1 //===-- Attribute.cpp - Implement AttributesList -------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Attribute, AttributeImpl, AttrBuilder,
11 // AttributeSetImpl, and AttributeSet classes.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Attributes.h"
16 #include "AttributeImpl.h"
17 #include "LLVMContextImpl.h"
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/ADT/StringExtras.h"
20 #include "llvm/Support/Atomic.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Support/ManagedStatic.h"
23 #include "llvm/Support/Mutex.h"
24 #include "llvm/Support/raw_ostream.h"
25 #include "llvm/Type.h"
28 //===----------------------------------------------------------------------===//
29 // Attribute Implementation
30 //===----------------------------------------------------------------------===//
32 Attribute Attribute::get(LLVMContext &Context, ArrayRef<AttrVal> Vals) {
34 for (ArrayRef<AttrVal>::iterator I = Vals.begin(), E = Vals.end();
37 return Attribute::get(Context, B);
40 Attribute Attribute::get(LLVMContext &Context, AttrBuilder &B) {
41 // If there are no attributes, return an empty Attribute class.
42 if (!B.hasAttributes())
45 // Otherwise, build a key to look up the existing attributes.
46 LLVMContextImpl *pImpl = Context.pImpl;
48 ID.AddInteger(B.Raw());
51 AttributeImpl *PA = pImpl->AttrsSet.FindNodeOrInsertPos(ID, InsertPoint);
54 // If we didn't find any existing attributes of the same shape then create a
55 // new one and insert it.
56 PA = new AttributeImpl(B.Raw());
57 pImpl->AttrsSet.InsertNode(PA, InsertPoint);
60 // Return the AttributesList that we found or created.
64 bool Attribute::hasAttribute(AttrVal Val) const {
65 return Attrs && Attrs->hasAttribute(Val);
68 bool Attribute::hasAttributes() const {
69 return Attrs && Attrs->hasAttributes();
72 bool Attribute::hasAttributes(const Attribute &A) const {
73 return Attrs && Attrs->hasAttributes(A);
76 /// This returns the alignment field of an attribute as a byte alignment value.
77 unsigned Attribute::getAlignment() const {
78 if (!hasAttribute(Attribute::Alignment))
80 return 1U << ((Attrs->getAlignment() >> 16) - 1);
83 /// This returns the stack alignment field of an attribute as a byte alignment
85 unsigned Attribute::getStackAlignment() const {
86 if (!hasAttribute(Attribute::StackAlignment))
88 return 1U << ((Attrs->getStackAlignment() >> 26) - 1);
91 uint64_t Attribute::Raw() const {
92 return Attrs ? Attrs->Raw() : 0;
95 Attribute Attribute::typeIncompatible(Type *Ty) {
96 AttrBuilder Incompatible;
98 if (!Ty->isIntegerTy())
99 // Attribute that only apply to integers.
100 Incompatible.addAttribute(Attribute::SExt)
101 .addAttribute(Attribute::ZExt);
103 if (!Ty->isPointerTy())
104 // Attribute that only apply to pointers.
105 Incompatible.addAttribute(Attribute::ByVal)
106 .addAttribute(Attribute::Nest)
107 .addAttribute(Attribute::NoAlias)
108 .addAttribute(Attribute::NoCapture)
109 .addAttribute(Attribute::StructRet);
111 return Attribute::get(Ty->getContext(), Incompatible);
114 /// encodeLLVMAttributesForBitcode - This returns an integer containing an
115 /// encoding of all the LLVM attributes found in the given attribute bitset.
116 /// Any change to this encoding is a breaking change to bitcode compatibility.
117 uint64_t Attribute::encodeLLVMAttributesForBitcode(Attribute Attrs) {
118 // FIXME: It doesn't make sense to store the alignment information as an
119 // expanded out value, we should store it as a log2 value. However, we can't
120 // just change that here without breaking bitcode compatibility. If this ever
121 // becomes a problem in practice, we should introduce new tag numbers in the
122 // bitcode file and have those tags use a more efficiently encoded alignment
125 // Store the alignment in the bitcode as a 16-bit raw value instead of a 5-bit
126 // log2 encoded value. Shift the bits above the alignment up by 11 bits.
