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; RUN: opt -codegenprepare -S -mtriple=x86_64-linux < %s | FileCheck %s
; The ret instruction can be duplicated into BB case2 even though there is an
; intermediate BB exit1 and call to llvm.assume.
@ptr = external global ptr, align 8
; CHECK: %ret1 = tail call ptr @qux()
; CHECK-NEXT: ret ptr %ret1
; CHECK: %ret2 = tail call ptr @bar()
; CHECK-NEXT: ret ptr %ret2
define ptr @foo(i64 %size, i64 %v1, i64 %v2) {
entry:
%a = alloca i8
call void @llvm.lifetime.start.p0(i64 -1, ptr %a) nounwind
%cmp1 = icmp ult i64 %size, 1025
br i1 %cmp1, label %if.end, label %case1
case1:
%ret1 = tail call ptr @qux()
br label %exit2
if.end:
%cmp2 = icmp ult i64 %v1, %v2
br i1 %cmp2, label %case3, label %case2
case2:
%ret2 = tail call ptr @bar()
br label %exit1
case3:
%ret3 = load ptr, ptr @ptr, align 8
br label %exit1
exit1:
%retval1 = phi ptr [ %ret2, %case2 ], [ %ret3, %case3 ]
%cmp3 = icmp ne ptr %retval1, null
tail call void @llvm.assume(i1 %cmp3)
br label %exit2
exit2:
%retval2 = phi ptr [ %ret1, %case1 ], [ %retval1, %exit1 ]
call void @llvm.lifetime.end.p0(i64 -1, ptr %a) nounwind
ret ptr %retval2
}
declare void @llvm.assume(i1)
declare ptr @qux()
declare ptr @bar()
declare void @llvm.lifetime.start.p0(i64, ptr nocapture) nounwind
declare void @llvm.lifetime.end.p0(i64, ptr nocapture) nounwind
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