; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes='default<O2>' -S < %s | FileCheck %s

define void @PR47852(ptr noundef %d, i32 noundef %c) {
; CHECK-LABEL: @PR47852(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CMP_NOT1:%.*]] = icmp eq i32 [[C:%.*]], 0
; CHECK-NEXT:    br i1 [[CMP_NOT1]], label [[WHILE_END:%.*]], label [[WHILE_BODY_PREHEADER:%.*]]
; CHECK:       while.body.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = zext i32 [[C]] to i64
; CHECK-NEXT:    tail call void @llvm.memset.p0.i64(ptr align 1 [[D:%.*]], i8 0, i64 [[TMP0]], i1 false)
; CHECK-NEXT:    br label [[WHILE_END]]
; CHECK:       while.end:
; CHECK-NEXT:    ret void
;
entry:
  br label %while.cond

while.cond:
  %c.addr.0 = phi i32 [ %c, %entry ], [ %dec, %while.body ]
  %d.addr.0 = phi ptr [ %d, %entry ], [ %incdec.ptr, %while.body ]
  %dec = add i32 %c.addr.0, -1
  %cmp = icmp ugt i32 %c.addr.0, 0
  br i1 %cmp, label %while.body, label %while.end

while.body:
  %incdec.ptr = getelementptr inbounds i8, ptr %d.addr.0, i32 1
  store i8 0, ptr %d.addr.0, align 1
  br label %while.cond

while.end:
  ret void
}