127 uint64_t EncodedAttrs = Attrs.Raw() & 0xffff;
128 if (Attrs.hasAttribute(Attribute::Alignment))
129 EncodedAttrs |= Attrs.getAlignment() << 16;
130 EncodedAttrs |= (Attrs.Raw() & (0xffffULL << 21)) << 11;
134 /// decodeLLVMAttributesForBitcode - This returns an attribute bitset containing
135 /// the LLVM attributes that have been decoded from the given integer. This
136 /// function must stay in sync with 'encodeLLVMAttributesForBitcode'.
137 Attribute Attribute::decodeLLVMAttributesForBitcode(LLVMContext &C,
138 uint64_t EncodedAttrs) {
139 // The alignment is stored as a 16-bit raw value from bits 31--16. We shift
140 // the bits above 31 down by 11 bits.
141 unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16;
142 assert((!Alignment || isPowerOf2_32(Alignment)) &&
143 "Alignment must be a power of two.");
145 AttrBuilder B(EncodedAttrs & 0xffff);
147 B.addAlignmentAttr(Alignment);
148 B.addRawValue((EncodedAttrs & (0xffffULL << 32)) >> 11);
149 return Attribute::get(C, B);
152 std::string Attribute::getAsString() const {
154 if (hasAttribute(Attribute::ZExt))
155 Result += "zeroext ";
156 if (hasAttribute(Attribute::SExt))
157 Result += "signext ";
158 if (hasAttribute(Attribute::NoReturn))
159 Result += "noreturn ";
160 if (hasAttribute(Attribute::NoUnwind))
161 Result += "nounwind ";
162 if (hasAttribute(Attribute::UWTable))
163 Result += "uwtable ";
164 if (hasAttribute(Attribute::ReturnsTwice))
165 Result += "returns_twice ";
166 if (hasAttribute(Attribute::InReg))
168 if (hasAttribute(Attribute::NoAlias))
169 Result += "noalias ";
170 if (hasAttribute(Attribute::NoCapture))
171 Result += "nocapture ";
172 if (hasAttribute(Attribute::StructRet))
174 if (hasAttribute(Attribute::ByVal))
176 if (hasAttribute(Attribute::Nest))
178 if (hasAttribute(Attribute::ReadNone))
179 Result += "readnone ";
180 if (hasAttribute(Attribute::ReadOnly))
181 Result += "readonly ";
182 if (hasAttribute(Attribute::OptimizeForSize))
183 Result += "optsize ";
184 if (hasAttribute(Attribute::NoInline))
185 Result += "noinline ";
186 if (hasAttribute(Attribute::InlineHint))
187 Result += "inlinehint ";
188 if (hasAttribute(Attribute::AlwaysInline))
189 Result += "alwaysinline ";
190 if (hasAttribute(Attribute::StackProtect))
192 if (hasAttribute(Attribute::StackProtectReq))
194 if (hasAttribute(Attribute::NoRedZone))
195 Result += "noredzone ";
196 if (hasAttribute(Attribute::NoImplicitFloat))
197 Result += "noimplicitfloat ";
198 if (hasAttribute(Attribute::Naked))
200 if (hasAttribute(Attribute::NonLazyBind))
201 Result += "nonlazybind ";
202 if (hasAttribute(Attribute::AddressSafety))
203 Result += "address_safety ";
204 if (hasAttribute(Attribute::MinSize))
205 Result += "minsize ";
206 if (hasAttribute(Attribute::StackAlignment)) {
207 Result += "alignstack(";
208 Result += utostr(getStackAlignment());
211 if (hasAttribute(Attribute::Alignment)) {
213 Result += utostr(getAlignment());
216 // Trim the trailing space.
