llvm-project/lldb/source/Expression/IRInterpreter.cpp

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//===-- IRInterpreter.cpp ---------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Core/DataEncoder.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/ValueObjectConstResult.h"
#include "lldb/Expression/ClangExpressionDeclMap.h"
#include "lldb/Expression/IRForTarget.h"
#include "lldb/Expression/IRInterpreter.h"
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/Instructions.h"
#include "llvm/Module.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetData.h"
#include <map>
using namespace llvm;
IRInterpreter::IRInterpreter(lldb_private::ClangExpressionDeclMap &decl_map,
lldb_private::Stream *error_stream) :
m_decl_map(decl_map),
m_error_stream(error_stream)
{
}
IRInterpreter::~IRInterpreter()
{
}
static std::string
PrintValue(const Value *value, bool truncate = false)
{
std::string s;
raw_string_ostream rso(s);
value->print(rso);
rso.flush();
if (truncate)
s.resize(s.length() - 1);
size_t offset;
while ((offset = s.find('\n')) != s.npos)
s.erase(offset, 1);
while (s[0] == ' ' || s[0] == '\t')
s.erase(0, 1);
return s;
}
static std::string
PrintType(const Type *type, bool truncate = false)
{
std::string s;
raw_string_ostream rso(s);
type->print(rso);
rso.flush();
if (truncate)
s.resize(s.length() - 1);
return s;
}
typedef lldb::SharedPtr <lldb_private::DataEncoder>::Type DataEncoderSP;
typedef lldb::SharedPtr <lldb_private::DataExtractor>::Type DataExtractorSP;
class Memory
{
public:
typedef uint32_t index_t;
struct Allocation
{
// m_virtual_address is always the address of the variable in the virtual memory
// space provided by Memory.
//
// m_origin is always non-NULL and describes the source of the data (possibly
// m_data if this allocation is the authoritative source).
//
// Possible value configurations:
//
// Allocation type getValueType() getContextType() m_origin->GetScalar() m_data
// =========================================================================================================================
// FileAddress eValueTypeFileAddress eContextTypeInvalid A location in a binary NULL
// image
//
// LoadAddress eValueTypeLoadAddress eContextTypeInvalid A location in the target's NULL
// virtual memory
//
// Alloca eValueTypeHostAddress eContextTypeInvalid == m_data->GetBytes() Deleted at end of
// execution
//
// PersistentVar eValueTypeHostAddress eContextTypeClangType A persistent variable's NULL
// location in LLDB's memory
//
// Register [ignored] eContextTypeRegister [ignored] Flushed to the register
// at the end of execution
lldb::addr_t m_virtual_address;
size_t m_extent;
lldb_private::Value m_origin;
lldb::DataBufferSP m_data;
Allocation (lldb::addr_t virtual_address,
size_t extent,
lldb::DataBufferSP data) :
m_virtual_address(virtual_address),
m_extent(extent),
m_data(data)
{
}
Allocation (const Allocation &allocation) :
m_virtual_address(allocation.m_virtual_address),
m_extent(allocation.m_extent),
m_origin(allocation.m_origin),
m_data(allocation.m_data)
{
}
};
typedef lldb::SharedPtr <Allocation>::Type AllocationSP;
struct Region
{
AllocationSP m_allocation;
uint64_t m_base;
uint64_t m_extent;
Region () :
m_allocation(),
m_base(0),
m_extent(0)
{
}
Region (AllocationSP allocation, uint64_t base, uint64_t extent) :
m_allocation(allocation),
m_base(base),
m_extent(extent)
{
}
Region (const Region &region) :
m_allocation(region.m_allocation),
m_base(region.m_base),
m_extent(region.m_extent)
{
}
bool IsValid ()
{
return m_allocation != NULL;
}
bool IsInvalid ()
{
return m_allocation == NULL;
}
};
typedef std::vector <AllocationSP> MemoryMap;
private:
lldb::addr_t m_addr_base;
lldb::addr_t m_addr_max;
MemoryMap m_memory;
lldb::ByteOrder m_byte_order;
lldb::addr_t m_addr_byte_size;
TargetData &m_target_data;
lldb_private::ClangExpressionDeclMap &m_decl_map;
MemoryMap::iterator LookupInternal (lldb::addr_t addr)
{
for (MemoryMap::iterator i = m_memory.begin(), e = m_memory.end();
i != e;
++i)
{
if ((*i)->m_virtual_address <= addr &&
