#define DEBUG_TYPE "dwarfdebug"
#include "DIE.h"
#include "DIEHash.h"
#include "DwarfCompileUnit.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/MD5.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
static StringRef getDIEStringAttr(const DIE &Die, uint16_t Attr) {
const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
const DIEAbbrev &Abbrevs = Die.getAbbrev();
for (size_t i = 0; i < Values.size(); ++i) {
if (Abbrevs.getData()[i].getAttribute() == Attr) {
DIEValue *V = Values[i];
assert(isa<DIEString>(V) && "String requested. Not a string.");
DIEString *S = cast<DIEString>(V);
return S->getString();
}
}
return StringRef("");
}
void DIEHash::addString(StringRef Str) {
DEBUG(dbgs() << "Adding string " << Str << " to hash.\n");
Hash.update(Str);
Hash.update(makeArrayRef((uint8_t)'\0'));
}
void DIEHash::addULEB128(uint64_t Value) {
DEBUG(dbgs() << "Adding ULEB128 " << Value << " to hash.\n");
do {
uint8_t Byte = Value & 0x7f;
Value >>= 7;
if (Value != 0)
Byte |= 0x80; Hash.update(Byte);
} while (Value != 0);
}
void DIEHash::addSLEB128(int64_t Value) {
DEBUG(dbgs() << "Adding ULEB128 " << Value << " to hash.\n");
bool More;
do {
uint8_t Byte = Value & 0x7f;
Value >>= 7;
More = !((((Value == 0 ) && ((Byte & 0x40) == 0)) ||
((Value == -1) && ((Byte & 0x40) != 0))));
if (More)
Byte |= 0x80; Hash.update(Byte);
} while (More);
}
void DIEHash::addParentContext(const DIE &Parent) {
DEBUG(dbgs() << "Adding parent context to hash...\n");
SmallVector<const DIE *, 1> Parents;
const DIE *Cur = &Parent;
while (Cur->getTag() != dwarf::DW_TAG_compile_unit) {
Parents.push_back(Cur);
Cur = Cur->getParent();
}
for (SmallVectorImpl<const DIE *>::reverse_iterator I = Parents.rbegin(),
E = Parents.rend();
I != E; ++I) {
const DIE &Die = **I;
addULEB128('C');
addULEB128(Die.getTag());
StringRef Name = getDIEStringAttr(Die, dwarf::DW_AT_name);
DEBUG(dbgs() << "... adding context: " << Name << "\n");
if (!Name.empty())
addString(Name);
}
}
void DIEHash::collectAttributes(const DIE &Die, DIEAttrs &Attrs) {
const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
const DIEAbbrev &Abbrevs = Die.getAbbrev();
#define COLLECT_ATTR(NAME) \
case dwarf::NAME: \
Attrs.NAME.Val = Values[i]; \
Attrs.NAME.Desc = &Abbrevs.getData()[i]; \
break
for (size_t i = 0, e = Values.size(); i != e; ++i) {
DEBUG(dbgs() << "Attribute: "
<< dwarf::AttributeString(Abbrevs.getData()[i].getAttribute())
<< " added.\n");
switch (Abbrevs.getData()[i].getAttribute()) {
COLLECT_ATTR(DW_AT_name);
COLLECT_ATTR(DW_AT_accessibility);
COLLECT_ATTR(DW_AT_address_class);
COLLECT_ATTR(DW_AT_allocated);
COLLECT_ATTR(DW_AT_artificial);
COLLECT_ATTR(DW_AT_associated);
COLLECT_ATTR(DW_AT_binary_scale);
COLLECT_ATTR(DW_AT_bit_offset);
COLLECT_ATTR(DW_AT_bit_size);
COLLECT_ATTR(DW_AT_bit_stride);
COLLECT_ATTR(DW_AT_byte_size);
COLLECT_ATTR(DW_AT_byte_stride);
COLLECT_ATTR(DW_AT_const_expr);
COLLECT_ATTR(DW_AT_const_value);
COLLECT_ATTR(DW_AT_containing_type);
COLLECT_ATTR(DW_AT_count);
COLLECT_ATTR(DW_AT_data_bit_offset);
COLLECT_ATTR(DW_AT_data_location);
COLLECT_ATTR(DW_AT_data_member_location);
COLLECT_ATTR(DW_AT_decimal_scale);
COLLECT_ATTR(DW_AT_decimal_sign);
COLLECT_ATTR(DW_AT_default_value);
