Following test program fails with

Fatal: SoftMatchFailure is not allowed except in product

java -Xcomp Endian

import java.nio.*;

class Endian {
  public static void main(String[] args) {
    ByteBuffer bb = ByteBuffer.allocate(100);
    ByteOrder bo = bb.order();
    System.out.println(bo.toString());
  }
}

No matching rule for:
--N: o100 RShiftI <== _ o99 o98 <<o84 o217 o102 o118 o110 o116 o210 7 15 18 21 >>

   --N: o99 LShiftI <== _ o78 o98 <<o100 >>

      --N: o78 ConL <== o0 <<o99 o90 >> #long[72623859790382856]
      IREGL 1 IREGL
      IO01REGL 2 IO01REGL
      IO23REGL 2 IO23REGL
      STACKSLOTL 200 regL_to_stkL

      --N: o98 ConI <== o0 <<o99 o100 >> #int:24
      IMMI 5 IMMI
      IMMI13 1 IMMI13
      IMMU13 1 IMMU13
      IMMI11 1 IMMI11
      IREGI 101 loadConI13
      NOTEMP_IREGI 103 loadConI13
      G1REGI 102 loadConI13
      O0REGI 102 loadConI13
      O1REGI 102 loadConI13
      O2REGI 102 loadConI13
      O3REGI 102 loadConI13
      O4REGI 102 loadConI13
      O5REGI 102 loadConI13
      L7REGI 102 loadConI13
      IREGP 201 moveIP
      SP_OR_IREGP 202 moveIP
      NOTEMP_IREGP 203 moveIP
      G1REGP 202 moveIP
      G3REGP 202 moveIP
      G3REGI 102 loadConI13
      G4REGP 202 moveIP
      G5REGP 202 moveIP
      I0REGP 202 moveIP
      O0REGP 202 moveIP
      O1REGP 202 moveIP
      O2REGP 202 moveIP
      O7REGP 202 moveIP
      L7REGP 202 moveIP
      O7REGI 102 loadConI13
      INLINE_CACHE_REGP 202 moveIP
      COMPILER_METHOD_OOP_REGP 202 moveIP
      INTERPRETER_METHOD_OOP_REGP 202 moveIP
      INDIRECT 301 moveIP
      STACKSLOTI 301 regI_to_stkI
      MEMORY 301 INDIRECT

   --N: o98 ConI <== o0 <<o99 o100 >> #int:24
   IMMI 5 IMMI
   IMMI13 1 IMMI13
   IMMU13 1 IMMU13
   IMMI11 1 IMMI11
   IREGI 101 loadConI13
   NOTEMP_IREGI 103 loadConI13
   G1REGI 102 loadConI13
   O0REGI 102 loadConI13
   O1REGI 102 loadConI13
   O2REGI 102 loadConI13
   O3REGI 102 loadConI13
   O4REGI 102 loadConI13
   O5REGI 102 loadConI13
   L7REGI 102 loadConI13
   IREGP 201 moveIP
   SP_OR_IREGP 202 moveIP
   NOTEMP_IREGP 203 moveIP
   G1REGP 202 moveIP
   G3REGP 202 moveIP
   G3REGI 102 loadConI13
   G4REGP 202 moveIP
   G5REGP 202 moveIP
   I0REGP 202 moveIP
   O0REGP 202 moveIP
   O1REGP 202 moveIP
   O2REGP 202 moveIP
   O7REGP 202 moveIP
   L7REGP 202 moveIP
   O7REGI 102 loadConI13
   INLINE_CACHE_REGP 202 moveIP
   COMPILER_METHOD_OOP_REGP 202 moveIP
   INTERPRETER_METHOD_OOP_REGP 202 moveIP
   INDIRECT 301 moveIP
   STACKSLOTI 301 regI_to_stkI
   MEMORY 301 INDIRECT

#
# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Fatal: SoftMatchFailure is not allowed except in product
#
# Error ID: /files/ws/c2_work/build/solaris/../../src/share/vm/opto/matcher.hpp, 303 [ Patched ]
#

With sun/misc/Unsafe it's possible to store a word and reload a byte
from the same address. The C2 optimizer tries to replace the load
with the input to the store, but fails to consider the byteorder in
memory. The store word and reload byte case fails on a big Endian
machine like sparc.

109! java.nio.Bits::byteOrder (119 bytes)
 87 IfTrue <== 81 << 90 88 95 84 >> #1
 67 Proj <== 64 << 68 71 6 77 83 90 92 >> #2 Memory: @BotPTR *+bot <idx=Bot>
 89 CastPI <== _ 69 << 90 97 >>
 78 ConL <== 0 << 84 90 >> #long[72623859790382856]
 90 StoreL <== 87 67 89 78 << 83 97 >> @rawptr:BotPTR <idx=Raw> Memory: @rawptr:BotPTR <idx=Raw>
 97 LoadB <== _ 90 89 <<>> @rawptr:BotPTR <idx=Raw> #byte