(*i)->m_virtual_address + (*i)->m_extent > addr)
return i;
}
return m_memory.end();
}
public:
Memory (TargetData &target_data,
lldb_private::ClangExpressionDeclMap &decl_map,
lldb::addr_t alloc_start,
lldb::addr_t alloc_max) :
m_addr_base(alloc_start),
m_addr_max(alloc_max),
m_target_data(target_data),
m_decl_map(decl_map)
{
m_byte_order = (target_data.isLittleEndian() ? lldb::eByteOrderLittle : lldb::eByteOrderBig);
m_addr_byte_size = (target_data.getPointerSize());
}
Region Malloc (size_t size, size_t align)
{
lldb::DataBufferSP data(new lldb_private::DataBufferHeap(size, 0));
if (data)
{
index_t index = m_memory.size();
const size_t mask = (align - 1);
m_addr_base += mask;
m_addr_base &= ~mask;
if (m_addr_base + size < m_addr_base ||
m_addr_base + size > m_addr_max)
return Region();
uint64_t base = m_addr_base;
m_memory.push_back(AllocationSP(new Allocation(base, size, data)));
m_addr_base += size;
AllocationSP alloc = m_memory[index];
alloc->m_origin.GetScalar() = (unsigned long long)data->GetBytes();
alloc->m_origin.SetContext(lldb_private::Value::eContextTypeInvalid, NULL);
alloc->m_origin.SetValueType(lldb_private::Value::eValueTypeHostAddress);
return Region(alloc, base, size);
}
return Region();
}
Region Malloc (Type *type)
{
return Malloc (m_target_data.getTypeAllocSize(type),
m_target_data.getPrefTypeAlignment(type));
}
Region Place (Type *type, lldb::addr_t base, lldb_private::Value &value)
{
index_t index = m_memory.size();
size_t size = m_target_data.getTypeAllocSize(type);
m_memory.push_back(AllocationSP(new Allocation(base, size, lldb::DataBufferSP())));
AllocationSP alloc = m_memory[index];
alloc->m_origin = value;
return Region(alloc, base, size);
}
void Free (lldb::addr_t addr)
{
MemoryMap::iterator i = LookupInternal (addr);
if (i != m_memory.end())
m_memory.erase(i);
}
Region Lookup (lldb::addr_t addr, Type *type)
{
MemoryMap::iterator i = LookupInternal(addr);
if (i == m_memory.end())
return Region();
size_t size = m_target_data.getTypeStoreSize(type);
return Region(*i, addr, size);
}
DataEncoderSP GetEncoder (Region region)
{
if (region.m_allocation->m_origin.GetValueType() != lldb_private::Value::eValueTypeHostAddress)
return DataEncoderSP();
lldb::DataBufferSP buffer = region.m_allocation->m_data;
if (!buffer)
return DataEncoderSP();
size_t base_offset = (size_t)(region.m_base - region.m_allocation->m_virtual_address);
return DataEncoderSP(new lldb_private::DataEncoder(buffer->GetBytes() + base_offset, region.m_extent, m_byte_order, m_addr_byte_size));
}
DataExtractorSP GetExtractor (Region region)
{
if (region.m_allocation->m_origin.GetValueType() != lldb_private::Value::eValueTypeHostAddress)
return DataExtractorSP();
lldb::DataBufferSP buffer = region.m_allocation->m_data;
size_t base_offset = (size_t)(region.m_base - region.m_allocation->m_virtual_address);
if (buffer)
return DataExtractorSP(new lldb_private::DataExtractor(buffer->GetBytes() + base_offset, region.m_extent, m_byte_order, m_addr_byte_size));
else
return DataExtractorSP(new lldb_private::DataExtractor((uint8_t*)region.m_allocation->m_origin.GetScalar().ULongLong() + base_offset, region.m_extent, m_byte_order, m_addr_byte_size));
}
lldb_private::Value GetAccessTarget(lldb::addr_t addr)
{
MemoryMap::iterator i = LookupInternal(addr);
if (i == m_memory.end())
return lldb_private::Value();
lldb_private::Value target = (*i)->m_origin;
if (target.GetContextType() == lldb_private::Value::eContextTypeRegisterInfo)
{
target.SetContext(lldb_private::Value::eContextTypeInvalid, NULL);
target.SetValueType(lldb_private::Value::eValueTypeHostAddress);
target.GetScalar() = (unsigned long long)(*i)->m_data->GetBytes();
}
target.GetScalar() += (addr - (*i)->m_virtual_address);
return target;
}
bool Write (lldb::addr_t addr, const uint8_t *data, size_t length)
{
lldb_private::Value target = GetAccessTarget(addr);
return m_decl_map.WriteTarget(target, data, length);
}
bool Read (uint8_t *data, lldb::addr_t addr, size_t length)
{
lldb_private::Value source = GetAccessTarget(addr);
return m_decl_map.ReadTarget(data, source, length);
