ProcessImplicitDefs should watch out for invalidated iterator and extra implicit operands on copies.

llvm-svn: 89880
diff --git a/llvm/test/CodeGen/PowerPC/2009-11-25-ImpDefBug.ll b/llvm/test/CodeGen/PowerPC/2009-11-25-ImpDefBug.ll
new file mode 100644
index 0000000..9a22a6f
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/2009-11-25-ImpDefBug.ll
@@ -0,0 +1,56 @@
+; RUN: llc < %s -mtriple=powerpc-apple-darwin9.5 -mcpu=g5
+; rdar://7422268
+
+%struct..0EdgeT = type { i32, i32, float, float, i32, i32, i32, float, i32, i32 }
+
+define void @smooth_color_z_triangle(i32 %v0, i32 %v1, i32 %v2, i32 %pv) nounwind {
+entry:
+  br i1 undef, label %return, label %bb14
+
+bb14:                                             ; preds = %entry
+  br i1 undef, label %bb15, label %return
+
+bb15:                                             ; preds = %bb14
+  br i1 undef, label %bb16, label %bb17
+
+bb16:                                             ; preds = %bb15
+  br label %bb17
+
+bb17:                                             ; preds = %bb16, %bb15
+  %0 = fcmp olt float undef, 0.000000e+00         ; <i1> [#uses=2]
+  %eTop.eMaj = select i1 %0, %struct..0EdgeT* undef, %struct..0EdgeT* null ; <%struct..0EdgeT*> [#uses=1]
+  br label %bb69
+
+bb24:                                             ; preds = %bb69
+  br i1 undef, label %bb25, label %bb28
+
+bb25:                                             ; preds = %bb24
+  br label %bb33
+
+bb28:                                             ; preds = %bb24
+  br i1 undef, label %return, label %bb32
+
+bb32:                                             ; preds = %bb28
+  br i1 %0, label %bb38, label %bb33
+
+bb33:                                             ; preds = %bb32, %bb25
+  br i1 undef, label %bb34, label %bb38
+
+bb34:                                             ; preds = %bb33
+  br label %bb38
+
+bb38:                                             ; preds = %bb34, %bb33, %bb32
+  %eRight.08 = phi %struct..0EdgeT* [ %eTop.eMaj, %bb32 ], [ undef, %bb34 ], [ undef, %bb33 ] ; <%struct..0EdgeT*> [#uses=0]
+  %fdgOuter.0 = phi i32 [ %fdgOuter.1, %bb32 ], [ undef, %bb34 ], [ %fdgOuter.1, %bb33 ] ; <i32> [#uses=1]
+  %fz.3 = phi i32 [ %fz.2, %bb32 ], [ 2147483647, %bb34 ], [ %fz.2, %bb33 ] ; <i32> [#uses=1]
+  %1 = add i32 undef, 1                           ; <i32> [#uses=0]
+  br label %bb69
+
+bb69:                                             ; preds = %bb38, %bb17
+  %fdgOuter.1 = phi i32 [ undef, %bb17 ], [ %fdgOuter.0, %bb38 ] ; <i32> [#uses=2]
+  %fz.2 = phi i32 [ undef, %bb17 ], [ %fz.3, %bb38 ] ; <i32> [#uses=2]
+  br i1 undef, label %bb24, label %return
+
+return:                                           ; preds = %bb69, %bb28, %bb14, %entry
+  ret void
+}