1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*************************************************************************
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * Copyright 2000, 2010 Oracle and/or its affiliates.
 *
 * OpenOffice.org - a multi-platform office productivity suite
 *
 * This file is part of OpenOffice.org.
 *
 * OpenOffice.org is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version 3
 * only, as published by the Free Software Foundation.
 *
 * OpenOffice.org is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License version 3 for more details
 * (a copy is included in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3 along with OpenOffice.org.  If not, see
 * <http://www.openoffice.org/license.html>
 * for a copy of the LGPLv3 License.
 *
 ************************************************************************/


// This is an implementation of the x86-64 ABI as described in 'System V
// Application Binary Interface, AMD64 Architecture Processor Supplement'
// (http://www.x86-64.org/documentation/abi-0.95.pdf)
//
// The code in this file is a modification of src/x86/ffi64.c from libffi
// (http://sources.redhat.com/libffi/) which is under the following license:

/* -----------------------------------------------------------------------
   ffi.c - Copyright (c) 2002  Bo Thorsen <bo@suse.de>

   x86-64 Foreign Function Interface

   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 CYGNUS SOLUTIONS 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.
   ----------------------------------------------------------------------- */

#include "sal/config.h"

#include "abi.hxx"

using namespace x86_64;

/* Register class used for passing given 64bit part of the argument.
   These represent classes as documented by the PS ABI, with the exception
   of SSESF, SSEDF classes, that are basically SSE class, just gcc will
   use SF or DFmode move instead of DImode to avoid reformating penalties.

   Similary we play games with INTEGERSI_CLASS to use cheaper SImode moves
   whenever possible (upper half does contain padding).
 */
enum x86_64_reg_class
{
    X86_64_NO_CLASS,
    X86_64_INTEGER_CLASS,
    X86_64_INTEGERSI_CLASS,
    X86_64_SSE_CLASS,
    X86_64_SSESF_CLASS,
    X86_64_SSEDF_CLASS,
    X86_64_SSEUP_CLASS,
    X86_64_X87_CLASS,
    X86_64_X87UP_CLASS,
    X86_64_MEMORY_CLASS
};

#define MAX_CLASSES 4

/* x86-64 register passing implementation.  See x86-64 ABI for details.  Goal
   of this code is to classify each 8bytes of incoming argument by the register
   class and assign registers accordingly.  */

/* Return the union class of CLASS1 and CLASS2.
   See the x86-64 PS ABI for details.  */

static enum x86_64_reg_class
merge_classes (enum x86_64_reg_class class1, enum x86_64_reg_class class2)
    throw ()
{
    /* Rule #1: If both classes are equal, this is the resulting class.  */
    if (class1 == class2)
        return class1;

    /* Rule #2: If one of the classes is NO_CLASS, the resulting class is
       the other class.  */
    if (class1 == X86_64_NO_CLASS)
        return class2;
    if (class2 == X86_64_NO_CLASS)
        return class1;

    /* Rule #3: If one of the classes is MEMORY, the result is MEMORY.  */
    if (class1 == X86_64_MEMORY_CLASS || class2 == X86_64_MEMORY_CLASS)
        return X86_64_MEMORY_CLASS;

    /* Rule #4: If one of the classes is INTEGER, the result is INTEGER.  */
    if ((class1 == X86_64_INTEGERSI_CLASS && class2 == X86_64_SSESF_CLASS)
            || (class2 == X86_64_INTEGERSI_CLASS && class1 == X86_64_SSESF_CLASS))
        return X86_64_INTEGERSI_CLASS;
    if (class1 == X86_64_INTEGER_CLASS || class1 == X86_64_INTEGERSI_CLASS
            || class2 == X86_64_INTEGER_CLASS || class2 == X86_64_INTEGERSI_CLASS)
        return X86_64_INTEGER_CLASS;

    /* Rule #5: If one of the classes is X87 or X87UP class, MEMORY is used.  */
    if (class1 == X86_64_X87_CLASS || class1 == X86_64_X87UP_CLASS
            || class2 == X86_64_X87_CLASS || class2 == X86_64_X87UP_CLASS)
        return X86_64_MEMORY_CLASS;

    /* Rule #6: Otherwise class SSE is used.  */
    return X86_64_SSE_CLASS;
}

/* Classify the argument of type TYPE and mode MODE.
   CLASSES will be filled by the register class used to pass each word
   of the operand.  The number of words is returned.  In case the parameter
   should be passed in memory, 0 is returned. As a special case for zero
   sized containers, classes[0] will be NO_CLASS and 1 is returned.

