Print more information about relocations.

With this patch llvm-readobj now prints if a relocation is pcrel, its length,
if it is extern and if it is scattered.

It also refactors the code a bit to use bit fields instead of shifts and
masks all over the place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179294 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Rafael Espindola
2013-04-11 16:31:37 +00:00
parent c37cb66e6e
commit 4edf092787
5 changed files with 124 additions and 90 deletions
+54 -64
View File
@@ -115,8 +115,23 @@ namespace MachOFormat {
template<endianness TargetEndianness>
struct RelocationEntry {
LLVM_MACHOB_IMPORT_TYPES(TargetEndianness)
MachOInt32 Word0;
MachOInt32 Word1;
MachOInt32 Address;
unsigned SymbolNum : 24;
unsigned PCRel : 1;
unsigned Length : 2;
unsigned External : 1;
unsigned Type : 4;
};
template<endianness TargetEndianness>
struct ScatteredRelocationEntry {
LLVM_MACHOB_IMPORT_TYPES(TargetEndianness)
unsigned Address : 24;
unsigned Type : 4;
unsigned Length : 2;
unsigned PCRel : 1;
unsigned Scattered : 1;
MachOInt32 Value;
};
template<endianness TargetEndianness>
@@ -206,6 +221,8 @@ public:
SymbolTableEntryBase;
typedef MachOFormat::SymtabLoadCommand<support::little> SymtabLoadCommand;
typedef MachOFormat::RelocationEntry<support::little> RelocationEntry;
typedef MachOFormat::ScatteredRelocationEntry<support::little>
ScatteredRelocationEntry;
typedef MachOFormat::SectionBase SectionBase;
typedef MachOFormat::LoadCommand<support::little> LoadCommand;
typedef MachOFormat::Header<support::little> Header;
@@ -243,6 +260,11 @@ public:
const Header *getHeader() const;
unsigned getHeaderSize() const;
StringRef getData(size_t Offset, size_t Size) const;
const RelocationEntry *getRelocation(DataRefImpl Rel) const;
bool isScattered(const RelocationEntry *RE) const;
bool isPCRel(const RelocationEntry *RE) const;
unsigned getLength(const RelocationEntry *RE) const;
unsigned getType(const RelocationEntry *RE) const;
static inline bool classof(const Binary *v) {
return v->isMachO();
@@ -479,15 +501,12 @@ MachOObjectFile<MachOT>::getRelocationAddress(DataRefImpl Rel,
const Section *Sect = getSection(Sections[Rel.d.b]);
uint64_t SectAddress = Sect->Address;
const RelocationEntry *RE = getRelocation(Rel);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
uint64_t RelAddr;
if (isScattered)
RelAddr = RE->Word0 & 0xFFFFFF;
if (isScattered(RE))
RelAddr = RE->Address & 0xFFFFFF;
else
RelAddr = RE->Word0;
RelAddr = RE->Address;
Res = SectAddress + RelAddr;
return object_error::success;
@@ -498,14 +517,10 @@ error_code
MachOObjectFile<MachOT>::getRelocationOffset(DataRefImpl Rel,
uint64_t &Res) const {
const RelocationEntry *RE = getRelocation(Rel);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
if (isScattered)
Res = RE->Word0 & 0xFFFFFF;
if (isScattered(RE))
Res = RE->Address & 0xFFFFFF;
else
Res = RE->Word0;
Res = RE->Address;
return object_error::success;
}
@@ -514,8 +529,8 @@ error_code
MachOObjectFile<MachOT>::getRelocationSymbol(DataRefImpl Rel,
SymbolRef &Res) const {
const RelocationEntry *RE = getRelocation(Rel);
uint32_t SymbolIdx = RE->Word1 & 0xffffff;
bool isExtern = (RE->Word1 >> 27) & 1;
uint32_t SymbolIdx = RE->SymbolNum;
bool isExtern = RE->External;
DataRefImpl Sym;
moveToNextSymbol(Sym);
@@ -535,9 +550,7 @@ template<class MachOT>
error_code MachOObjectFile<MachOT>::getRelocationType(DataRefImpl Rel,
uint64_t &Res) const {
const RelocationEntry *RE = getRelocation(Rel);
Res = RE->Word0;
Res <<= 32;
Res |= RE->Word1;
Res = getType(RE);
return object_error::success;
}
@@ -550,14 +563,8 @@ MachOObjectFile<MachOT>::getRelocationTypeName(DataRefImpl Rel,
const RelocationEntry *RE = getRelocation(Rel);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
unsigned r_type;
if (isScattered)
r_type = (RE->Word0 >> 24) & 0xF;
else
r_type = (RE->Word1 >> 28) & 0xF;
unsigned r_type = getType(RE);
switch (Arch) {
case Triple::x86: {
@@ -650,30 +657,20 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
const RelocationEntry *RE = getRelocation(Rel);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
bool IsScattered = isScattered(RE);
std::string fmtbuf;
raw_string_ostream fmt(fmtbuf);
unsigned Type;
if (isScattered)
Type = (RE->Word0 >> 24) & 0xF;
else
Type = (RE->Word1 >> 28) & 0xF;
bool isPCRel;
if (isScattered)
isPCRel = ((RE->Word0 >> 30) & 1);
else
isPCRel = ((RE->Word1 >> 24) & 1);
unsigned Type = getType(RE);
bool IsPCRel = isPCRel(RE);
// Determine any addends that should be displayed with the relocation.
