G1 barriers fail with 64bit c1 with the following symptoms:

1. On x64:

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/tmp/jprt/P1/B/164731.jcoomes/source/src/share/vm/c1/c1_LIR.hpp:401), pid=13281, tid=20
# assert(is_single_cpu() && !is_virtual()) failed: type check
#
# JRE version: 7.0
# Java VM: Java HotSpot(TM) 64-Bit Server VM (20.0-b01-201010081647.jcoomes.gc-pull-fastdebug mixed mode solaris-amd64 )
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#

--------------- T H R E A D ---------------

Current thread (0x0000000009ad9800): JavaThread "C1 CompilerThread2" daemon [_thread_in_native, id=20, stack(0xfffffd7f6bb43000,0xfffffd7f6bc43000)]

Stack: [0xfffffd7f6bb43000,0xfffffd7f6bc43000], sp=0xfffffd7f6bc411a0, free space=1016k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x2485615];; __1cHVMErrorGreport6MpnMoutputStream__v_+0x6c5
V [libjvm.so+0x24866bc];; __1cHVMErrorOreport_and_die6M_v_+0x4d8
V [libjvm.so+0xde50a7];; __1cPreport_vm_error6Fpkci11_v_+0x55f
V [libjvm.so+0x88778d];; __1cLLIR_OprDescLas_register6kM_pnMRegisterImpl__+0x6d5
V [libjvm.so+0x80075a];; __1cRG1PostBarrierStubJemit_code6MpnNLIR_Assembler__v_+0xb2
V [libjvm.so+0x8c38b5];; __1cNLIR_AssemblerUemit_slow_case_stubs6M_v_+0x16d
V [libjvm.so+0x807f7c];; __1cLCompilationOemit_code_body6M_i_+0x134
V [libjvm.so+0x808b77];; __1cLCompilationTcompile_java_method6M_i_+0xa73
V [libjvm.so+0x80a787];; __1cLCompilation2t6MpnQAbstractCompiler_pnFciEnv_pnIciMethod_ipnKBufferBlob__v_+0x3df
V [libjvm.so+0x80c69a];; __1cICompilerOcompile_method6MpnFciEnv_pnIciMethod_i_v_+0x27e
V [libjvm.so+0xc6fe33];; __1cNCompileBrokerZinvoke_compiler_on_method6FpnLCompileTask__v_+0x18df
V [libjvm.so+0xc6d694];; __1cNCompileBrokerUcompiler_thread_loop6F_v_+0xeb0
V [libjvm.so+0x23427f9];; __1cKJavaThreadRthread_main_inner6M_v_+0x195
V [libjvm.so+0x234244a];; __1cKJavaThreadDrun6M_v_+0x61e
V [libjvm.so+0x1ec02e2];; java_start+0x6a6
C [libc.so.1+0xd6e3b] _thr_slot_offset+0x31b;; _thr_setup+0x5b
C [libc.so.1+0xd7070] _thr_slot_offset+0x550;; _lwp_start+0x0



2. On sparcv9:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/tmp/jprt/P1/B/164731.jcoomes/source/src/cpu/sparc/vm/assembler_sparc.hpp:843), pid=17818, tid=20
# assert(nbits == 32 || -(1 << nbits-1) <= x && x < ( 1 << nbits-1)) failed: value out of range
#
# JRE version: 7.0
# Java VM: Java HotSpot(TM) 64-Bit Server VM (20.0-b01-201010081647.jcoomes.gc-pull-fastdebug mixed mode solaris-sparc )
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#

--------------- T H R E A D ---------------

Current thread (0x0000000109740000): JavaThread "C1 CompilerThread2" daemon [_thread_in_native, id=20, stack(0xffffffff4b900000,0xffffffff4ba00000)]

Stack: [0xffffffff4b900000,0xffffffff4ba00000], sp=0xffffffff4b9fe450, free space=1017k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x12a72ec];; __1cHVMErrorOreport_and_die6M_v_+0x734
V [libjvm.so+0x70bbb0];; __1cPreport_vm_error6Fpkci11_v_+0x78
V [libjvm.so+0x221290];; __1cJAssemblerTassert_signed_range6Fli_v_+0x70
V [libjvm.so+0x214ee4];; __1cJAssemblerHwdisp166Fll_i_+0x2c
V [libjvm.so+0x314d60];; __1cOMacroAssemblerObr_on_reg_cond6MnJAssemblerKRCondition_bn0BHPredict_pnMRegisterImpl_rnFLabel__v_+0x2f8
V [libjvm.so+0x39fea4];; __1cQG1PreBarrierStubJemit_code6MpnNLIR_Assembler__v_+0xe4
V [libjvm.so+0x3ffc98];; __1cNLIR_AssemblerKemit_stubs6MpnMCodeStubList__v_+0x138
V [libjvm.so+0x3a41dc];; __1cLCompilationQemit_code_epilog6MpnNLIR_Assembler__v_+0x34
V [libjvm.so+0x3a4484];; __1cLCompilationOemit_code_body6M_i_+0x10c
V [libjvm.so+0x3a495c];; __1cLCompilationTcompile_java_method6M_i_+0x414
V [libjvm.so+0x3a4be8];; __1cLCompilationOcompile_method6M_v_+0xb0
V [libjvm.so+0x3a5878];; __1cLCompilation2t6MpnQAbstractCompiler_pnFciEnv_pnIciMethod_ipnKBufferBlob__v_+0x1f8
V [libjvm.so+0x3a8790];; __1cICompilerOcompile_method6MpnFciEnv_pnIciMethod_i_v_+0x3b8
V [libjvm.so+0x659ef8];; __1cNCompileBrokerZinvoke_compiler_on_method6FpnLCompileTask__v_+0x1d70
V [libjvm.so+0x657b44];; __1cNCompileBrokerUcompiler_thread_loop6F_v_+0xb24
V [libjvm.so+0x11d6ffc];; __1cKJavaThreadRthread_main_inner6M_v_+0x1a4
V [libjvm.so+0x11d6e38];; __1cKJavaThreadDrun6M_v_+0x248
V [libjvm.so+0xf1dad0];; java_start+0x300