217 assert(!Result.empty() && "Unknown attribute!");
218 Result.erase(Result.end()-1);
222 //===----------------------------------------------------------------------===//
223 // AttrBuilder Implementation
224 //===----------------------------------------------------------------------===//
226 AttrBuilder &AttrBuilder::addAttribute(Attribute::AttrVal Val){
227 Bits |= AttributeImpl::getAttrMask(Val);
231 AttrBuilder &AttrBuilder::addRawValue(uint64_t Val) {
236 AttrBuilder &AttrBuilder::addAlignmentAttr(unsigned Align) {
237 if (Align == 0) return *this;
238 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
239 assert(Align <= 0x40000000 && "Alignment too large.");
240 Bits |= (Log2_32(Align) + 1) << 16;
243 AttrBuilder &AttrBuilder::addStackAlignmentAttr(unsigned Align){
244 // Default alignment, allow the target to define how to align it.
245 if (Align == 0) return *this;
246 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
247 assert(Align <= 0x100 && "Alignment too large.");
248 Bits |= (Log2_32(Align) + 1) << 26;
252 AttrBuilder &AttrBuilder::removeAttribute(Attribute::AttrVal Val) {
253 Bits &= ~AttributeImpl::getAttrMask(Val);
257 AttrBuilder &AttrBuilder::addAttributes(const Attribute &A) {
262 AttrBuilder &AttrBuilder::removeAttributes(const Attribute &A){
267 bool AttrBuilder::hasAttribute(Attribute::AttrVal A) const {
268 return Bits & AttributeImpl::getAttrMask(A);
271 bool AttrBuilder::hasAttributes() const {
274 bool AttrBuilder::hasAttributes(const Attribute &A) const {
275 return Bits & A.Raw();
277 bool AttrBuilder::hasAlignmentAttr() const {
278 return Bits & AttributeImpl::getAttrMask(Attribute::Alignment);
281 uint64_t AttrBuilder::getAlignment() const {
282 if (!hasAlignmentAttr())
285 (((Bits & AttributeImpl::getAttrMask(Attribute::Alignment)) >> 16) - 1);
288 uint64_t AttrBuilder::getStackAlignment() const {
289 if (!hasAlignmentAttr())
292 (((Bits & AttributeImpl::getAttrMask(Attribute::StackAlignment))>>26)-1);
295 //===----------------------------------------------------------------------===//
296 // AttributeImpl Definition
297 //===----------------------------------------------------------------------===//
299 uint64_t AttributeImpl::getAttrMask(uint64_t Val) {
301 case Attribute::None: return 0;
302 case Attribute::ZExt: return 1 << 0;
303 case Attribute::SExt: return 1 << 1;
304 case Attribute::NoReturn: return 1 << 2;
305 case Attribute::InReg: return 1 << 3;
306 case Attribute::StructRet: return 1 << 4;
307 case Attribute::NoUnwind: return 1 << 5;
308 case Attribute::NoAlias: return 1 << 6;
309 case Attribute::ByVal: return 1 << 7;
310 case Attribute::Nest: return 1 << 8;
311 case Attribute::ReadNone: return 1 << 9;
312 case Attribute::ReadOnly: return 1 << 10;
313 case Attribute::NoInline: return 1 << 11;
314 case Attribute::AlwaysInline: return 1 << 12;
315 case Attribute::OptimizeForSize: return 1 << 13;
316 case Attribute::StackProtect: return 1 << 14;
317 case Attribute::StackProtectReq: return 1 << 15;
318 case Attribute::Alignment: return 31 << 16;
319 case Attribute::NoCapture: return 1 << 21;
320 case Attribute::NoRedZone: return 1 << 22;
321 case Attribute::NoImplicitFloat: return 1 << 23;
322 case Attribute::Naked: return 1 << 24;
323 case Attribute::InlineHint: return 1 << 25;
324 case Attribute::StackAlignment: return 7 << 26;
325 case Attribute::ReturnsTwice: return 1 << 29;
326 case Attribute::UWTable: return 1 << 30;
327 case Attribute::NonLazyBind: return 1U << 31;
328 case Attribute::AddressSafety: return 1ULL << 32;
329 case Attribute::MinSize: return 1ULL << 33;
331 llvm_unreachable("Unsupported attribute type");
334 bool AttributeImpl::hasAttribute(uint64_t A) const {
335 return (Bits & getAttrMask(A)) != 0;
338 bool AttributeImpl::hasAttributes() const {
342 bool AttributeImpl::hasAttributes(const Attribute &A) const {
343 return Bits & A.Raw(); // FIXME: Raw() won't work here in the future.
