It turns out most of the thumb2 instructions are not allowed to touch SP. The semanti...
[llvm/avr.git] / lib / VMCore / Instruction.cpp
blobe19ad1c16f9e78e71ed3b0a06ed6fc2799577dd9
1 //===-- Instruction.cpp - Implement the Instruction class -----------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the Instruction class for the VMCore library.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Type.h"
15 #include "llvm/Instructions.h"
16 #include "llvm/Function.h"
17 #include "llvm/Constants.h"
18 #include "llvm/GlobalVariable.h"
19 #include "llvm/Support/CallSite.h"
20 #include "llvm/Support/LeakDetector.h"
21 using namespace llvm;
23 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
24 Instruction *InsertBefore)
25 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) {
26 // Make sure that we get added to a basicblock
27 LeakDetector::addGarbageObject(this);
29 // If requested, insert this instruction into a basic block...
30 if (InsertBefore) {
31 assert(InsertBefore->getParent() &&
32 "Instruction to insert before is not in a basic block!");
33 InsertBefore->getParent()->getInstList().insert(InsertBefore, this);
37 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
38 BasicBlock *InsertAtEnd)
39 : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) {
40 // Make sure that we get added to a basicblock
41 LeakDetector::addGarbageObject(this);
43 // append this instruction into the basic block
44 assert(InsertAtEnd && "Basic block to append to may not be NULL!");
45 InsertAtEnd->getInstList().push_back(this);
49 // Out of line virtual method, so the vtable, etc has a home.
50 Instruction::~Instruction() {
51 assert(Parent == 0 && "Instruction still linked in the program!");
55 void Instruction::setParent(BasicBlock *P) {
56 if (getParent()) {
57 if (!P) LeakDetector::addGarbageObject(this);
58 } else {
59 if (P) LeakDetector::removeGarbageObject(this);
62 Parent = P;
65 void Instruction::removeFromParent() {
66 getParent()->getInstList().remove(this);
69 void Instruction::eraseFromParent() {
70 getParent()->getInstList().erase(this);
73 /// insertBefore - Insert an unlinked instructions into a basic block
74 /// immediately before the specified instruction.
75 void Instruction::insertBefore(Instruction *InsertPos) {
76 InsertPos->getParent()->getInstList().insert(InsertPos, this);
79 /// insertAfter - Insert an unlinked instructions into a basic block
80 /// immediately after the specified instruction.
81 void Instruction::insertAfter(Instruction *InsertPos) {
82 InsertPos->getParent()->getInstList().insertAfter(InsertPos, this);
85 /// moveBefore - Unlink this instruction from its current basic block and
86 /// insert it into the basic block that MovePos lives in, right before
87 /// MovePos.
88 void Instruction::moveBefore(Instruction *MovePos) {
89 MovePos->getParent()->getInstList().splice(MovePos,getParent()->getInstList(),
90 this);
94 const char *Instruction::getOpcodeName(unsigned OpCode) {
95 switch (OpCode) {
96 // Terminators
97 case Ret: return "ret";
98 case Br: return "br";
99 case Switch: return "switch";
100 case Invoke: return "invoke";
101 case Unwind: return "unwind";
102 case Unreachable: return "unreachable";
104 // Standard binary operators...
105 case Add: return "add";
106 case FAdd: return "fadd";
107 case Sub: return "sub";
108 case FSub: return "fsub";
109 case Mul: return "mul";
110 case FMul: return "fmul";
111 case UDiv: return "udiv";
112 case SDiv: return "sdiv";
113 case FDiv: return "fdiv";
114 case URem: return "urem";
115 case SRem: return "srem";
116 case FRem: return "frem";
118 // Logical operators...
119 case And: return "and";
120 case Or : return "or";
121 case Xor: return "xor";
123 // Memory instructions...
124 case Malloc: return "malloc";
125 case Free: return "free";
126 case Alloca: return "alloca";
127 case Load: return "load";
128 case Store: return "store";
129 case GetElementPtr: return "getelementptr";
131 // Convert instructions...
132 case Trunc: return "trunc";
133 case ZExt: return "zext";
134 case SExt: return "sext";
135 case FPTrunc: return "fptrunc";
136 case FPExt: return "fpext";
137 case FPToUI: return "fptoui";
138 case FPToSI: return "fptosi";
139 case UIToFP: return "uitofp";
140 case SIToFP: return "sitofp";
141 case IntToPtr: return "inttoptr";
142 case PtrToInt: return "ptrtoint";
143 case BitCast: return "bitcast";
145 // Other instructions...
