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-rw-r--r--contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp289
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diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
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+++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
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+//=-- llvm/CodeGen/DwarfAccelTable.cpp - Dwarf Accelerator Tables -*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf accelerator tables.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DwarfAccelTable.h"
+#include "DwarfCompileUnit.h"
+#include "DwarfDebug.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/DIE.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/Debug.h"
+
+using namespace llvm;
+
+// The length of the header data is always going to be 4 + 4 + 4*NumAtoms.
+DwarfAccelTable::DwarfAccelTable(ArrayRef<DwarfAccelTable::Atom> atomList)
+ : Header(8 + (atomList.size() * 4)), HeaderData(atomList),
+ Entries(Allocator) {}
+
+void DwarfAccelTable::AddName(DwarfStringPoolEntryRef Name, const DIE *die,
+ char Flags) {
+ assert(Data.empty() && "Already finalized!");
+ // If the string is in the list already then add this die to the list
+ // otherwise add a new one.
+ DataArray &DIEs = Entries[Name.getString()];
+ assert(!DIEs.Name || DIEs.Name == Name);
+ DIEs.Name = Name;
+ DIEs.Values.push_back(new (Allocator) HashDataContents(die, Flags));
+}
+
+void DwarfAccelTable::ComputeBucketCount(void) {
+ // First get the number of unique hashes.
+ std::vector<uint32_t> uniques(Data.size());
+ for (size_t i = 0, e = Data.size(); i < e; ++i)
+ uniques[i] = Data[i]->HashValue;
+ array_pod_sort(uniques.begin(), uniques.end());
+ std::vector<uint32_t>::iterator p =
+ std::unique(uniques.begin(), uniques.end());
+ uint32_t num = std::distance(uniques.begin(), p);
+
+ // Then compute the bucket size, minimum of 1 bucket.
+ if (num > 1024)
+ Header.bucket_count = num / 4;
+ else if (num > 16)
+ Header.bucket_count = num / 2;
+ else
+ Header.bucket_count = num > 0 ? num : 1;
+
+ Header.hashes_count = num;
+}
+
+// compareDIEs - comparison predicate that sorts DIEs by their offset.
+static bool compareDIEs(const DwarfAccelTable::HashDataContents *A,
+ const DwarfAccelTable::HashDataContents *B) {
+ return A->Die->getOffset() < B->Die->getOffset();
+}
+
+void DwarfAccelTable::FinalizeTable(AsmPrinter *Asm, StringRef Prefix) {
+ // Create the individual hash data outputs.
+ Data.reserve(Entries.size());
+ for (StringMap<DataArray>::iterator EI = Entries.begin(), EE = Entries.end();
+ EI != EE; ++EI) {
+
+ // Unique the entries.
+ std::stable_sort(EI->second.Values.begin(), EI->second.Values.end(), compareDIEs);
+ EI->second.Values.erase(
+ std::unique(EI->second.Values.begin(), EI->second.Values.end()),
+ EI->second.Values.end());
+
+ HashData *Entry = new (Allocator) HashData(EI->getKey(), EI->second);
+ Data.push_back(Entry);
+ }
+
+ // Figure out how many buckets we need, then compute the bucket
+ // contents and the final ordering. We'll emit the hashes and offsets
+ // by doing a walk during the emission phase. We add temporary
+ // symbols to the data so that we can reference them during the offset
+ // later, we'll emit them when we emit the data.
+ ComputeBucketCount();
+
+ // Compute bucket contents and final ordering.
+ Buckets.resize(Header.bucket_count);
+ for (size_t i = 0, e = Data.size(); i < e; ++i) {
+ uint32_t bucket = Data[i]->HashValue % Header.bucket_count;
+ Buckets[bucket].push_back(Data[i]);
+ Data[i]->Sym = Asm->createTempSymbol(Prefix);
+ }
+
+ // Sort the contents of the buckets by hash value so that hash
+ // collisions end up together. Stable sort makes testing easier and
+ // doesn't cost much more.
