2 NetWinder Floating Point Emulator
3 (c) Rebel.COM, 1998,1999
5 Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 unsigned int readRegister(const unsigned int nReg)
25 /* Note: The CPU thinks it has dealt with the current instruction. As
26 a result the program counter has been advanced to the next
27 instruction, and points 4 bytes beyond the actual instruction
28 that caused the invalid instruction trap to occur. We adjust
29 for this in this routine. LDF/STF instructions with Rn = PC
30 depend on the PC being correct, as they use PC+8 in their
31 address calculations. */
32 unsigned int *userRegisters = GET_USERREG();
33 unsigned int val = userRegisters[nReg];
34 if (REG_PC == nReg) val -= 4;
39 void writeRegister(const unsigned int nReg, const unsigned int val)
41 unsigned int *userRegisters = GET_USERREG();
42 userRegisters[nReg] = val;
46 unsigned int readCPSR(void)
48 return(readRegister(REG_CPSR));
52 void writeCPSR(const unsigned int val)
54 writeRegister(REG_CPSR,val);
58 unsigned int readConditionCodes(void)
63 return(readCPSR() & CC_MASK);
68 void writeConditionCodes(const unsigned int val)
70 unsigned int *userRegisters = GET_USERREG();
73 * Operate directly on userRegisters since
74 * the CPSR may be the PC register itself.
76 rval = userRegisters[REG_CPSR] & ~CC_MASK;
77 userRegisters[REG_CPSR] = rval | (val & CC_MASK);
81 unsigned int readMemoryInt(unsigned int *pMem)