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Decimal constants can be undefined or high-z. 

Add the ability for decimal constants to undefined or high-z.
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Cary R 2007-09-17 10:08:07 -07:00 committed by Stephen Williams
parent 3cbe4f076e
commit 2e12dee658
1 changed files with 50 additions and 0 deletions
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@ -91,6 +91,7 @@ static void line_directive();
static void line_directive2();
static verinum*make_unsized_binary(const char*txt);
static verinum*make_undef_highz_dec(const char*txt);
static verinum*make_unsized_dec(const char*txt);
static verinum*make_unsized_octal(const char*txt);
static verinum*make_unsized_hex(const char*txt);
@ -282,6 +283,8 @@ W [ \t\b\f\r]+
\'[sS]?[dD][ \t]*[0-9][0-9_]* { yylval.number = make_unsized_dec(yytext);
return BASED_NUMBER; }
\'[sS]?[dD][ \t]*[xzXZ?]_* { yylval.number = make_undef_highz_dec(yytext);
return BASED_NUMBER; }
\'[sS]?[bB][ \t]*[0-1xzXZ_\?]+ { yylval.number = make_unsized_binary(yytext);
return BASED_NUMBER; }
\'[sS]?[oO][ \t]*[0-7xzXZ_\?]+ { yylval.number = make_unsized_octal(yytext);
@ -671,6 +674,53 @@ static int dec_buf_div2(char *buf)
return partial;
}
/* Support a single x, z or ? as a decimal constant (from 1364-2005). */
static verinum* make_undef_highz_dec(const char* ptr)
{
bool signed_flag = false;
assert(*ptr == '\'');
/* The number may have decorations of the form 'sd<code>,
possibly with space between the d and the <code>.
Also, the 's' is optional, and marks the number as signed. */
ptr += 1;
if (tolower(*ptr) == 's') {
signed_flag = true;
ptr += 1;
}
assert(tolower(*ptr) == 'd');
ptr += 1;
while (*ptr && ((*ptr == ' ') || (*ptr == '\t')))
ptr += 1;
/* Process the code. */
verinum::V* bits = new verinum::V[1];
switch (*ptr) {
case 'x':
case 'X':
bits[0] = verinum::Vx;
break;
case 'z':
case 'Z':
case '?':
bits[0] = verinum::Vz;
break;
default:
assert(0);
}
ptr += 1;
while (*ptr == '_') ptr += 1;
assert(*ptr == 0);
verinum*out = new verinum(bits, 1, false);
out->has_sign(signed_flag);
delete[]bits;
return out;
}
/*
* Making a decimal number is much easier then the other base numbers
* because there are no z or x values to worry about. It is much