support for 68k style offset(register) expressions.

This commit is contained in:
Kelvin Sherlock 2014-12-28 12:30:18 -05:00
parent 6d3ba9430e
commit 231bd95bdc

View File

@ -246,6 +246,24 @@ expr(rhs) ::= expr(a) PIPE expr(b). { rhs = Token::Make(a.intValue | b.intValue)
expr(rhs) ::= expr(a) AMPAMP expr(b). { rhs = Token::Make(a.intValue && b.intValue); } expr(rhs) ::= expr(a) AMPAMP expr(b). { rhs = Token::Make(a.intValue && b.intValue); }
expr(rhs) ::= expr(a) PIPEPIPE expr(b). { rhs = Token::Make(a.intValue || b.intValue); } expr(rhs) ::= expr(a) PIPEPIPE expr(b). { rhs = Token::Make(a.intValue || b.intValue); }
// 68k assembly - offset(register)
// offset is a 16-bit quantity... this will
// handle 32-bit values or 16-bit.
expr(rhs) ::= unary(a) LPAREN register(b) RPAREN.
{
uint32_t offset = a.intValue;
uint32_t value = b.intValue;
// offset is 16-bits.
if (offset <= 0xffff)
{
if (offset & 0x8000)
offset |= 0xffff0000;
}
rhs = Token::Make(value + offset);
}
unary(rhs) ::= term(a). { rhs = a; } unary(rhs) ::= term(a). { rhs = a; }
unary(rhs) ::= PLUS unary(a). [BANG] { rhs = a; } unary(rhs) ::= PLUS unary(a). [BANG] { rhs = a; }
@ -254,13 +272,21 @@ unary(rhs) ::= TILDE unary(a). { rhs = Token::Make(~a.intValue); }
unary(rhs) ::= BANG unary(a). { rhs = Token::Make(!a.intValue); } unary(rhs) ::= BANG unary(a). { rhs = Token::Make(!a.intValue); }
unary(rhs) ::= STAR unary(a). [BANG] { rhs = Token::Make(Debug::ReadLong(a)); } unary(rhs) ::= STAR unary(a). [BANG] { rhs = Token::Make(Debug::ReadLong(a)); }
term(rhs) ::= LPAREN expr(a) RPAREN. { rhs = a; } term(rhs) ::= LPAREN expr(a) RPAREN. { rhs = a; }
term(rhs) ::= INTEGER(a). { rhs = a; } term(rhs) ::= INTEGER(a). { rhs = a; }
term(rhs) ::= DREGISTER(a). { rhs = Token::Make(cpuGetDReg(a)); } term(rhs) ::= register(a). { rhs = a; }
term(rhs) ::= AREGISTER(a). { rhs = Token::Make(cpuGetAReg(a)); }
term(rhs) ::= XREGISTER(a).
term(rhs) ::= IDENTIFIER(a).
{
// should throw/barf if undefined?
rhs = Token::Make(Debug::VariableGet(*a.stringValue));
}
register(rhs) ::= DREGISTER(a). { rhs = Token::Make(cpuGetDReg(a)); }
register(rhs) ::= AREGISTER(a). { rhs = Token::Make(cpuGetAReg(a)); }
register(rhs) ::= XREGISTER(a).
{ {
switch(a) switch(a)
{ {
@ -274,9 +300,3 @@ term(rhs) ::= XREGISTER(a).
rhs = Token::Make(0); rhs = Token::Make(0);
} }
} }
term(rhs) ::= IDENTIFIER(a).
{
// should throw/barf if undefined?
rhs = Token::Make(Debug::VariableGet(*a.stringValue));
}