/*------------------------------------------------------------------------- _fsget2args.c - Floating point library in optimized assembly for 8051 Copyright (c) 2004, Paul Stoffregen, paul@pjrc.com This library is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this library; see the file COPYING. If not, write to the Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. As a special exception, if you link this library with other files, some of which are compiled with SDCC, to produce an executable, this library does not by itself cause the resulting executable to be covered by the GNU General Public License. This exception does not however invalidate any other reasons why the executable file might be covered by the GNU General Public License. -------------------------------------------------------------------------*/ #define __SDCC_FLOAT_LIB #include #ifdef FLOAT_ASM_MCS51 static void dummy(void) __naked { // arg1: passed in a,b,dph,dpl // arg2: passed on stack __asm .globl fsgetargs fsgetargs: // extract the two inputs, placing them into: // sign exponent mantissa // ---- -------- -------- // a: sign_a exp_a r4/r3/r2 // b: sign_b exp_b r7/r6/r5 // mov r2, dpl mov r3, dph mov c, b.7 rlc a mov sign_a, c mov exp_a, a jz 00001$ setb b.7 00001$: mov r4, b // now extract the 2nd parameter from the stack mov a, sp add a, #249 mov r0, a mov a, @r0 mov r5, a inc r0 mov a, @r0 mov r6, a inc r0 mov b, @r0 inc r0 mov a, @r0 mov c, b.7 rlc a mov sign_b, c mov exp_b, a jz 00002$ setb b.7 00002$: mov r7, b ret __endasm; } #endif