   See the x86-64 PS ABI for details.
*/
static int
classify_argument( typelib_TypeDescriptionReference *pTypeRef, enum x86_64_reg_class classes[], int byteOffset ) throw ()
{
    switch ( pTypeRef->eTypeClass )
    {
        case typelib_TypeClass_VOID:
            classes[0] = X86_64_NO_CLASS;
            return 1;
        case typelib_TypeClass_CHAR:
        case typelib_TypeClass_BOOLEAN:
        case typelib_TypeClass_BYTE:
        case typelib_TypeClass_SHORT:
        case typelib_TypeClass_UNSIGNED_SHORT:
        case typelib_TypeClass_LONG:
        case typelib_TypeClass_UNSIGNED_LONG:
        case typelib_TypeClass_HYPER:
        case typelib_TypeClass_UNSIGNED_HYPER:
        case typelib_TypeClass_ENUM:
            if ( ( byteOffset % 8 + pTypeRef->pType->nSize ) <= 4 )
                classes[0] = X86_64_INTEGERSI_CLASS;
            else
                classes[0] = X86_64_INTEGER_CLASS;
            return 1;
        case typelib_TypeClass_FLOAT:
            if ( ( byteOffset % 8 ) == 0 )
                classes[0] = X86_64_SSESF_CLASS;
            else
                classes[0] = X86_64_SSE_CLASS;
            return 1;
        case typelib_TypeClass_DOUBLE:
            classes[0] = X86_64_SSEDF_CLASS;
            return 1;
        /*case LONGDOUBLE:
            classes[0] = X86_64_X87_CLASS;
            classes[1] = X86_64_X87UP_CLASS;
            return 2;*/
        case typelib_TypeClass_STRING:
        case typelib_TypeClass_TYPE:
        case typelib_TypeClass_ANY:
        case typelib_TypeClass_TYPEDEF:
        case typelib_TypeClass_UNION:
        case typelib_TypeClass_SEQUENCE:
        case typelib_TypeClass_ARRAY:
        case typelib_TypeClass_INTERFACE:
            return 0;
        case typelib_TypeClass_STRUCT:
        case typelib_TypeClass_EXCEPTION:
            {
                typelib_TypeDescription * pTypeDescr = 0;
                TYPELIB_DANGER_GET( &pTypeDescr, pTypeRef );

                const int UNITS_PER_WORD = 8;
                int words = ( pTypeDescr->nSize + UNITS_PER_WORD - 1 ) / UNITS_PER_WORD;<--- Possible null pointer dereference: pTypeDescr
                enum x86_64_reg_class subclasses[MAX_CLASSES];

                /* If the struct is larger than 16 bytes, pass it on the stack.  */
                if ( pTypeDescr->nSize > 16 )<--- Possible null pointer dereference: pTypeDescr
                {
                    TYPELIB_DANGER_RELEASE( pTypeDescr );
                    return 0;
                }

                for ( int i = 0; i < words; i++ )
                    classes[i] = X86_64_NO_CLASS;

                const typelib_CompoundTypeDescription *pStruct = reinterpret_cast<const typelib_CompoundTypeDescription*>( pTypeDescr );

                /* Merge the fields of structure.  */
                for ( sal_Int32 nMember = 0; nMember < pStruct->nMembers; ++nMember )
                {
                    typelib_TypeDescriptionReference *pTypeInStruct = pStruct->ppTypeRefs[ nMember ];
                    int offset = byteOffset + pStruct->pMemberOffsets[ nMember ];

                    int num = classify_argument( pTypeInStruct, subclasses, offset );

                    if ( num == 0 )
                    {
                        TYPELIB_DANGER_RELEASE( pTypeDescr );
                        return 0;
                    }

                    for ( int i = 0; i < num; i++ )
                    {
                        int pos = offset / 8;
                        classes[i + pos] = merge_classes( subclasses[i], classes[i + pos] );
                    }
                }