}
bool WriteToRawPtr (lldb::addr_t addr, const uint8_t *data, size_t length)
{
lldb_private::Value target = m_decl_map.WrapBareAddress(addr);
return m_decl_map.WriteTarget(target, data, length);
}
bool ReadFromRawPtr (uint8_t *data, lldb::addr_t addr, size_t length)
{
lldb_private::Value source = m_decl_map.WrapBareAddress(addr);
return m_decl_map.ReadTarget(data, source, length);
}
std::string PrintData (lldb::addr_t addr, size_t length)
{
lldb_private::Value target = GetAccessTarget(addr);
lldb_private::DataBufferHeap buf(length, 0);
if (!m_decl_map.ReadTarget(buf.GetBytes(), target, length))
return std::string("<couldn't read data>");
lldb_private::StreamString ss;
for (size_t i = 0; i < length; i++)
{
if ((!(i & 0xf)) && i)
ss.Printf("%02hhx - ", buf.GetBytes()[i]);
else
ss.Printf("%02hhx ", buf.GetBytes()[i]);
}
return ss.GetString();
}
std::string SummarizeRegion (Region &region)
{
lldb_private::StreamString ss;
lldb_private::Value base = GetAccessTarget(region.m_base);
ss.Printf("%llx [%s - %s %llx]",
region.m_base,
lldb_private::Value::GetValueTypeAsCString(base.GetValueType()),
lldb_private::Value::GetContextTypeAsCString(base.GetContextType()),
base.GetScalar().ULongLong());
ss.Printf(" %s", PrintData(region.m_base, region.m_extent).c_str());
return ss.GetString();
}
};
class InterpreterStackFrame
{
public:
typedef std::map <const Value*, Memory::Region> ValueMap;
ValueMap m_values;
Memory &m_memory;
TargetData &m_target_data;
lldb_private::ClangExpressionDeclMap &m_decl_map;
const BasicBlock *m_bb;
BasicBlock::const_iterator m_ii;
BasicBlock::const_iterator m_ie;
lldb::ByteOrder m_byte_order;
size_t m_addr_byte_size;
InterpreterStackFrame (TargetData &target_data,
Memory &memory,
lldb_private::ClangExpressionDeclMap &decl_map) :
m_memory (memory),
m_target_data (target_data),
m_decl_map (decl_map)
{
m_byte_order = (target_data.isLittleEndian() ? lldb::eByteOrderLittle : lldb::eByteOrderBig);
m_addr_byte_size = (target_data.getPointerSize());
}
void Jump (const BasicBlock *bb)
{
m_bb = bb;
m_ii = m_bb->begin();
m_ie = m_bb->end();
}
bool Cache (Memory::AllocationSP allocation, Type *type)
{
if (allocation->m_origin.GetContextType() != lldb_private::Value::eContextTypeRegisterInfo)
return false;
return m_decl_map.ReadTarget(allocation->m_data->GetBytes(), allocation->m_origin, allocation->m_data->GetByteSize());
}
std::string SummarizeValue (const Value *value)
{
lldb_private::StreamString ss;
ss.Printf("%s", PrintValue(value).c_str());
ValueMap::iterator i = m_values.find(value);
if (i != m_values.end())
{
Memory::Region region = i->second;
ss.Printf(" %s", m_memory.SummarizeRegion(region).c_str());
}
return ss.GetString();
}
bool AssignToMatchType (lldb_private::Scalar &scalar, uint64_t u64value, Type *type)
{
size_t type_size = m_target_data.getTypeStoreSize(type);
switch (type_size)
{
case 1:
scalar = (uint8_t)u64value;
break;
case 2:
scalar = (uint16_t)u64value;
break;
case 4:
scalar = (uint32_t)u64value;
break;
case 8:
scalar = (uint64_t)u64value;
break;
default:
return false;
}
return true;
}
bool EvaluateValue (lldb_private::Scalar &scalar, const Value *value, Module &module)
{
const Constant *constant = dyn_cast<Constant>(value);
if (constant)
{
if (const ConstantInt *constant_int = dyn_cast<ConstantInt>(constant))
{
return AssignToMatchType(scalar, constant_int->getLimitedValue(), value->getType());
}
}
else
{
Memory::Region region = ResolveValue(value, module);
DataExtractorSP value_extractor = m_memory.GetExtractor(region);
if (!value_extractor)
return false;
size_t value_size = m_target_data.getTypeStoreSize(value->getType());
uint32_t offset = 0;
uint64_t u64value = value_extractor->GetMaxU64(&offset, value_size);
return AssignToMatchType(scalar, u64value, value->getType());
}
return false;
}
bool AssignValue (const Value *value, lldb_private::Scalar &scalar, Module &module)
{
Memory::Region region = ResolveValue (value, module);
lldb_private::Scalar cast_scalar;
if (!AssignToMatchType(cast_scalar, scalar.GetRawBits64(0), value->getType()))
return false;
