llvm-6502/lib/MC/MCSymbolELF.cpp
Rafael Espindola cddcabadf2 Bring back r239006 with a fix.
The fix is just that getOther had not been updated for packing the st_other
values in fewer bits and could return spurious values:

-  unsigned Other = (getFlags() & (0x3f << ELF_STO_Shift)) >> ELF_STO_Shift;
+  unsigned Other = (getFlags() & (0x7 << ELF_STO_Shift)) >> ELF_STO_Shift;

Original message:

Pack the MCSymbolELF bit fields into MCSymbol's Flags.

This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.

While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239012 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-04 05:59:23 +00:00

214 lines
5.2 KiB
C++

//===- lib/MC/MCSymbolELF.cpp ---------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCSymbolELF.h"
#include "llvm/MC/MCFixupKindInfo.h"
#include "llvm/Support/ELF.h"
namespace llvm {
namespace {
enum {
// Shift value for STT_* flags. 7 possible values. 3 bits.
ELF_STT_Shift = 0,
// Shift value for STB_* flags. 4 possible values, 2 bits.
ELF_STB_Shift = 3,
// Shift value for STV_* flags. 4 possible values, 2 bits.
ELF_STV_Shift = 5,
// Shift value for STO_* flags. 3 bits. All the values are between 0x20 and
// 0xe0, so we shift right by 5 before storing.
ELF_STO_Shift = 7,
// One bit.
ELF_IsSignature_Shift = 10,
// One bit.
ELF_WeakrefUsedInReloc_Shift = 11,
// One bit.
ELF_UsedInReloc_Shift = 12,
// One bit.
ELF_BindingSet_Shift = 13
};
}
void MCSymbolELF::setBinding(unsigned Binding) const {
setIsBindingSet();
unsigned Val;
switch (Binding) {
default:
llvm_unreachable("Unsupported Binding");
case ELF::STB_LOCAL:
Val = 0;
break;
case ELF::STB_GLOBAL:
Val = 1;
break;
case ELF::STB_WEAK:
Val = 2;
break;
case ELF::STB_GNU_UNIQUE:
Val = 3;
break;
}
uint32_t OtherFlags = getFlags() & ~(0x3 << ELF_STB_Shift);
setFlags(OtherFlags | (Val << ELF_STB_Shift));
}
unsigned MCSymbolELF::getBinding() const {
if (isBindingSet()) {
uint32_t Val = (getFlags() & (0x3 << ELF_STB_Shift)) >> ELF_STB_Shift;
switch (Val) {
default:
llvm_unreachable("Invalid value");
case 0:
return ELF::STB_LOCAL;
case 1:
return ELF::STB_GLOBAL;
case 2:
return ELF::STB_WEAK;
case 3:
return ELF::STB_GNU_UNIQUE;
}
}
if (isDefined())
return ELF::STB_LOCAL;
if (isUsedInReloc())
return ELF::STB_GLOBAL;
if (isWeakrefUsedInReloc())
return ELF::STB_WEAK;
if (isSignature())
return ELF::STB_LOCAL;
return ELF::STB_GLOBAL;
}
void MCSymbolELF::setType(unsigned Type) const {
unsigned Val;
switch (Type) {
default:
llvm_unreachable("Unsupported Binding");
case ELF::STT_NOTYPE:
Val = 0;
break;
case ELF::STT_OBJECT:
Val = 1;
break;
case ELF::STT_FUNC:
Val = 2;
break;
case ELF::STT_SECTION:
Val = 3;
break;
case ELF::STT_COMMON:
Val = 4;
break;
case ELF::STT_TLS:
Val = 5;
break;
case ELF::STT_GNU_IFUNC:
Val = 6;
break;
}
uint32_t OtherFlags = getFlags() & ~(0x7 << ELF_STT_Shift);
setFlags(OtherFlags | (Val << ELF_STT_Shift));
}
unsigned MCSymbolELF::getType() const {
uint32_t Val = (getFlags() & (0x7 << ELF_STT_Shift)) >> ELF_STT_Shift;
switch (Val) {
default:
llvm_unreachable("Invalid value");
case 0:
return ELF::STT_NOTYPE;
case 1:
return ELF::STT_OBJECT;
case 2:
return ELF::STT_FUNC;
case 3:
return ELF::STT_SECTION;
case 4:
return ELF::STT_COMMON;
case 5:
return ELF::STT_TLS;
case 6:
return ELF::STT_GNU_IFUNC;
}
}
void MCSymbolELF::setVisibility(unsigned Visibility) {
assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
uint32_t OtherFlags = getFlags() & ~(0x3 << ELF_STV_Shift);
setFlags(OtherFlags | (Visibility << ELF_STV_Shift));
}
unsigned MCSymbolELF::getVisibility() const {
unsigned Visibility = (getFlags() & (0x3 << ELF_STV_Shift)) >> ELF_STV_Shift;
assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
return Visibility;
}
void MCSymbolELF::setOther(unsigned Other) {
assert((Other & 0x1f) == 0);
Other >>= 5;
assert(Other <= 0x7);
uint32_t OtherFlags = getFlags() & ~(0x7 << ELF_STO_Shift);
setFlags(OtherFlags | (Other << ELF_STO_Shift));
}
unsigned MCSymbolELF::getOther() const {
unsigned Other = (getFlags() & (0x7 << ELF_STO_Shift)) >> ELF_STO_Shift;
return Other << 5;
}
void MCSymbolELF::setUsedInReloc() const {
uint32_t OtherFlags = getFlags() & ~(0x1 << ELF_UsedInReloc_Shift);
setFlags(OtherFlags | (1 << ELF_UsedInReloc_Shift));
}
bool MCSymbolELF::isUsedInReloc() const {
return getFlags() & (0x1 << ELF_UsedInReloc_Shift);
}
void MCSymbolELF::setIsWeakrefUsedInReloc() const {
uint32_t OtherFlags = getFlags() & ~(0x1 << ELF_WeakrefUsedInReloc_Shift);
setFlags(OtherFlags | (1 << ELF_WeakrefUsedInReloc_Shift));
}
bool MCSymbolELF::isWeakrefUsedInReloc() const {
return getFlags() & (0x1 << ELF_WeakrefUsedInReloc_Shift);
}
void MCSymbolELF::setIsSignature() const {
uint32_t OtherFlags = getFlags() & ~(0x1 << ELF_IsSignature_Shift);
setFlags(OtherFlags | (1 << ELF_IsSignature_Shift));
}
bool MCSymbolELF::isSignature() const {
return getFlags() & (0x1 << ELF_IsSignature_Shift);
}
void MCSymbolELF::setIsBindingSet() const {
uint32_t OtherFlags = getFlags() & ~(0x1 << ELF_BindingSet_Shift);
setFlags(OtherFlags | (1 << ELF_BindingSet_Shift));
}
bool MCSymbolELF::isBindingSet() const {
return getFlags() & (0x1 << ELF_BindingSet_Shift);
}
}