LLVM  7.0.0svn
AArch64MCExpr.cpp
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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/MCContext.h"
17 #include "llvm/MC/MCStreamer.h"
18 #include "llvm/MC/MCSymbolELF.h"
19 #include "llvm/MC/MCValue.h"
20 #include "llvm/Object/ELF.h"
22 
23 using namespace llvm;
24 
25 #define DEBUG_TYPE "aarch64symbolrefexpr"
26 
28  MCContext &Ctx) {
29  return new (Ctx) AArch64MCExpr(Expr, Kind);
30 }
31 
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_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 
85  Streamer.visitUsedExpr(*getSubExpr());
86 }
87 
89  llvm_unreachable("FIXME: what goes here?");
90 }
91 
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 
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);
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 
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 
145 }
VariantKind getKind() const
Get the kind of this expression.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
This represents an "assembler immediate".
Definition: MCValue.h:40
static const AArch64MCExpr * create(const MCExpr *Expr, VariantKind Kind, MCContext &Ctx)
const MCExpr * getLHS() const
Get the left-hand side expression of the binary operator.
Definition: MCExpr.h:554
StringRef getVariantKindName() const
Convert the variant kind into an ELF-appropriate modifier (e.g.
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:66
int64_t getConstant() const
Definition: MCValue.h:47
const MCSymbolRefExpr * getSymB() const
Definition: MCValue.h:49
Encapsulates the layout of an assembly file at a particular point in time.
Definition: MCAsmLayout.h:29
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:36
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:165
bool evaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout, const MCFixup *Fixup) const override
Context object for machine code objects.
Definition: MCContext.h:60
bool evaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout, const MCFixup *Fixup) const
Try to evaluate the expression to a relocatable value, i.e.
Definition: MCExpr.cpp:604
const MCExpr * getRHS() const
Get the right-hand side expression of the binary operator.
Definition: MCExpr.h:557
Unary expressions.
Definition: MCExpr.h:42
This class is intended to be used as a base class for asm properties and features specific to the tar...
Definition: MCAsmInfo.h:56
Streaming machine code generation interface.
Definition: MCStreamer.h:181
void print(raw_ostream &OS, const MCAsmInfo *MAI, bool InParens=false) const
Definition: MCExpr.cpp:40
const MCExpr * getSubExpr() const
Get the expression this modifier applies to.
const MCSymbolRefExpr * getSymA() const
Definition: MCValue.h:48
void visitUsedExpr(MCStreamer &Streamer) const override
Binary assembler expressions.
Definition: MCExpr.h:407
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
const MCSymbol & getSymbol() const
Definition: MCExpr.h:326
ExprKind getKind() const
Definition: MCExpr.h:73
void visitUsedExpr(const MCExpr &Expr)
Definition: MCStreamer.cpp:852
static void fixELFSymbolsInTLSFixupsImpl(const MCExpr *Expr, MCAssembler &Asm)
static MCValue get(const MCSymbolRefExpr *SymA, const MCSymbolRefExpr *SymB=nullptr, int64_t Val=0, uint32_t RefKind=0)
Definition: MCValue.h:63
References to labels and assigned expressions.
Definition: MCExpr.h:41
static VariantKind getSymbolLoc(VariantKind Kind)
void printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const override
const unsigned Kind
Constant expressions.
Definition: MCExpr.h:40
Binary expressions.
Definition: MCExpr.h:39
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
void fixELFSymbolsInTLSFixups(MCAssembler &Asm) const override
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Target specific expression.
Definition: MCExpr.h:43
MCFragment * findAssociatedFragment() const override