The stack trace shows in the SAME core.
current thread: t@7
=>[1] __lwp_kill(0x0, 0x6, 0x0, 0xff33c000, 0xfee591dc, 0x142e7c), at 0xff31f82c
  [2] raise(0x6, 0x0, 0xb477e120, 0x722c, 0x8154, 0x8000), at 0xff2d0a1c
  [3] abort(0x6800, 0xfef9c000, 0xfee59178, 0xfeff07ec, 0x0, 0x34290), at 0xff2b6cd8
  [4] os::abort(0x1, 0x0, 0xfefcff3c, 0xfef9c000, 0x7134, 0x7000), at 0xfee53234
  [5] VMError::report_and_die(0x0, 0xfeff6b78, 0xfeff07c4, 0x1, 0xfee572ac, 0xfeff07c4), at 0xfeed2dc0
  [6] JVM_handle_solaris_signal(0xb, 0xb477e820, 0xb477e568, 0x7400, 0xfefef7f4, 0x145440), at 0xfea73d44
  [7] __sighndlr(0xb, 0xb477e820, 0xb477e568, 0xfea73260, 0x0, 0x0), at 0xff385bac
  ---- called from signal handler with signal 11 (SIGSEGV) ------
  [8] FastLockNode::Ideal(0xfefdc24c, 0xb477ee5c, 0x0, 0xd65b24, 0xb477ee5c, 0xd66310), at 0xfee221bc
  [9] PhaseIterGVN::transform_old(0xb477ee5c, 0xd662ac, 0x6875d0, 0xfee219f8, 0x1, 0x204), at 0xfe8f6250
  [10] PhaseIterGVN::optimize(0xb477ee5c, 0x7c, 0xd662ac, 0x0, 0xb477efac, 0xffffffff), at 0xfe9e0d04
  [11] Compile::Optimize(0xb477f418, 0x136528, 0x8048, 0x8000, 0xfef9c000, 0x1000), at 0xfea7cf9c
  [12] Compile::Compile(0xb477f418, 0x0, 0x34f90, 0x0, 0xfef19bc4, 0xb477f418), at 0xfea7fcf0
  [13] C2Compiler::compile_method(0xb477fd14, 0xfef05d14, 0xa575f0, 0xffffffff, 0x34f90, 0x100000a), at 0xfea75c14
  [14] CompileBroker::invoke_compiler_on_method(0x2094050, 0x145a14, 0x136528, 0x145440, 0xfef1a573, 0xb477fd14), at 0xfea768d0
  [15] CompileBroker::compiler_thread_loop(0xfefef908, 0x1364f8, 0x145440, 0xf6737bf0, 0x145a10, 0x0), at 0xfeb32138
  [16] JavaThread::run(0x145440, 0x0, 0xfefe9c80, 0x6800, 0x7b38, 0x7800), at 0xfeada834
  [17] _start(0x145440, 0x446d, 0xfef9c000, 0x0, 0x4ee0, 0x4c00), at 0xfee52d50
and

current thread: t@8
=>[1] _libc_nanosleep(0x4, 0xb467e0b0, 0x1, 0x0, 0x0, 0x590a04), at 0xff31c2f4
  [2] _sleep(0x64, 0xfef5d5a6, 0x1, 0x0, 0xf2, 0xd3), at 0xff37dc5c
  [3] os::infinite_sleep(0xfeff6b78, 0xfef5d5a6, 0x1, 0x1, 0x1f, 0x64), at 0xfee549c8
  [4] VMError::report_and_die(0xb467e270, 0xfeff6b78, 0xb, 0x0, 0x0, 0x5c00), at 0xfeed23e4
  [5] crash_handler(0xb, 0x0, 0xb467e468, 0x0, 0x0, 0x0), at 0xfeed31bc
  [6] __sighndlr(0xb, 0x0, 0xb467e468, 0xfeed3178, 0x0, 0x0), at 0xff385bac
  ---- called from signal handler with signal 11 (SIGSEGV) ------
  [7] FastLockNode::Ideal(0xfefdc24c, 0xb467ecdc, 0x0, 0x650020, 0xb467ecdc, 0x65080c), at 0xfee221bc
  [8] PhaseIterGVN::transform_old(0xb467ecdc, 0x6507a8, 0x2078c90, 0xfee219f8, 0x80000, 0x19e), at 0xfe8f6250
  [9] PhaseIterGVN::optimize(0xb467ecdc, 0x76, 0x6507a8, 0x0, 0xb467ee2c, 0xffffffff), at 0xfe9e0d04
  [10] Compile::Optimize(0xb467f298, 0x136558, 0x8048, 0x8000, 0xfef9c000, 0x1000), at 0xfea7cf9c
  [11] Compile::Compile(0xb467f298, 0x0, 0x34f90, 0x0, 0xfef19bc4, 0xb467f298), at 0xfea7fcf0
  [12] C2Compiler::compile_method(0xb467fb94, 0xfef05d14, 0x3cc240, 0xffffffff, 0x34f90, 0x1000009), at 0xfea75c14
  [13] CompileBroker::invoke_compiler_on_method(0x3106c8, 0x14691c, 0x136558, 0x146348, 0xfef1a573, 0xb467fb94), at 0xfea768d0
  [14] CompileBroker::compiler_thread_loop(0xfefef908, 0x1364f8, 0x146348, 0xf5a6f9b8, 0x146918, 0x0), at 0xfeb32138
  [15] JavaThread::run(0x146348, 0x0, 0xfefe9c80, 0x6800, 0x7b38, 0x7800), at 0xfeada834
  [16] _start(0x146348, 0x446d, 0xfef9c000, 0x0, 0x4ee0, 0x4c00), at 0xfee52d50