146 case ICmp: return "icmp";
147 case FCmp: return "fcmp";
148 case PHI: return "phi";
149 case Select: return "select";
150 case Call: return "call";
151 case Shl: return "shl";
152 case LShr: return "lshr";
153 case AShr: return "ashr";
154 case VAArg: return "va_arg";
155 case ExtractElement: return "extractelement";
156 case InsertElement: return "insertelement";
157 case ShuffleVector: return "shufflevector";
158 case ExtractValue: return "extractvalue";
159 case InsertValue: return "insertvalue";
161 default: return "<Invalid operator> ";
164 return 0;
167 /// isIdenticalTo - Return true if the specified instruction is exactly
168 /// identical to the current one. This means that all operands match and any
169 /// extra information (e.g. load is volatile) agree.
170 bool Instruction::isIdenticalTo(const Instruction *I) const {
171 if (getOpcode() != I->getOpcode() ||
172 getNumOperands() != I->getNumOperands() ||
173 getType() != I->getType())
174 return false;
176 // We have two instructions of identical opcode and #operands. Check to see
177 // if all operands are the same.
178 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
179 if (getOperand(i) != I->getOperand(i))
180 return false;
182 // Check special state that is a part of some instructions.
183 if (const LoadInst *LI = dyn_cast<LoadInst>(this))
184 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() &&
185 LI->getAlignment() == cast<LoadInst>(I)->getAlignment();
186 if (const StoreInst *SI = dyn_cast<StoreInst>(this))
187 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() &&
188 SI->getAlignment() == cast<StoreInst>(I)->getAlignment();
189 if (const CmpInst *CI = dyn_cast<CmpInst>(this))
190 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
191 if (const CallInst *CI = dyn_cast<CallInst>(this))
192 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() &&
193 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() &&
194 CI->getAttributes().getRawPointer() ==
195 cast<CallInst>(I)->getAttributes().getRawPointer();
196 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this))
197 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() &&
198 CI->getAttributes().getRawPointer() ==
199 cast<InvokeInst>(I)->getAttributes().getRawPointer();
200 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) {
201 if (IVI->getNumIndices() != cast<InsertValueInst>(I)->getNumIndices())
202 return false;
203 for (unsigned i = 0, e = IVI->getNumIndices(); i != e; ++i)
204 if (IVI->idx_begin()[i] != cast<InsertValueInst>(I)->idx_begin()[i])
205 return false;
206 return true;
208 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) {
209 if (EVI->getNumIndices() != cast<ExtractValueInst>(I)->getNumIndices())
210 return false;
211 for (unsigned i = 0, e = EVI->getNumIndices(); i != e; ++i)
212 if (EVI->idx_begin()[i] != cast<ExtractValueInst>(I)->idx_begin()[i])
213 return false;
214 return true;
217 return true;
220 // isSameOperationAs
221 // This should be kept in sync with isEquivalentOperation in
222 // lib/Transforms/IPO/MergeFunctions.cpp.
223 bool Instruction::isSameOperationAs(const Instruction *I) const {
224 if (getOpcode() != I->getOpcode() ||
225 getNumOperands() != I->getNumOperands() ||
226 getType() != I->getType())
227 return false;
229 // We have two instructions of identical opcode and #operands. Check to see
230 // if all operands are the same type
231 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
232 if (getOperand(i)->getType() != I->getOperand(i)->getType())
233 return false;
235 // Check special state that is a part of some instructions.
236 if (const LoadInst *LI = dyn_cast<LoadInst>(this))
237 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() &&
238 LI->getAlignment() == cast<LoadInst>(I)->getAlignment();
239 if (const StoreInst *SI = dyn_cast<StoreInst>(this))
240 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() &&
241 SI->getAlignment() == cast<StoreInst>(I)->getAlignment();
242 if (const CmpInst *CI = dyn_cast<CmpInst>(this))
243 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
244 if (const CallInst *CI = dyn_cast<CallInst>(this))
245 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() &&
246 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() &&
247 CI->getAttributes().getRawPointer() ==
248 cast<CallInst>(I)->getAttributes().getRawPointer();
249 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this))
250 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() &&
251 CI->getAttributes().getRawPointer() ==
252 cast<InvokeInst>(I)->getAttributes().getRawPointer();
253 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) {
254 if (IVI->getNumIndices() != cast<InsertValueInst>(I)->getNumIndices())
255 return false;
256 for (unsigned i = 0, e = IVI->getNumIndices(); i != e; ++i)
257 if (IVI->idx_begin()[i] != cast<InsertValueInst>(I)->idx_begin()[i])
258 return false;
259 return true;
261 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) {
262 if (EVI->getNumIndices() != cast<ExtractValueInst>(I)->getNumIndices())
263 return false;
264 for (unsigned i = 0, e = EVI->getNumIndices(); i != e; ++i)
265 if (EVI->idx_begin()[i] != cast<ExtractValueInst>(I)->idx_begin()[i])
266 return false;
267 return true;
270 return true;
273 /// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the
274 /// specified block. Note that PHI nodes are considered to evaluate their
275 /// operands in the corresponding predecessor block.
