zpu: wip - add pass to convert registers to stack slots
[llvm/zpu.git] / lib / VMCore / Instruction.cpp
blob05bed4c64316fa77e406ec96153c6ccd0c700bd0
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/Instruction.h"
15 #include "llvm/Type.h"
16 #include "llvm/Instructions.h"
17 #include "llvm/Constants.h"
18 #include "llvm/Module.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!");
52 if (hasMetadataHashEntry())
53 clearMetadataHashEntries();
57 void Instruction::setParent(BasicBlock *P) {
58 if (getParent()) {
59 if (!P) LeakDetector::addGarbageObject(this);
60 } else {
61 if (P) LeakDetector::removeGarbageObject(this);
64 Parent = P;
67 void Instruction::removeFromParent() {
68 getParent()->getInstList().remove(this);
71 void Instruction::eraseFromParent() {
72 getParent()->getInstList().erase(this);
75 /// insertBefore - Insert an unlinked instructions into a basic block
76 /// immediately before the specified instruction.
77 void Instruction::insertBefore(Instruction *InsertPos) {
78 InsertPos->getParent()->getInstList().insert(InsertPos, this);
81 /// insertAfter - Insert an unlinked instructions into a basic block
82 /// immediately after the specified instruction.
83 void Instruction::insertAfter(Instruction *InsertPos) {
84 InsertPos->getParent()->getInstList().insertAfter(InsertPos, this);
87 /// moveBefore - Unlink this instruction from its current basic block and
88 /// insert it into the basic block that MovePos lives in, right before
89 /// MovePos.
90 void Instruction::moveBefore(Instruction *MovePos) {
91 MovePos->getParent()->getInstList().splice(MovePos,getParent()->getInstList(),
92 this);
96 const char *Instruction::getOpcodeName(unsigned OpCode) {
97 switch (OpCode) {
98 // Terminators
99 case Ret: return "ret";
100 case Br: return "br";
101 case Switch: return "switch";
102 case IndirectBr: return "indirectbr";
103 case Invoke: return "invoke";
104 case Unwind: return "unwind";
105 case Unreachable: return "unreachable";
107 // Standard binary operators...
108 case Add: return "add";
109 case FAdd: return "fadd";
110 case Sub: return "sub";
111 case FSub: return "fsub";
112 case Mul: return "mul";
113 case FMul: return "fmul";
114 case UDiv: return "udiv";
115 case SDiv: return "sdiv";
116 case FDiv: return "fdiv";
117 case URem: return "urem";
118 case SRem: return "srem";
119 case FRem: return "frem";
121 // Logical operators...
122 case And: return "and";
123 case Or : return "or";
124 case Xor: return "xor";
126 // Memory instructions...
127 case Alloca: return "alloca";
128 case Load: return "load";
129 case Store: return "store";
130 case GetElementPtr: return "getelementptr";
132 // Convert instructions...
133 case Trunc: return "trunc";
134 case ZExt: return "zext";
135 case SExt: return "sext";
136 case FPTrunc: return "fptrunc";
137 case FPExt: return "fpext";
138 case FPToUI: return "fptoui";
139 case FPToSI: return "fptosi";
140 case UIToFP: return "uitofp";
141 case SIToFP: return "sitofp";
142 case IntToPtr: return "inttoptr";
143 case PtrToInt: return "ptrtoint";
144 case BitCast: return "bitcast";
146 // Other instructions...
147 case ICmp: return "icmp";
148 case FCmp: return "fcmp";
149 case PHI: return "phi";
150 case Select: return "select";
151 case Call: return "call";
152 case Shl: return "shl";
153 case LShr: return "lshr";
154 case AShr: return "ashr";
155 case VAArg: return "va_arg";
156 case ExtractElement: return "extractelement";
157 case InsertElement: return "insertelement";
158 case ShuffleVector: return "shufflevector";
159 case ExtractValue: return "extractvalue";
160 case InsertValue: return "insertvalue";
162 default: return "<Invalid operator> ";
165 return 0;
168 /// isIdenticalTo - Return true if the specified instruction is exactly
169 /// identical to the current one. This means that all operands match and any
170 /// extra information (e.g. load is volatile) agree.
171 bool Instruction::isIdenticalTo(const Instruction *I) const {
172 return isIdenticalToWhenDefined(I) &&
173 SubclassOptionalData == I->SubclassOptionalData;
176 /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it
177 /// ignores the SubclassOptionalData flags, which specify conditions
178 /// under which the instruction's result is undefined.
179 bool Instruction::isIdenticalToWhenDefined(const Instruction *I) const {
180 if (getOpcode() != I->getOpcode() ||
181 getNumOperands() != I->getNumOperands() ||
182 getType() != I->getType())
183 return false;
185 // We have two instructions of identical opcode and #operands. Check to see
186 // if all operands are the same.
187 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
188 if (getOperand(i) != I->getOperand(i))
189 return false;
191 // Check special state that is a part of some instructions.
