use a new Ref type for registers

This might not be a good idea, the problem was that
many spurious registers would be added to the Bits
data-structures during compilation (and would
always remain 0).  However, doing the above
modification de-uniformizes the handling of temps
and regs, this makes the code longer and not
really nicer.  Also, additional Bits structures
are required to track the registers independently.

Overall this might be a bad idea to revert.

1 files changed, 57 insertions, 56 deletions

diff --git a/lisc/parse.c b/lisc/parse.c
index e1a1174..fe82cd8 100644
--- a/lisc/parse.c
+++ b/lisc/parse.c
@@ -4,8 +4,8 @@
 #include <ctype.h>
 
 enum {
-	NSym = 256,
-	NCons = 256,
+	NTmp = 256,
+	NCon = 256,
 };
 
 Ins insb[NIns], *curi;
@@ -48,7 +48,7 @@ typedef enum {
 	TL,
 
 	TNum,
-	TVar,
+	TTmp,
 	TLbl,
 	TAddr,
 	TEq,
@@ -68,10 +68,10 @@ static struct {
 } tokval;
 static int lnum;
 
-static Sym sym[NSym];
-static Cons cons[NCons];
-static int nsym;
-static int ncons;
+static Tmp tmp[NTmp];
+static Con con[NCon];
+static int ntmp;
+static int ncon;
 static Phi **plink;
 static Blk *bmap[NBlk+1];
 static Blk *curb;
@@ -150,7 +150,7 @@ lex()
 	case '=':
 		return TEq;
 	case '%':
-		t = TVar;
+		t = TTmp;
 		c = fgetc(inf);
 		goto Alpha;
 	case '@':
@@ -242,45 +242,45 @@ blocka()
 }
 
 static Ref
-varref(char *v)
+tmpref(char *v)
 {
-	int s;
-
-	for (s=0; s<nsym; s++)
-		if (strcmp(v, sym[s].name) == 0)
-			return SYM(s);
-	if (nsym++ >= NSym)
-		err("too many symbols");
-	strcpy(sym[s].name, v);
-	return SYM(s);
+	int t;
+
+	for (t=0; t<ntmp; t++)
+		if (strcmp(v, tmp[t].name) == 0)
+			return TMP(t);
+	if (ntmp++ >= NTmp)
+		err("too many temporaries");
+	strcpy(tmp[t].name, v);
+	return TMP(t);
 }
 
 static Ref
 parseref()
 {
-	Cons c;
+	Con c;
 	int i;
 
 	switch (next()) {
-	case TVar:
-		return varref(tokval.str);
+	case TTmp:
+		return tmpref(tokval.str);
 	case TNum:
-		c = (Cons){.type = CNum, .val = tokval.num};
+		c = (Con){.type = CNum, .val = tokval.num};
 		strcpy(c.label, "");
 	if (0) {
 	case TAddr:
-		c = (Cons){.type = CAddr, .val = 0};
+		c = (Con){.type = CAddr, .val = 0};
 		strcpy(c.label, tokval.str);
 	}
-		for (i=0; i<ncons; i++)
-			if (cons[i].type == c.type
-			&& cons[i].val == c.val
-			&& strcmp(cons[i].label, c.label) == 0)
-				return CONS(i);
-		if (ncons++ >= NCons)
+		for (i=0; i<ncon; i++)
+			if (con[i].type == c.type
+			&& con[i].val == c.val
+			&& strcmp(con[i].label, c.label) == 0)
+				return CON(i);
+		if (ncon++ >= NCon)
 			err("too many constants");
-		cons[i] = c;
-		return CONS(i);
+		con[i] = c;
+		return CON(i);
 	default:
 		return R;
 	}
@@ -358,7 +358,7 @@ parseline(PState ps)
 		err("label, instruction or jump expected");
 	case TEOF:
 		return PEnd;
-	case TVar:
+	case TTmp:
 		break;
 	case TLbl:
 		b = findblk(tokval.str);
@@ -400,14 +400,14 @@ parseline(PState ps)
 		closeblk();
 		return PLbl;
 	}
-	r = varref(tokval.str);
+	r = tmpref(tokval.str);
 	expect(TEq);
 	switch (next()) {
 	case TW:
-		sym[r.val].type = SWord;
+		tmp[r.val].type = TWord;
 		break;
 	case TL:
-		sym[r.val].type = SLong;
+		tmp[r.val].type = TLong;
 		break;
 	default:
 		err("class expected after =");
@@ -490,10 +490,10 @@ parsefn(FILE *f)
 	inf = f;
 	for (i=0; i<NBlk; i++)
 		bmap[i] = 0;
-	for (i=0; i<NSym; i++)
-		sym[i] = (Sym){.name = ""};
-	nsym = 0;
-	ncons = 0;
+	for (i=0; i<NTmp; i++)
+		tmp[i] = (Tmp){.name = ""};
+	ntmp = 1;
+	ncon = 0;
 	curi = insb;
 	curb = 0;
 	lnum = 1;
@@ -508,11 +508,12 @@ parsefn(FILE *f)
 		err("empty file");
 	if (curb->jmp.type == JXXX)
 		err("last block misses jump");
-	fn->sym = alloc(nsym * sizeof sym[0]);
-	memcpy(fn->sym, sym, nsym * sizeof sym[0]);
-	fn->cons = alloc(ncons * sizeof cons[0]);
-	memcpy(fn->cons, cons, ncons * sizeof cons[0]);
-	fn->nsym = nsym;
+	fn->tmp = alloc(ntmp * sizeof tmp[0]);
+	memcpy(fn->tmp, tmp, ntmp * sizeof tmp[0]);
+	fn->con = alloc(ncon * sizeof con[0]);
+	memcpy(fn->con, con, ncon * sizeof con[0]);
+	fn->ntmp = ntmp;
+	fn->ncon = ncon;
 	fn->nblk = nblk;
 	fn->rpo = 0;
 	return fn;
@@ -522,24 +523,24 @@ static char *
 printref(Ref r, Fn *fn, FILE *f)
 {
 	static char *ttoa[] = {
-		[SUndef] = "?",
-		[SWord] = "w",
-		[SLong] = "l",
+		[TUndef] = "?",
+		[TWord] = "w",
+		[TLong] = "l",
 	};
 
 	switch (r.type) {
-	case RSym:
-		fprintf(f, "%%%s", fn->sym[r.val].name);
-		return ttoa[fn->sym[r.val].type];
-	case RCons:
-		switch (fn->cons[r.val].type) {
+	case RTmp:
+		fprintf(f, "%%%s", fn->tmp[r.val].name);
+		return ttoa[fn->tmp[r.val].type];
+	case RCon:
+		switch (fn->con[r.val].type) {
 		case CAddr:
-			fprintf(f, "$%s", fn->cons[r.val].label);
-			if (fn->cons[r.val].val)
-				fprintf(f, "%+"PRIi64, fn->cons[r.val].val);
+			fprintf(f, "$%s", fn->con[r.val].label);
+			if (fn->con[r.val].val)
+				fprintf(f, "%+"PRIi64, fn->con[r.val].val);
 			break;
 		case CNum:
-			fprintf(f, "%"PRIi64, fn->cons[r.val].val);
+			fprintf(f, "%"PRIi64, fn->con[r.val].val);
 			break;
 		case CUndef:
 			diag("printref: invalid constant");