scc

commit 475fa03250d04142fb1aeb9635ffe7e3eac434c8
parent c3b8a3ef1ef7df8ae85b1d0b9061725a02c356dc
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Fri, 30 Jan 2026 15:44:17 +0100

cc1: Add support for float constant

Strtold already manages all the complexity of dealing with floating
point numbers.

Diffstat:
M
src/cmd/scc-cc/cc1/code.c
 | 
18
+++++++++++++++++-
M
src/cmd/scc-cc/cc1/fold.c
 | 
3
++-
M
src/cmd/scc-cc/cc1/lex.c
 | 
47
++++++++++++++++++++++++++++++++++++++++-------

3 files changed, 59 insertions(+), 9 deletions(-)
diff --git a/src/cmd/scc-cc/cc1/code.c b/src/cmd/scc-cc/cc1/code.c
@@ -215,6 +215,8 @@ emitvar(Symbol *sym)
 static void
 emitconst(Node *np)
 {
+	int n;
+	unsigned char *fp, *p;
 	Symbol *sym = np->sym;
 	Type *tp = np->type;
 	unsigned long long u;
@@ -226,9 +228,23 @@ emitconst(Node *np)
 		u = (tp->prop & TSIGNED) ? sym->u.i : sym->u.u;
 		fprintf(outfp,
 		        "#%c%llX",
-		        np->type->letter,
+		        tp->letter,
 		        u & ones(tp->size));
 		break;
+	case FLOAT:
+		fp = (char *) &sym->u.f;
+
+		if (tp == floattype)
+			n = sizeof(sym->u.f);
+		else if (tp == doubletype)
+			n = sizeof(sym->u.d);
+		else
+			n = sizeof(sym->u.ld);
+
+		fprintf(outfp, "#%c", tp->letter);
+		for (p = fp; p < &fp[n]; ++p)
+			fprintf(outfp, "%02X", *p);
+		break;
 	default:
 		abort();
 	}
diff --git a/src/cmd/scc-cc/cc1/fold.c b/src/cmd/scc-cc/cc1/fold.c
@@ -451,7 +451,8 @@ foldcast(Node *np, Node *l)
 		}
 		break;
 	case FLOAT:
-		/* FIXME: The cast can be from another float type */
+		if (oldtp->op == FLOAT)
+			return np;
 		aux.u.f = (oldtp->prop & TSIGNED) ? osym->u.i : osym->u.u;
 		break;
 	default:
diff --git a/src/cmd/scc-cc/cc1/lex.c b/src/cmd/scc-cc/cc1/lex.c
@@ -348,8 +348,9 @@ tok2str(void)
 }
 
 static Symbol *
-readint(char *s, int base, int sign, Symbol *sym)
+readint(int base, int sign, Symbol *sym)
 {
+	char *s = yytext;
 	Type *tp = sym->type;
 	struct limits *lim;
 	unsigned long long u, val, max;
@@ -402,7 +403,7 @@ overflow:
 }
 
 static int
-integer(char *s, int base)
+integer(int base)
 {
 	Type *tp;
 	Symbol *sym;
@@ -433,11 +434,11 @@ convert:
 	sym = newsym(NS_IDEN, NULL);
 	sym->type = tp;
 	sym->flags |= SCONSTANT;
-	yylval.sym = readint(s, base, sign, sym);
+	yylval.sym = readint(base, sign, sym);
 	return CONSTANT;
 }
 
-static char *
+static void
 digits(int base)
 {
 	char *p;
@@ -461,13 +462,15 @@ digits(int base)
 	}
 end:
 	input->p = p;
-	return yytext;
 }
 
 static int
 number(void)
 {
-	int base;
+	Type *tp;
+	Symbol *sym;
+	int ch, base;
+	long double ld;
 
 	if (*input->p != '0') {
 		base = 10;
@@ -479,8 +482,36 @@ number(void)
 			base = 8;
 		}
 	}
+	digits(base);
+
+	if (*input->p != '.')
+		return integer(base);
+
+	sym = newsym(NS_IDEN, NULL);
 
-	return integer(digits(base), base);
+	ld = strtold(input->begin, &input->p);
+	switch (toupper(*input->p)) {
+	case 'F':
+		++input->p;
+		tp = floattype;
+		sym->u.f = ld;
+		break;
+	case 'L':
+		++input->p;
+		tp = ldoubletype;
+		sym->u.ld = ld;
+		break;
+	default:
+		tp = doubletype;
+		sym->u.d = ld;
+		break;
+	}
+
+	tok2str();
+	sym->type = tp;
+	sym->flags |= SCONSTANT;
+	yylval.sym = sym;
+	return CONSTANT;
 }
 
 static int
@@ -792,6 +823,8 @@ dot(void)
 {
 	int c;
 
+	if (isdigit(*input->p))
+		return number();
 	if ((c = *input->p) != '.')
 		return '.';
 	if ((c = *++input->p) != '.')