shithub: scc

--- a/cc2/Makefile

+++ b/cc2/Makefile

@@ -2,8 +2,9 @@

 include ../config.mk

-OBJS = main.o parser.o optm.o peep.o symbol.o node.o code.o\

-       arch/$(ARCH)/code.o arch/$(ARCH)/cgen.o arch/$(ARCH)/types.o

+OBJS = main.o parser.o peep.o symbol.o node.o code.o\

+       arch/$(ARCH)/code.o arch/$(ARCH)/cgen.o \

+       arch/$(ARCH)/types.o arch/$(ARCH)/optm.o

 all: cc2

--- /dev/null

+++ b/cc2/arch/amd64-sysv/optm.c

@@ -1,0 +1,9 @@

+#include "arch.h"

+#include "../../cc2.h"

+Node *

+optm(Node *np)

+{

+	return np;

+}

--- /dev/null

+++ b/cc2/arch/i386-sysv/optm.c

@@ -1,0 +1,9 @@

+#include "arch.h"

+#include "../../cc2.h"

+Node *

+optm(Node *np)

+{

+	return np;

+}

--- a/cc2/arch/qbe/arch.h

+++ b/cc2/arch/qbe/arch.h

@@ -131,5 +131,6 @@

 	ASTRUNCD,

 	ASJMP,

+	ASBRANCH,

 	ASRET,

};

--- a/cc2/arch/qbe/cgen.c

+++ b/cc2/arch/qbe/cgen.c

@@ -5,6 +5,12 @@

 #include "arch.h"

 #include "../../cc2.h"

+enum lflags {

+	FORCE = 1 << 0,

+	LOADL = 1 << 1,

+	LOADR = 1 << 2

+};

 enum sflags {

 	ISTMP  = 1,

 	ISCONS = 2

@@ -104,47 +110,58 @@

 	return np;

+/*

+ * load() load the address passed in a child of np in a temporary

+ * if it is not already in a temporay. It can be forced to load

+ * using the FORCE flag

+ */

 static Node *

-load(Node *np)

+load(Node *np, int flags)

 	int op;

-	Node *new = tmpnode(newnode(ONOP));

-	Type *tp = &np->type;

+	Type *tp;

+	Node *child;

-	new->left = np;

-	new->type = *tp;

+	child = (flags & LOADL) ? np->left : np->right;

+	tp = &child->type;

-	switch (tp->size) {

-	case 1:

-		op = ASLDB;

-		break;

-	case 2:

-		op = ASLDH;

-		break;

-	case 4:

-		op = (tp->flags & INTF) ? ASLDW : ASLDS;

-		break;

-	case 8:

-		op = (tp->flags & INTF) ? ASLDL : ASLDD;

-		break;

-	default:

-		abort();

+	if ((flags & FORCE) || !(child->flags & (ISTMP|ISCONS))) {

+		Node *new = tmpnode(newnode(OTMP));

+		new->type = *tp;

+		new->left = child;

+		switch (tp->size) {

+		case 1:

+			op = ASLDB;

+			break;

+		case 2:

+			op = ASLDH;

+			break;

+		case 4:

+			op = (tp->flags & INTF) ? ASLDW : ASLDS;

+			break;

+		case 8:

+			op = (tp->flags & INTF) ? ASLDL : ASLDD;

+			break;

+		default:

+			abort();

+		}

+		code(op, new, child, NULL);

+		child = new;

-	code(op, new, np, NULL);

-	return new;

+	return (flags & LOADL) ? (np->left = child) : (np->right = child);

 static Node *

-cast(Node *nd, Node *ns)

+cast(Node *nd)

 	Type *ts, *td;

-	Node *tmp;

+	Node *tmp, *ns;

 	int op, disint, sisint;

 	extern Type uint32type, int32type;

-	if ((ns->flags & (ISTMP|ISCONS)) == 0)

-		ns = nd->left = load(ns);

+	ns = load(nd, LOADL);

 	td = &nd->type;

 	ts = &ns->type;

 	disint = (td->flags & INTF) != 0;

@@ -193,7 +210,7 @@

 			tmp = tmpnode(newnode(ONOP));

 			tmp->type = (ts->flags&SIGNF) ? int32type : uint32type;

 			tmp->left = ns;

-			nd->left = ns = cast(tmp, ns);

+			nd->left = ns = cast(tmp);

 		case 4:

 			op = (td->size == 8) ? ASSWTOD : ASSWTOS;

 			break;

@@ -215,7 +232,7 @@

 Node *

 cgen(Node *np)

-	Node *l, *r;

+	Node *l, *r, *ifyes, *ifno, *next;

 	Symbol *sym;

 	Type *tp;

 	int op, off;

@@ -224,13 +241,7 @@

 	if (!np)

 		return NULL;

-	if (np->label) {

-		setlabel(np->label);

-		if (np->next == NULL) {

-			addstmt(newnode(ORET));

-			prevstmt();

