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/BinaryFormat/ELF.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/Support/ErrorHandling.h"
22
23 using namespace llvm;
24
25 #define DEBUG_TYPE "aarch64symbolrefexpr"
26
create(const MCExpr * Expr,VariantKind Kind,MCContext & Ctx)27 const AArch64MCExpr *AArch64MCExpr::create(const MCExpr *Expr, VariantKind Kind,
28 MCContext &Ctx) {
29 return new (Ctx) AArch64MCExpr(Expr, Kind);
30 }
31
getVariantKindName() const32 StringRef AArch64MCExpr::getVariantKindName() const {
33 switch (static_cast<uint32_t>(getKind())) {
34 case VK_CALL: return "";
35 case VK_LO12: return ":lo12:";
36 case VK_ABS_G3: return ":abs_g3:";
37 case VK_ABS_G2: return ":abs_g2:";
38 case VK_ABS_G2_S: return ":abs_g2_s:";
39 case VK_ABS_G2_NC: return ":abs_g2_nc:";
40 case VK_ABS_G1: return ":abs_g1:";
41 case VK_ABS_G1_S: return ":abs_g1_s:";
42 case VK_ABS_G1_NC: return ":abs_g1_nc:";
43 case VK_ABS_G0: return ":abs_g0:";
44 case VK_ABS_G0_S: return ":abs_g0_s:";
45 case VK_ABS_G0_NC: return ":abs_g0_nc:";
46 case VK_DTPREL_G2: return ":dtprel_g2:";
47 case VK_DTPREL_G1: return ":dtprel_g1:";
48 case VK_DTPREL_G1_NC: return ":dtprel_g1_nc:";
49 case VK_DTPREL_G0: return ":dtprel_g0:";
50 case VK_DTPREL_G0_NC: return ":dtprel_g0_nc:";
51 case VK_DTPREL_HI12: return ":dtprel_hi12:";
52 case VK_DTPREL_LO12: return ":dtprel_lo12:";
53 case VK_DTPREL_LO12_NC: return ":dtprel_lo12_nc:";
54 case VK_TPREL_G2: return ":tprel_g2:";
55 case VK_TPREL_G1: return ":tprel_g1:";
56 case VK_TPREL_G1_NC: return ":tprel_g1_nc:";
57 case VK_TPREL_G0: return ":tprel_g0:";
58 case VK_TPREL_G0_NC: return ":tprel_g0_nc:";
59 case VK_TPREL_HI12: return ":tprel_hi12:";
60 case VK_TPREL_LO12: return ":tprel_lo12:";
61 case VK_TPREL_LO12_NC: return ":tprel_lo12_nc:";
62 case VK_TLSDESC_LO12: return ":tlsdesc_lo12:";
63 case VK_ABS_PAGE: return "";
64 case VK_ABS_PAGE_NC: return ":pg_hi21_nc:";
65 case VK_GOT: return ":got:";
66 case VK_GOT_PAGE: return ":got:";
67 case VK_GOT_LO12: return ":got_lo12:";
68 case VK_GOTTPREL: return ":gottprel:";
69 case VK_GOTTPREL_PAGE: return ":gottprel:";
70 case VK_GOTTPREL_LO12_NC: return ":gottprel_lo12:";
71 case VK_GOTTPREL_G1: return ":gottprel_g1:";
72 case VK_GOTTPREL_G0_NC: return ":gottprel_g0_nc:";
73 case VK_TLSDESC: return "";
74 case VK_TLSDESC_PAGE: return ":tlsdesc:";
75 case VK_SECREL_LO12: return ":secrel_lo12:";
76 case VK_SECREL_HI12: return ":secrel_hi12:";
77 default:
78 llvm_unreachable("Invalid ELF symbol kind");
79 }
80 }
81
printImpl(raw_ostream & OS,const MCAsmInfo * MAI) const82 void AArch64MCExpr::printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const {
83 if (getKind() != VK_NONE)
84 OS << getVariantKindName();
85 Expr->print(OS, MAI);
86 }
87
visitUsedExpr(MCStreamer & Streamer) const88 void AArch64MCExpr::visitUsedExpr(MCStreamer &Streamer) const {
89 Streamer.visitUsedExpr(*getSubExpr());
90 }
91
findAssociatedFragment() const92 MCFragment *AArch64MCExpr::findAssociatedFragment() const {
93 llvm_unreachable("FIXME: what goes here?");
94 }
95
evaluateAsRelocatableImpl(MCValue & Res,const MCAsmLayout * Layout,const MCFixup * Fixup) const96 bool AArch64MCExpr::evaluateAsRelocatableImpl(MCValue &Res,
97 const MCAsmLayout *Layout,
98 const MCFixup *Fixup) const {
99 if (!getSubExpr()->evaluateAsRelocatable(Res, Layout, Fixup))
100 return false;
101
102 Res =
103 MCValue::get(Res.getSymA(), Res.getSymB(), Res.getConstant(), getKind());
104
105 return true;
106 }
107
fixELFSymbolsInTLSFixupsImpl(const MCExpr * Expr,MCAssembler & Asm)108 static void fixELFSymbolsInTLSFixupsImpl(const MCExpr *Expr, MCAssembler &Asm) {
109 switch (Expr->getKind()) {
110 case MCExpr::Target:
111 llvm_unreachable("Can't handle nested target expression");
112 break;
113 case MCExpr::Constant:
114 break;
115
116 case MCExpr::Binary: {
117 const MCBinaryExpr *BE = cast<MCBinaryExpr>(Expr);
118 fixELFSymbolsInTLSFixupsImpl(BE->getLHS(), Asm);
119 fixELFSymbolsInTLSFixupsImpl(BE->getRHS(), Asm);
120 break;
121 }
122
123 case MCExpr::SymbolRef: {
124 // We're known to be under a TLS fixup, so any symbol should be
125 // modified. There should be only one.
126 const MCSymbolRefExpr &SymRef = *cast<MCSymbolRefExpr>(Expr);
127 cast<MCSymbolELF>(SymRef.getSymbol()).setType(ELF::STT_TLS);
128 break;
129 }
130
131 case MCExpr::Unary:
132 fixELFSymbolsInTLSFixupsImpl(cast<MCUnaryExpr>(Expr)->getSubExpr(), Asm);
133 break;
134 }
135 }
136
fixELFSymbolsInTLSFixups(MCAssembler & Asm) const137 void AArch64MCExpr::fixELFSymbolsInTLSFixups(MCAssembler &Asm) const {
138 switch (getSymbolLoc(Kind)) {
139 default:
140 return;
141 case VK_DTPREL:
142 case VK_GOTTPREL:
143 case VK_TPREL:
144 case VK_TLSDESC:
145 break;
146 }
147
148 fixELFSymbolsInTLSFixupsImpl(getSubExpr(), Asm);
149 }
150