From bc70ff3cb977fd69e120d89b0e04f316d87cdbef Mon Sep 17 00:00:00 2001
From: Jakob Stoklund Olesen <stoklund@2pi.dk>
Date: Mon, 13 Aug 2012 20:49:04 +0000
Subject: Handle extra Tail predecessors in if-conversion.

It is still possible to if-convert if the tail block has extra
predecessors, but the tail phis must be rewritten instead of being
removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161781 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/CodeGen/X86/early-ifcvt.ll | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

(limited to 'test/CodeGen/X86/early-ifcvt.ll')

diff --git a/test/CodeGen/X86/early-ifcvt.ll b/test/CodeGen/X86/early-ifcvt.ll
index ce1fe04f98..7883ffabd5 100644
--- a/test/CodeGen/X86/early-ifcvt.ll
+++ b/test/CodeGen/X86/early-ifcvt.ll
@@ -37,3 +37,33 @@ do.end:
   %sub = sub nsw i32 %max.1, %min.1
   ret i32 %sub
 }
+
+; CHECK: multipreds
+; Deal with alternative tail predecessors
+; CHECK-NOT: LBB
+; CHECK: cmov
+; CHECK-NOT: LBB
+; CHECK: cmov
+; CHECK-NOT: LBB
+; CHECK: fprintf
+
+define void @multipreds(i32 %sw) nounwind uwtable ssp {
+entry:
+  switch i32 %sw, label %if.then29 [
+    i32 0, label %if.then37
+    i32 127, label %if.end41
+  ]
+
+if.then29:
+  br label %if.end41
+
+if.then37:
+  br label %if.end41
+
+if.end41:
+  %exit_status.0 = phi i32 [ 2, %if.then29 ], [ 0, %if.then37 ], [ 66, %entry ]
+  call void (...)* @fprintf(i32 %exit_status.0) nounwind
+  unreachable
+}
+
+declare void @fprintf(...) nounwind
-- 
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