+ if (Attrs.empty()) return AttributeSet();
+ if (Attrs.size() == 1) return Attrs[0];
+
+ SmallVector<std::pair<unsigned, AttributeSetNode*>, 8> AttrNodeVec;
+ AttributeSetImpl *A0 = Attrs[0].pImpl;
+ if (A0)
+ AttrNodeVec.append(A0->getNode(0), A0->getNode(A0->getNumAttributes()));
+ // Copy all attributes from Attrs into AttrNodeVec while keeping AttrNodeVec
+ // ordered by index. Because we know that each list in Attrs is ordered by
+ // index we only need to merge each successive list in rather than doing a
+ // full sort.
+ for (unsigned I = 1, E = Attrs.size(); I != E; ++I) {
+ AttributeSetImpl *AS = Attrs[I].pImpl;
+ if (!AS) continue;
+ SmallVector<std::pair<unsigned, AttributeSetNode *>, 8>::iterator
+ ANVI = AttrNodeVec.begin(), ANVE;
+ for (const AttributeSetImpl::IndexAttrPair
+ *AI = AS->getNode(0),
+ *AE = AS->getNode(AS->getNumAttributes());
+ AI != AE; ++AI) {
+ ANVE = AttrNodeVec.end();
+ while (ANVI != ANVE && ANVI->first <= AI->first)
+ ++ANVI;
+ ANVI = AttrNodeVec.insert(ANVI, *AI) + 1;
+ }
+ }
+
+ return getImpl(C, AttrNodeVec);
+}
+
+AttributeSet AttributeSet::addAttribute(LLVMContext &C, unsigned Index,
+ Attribute::AttrKind Attr) const {
+ if (hasAttribute(Index, Attr)) return *this;
+ return addAttributes(C, Index, AttributeSet::get(C, Index, Attr));
+}
+
+AttributeSet AttributeSet::addAttribute(LLVMContext &C, unsigned Index,
+ StringRef Kind) const {
+ llvm::AttrBuilder B;
+ B.addAttribute(Kind);
+ return addAttributes(C, Index, AttributeSet::get(C, Index, B));
+}
+
+AttributeSet AttributeSet::addAttribute(LLVMContext &C, unsigned Index,
+ StringRef Kind, StringRef Value) const {
+ llvm::AttrBuilder B;
+ B.addAttribute(Kind, Value);
+ return addAttributes(C, Index, AttributeSet::get(C, Index, B));
+}
+
+AttributeSet AttributeSet::addAttributes(LLVMContext &C, unsigned Index,
+ AttributeSet Attrs) const {
+ if (!pImpl) return Attrs;
+ if (!Attrs.pImpl) return *this;
+
+#ifndef NDEBUG
+ // FIXME it is not obvious how this should work for alignment. For now, say
+ // we can't change a known alignment.
+ unsigned OldAlign = getParamAlignment(Index);
+ unsigned NewAlign = Attrs.getParamAlignment(Index);
+ assert((!OldAlign || !NewAlign || OldAlign == NewAlign) &&
+ "Attempt to change alignment!");
+#endif
+
+ // Add the attribute slots before the one we're trying to add.
+ SmallVector<AttributeSet, 4> AttrSet;
+ uint64_t NumAttrs = pImpl->getNumAttributes();
+ AttributeSet AS;
+ uint64_t LastIndex = 0;
+ for (unsigned I = 0, E = NumAttrs; I != E; ++I) {
+ if (getSlotIndex(I) >= Index) {
+ if (getSlotIndex(I) == Index) AS = getSlotAttributes(LastIndex++);
+ break;
+ }
+ LastIndex = I + 1;
+ AttrSet.push_back(getSlotAttributes(I));
+ }
+
+ // Now add the attribute into the correct slot. There may already be an
+ // AttributeSet there.
+ AttrBuilder B(AS, Index);
+
+ for (unsigned I = 0, E = Attrs.pImpl->getNumAttributes(); I != E; ++I)
+ if (Attrs.getSlotIndex(I) == Index) {
+ for (AttributeSetImpl::iterator II = Attrs.pImpl->begin(I),
+ IE = Attrs.pImpl->end(I); II != IE; ++II)
+ B.addAttribute(*II);
+ break;
+ }
+
+ AttrSet.push_back(AttributeSet::get(C, Index, B));
+
+ // Add the remaining attribute slots.
+ for (unsigned I = LastIndex, E = NumAttrs; I < E; ++I)
+ AttrSet.push_back(getSlotAttributes(I));
+
+ return get(C, AttrSet);
+}
+
+AttributeSet AttributeSet::removeAttribute(LLVMContext &C, unsigned Index,
+ Attribute::AttrKind Attr) const {
+ if (!hasAttribute(Index, Attr)) return *this;
+ return removeAttributes(C, Index, AttributeSet::get(C, Index, Attr));
+}
+
+AttributeSet AttributeSet::removeAttributes(LLVMContext &C, unsigned Index,
+ AttributeSet Attrs) const {
+ if (!pImpl) return AttributeSet();
+ if (!Attrs.pImpl) return *this;
+
+#ifndef NDEBUG
+ // FIXME it is not obvious how this should work for alignment.
+ // For now, say we can't pass in alignment, which no current use does.
+ assert(!Attrs.hasAttribute(Index, Attribute::Alignment) &&
+ "Attempt to change alignment!");
+#endif
+
+ // Add the attribute slots before the one we're trying to add.
+ SmallVector<AttributeSet, 4> AttrSet;
+ uint64_t NumAttrs = pImpl->getNumAttributes();
+ AttributeSet AS;
+ uint64_t LastIndex = 0;
+ for (unsigned I = 0, E = NumAttrs; I != E; ++I) {
+ if (getSlotIndex(I) >= Index) {
+ if (getSlotIndex(I) == Index) AS = getSlotAttributes(LastIndex++);
+ break;
+ }
+ LastIndex = I + 1;
+ AttrSet.push_back(getSlotAttributes(I));