LLVM  6.0.0svn
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/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"
23 
24 using namespace llvm;
25 
26 #define DEBUG_TYPE "aarch64symbolrefexpr"
27 
29  MCContext &Ctx) {
30  return new (Ctx) AArch64MCExpr(Expr, Kind);
31 }
32 
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_ABS_PAGE_NC: return ":pg_hi21_nc:";
66  case VK_GOT_PAGE: return ":got:";
67  case VK_GOT_LO12: return ":got_lo12:";
68  case VK_GOTTPREL_PAGE: return ":gottprel:";
69  case VK_GOTTPREL_LO12_NC: return ":gottprel_lo12:";
70  case VK_GOTTPREL_G1: return ":gottprel_g1:";
71  case VK_GOTTPREL_G0_NC: return ":gottprel_g0_nc:";
72  case VK_TLSDESC: return "";
73  case VK_TLSDESC_PAGE: return ":tlsdesc:";
74  default:
75  llvm_unreachable("Invalid ELF symbol kind");
76  }
77 }
78 
79 void AArch64MCExpr::printImpl(raw_ostream &OS, const MCAsmInfo *MAI) const {
80  if (getKind() != VK_NONE)
81  OS << getVariantKindName();
82  Expr->print(OS, MAI);
83 }
84 
86  Streamer.visitUsedExpr(*getSubExpr());
87 }
88 
90  llvm_unreachable("FIXME: what goes here?");
91 }
92 
94  const MCAsmLayout *Layout,
95  const MCFixup *Fixup) const {
96  if (!getSubExpr()->evaluateAsRelocatable(Res, Layout, Fixup))
97  return false;
98 
99  Res =
100  MCValue::get(Res.getSymA(), Res.getSymB(), Res.getConstant(), getKind());
101 
102  return true;
103 }
104 
106  switch (Expr->getKind()) {
107  case MCExpr::Target:
108  llvm_unreachable("Can't handle nested target expression");
109  break;
110  case MCExpr::Constant:
111  break;
112 
113  case MCExpr::Binary: {
114  const MCBinaryExpr *BE = cast<MCBinaryExpr>(Expr);
117  break;
118  }
119 
120  case MCExpr::SymbolRef: {
121  // We're known to be under a TLS fixup, so any symbol should be
122  // modified. There should be only one.
123  const MCSymbolRefExpr &SymRef = *cast<MCSymbolRefExpr>(Expr);
124  cast<MCSymbolELF>(SymRef.getSymbol()).setType(ELF::STT_TLS);
125  break;
126  }
127 
128  case MCExpr::Unary:
129  fixELFSymbolsInTLSFixupsImpl(cast<MCUnaryExpr>(Expr)->getSubExpr(), Asm);
130  break;
131  }
132 }
133 
135  switch (getSymbolLoc(Kind)) {
136  default:
137  return;
138  case VK_DTPREL:
139  case VK_GOTTPREL:
140  case VK_TPREL:
141  case VK_TLSDESC:
142  break;
143  }
144 
146 }
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:546
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:59
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:594
const MCExpr * getRHS() const
Get the right-hand side expression of the binary operator.
Definition: MCExpr.h:549
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:169
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:399
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
const MCSymbol & getSymbol() const
Definition: MCExpr.h:318
ExprKind getKind() const
Definition: MCExpr.h:73
void visitUsedExpr(const MCExpr &Expr)
Definition: MCStreamer.cpp:837
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