Treat TargetGlobalAddress as a constant for the purpose of matching pre-inc stores on PPC.

Thanks to Tobias von Koch for pointing out this problem.

llvm-svn: 158932
diff --git a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index b53deda..a00f686 100644
--- a/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -111,7 +111,8 @@
     /// immediate field.  Because preinc imms have already been validated, just
     /// accept it.
     bool SelectAddrImmOffs(SDValue N, SDValue &Out) const {
-      if (isa<ConstantSDNode>(N)) {
+      if (isa<ConstantSDNode>(N) || N.getOpcode() == PPCISD::Lo ||
+          N.getOpcode() == ISD::TargetGlobalAddress) {
         Out = N;
         return true;
       }
@@ -123,6 +124,10 @@
     /// index field.  Because preinc imms have already been validated, just
     /// accept it.
     bool SelectAddrIdxOffs(SDValue N, SDValue &Out) const {
+      if (isa<ConstantSDNode>(N) || N.getOpcode() == PPCISD::Lo ||
+          N.getOpcode() == ISD::TargetGlobalAddress)
+        return false;
+
       Out = N;
       return true;
     }
diff --git a/llvm/test/CodeGen/PowerPC/stwu-gta.ll b/llvm/test/CodeGen/PowerPC/stwu-gta.ll
new file mode 100644
index 0000000..4febe7e
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/stwu-gta.ll
@@ -0,0 +1,22 @@
+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-unknown-linux"
+; RUN: llc < %s | FileCheck %s
+
+%class.Two.0.5 = type { i32, i32, i32 }
+
+@foo = external global %class.Two.0.5, align 4
+
+define void @_GLOBAL__I_a() nounwind section ".text.startup" {
+entry:
+  store i32 5, i32* getelementptr inbounds (%class.Two.0.5* @foo, i32 0, i32 0), align 4, !tbaa !0
+  store i32 6, i32* getelementptr inbounds (%class.Two.0.5* @foo, i32 0, i32 1), align 4, !tbaa !0
+  ret void
+}
+
+; CHECK: @_GLOBAL__I_a
+; CHECK-NOT: stwux
+; CHECK: stwu
+
+!0 = metadata !{metadata !"int", metadata !1}
+!1 = metadata !{metadata !"omnipotent char", metadata !2}
+!2 = metadata !{metadata !"Simple C/C++ TBAA"}