+ for (size_t i = 0; i < Buckets.size(); ++i)
+ std::stable_sort(Buckets[i].begin(), Buckets[i].end(),
+ [] (HashData *LHS, HashData *RHS) {
+ return LHS->HashValue < RHS->HashValue;
+ });
+}
+
+// Emits the header for the table via the AsmPrinter.
+void DwarfAccelTable::EmitHeader(AsmPrinter *Asm) {
+ Asm->OutStreamer->AddComment("Header Magic");
+ Asm->EmitInt32(Header.magic);
+ Asm->OutStreamer->AddComment("Header Version");
+ Asm->EmitInt16(Header.version);
+ Asm->OutStreamer->AddComment("Header Hash Function");
+ Asm->EmitInt16(Header.hash_function);
+ Asm->OutStreamer->AddComment("Header Bucket Count");
+ Asm->EmitInt32(Header.bucket_count);
+ Asm->OutStreamer->AddComment("Header Hash Count");
+ Asm->EmitInt32(Header.hashes_count);
+ Asm->OutStreamer->AddComment("Header Data Length");
+ Asm->EmitInt32(Header.header_data_len);
+ Asm->OutStreamer->AddComment("HeaderData Die Offset Base");
+ Asm->EmitInt32(HeaderData.die_offset_base);
+ Asm->OutStreamer->AddComment("HeaderData Atom Count");
+ Asm->EmitInt32(HeaderData.Atoms.size());
+ for (size_t i = 0; i < HeaderData.Atoms.size(); i++) {
+ Atom A = HeaderData.Atoms[i];
+ Asm->OutStreamer->AddComment(dwarf::AtomTypeString(A.type));
+ Asm->EmitInt16(A.type);
+ Asm->OutStreamer->AddComment(dwarf::FormEncodingString(A.form));
+ Asm->EmitInt16(A.form);
+ }
+}
+
+// Walk through and emit the buckets for the table. Each index is
+// an offset into the list of hashes.
+void DwarfAccelTable::EmitBuckets(AsmPrinter *Asm) {
+ unsigned index = 0;
+ for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
+ Asm->OutStreamer->AddComment("Bucket " + Twine(i));
+ if (Buckets[i].size() != 0)
+ Asm->EmitInt32(index);
+ else
+ Asm->EmitInt32(UINT32_MAX);
+ // Buckets point in the list of hashes, not to the data. Do not
+ // increment the index multiple times in case of hash collisions.
+ uint64_t PrevHash = UINT64_MAX;
+ for (auto *HD : Buckets[i]) {
+ uint32_t HashValue = HD->HashValue;
+ if (PrevHash != HashValue)
+ ++index;
+ PrevHash = HashValue;
+ }
+ }
+}
+
+// Walk through the buckets and emit the individual hashes for each
+// bucket.
+void DwarfAccelTable::EmitHashes(AsmPrinter *Asm) {
+ uint64_t PrevHash = UINT64_MAX;
+ for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
+ for (HashList::const_iterator HI = Buckets[i].begin(),
+ HE = Buckets[i].end();
+ HI != HE; ++HI) {
+ uint32_t HashValue = (*HI)->HashValue;
+ if (PrevHash == HashValue)
+ continue;
+ Asm->OutStreamer->AddComment("Hash in Bucket " + Twine(i));
+ Asm->EmitInt32(HashValue);
+ PrevHash = HashValue;
+ }
+ }
+}
+
+// Walk through the buckets and emit the individual offsets for each
+// element in each bucket. This is done via a symbol subtraction from the
+// beginning of the section. The non-section symbol will be output later
+// when we emit the actual data.
