Avoid infinite looping in AllGlobalLoadUsesSimpleEnoughForHeapSRA(). This can happen when PHI uses are recursively dependent on each other.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72710 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Transforms/GlobalOpt/2009-06-01-RecursivePHI.ll b/test/Transforms/GlobalOpt/2009-06-01-RecursivePHI.ll
new file mode 100644
index 0000000..0ce16dd
--- /dev/null
+++ b/test/Transforms/GlobalOpt/2009-06-01-RecursivePHI.ll
@@ -0,0 +1,117 @@
+; RUN: llvm-as < %s | opt -globalopt
+
+	%struct.s_annealing_sched = type { i32, float, float, float, float }
+	%struct.s_bb = type { i32, i32, i32, i32 }
+	%struct.s_net = type { i8*, i32, i32*, float, float }
+	%struct.s_placer_opts = type { i32, float, i32, i32, i8*, i32, i32 }
+@net = internal global %struct.s_net* null		; <%struct.s_net**> [#uses=4]
+
+define fastcc void @alloc_and_load_placement_structs(i32 %place_cost_type, i32 %num_regions, float %place_cost_exp, float*** nocapture %old_region_occ_x, float*** nocapture %old_region_occ_y) nounwind ssp {
+entry:
+	br i1 undef, label %bb.i, label %my_malloc.exit
+
+bb.i:		; preds = %entry
+	unreachable
+
+my_malloc.exit:		; preds = %entry
+	br i1 undef, label %bb.i81, label %my_malloc.exit83
+
+bb.i81:		; preds = %my_malloc.exit
+	unreachable
+
+my_malloc.exit83:		; preds = %my_malloc.exit
+	br i1 undef, label %bb.i.i57, label %my_calloc.exit.i
+
+bb.i.i57:		; preds = %my_malloc.exit83
+	unreachable
+
+my_calloc.exit.i:		; preds = %my_malloc.exit83
+	br i1 undef, label %bb.i4.i, label %my_calloc.exit5.i
+
+bb.i4.i:		; preds = %my_calloc.exit.i
+	unreachable
+
+my_calloc.exit5.i:		; preds = %my_calloc.exit.i
+	%.pre.i58 = load %struct.s_net** @net, align 4		; <%struct.s_net*> [#uses=1]
+	br label %bb17.i78
+
+bb1.i61:		; preds = %bb4.preheader.i, %bb1.i61
+	br i1 undef, label %bb1.i61, label %bb5.i62
+
+bb5.i62:		; preds = %bb1.i61
+	br i1 undef, label %bb6.i64, label %bb15.preheader.i
+
+bb15.preheader.i:		; preds = %bb4.preheader.i, %bb5.i62
+	br label %bb16.i77
+
+bb6.i64:		; preds = %bb5.i62
+	br i1 undef, label %bb7.i65, label %bb8.i67
+
+bb7.i65:		; preds = %bb6.i64
+	unreachable
+
+bb8.i67:		; preds = %bb6.i64
+	br i1 undef, label %bb.i1.i68, label %my_malloc.exit.i70
+
+bb.i1.i68:		; preds = %bb8.i67
+	unreachable
+
+my_malloc.exit.i70:		; preds = %bb8.i67
+	%0 = load %struct.s_net** @net, align 4		; <%struct.s_net*> [#uses=1]
+	br i1 undef, label %bb9.i71, label %bb16.i77
+
+bb9.i71:		; preds = %bb9.i71, %my_malloc.exit.i70
+	%1 = load %struct.s_net** @net, align 4		; <%struct.s_net*> [#uses=1]
+	br i1 undef, label %bb9.i71, label %bb16.i77
+
+bb16.i77:		; preds = %bb9.i71, %my_malloc.exit.i70, %bb15.preheader.i
+	%.pre41.i.rle244 = phi %struct.s_net* [ %.pre41.i, %bb15.preheader.i ], [ %0, %my_malloc.exit.i70 ], [ %1, %bb9.i71 ]		; <%struct.s_net*> [#uses=1]
+	br label %bb17.i78
+
+bb17.i78:		; preds = %bb16.i77, %my_calloc.exit5.i
+	%.pre41.i = phi %struct.s_net* [ %.pre41.i.rle244, %bb16.i77 ], [ %.pre.i58, %my_calloc.exit5.i ]		; <%struct.s_net*> [#uses=1]
+	br i1 undef, label %bb4.preheader.i, label %alloc_and_load_unique_pin_list.exit
+
+bb4.preheader.i:		; preds = %bb17.i78
+	br i1 undef, label %bb1.i61, label %bb15.preheader.i
+
+alloc_and_load_unique_pin_list.exit:		; preds = %bb17.i78
+	ret void
+}
+
+define void @read_net(i8* %net_file) nounwind ssp {
+entry:
+	br i1 undef, label %bb3.us.us.i, label %bb6.preheader
+
+bb6.preheader:		; preds = %entry
+	br i1 undef, label %bb7, label %bb
+
+bb3.us.us.i:		; preds = %entry
+	unreachable
+
+bb:		; preds = %bb6.preheader
+	br i1 undef, label %bb.i34, label %bb1.i38
+
+bb.i34:		; preds = %bb
+	unreachable
+
+bb1.i38:		; preds = %bb
+	%0 = malloc %struct.s_net, i32 undef		; <%struct.s_net*> [#uses=1]
+	br i1 undef, label %bb.i1.i39, label %my_malloc.exit2.i
+
+bb.i1.i39:		; preds = %bb1.i38
+	unreachable
+
+my_malloc.exit2.i:		; preds = %bb1.i38
+	store %struct.s_net* %0, %struct.s_net** @net, align 4
+	br i1 undef, label %bb.i7.i40, label %my_malloc.exit8.i
+
+bb.i7.i40:		; preds = %my_malloc.exit2.i
+	unreachable
+
+my_malloc.exit8.i:		; preds = %my_malloc.exit2.i
+	unreachable
+
+bb7:		; preds = %bb6.preheader
+	unreachable
+}