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/* ppcbxx.h -- PowerPC Branch trick
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This file is part of the UPX executable compressor.
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Copyright (C) 1996-2004 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 1996-2004 Laszlo Molnar
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Copyright (C) 2004-2005 John F. Reiser
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UPX and the UCL library are free software; you can redistribute them
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and/or modify them under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of
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the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING.
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If not, write to the Free Software Foundation, Inc.,
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59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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Markus F.X.J. Oberhumer Laszlo Molnar
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<mfx@users.sourceforge.net> <ml1050@users.sourceforge.net>
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<jreiser@users.sourceforge.net>
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/*************************************************************************
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**************************************************************************/
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#define W_CTO 4 /* width of cto; must match stub/ppc_bxx.S */
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static int F(Filter *f)
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const unsigned addvalue = f->addvalue;
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const upx_byte *b = f->buf;
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const unsigned size = umin(f->buf_len, -(~0u<<(32 - (6+ W_CTO))));
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const unsigned size4 = size -4;
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unsigned calls = 0, noncalls = 0;
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unsigned lastnoncall = size, lastcall = 0;
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// find 26-2-W_CTO bits of displacements that contain no targets
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unsigned char buf[256];
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unsigned short wbuf[256];
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const size_t WW = (size_t)0 - (~(size_t)0) << W_CTO; // ???
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memset(wbuf, 0, sizeof(wbuf));
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memset(buf + WW, 1, 256 - WW);
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for (ic = 0; ic<=size4; ic+=4) if (COND(b,ic)) {
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unsigned const off = (int)(get_be32(b+ic)<<6) >>6;
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if (size <= (off & (~0u<<2))+ic) {
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buf[(~(~0u<<W_CTO)) & (off>>(26 - W_CTO))] |= 1;
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++wbuf[0xff&(off>>18)];
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if (getcto(f, buf) < 0) {
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if (0!=W_CTO) // FIXME: what is this ???
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const unsigned char cto8 = f->cto;
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const unsigned cto = (unsigned)f->cto << (24+2 - W_CTO);
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for (ic = 0; ic<=size4; ic+=4) if (COND(b,ic)) {
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unsigned const word = get_be32(b+ic);
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unsigned const off = (int)(word<<6) >>6;
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unsigned const jc = (off & (~0u<<2))+ic;
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// try to detect 'real' calls only
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set_be32(b+ic,(0xfc000003&word) | (jc+addvalue+cto));
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assert(0==W_CTO // FIXME: what is this ???
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|| (~(~0u<<W_CTO) & (word>>(24+2 - W_CTO))) != cto8); // this should not happen
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f->noncalls = noncalls;
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f->lastcall = lastcall;
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printf("\ncalls=%d noncalls=%d text_size=%x calltrickoffset=%x\n",
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calls,noncalls,size,cto8);
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/*************************************************************************
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**************************************************************************/
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static int U(Filter *f)
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upx_byte *b = f->buf;
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const unsigned size4 = umin(f->buf_len - 4, -(~0u<<(32 - (6+ W_CTO))));
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const unsigned addvalue = f->addvalue;
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for (ic = 0; ic<=size4; ic+=4) if (COND(b,ic)) {
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unsigned const word = get_be32(b+ic);
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if ((~(~0u<<W_CTO) & (word>>(24+2 - W_CTO))) == f->cto) {
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unsigned const jc = word & (~(~0u<<(26 - W_CTO)) & (~0u<<2));
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set_be32(b+ic, (0xfc000003&word)|(0x03fffffc&(jc-ic-addvalue)));
added
removed
src/filter/ppcbxx.h
