Unaligned memory access with JDK

[Владимир Кемпик]

Hello
I was recently playing with a simple risc-v core running on an fpga and found the idk crashes on it.
It crashes with SIG_ILL : ILL_TRP, on a simple load from memory instruction.
So I figured the main issue is unaligned memory access MacroAssembler::stop() and that risc-v core was pretty simple and didn’t support unaligned memory access.
Here is what I found:

void MacroAssembler::stop(const char* msg) {
  const char * msg1 = ((uint64_t)msg) & ~0x07 + 0x08;
  BLOCK_COMMENT(msg1);
  illegal_instruction(Assembler::csr::time);
  emit_int64((uintptr_t)msg1);
}

and emit_64 is :
  void emit_int64( int64_t x)  { *((int64_t*) end()) = x; set_end(end() + sizeof(int64_t)); }

the problem is that the end() pointer is shared between emit_int64, emit_int32, emit_int8, etc, and non of them do care about natural memory alignment for processed types:

  void emit_int32(int32_t x) {
    address curr = end();
    *((int32_t*) curr) = x;
    set_end(curr + sizeof(int32_t));
  }

  void emit_int8(int8_t x1) {
    address curr = end();
    *((int8_t*)  curr++) = x1;
    set_end(curr);
  }

So my question is - risc-v cores without unaligned memory access support - are they supported by risc-v openjdk port ?