lldb_private::DataBufferHeap buf(cast_scalar.GetByteSize(), 0);
lldb_private::Error err;
if (!cast_scalar.GetAsMemoryData(buf.GetBytes(), buf.GetByteSize(), m_byte_order, err))
return false;
DataEncoderSP region_encoder = m_memory.GetEncoder(region);
memcpy(region_encoder->GetDataStart(), buf.GetBytes(), buf.GetByteSize());
return true;
}
bool ResolveConstant (Memory::Region &region, const Constant *constant)
{
size_t constant_size = m_target_data.getTypeStoreSize(constant->getType());
if (const ConstantInt *constant_int = dyn_cast<ConstantInt>(constant))
{
const uint64_t *raw_data = constant_int->getValue().getRawData();
return m_memory.Write(region.m_base, (const uint8_t*)raw_data, constant_size);
}
else if (const ConstantFP *constant_fp = dyn_cast<ConstantFP>(constant))
{
const uint64_t *raw_data = constant_fp->getValueAPF().bitcastToAPInt().getRawData();
return m_memory.Write(region.m_base, (const uint8_t*)raw_data, constant_size);
}
else if (const ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(constant))
{
switch (constant_expr->getOpcode())
{
default:
return false;
case Instruction::IntToPtr:
case Instruction::BitCast:
return ResolveConstant(region, constant_expr->getOperand(0));
}
}
return false;
}
Memory::Region ResolveValue (const Value *value, Module &module)
{
ValueMap::iterator i = m_values.find(value);
if (i != m_values.end())
return i->second;
const GlobalValue *global_value = dyn_cast<GlobalValue>(value);
// If the variable is indirected through the argument
// array then we need to build an extra level of indirection
// for it. This is the default; only magic arguments like
// "this", "self", and "_cmd" are direct.
bool indirect_variable = true;
// Attempt to resolve the value using the program's data.
// If it is, the values to be created are:
//
// data_region - a region of memory in which the variable's data resides.
// ref_region - a region of memory in which its address (i.e., &var) resides.
// In the JIT case, this region would be a member of the struct passed in.
// pointer_region - a region of memory in which the address of the pointer
// resides. This is an IR-level variable.
do
{
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
lldb_private::Value resolved_value;
if (global_value)
{
clang::NamedDecl *decl = IRForTarget::DeclForGlobal(global_value, &module);
if (!decl)
break;
if (isa<clang::FunctionDecl>(decl))
{
if (log)
log->Printf("The interpreter does not handle function pointers at the moment");
return Memory::Region();
}
resolved_value = m_decl_map.LookupDecl(decl);
}
else
{
// Special-case "this", "self", and "_cmd"
std::string name_str = value->getNameStr();
if (name_str == "this" ||
name_str == "self" ||
name_str == "_cmd")
resolved_value = m_decl_map.GetSpecialValue(lldb_private::ConstString(name_str.c_str()));
indirect_variable = false;
}
if (resolved_value.GetScalar().GetType() != lldb_private::Scalar::e_void)
{
if (resolved_value.GetContextType() == lldb_private::Value::eContextTypeRegisterInfo)
{
Memory::Region data_region = m_memory.Malloc(value->getType());
data_region.m_allocation->m_origin = resolved_value;
Memory::Region ref_region = m_memory.Malloc(value->getType());
Memory::Region pointer_region;
if (indirect_variable)
pointer_region = m_memory.Malloc(value->getType());
if (!Cache(data_region.m_allocation, value->getType()))
return Memory::Region();
if (ref_region.IsInvalid())
return Memory::Region();
if (pointer_region.IsInvalid() && indirect_variable)
return Memory::Region();
DataEncoderSP ref_encoder = m_memory.GetEncoder(ref_region);
if (ref_encoder->PutAddress(0, data_region.m_base) == UINT32_MAX)
return Memory::Region();
if (indirect_variable)
{
DataEncoderSP pointer_encoder = m_memory.GetEncoder(pointer_region);
if (pointer_encoder->PutAddress(0, ref_region.m_base) == UINT32_MAX)
return Memory::Region();
m_values[value] = pointer_region;
return pointer_region;
}
else
{
m_values[value] = ref_region;
return ref_region;
}
}
else
{
Memory::Region data_region = m_memory.Place(value->getType(), resolved_value.GetScalar().ULongLong(), resolved_value);