COLLECT_ATTR(DW_AT_digit_count);
COLLECT_ATTR(DW_AT_discr);
COLLECT_ATTR(DW_AT_discr_list);
COLLECT_ATTR(DW_AT_discr_value);
COLLECT_ATTR(DW_AT_encoding);
COLLECT_ATTR(DW_AT_enum_class);
COLLECT_ATTR(DW_AT_endianity);
COLLECT_ATTR(DW_AT_explicit);
COLLECT_ATTR(DW_AT_is_optional);
COLLECT_ATTR(DW_AT_location);
COLLECT_ATTR(DW_AT_lower_bound);
COLLECT_ATTR(DW_AT_mutable);
COLLECT_ATTR(DW_AT_ordering);
COLLECT_ATTR(DW_AT_picture_string);
COLLECT_ATTR(DW_AT_prototyped);
COLLECT_ATTR(DW_AT_small);
COLLECT_ATTR(DW_AT_segment);
COLLECT_ATTR(DW_AT_string_length);
COLLECT_ATTR(DW_AT_threads_scaled);
COLLECT_ATTR(DW_AT_upper_bound);
COLLECT_ATTR(DW_AT_use_location);
COLLECT_ATTR(DW_AT_use_UTF8);
COLLECT_ATTR(DW_AT_variable_parameter);
COLLECT_ATTR(DW_AT_virtuality);
COLLECT_ATTR(DW_AT_visibility);
COLLECT_ATTR(DW_AT_vtable_elem_location);
COLLECT_ATTR(DW_AT_type);
default:
break;
}
}
}
void DIEHash::hashShallowTypeReference(dwarf::Attribute Attribute,
const DIE &Entry, StringRef Name) {
addULEB128('N');
addULEB128(Attribute);
if (const DIE *Parent = Entry.getParent())
addParentContext(*Parent);
addULEB128('E');
addString(Name);
}
void DIEHash::hashRepeatedTypeReference(dwarf::Attribute Attribute,
unsigned DieNumber) {
addULEB128('R');
addULEB128(Attribute);
addULEB128(DieNumber);
}
void DIEHash::hashDIEEntry(dwarf::Attribute Attribute, dwarf::Tag Tag,
const DIE &Entry) {
assert(Tag != dwarf::DW_TAG_friend && "No current LLVM clients emit friend "
"tags. Add support here when there's "
"a use case");
if ((Tag == dwarf::DW_TAG_pointer_type ||
Tag == dwarf::DW_TAG_reference_type ||
Tag == dwarf::DW_TAG_rvalue_reference_type ||
Tag == dwarf::DW_TAG_ptr_to_member_type) &&
Attribute == dwarf::DW_AT_type) {
StringRef Name = getDIEStringAttr(Entry, dwarf::DW_AT_name);
if (!Name.empty()) {
hashShallowTypeReference(Attribute, Entry, Name);
return;
}
}
unsigned &DieNumber = Numbering[&Entry];
if (DieNumber) {
hashRepeatedTypeReference(Attribute, DieNumber);
return;
}
addULEB128('T');
addULEB128(Attribute);
DieNumber = Numbering.size();
computeHash(Entry);
}
void DIEHash::hashAttribute(AttrEntry Attr, dwarf::Tag Tag) {
const DIEValue *Value = Attr.Val;
const DIEAbbrevData *Desc = Attr.Desc;
dwarf::Attribute Attribute = Desc->getAttribute();
if (const DIEEntry *EntryAttr = dyn_cast<DIEEntry>(Value)) {
hashDIEEntry(Attribute, Tag, *EntryAttr->getEntry());
return;
}
addULEB128('A');
addULEB128(Attribute);
switch (Desc->getForm()) {
case dwarf::DW_FORM_string:
llvm_unreachable(
"Add support for DW_FORM_string if we ever start emitting them again");
case dwarf::DW_FORM_GNU_str_index:
case dwarf::DW_FORM_strp:
addULEB128(dwarf::DW_FORM_string);
addString(cast<DIEString>(Value)->getString());
break;
case dwarf::DW_FORM_data1:
case dwarf::DW_FORM_data2:
case dwarf::DW_FORM_data4:
case dwarf::DW_FORM_data8:
case dwarf::DW_FORM_udata:
addULEB128(dwarf::DW_FORM_sdata);
addSLEB128((int64_t)cast<DIEInteger>(Value)->getValue());
break;
default:
llvm_unreachable("Add support for additional forms");
}
}
void DIEHash::hashAttributes(const DIEAttrs &Attrs, dwarf::Tag Tag) {
#define ADD_ATTR(ATTR) \
{ \
if (ATTR.Val != 0) \
hashAttribute(ATTR, Tag); \
}
ADD_ATTR(Attrs.DW_AT_name);
ADD_ATTR(Attrs.DW_AT_accessibility);
