--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/CodeGen/X86/coalescer-dce.ll	Thu Dec 12 13:56:28 2013 +0900
@@ -0,0 +1,80 @@
+; RUN: llc < %s -disable-fp-elim -disable-machine-dce -verify-coalescing
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
+target triple = "x86_64-apple-macosx10.7.0"
+
+; This test case has a sub-register join followed by a remat:
+;
+; 256L    %vreg2<def> = COPY %vreg7:sub_32bit<kill>; GR32:%vreg2 GR64:%vreg7
+;         Considering merging %vreg2 with %vreg7:sub_32bit
+;         Cross-class to GR64.
+;                 RHS = %vreg2 = [256d,272d:0)  0@256d
+;                 LHS = %vreg7 = [208d,256d:0)[304L,480L:0)  0@208d
+;                 updated: 272L   %vreg0<def> = COPY %vreg7:sub_32bit<kill>; GR32:%vreg0 GR64:%vreg7
+;         Joined. Result = %vreg7 = [208d,272d:0)[304L,480L:0)  0@208d
+;
+; 272L    %vreg10:sub_32bit<def> = COPY %vreg7:sub_32bit<kill>, %vreg10<imp-def>; GR64:%vreg10,%vreg7
+;         Considering merging %vreg7 with %vreg10
+;                 RHS = %vreg7 = [208d,272d:0)[304L,480L:0)  0@208d
+;                 LHS = %vreg10 = [16d,64L:2)[64L,160L:1)[192L,240L:1)[272d,304L:3)[304L,352d:1)[352d,400d:0)[400d,400S:4)  0@352d 1@64L-phidef 2@16d-phikill 3@272d-phikill 4@400d
+; Remat: %vreg10<def> = MOV64r0 %vreg10<imp-def>, %EFLAGS<imp-def,dead>, %vreg10<imp-def>; GR64:%vreg10
+; Shrink: %vreg7 = [208d,272d:0)[304L,480L:0)  0@208d
+;  live-in at 240L
+;  live-in at 416L
+;  live-in at 320L
+;  live-in at 304L
+; Shrunk: %vreg7 = [208d,256d:0)[304L,480L:0)  0@208d
+;
+; The COPY at 256L is rewritten as a partial def, and that would artificially
+; extend the live range of %vreg7 to end at 256d.  When the joined copy is
+; removed, -verify-coalescing complains about the dangling kill.
+;
+; <rdar://problem/9967101>
+
+define void @f1() nounwind uwtable ssp {
+bb:
+  br label %bb1
+
+bb1:
+  %tmp = phi i32 [ 0, %bb ], [ %tmp21, %bb20 ]
+  br label %bb2
+
+bb2:
+  br i1 undef, label %bb5, label %bb8
+
+bb4:
+  br i1 undef, label %bb2, label %bb20
+
+bb5:
+  br i1 undef, label %bb4, label %bb20
+
+bb8:
+  %tmp9 = phi i32 [ %tmp24, %bb23 ], [ 0, %bb2 ]
+  br i1 false, label %bb41, label %bb10
+
+bb10:
+  %tmp11 = sub nsw i32 %tmp9, %tmp
+  br i1 false, label %bb2, label %bb26
+
+bb20:
+  %tmp21 = phi i32 [ undef, %bb4 ], [ undef, %bb5 ], [ %tmp9, %bb27 ], [ undef, %bb32 ]
+  %tmp22 = phi i32 [ undef, %bb4 ], [ undef, %bb5 ], [ %tmp11, %bb27 ], [ undef, %bb32 ]
+  br label %bb1
+
+bb23:
+  %tmp24 = add nsw i32 %tmp9, 1
+  br label %bb8
+
+bb26:
+  br i1 undef, label %bb27, label %bb32
+
+bb27:
+  %tmp28 = zext i32 %tmp11 to i64
+  %tmp30 = icmp eq i64 undef, %tmp28
+  br i1 %tmp30, label %bb20, label %bb27
+
+bb32:
+  br i1 undef, label %bb20, label %bb23
+
+bb41:
+  ret void
+}