Import sources from 2011-03-30 iso image

1 files changed, 416 insertions, 0 deletions

diff --git a/sys/src/cmd/vl/noop.c b/sys/src/cmd/vl/noop.c
new file mode 100755
index 000000000..337e947d3
--- /dev/null
+++ b/sys/src/cmd/vl/noop.c
@@ -0,0 +1,416 @@
+#include	"l.h"
+
+void
+noops(void)
+{
+	Prog *p, *p1, *q, *q1;
+	int o, curframe, curbecome, maxbecome;
+
+	/*
+	 * find leaf subroutines
+	 * become sizes
+	 * frame sizes
+	 * strip NOPs
+	 * expand RET
+	 * expand BECOME pseudo
+	 */
+
+	if(debug['v'])
+		Bprint(&bso, "%5.2f noops\n", cputime());
+	Bflush(&bso);
+
+	curframe = 0;
+	curbecome = 0;
+	maxbecome = 0;
+	curtext = 0;
+
+	q = P;
+	for(p = firstp; p != P; p = p->link) {
+
+		/* find out how much arg space is used in this TEXT */
+		if(p->to.type == D_OREG && p->to.reg == REGSP)
+			if(p->to.offset > curframe)
+				curframe = p->to.offset;
+
+		switch(p->as) {
+		case ATEXT:
+			if(curtext && curtext->from.sym) {
+				curtext->from.sym->frame = curframe;
+				curtext->from.sym->become = curbecome;
+				if(curbecome > maxbecome)
+					maxbecome = curbecome;
+			}
+			curframe = 0;
+			curbecome = 0;
+
+			p->mark |= LABEL|LEAF|SYNC;
+			if(p->link)
+				p->link->mark |= LABEL;
+			curtext = p;
+			break;
+
+		/* too hard, just leave alone */
+		case AMOVW:
+			if(p->to.type == D_FCREG ||
+			   p->to.type == D_MREG) {
+				p->mark |= LABEL|SYNC;
+				break;
+			}
+			if(p->from.type == D_FCREG ||
+			   p->from.type == D_MREG) {
+				p->mark |= LABEL|SYNC;
+				addnop(p);
+				addnop(p);
+				nop.mfrom.count += 2;
+				nop.mfrom.outof += 2;
+				break;
+			}
+			break;
+
+		/* too hard, just leave alone */
+		case ACASE:
+		case ASYSCALL:
+		case AWORD:
+		case ATLBWR:
+		case ATLBWI:
+		case ATLBP:
+		case ATLBR:
+			p->mark |= LABEL|SYNC;
+			break;
+
+		case ANOR:
+			if(p->to.type == D_REG && p->to.reg == REGZERO)
+				p->mark |= LABEL|SYNC;
+			break;
+
+		case ARET:
+			/* special form of RET is BECOME */
+			if(p->from.type == D_CONST)
+				if(p->from.offset > curbecome)
+					curbecome = p->from.offset;
+
+			if(p->link != P)
+				p->link->mark |= LABEL;
+			break;
+
+		case ANOP:
+			q1 = p->link;
+			q->link = q1;		/* q is non-nop */
+			q1->mark |= p->mark;
+			continue;
+
+		case ABCASE:
+			p->mark |= LABEL|SYNC;
+			goto dstlab;
+
+		case ABGEZAL:
+		case ABLTZAL:
+		case AJAL:
+			if(curtext != P)
+				curtext->mark &= ~LEAF;
+
+		case AJMP:
+		case ABEQ:
+		case ABGEZ:
+		case ABGTZ:
+		case ABLEZ:
+		case ABLTZ:
+		case ABNE:
+		case ABFPT:
+		case ABFPF:
+			p->mark |= BRANCH;
+
+		dstlab:
+			q1 = p->cond;
+			if(q1 != P) {
+				while(q1->as == ANOP) {
+					q1 = q1->link;
+					p->cond = q1;
+				}
+				if(!(q1->mark & LEAF))
+					q1->mark |= LABEL;
+			} else
+				p->mark |= LABEL;
+			q1 = p->link;
+			if(q1 != P)
+				q1->mark |= LABEL;
+			break;
+		}
+		q = p;
+	}
+
+	if(curtext && curtext->from.sym) {
+		curtext->from.sym->frame = curframe;
+		curtext->from.sym->become = curbecome;
+		if(curbecome > maxbecome)
+			maxbecome = curbecome;
+	}
+
+	if(debug['b'])
+		print("max become = %d\n", maxbecome);
+	xdefine("ALEFbecome", STEXT, maxbecome);
+
+	curtext = 0;
+	for(p = firstp; p != P; p = p->link) {
+		switch(p->as) {
+		case ATEXT:
+			curtext = p;
+			break;
+		case AJAL:
+			if(curtext != P && curtext->from.sym != S && curtext->to.offset >= 0) {
+				o = maxbecome - curtext->from.sym->frame;
+				if(o <= 0)
+					break;
+				/* calling a become or calling a variable */
+				if(p->to.sym == S || p->to.sym->become) {
+					curtext->to.offset += o;
+					if(debug['b']) {
+						curp = p;
+						print("%D calling %D increase %d\n",
+							&curtext->from, &p->to, o);
+					}
+				}
+			}
+			break;
+		}
+	}
+
+	for(p = firstp; p != P; p = p->link) {
+		o = p->as;
+		switch(o) {
+		case ATEXT:
+			curtext = p;
+			autosize = p->to.offset + 4;
+			if(autosize <= 4)
+			if(curtext->mark & LEAF) {
+				p->to.offset = -4;
+				autosize = 0;
+			}
+
+			q = p;
+			if(autosize) {
+				q = prg();