192 if (const LoadInst *LI = dyn_cast<LoadInst>(this))
193 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() &&
194 LI->getAlignment() == cast<LoadInst>(I)->getAlignment();
195 if (const StoreInst *SI = dyn_cast<StoreInst>(this))
196 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() &&
197 SI->getAlignment() == cast<StoreInst>(I)->getAlignment();
198 if (const CmpInst *CI = dyn_cast<CmpInst>(this))
199 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
200 if (const CallInst *CI = dyn_cast<CallInst>(this))
201 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() &&
202 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() &&
203 CI->getAttributes().getRawPointer() ==
204 cast<CallInst>(I)->getAttributes().getRawPointer();
205 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this))
206 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() &&
207 CI->getAttributes().getRawPointer() ==
208 cast<InvokeInst>(I)->getAttributes().getRawPointer();
209 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) {
210 if (IVI->getNumIndices() != cast<InsertValueInst>(I)->getNumIndices())
211 return false;
212 for (unsigned i = 0, e = IVI->getNumIndices(); i != e; ++i)
213 if (IVI->idx_begin()[i] != cast<InsertValueInst>(I)->idx_begin()[i])
214 return false;
215 return true;
217 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) {
218 if (EVI->getNumIndices() != cast<ExtractValueInst>(I)->getNumIndices())
219 return false;
220 for (unsigned i = 0, e = EVI->getNumIndices(); i != e; ++i)
221 if (EVI->idx_begin()[i] != cast<ExtractValueInst>(I)->idx_begin()[i])
222 return false;
223 return true;
226 return true;
229 // isSameOperationAs
230 // This should be kept in sync with isEquivalentOperation in
231 // lib/Transforms/IPO/MergeFunctions.cpp.
232 bool Instruction::isSameOperationAs(const Instruction *I) const {
233 if (getOpcode() != I->getOpcode() ||
234 getNumOperands() != I->getNumOperands() ||
235 getType() != I->getType())
236 return false;
238 // We have two instructions of identical opcode and #operands. Check to see
239 // if all operands are the same type
240 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
241 if (getOperand(i)->getType() != I->getOperand(i)->getType())
242 return false;
244 // Check special state that is a part of some instructions.
245 if (const LoadInst *LI = dyn_cast<LoadInst>(this))
246 return LI->isVolatile() == cast<LoadInst>(I)->isVolatile() &&
247 LI->getAlignment() == cast<LoadInst>(I)->getAlignment();
248 if (const StoreInst *SI = dyn_cast<StoreInst>(this))
249 return SI->isVolatile() == cast<StoreInst>(I)->isVolatile() &&
250 SI->getAlignment() == cast<StoreInst>(I)->getAlignment();
251 if (const CmpInst *CI = dyn_cast<CmpInst>(this))
252 return CI->getPredicate() == cast<CmpInst>(I)->getPredicate();
253 if (const CallInst *CI = dyn_cast<CallInst>(this))
254 return CI->isTailCall() == cast<CallInst>(I)->isTailCall() &&
255 CI->getCallingConv() == cast<CallInst>(I)->getCallingConv() &&
256 CI->getAttributes().getRawPointer() ==
257 cast<CallInst>(I)->getAttributes().getRawPointer();
258 if (const InvokeInst *CI = dyn_cast<InvokeInst>(this))
259 return CI->getCallingConv() == cast<InvokeInst>(I)->getCallingConv() &&
260 CI->getAttributes().getRawPointer() ==
261 cast<InvokeInst>(I)->getAttributes().getRawPointer();
262 if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(this)) {
263 if (IVI->getNumIndices() != cast<InsertValueInst>(I)->getNumIndices())
264 return false;
265 for (unsigned i = 0, e = IVI->getNumIndices(); i != e; ++i)
266 if (IVI->idx_begin()[i] != cast<InsertValueInst>(I)->idx_begin()[i])
267 return false;
268 return true;
270 if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(this)) {
271 if (EVI->getNumIndices() != cast<ExtractValueInst>(I)->getNumIndices())
272 return false;
273 for (unsigned i = 0, e = EVI->getNumIndices(); i != e; ++i)
274 if (EVI->idx_begin()[i] != cast<ExtractValueInst>(I)->idx_begin()[i])
275 return false;
276 return true;
279 return true;
282 /// isUsedOutsideOfBlock - Return true if there are any uses of I outside of the
283 /// specified block. Note that PHI nodes are considered to evaluate their
284 /// operands in the corresponding predecessor block.
285 bool Instruction::isUsedOutsideOfBlock(const BasicBlock *BB) const {
286 for (const_use_iterator UI = use_begin(), E = use_end(); UI != E; ++UI) {
287 // PHI nodes uses values in the corresponding predecessor block. For other
288 // instructions, just check to see whether the parent of the use matches up.
289 const User *U = *UI;
290 const PHINode *PN = dyn_cast<PHINode>(U);
291 if (PN == 0) {
292 if (cast<Instruction>(U)->getParent() != BB)
293 return true;
294 continue;
297 if (PN->getIncomingBlock(UI) != BB)
298 return true;
300 return false;
303 /// mayReadFromMemory - Return true if this instruction may read memory.