Memory::Region ref_region = m_memory.Malloc(value->getType());
Memory::Region pointer_region;
if (indirect_variable)
pointer_region = m_memory.Malloc(value->getType());
if (ref_region.IsInvalid())
return Memory::Region();
if (pointer_region.IsInvalid() && indirect_variable)
return Memory::Region();
DataEncoderSP ref_encoder = m_memory.GetEncoder(ref_region);
if (ref_encoder->PutAddress(0, data_region.m_base) == UINT32_MAX)
return Memory::Region();
if (indirect_variable)
{
DataEncoderSP pointer_encoder = m_memory.GetEncoder(pointer_region);
if (pointer_encoder->PutAddress(0, ref_region.m_base) == UINT32_MAX)
return Memory::Region();
m_values[value] = pointer_region;
}
if (log)
{
log->Printf("Made an allocation for %s", PrintValue(value).c_str());
log->Printf(" Data contents : %s", m_memory.PrintData(data_region.m_base, data_region.m_extent).c_str());
log->Printf(" Data region : %llx", (unsigned long long)data_region.m_base);
log->Printf(" Ref region : %llx", (unsigned long long)ref_region.m_base);
if (indirect_variable)
log->Printf(" Pointer region : %llx", (unsigned long long)pointer_region.m_base);
}
if (indirect_variable)
return pointer_region;
else
return ref_region;
}
}
}
while(0);
// Fall back and allocate space [allocation type Alloca]
Type *type = value->getType();
lldb::ValueSP backing_value(new lldb_private::Value);
Memory::Region data_region = m_memory.Malloc(type);
data_region.m_allocation->m_origin.GetScalar() = (unsigned long long)data_region.m_allocation->m_data->GetBytes();
data_region.m_allocation->m_origin.SetContext(lldb_private::Value::eContextTypeInvalid, NULL);
data_region.m_allocation->m_origin.SetValueType(lldb_private::Value::eValueTypeHostAddress);
const Constant *constant = dyn_cast<Constant>(value);
do
{
if (!constant)
break;
if (!ResolveConstant (data_region, constant))
return Memory::Region();
}
while(0);
m_values[value] = data_region;
return data_region;
}
bool ConstructResult (lldb::ClangExpressionVariableSP &result,
const GlobalValue *result_value,
const lldb_private::ConstString &result_name,
lldb_private::TypeFromParser result_type,
Module &module)
{
// The result_value resolves to P, a pointer to a region R containing the result data.
// If the result variable is a reference, the region R contains a pointer to the result R_final in the original process.
if (!result_value)
return true; // There was no slot for a result the expression doesn't return one.
ValueMap::iterator i = m_values.find(result_value);
if (i == m_values.end())
return false; // There was a slot for the result, but we didn't write into it.
Memory::Region P = i->second;
DataExtractorSP P_extractor = m_memory.GetExtractor(P);
if (!P_extractor)
return false;
Type *pointer_ty = result_value->getType();
PointerType *pointer_ptr_ty = dyn_cast<PointerType>(pointer_ty);
if (!pointer_ptr_ty)
return false;
Type *R_ty = pointer_ptr_ty->getElementType();
uint32_t offset = 0;
lldb::addr_t pointer = P_extractor->GetAddress(&offset);
Memory::Region R = m_memory.Lookup(pointer, R_ty);
if (R.m_allocation->m_origin.GetValueType() != lldb_private::Value::eValueTypeHostAddress ||
!R.m_allocation->m_data)
return false;
lldb_private::Value base;
bool transient = false;
bool maybe_make_load = false;
if (m_decl_map.ResultIsReference(result_name))
{
PointerType *R_ptr_ty = dyn_cast<PointerType>(R_ty);
if (!R_ptr_ty)
return false;
Type *R_final_ty = R_ptr_ty->getElementType();
DataExtractorSP R_extractor = m_memory.GetExtractor(R);
if (!R_extractor)
return false;
offset = 0;
lldb::addr_t R_pointer = R_extractor->GetAddress(&offset);
Memory::Region R_final = m_memory.Lookup(R_pointer, R_final_ty);
if (R_final.m_allocation)
{
if (R_final.m_allocation->m_data)
transient = true; // this is a stack allocation
base = R_final.m_allocation->m_origin;
base.GetScalar() += (R_final.m_base - R_final.m_allocation->m_virtual_address);
}
else
{
// We got a bare pointer. We are going to treat it as a load address
// or a file address, letting decl_map make the choice based on whether
// or not a process exists.
