1
2 /*---------------------------------------------------------------*/
3 /*--- begin ir_match.c ---*/
4 /*---------------------------------------------------------------*/
5
6 /*
7 This file is part of Valgrind, a dynamic binary instrumentation
8 framework.
9
10 Copyright (C) 2004-2017 OpenWorks LLP
11 info@open-works.net
12
13 This program is free software; you can redistribute it and/or
14 modify it under the terms of the GNU General Public License as
15 published by the Free Software Foundation; either version 2 of the
16 License, or (at your option) any later version.
17
18 This program is distributed in the hope that it will be useful, but
19 WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
26 02110-1301, USA.
27
28 The GNU General Public License is contained in the file COPYING.
29
30 Neither the names of the U.S. Department of Energy nor the
31 University of California nor the names of its contributors may be
32 used to endorse or promote products derived from this software
33 without prior written permission.
34 */
35
36 /* Provides a facility for doing IR tree matching. */
37
38 #include "main_util.h"
39 #include "ir_match.h"
40
41
42 /* Assign a value to a binder. Checks for obvious stupidities. */
43
44 static
setBindee(MatchInfo * mi,Int n,const IRExpr * bindee)45 void setBindee ( MatchInfo* mi, Int n, const IRExpr* bindee )
46 {
47 if (n < 0 || n >= N_IRMATCH_BINDERS)
48 vpanic("setBindee: out of range index");
49 if (mi->bindee[n] != NULL)
50 vpanic("setBindee: bindee already set");
51 mi->bindee[n] = bindee;
52 }
53
54
55 /* This is the actual matching function, recursing over the pattern
56 and expression trees in the obvious way, and dumping any matches
57 found into 'mi'. */
58
59 static
matchWrk(MatchInfo * mi,const IRExpr * p,const IRExpr * e)60 Bool matchWrk ( MatchInfo* mi, const IRExpr* p/*attern*/,
61 const IRExpr* e/*xpr*/ )
62 {
63 switch (p->tag) {
64 case Iex_Binder: /* aha, what we were looking for. */
65 setBindee(mi, p->Iex.Binder.binder, e);
66 return True;
67 case Iex_Unop:
68 if (e->tag != Iex_Unop) return False;
69 if (p->Iex.Unop.op != e->Iex.Unop.op) return False;
70 if (!matchWrk(mi, p->Iex.Unop.arg, e->Iex.Unop.arg))
71 return False;
72 return True;
73 case Iex_Binop:
74 if (e->tag != Iex_Binop) return False;
75 if (p->Iex.Binop.op != e->Iex.Binop.op) return False;
76 if (!matchWrk(mi, p->Iex.Binop.arg1, e->Iex.Binop.arg1))
77 return False;
78 if (!matchWrk(mi, p->Iex.Binop.arg2, e->Iex.Binop.arg2))
79 return False;
80 return True;
81 case Iex_Load:
82 if (e->tag != Iex_Load) return False;
83 if (p->Iex.Load.end != e->Iex.Load.end) return False;
84 if (p->Iex.Load.ty != e->Iex.Load.ty) return False;
85 if (!matchWrk(mi, p->Iex.Load.addr, e->Iex.Load.addr))
86 return False;
87 return True;
88 case Iex_Const:
89 if (e->tag != Iex_Const) return False;
90 return eqIRConst(p->Iex.Const.con, e->Iex.Const.con);
91 default:
92 ppIRExpr(p);
93 vpanic("match");
94 }
95 }
96
97
98 /* Top level entry point to the matcher. */
99
matchIRExpr(MatchInfo * mi,const IRExpr * p,const IRExpr * e)100 Bool matchIRExpr ( MatchInfo* mi, const IRExpr* p/*attern*/,
101 const IRExpr* e/*xpr*/ )
102 {
103 Int i;
104 for (i = 0; i < N_IRMATCH_BINDERS; i++)
105 mi->bindee[i] = NULL;
106 return matchWrk(mi, p, e);
107 }
108
109
110
111 /*---------------------------------------------------------------*/
112 /*--- end ir_match.c ---*/
113 /*---------------------------------------------------------------*/
114