ADD_ATTR(Attrs.DW_AT_address_class);
ADD_ATTR(Attrs.DW_AT_allocated);
ADD_ATTR(Attrs.DW_AT_artificial);
ADD_ATTR(Attrs.DW_AT_associated);
ADD_ATTR(Attrs.DW_AT_binary_scale);
ADD_ATTR(Attrs.DW_AT_bit_offset);
ADD_ATTR(Attrs.DW_AT_bit_size);
ADD_ATTR(Attrs.DW_AT_bit_stride);
ADD_ATTR(Attrs.DW_AT_byte_size);
ADD_ATTR(Attrs.DW_AT_byte_stride);
ADD_ATTR(Attrs.DW_AT_const_expr);
ADD_ATTR(Attrs.DW_AT_const_value);
ADD_ATTR(Attrs.DW_AT_containing_type);
ADD_ATTR(Attrs.DW_AT_count);
ADD_ATTR(Attrs.DW_AT_data_bit_offset);
ADD_ATTR(Attrs.DW_AT_data_location);
ADD_ATTR(Attrs.DW_AT_data_member_location);
ADD_ATTR(Attrs.DW_AT_decimal_scale);
ADD_ATTR(Attrs.DW_AT_decimal_sign);
ADD_ATTR(Attrs.DW_AT_default_value);
ADD_ATTR(Attrs.DW_AT_digit_count);
ADD_ATTR(Attrs.DW_AT_discr);
ADD_ATTR(Attrs.DW_AT_discr_list);
ADD_ATTR(Attrs.DW_AT_discr_value);
ADD_ATTR(Attrs.DW_AT_encoding);
ADD_ATTR(Attrs.DW_AT_enum_class);
ADD_ATTR(Attrs.DW_AT_endianity);
ADD_ATTR(Attrs.DW_AT_explicit);
ADD_ATTR(Attrs.DW_AT_is_optional);
ADD_ATTR(Attrs.DW_AT_location);
ADD_ATTR(Attrs.DW_AT_lower_bound);
ADD_ATTR(Attrs.DW_AT_mutable);
ADD_ATTR(Attrs.DW_AT_ordering);
ADD_ATTR(Attrs.DW_AT_picture_string);
ADD_ATTR(Attrs.DW_AT_prototyped);
ADD_ATTR(Attrs.DW_AT_small);
ADD_ATTR(Attrs.DW_AT_segment);
ADD_ATTR(Attrs.DW_AT_string_length);
ADD_ATTR(Attrs.DW_AT_threads_scaled);
ADD_ATTR(Attrs.DW_AT_upper_bound);
ADD_ATTR(Attrs.DW_AT_use_location);
ADD_ATTR(Attrs.DW_AT_use_UTF8);
ADD_ATTR(Attrs.DW_AT_variable_parameter);
ADD_ATTR(Attrs.DW_AT_virtuality);
ADD_ATTR(Attrs.DW_AT_visibility);
ADD_ATTR(Attrs.DW_AT_vtable_elem_location);
ADD_ATTR(Attrs.DW_AT_type);
}
void DIEHash::addAttributes(const DIE &Die) {
DIEAttrs Attrs = {};
collectAttributes(Die, Attrs);
hashAttributes(Attrs, Die.getTag());
}
void DIEHash::hashNestedType(const DIE &Die, StringRef Name) {
addULEB128('S');
addULEB128(Die.getTag());
addString(Name);
}
void DIEHash::computeHash(const DIE &Die) {
addULEB128('D');
addULEB128(Die.getTag());
addAttributes(Die);
for (std::vector<DIE *>::const_iterator I = Die.getChildren().begin(),
E = Die.getChildren().end();
I != E; ++I) {
if (isType((*I)->getTag()) || (*I)->getTag() == dwarf::DW_TAG_subprogram) {
StringRef Name = getDIEStringAttr(**I, dwarf::DW_AT_name);
if (!Name.empty()) {
hashNestedType(**I, Name);
continue;
}
}
computeHash(**I);
}
Hash.update(makeArrayRef((uint8_t)'\0'));
}
uint64_t DIEHash::computeDIEODRSignature(const DIE &Die) {
if (const DIE *Parent = Die.getParent())
addParentContext(*Parent);
addULEB128(Die.getTag());
addString(getDIEStringAttr(Die, dwarf::DW_AT_name));
MD5::MD5Result Result;
Hash.final(Result);
return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
}
uint64_t DIEHash::computeCUSignature(const DIE &Die) {
Numbering.clear();
Numbering[&Die] = 1;
computeHash(Die);
MD5::MD5Result Result;
Hash.final(Result);
return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
}
uint64_t DIEHash::computeTypeSignature(const DIE &Die) {
Numbering.clear();
Numbering[&Die] = 1;
if (const DIE *Parent = Die.getParent())
addParentContext(*Parent);
computeHash(Die);
MD5::MD5Result Result;
Hash.final(Result);
return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
}