+ // We have an aliasing problem here, because a couple of differenct cases end up here:
+ // (a0), 0(a0,d0), (-288,a0,d0.l) can be easily detected and parsed.
+ // But what about (160*150)+4(A1)? With the old scheme, i.e. skip past the left parenthesis and try to parse the inside
+ // tokens will only parse (160*150) and everything else is assumed that it's part of the ea, i.e. +4(a1). This would produce
+ // an error since the parser would expect (a1). The way to work around this used to be to wrap all the displacement in
+ // parenthesis, ((160*150)+4)(a1). But that's something the user really doesn't want to think about.
+ // What we can do is to peek ahead in the token stream and see if we have something that reminds of an expression
+ // (i.e. no register tokens or commas) until we hit an open parenthesis plus a register (parenthesis balance during the scan
+ // has to be maintained of course, otherwise we might be led into false conclusions).
+ TOKEN *look_ahead = tok;
+ int parenthesis_level = 1; // We count the opening parenthesis so we're not at level 0
+ int this_is_an_expression = 0;
+ while (1)
+ {
+ if (*look_ahead == EOL)
+ {
+ // Something really bad happened, abort
+ return error("reached end of line while parsing expression");
+ }
+ if (*look_ahead == '(')
+ {
+ if (parenthesis_level == 0)
+ {
+ if (look_ahead[1] == EOL)
+ {
+ return error("reached end of line while parsing expression");
+ }
+ if ((look_ahead[1] >= REG68_A0 && look_ahead[1] <= REG68_A7) || look_ahead[1] == REG68_PC)
+ {
+ tok--; // Rewind token pointer to start of parenthesis
+ this_is_an_expression = 1;
+ break;
+ }
+ }
+ parenthesis_level++;
+ look_ahead++;
+ continue;
+ }
+ if (*look_ahead == ',' || (*look_ahead >= REG68_A0 && *look_ahead <= REG68_A7))
+ {
+ // Nope, this is a different case, abort
+ break;
+ }
+ if (*look_ahead == ')')
+ {
+ parenthesis_level--;
+ if (parenthesis_level < 0) return error("unbalanced parenthesis in expression");
+ look_ahead++;
+ continue;
+ }
+ if (*look_ahead == ACONST||*look_ahead==FCONST)
+ {
+ look_ahead += 3; // Skip all the data associated with ACONST
+ continue;
+ }
+
+ look_ahead++;
+ }
+
projects / rmac / blobdiff