core/insn_push_reg.v

   1 `define INSN_PUSH_reg           9'b011xx0101
   2
   3 `ifdef EXECUTE
   4         `INSN_PUSH_reg: begin   /* PUSH is 16 cycles! */
   5                 case (cycle)
   6                 0:      case (opcode[5:4])
   7                         `INSN_stack_AF: `EXEC_WRITE(`_SP - 1, `_A)
   8                         `INSN_stack_BC: `EXEC_WRITE(`_SP - 1, `_B)
   9                         `INSN_stack_DE: `EXEC_WRITE(`_SP - 1, `_D)
  10                         `INSN_stack_HL: `EXEC_WRITE(`_SP - 1, `_H)
  11                         endcase
  12                 1:      case (opcode[5:4])
  13                         `INSN_stack_AF: `EXEC_WRITE(`_SP - 2, `_F)
  14                         `INSN_stack_BC: `EXEC_WRITE(`_SP - 2, `_C)
  15                         `INSN_stack_DE: `EXEC_WRITE(`_SP - 2, `_E)
  16                         `INSN_stack_HL: `EXEC_WRITE(`_SP - 2, `_L)
  17                         endcase
  18                 2:      begin /* Twiddle thumbs. */ end
  19                 3:      begin
  20                                 `EXEC_NEWCYCLE
  21                                 `EXEC_INC_PC
  22                         end
  23                 endcase
  24         end
  25 `endif
  26
  27 `ifdef WRITEBACK
  28         `INSN_PUSH_reg: begin   /* PUSH is 16 cycles! */
  29                 case (cycle)
  30                 0:      begin /* type F */ end
  31                 1:      begin /* type F */ end
  32                 2:      begin /* type F */ end
  33                 3:      `_SP <= `_SP - 2;
  34                 endcase
  35         end
  36 `endif