1 //===- lib/MC/MCELF.cpp - MC ELF ------------------------------------------===//
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 implements ELF object file writer information.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/MC/MCELF.h"
15 #include "llvm/MC/MCAssembler.h"
16 #include "llvm/MC/MCELFSymbolFlags.h"
17 #include "llvm/MC/MCFixupKindInfo.h"
18 #include "llvm/Support/ELF.h"
19 
20 namespace llvm {
21 
SetBinding(MCSymbolData & SD,unsigned Binding)22 void MCELF::SetBinding(MCSymbolData &SD, unsigned Binding) {
23   assert(Binding == ELF::STB_LOCAL || Binding == ELF::STB_GLOBAL ||
24          Binding == ELF::STB_WEAK || Binding == ELF::STB_GNU_UNIQUE);
25   uint32_t OtherFlags = SD.getFlags() & ~(0xf << ELF_STB_Shift);
26   SD.setFlags(OtherFlags | (Binding << ELF_STB_Shift));
27 }
28 
GetBinding(const MCSymbolData & SD)29 unsigned MCELF::GetBinding(const MCSymbolData &SD) {
30   uint32_t Binding = (SD.getFlags() & (0xf << ELF_STB_Shift)) >> ELF_STB_Shift;
31   assert(Binding == ELF::STB_LOCAL || Binding == ELF::STB_GLOBAL ||
32          Binding == ELF::STB_WEAK || Binding == ELF::STB_GNU_UNIQUE);
33   return Binding;
34 }
35 
SetType(MCSymbolData & SD,unsigned Type)36 void MCELF::SetType(MCSymbolData &SD, unsigned Type) {
37   assert(Type == ELF::STT_NOTYPE || Type == ELF::STT_OBJECT ||
38          Type == ELF::STT_FUNC || Type == ELF::STT_SECTION ||
39          Type == ELF::STT_COMMON || Type == ELF::STT_TLS ||
40          Type == ELF::STT_GNU_IFUNC);
41 
42   uint32_t OtherFlags = SD.getFlags() & ~(0xf << ELF_STT_Shift);
43   SD.setFlags(OtherFlags | (Type << ELF_STT_Shift));
44 }
45 
GetType(const MCSymbolData & SD)46 unsigned MCELF::GetType(const MCSymbolData &SD) {
47   uint32_t Type = (SD.getFlags() & (0xf << ELF_STT_Shift)) >> ELF_STT_Shift;
48   assert(Type == ELF::STT_NOTYPE || Type == ELF::STT_OBJECT ||
49          Type == ELF::STT_FUNC || Type == ELF::STT_SECTION ||
50          Type == ELF::STT_COMMON || Type == ELF::STT_TLS || Type == ELF::STT_GNU_IFUNC);
51   return Type;
52 }
53 
54 // Visibility is stored in the first two bits of st_other
55 // st_other values are stored in the second byte of get/setFlags
SetVisibility(MCSymbolData & SD,unsigned Visibility)56 void MCELF::SetVisibility(MCSymbolData &SD, unsigned Visibility) {
57   assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
58          Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
59 
60   uint32_t OtherFlags = SD.getFlags() & ~(0x3 << ELF_STV_Shift);
61   SD.setFlags(OtherFlags | (Visibility << ELF_STV_Shift));
62 }
63 
GetVisibility(const MCSymbolData & SD)64 unsigned MCELF::GetVisibility(const MCSymbolData &SD) {
65   unsigned Visibility =
66     (SD.getFlags() & (0x3 << ELF_STV_Shift)) >> ELF_STV_Shift;
67   assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
68          Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
69   return Visibility;
70 }
71 
72 // Other is stored in the last six bits of st_other
73 // st_other values are stored in the second byte of get/setFlags
setOther(MCSymbolData & SD,unsigned Other)74 void MCELF::setOther(MCSymbolData &SD, unsigned Other) {
75   uint32_t OtherFlags = SD.getFlags() & ~(0x3f << ELF_STO_Shift);
76   SD.setFlags(OtherFlags | (Other << ELF_STO_Shift));
77 }
78 
getOther(const MCSymbolData & SD)79 unsigned MCELF::getOther(const MCSymbolData &SD) {
80   unsigned Other =
81     (SD.getFlags() & (0x3f << ELF_STO_Shift)) >> ELF_STO_Shift;
82   return Other;
83 }
84 
85 }
86