+void DwarfAccelTable::emitOffsets(AsmPrinter *Asm, const MCSymbol *SecBegin) {
+ uint64_t PrevHash = UINT64_MAX;
+ for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
+ for (HashList::const_iterator HI = Buckets[i].begin(),
+ HE = Buckets[i].end();
+ HI != HE; ++HI) {
+ uint32_t HashValue = (*HI)->HashValue;
+ if (PrevHash == HashValue)
+ continue;
+ PrevHash = HashValue;
+ Asm->OutStreamer->AddComment("Offset in Bucket " + Twine(i));
+ MCContext &Context = Asm->OutStreamer->getContext();
+ const MCExpr *Sub = MCBinaryExpr::createSub(
+ MCSymbolRefExpr::create((*HI)->Sym, Context),
+ MCSymbolRefExpr::create(SecBegin, Context), Context);
+ Asm->OutStreamer->EmitValue(Sub, sizeof(uint32_t));
+ }
+ }
+}
+
+// Walk through the buckets and emit the full data for each element in
+// the bucket. For the string case emit the dies and the various offsets.
+// Terminate each HashData bucket with 0.
+void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D) {
+ for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
+ uint64_t PrevHash = UINT64_MAX;
+ for (HashList::const_iterator HI = Buckets[i].begin(),
+ HE = Buckets[i].end();
+ HI != HE; ++HI) {
+ // Terminate the previous entry if there is no hash collision
+ // with the current one.
+ if (PrevHash != UINT64_MAX && PrevHash != (*HI)->HashValue)
+ Asm->EmitInt32(0);
+ // Remember to emit the label for our offset.
+ Asm->OutStreamer->EmitLabel((*HI)->Sym);
+ Asm->OutStreamer->AddComment((*HI)->Str);
+ Asm->emitDwarfStringOffset((*HI)->Data.Name);
+ Asm->OutStreamer->AddComment("Num DIEs");
+ Asm->EmitInt32((*HI)->Data.Values.size());
+ for (HashDataContents *HD : (*HI)->Data.Values) {
+ // Emit the DIE offset
+ DwarfCompileUnit *CU = D->lookupUnit(HD->Die->getUnit());
+ assert(CU && "Accelerated DIE should belong to a CU.");
+ Asm->EmitInt32(HD->Die->getOffset() + CU->getDebugInfoOffset());
+ // If we have multiple Atoms emit that info too.
+ // FIXME: A bit of a hack, we either emit only one atom or all info.
+ if (HeaderData.Atoms.size() > 1) {
+ Asm->EmitInt16(HD->Die->getTag());
+ Asm->EmitInt8(HD->Flags);
+ }
+ }
+ PrevHash = (*HI)->HashValue;
+ }
+ // Emit the final end marker for the bucket.
+ if (!Buckets[i].empty())
+ Asm->EmitInt32(0);
+ }
+}
+
+// Emit the entire data structure to the output file.
+void DwarfAccelTable::emit(AsmPrinter *Asm, const MCSymbol *SecBegin,
+ DwarfDebug *D) {
+ // Emit the header.
+ EmitHeader(Asm);
+
+ // Emit the buckets.
+ EmitBuckets(Asm);
+
+ // Emit the hashes.
+ EmitHashes(Asm);
+
+ // Emit the offsets.
+ emitOffsets(Asm, SecBegin);
+
+ // Emit the hash data.
+ EmitData(Asm, D);
+}
+
+#ifndef NDEBUG
+void DwarfAccelTable::print(raw_ostream &O) {
+
+ Header.print(O);
+ HeaderData.print(O);
+
+ O << "Entries: \n";
+ for (StringMap<DataArray>::const_iterator EI = Entries.begin(),
+ EE = Entries.end();
+ EI != EE; ++EI) {
+ O << "Name: " << EI->getKeyData() << "\n";
+ for (HashDataContents *HD : EI->second.Values)
+ HD->print(O);
+ }
+
+ O << "Buckets and Hashes: \n";
+ for (size_t i = 0, e = Buckets.size(); i < e; ++i)
+ for (HashList::const_iterator HI = Buckets[i].begin(),
+ HE = Buckets[i].end();
+ HI != HE; ++HI)
+ (*HI)->print(O);
+
+ O << "Data: \n";
+ for (std::vector<HashData *>::const_iterator DI = Data.begin(),
+ DE = Data.end();
+ DI != DE; ++DI)
+ (*DI)->print(O);
+}
+#endif
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