305 bool Instruction::mayReadFromMemory() const {
306 switch (getOpcode()) {
307 default: return false;
308 case Instruction::VAArg:
309 case Instruction::Load:
310 return true;
311 case Instruction::Call:
312 return !cast<CallInst>(this)->doesNotAccessMemory();
313 case Instruction::Invoke:
314 return !cast<InvokeInst>(this)->doesNotAccessMemory();
315 case Instruction::Store:
316 return cast<StoreInst>(this)->isVolatile();
320 /// mayWriteToMemory - Return true if this instruction may modify memory.
322 bool Instruction::mayWriteToMemory() const {
323 switch (getOpcode()) {
324 default: return false;
325 case Instruction::Store:
326 case Instruction::VAArg:
327 return true;
328 case Instruction::Call:
329 return !cast<CallInst>(this)->onlyReadsMemory();
330 case Instruction::Invoke:
331 return !cast<InvokeInst>(this)->onlyReadsMemory();
332 case Instruction::Load:
333 return cast<LoadInst>(this)->isVolatile();
337 /// mayThrow - Return true if this instruction may throw an exception.
339 bool Instruction::mayThrow() const {
340 if (const CallInst *CI = dyn_cast<CallInst>(this))
341 return !CI->doesNotThrow();
342 return false;
345 /// isAssociative - Return true if the instruction is associative:
347 /// Associative operators satisfy: x op (y op z) === (x op y) op z
349 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative.
351 bool Instruction::isAssociative(unsigned Opcode, const Type *Ty) {
352 return Opcode == And || Opcode == Or || Opcode == Xor ||
353 Opcode == Add || Opcode == Mul;
356 /// isCommutative - Return true if the instruction is commutative:
358 /// Commutative operators satisfy: (x op y) === (y op x)
360 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
361 /// applied to any type.
363 bool Instruction::isCommutative(unsigned op) {
364 switch (op) {
365 case Add:
366 case FAdd:
367 case Mul:
368 case FMul:
369 case And:
370 case Or:
371 case Xor:
372 return true;
373 default:
374 return false;
378 bool Instruction::isSafeToSpeculativelyExecute() const {
379 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
380 if (Constant *C = dyn_cast<Constant>(getOperand(i)))
381 if (C->canTrap())
382 return false;
384 switch (getOpcode()) {
385 default:
386 return true;
387 case UDiv:
388 case URem: {
389 // x / y is undefined if y == 0, but calcuations like x / 3 are safe.
390 ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1));
391 return Op && !Op->isNullValue();
393 case SDiv:
394 case SRem: {
395 // x / y is undefined if y == 0, and might be undefined if y == -1,
396 // but calcuations like x / 3 are safe.
397 ConstantInt *Op = dyn_cast<ConstantInt>(getOperand(1));
398 return Op && !Op->isNullValue() && !Op->isAllOnesValue();
400 case Load: {
401 if (cast<LoadInst>(this)->isVolatile())
402 return false;
403 // Note that it is not safe to speculate into a malloc'd region because
404 // malloc may return null.
405 // It's also not safe to follow a bitcast, for example:
406 // bitcast i8* (alloca i8) to i32*
407 // would result in a 4-byte load from a 1-byte alloca.
408 Value *Op0 = getOperand(0);
409 if (GEPOperator *GEP = dyn_cast<GEPOperator>(Op0)) {
410 // TODO: it's safe to do this for any GEP with constant indices that
411 // compute inside the allocated type, but not for any inbounds gep.
412 if (GEP->hasAllZeroIndices())
413 Op0 = GEP->getPointerOperand();
415 if (isa<AllocaInst>(Op0))
416 return true;
417 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(getOperand(0)))
418 return !GV->hasExternalWeakLinkage();
419 return false;
421 case Call:
422 return false; // The called function could have undefined behavior or
423 // side-effects.
424 // FIXME: We should special-case some intrinsics (bswap,
425 // overflow-checking arithmetic, etc.)
426 case VAArg:
427 case Alloca:
428 case Invoke:
429 case PHI:
430 case Store:
431 case Ret:
432 case Br:
433 case IndirectBr:
434 case Switch:
435 case Unwind:
436 case Unreachable:
437 return false; // Misc instructions which have effects
441 Instruction *Instruction::clone() const {
442 Instruction *New = clone_impl();
443 New->SubclassOptionalData = SubclassOptionalData;
444 if (!hasMetadata())
445 return New;
447 // Otherwise, enumerate and copy over metadata from the old instruction to the
448 // new one.
449 SmallVector<std::pair<unsigned, MDNode*>, 4> TheMDs;
450 getAllMetadata(TheMDs);
451 for (unsigned i = 0, e = TheMDs.size(); i != e; ++i)
452 New->setMetadata(TheMDs[i].first, TheMDs[i].second);
453 return New;