+				q->as = AADD;
+				q->line = p->line;
+				q->from.type = D_CONST;
+				q->from.offset = -autosize;
+				q->to.type = D_REG;
+				q->to.reg = REGSP;
+
+				q->link = p->link;
+				p->link = q;
+			} else
+			if(!(curtext->mark & LEAF)) {
+				if(debug['v'])
+					Bprint(&bso, "save suppressed in: %s\n",
+						curtext->from.sym->name);
+				Bflush(&bso);
+				curtext->mark |= LEAF;
+			}
+
+			if(curtext->mark & LEAF) {
+				if(curtext->from.sym)
+					curtext->from.sym->type = SLEAF;
+				break;
+			}
+
+			q1 = prg();
+			q1->as = AMOVW;
+			q1->line = p->line;
+			q1->from.type = D_REG;
+			q1->from.reg = REGLINK;
+			q1->to.type = D_OREG;
+			q1->from.offset = 0;
+			q1->to.reg = REGSP;
+
+			q1->link = q->link;
+			q->link = q1;
+			break;
+
+		case ARET:
+			nocache(p);
+			if(p->from.type == D_CONST)
+				goto become;
+			if(curtext->mark & LEAF) {
+				if(!autosize) {
+					p->as = AJMP;
+					p->from = zprg.from;
+					p->to.type = D_OREG;
+					p->to.offset = 0;
+					p->to.reg = REGLINK;
+					p->mark |= BRANCH;
+					break;
+				}
+
+				p->as = AADD;
+				p->from.type = D_CONST;
+				p->from.offset = autosize;
+				p->to.type = D_REG;
+				p->to.reg = REGSP;
+
+				q = prg();
+				q->as = AJMP;
+				q->line = p->line;
+				q->to.type = D_OREG;
+				q->to.offset = 0;
+				q->to.reg = REGLINK;
+				q->mark |= BRANCH;
+
+				q->link = p->link;
+				p->link = q;
+				break;
+			}
+			p->as = AMOVW;
+			p->from.type = D_OREG;
+			p->from.offset = 0;
+			p->from.reg = REGSP;
+			p->to.type = D_REG;
+			p->to.reg = 2;
+
+			q = p;
+			if(autosize) {
+				q = prg();
+				q->as = AADD;
+				q->line = p->line;
+				q->from.type = D_CONST;
+				q->from.offset = autosize;
+				q->to.type = D_REG;
+				q->to.reg = REGSP;
+
+				q->link = p->link;
+				p->link = q;
+			}
+
+			q1 = prg();
+			q1->as = AJMP;
+			q1->line = p->line;
+			q1->to.type = D_OREG;
+			q1->to.offset = 0;
+			q1->to.reg = 2;
+			q1->mark |= BRANCH;
+
+			q1->link = q->link;
+			q->link = q1;
+			break;
+
+		become:
+			if(curtext->mark & LEAF) {
+
+				q = prg();
+				q->line = p->line;
+				q->as = AJMP;
+				q->from = zprg.from;
+				q->to = p->to;
+				q->cond = p->cond;
+				q->link = p->link;
+				q->mark |= BRANCH;
+				p->link = q;
+
+				p->as = AADD;
+				p->from = zprg.from;
+				p->from.type = D_CONST;
+				p->from.offset = autosize;
+				p->to = zprg.to;
+				p->to.type = D_REG;
+				p->to.reg = REGSP;
+
+				break;
+			}
+			q = prg();
+			q->line = p->line;
+			q->as = AJMP;
+			q->from = zprg.from;
+			q->to = p->to;
+			q->cond = p->cond;
+			q->link = p->link;
+			q->mark |= BRANCH;
+			p->link = q;
+
+			q = prg();
+			q->line = p->line;
+			q->as = AADD;
+			q->from.type = D_CONST;
+			q->from.offset = autosize;
+			q->to.type = D_REG;
+			q->to.reg = REGSP;
+			q->link = p->link;
+			p->link = q;
+
+			p->as = AMOVW;
+			p->from = zprg.from;
+			p->from.type = D_OREG;
+			p->from.offset = 0;
+			p->from.reg = REGSP;
+			p->to = zprg.to;
+			p->to.type = D_REG;
+			p->to.reg = REGLINK;
+
+			break;
+		}
+	}
+
+	curtext = P;
+	q = P;		/* p - 1 */
+	q1 = firstp;	/* top of block */
+	o = 0;		/* count of instructions */
+	for(p = firstp; p != P; p = p1) {
+		p1 = p->link;
+		o++;
+		if(p->mark & NOSCHED){
+			if(q1 != p){
+				sched(q1, q);
+			}
+			for(; p != P; p = p->link){
+				if(!(p->mark & NOSCHED))
+					break;
+				q = p;
+			}
+			p1 = p;
+			q1 = p;
+			o = 0;
+			continue;
+		}
+		if(p->mark & (LABEL|SYNC)) {
+			if(q1 != p)
+				sched(q1, q);
+			q1 = p;
+			o = 1;
+		}
+		if(p->mark & (BRANCH|SYNC)) {
+			sched(q1, p);
+			q1 = p1;
+			o = 0;
+		}
+		if(o >= NSCHED) {
+			sched(q1, p);
+			q1 = p1;
+			o = 0;
+		}
+		q = p;
+	}
+}
+
+void
+addnop(Prog *p)
+{
+	Prog *q;
+
+	q = prg();
+	q->as = ANOR;
+	q->line = p->line;
+	q->from.type = D_REG;
+	q->from.reg = REGZERO;
+	q->to.type = D_REG;
+	q->to.reg = REGZERO;
+
+	q->link = p->link;
+	p->link = q;
+}
+
+void
+nocache(Prog *p)
+{
+	p->optab = 0;
+	p->from.class = 0;
+	p->to.class = 0;
+}