346 uint64_t AttributeImpl::getAlignment() const {
347 return Bits & getAttrMask(Attribute::Alignment);
350 uint64_t AttributeImpl::getStackAlignment() const {
351 return Bits & getAttrMask(Attribute::StackAlignment);
354 //===----------------------------------------------------------------------===//
355 // AttributeSetImpl Definition
356 //===----------------------------------------------------------------------===//
358 AttributeSet AttributeSet::get(LLVMContext &C,
359 ArrayRef<AttributeWithIndex> Attrs) {
360 // If there are no attributes then return a null AttributesList pointer.
362 return AttributeSet();
365 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
366 assert(Attrs[i].Attrs.hasAttributes() &&
367 "Pointless attribute!");
368 assert((!i || Attrs[i-1].Index < Attrs[i].Index) &&
369 "Misordered AttributesList!");
373 // Otherwise, build a key to look up the existing attributes.
374 LLVMContextImpl *pImpl = C.pImpl;
376 AttributeSetImpl::Profile(ID, Attrs);
379 AttributeSetImpl *PA = pImpl->AttrsLists.FindNodeOrInsertPos(ID,
382 // If we didn't find any existing attributes of the same shape then
383 // create a new one and insert it.
385 PA = new AttributeSetImpl(C, Attrs);
386 pImpl->AttrsLists.InsertNode(PA, InsertPoint);
389 // Return the AttributesList that we found or created.
390 return AttributeSet(PA);
393 //===----------------------------------------------------------------------===//
394 // AttributeSet Method Implementations
395 //===----------------------------------------------------------------------===//
397 const AttributeSet &AttributeSet::operator=(const AttributeSet &RHS) {
398 if (AttrList == RHS.AttrList) return *this;
400 AttrList = RHS.AttrList;
404 /// getNumSlots - Return the number of slots used in this attribute list.
405 /// This is the number of arguments that have an attribute set on them
406 /// (including the function itself).
407 unsigned AttributeSet::getNumSlots() const {
408 return AttrList ? AttrList->Attrs.size() : 0;
411 /// getSlot - Return the AttributeWithIndex at the specified slot. This
412 /// holds a number plus a set of attributes.
413 const AttributeWithIndex &AttributeSet::getSlot(unsigned Slot) const {
414 assert(AttrList && Slot < AttrList->Attrs.size() && "Slot # out of range!");
415 return AttrList->Attrs[Slot];
418 /// getAttributes - The attributes for the specified index are returned.
419 /// Attribute for the result are denoted with Idx = 0. Function notes are
420 /// denoted with idx = ~0.
421 Attribute AttributeSet::getAttributes(unsigned Idx) const {
422 if (AttrList == 0) return Attribute();
424 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
425 for (unsigned i = 0, e = Attrs.size(); i != e && Attrs[i].Index <= Idx; ++i)
426 if (Attrs[i].Index == Idx)
427 return Attrs[i].Attrs;
432 /// hasAttrSomewhere - Return true if the specified attribute is set for at
433 /// least one parameter or for the return value.
