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Diffstat (limited to 'include/llvm/IR/MDBuilder.h')
| -rw-r--r-- | include/llvm/IR/MDBuilder.h | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/include/llvm/IR/MDBuilder.h b/include/llvm/IR/MDBuilder.h new file mode 100644 index 0000000000..d3ca644a08 --- /dev/null +++ b/include/llvm/IR/MDBuilder.h @@ -0,0 +1,162 @@ +//===---- llvm/MDBuilder.h - Builder for LLVM metadata ----------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the MDBuilder class, which is used as a convenient way to +// create LLVM metadata with a consistent and simplified interface. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_MDBUILDER_H +#define LLVM_MDBUILDER_H + +#include "llvm/ADT/APInt.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Metadata.h" + +namespace llvm { + + class MDBuilder { + LLVMContext &Context; + + public: + MDBuilder(LLVMContext &context) : Context(context) {} + + /// \brief Return the given string as metadata. + MDString *createString(StringRef Str) { + return MDString::get(Context, Str); + } + + //===------------------------------------------------------------------===// + // FPMath metadata. + //===------------------------------------------------------------------===// + + /// \brief Return metadata with the given settings. The special value 0.0 + /// for the Accuracy parameter indicates the default (maximal precision) + /// setting. + MDNode *createFPMath(float Accuracy) { + if (Accuracy == 0.0) + return 0; + assert(Accuracy > 0.0 && "Invalid fpmath accuracy!"); + Value *Op = ConstantFP::get(Type::getFloatTy(Context), Accuracy); + return MDNode::get(Context, Op); + } + + //===------------------------------------------------------------------===// + // Prof metadata. + //===------------------------------------------------------------------===// + + /// \brief Return metadata containing two branch weights. + MDNode *createBranchWeights(uint32_t TrueWeight, uint32_t FalseWeight) { + uint32_t Weights[] = { TrueWeight, FalseWeight }; + return createBranchWeights(Weights); + } + + /// \brief Return metadata containing a number of branch weights. + MDNode *createBranchWeights(ArrayRef<uint32_t> Weights) { + assert(Weights.size() >= 2 && "Need at least two branch weights!"); + + SmallVector<Value *, 4> Vals(Weights.size()+1); + Vals[0] = createString("branch_weights"); + + Type *Int32Ty = Type::getInt32Ty(Context); + for (unsigned i = 0, e = Weights.size(); i != e; ++i) + Vals[i+1] = ConstantInt::get(Int32Ty, Weights[i]); + + return MDNode::get(Context, Vals); + } + + //===------------------------------------------------------------------===// + // Range metadata. + //===------------------------------------------------------------------===// + + /// \brief Return metadata describing the range [Lo, Hi). + MDNode *createRange(const APInt &Lo, const APInt &Hi) { + assert(Lo.getBitWidth() == Hi.getBitWidth() && "Mismatched bitwidths!"); + // If the range is everything then it is useless. + if (Hi == Lo) + return 0; + + // Return the range [Lo, Hi). + Type *Ty = IntegerType::get(Context, Lo.getBitWidth()); + Value *Range[2] = { ConstantInt::get(Ty, Lo), ConstantInt::get(Ty, Hi) }; + return MDNode::get(Context, Range); + } + + + //===------------------------------------------------------------------===// + // TBAA metadata. + //===------------------------------------------------------------------===// + + /// \brief Return metadata appropriate for a TBAA root node. Each returned + /// node is distinct from all other metadata and will never be identified + /// (uniqued) with anything else. + MDNode *createAnonymousTBAARoot() { + // To ensure uniqueness the root node is self-referential. + MDNode *Dummy = MDNode::getTemporary(Context, ArrayRef<Value*>()); + MDNode *Root = MDNode::get(Context, Dummy); + // At this point we have + // !0 = metadata !{} <- dummy + // !1 = metadata !{metadata !0} <- root + // Replace the dummy operand with the root node itself and delete the dummy. + Root->replaceOperandWith(0, Root); + MDNode::deleteTemporary(Dummy); + // We now have + // !1 = metadata !{metadata !1} <- self-referential root + return Root; + } + + /// \brief Return metadata appropriate for a TBAA root node with the given + /// name. This may be identified (uniqued) with other roots with the same + /// name. + MDNode *createTBAARoot(StringRef Name) { + return MDNode::get(Context, createString(Name)); + } + + /// \brief Return metadata for a non-root TBAA node with the given name, + /// parent in the TBAA tree, and value for 'pointsToConstantMemory'. + MDNode *createTBAANode(StringRef Name, MDNode *Parent, + bool isConstant = false) { + if (isConstant) { + Constant *Flags = ConstantInt::get(Type::getInt64Ty(Context), 1); + Value *Ops[3] = { createString(Name), Parent, Flags }; + return MDNode::get(Context, Ops); + } else { + Value *Ops[2] = { createString(Name), Parent }; + return MDNode::get(Context, Ops); + } + } + + struct TBAAStructField { + uint64_t Offset; + uint64_t Size; + MDNode *TBAA; + TBAAStructField(uint64_t Offset, uint64_t Size, MDNode *TBAA) : + Offset(Offset), Size(Size), TBAA(TBAA) {} + }; + + /// \brief Return metadata for a tbaa.struct node with the given + /// struct field descriptions. + MDNode *createTBAAStructNode(ArrayRef<TBAAStructField> Fields) { + SmallVector<Value *, 4> Vals(Fields.size() * 3); + Type *Int64 = IntegerType::get(Context, 64); + for (unsigned i = 0, e = Fields.size(); i != e; ++i) { + Vals[i * 3 + 0] = ConstantInt::get(Int64, Fields[i].Offset); + Vals[i * 3 + 1] = ConstantInt::get(Int64, Fields[i].Size); + Vals[i * 3 + 2] = Fields[i].TBAA; + } + return MDNode::get(Context, Vals); + } + + }; + +} // end namespace llvm + +#endif |