-		}

-	}

+	setlabel(np->label);

 	l = cgen(np->left);

 	r = cgen(np->right);

 	tp = &np->type;

@@ -279,11 +290,7 @@

 			abort();

 		op = tbl[np->op] + off;

-		if ((l->flags & (ISTMP|ISCONS)) == 0)

-			l = np->left = load(l);

-		if ((r->flags & (ISTMP|ISCONS)) == 0)

-			r = np->right = load(r);

-		code(op, tmpnode(np), l, r);

+		code(op, tmpnode(np), load(np, LOADL), load(np, LOADR));

 		return np;

 	case ONOP:

 	case OBLOOP:

@@ -290,7 +297,7 @@

 	case OELOOP:

 		return NULL;

 	case OCAST:

-		return cast(np, l);

+		return cast(np);

 	case OADDR:

 		np->flags |= ISTMP;

 		np->op = OTMP;

@@ -297,7 +304,9 @@

 		np->u.sym = l->u.sym;

 		return np;

 	case OPTR:

-		np->left = load(load(l));

+		load(np, LOADL);

+		/* FIXME: The type of the loaded value is not np->type */

+		load(np, LOADL|FORCE);

 		return tmpnode(np);

 	case OCPL:

 	case OPAR:

@@ -333,14 +342,29 @@

 	case OOR:

 		abort();

 	case OBRANCH:

-		abort();

+		next = np->next;

+		l = load(np, LOADL);

+		if (next->label) {

+			sym = getsym(TMPSYM);

+			sym->kind = SLABEL;

+			next->label = sym;

+		}

+		ifyes = label(np->u.sym);

+		ifno = label(next->label);

+		op = ASBRANCH;

+		np = np->left;

+		goto emit_jump;

 	case OJMP:

-		code(ASJMP, np, NULL, NULL);

+		ifyes = label(np->u.sym);

+		op = ASJMP;

+		np = ifno = NULL;

+	emit_jump:

+		code(op, np, ifyes, ifno);

+		deltree(ifyes);

+		deltree(ifno);

 		return NULL;

 	case ORET:

-		if (l && (l->flags & (ISTMP|ISCONS)) == 0)

-			l = np->left = load(l);

-		code(ASRET, l, NULL, NULL);

+		code(ASRET, load(np, LOADL), NULL, NULL);

 		return NULL;

 	case OCASE:

 	case ODEFAULT:

--- a/cc2/arch/qbe/code.c

+++ b/cc2/arch/qbe/code.c

@@ -9,7 +9,8 @@

 #define ADDR_LEN (IDENTSIZ+64)

-static void binary(void), unary(void), store(void), jmp(void), ret(void);

+static void binary(void), unary(void), store(void), jmp(void), ret(void),

+            branch(void);

 static struct opdata {

 	void (*fun)(void);

@@ -122,6 +123,7 @@

 	[ASEXTS] = {.fun = unary, .txt = "exts", .letter = 'd'},

 	[ASSLTOS]= {.fun = unary, .txt = "truncd", .letter = 's'},

+	[ASBRANCH] = {.fun = branch},

 	[ASJMP]  = {.fun = jmp},

 	[ASRET]  = {.fun = ret},

};

@@ -403,7 +405,18 @@

 static void

 jmp(void)

-	printf("\t\tjmp\t%s\n", addr2txt(&pc->to));

+	printf("\t\tjmp\t%s\n", addr2txt(&pc->from1));

+}

+static void

+branch(void)

+{

+	char to[ADDR_LEN], from1[ADDR_LEN], from2[ADDR_LEN];

+	strcpy(to, addr2txt(&pc->to));

+	strcpy(from1, addr2txt(&pc->from1));

+	strcpy(from2, addr2txt(&pc->from2));

+	printf("\t\tjnz\t%s,%s,%s\n", to, from1, from2);

 void

--- /dev/null

+++ b/cc2/arch/qbe/optm.c

@@ -1,0 +1,67 @@

+#include <stddef.h>

+#include "arch.h"

+#include "../../cc2.h"

+Node *

+optm(Node *np)

+{

+	int op = np->op;

+	Node *p, *dst, *next = np->next;

+	Symbol *sym, *osym;

+	if (!next) {

+		/*

+		 * In QBE we need at the end of a basic block

+		 * a jump, so we have to ensure that the last

+		 * statement of the function is a ret, a jmp

+		 * or a branch. In the same way, QBE does

+		 * not accept labels at the end of a function

+		 * (ONOP is used for labels) so we have to add

+		 * a ret there, and in the case of branches

+		 * we need a label for the next statement

+		 */

+		if (op == ONOP || op == OBRANCH || (op != ORET && op != OJMP))

+			addstmt(newnode(ORET), KEEPCUR);

+		next = np->next;

+	}

+	switch (op) {

+	case ONOP:

+		if (next->op == ONOP) {

+			sym = np->u.sym;

+			osym = next->u.sym;

