1 //===-- PPCMCExpr.cpp - PPC specific MC expression classes ----------------===// 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 #define DEBUG_TYPE "ppcmcexpr" 11 #include "PPCMCExpr.h" 12 #include "llvm/MC/MCAssembler.h" 13 #include "llvm/MC/MCContext.h" 14 #include "llvm/MC/MCAsmInfo.h" 15 16 using namespace llvm; 17 18 const PPCMCExpr* 19 PPCMCExpr::Create(VariantKind Kind, const MCExpr *Expr, 20 MCContext &Ctx) { 21 int AssemblerDialect = Ctx.getAsmInfo()->getAssemblerDialect(); 22 return new (Ctx) PPCMCExpr(Kind, Expr, AssemblerDialect); 23 } 24 25 void PPCMCExpr::PrintImpl(raw_ostream &OS) const { 26 if (isDarwinSyntax()) { 27 switch (Kind) { 28 default: llvm_unreachable("Invalid kind!"); 29 case VK_PPC_LO: OS << "lo16"; break; 30 case VK_PPC_HA: OS << "ha16"; break; 31 } 32 33 OS << '('; 34 getSubExpr()->print(OS); 35 OS << ')'; 36 } else { 37 getSubExpr()->print(OS); 38 39 switch (Kind) { 40 default: llvm_unreachable("Invalid kind!"); 41 case VK_PPC_LO: OS << "@l"; break; 42 case VK_PPC_HA: OS << "@ha"; break; 43 } 44 } 45 } 46 47 bool 48 PPCMCExpr::EvaluateAsRelocatableImpl(MCValue &Res, 49 const MCAsmLayout *Layout) const { 50 MCValue Value; 51 52 if (!getSubExpr()->EvaluateAsRelocatable(Value, *Layout)) 53 return false; 54 55 if (Value.isAbsolute()) { 56 int64_t Result = Value.getConstant(); 57 switch (Kind) { 58 default: 59 llvm_unreachable("Invalid kind!"); 60 case VK_PPC_LO: 61 Result = Result & 0xffff; 62 break; 63 case VK_PPC_HA: 64 Result = ((Result >> 16) + ((Result & 0x8000) ? 1 : 0)) & 0xffff; 65 break; 66 } 67 Res = MCValue::get(Result); 68 } else { 69 MCContext &Context = Layout->getAssembler().getContext(); 70 const MCSymbolRefExpr *Sym = Value.getSymA(); 71 MCSymbolRefExpr::VariantKind Modifier = Sym->getKind(); 72 if (Modifier != MCSymbolRefExpr::VK_None) 73 return false; 74 switch (Kind) { 75 default: 76 llvm_unreachable("Invalid kind!"); 77 case VK_PPC_LO: 78 Modifier = MCSymbolRefExpr::VK_PPC_LO; 79 break; 80 case VK_PPC_HA: 81 Modifier = MCSymbolRefExpr::VK_PPC_HA; 82 break; 83 } 84 Sym = MCSymbolRefExpr::Create(&Sym->getSymbol(), Modifier, Context); 85 Res = MCValue::get(Sym, Value.getSymB(), Value.getConstant()); 86 } 87 88 return true; 89 } 90 91 // FIXME: This basically copies MCObjectStreamer::AddValueSymbols. Perhaps 92 // that method should be made public? 93 static void AddValueSymbols_(const MCExpr *Value, MCAssembler *Asm) { 94 switch (Value->getKind()) { 95 case MCExpr::Target: 96 llvm_unreachable("Can't handle nested target expr!"); 97 98 case MCExpr::Constant: 99 break; 100 101 case MCExpr::Binary: { 102 const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value); 103 AddValueSymbols_(BE->getLHS(), Asm); 104 AddValueSymbols_(BE->getRHS(), Asm); 105 break; 106 } 107 108 case MCExpr::SymbolRef: 109 Asm->getOrCreateSymbolData(cast<MCSymbolRefExpr>(Value)->getSymbol()); 110 break; 111 112 case MCExpr::Unary: 113 AddValueSymbols_(cast<MCUnaryExpr>(Value)->getSubExpr(), Asm); 114 break; 115 } 116 } 117 118 void PPCMCExpr::AddValueSymbols(MCAssembler *Asm) const { 119 AddValueSymbols_(getSubExpr(), Asm); 120 } 121