[llvm] r193569 - Move the STT_FILE symbols out of the normal symbol table processing for
Joerg Sonnenberger
joerg at bec.de
Mon Oct 28 18:06:17 PDT 2013
Author: joerg
Date: Mon Oct 28 20:06:17 2013
New Revision: 193569
URL: http://llvm.org/viewvc/llvm-project?rev=193569&view=rev
Log:
Move the STT_FILE symbols out of the normal symbol table processing for
ELF. They can overlap with the other symbols, e.g. if a source file
"foo.c" contains a function "foo" with a static variable "c".
Added:
llvm/trunk/test/MC/ELF/file-double.s
Modified:
llvm/trunk/include/llvm/MC/MCAssembler.h
llvm/trunk/lib/MC/ELFObjectWriter.cpp
llvm/trunk/lib/MC/MCELF.cpp
llvm/trunk/lib/MC/MCELFStreamer.cpp
Modified: llvm/trunk/include/llvm/MC/MCAssembler.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCAssembler.h?rev=193569&r1=193568&r2=193569&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCAssembler.h (original)
+++ llvm/trunk/include/llvm/MC/MCAssembler.h Mon Oct 28 20:06:17 2013
@@ -19,6 +19,7 @@
#include "llvm/MC/MCInst.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/DataTypes.h"
+#include <algorithm>
#include <vector> // FIXME: Shouldn't be needed.
namespace llvm {
@@ -816,6 +817,9 @@ public:
typedef SymbolDataListType::const_iterator const_symbol_iterator;
typedef SymbolDataListType::iterator symbol_iterator;
+ typedef std::vector<std::string> FileNameVectorType;
+ typedef FileNameVectorType::const_iterator const_file_name_iterator;
+
typedef std::vector<IndirectSymbolData>::const_iterator
const_indirect_symbol_iterator;
typedef std::vector<IndirectSymbolData>::iterator indirect_symbol_iterator;
@@ -859,6 +863,9 @@ private:
/// The list of linker options to propagate into the object file.
std::vector<std::vector<std::string> > LinkerOptions;
+ /// List of declared file names
+ FileNameVectorType FileNames;
+
/// The set of function symbols for which a .thumb_func directive has
/// been seen.
//
@@ -1152,6 +1159,20 @@ public:
return *Entry;
}
+ const_file_name_iterator file_names_begin() const {
+ return FileNames.begin();
+ }
+
+ const_file_name_iterator file_names_end() const {
+ return FileNames.end();
+ }
+
+ void addFileName(StringRef FileName) {
+ if (std::find(file_names_begin(), file_names_end(), FileName) ==
+ file_names_end())
+ FileNames.push_back(FileName);
+ }
+
/// @}
void dump();
Modified: llvm/trunk/lib/MC/ELFObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/ELFObjectWriter.cpp?rev=193569&r1=193568&r2=193569&view=diff
==============================================================================
--- llvm/trunk/lib/MC/ELFObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/ELFObjectWriter.cpp Mon Oct 28 20:06:17 2013
@@ -73,10 +73,6 @@ class ELFObjectWriter : public MCObjectW
// Support lexicographic sorting.
bool operator<(const ELFSymbolData &RHS) const {
- if (MCELF::GetType(*SymbolData) == ELF::STT_FILE)
- return true;
- if (MCELF::GetType(*RHS.SymbolData) == ELF::STT_FILE)
- return false;
return SymbolData->getSymbol().getName() <
RHS.SymbolData->getSymbol().getName();
}
@@ -98,6 +94,7 @@ class ELFObjectWriter : public MCObjectW
/// @{
SmallString<256> StringTable;
+ std::vector<uint64_t> FileSymbolData;
std::vector<ELFSymbolData> LocalSymbolData;
std::vector<ELFSymbolData> ExternalSymbolData;
std::vector<ELFSymbolData> UndefinedSymbolData;
@@ -551,7 +548,7 @@ void ELFObjectWriter::WriteSymbol(MCData
uint8_t Type = MCELF::GetType(Data);
uint8_t Info = (Binding << ELF_STB_Shift) | (Type << ELF_STT_Shift);
- // Other and Visibility share the same byte with Visability using the lower
+ // Other and Visibility share the same byte with Visibility using the lower
// 2 bits
uint8_t Visibility = MCELF::GetVisibility(OrigData);
uint8_t Other = MCELF::getOther(OrigData) <<
@@ -590,8 +587,15 @@ void ELFObjectWriter::WriteSymbolTable(M
// The first entry is the undefined symbol entry.
WriteSymbolEntry(SymtabF, ShndxF, 0, 0, 0, 0, 0, 0, false);
+ for (unsigned i = 0, e = FileSymbolData.size(); i != e; ++i) {
+ WriteSymbolEntry(SymtabF, ShndxF, FileSymbolData[i],
+ ELF::STT_FILE | ELF::STB_LOCAL, 0, 0,
+ ELF::STV_DEFAULT, ELF::SHN_ABS, true);
+ }
+
// Write the symbol table entries.
- LastLocalSymbolIndex = LocalSymbolData.size() + 1;
+ LastLocalSymbolIndex = FileSymbolData.size() + LocalSymbolData.size() + 1;
+
for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) {
ELFSymbolData &MSD = LocalSymbolData[i];
WriteSymbol(SymtabF, ShndxF, MSD, Layout);
@@ -880,6 +884,20 @@ void ELFObjectWriter::ComputeSymbolTable
// FIXME: We could optimize suffixes in strtab in the same way we
// optimize them in shstrtab.
