/load-from-unreachable-predecessor.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
; RUN: opt -passes=newgvn -S < %s | FileCheck %s

; Check that an unreachable predecessor to a PHI node doesn't cause a crash.
; PR21625.

define i32 @f(ptr %f) {
; CHECK-LABEL: define i32 @f(
; CHECK-SAME: ptr [[F:%.*]]) {
; CHECK-NEXT:  bb0:
; CHECK-NEXT:    br label [[BB2:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    store i8 poison, ptr null, align 1
; CHECK-NEXT:    br i1 false, label [[BB1:%.*]], label [[BB2]]
; CHECK:       bb2:
; CHECK-NEXT:    [[STOREMERGE:%.*]] = load i32, ptr null, align 4
; CHECK-NEXT:    ret i32 [[STOREMERGE]]
;
; Load should be removed, since it's ignored.
bb0:
  %bar = load ptr, ptr %f
  br label %bb2
bb1:
  %zed = load ptr, ptr %f
  br i1 false, label %bb1, label %bb2
bb2:
  %foo = phi ptr [ null, %bb0 ], [ %zed, %bb1 ]
  %storemerge = load i32, ptr %foo
  ret i32 %storemerge
}