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
|
#include "Support/Statistic.h"
#include "Record.h"
#include "CodeEmitterGen.h"
bool CodeEmitterGen::run(std::ostream &o) {
std::vector<Record*> Insts;
const std::map<std::string, Record*> &Defs = Records.getDefs();
Record *Inst = Records.getClass("Instruction");
assert(Inst && "Couldn't find Instruction class!");
for (std::map<std::string, Record*>::const_iterator I = Defs.begin(),
E = Defs.end(); I != E; ++I)
if (I->second->isSubClassOf(Inst))
Insts.push_back(I->second);
std::string Namespace = "V9::";
std::string ClassName = "SparcV9CodeEmitter::";
//const std::string &Namespace = Inst->getValue("Namespace")->getName();
o << "unsigned " << ClassName
<< "getBinaryCodeForInstr(MachineInstr &MI) {\n"
<< " unsigned Value = 0;\n"
<< " DEBUG(std::cerr << MI);\n"
<< " switch (MI.getOpcode()) {\n";
for (std::vector<Record*>::iterator I = Insts.begin(), E = Insts.end();
I != E; ++I)
{
Record *R = *I;
o << " case " << Namespace << R->getName() << ": {\n"
<< " DEBUG(std::cerr << \"Emitting " << R->getName() << "\\n\");\n";
const RecordVal *InstVal = R->getValue("Inst");
if (!InstVal) {
std::cerr << "No 'Inst' record found in target description file!\n";
return true;
}
Init *InitVal = InstVal->getValue();
assert(dynamic_cast<BitsInit*>(InitVal) &&
"Can only handle undefined bits<> types!");
BitsInit *BI = (BitsInit*)InitVal;
unsigned Value = 0;
const std::vector<RecordVal> &Vals = R->getValues();
DEBUG(o << " // prefilling: ");
// Start by filling in fixed values...
for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1))) {
Value |= B->getValue() << (e-i-1);
DEBUG(o << B->getValue());
} else {
DEBUG(o << "0");
}
}
DEBUG(o << "\n");
DEBUG(o << " // " << *InstVal << "\n");
o << " Value = " << Value << "U;\n\n";
// Loop over all of the fields in the instruction adding in any
// contributions to this value (due to bit references).
//
unsigned op = 0;
std::map<const std::string,unsigned> OpOrder;
std::map<const std::string,bool> OpContinuous;
for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
if (Vals[i].getName() != "Inst" &&
!Vals[i].getValue()->isComplete() &&
/* ignore annul and predict bits since no one sets them yet */
Vals[i].getName() != "annul" &&
Vals[i].getName() != "predict")
{
o << " // op" << op << ": " << Vals[i].getName() << "\n"
<< " int64_t op" << op
<<" = getMachineOpValue(MI, MI.getOperand("<<op<<"));\n";
//<< " MachineOperand &op" << op <<" = MI.getOperand("<<op<<");\n";
OpOrder[Vals[i].getName()] = op++;
// Is the operand continuous? If so, we can just mask and OR it in
// instead of doing it bit-by-bit, saving a lot in runtime cost.