276 bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const {
277 for (use_const_iterator UI = use_begin(), E = use_end(); UI != E; ++UI) {
278 // PHI nodes uses values in the corresponding predecessor block. For other
279 // instructions, just check to see whether the parent of the use matches up.
280 const PHINode *PN = dyn_cast<PHINode>(*UI);
281 if (PN == 0) {
282 if (cast<Instruction>(*UI)->getParent() != BB)
283 return true;
284 continue;
287 if (PN->getIncomingBlock(UI) != BB)
288 return true;
290 return false;
293 /// mayReadFromMemory - Return true if this instruction may read memory.
295 bool Instruction::mayReadFromMemory() const {
296 switch (getOpcode()) {
297 default: return false;
298 case Instruction::Free:
299 case Instruction::VAArg:
300 case Instruction::Load:
301 return true;
302 case Instruction::Call:
303 return !cast<CallInst>(this)->doesNotAccessMemory();
304 case Instruction::Invoke:
305 return !cast<InvokeInst>(this)->doesNotAccessMemory();
306 case Instruction::Store:
307 return cast<StoreInst>(this)->isVolatile();
311 /// mayWriteToMemory - Return true if this instruction may modify memory.
313 bool Instruction::mayWriteToMemory() const {
314 switch (getOpcode()) {
315 default: return false;
316 case Instruction::Free:
317 case Instruction::Store:
318 case Instruction::VAArg:
319 return true;
320 case Instruction::Call:
321 return !cast<CallInst>(this)->onlyReadsMemory();
322 case Instruction::Invoke:
323 return !cast<InvokeInst>(this)->onlyReadsMemory();
324 case Instruction::Load:
325 return cast<LoadInst>(this)->isVolatile();
329 /// mayThrow - Return true if this instruction may throw an exception.
331 bool Instruction::mayThrow() const {
332 if (const CallInst *CI = dyn_cast<CallInst>(this))
333 return !CI->doesNotThrow();
334 return false;
337 /// isAssociative - Return true if the instruction is associative:
339 /// Associative operators satisfy: x op (y op z) === (x op y) op z
341 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
343 bool Instruction::isAssociative(unsigned Opcode, const Type *Ty) {
344 return Opcode == And || Opcode == Or || Opcode == Xor ||
345 Opcode == Add || Opcode == Mul;
348 /// isCommutative - Return true if the instruction is commutative:
350 /// Commutative operators satisfy: (x op y) === (y op x)
352 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
353 /// applied to any type.
355 bool Instruction::isCommutative(unsigned op) {
356 switch (op) {
357 case Add:
358 case FAdd:
359 case Mul:
360 case FMul:
361 case And:
362 case Or:
363 case Xor:
364 return true;
365 default:
366 return false;
370 bool Instruction::isSafeToSpeculativelyExecute() const {
371 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
372 if (Constant *C = dyn_cast<Constant>(getOperand(i)))
373 if (C->canTrap())
374 return false;
376 switch (getOpcode()) {
377 default:
378 return true;
379 case UDiv:
380 case URem: {
381 // x / y is undefined if y == 0, but calcuations like x / 3 are safe.
382 ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1));
383 return Op && !Op->isNullValue();
385 case SDiv:
386 case SRem: {
387 // x / y is undefined if y == 0, and might be undefined if y == -1,
388 // but calcuations like x / 3 are safe.
389 ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1));
390 return Op && !Op->isNullValue() && !Op->isAllOnesValue();
392 case Load: {
393 if (cast<LoadInst>(this)->isVolatile())
394 return false;
395 if (isa<AllocationInst>(getOperand(0)))
396 return true;
397 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(getOperand(0)))
398 return !GV->hasExternalWeakLinkage();
399 // FIXME: Handle cases involving GEPs. We have to be careful because
400 // a load of a out-of-bounds GEP has undefined behavior.
401 return false;
403 case Call:
404 return false; // The called function could have undefined behavior or
405 // side-effects.
406 // FIXME: We should special-case some intrinsics (bswap,
407 // overflow-checking arithmetic, etc.)
408 case VAArg:
409 case Alloca:
410 case Malloc:
411 case Invoke:
412 case PHI:
413 case Store:
414 case Free:
415 case Ret:
416 case Br:
417 case Switch:
418 case Unwind:
419 case Unreachable:
420 return false; // Misc instructions which have effects