// Generated Code for eaN (Included twice by "eagen.c")
// Copyright (C) 199x Landon Dyer, 2011 Reboot and Friends
// RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
-// Source Utilised with the Kind Permission of Landon Dyer
+// Source utilised with the kind permission of Landon Dyer
//
int eaNgen(WORD siz)
switch (amN)
{
- case DREG: // "Do nothing" - they're in the opword
+ // "Do nothing" - they're in the opword
+ case DREG:
case AREG:
case AIND:
case APOSTINC:
case AM_CCR:
case AM_SR:
case AM_NONE:
- break; // This is a performance hit, though
- case ADISP: // expr(An)
+ // This is a performance hit, though
+ break;
+ case ADISP:
+ // expr(An)
if (w)
- { // Just deposit it
+ {
+ // Just deposit it
if (tdb)
rmark(cursect, sloc, tdb, MWORD, NULL);
- if (v + 0x8000 >= 0x18000)
+ if ((v == 0) && optim_flags[OPT_INDIRECT_DISP])
+ {
+ // If expr is 0, size optimise the opcode.
+ // Generally the lower 6 bits of the opcode
+ // for expr(ax) are 101rrr where rrr=the
+ // number of the register, then followed by
+ // a word containing 'expr'. We need to change
+ // that to 010rrr.
+ if ((siz & 0x8000) == 0)
+ {
+ chptr_opcode[0] &= ((0xFFC7 >> 8) & 255); // mask off bits
+ chptr_opcode[1] &= 0xFFC7 & 255; // mask off bits
+ chptr_opcode[0] |= ((0x0010 >> 8) & 255); // slap in 010 bits
+ chptr_opcode[1] |= 0x0010 & 255; // slap in 010 bits
+ }
+ else
+ {
+ // Special case for move ea,ea:
+ // there are two ea fields there and
+ // we get a signal if it's the second ea field
+ // from m_ea - siz's 16th bit is set
+ chptr_opcode[0] &= ((0xFE3F >> 8) & 255); // mask off bits
+ chptr_opcode[1] &= 0xFE3F & 255; // mask off bits
+ chptr_opcode[0] |= ((0x0080 >> 8) & 255); // slap in 010 bits
+ chptr_opcode[1] |= 0x0080 & 255; // slap in 010 bits
+ }
+
+ if (sbra_flag)
+ warn("0(An) converted to (An)");
+
+ return OK;
+ }
+
+ if ((v + 0x8000) >= 0x18000)
return error(range_error);
D_word(v);
}
else
- { // Arrange for fixup later on
- fixup(FU_WORD|FU_SEXT, sloc, aNexpr);
+ {
+ // Arrange for fixup later on
+ AddFixup(FU_WORD|FU_SEXT, sloc, aNexpr);
D_word(0);
}
break;
case PCDISP:
if (w)
- { // Just deposit it
+ {
+ // Just deposit it
if ((aNexattr & TDB) == cursect)
v -= (VALUE)sloc;
else if ((aNexattr & TDB) != ABS)
D_word(v);
}
else
- { // Arrange for fixup later on
- fixup(FU_WORD|FU_SEXT|FU_PCREL, sloc, aNexpr);
+ {
+ // Arrange for fixup later on
+ AddFixup(FU_WORD|FU_SEXT|FU_PCREL, sloc, aNexpr);
D_word(0);
}
break;
case AINDEXED:
- w = (WORD)((aNixreg << 12) | aNixsiz); // Compute ixreg and size+scale
+ // Compute ixreg and size+scale
+ w = (WORD)((aNixreg << 12) | aNixsiz);
if (aNexattr & DEFINED)
- { // Deposit a byte...
+ {
+ // Deposit a byte...
if (tdb)
- return error(abs_error); // Can't mark bytes
+ // Can't mark bytes
+ return error(abs_error);
if (v + 0x80 >= 0x180)
return error(range_error);
D_word(w);
}
else
- { // Fixup the byte later
- fixup(FU_BYTE|FU_SEXT, sloc+1, aNexpr);
+ {
+ // Fixup the byte later
+ AddFixup(FU_BYTE|FU_SEXT, sloc+1, aNexpr);
D_word(w);
}
break;
case PCINDEXED:
- w = (WORD)((aNixreg << 12) | aNixsiz); // Compute ixreg and size+scale
+ // Compute ixreg and size+scale
+ w = (WORD)((aNixreg << 12) | aNixsiz);
if (aNexattr & DEFINED)
- { // Deposit a byte...
+ {
+ // Deposit a byte...
if ((aNexattr & TDB) == cursect)
v -= (VALUE)sloc;
else if ((aNexattr & TDB) != ABS)
if (v + 0x80 >= 0x100)
return error(range_error);
- w |= v & 0xff;
+ w |= v & 0xFF;
D_word(w);
}
else
- { // Fixup the byte later
- fixup(FU_WBYTE|FU_SEXT|FU_PCREL, sloc, aNexpr);
+ {
+ // Fixup the byte later
+ AddFixup(FU_WBYTE|FU_SEXT|FU_PCREL, sloc, aNexpr);
D_word(w);
}
}
else
{
- fixup(FU_BYTE|FU_SEXT, sloc+1, aNexpr);
+ AddFixup(FU_BYTE|FU_SEXT, sloc+1, aNexpr);
D_word(0);
}
}
else
{
- fixup(FU_WORD|FU_SEXT, sloc, aNexpr);
+ AddFixup(FU_WORD|FU_SEXT, sloc, aNexpr);
D_word(0);
}
}
else
{
- fixup(FU_LONG, sloc, aNexpr);
+ AddFixup(FU_LONG, sloc, aNexpr);
D_long(0);
}
break;
default:
- interror(1); // IMMED size problem
+ // IMMED size problem
+ interror(1);
}
break;
}
else
{
- fixup(FU_WORD|FU_SEXT, sloc, aNexpr);
+ AddFixup(FU_WORD|FU_SEXT, sloc, aNexpr);
D_word(0);
}
}
else
{
- fixup(FU_LONG, sloc, aNexpr);
+ AddFixup(FU_LONG, sloc, aNexpr);
D_long(0);
}
case PCMPRE:
return error("unsupported 68020 addressing mode");
default:
- interror(3); // Bad addressing mode in ea gen
+ // Bad addressing mode in ea gen
+ interror(3);
}
return OK;
#undef aNexpr
#undef aNixreg
#undef aNixsiz
+