C2 compiler fails in elide_copy()

The stack trace from dbx.

----------------- lwp# 31 / thread# 31 --------------------
 ff2c642c _lwp_kill (6, 0, ff2f2e18, feaf638c, ffffffff, 6) + 8
 ff241198 abort (2d790, 1, fec086a0, ad260, ff2f12d8, 0) + 110
 feaf638c void os::abort(bool) (1, fedca58c, 1, fedb2000, 1858c, 18400) + 5c
 fec086a0 void VMError::report_and_die() (feded498, 0, 1, fed6071b, fed66dc6, fedf2cd8) + d2c
 fe82f6e4 void report_fatal(const char*,int,const char*) (fed090db, b3, fed09116, 148e, 38b9d08, 1b68) + 24
 feb1e290 int PhaseChaitin::elide_copy(Node*,int,Block*,Node_List&,Node_List&,bool) (38b9d40, 306b168, 0, 1ae3be4, 320aa28, 320aa08) + a8
 fe5a3e44 void PhaseChaitin::post_allocate_copy_removal() (593fe9a0, a, 20, 0, 4, 2) + 24c
 fe59e5f8 void PhaseChaitin::Register_Allocate() (593fe9a0, bf2, 6, fedb2000, 3b9d554, 3b9d160) + d44
 fe5a0d28 void Compile::Code_Gen() (0, 593ff3a8, 0, fedb2000, 593fe9a0, 593ff3a8) + 398
 fe7f5d3c Compile::Compile #Nvariant 1(ciEnv*,C2Compiler*,ciMethod*,int,bool,bool) (593ff3a8, 298db8, 2a6f28, 593ff3a8, fedfa9d4, fec945cf) + cd4
 fe5ba5e4 void C2Compiler::compile_method(ciEnv*,ciMethod*,int) (2a6f28, 593ff9ec, 2876b28, ffffffff, fec75fda, 0) + 80
 fe5bb3e4 void CompileBroker::invoke_compiler_on_method(CompileTask*) (34e50e0, 11cc00, 850, 0, fe5ba564, 2b7000) + 9e8
 fe634cac void CompileBroker::compiler_thread_loop() (0, fedec480, 2b7000, 298d10, 2f400, 2f400) + 65c
 febb50e0 void JavaThread::thread_main_inner() (2b7000, 2b7628, 1f, f, fedb2000, 0) + 48
 feaf54e8 java_start (2b7000, 49f3, fedb2000, fecffe39, 2b85c0, fedfb3e4) + 22c
 ff2c5238 _lwp_start (0, 0, 0, 0, 0, 0)