base.SetContext(lldb_private::Value::eContextTypeInvalid, NULL);
base.SetValueType(lldb_private::Value::eValueTypeFileAddress);
base.GetScalar() = (unsigned long long)R_pointer;
maybe_make_load = true;
}
}
else
{
base.SetContext(lldb_private::Value::eContextTypeInvalid, NULL);
base.SetValueType(lldb_private::Value::eValueTypeHostAddress);
base.GetScalar() = (unsigned long long)R.m_allocation->m_data->GetBytes() + (R.m_base - R.m_allocation->m_virtual_address);
}
return m_decl_map.CompleteResultVariable (result, base, result_name, result_type, transient, maybe_make_load);
}
};
bool
IRInterpreter::maybeRunOnFunction (lldb::ClangExpressionVariableSP &result,
const lldb_private::ConstString &result_name,
lldb_private::TypeFromParser result_type,
Function &llvm_function,
Module &llvm_module)
{
if (supportsFunction (llvm_function))
return runOnFunction(result,
result_name,
result_type,
llvm_function,
llvm_module);
else
return false;
}
bool
IRInterpreter::supportsFunction (Function &llvm_function)
{
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
for (Function::iterator bbi = llvm_function.begin(), bbe = llvm_function.end();
bbi != bbe;
++bbi)
{
for (BasicBlock::iterator ii = bbi->begin(), ie = bbi->end();
ii != ie;
++ii)
{
switch (ii->getOpcode())
{
default:
{
if (log)
log->Printf("Unsupported instruction: %s", PrintValue(ii).c_str());
return false;
}
case Instruction::Add:
case Instruction::Alloca:
case Instruction::BitCast:
case Instruction::Br:
case Instruction::GetElementPtr:
break;
case Instruction::ICmp:
{
ICmpInst *icmp_inst = dyn_cast<ICmpInst>(ii);
if (!icmp_inst)
return false;
switch (icmp_inst->getPredicate())
{
default:
{
if (log)
log->Printf("Unsupported ICmp predicate: %s", PrintValue(ii).c_str());
return false;
}
case CmpInst::ICMP_EQ:
case CmpInst::ICMP_NE:
case CmpInst::ICMP_UGT:
case CmpInst::ICMP_UGE:
case CmpInst::ICMP_ULT:
case CmpInst::ICMP_ULE:
case CmpInst::ICMP_SGT:
case CmpInst::ICMP_SGE:
case CmpInst::ICMP_SLT:
case CmpInst::ICMP_SLE:
break;
}
}
break;
case Instruction::IntToPtr:
case Instruction::Load:
case Instruction::Mul:
case Instruction::Ret:
case Instruction::SDiv:
case Instruction::Store:
case Instruction::Sub:
case Instruction::UDiv:
break;
}
}
}
return true;
}
bool
IRInterpreter::runOnFunction (lldb::ClangExpressionVariableSP &result,
const lldb_private::ConstString &result_name,
lldb_private::TypeFromParser result_type,
Function &llvm_function,
Module &llvm_module)
{
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
lldb_private::ClangExpressionDeclMap::TargetInfo target_info = m_decl_map.GetTargetInfo();
if (!target_info.IsValid())
return false;
lldb::addr_t alloc_min;
lldb::addr_t alloc_max;
switch (target_info.address_byte_size)
{
default:
return false;
case 4:
alloc_min = 0x00001000llu;
alloc_max = 0x0000ffffllu;
break;
case 8:
alloc_min = 0x0000000000001000llu;
alloc_max = 0x000000000000ffffllu;
break;
}
TargetData target_data(&llvm_module);
if (target_data.getPointerSize() != target_info.address_byte_size)
return false;
if (target_data.isLittleEndian() != (target_info.byte_order == lldb::eByteOrderLittle))
return false;
Memory memory(target_data, m_decl_map, alloc_min, alloc_max);
InterpreterStackFrame frame(target_data, memory, m_decl_map);
uint32_t num_insts = 0;
frame.Jump(llvm_function.begin());
while (frame.m_ii != frame.m_ie && (++num_insts < 4096))
{
const Instruction *inst = frame.m_ii;
if (log)
log->Printf("Interpreting %s", PrintValue(inst).c_str());
switch (inst->getOpcode())
{
default:
break;
