1 files changed, 44 insertions, 0 deletions
diff --git a/test/CodeGen/ARM/tail-dup.ll b/test/CodeGen/ARM/tail-dup.ll
new file mode 100644
index 0000000..e015bf0
--- /dev/null
+++ b/test/CodeGen/ARM/tail-dup.ll
@@ -0,0 +1,44 @@
+; RUN: llc < %s -mtriple=thumb-apple-darwin -relocation-model=dynamic-no-pic -mcpu=cortex-a8 -asm-verbose=false | FileCheck %s
+
+; We should be able to tail-duplicate the basic block containing the indirectbr
+; into all of its predecessors.
+; CHECK: fn:
+; CHECK: mov pc
+; CHECK: mov pc
+; CHECK: mov pc
+
+@fn.codetable = internal unnamed_addr constant [3 x i8*] [i8* blockaddress(@fn, %RETURN), i8* blockaddress(@fn, %INCREMENT), i8* blockaddress(@fn, %DECREMENT)], align 4
+
+define i32 @fn(i32* nocapture %opcodes) nounwind readonly ssp {
+entry:
+  %0 = load i32* %opcodes, align 4, !tbaa !0
+  %arrayidx = getelementptr inbounds [3 x i8*]* @fn.codetable, i32 0, i32 %0
+  br label %indirectgoto
+
+INCREMENT:                                        ; preds = %indirectgoto
+  %inc = add nsw i32 %result.0, 1
+  %1 = load i32* %opcodes.addr.0, align 4, !tbaa !0
+  %arrayidx2 = getelementptr inbounds [3 x i8*]* @fn.codetable, i32 0, i32 %1
+  br label %indirectgoto
+
+DECREMENT:                                        ; preds = %indirectgoto
+  %dec = add nsw i32 %result.0, -1
+  %2 = load i32* %opcodes.addr.0, align 4, !tbaa !0
+  %arrayidx4 = getelementptr inbounds [3 x i8*]* @fn.codetable, i32 0, i32 %2
+  br label %indirectgoto
+
+indirectgoto:                                     ; preds = %DECREMENT, %INCREMENT, %entry
+  %result.0 = phi i32 [ 0, %entry ], [ %dec, %DECREMENT ], [ %inc, %INCREMENT ]
+  %opcodes.pn = phi i32* [ %opcodes, %entry ], [ %opcodes.addr.0, %DECREMENT ], [ %opcodes.addr.0, %INCREMENT ]
+  %indirect.goto.dest.in = phi i8** [ %arrayidx, %entry ], [ %arrayidx4, %DECREMENT ], [ %arrayidx2, %INCREMENT ]
+  %opcodes.addr.0 = getelementptr inbounds i32* %opcodes.pn, i32 1
+  %indirect.goto.dest = load i8** %indirect.goto.dest.in, align 4
+  indirectbr i8* %indirect.goto.dest, [label %RETURN, label %INCREMENT, label %DECREMENT]
+
+RETURN:                                           ; preds = %indirectgoto
+  ret i32 %result.0
+}
+
+!0 = metadata !{metadata !"int", metadata !1}
+!1 = metadata !{metadata !"omnipotent char", metadata !2}
+!2 = metadata !{metadata !"Simple C/C++ TBAA", null}