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 MCAssembler *Asm, |
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 MCAssembler *Asm, |
205 | const MCFixup *Fixup) const override; |
206 | |
207 | static bool classof(const MCExpr *E) { |
208 | return isa<AArch64MCExpr>(Val: E) && classof(E: cast<AArch64MCExpr>(Val: 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 | |