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::SDiv:
case Instruction::UDiv:
{
const BinaryOperator *bin_op = dyn_cast<BinaryOperator>(inst);
if (!bin_op)
{
if (log)
log->Printf("getOpcode() returns %s, but instruction is not a BinaryOperator", inst->getOpcodeName());
return false;
}
Value *lhs = inst->getOperand(0);
Value *rhs = inst->getOperand(1);
lldb_private::Scalar L;
lldb_private::Scalar R;
if (!frame.EvaluateValue(L, lhs, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(lhs).c_str());
return false;
}
if (!frame.EvaluateValue(R, rhs, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(rhs).c_str());
return false;
}
lldb_private::Scalar result;
switch (inst->getOpcode())
{
default:
break;
case Instruction::Add:
result = L + R;
break;
case Instruction::Mul:
result = L * R;
break;
case Instruction::Sub:
result = L - R;
break;
case Instruction::SDiv:
result = L / R;
break;
case Instruction::UDiv:
result = L.GetRawBits64(0) / R.GetRawBits64(1);
break;
}
frame.AssignValue(inst, result, llvm_module);
if (log)
{
log->Printf("Interpreted a %s", inst->getOpcodeName());
log->Printf(" L : %s", frame.SummarizeValue(lhs).c_str());
log->Printf(" R : %s", frame.SummarizeValue(rhs).c_str());
log->Printf(" = : %s", frame.SummarizeValue(inst).c_str());
}
}
break;
case Instruction::Alloca:
{
const AllocaInst *alloca_inst = dyn_cast<AllocaInst>(inst);
if (!alloca_inst)
{
if (log)
log->Printf("getOpcode() returns Alloca, but instruction is not an AllocaInst");
return false;
}
if (alloca_inst->isArrayAllocation())
{
if (log)
log->Printf("AllocaInsts are not handled if isArrayAllocation() is true");
return false;
}
// The semantics of Alloca are:
// Create a region R of virtual memory of type T, backed by a data buffer
// Create a region P of virtual memory of type T*, backed by a data buffer
// Write the virtual address of R into P
Type *T = alloca_inst->getAllocatedType();
Type *Tptr = alloca_inst->getType();
Memory::Region R = memory.Malloc(T);
if (R.IsInvalid())
{
if (log)
log->Printf("Couldn't allocate memory for an AllocaInst");
return false;
}
Memory::Region P = memory.Malloc(Tptr);
if (P.IsInvalid())
{
if (log)
log->Printf("Couldn't allocate the result pointer for an AllocaInst");
return false;
}
DataEncoderSP P_encoder = memory.GetEncoder(P);
if (P_encoder->PutAddress(0, R.m_base) == UINT32_MAX)
{
if (log)
log->Printf("Couldn't write the reseult pointer for an AllocaInst");
return false;
}
frame.m_values[alloca_inst] = P;
if (log)
{
log->Printf("Interpreted an AllocaInst");
log->Printf(" R : %s", memory.SummarizeRegion(R).c_str());
log->Printf(" P : %s", frame.SummarizeValue(alloca_inst).c_str());
}
}
break;
case Instruction::BitCast:
{
const BitCastInst *bit_cast_inst = dyn_cast<BitCastInst>(inst);
if (!bit_cast_inst)
{
if (log)
log->Printf("getOpcode() returns BitCast, but instruction is not a BitCastInst");
return false;
}
Value *source = bit_cast_inst->getOperand(0);
lldb_private::Scalar S;
if (!frame.EvaluateValue(S, source, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(source).c_str());
return false;
}
frame.AssignValue(inst, S, llvm_module);
}
break;
case Instruction::Br:
{
const BranchInst *br_inst = dyn_cast<BranchInst>(inst);
if (!br_inst)
{
if (log)
log->Printf("getOpcode() returns Br, but instruction is not a BranchInst");
return false;
}
if (br_inst->isConditional())
{
Value *condition = br_inst->getCondition();
lldb_private::Scalar C;
if (!frame.EvaluateValue(C, condition, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(condition).c_str());
return false;
}
if (C.GetRawBits64(0))
