pred_inst.hh revision 12616:4b463b4dc098 
1/*
2 * Copyright (c) 2010, 2012-2013 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2007-2008 The Florida State University
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Stephen Hines
41 */
42#ifndef __ARCH_ARM_INSTS_PREDINST_HH__
43#define __ARCH_ARM_INSTS_PREDINST_HH__
44
45#include "arch/arm/insts/static_inst.hh"
46#include "base/trace.hh"
47
48namespace ArmISA
49{
50static inline uint32_t
51rotate_imm(uint32_t immValue, uint32_t rotateValue)
52{
53    rotateValue &= 31;
54    return rotateValue == 0 ? immValue :
55        (immValue >> rotateValue) | (immValue << (32 - rotateValue));
56}
57
58static inline uint32_t
59modified_imm(uint8_t ctrlImm, uint8_t dataImm)
60{
61    uint32_t bigData = dataImm;
62    uint32_t bigCtrl = ctrlImm;
63    if (bigCtrl < 4) {
64        switch (bigCtrl) {
65          case 0:
66            return bigData;
67          case 1:
68            return bigData | (bigData << 16);
69          case 2:
70            return (bigData << 8) | (bigData << 24);
71          case 3:
72            return (bigData << 0) | (bigData << 8) |
73                   (bigData << 16) | (bigData << 24);
74        }
75    }
76    bigCtrl = (bigCtrl << 1) | ((bigData >> 7) & 0x1);
77    bigData |= (1 << 7);
78    return bigData << (32 - bigCtrl);
79}
80
81static inline uint64_t
82simd_modified_imm(bool op, uint8_t cmode, uint8_t data, bool &immValid,
83                  bool isAarch64 = false)
84{
85    uint64_t bigData = data;
86    immValid = true;
87    switch (cmode) {
88      case 0x0:
89      case 0x1:
90        bigData = (bigData << 0) | (bigData << 32);
91        break;
92      case 0x2:
93      case 0x3:
94        bigData = (bigData << 8) | (bigData << 40);
95        break;
96      case 0x4:
97      case 0x5:
98        bigData = (bigData << 16) | (bigData << 48);
99        break;
100      case 0x6:
101      case 0x7:
102        bigData = (bigData << 24) | (bigData << 56);
103        break;
104      case 0x8:
105      case 0x9:
106        bigData = (bigData << 0) | (bigData << 16) |
107                  (bigData << 32) | (bigData << 48);
108        break;
109      case 0xa:
110      case 0xb:
111        bigData = (bigData << 8) | (bigData << 24) |
112                  (bigData << 40) | (bigData << 56);
113        break;
114      case 0xc:
115        bigData = (0xffULL << 0) | (bigData << 8) |
116                  (0xffULL << 32) | (bigData << 40);
117        break;
118      case 0xd:
119        bigData = (0xffffULL << 0) | (bigData << 16) |
120                  (0xffffULL << 32) | (bigData << 48);
121        break;
122      case 0xe:
123        if (op) {
124            bigData = 0;
125            for (int i = 7; i >= 0; i--) {
126                if (bits(data, i)) {
127                    bigData |= (ULL(0xFF) << (i * 8));
128                }
129            }
130        } else {
131            bigData = (bigData << 0)  | (bigData << 8)  |
132                      (bigData << 16) | (bigData << 24) |
133                      (bigData << 32) | (bigData << 40) |
134                      (bigData << 48) | (bigData << 56);
135        }
136        break;
137      case 0xf:
138        {
139            uint64_t bVal = 0;
140            if (!op) {
141                bVal = bits(bigData, 6) ? (0x1F) : (0x20);
142                bigData = (bits(bigData, 5, 0) << 19) |
143                          (bVal << 25) | (bits(bigData, 7) << 31);
144                bigData |= (bigData << 32);
145                break;
146            } else if (isAarch64) {
147                bVal = bits(bigData, 6) ? (0x0FF) : (0x100);
148                bigData = (bits(bigData, 5, 0) << 48) |
149                          (bVal << 54) | (bits(bigData, 7) << 63);
150                break;
151            }
152        }
153        M5_FALLTHROUGH;
154      default:
155        immValid = false;
156        break;
157    }
158    return bigData;
159}
160
161static inline uint64_t
162vfp_modified_imm(uint8_t data, bool wide)
163{
164    uint64_t bigData = data;
165    uint64_t repData;
166    if (wide) {
167        repData = bits(data, 6) ? 0xFF : 0;
168        bigData = (bits(bigData, 5, 0) << 48) |
169                  (repData << 54) | (bits(~bigData, 6) << 62) |
170                  (bits(bigData, 7) << 63);
171    } else {
172        repData = bits(data, 6) ? 0x1F : 0;
173        bigData = (bits(bigData, 5, 0) << 19) |
174                  (repData << 25) | (bits(~bigData, 6) << 30) |
175                  (bits(bigData, 7) << 31);
176    }
177    return bigData;
178}
179
180
181/**
182 * Base class for predicated integer operations.