// These require decoding the relocation type, which is triple-specific.
// X86_64 has entirely custom relocation types.
if (Arch == Triple::x86_64) {
bool isPCRel = ((RE->Word1 >> 24) & 1);
bool isPCRel = RE->PCRel;
switch (Type) {
case macho::RIT_X86_64_GOTLoad: // X86_64_RELOC_GOT_LOAD
@@ -691,7 +688,7 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
// X86_64_SUBTRACTOR must be followed by a relocation of type
// X86_64_RELOC_UNSIGNED.
// NOTE: Scattered relocations don't exist on x86_64.
unsigned RType = (RENext->Word1 >> 28) & 0xF;
unsigned RType = RENext->Type;
if (RType != 0)
report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
"X86_64_RELOC_SUBTRACTOR.");
@@ -738,12 +735,12 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
(RENext->Address & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
RType = (RENext->Address >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
RType = RENext->Type;
if (RType != 1)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_SECTDIFF.");
@@ -767,12 +764,12 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
(RENext->Address & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
RType = (RENext->Address >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
RType = RENext->Type;
if (RType != 1)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_LOCAL_SECTDIFF.");
@@ -785,7 +782,7 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
case macho::RIT_Generic_TLV: {
printRelocationTargetName(RE, fmt);
fmt << "@TLV";
if (isPCRel) fmt << "P";
if (IsPCRel) fmt << "P";
break;
}
default:
@@ -798,10 +795,10 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
// Half relocations steal a bit from the length field to encode
// whether this is an upper16 or a lower16 relocation.
bool isUpper;
if (isScattered)
isUpper = (RE->Word0 >> 28) & 1;
if (IsScattered)
isUpper = (RE->Address >> 28) & 1;
else
isUpper = (RE->Word1 >> 25) & 1;
isUpper = (RE->Length >> 1) & 1;
if (isUpper)
fmt << ":upper16:(";
@@ -816,12 +813,12 @@ MachOObjectFile<MachOT>::getRelocationValueString(DataRefImpl Rel,
// ARM half relocs must be followed by a relocation of type
// ARM_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
(RENext->Address & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
RType = (RENext->Address >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
RType = RENext->Type;
if (RType != 1)
report_fatal_error("Expected ARM_RELOC_PAIR after "
@@ -860,15 +857,8 @@ error_code
MachOObjectFile<MachOT>::getRelocationHidden(DataRefImpl Rel,
bool &Result) const {
const RelocationEntry *RE = getRelocation(Rel);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
unsigned Type;
if (isScattered)
Type = (RE->Word0 >> 24) & 0xF;
else
Type = (RE->Word1 >> 28) & 0xF;
unsigned Type = getType(RE);
Result = false;
@@ -884,7 +874,7 @@ MachOObjectFile<MachOT>::getRelocationHidden(DataRefImpl Rel,
RelPrev.d.a--;
const RelocationEntry *REPrev = getRelocation(RelPrev);
unsigned PrevType = (REPrev->Word1 >> 28) & 0xF;
unsigned PrevType = REPrev->Type;
if (PrevType == macho::RIT_X86_64_Subtractor) Result = true;
}