| // 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; |
| |
| USED(ctxt); |
| for(i=0; i<20; i++) { |
| if(p == nil || p->as != AJMP || p->pcond == nil) |
| return p; |
| p = p->pcond; |
| } |
| return nil; |
| } |
| |
| Prog* |
| brloop(Link *ctxt, Prog *p) |
| { |
| int c; |
| Prog *q; |
| |
| USED(ctxt); |
| c = 0; |
| for(q = p; q != nil; q = q->pcond) { |
| if(q->as != AJMP || q->pcond == nil) |
| break; |
| c++; |
| if(c >= 5000) |
| return nil; |
| } |
| return q; |
| } |
| |
| static void |
| checkaddr(Link *ctxt, Prog *p, Addr *a) |
| { |
| // Check expected encoding, especially TYPE_CONST vs TYPE_ADDR. |
| switch(a->type) { |
| case TYPE_NONE: |
| return; |
| |
| case TYPE_BRANCH: |
| if(a->reg != 0 || a->index != 0 || a->scale != 0 || a->name != 0) |
| break; |
| return; |
| |
| case TYPE_TEXTSIZE: |
| if(a->reg != 0 || a->index != 0 || a->scale != 0 || a->name != 0) |
| break; |
| return; |
| |
| case TYPE_MEM: |
| //if(a->u.bits != 0) |
| // break; |
| return; |
| |
| case TYPE_CONST: |
| // TODO(rsc): After fixing SHRQ, check a->index != 0 too. |
| if(a->name != 0 || a->sym != 0 || a->reg != 0) { |
| ctxt->diag("argument %D is TYPE_CONST, should be TYPE_ADDR, in %P", a, p); |
| return; |
| } |
| if(a->reg != 0 || a->scale != 0 || a->name != 0 || a->sym != nil || a->u.bits != 0) |
| break; |
| return; |
| |
| case TYPE_FCONST: |
| case TYPE_SCONST: |
| if(a->reg != 0 || a->index != 0 || a->scale != 0 || a->name != 0 || a->offset != 0 || a->sym != nil) |
| break; |
| return; |
| |
| case TYPE_REG: |
| // TODO(rsc): After fixing PINSRQ, check a->offset != 0 too. |
| // TODO(rsc): After fixing SHRQ, check a->index != 0 too. |
| if(a->scale != 0 || a->name != 0 || a->sym != nil) |
| break; |
| return; |
| |
| case TYPE_ADDR: |
| if(a->u.bits != 0) |
| break; |
| if(a->reg == 0 && a->index == 0 && a->scale == 0 && a->name == 0 && a->sym == nil) |
| ctxt->diag("argument %D is TYPE_ADDR, should be TYPE_CONST, in %P", a, p); |
| return; |
| |
| case TYPE_SHIFT: |
| if(a->index != 0 || a->scale != 0 || a->name != 0 || a->sym != nil || a->u.bits != 0) |
| break; |
| return; |
| |
| case TYPE_REGREG: |
| if(a->index != 0 || a->scale != 0 || a->name != 0 || a->sym != nil || a->u.bits != 0) |
| break; |
| return; |
| |
| case TYPE_REGREG2: |
| return; |
| |
| case TYPE_INDIR: |
| // Expect sym and name to be set, nothing else. |
| // Technically more is allowed, but this is only used for *name(SB). |
| if(a->reg != 0 || a->index != 0 || a->scale != 0 || a->name == 0 || a->offset != 0 || a->sym == nil || a->u.bits != 0) |
| break; |
| return; |
| } |
| |
| ctxt->diag("invalid encoding for argument %D in %P", a, p); |
| } |
| |
| void |
| linkpatch(Link *ctxt, LSym *sym) |
| { |
| int32 c; |
| char *name; |
| Prog *p, *q; |
| |
| ctxt->cursym = sym; |
| |
| for(p = sym->text; p != nil; p = p->link) { |
| checkaddr(ctxt, p, &p->from); |
| checkaddr(ctxt, p, &p->from3); |
| checkaddr(ctxt, p, &p->to); |
| |
| if(ctxt->arch->progedit) |
| ctxt->arch->progedit(ctxt, p); |
| if(p->to.type != TYPE_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) { |
| name = "<nil>"; |
| if(p->to.sym) |
| name = p->to.sym->name; |
| ctxt->diag("branch out of range (%#ux)\n%P [%s]", c, p, name); |
| p->to.type = TYPE_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 == TYPE_BRANCH) |
| p->to.offset = p->pcond->pc; |
| } |
| } |
| } |