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
create(const MCExpr * Expr,VariantKind Kind,MCContext & Ctx)28 const AArch64MCExpr *AArch64MCExpr::create(const MCExpr *Expr, VariantKind Kind,
29 MCContext &Ctx) {
30 return new (Ctx) AArch64MCExpr(Expr, Kind);
31 }
32
getVariantKindName() const33 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
printImpl(raw_ostream & OS,const MCAsmInfo * MAI) const78 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
visitUsedExpr(MCStreamer & Streamer) const84 void AArch64MCExpr::visitUsedExpr(MCStreamer &Streamer) const {
85 Streamer.visitUsedExpr(*getSubExpr());
86 }
87
findAssociatedFragment() const88 MCFragment *AArch64MCExpr::findAssociatedFragment() const {
89 llvm_unreachable("FIXME: what goes here?");
90 }
91
evaluateAsRelocatableImpl(MCValue & Res,const MCAsmLayout * Layout,const MCFixup * Fixup) const92 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
fixELFSymbolsInTLSFixupsImpl(const MCExpr * Expr,MCAssembler & Asm)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
fixELFSymbolsInTLSFixups(MCAssembler & Asm) const133 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