Remove dead SD nodes after the combining pass. Fixes PR12201.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154786 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index d1b998f..0914c66 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1080,6 +1080,7 @@ void DAGCombiner::Run(CombineLevel AtLevel) {
 
   // If the root changed (e.g. it was a dead load, update the root).
   DAG.setRoot(Dummy.getValue());
+  DAG.RemoveDeadNodes();
 }
 
 SDValue DAGCombiner::visit(SDNode *N) {

diff --git a/test/CodeGen/PowerPC/ppc-vaarg-agg.ll b/test/CodeGen/PowerPC/ppc-vaarg-agg.ll
new file mode 100644 (file)
index 0000000..d5ea044
--- /dev/null
+++ b/test/CodeGen/PowerPC/ppc-vaarg-agg.ll
@@ -0,0 +1,46 @@
+target datalayout = "E-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v128:128:128-n32"
+target triple = "powerpc-montavista-linux-gnuspe"
+; RUN: llc < %s -march=ppc32 | FileCheck %s
+
+%struct.__va_list_tag.0.9.18.23.32.41.48.55.62.67.72.77.82.87.90.93.96.101.105 = type { i8, i8, i16, i8*, i8* }
+
+define fastcc void @test1(%struct.__va_list_tag.0.9.18.23.32.41.48.55.62.67.72.77.82.87.90.93.96.101.105* %args) {
+entry:
+  br i1 undef, label %repeat, label %maxlen_reached
+
+repeat:                                           ; preds = %entry
+  switch i32 undef, label %sw.bb323 [
+    i32 77, label %sw.bb72
+    i32 111, label %sw.bb309
+    i32 80, label %sw.bb313
+    i32 117, label %sw.bb326
+    i32 88, label %sw.bb321
+  ]
+
+sw.bb72:                                          ; preds = %repeat
+  unreachable
+
+sw.bb309:                                         ; preds = %repeat
+  unreachable
+
+sw.bb313:                                         ; preds = %repeat
+  unreachable
+
+sw.bb321:                                         ; preds = %repeat
+  unreachable
+
+sw.bb323:                                         ; preds = %repeat
+  %0 = va_arg %struct.__va_list_tag.0.9.18.23.32.41.48.55.62.67.72.77.82.87.90.93.96.101.105* %args, i32
+  unreachable
+
+sw.bb326:                                         ; preds = %repeat
+  unreachable
+
+maxlen_reached:                                   ; preds = %entry
+  ret void
+}
+
+; If the SD nodes are not cleaup up correctly, then this can fail to compile
+; with an error like:  Cannot select: ch = setlt [ID=6]
+; CHECK: @test1
+