+			osym->id = sym->id;

+			osym->numid = sym->id;

+			osym->u.stmt = sym->u.stmt;

+			return NULL;

+		}

+		break;

+	case OBRANCH:

+		if (!next->label) {

+			sym = getsym(TMPSYM);

+			sym->kind = SLABEL;

+			next->label = sym;

+		}

+	case OJMP:

+		for (;;) {

+			dst = np->u.sym->u.stmt;

+			if (dst->op != OJMP)

+				break;

+			np->u.sym = dst->u.sym;

+		}

+		for (p = np->next; p; p = p->next) {

+			if (p == dst)

+				return NULL;

+			if (p->op == ONOP ||

+			    p->op == OBLOOP ||

+			    p->op == OELOOP) {

+				continue;

+			}

+			break;

+		}

+		break;

+	}

+	return np;

+}

--- /dev/null

+++ b/cc2/arch/z80/optm.c

@@ -1,0 +1,9 @@

+#include "arch.h"

+#include "../../cc2.h"

+Node *

+optm(Node *np)

+{

+	return np;

+}

--- a/cc2/cc2.h

+++ b/cc2/cc2.h

@@ -202,16 +202,18 @@

 extern void code(int op, Node *to, Node *from1, Node *from2);

 extern void defvar(Symbol *), defpar(Symbol *), defglobal(Symbol *);

 extern void setlabel(Symbol *sym);

+extern Node *label(Symbol *sym);

 /* node.c */

+#define SETCUR  1

+#define KEEPCUR 0

 extern void apply(Node *(*fun)(Node *));

 extern void cleannodes(void);

 extern void delnode(Node *np);

 extern void deltree(Node *np);

 extern Node *newnode(int op);

-extern Node *addstmt(Node *np);

-extern Node *prevstmt(void), *nextstmt(void);

+extern Node *addstmt(Node *np, int flags);

+extern Node *nextstmt(void);

 /* symbol.c */

 #define TMPSYM  0

--- a/cc2/code.c

+++ b/cc2/code.c

@@ -38,7 +38,6 @@

 		addr->kind = OCONST;

 		addr->u.i = np->u.i;

 		break;

-	case OJMP:

 	case OLABEL:

 		addr->kind = SLABEL;

 		goto symbol;

@@ -50,9 +49,18 @@

 	symbol:

 		addr->u.sym = np->u.sym;

 		break;

-	default:

-		abort();

+}

+Node *

+label(Symbol *sym)

+{

+	Node *np;

+	np = newnode(OLABEL);

+	np->u.sym = sym;

+	return np;

 void

--- a/cc2/node.c

+++ b/cc2/node.c

@@ -49,16 +49,20 @@

 Node *

-addstmt(Node *np)

+addstmt(Node *np, int flag)

+	if (curstmt)

+		np->next = curstmt->next;

+	np->prev = curstmt;

 	if (!curfun->u.stmt)

 		curfun->u.stmt = np;

 	else

 		curstmt->next = np;

-	np->next = NULL;

-	np->prev = curstmt;

-	curstmt = np;

+	if (flag == SETCUR)

+		curstmt = np;

 	return np;

@@ -84,12 +88,6 @@

 nextstmt(void)

 	return curstmt = curstmt->next;

-}

-Node *

-prevstmt(void)

-{

-	return curstmt = curstmt->prev;

 void

--- a/cc2/optm.c

+++ /dev/null

@@ -1,45 +1,0 @@

-#include <stddef.h>

-#include "arch.h"

-#include "cc2.h"

-Node *

-optm(Node *np)

-{

-	Node *p, *dst, *next = np->next;

-	Symbol *sym, *osym;

-	switch (np->op) {

-	case ONOP:

-		if (next && next->op == ONOP) {

-			sym = np->u.sym;

-			osym = next->u.sym;

-			osym->id = sym->id;

-			osym->numid = sym->id;

-			osym->u.stmt = sym->u.stmt;

-			return NULL;

-		}

-		break;

-	case OJMP:

-	case OBRANCH:

-		for (;;) {

-			dst = np->u.sym->u.stmt;

-			if (dst->op != OJMP)

-				break;

-			np->u.sym = dst->u.sym;

-		}

-		for (p = np->next; p; p = p->next) {

-			if (p == dst)

-				return NULL;

-			if (p->op == ONOP ||

-			    p->op == OBLOOP ||

-			    p->op == OELOOP) {

-				continue;

-			}

-			break;

-		}

-		break;

-	}

-	return np;

-}

--- a/cc2/parser.c

+++ b/cc2/parser.c

@@ -556,7 +556,7 @@

 	sym->kind = SLABEL;

 	sym->u.stmt = np;

 	np->label = sym;

-	addstmt(np);

+	addstmt(np, SETCUR);

 static void

@@ -570,7 +570,7 @@

 		deltree(np);

 		return;

-	addstmt(np);

+	addstmt(np, SETCUR);

 static void