Index: courgette/disassembler_elf_32.cc |
diff --git a/courgette/disassembler_elf_32.cc b/courgette/disassembler_elf_32.cc |
index 6285c3878170f4c2f7371b43282432b8fde688da..4809391fb3bfc59def1ef654d4f04a4169df6f72 100644 |
--- a/courgette/disassembler_elf_32.cc |
+++ b/courgette/disassembler_elf_32.cc |
@@ -32,6 +32,15 @@ std::vector<Elf32_Half> GetSectionHeaderFileOffsetOrder( |
} // namespace |
+DisassemblerElf32::Elf32RvaVisitor_Rel32::Elf32RvaVisitor_Rel32( |
+ const std::vector<TypedRVA*>& rva_locations) |
+ : VectorRvaVisitor<TypedRVA*>(rva_locations) { |
+} |
+ |
+RVA DisassemblerElf32::Elf32RvaVisitor_Rel32::Get() const { |
+ return (*it_)->rva() + (*it_)->relative_target(); |
+} |
+ |
DisassemblerElf32::DisassemblerElf32(const void* start, size_t length) |
: Disassembler(start, length), |
header_(nullptr), |
@@ -163,12 +172,16 @@ bool DisassemblerElf32::Disassemble(AssemblyProgram* target) { |
if (!ParseAbs32Relocs()) |
return false; |
- if (!ParseRel32RelocsFromSections()) |
+ if (!ParseRel32RelocsFromSections()) // Does not sort rel32 locations. |
return false; |
+ PrecomputeLabels(target); |
+ RemoveUnusedRel32Locations(target); |
+ |
if (!ParseFile(target)) |
return false; |
+ // Finally sort rel32 locations. |
std::sort(rel32_locations_.begin(), |
rel32_locations_.end(), |
TypedRVA::IsLessThanByRVA); |
@@ -179,6 +192,28 @@ bool DisassemblerElf32::Disassemble(AssemblyProgram* target) { |
return true; |
} |
+CheckBool DisassemblerElf32::IsValidTargetRVA(RVA rva) const { |
+ if (rva == kUnassignedRVA) |
+ return false; |
+ |
+ // |rva| is valid if it's contained in any program segment. |
+ for (Elf32_Half segment_id = 0; segment_id < ProgramSegmentHeaderCount(); |
+ ++segment_id) { |
+ const Elf32_Phdr* segment_header = ProgramSegmentHeader(segment_id); |
+ |
+ if (segment_header->p_type != PT_LOAD) |
+ continue; |
+ |
+ Elf32_Addr begin = segment_header->p_vaddr; |
+ Elf32_Addr end = segment_header->p_vaddr + segment_header->p_memsz; |
+ |
+ if (rva >= begin && rva < end) |
+ return true; |
+ } |
+ |
+ return false; |
+} |
+ |
bool DisassemblerElf32::UpdateLength() { |
Elf32_Off result = 0; |
@@ -237,32 +272,11 @@ CheckBool DisassemblerElf32::SectionName(const Elf32_Shdr& shdr, |
return true; |
} |
-CheckBool DisassemblerElf32::IsValidTargetRVA(RVA rva) const { |
- if (rva == kUnassignedRVA) |
- return false; |
- |
- // It's valid if it's contained in any program segment |
- for (Elf32_Half segment_id = 0; segment_id < ProgramSegmentHeaderCount(); |
- ++segment_id) { |
- const Elf32_Phdr* segment_header = ProgramSegmentHeader(segment_id); |
- |
- if (segment_header->p_type != PT_LOAD) |
- continue; |
- |
- Elf32_Addr begin = segment_header->p_vaddr; |
- Elf32_Addr end = segment_header->p_vaddr + segment_header->p_memsz; |
- |
- if (rva >= begin && rva < end) |
- return true; |
- } |
- |
- return false; |
-} |
- |
CheckBool DisassemblerElf32::RVAsToFileOffsets( |
const std::vector<RVA>& rvas, |
std::vector<FileOffset>* file_offsets) { |
file_offsets->clear(); |
+ file_offsets->reserve(rvas.size()); |
for (RVA rva : rvas) { |
FileOffset file_offset = RVAToFileOffset(rva); |
if (file_offset == kNoFileOffset) |
@@ -283,6 +297,24 @@ CheckBool DisassemblerElf32::RVAsToFileOffsets( |
return true; |
} |
+RvaVisitor* DisassemblerElf32::CreateAbs32TargetRvaVisitor() { |
+ return new RvaVisitor_Abs32(abs32_locations_, *this); |
+} |
+ |
+RvaVisitor* DisassemblerElf32::CreateRel32TargetRvaVisitor() { |
+ return new Elf32RvaVisitor_Rel32(rel32_locations_.get()); |
+} |
+ |
+void DisassemblerElf32::RemoveUnusedRel32Locations(AssemblyProgram* program) { |
+ auto cond = [program](const TypedRVA* typed_rva) -> bool { |
+ RVA target_rva = typed_rva->rva() + typed_rva->relative_target(); |
+ return program->FindRel32Label(target_rva) == nullptr; |
+ }; |
+ rel32_locations_.erase( |
+ std::remove_if(rel32_locations_.begin(), rel32_locations_.end(), cond), |
+ rel32_locations_.end()); |
+} |
+ |
CheckBool DisassemblerElf32::ParseFile(AssemblyProgram* program) { |
// Walk all the bytes in the file, whether or not in a section. |
FileOffset file_offset = 0; |
@@ -422,7 +454,9 @@ CheckBool DisassemblerElf32::ParseProgbitsSection( |
RVA target_rva = PointerToTargetRVA(FileOffsetToPointer(file_offset)); |
DCHECK_NE(kNoRVA, target_rva); |
- if (!program->EmitAbs32(program->FindOrMakeAbs32Label(target_rva))) |
+ Label* label = program->FindAbs32Label(target_rva); |
+ CHECK(label); |
+ if (!program->EmitAbs32(label)) |
return false; |
file_offset += sizeof(RVA); |
++(*current_abs_offset); |
@@ -432,12 +466,17 @@ CheckBool DisassemblerElf32::ParseProgbitsSection( |
if (*current_rel != end_rel && |
file_offset == (**current_rel)->file_offset()) { |
uint32_t relative_target = (**current_rel)->relative_target(); |
+ CHECK_EQ(RVA(origin + (file_offset - origin_offset)), |
+ (**current_rel)->rva()); |
// This cast is for 64 bit systems, and is only safe because we |
// are working on 32 bit executables. |
RVA target_rva = (RVA)(origin + (file_offset - origin_offset) + |
relative_target); |
- if (!(**current_rel)->EmitInstruction(program, target_rva)) |
+ Label* label = program->FindRel32Label(target_rva); |
+ CHECK(label); |
+ |
+ if (!(**current_rel)->EmitInstruction(program, label)) |
return false; |
file_offset += (**current_rel)->op_size(); |
++(*current_rel); |