contrib/x86emu/x86emu.c

19  *  supporting documentation, and that the name of the authors not be used
20  *  in advertising or publicity pertaining to distribution of the software
22  *  representations about the suitability of this software for any purpose.
212  * Raise the specified interrupt to be handled before the execution of the
294  * Raise the specified interrupt to be handled before the execution of the
372  * Value of the default data segment
381  * decodings of addressing modes would have to set/clear a bit describing
382  * whether the access is relative to DS or SS.  That is the function of the
395  * 	ds/ss select (in absense of override)
397  * Each of the above 7 items are handled with a bit in the mode field.
631  * Return a pointer to the register given by the R/RM field of the
632  * modrm byte, for byte operands. Also enables the decoding of instructions.
679  * Return a pointer to the register given by the R/RM field of the
680  * modrm byte, for word operands.  Also enables the decoding of instructions.
727  * Return a pointer to the register given by the R/RM field of the
728  * modrm byte, for dword operands.  Also enables the decoding of instructions.
776  * Return a pointer to the register given by the R/RM field of the
778  * special case of segreg operands.  Also enables the decoding of instructions.
881  * Also enables the decoding of instructions.
1694 	int sf, of;
1697 	of = ACCESS_FLAG(F_OF) != 0;
1699 	common_jmp_near(emu, sf != of);
1709 	int sf, of;
1712 	of = ACCESS_FLAG(F_OF) != 0;
1714 	common_jmp_near(emu, sf == of);
1724 	int sf, of;
1727 	of = ACCESS_FLAG(F_OF) != 0;
1729 	common_jmp_near(emu, sf != of || ACCESS_FLAG(F_ZF));
1739 	int sf, of;
1742 	of = ACCESS_FLAG(F_OF) != 0;
1744 	common_jmp_near(emu, sf == of && !ACCESS_FLAG(F_ZF));
1770          * Weirdo special case instruction format.  Part of the opcode
1820          * Weirdo special case instruction format.  Part of the opcode
1838          * Weirdo special case instruction format.  Part of the opcode
1883          * Weirdo special case instruction format.  Part of the opcode
2486 	/* clear the lower bits of the flag register */
3155          * Yet another weirdo special case instruction format.  Part of
3204          * Yet another weirdo special case instruction format.  Part of
3896 	/* long, drawn out code follows.  Double switch for a total of 32
3941 	/* long, drawn out code follows.  Double switch for a total of 32
3990 	/* long, drawn out code follows.  Double switch for a total of 32
5896  * apparently required to emulate the setting of the OF and AF flag.
5898  * flag is the XOR of the top two bits of the carry chain for an
5903  * So, given the following table, which represents the addition of two
5916  * Construction of table for cout:
5926  * That represents alot of operations, but NO CHOICE....
5930  * The following table represents the subtraction of two bits, from
5943  * Construction of table for cout:
6722 	 * The new rotate is done mod 9, and given this, for a rotation of n
6761 		/* OVERFLOW is set *IFF* cnt==1, then it is the xor of CF and
6840 	 * The new rotate is done mod 9, and given this, for a rotation of n
6860 			 * 0..1 in any representation of the flags register
6889 		/* OVERFLOW is set *IFF* cnt==1, then it is the xor of CF and
6999 		 * of the result!!!                               */
7001 		/* OVERFLOW is set *IFF* s==1, then it is the xor of CF and
7008 		 * of the result!!!                               */
7034 		 * of the result!!!                               */
7060 		 * of the result!!!                               */
7097 		 * of the result!!!                               */
7099 		/* OVERFLOW is set *IFF* s==1, then it is the xor of the two
7104 		 * of the result!!!                               */
7128 		 * of the result!!!                               */
7152 		 * of the result!!!                               */