434 bool AttributeSet::hasAttrSomewhere(Attribute::AttrVal Attr) const {
435 if (AttrList == 0) return false;
437 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
438 for (unsigned i = 0, e = Attrs.size(); i != e; ++i)
439 if (Attrs[i].Attrs.hasAttribute(Attr))
445 unsigned AttributeSet::getNumAttrs() const {
446 return AttrList ? AttrList->Attrs.size() : 0;
449 Attribute &AttributeSet::getAttributesAtIndex(unsigned i) const {
450 assert(AttrList && "Trying to get an attribute from an empty list!");
451 assert(i < AttrList->Attrs.size() && "Index out of range!");
452 return AttrList->Attrs[i].Attrs;
455 AttributeSet AttributeSet::addAttr(LLVMContext &C, unsigned Idx,
456 Attribute Attrs) const {
457 Attribute OldAttrs = getAttributes(Idx);
459 // FIXME it is not obvious how this should work for alignment.
460 // For now, say we can't change a known alignment.
461 unsigned OldAlign = OldAttrs.getAlignment();
462 unsigned NewAlign = Attrs.getAlignment();
463 assert((!OldAlign || !NewAlign || OldAlign == NewAlign) &&
464 "Attempt to change alignment!");
467 AttrBuilder NewAttrs =
468 AttrBuilder(OldAttrs).addAttributes(Attrs);
469 if (NewAttrs == AttrBuilder(OldAttrs))
472 SmallVector<AttributeWithIndex, 8> NewAttrList;
474 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
476 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
477 unsigned i = 0, e = OldAttrList.size();
478 // Copy attributes for arguments before this one.
479 for (; i != e && OldAttrList[i].Index < Idx; ++i)
480 NewAttrList.push_back(OldAttrList[i]);
482 // If there are attributes already at this index, merge them in.
483 if (i != e && OldAttrList[i].Index == Idx) {
485 Attribute::get(C, AttrBuilder(Attrs).
486 addAttributes(OldAttrList[i].Attrs));
490 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
492 // Copy attributes for arguments after this one.
493 NewAttrList.insert(NewAttrList.end(),
494 OldAttrList.begin()+i, OldAttrList.end());
497 return get(C, NewAttrList);
500 AttributeSet AttributeSet::removeAttr(LLVMContext &C, unsigned Idx,
501 Attribute Attrs) const {
503 // FIXME it is not obvious how this should work for alignment.
504 // For now, say we can't pass in alignment, which no current use does.
505 assert(!Attrs.hasAttribute(Attribute::Alignment) &&
506 "Attempt to exclude alignment!");
508 if (AttrList == 0) return AttributeSet();
510 Attribute OldAttrs = getAttributes(Idx);
511 AttrBuilder NewAttrs =
512 AttrBuilder(OldAttrs).removeAttributes(Attrs);
513 if (NewAttrs == AttrBuilder(OldAttrs))
516 SmallVector<AttributeWithIndex, 8> NewAttrList;
517 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
518 unsigned i = 0, e = OldAttrList.size();
520 // Copy attributes for arguments before this one.
521 for (; i != e && OldAttrList[i].Index < Idx; ++i)
522 NewAttrList.push_back(OldAttrList[i]);
524 // If there are attributes already at this index, merge them in.
525 assert(OldAttrList[i].Index == Idx && "Attribute isn't set?");
526 Attrs = Attribute::get(C, AttrBuilder(OldAttrList[i].Attrs).
527 removeAttributes(Attrs));
529 if (Attrs.hasAttributes()) // If any attributes left for this param, add them.
530 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
532 // Copy attributes for arguments after this one.
533 NewAttrList.insert(NewAttrList.end(),
534 OldAttrList.begin()+i, OldAttrList.end());
536 return get(C, NewAttrList);
539 void AttributeSet::dump() const {
541 for (unsigned i = 0; i < getNumSlots(); ++i) {
542 const AttributeWithIndex &PAWI = getSlot(i);
543 dbgs() << "{" << PAWI.Index << "," << PAWI.Attrs.getAsString() << "} ";