1 //===-- AArch64MCExpr.cpp - AArch64 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 // This file contains the implementation of the assembly expression modifiers 11 // accepted by the AArch64 architecture (e.g. ":lo12:", ":gottprel_g1:", ...). 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "AArch64MCExpr.h" 16 #include "llvm/MC/MCAssembler.h" 17 #include "llvm/MC/MCContext.h" 18 #include "llvm/MC/MCStreamer.h" 19 #include "llvm/MC/MCSymbolELF.h" 20 #include "llvm/MC/MCValue.h" 21 #include "llvm/Object/ELF.h" 22 #include "llvm/Support/ErrorHandling.h" 23 24 using namespace llvm; 25 26 #define DEBUG_TYPE "aarch64symbolrefexpr" 27 28 const AArch64MCExpr *AArch64MCExpr::create(const MCExpr *Expr, VariantKind Kind, 29 MCContext &Ctx) { 30 return new (Ctx) AArch64MCExpr(Expr, Kind); 31 } 32 33 StringRef AArch64MCExpr::getVariantKindName() const { 34 switch (static_cast<uint32_t>(getKind())) { 35 case VK_CALL: return ""; 36 case VK_LO12: return ":lo12:"; 37 case VK_ABS_G3: return ":abs_g3:"; 38 case VK_ABS_G2: return ":abs_g2:"; 39 case VK_ABS_G2_S: return ":abs_g2_s:"; 40 case VK_ABS_G2_NC: return ":abs_g2_nc:"; 41 case VK_ABS_G1: return ":abs_g1:"; 42 case VK_ABS_G1_S: return ":abs_g1_s:"; 43 case VK_ABS_G1_NC: return ":abs_g1_nc:"; 44 case VK_ABS_G0: return ":abs_g0:"; 45 case VK_ABS_G0_S: return ":abs_g0_s:"; 46 case VK_ABS_G0_NC: return ":abs_g0_nc:"; 47 case VK_DTPREL_G2: return ":dtprel_g2:"; 48 case VK_DTPREL_G1: return ":dtprel_g1:"; 49 case VK_DTPREL_G1_NC: return ":dtprel_g1_nc:"; 50 case VK_DTPREL_G0: return ":dtprel_g0:"; 51 case VK_DTPREL_G0_NC: return ":dtprel_g0_nc:"; 52 case VK_DTPREL_HI12: return ":dtprel_hi12:"; 53 case VK_DTPREL_LO12: return ":dtprel_lo12:"; 54 case VK_DTPREL_LO12_NC: return ":dtprel_lo12_nc:"; 55 case VK_TPREL_G2: return ":tprel_g2:"; 56 case VK_TPREL_G1: return ":tprel_g1:"; 57 case VK_TPREL_G1_NC: return ":tprel_g1_nc:"; 58 case VK_TPREL_G0: return ":tprel_g0:"; 59 case VK_TPREL_G0_NC: return ":tprel_g0_nc:"; 60 case VK_TPREL_HI12: return ":tprel_hi12:"; 61 case VK_TPREL_LO12: return ":tprel_lo12:"; 62 case VK_TPREL_LO12_NC: return ":tprel_lo12_nc:"; 63 case VK_TLSDESC_LO12: return ":tlsdesc_lo12:"; 64 case VK_ABS_PAGE: return ""; 65 case VK_GOT_PAGE: return ":got:"; 66 case VK_GOT_LO12: return ":got_lo12:"; 67 case VK_GOTTPREL_PAGE: return ":gottprel:"; 68 case VK_GOTTPREL_LO12_NC: return ":gottprel_lo12:"; 69 case VK_GOTTPREL_G1: return ":gottprel_g1:"; 70 case VK_GOTTPREL_G0_NC: return ":gottprel_g0_nc:"; 71 case VK_TLSDESC: return ""; 72 case VK_TLSDESC_PAGE: return ":tlsdesc:"; 73 default: 74 llvm_unreachable("Invalid ELF symbol kind"); 75 } 76 } 77 78 void AArch64MCExpr::printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const { 79 if (getKind() != VK_NONE) 80 OS << getVariantKindName(); 81 Expr->print(OS, MAI); 82 } 83 84 void AArch64MCExpr::visitUsedExpr(MCStreamer &Streamer) const { 85 Streamer.visitUsedExpr(*getSubExpr()); 86 } 87 88 MCFragment *AArch64MCExpr::findAssociatedFragment() const { 89 llvm_unreachable("FIXME: what goes here?"); 90 } 91 92 bool AArch64MCExpr::evaluateAsRelocatableImpl(MCValue &Res, 93 const MCAsmLayout *Layout, 94 const MCFixup *Fixup) const { 95 if (!getSubExpr()->evaluateAsRelocatable(Res, Layout, Fixup)) 96 return false; 97 98 Res = 99 MCValue::get(Res.getSymA(), Res.getSymB(), Res.getConstant(), getKind()); 100 101 return true; 102 } 103 104 static void fixELFSymbolsInTLSFixupsImpl(const MCExpr *Expr, MCAssembler &Asm) { 105 switch (Expr->getKind()) { 106 case MCExpr::Target: 107 llvm_unreachable("Can't handle nested target expression"); 108 break; 109 case MCExpr::Constant: 110 break; 111 112 case MCExpr::Binary: { 113 const MCBinaryExpr *BE = cast<MCBinaryExpr>(Expr); 114 fixELFSymbolsInTLSFixupsImpl(BE->getLHS(), Asm); 115 fixELFSymbolsInTLSFixupsImpl(BE->getRHS(), Asm); 116 break; 117 } 118 119 case MCExpr::SymbolRef: { 120 // We're known to be under a TLS fixup, so any symbol should be 121 // modified. There should be only one. 122 const MCSymbolRefExpr &SymRef = *cast<MCSymbolRefExpr>(Expr); 123 cast<MCSymbolELF>(SymRef.getSymbol()).setType(ELF::STT_TLS); 124 break; 125 } 126 127 case MCExpr::Unary: 128 fixELFSymbolsInTLSFixupsImpl(cast<MCUnaryExpr>(Expr)->getSubExpr(), Asm); 129 break; 130 } 131 } 132 133 void AArch64MCExpr::fixELFSymbolsInTLSFixups(MCAssembler &Asm) const { 134 switch (getSymbolLoc(Kind)) { 135 default: 136 return; 137 case VK_DTPREL: 138 case VK_GOTTPREL: 139 case VK_TPREL: 140 case VK_TLSDESC: 141 break; 142 } 143 144 fixELFSymbolsInTLSFixupsImpl(getSubExpr(), Asm); 145 } 146