183 */
184class PredOp : public ArmStaticInst
185{
186  protected:
187
188    ConditionCode condCode;
189
190    /// Constructor
191    PredOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
192           ArmStaticInst(mnem, _machInst, __opClass)
193    {
194        if (machInst.aarch64)
195            condCode = COND_UC;
196        else if (machInst.itstateMask)
197            condCode = (ConditionCode)(uint8_t)machInst.itstateCond;
198        else
199            condCode = (ConditionCode)(unsigned)machInst.condCode;
200    }
201};
202
203/**
204 * Base class for predicated immediate operations.
205 */
206class PredImmOp : public PredOp
207{
208    protected:
209
210    uint32_t imm;
211    uint32_t rotated_imm;
212    uint32_t rotated_carry;
213    uint32_t rotate;
214
215    /// Constructor
216    PredImmOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
217              PredOp(mnem, _machInst, __opClass),
218              imm(machInst.imm), rotated_imm(0), rotated_carry(0),
219              rotate(machInst.rotate << 1)
220    {
221        rotated_imm = rotate_imm(imm, rotate);
222        if (rotate != 0)
223            rotated_carry = bits(rotated_imm, 31);
224    }
225
226    std::string generateDisassembly(
227            Addr pc, const SymbolTable *symtab) const override;
228};
229
230/**
231 * Base class for predicated integer operations.
232 */
233class PredIntOp : public PredOp
234{
235    protected:
236
237    uint32_t shift_size;
238    uint32_t shift;
239
240    /// Constructor
241    PredIntOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
242              PredOp(mnem, _machInst, __opClass),
243              shift_size(machInst.shiftSize), shift(machInst.shift)
244    {
245    }
246
247    std::string generateDisassembly(
248            Addr pc, const SymbolTable *symtab) const override;
249};
250
251class DataImmOp : public PredOp
252{
253  protected:
254    IntRegIndex dest, op1;
255    uint32_t imm;
256    // Whether the carry flag should be modified if that's an option for
257    // this instruction.
258    bool rotC;
259
260    DataImmOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
261              IntRegIndex _dest, IntRegIndex _op1, uint32_t _imm, bool _rotC) :
262        PredOp(mnem, _machInst, __opClass),
263        dest(_dest), op1(_op1), imm(_imm), rotC(_rotC)
264    {}
265
266    std::string generateDisassembly(
267            Addr pc, const SymbolTable *symtab) const override;
268};
269
270class DataRegOp : public PredOp
271{
272  protected:
273    IntRegIndex dest, op1, op2;
274    int32_t shiftAmt;
275    ArmShiftType shiftType;
276
277    DataRegOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
278              IntRegIndex _dest, IntRegIndex _op1, IntRegIndex _op2,
279              int32_t _shiftAmt, ArmShiftType _shiftType) :
280        PredOp(mnem, _machInst, __opClass),
281        dest(_dest), op1(_op1), op2(_op2),
282        shiftAmt(_shiftAmt), shiftType(_shiftType)
283    {}
284
285    std::string generateDisassembly(
286            Addr pc, const SymbolTable *symtab) const override;
287};
288
289class DataRegRegOp : public PredOp
290{
291  protected:
292    IntRegIndex dest, op1, op2, shift;
293    ArmShiftType shiftType;
294
295    DataRegRegOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass,
296                 IntRegIndex _dest, IntRegIndex _op1, IntRegIndex _op2,
297                 IntRegIndex _shift, ArmShiftType _shiftType) :
298        PredOp(mnem, _machInst, __opClass),
299        dest(_dest), op1(_op1), op2(_op2), shift(_shift),
300        shiftType(_shiftType)
301    {}
302
303    std::string generateDisassembly(
304            Addr pc, const SymbolTable *symtab) const override;
305};
306
307/**
308 * Base class for predicated macro-operations.
309 */
310class PredMacroOp : public PredOp
311{
312    protected:
313
314    uint32_t numMicroops;
315    StaticInstPtr * microOps;
316
317    /// Constructor
318    PredMacroOp(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
319                PredOp(mnem, _machInst, __opClass),
320                numMicroops(0), microOps(nullptr)
321    {
322        // We rely on the subclasses of this object to handle the
323        // initialization of the micro-operations, since they are
324        // all of variable length
325        flags[IsMacroop] = true;
326    }
327
328    ~PredMacroOp()
329    {
330        if (numMicroops)
331            delete [] microOps;
332    }
333
334    StaticInstPtr
335    fetchMicroop(MicroPC microPC) const override
336    {
337        assert(microPC < numMicroops);
338        return microOps[microPC];
339    }
340
341    Fault
342    execute(ExecContext *, Trace::InstRecord *) const override
343    {
344        panic("Execute method called when it shouldn't!");
345    }
346
347    std::string generateDisassembly(
348            Addr pc, const SymbolTable *symtab) const override;
349};
350
351/**
352 * Base class for predicated micro-operations.
353 */
354class PredMicroop : public PredOp
355{
356    /// Constructor
357    PredMicroop(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
358                PredOp(mnem, _machInst, __opClass)
359    {
360        flags[IsMicroop] = true;
361    }
362
363    void
364    advancePC(PCState &pcState) const
365    {
366        if (flags[IsLastMicroop])
367            pcState.uEnd();
368        else
369            pcState.uAdvance();
370    }
371};
372}
373
374#endif //__ARCH_ARM_INSTS_PREDINST_HH__
375