                TYPELIB_DANGER_RELEASE( pTypeDescr );

                /* Final merger cleanup.  */
                for ( int i = 0; i < words; i++ )
                {
                    /* If one class is MEMORY, everything should be passed in
                       memory.  */
                    if ( classes[i] == X86_64_MEMORY_CLASS )
                        return 0;

                    /* The X86_64_SSEUP_CLASS should be always preceded by
                       X86_64_SSE_CLASS.  */
                    if ( classes[i] == X86_64_SSEUP_CLASS
                            && ( i == 0 || classes[i - 1] != X86_64_SSE_CLASS ) )
                        classes[i] = X86_64_SSE_CLASS;

                    /*  X86_64_X87UP_CLASS should be preceded by X86_64_X87_CLASS.  */
                    if ( classes[i] == X86_64_X87UP_CLASS
                            && ( i == 0 || classes[i - 1] != X86_64_X87_CLASS ) )
                        classes[i] = X86_64_SSE_CLASS;
                }
                return words;
            }

        default:
#if OSL_DEBUG_LEVEL > 1
            OSL_TRACE( "Unhandled case: pType->eTypeClass == %d", pTypeRef->eTypeClass );
#endif
            OSL_ASSERT(0);
    }
    return 0; /* Never reached.  */
}

/* Examine the argument and return set number of register required in each
   class.  Return 0 iff parameter should be passed in memory.  */
bool x86_64::examine_argument( typelib_TypeDescriptionReference *pTypeRef, bool bInReturn, int &nUsedGPR, int &nUsedSSE ) throw ()
{
    enum x86_64_reg_class classes[MAX_CLASSES];
    int n;

    n = classify_argument( pTypeRef, classes, 0 );

    if ( n == 0 )
        return false;

    nUsedGPR = 0;
    nUsedSSE = 0;
    for ( n--; n >= 0; n-- )
        switch ( classes[n] )
        {
            case X86_64_INTEGER_CLASS:
            case X86_64_INTEGERSI_CLASS:
                nUsedGPR++;
                break;
            case X86_64_SSE_CLASS:
            case X86_64_SSESF_CLASS:
            case X86_64_SSEDF_CLASS:
                nUsedSSE++;
                break;
            case X86_64_NO_CLASS:
            case X86_64_SSEUP_CLASS:
                break;
            case X86_64_X87_CLASS:
            case X86_64_X87UP_CLASS:
                if ( !bInReturn )
                    return false;
                break;
            default:
#if OSL_DEBUG_LEVEL > 1
            OSL_TRACE( "Unhandled case: classes[n] == %d", classes[n] );
#endif
            OSL_ASSERT(0);
        }
    return true;
}

bool x86_64::return_in_hidden_param( typelib_TypeDescriptionReference *pTypeRef ) throw ()
{
    int g, s;

    return examine_argument( pTypeRef, true, g, s ) == 0;
}

void x86_64::fill_struct( typelib_TypeDescriptionReference *pTypeRef, const sal_uInt64 *pGPR, const double *pSSE, void *pStruct ) throw ()
{
    enum x86_64_reg_class classes[MAX_CLASSES];
    int n;

    n = classify_argument( pTypeRef, classes, 0 );

    sal_uInt64 *pStructAlign = reinterpret_cast<sal_uInt64 *>( pStruct );
    for ( n--; n >= 0; n-- )
        switch ( classes[n] )
        {
            case X86_64_INTEGER_CLASS:
            case X86_64_INTEGERSI_CLASS:
                *pStructAlign++ = *pGPR++;
                break;
            case X86_64_SSE_CLASS:
            case X86_64_SSESF_CLASS:
            case X86_64_SSEDF_CLASS:
                *pStructAlign++ = *reinterpret_cast<const sal_uInt64 *>( pSSE++ );
                break;
            default:
                break;
        }
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */