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 (EntryVecTy::const_iterator I = Entries.begin(), E = Entries.end(); 29 I != E; ++I) { 30 Streamer.EmitCodeAlignment(I->Size); // align naturally 31 Streamer.EmitLabel(I->Label); 32 Streamer.EmitValue(I->Value, I->Size); 33 } 34 Streamer.EmitDataRegion(MCDR_DataRegionEnd); 35 Entries.clear(); 36 } 37 38 const MCExpr *ConstantPool::addEntry(const MCExpr *Value, MCContext &Context, 39 unsigned Size) { 40 MCSymbol *CPEntryLabel = Context.CreateTempSymbol(); 41 42 Entries.push_back(ConstantPoolEntry(CPEntryLabel, Value, Size)); 43 return MCSymbolRefExpr::Create(CPEntryLabel, Context); 44 } 45 46 bool ConstantPool::empty() { return Entries.empty(); } 47 48 // 49 // AssemblerConstantPools implementation 50 // 51 ConstantPool * 52 AssemblerConstantPools::getConstantPool(const MCSection *Section) { 53 ConstantPoolMapTy::iterator CP = ConstantPools.find(Section); 54 if (CP == ConstantPools.end()) 55 return nullptr; 56 57 return &CP->second; 58 } 59 60 ConstantPool & 61 AssemblerConstantPools::getOrCreateConstantPool(const MCSection *Section) { 62 return ConstantPools[Section]; 63 } 64 65 static void emitConstantPool(MCStreamer &Streamer, const MCSection *Section, 66 ConstantPool &CP) { 67 if (!CP.empty()) { 68 Streamer.SwitchSection(Section); 69 CP.emitEntries(Streamer); 70 } 71 } 72 73 void AssemblerConstantPools::emitAll(MCStreamer &Streamer) { 74 // Dump contents of assembler constant pools. 75 for (ConstantPoolMapTy::iterator CPI = ConstantPools.begin(), 76 CPE = ConstantPools.end(); 77 CPI != CPE; ++CPI) { 78 const MCSection *Section = CPI->first; 79 ConstantPool &CP = CPI->second; 80 81 emitConstantPool(Streamer, Section, CP); 82 } 83 } 84 85 void AssemblerConstantPools::emitForCurrentSection(MCStreamer &Streamer) { 86 const MCSection *Section = Streamer.getCurrentSection().first; 87 if (ConstantPool *CP = getConstantPool(Section)) { 88 emitConstantPool(Streamer, Section, *CP); 89 } 90 } 91 92 const MCExpr *AssemblerConstantPools::addEntry(MCStreamer &Streamer, 93 const MCExpr *Expr, 94 unsigned Size) { 95 const MCSection *Section = Streamer.getCurrentSection().first; 96 return getOrCreateConstantPool(Section).addEntry(Expr, Streamer.getContext(), 97 Size); 98 } 99