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diff --git a/src/liblink/pass.c b/src/liblink/pass.c
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+// Inferno utils/6l/pass.c
+// http://code.google.com/p/inferno-os/source/browse/utils/6l/pass.c
+//
+// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
+// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+// Portions Copyright © 1997-1999 Vita Nuova Limited
+// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+// Portions Copyright © 2004,2006 Bruce Ellis
+// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+// Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+// Code and data passes.
+
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <link.h>
+
+Prog*
+brchain(Link *ctxt, Prog *p)
+{
+ int i;
+
+ for(i=0; i<20; i++) {
+ if(p == nil || p->as != ctxt->arch->AJMP)
+ return p;
+ p = p->pcond;
+ }
+ return nil;
+}
+
+Prog*
+brloop(Link *ctxt, Prog *p)
+{
+ int c;
+ Prog *q;
+
+ c = 0;
+ for(q = p; q != nil; q = q->pcond) {
+ if(q->as != ctxt->arch->AJMP)
+ break;
+ c++;
+ if(c >= 5000)
+ return nil;
+ }
+ return q;
+}
+
+void
+linkpatch(Link *ctxt, LSym *sym)
+{
+ int32 c;
+ Prog *p, *q;
+
+ ctxt->cursym = sym;
+
+ for(p = sym->text; p != nil; p = p->link) {
+ if(ctxt->arch->progedit)
+ ctxt->arch->progedit(ctxt, p);
+ if(p->to.type != ctxt->arch->D_BRANCH)
+ continue;
+ if(p->to.u.branch != nil) {
+ // TODO: Remove to.u.branch in favor of p->pcond.
+ p->pcond = p->to.u.branch;
+ continue;
+ }
+ if(p->to.sym != nil)
+ continue;
+ c = p->to.offset;
+ for(q = sym->text; q != nil;) {
+ if(c == q->pc)
+ break;
+ if(q->forwd != nil && c >= q->forwd->pc)
+ q = q->forwd;
+ else
+ q = q->link;
+ }
+ if(q == nil) {
+ ctxt->diag("branch out of range (%#ux)\n%P [%s]",
+ c, p, p->to.sym ? p->to.sym->name : "<nil>");
+ p->to.type = ctxt->arch->D_NONE;
+ }
+ p->to.u.branch = q;
+ p->pcond = q;
+ }
+
+ for(p = sym->text; p != nil; p = p->link) {
+ p->mark = 0; /* initialization for follow */
+ if(p->pcond != nil) {
+ p->pcond = brloop(ctxt, p->pcond);
+ if(p->pcond != nil)
+ if(p->to.type == ctxt->arch->D_BRANCH)
+ p->to.offset = p->pcond->pc;
+ }
+ }
+}