+ for (MCAssembler::const_file_name_iterator it = Asm.file_names_begin(),
+ ie = Asm.file_names_end();
+ it != ie;
+ ++it) {
+ StringRef Name = *it;
+ uint64_t &Entry = StringIndexMap[Name];
+ if (!Entry) {
+ Entry = StringTable.size();
+ StringTable += Name;
+ StringTable += '\x00';
+ }
+ FileSymbolData.push_back(Entry);
+ }
+
// Add the data for the symbols.
for (MCAssembler::symbol_iterator it = Asm.symbol_begin(),
ie = Asm.symbol_end(); it != ie; ++it) {
@@ -964,7 +982,7 @@ void ELFObjectWriter::ComputeSymbolTable
// Set the symbol indices. Local symbols must come before all other
// symbols with non-local bindings.
- unsigned Index = 1;
+ unsigned Index = FileSymbolData.size() + 1;
for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i)
LocalSymbolData[i].SymbolData->setIndex(Index++);
@@ -1073,7 +1091,7 @@ void ELFObjectWriter::WriteRelocationsFr
else if (entry.Index < 0)
entry.Index = getSymbolIndexInSymbolTable(Asm, entry.Symbol);
else
- entry.Index += LocalSymbolData.size();
+ entry.Index += FileSymbolData.size() + LocalSymbolData.size();
if (is64Bit()) {
String64(*F, entry.r_offset);
if (TargetObjectWriter->isN64()) {
Modified: llvm/trunk/lib/MC/MCELF.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCELF.cpp?rev=193569&r1=193568&r2=193569&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCELF.cpp (original)
+++ llvm/trunk/lib/MC/MCELF.cpp Mon Oct 28 20:06:17 2013
@@ -36,8 +36,8 @@ unsigned MCELF::GetBinding(const MCSymbo
void MCELF::SetType(MCSymbolData &SD, unsigned Type) {
assert(Type == ELF::STT_NOTYPE || Type == ELF::STT_OBJECT ||
Type == ELF::STT_FUNC || Type == ELF::STT_SECTION ||
- Type == ELF::STT_FILE || Type == ELF::STT_COMMON ||
- Type == ELF::STT_TLS || Type == ELF::STT_GNU_IFUNC);
+ Type == ELF::STT_COMMON || Type == ELF::STT_TLS ||
+ Type == ELF::STT_GNU_IFUNC);
uint32_t OtherFlags = SD.getFlags() & ~(0xf << ELF_STT_Shift);
SD.setFlags(OtherFlags | (Type << ELF_STT_Shift));
@@ -47,8 +47,7 @@ unsigned MCELF::GetType(const MCSymbolDa
uint32_t Type = (SD.getFlags() & (0xf << ELF_STT_Shift)) >> ELF_STT_Shift;
assert(Type == ELF::STT_NOTYPE || Type == ELF::STT_OBJECT ||
Type == ELF::STT_FUNC || Type == ELF::STT_SECTION ||
- Type == ELF::STT_FILE || Type == ELF::STT_COMMON ||
- Type == ELF::STT_TLS || Type == ELF::STT_GNU_IFUNC);
+ Type == ELF::STT_COMMON || Type == ELF::STT_TLS || Type == ELF::STT_GNU_IFUNC);
return Type;
}
Modified: llvm/trunk/lib/MC/MCELFStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCELFStreamer.cpp?rev=193569&r1=193568&r2=193569&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCELFStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCELFStreamer.cpp Mon Oct 28 20:06:17 2013
@@ -316,17 +316,11 @@ void MCELFStreamer::EmitValueToAlignment
ValueSize, MaxBytesToEmit);
}
-
-// Add a symbol for the file name of this module. This is the second
-// entry in the module's symbol table (the first being the null symbol).
+// Add a symbol for the file name of this module. They start after the
+// null symbol and don't count as normal symbol, i.e. a non-STT_FILE symbol
+// with the same name may appear.
void MCELFStreamer::EmitFileDirective(StringRef Filename) {
- MCSymbol *Symbol = getAssembler().getContext().GetOrCreateSymbol(Filename);
- Symbol->setSection(*getCurrentSection().first);
- Symbol->setAbsolute();
-
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
-
- SD.setFlags(ELF_STT_File | ELF_STB_Local | ELF_STV_Default);
+ getAssembler().addFileName(Filename);
}
void MCELFStreamer::EmitIdent(StringRef IdentString) {
Added: llvm/trunk/test/MC/ELF/file-double.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ELF/file-double.s?rev=193569&view=auto
==============================================================================
--- llvm/trunk/test/MC/ELF/file-double.s (added)
+++ llvm/trunk/test/MC/ELF/file-double.s Mon Oct 28 20:06:17 2013
@@ -0,0 +1,47 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -t | FileCheck %s
+
+// Test that a STT_FILE symbol and a symbol of the same name can coexist.
+
+.file "foo.c"
+.file "bar.c"
+ .globl foo.c
+foo.c:
+
+ .globl bar.c
+bar.c:
+
+// CHECK: Symbol {
+// CHECK: Name: foo.c (1)
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Local
+// CHECK-NEXT: Type: File
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: (0xFFF1)
+// CHECK-NEXT: }
+// CHECK: Name: bar.c (7)
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Local
+// CHECK-NEXT: Type: File
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: (0xFFF1)
+// CHECK-NEXT: }
+// CHECK: Symbol {
+// CHECK: Name: bar.c (7)
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Global
+// CHECK-NEXT: Type: None
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: .text (0x1)
+// CHECK-NEXT: }
+// CHECK: Symbol {
+// CHECK: Name: foo.c (1)
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Global
+// CHECK-NEXT: Type: None
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: .text (0x1)
+// CHECK-NEXT: }
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