1 //===- ConstantPools.cpp - ConstantPool class --*- C++ -*---------===// 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 ConstantPool and AssemblerConstantPools classes. 11 // 12 //===----------------------------------------------------------------------===// 13 #include "llvm/ADT/MapVector.h" 14 #include "llvm/MC/ConstantPools.h" 15 #include "llvm/MC/MCContext.h" 16 #include "llvm/MC/MCExpr.h" 17 #include "llvm/MC/MCStreamer.h" 18 19 using namespace llvm; 20 // 21 // ConstantPool implementation 22 // 23 // Emit the contents of the constant pool using the provided streamer. 24 void ConstantPool::emitEntries(MCStreamer &Streamer) { 25 if (Entries.empty()) 26 return; 27 Streamer.EmitDataRegion(MCDR_DataRegion); 28 for (const ConstantPoolEntry &Entry : Entries) { 29 Streamer.EmitCodeAlignment(Entry.Size); // align naturally 30 Streamer.EmitLabel(Entry.Label); 31 Streamer.EmitValue(Entry.Value, Entry.Size, Entry.Loc); 32 } 33 Streamer.EmitDataRegion(MCDR_DataRegionEnd); 34 Entries.clear(); 35 } 36 37 const MCExpr *ConstantPool::addEntry(const MCExpr *Value, MCContext &Context, 38 unsigned Size, SMLoc Loc) { 39 MCSymbol *CPEntryLabel = Context.createTempSymbol(); 40 41 Entries.push_back(ConstantPoolEntry(CPEntryLabel, Value, Size, Loc)); 42 return MCSymbolRefExpr::create(CPEntryLabel, Context); 43 } 44 45 bool ConstantPool::empty() { return Entries.empty(); } 46 47 // 48 // AssemblerConstantPools implementation 49 // 50 ConstantPool *AssemblerConstantPools::getConstantPool(MCSection *Section) { 51 ConstantPoolMapTy::iterator CP = ConstantPools.find(Section); 52 if (CP == ConstantPools.end()) 53 return nullptr; 54 55 return &CP->second; 56 } 57 58 ConstantPool & 59 AssemblerConstantPools::getOrCreateConstantPool(MCSection *Section) { 60 return ConstantPools[Section]; 61 } 62 63 static void emitConstantPool(MCStreamer &Streamer, MCSection *Section, 64 ConstantPool &CP) { 65 if (!CP.empty()) { 66 Streamer.SwitchSection(Section); 67 CP.emitEntries(Streamer); 68 } 69 } 70 71 void AssemblerConstantPools::emitAll(MCStreamer &Streamer) { 72 // Dump contents of assembler constant pools. 73 for (auto &CPI : ConstantPools) { 74 MCSection *Section = CPI.first; 75 ConstantPool &CP = CPI.second; 76 77 emitConstantPool(Streamer, Section, CP); 78 } 79 } 80 81 void AssemblerConstantPools::emitForCurrentSection(MCStreamer &Streamer) { 82 MCSection *Section = Streamer.getCurrentSection().first; 83 if (ConstantPool *CP = getConstantPool(Section)) { 84 emitConstantPool(Streamer, Section, *CP); 85 } 86 } 87 88 const MCExpr *AssemblerConstantPools::addEntry(MCStreamer &Streamer, 89 const MCExpr *Expr, 90 unsigned Size, SMLoc Loc) { 91 MCSection *Section = Streamer.getCurrentSection().first; 92 return getOrCreateConstantPool(Section).addEntry(Expr, Streamer.getContext(), 93 Size, Loc); 94 } 95
