1 //=--- AArch64MCExpr.h - AArch64 specific MC expression classes ---*- C++ -*-=// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file describes AArch64-specific MCExprs, used for modifiers like 10 // ":lo12:" or ":gottprel_g1:". 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_LIB_TARGET_AARCH64_MCTARGETDESC_AARCH64MCEXPR_H 15 #define LLVM_LIB_TARGET_AARCH64_MCTARGETDESC_AARCH64MCEXPR_H 16 17 #include "Utils/AArch64BaseInfo.h" 18 #include "llvm/MC/MCExpr.h" 19 #include "llvm/Support/Casting.h" 20 #include "llvm/Support/ErrorHandling.h" 21 22 namespace llvm { 23 24 class AArch64MCExpr : public MCTargetExpr { 25 public: 26 enum VariantKind { 27 // Symbol locations specifying (roughly speaking) what calculation should be 28 // performed to construct the final address for the relocated 29 // symbol. E.g. direct, via the GOT, ... 30 VK_ABS = 0x001, 31 VK_SABS = 0x002, 32 VK_PREL = 0x003, 33 VK_GOT = 0x004, 34 VK_DTPREL = 0x005, 35 VK_GOTTPREL = 0x006, 36 VK_TPREL = 0x007, 37 VK_TLSDESC = 0x008, 38 VK_SECREL = 0x009, 39 VK_AUTH = 0x00a, 40 VK_AUTHADDR = 0x00b, 41 VK_SymLocBits = 0x00f, 42 43 // Variants specifying which part of the final address calculation is 44 // used. E.g. the low 12 bits for an ADD/LDR, the middle 16 bits for a 45 // MOVZ/MOVK. 46 VK_PAGE = 0x010, 47 VK_PAGEOFF = 0x020, 48 VK_HI12 = 0x030, 49 VK_G0 = 0x040, 50 VK_G1 = 0x050, 51 VK_G2 = 0x060, 52 VK_G3 = 0x070, 53 VK_LO15 = 0x080, 54 VK_AddressFragBits = 0x0f0, 55 56 // Whether the final relocation is a checked one (where a linker should 57 // perform a range-check on the final address) or not. Note that this field 58 // is unfortunately sometimes omitted from the assembly syntax. E.g. :lo12: 59 // on its own is a non-checked relocation. We side with ELF on being 60 // explicit about this! 61 VK_NC = 0x100, 62 63 // Convenience definitions for referring to specific textual representations 64 // of relocation specifiers. Note that this means the "_NC" is sometimes 65 // omitted in line with assembly syntax here (VK_LO12 rather than VK_LO12_NC 66 // since a user would write ":lo12:"). 67 VK_CALL = VK_ABS, 68 VK_ABS_PAGE = VK_ABS | VK_PAGE, 69 VK_ABS_PAGE_NC = VK_ABS | VK_PAGE | VK_NC, 70 VK_ABS_G3 = VK_ABS | VK_G3, 71 VK_ABS_G2 = VK_ABS | VK_G2, 72 VK_ABS_G2_S = VK_SABS | VK_G2, 73 VK_ABS_G2_NC = VK_ABS | VK_G2 | VK_NC, 74 VK_ABS_G1 = VK_ABS | VK_G1, 75 VK_ABS_G1_S = VK_SABS | VK_G1, 76 VK_ABS_G1_NC = VK_ABS | VK_G1 | VK_NC, 77 VK_ABS_G0 = VK_ABS | VK_G0, 78 VK_ABS_G0_S = VK_SABS | VK_G0, 79 VK_ABS_G0_NC = VK_ABS | VK_G0 | VK_NC, 80 VK_LO12 = VK_ABS | VK_PAGEOFF | VK_NC, 81 VK_PREL_G3 = VK_PREL | VK_G3, 82 VK_PREL_G2 = VK_PREL | VK_G2, 83 VK_PREL_G2_NC = VK_PREL | VK_G2 | VK_NC, 84 VK_PREL_G1 = VK_PREL | VK_G1, 85 VK_PREL_G1_NC = VK_PREL | VK_G1 | VK_NC, 86 VK_PREL_G0 = VK_PREL | VK_G0, 87 VK_PREL_G0_NC = VK_PREL | VK_G0 | VK_NC, 88 VK_GOT_LO12 = VK_GOT | VK_PAGEOFF | VK_NC, 89 VK_GOT_PAGE = VK_GOT | VK_PAGE, 90 VK_GOT_PAGE_LO15 = VK_GOT | VK_LO15 | VK_NC, 91 VK_DTPREL_G2 = VK_DTPREL | VK_G2, 92 VK_DTPREL_G1 = VK_DTPREL | VK_G1, 93 VK_DTPREL_G1_NC = VK_DTPREL | VK_G1 | VK_NC, 94 VK_DTPREL_G0 = VK_DTPREL | VK_G0, 95 VK_DTPREL_G0_NC = VK_DTPREL | VK_G0 | VK_NC, 96 VK_DTPREL_HI12 = VK_DTPREL | VK_HI12, 97 VK_DTPREL_LO12 = VK_DTPREL | VK_PAGEOFF, 98 VK_DTPREL_LO12_NC = VK_DTPREL | VK_PAGEOFF | VK_NC, 99 VK_GOTTPREL_PAGE = VK_GOTTPREL | VK_PAGE, 100 VK_GOTTPREL_LO12_NC = VK_GOTTPREL | VK_PAGEOFF | VK_NC, 101 VK_GOTTPREL_G1 = VK_GOTTPREL | VK_G1, 102 VK_GOTTPREL_G0_NC = VK_GOTTPREL | VK_G0 | VK_NC, 103 VK_TPREL_G2 = VK_TPREL | VK_G2, 104 VK_TPREL_G1 = VK_TPREL | VK_G1, 105 VK_TPREL_G1_NC = VK_TPREL | VK_G1 | VK_NC, 106 VK_TPREL_G0 = VK_TPREL | VK_G0, 107 VK_TPREL_G0_NC = VK_TPREL | VK_G0 | VK_NC, 108 VK_TPREL_HI12 = VK_TPREL | VK_HI12, 109 VK_TPREL_LO12 = VK_TPREL | VK_PAGEOFF, 110 VK_TPREL_LO12_NC = VK_TPREL | VK_PAGEOFF | VK_NC, 111 VK_TLSDESC_LO12 = VK_TLSDESC | VK_PAGEOFF, 112 VK_TLSDESC_PAGE = VK_TLSDESC | VK_PAGE, 113 VK_SECREL_LO12 = VK_SECREL | VK_PAGEOFF, 114 VK_SECREL_HI12 = VK_SECREL | VK_HI12, 115 116 VK_INVALID = 0xfff 117 }; 118 119 private: 120 const MCExpr *Expr; 121 const VariantKind Kind; 122 123 protected: 124 explicit AArch64MCExpr(const MCExpr *Expr, VariantKind Kind) 125 : Expr(Expr), Kind(Kind) {} 126 127 public: 128 /// @name Construction 129 /// @{ 130 131 static const AArch64MCExpr *create(const MCExpr *Expr, VariantKind Kind, 132 MCContext &Ctx); 133 134 /// @} 135 /// @name Accessors 136 /// @{ 137 138 /// Get the kind of this expression. 139 VariantKind getKind() const { return Kind; } 140 141 /// Get the expression this modifier applies to. 142 const MCExpr *getSubExpr() const { return Expr; } 143 144 /// @} 145 /// @name VariantKind information extractors. 146 /// @{ 147 148 static VariantKind getSymbolLoc(VariantKind Kind) { 149 return static_cast<VariantKind>(Kind & VK_SymLocBits); 150 } 151 152 static VariantKind getAddressFrag(VariantKind Kind) { 153 return static_cast<VariantKind>(Kind & VK_AddressFragBits); 154 } 155 156 static bool isNotChecked(VariantKind Kind) { return Kind & VK_NC; } 157 158 /// @} 159 160 /// Convert the variant kind into an ELF-appropriate modifier 161 /// (e.g. ":got:", ":lo12:"). 162 StringRef getVariantKindName() const; 163 164 void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override; 165 166 void visitUsedExpr(MCStreamer &Streamer) const override; 167 168 MCFragment *findAssociatedFragment() const override; 169 170 bool evaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout, 171 const MCFixup *Fixup) const override; 172 173 void fixELFSymbolsInTLSFixups(MCAssembler &Asm) const override; 174 175 static bool classof(const MCExpr *E) { 176 return E->getKind() == MCExpr::Target; 177 } 178 }; 179 180 class AArch64AuthMCExpr final : public AArch64MCExpr { 181 uint16_t Discriminator; 182 AArch64PACKey::ID Key; 183 184 explicit AArch64AuthMCExpr(const MCExpr *Expr, uint16_t Discriminator, 185 AArch64PACKey::ID Key, bool HasAddressDiversity) 186 : AArch64MCExpr(Expr, HasAddressDiversity ? VK_AUTHADDR : VK_AUTH), 187 Discriminator(Discriminator), Key(Key) {} 188 189 public: 190 static const AArch64AuthMCExpr * 191 create(const MCExpr *Expr, uint16_t Discriminator, AArch64PACKey::ID Key, 192 bool HasAddressDiversity, MCContext &Ctx); 193 194 AArch64PACKey::ID getKey() const { return Key; } 195 uint16_t getDiscriminator() const { return Discriminator; } 196 bool hasAddressDiversity() const { return getKind() == VK_AUTHADDR; } 197 198 void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override; 199 200 void visitUsedExpr(MCStreamer &Streamer) const override; 201 202 MCFragment *findAssociatedFragment() const override; 203 204 bool evaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout, 205 const MCFixup *Fixup) const override; 206 207 static bool classof(const MCExpr *E) { 208 return isa<AArch64MCExpr>(E) && classof(cast<AArch64MCExpr>(E)); 209 } 210 211 static bool classof(const AArch64MCExpr *E) { 212 return E->getKind() == VK_AUTH || E->getKind() == VK_AUTHADDR; 213 } 214 }; 215 } // end namespace llvm 216 217 #endif 218