const BitsInit *InstInit = BI;
int beginBitInVar = -1, endBitInVar = -1,
beginBitInInst = -1, endBitInInst = -1;
bool continuous = true;
for (int bit = InstInit->getNumBits()-1; bit >= 0; --bit) {
if (VarBitInit *VBI =
dynamic_cast<VarBitInit*>(InstInit->getBit(bit))) {
TypedInit *TI = VBI->getVariable();
if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
// only process the current variable
if (VI->getName() != Vals[i].getName())
continue;
if (beginBitInVar == -1)
beginBitInVar = VBI->getBitNum();
if (endBitInVar == -1)
endBitInVar = VBI->getBitNum();
else {
if (endBitInVar == (int)VBI->getBitNum() + 1)
endBitInVar = VBI->getBitNum();
else {
continuous = false;
break;
}
}
if (beginBitInInst == -1)
beginBitInInst = bit;
if (endBitInInst == -1)
endBitInInst = bit;
else {
if (endBitInInst == bit + 1)
endBitInInst = bit;
else {
continuous = false;
break;
}
}
// maintain same distance between bits in field and bits in
// instruction. if the relative distances stay the same
// throughout,
if ((beginBitInVar - (int)VBI->getBitNum()) !=
(beginBitInInst - bit))
{
continuous = false;
break;
}
}
}
}
DEBUG(o << " // Var: begin = " << beginBitInVar
<< ", end = " << endBitInVar
<< "; Inst: begin = " << beginBitInInst
<< ", end = " << endBitInInst << "\n");
if (continuous) {
DEBUG(o << " // continuous: op" << OpOrder[Vals[i].getName()]
<< "\n");
// Mask off the right bits
// Low mask (ie. shift, if necessary)
if (endBitInVar != 0) {
o << " op" << OpOrder[Vals[i].getName()]
<< " >>= " << endBitInVar << ";\n";
beginBitInVar -= endBitInVar;
endBitInVar = 0;
}
// High mask
o << " op" << OpOrder[Vals[i].getName()]
<< " &= (1<<" << beginBitInVar+1 << ") - 1;\n";
// Shift the value to the correct place (according to place in instr)
if (endBitInInst != 0)
o << " op" << OpOrder[Vals[i].getName()]
<< " <<= " << endBitInInst << ";\n";
// Just OR in the result
o << " Value |= op" << OpOrder[Vals[i].getName()] << ";\n";
}
// otherwise, will be taken care of in the loop below using this value:
OpContinuous[Vals[i].getName()] = continuous;
}
}
for (unsigned f = 0, e = Vals.size(); f != e; ++f) {
if (Vals[f].getPrefix()) {
BitsInit *FieldInitializer = (BitsInit*)Vals[f].getValue();
// Scan through the field looking for bit initializers of the current
// variable...
for (int i = FieldInitializer->getNumBits()-1; i >= 0; --i) {
if (BitInit *BI=dynamic_cast<BitInit*>(FieldInitializer->getBit(i)))
{
DEBUG(o << " // bit init: f: " << f << ", i: " << i << "\n");
} else if (UnsetInit *UI =
dynamic_cast<UnsetInit*>(FieldInitializer->getBit(i))) {
DEBUG(o << " // unset init: f: " << f << ", i: " << i << "\n");
} else if (VarBitInit *VBI =
dynamic_cast<VarBitInit*>(FieldInitializer->getBit(i))) {
TypedInit *TI = VBI->getVariable();
if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
// If the bits of the field are laid out consecutively in the
// instruction, then instead of separately ORing in bits, just
// mask and shift the entire field for efficiency.
if (OpContinuous[VI->getName()]) {
// already taken care of in the loop above, thus there is no
// need to individually OR in the bits
// for debugging, output the regular version anyway, commented
DEBUG(o << " // Value |= getValueBit(op"
<< OpOrder[VI->getName()] << ", " << VBI->getBitNum()
<< ")" << " << " << i << ";\n");
} else {
o << " Value |= getValueBit(op" << OpOrder[VI->getName()]
<< ", " << VBI->getBitNum()
<< ")" << " << " << i << ";\n";
}
} else if (FieldInit *FI = dynamic_cast<FieldInit*>(TI)) {
// FIXME: implement this!
o << "FIELD INIT not implemented yet!\n";
} else {
o << "Error: UNIMPLEMENTED\n";
}
}
}
} else {
// ignore annul and predict bits since no one sets them yet
if (Vals[f].getName() == "annul" || Vals[f].getName() == "predict") {
o << " // found " << Vals[f].getName() << "\n";
}
}
}
o << " break;\n"
<< " }\n";
}
o << " default:\n"
<< " DEBUG(std::cerr << \"Not supported instr: \" << MI << \"\\n\");\n"
<< " abort();\n"
<< " }\n"
<< " return Value;\n"
<< "}\n";
return false;
}
|