frame.Jump(br_inst->getSuccessor(0));
else
frame.Jump(br_inst->getSuccessor(1));
if (log)
{
log->Printf("Interpreted a BrInst with a condition");
log->Printf(" cond : %s", frame.SummarizeValue(condition).c_str());
}
}
else
{
frame.Jump(br_inst->getSuccessor(0));
if (log)
{
log->Printf("Interpreted a BrInst with no condition");
}
}
}
continue;
case Instruction::GetElementPtr:
{
const GetElementPtrInst *gep_inst = dyn_cast<GetElementPtrInst>(inst);
if (!gep_inst)
{
if (log)
log->Printf("getOpcode() returns GetElementPtr, but instruction is not a GetElementPtrInst");
return false;
}
const Value *pointer_operand = gep_inst->getPointerOperand();
Type *pointer_type = pointer_operand->getType();
lldb_private::Scalar P;
if (!frame.EvaluateValue(P, pointer_operand, llvm_module))
return false;
SmallVector <Value *, 8> indices (gep_inst->idx_begin(),
gep_inst->idx_end());
uint64_t offset = target_data.getIndexedOffset(pointer_type, indices);
lldb_private::Scalar Poffset = P + offset;
frame.AssignValue(inst, Poffset, llvm_module);
if (log)
{
log->Printf("Interpreted a GetElementPtrInst");
log->Printf(" P : %s", frame.SummarizeValue(pointer_operand).c_str());
log->Printf(" Poffset : %s", frame.SummarizeValue(inst).c_str());
}
}
break;
case Instruction::ICmp:
{
const ICmpInst *icmp_inst = dyn_cast<ICmpInst>(inst);
if (!icmp_inst)
{
if (log)
log->Printf("getOpcode() returns ICmp, but instruction is not an ICmpInst");
return false;
}
CmpInst::Predicate predicate = icmp_inst->getPredicate();
Value *lhs = inst->getOperand(0);
Value *rhs = inst->getOperand(1);
lldb_private::Scalar L;
lldb_private::Scalar R;
if (!frame.EvaluateValue(L, lhs, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(lhs).c_str());
return false;
}
if (!frame.EvaluateValue(R, rhs, llvm_module))
{
if (log)
log->Printf("Couldn't evaluate %s", PrintValue(rhs).c_str());
return false;
}
lldb_private::Scalar result;
switch (predicate)
{
default:
return false;
case CmpInst::ICMP_EQ:
result = (L == R);
break;
case CmpInst::ICMP_NE:
result = (L != R);
break;
case CmpInst::ICMP_UGT:
result = (L.GetRawBits64(0) > R.GetRawBits64(0));
break;
case CmpInst::ICMP_UGE:
result = (L.GetRawBits64(0) >= R.GetRawBits64(0));
break;
case CmpInst::ICMP_ULT:
result = (L.GetRawBits64(0) < R.GetRawBits64(0));
break;
case CmpInst::ICMP_ULE:
result = (L.GetRawBits64(0) <= R.GetRawBits64(0));
break;
case CmpInst::ICMP_SGT:
result = (L > R);
break;
case CmpInst::ICMP_SGE:
result = (L >= R);
break;
case CmpInst::ICMP_SLT:
result = (L < R);
break;
case CmpInst::ICMP_SLE:
result = (L <= R);
break;
}
frame.AssignValue(inst, result, llvm_module);
if (log)
{
log->Printf("Interpreted an ICmpInst");
log->Printf(" L : %s", frame.SummarizeValue(lhs).c_str());
log->Printf(" R : %s", frame.SummarizeValue(rhs).c_str());
log->Printf(" = : %s", frame.SummarizeValue(inst).c_str());
}
}
break;
case Instruction::IntToPtr:
{
const IntToPtrInst *int_to_ptr_inst = dyn_cast<IntToPtrInst>(inst);
if (!int_to_ptr_inst)
{
if (log)
log->Printf("getOpcode() returns IntToPtr, but instruction is not an IntToPtrInst");
return false;
}
Value *src_operand = int_to_ptr_inst->getOperand(0);
lldb_private::Scalar I;
if (!frame.EvaluateValue(I, src_operand, llvm_module))
return false;
frame.AssignValue(inst, I, llvm_module);
if (log)
{
log->Printf("Interpreted an IntToPtr");
log->Printf(" Src : %s", frame.SummarizeValue(src_operand).c_str());
log->Printf(" = : %s", frame.SummarizeValue(inst).c_str());
}
}
break;
case Instruction::Load:
{
const LoadInst *load_inst = dyn_cast<LoadInst>(inst);
if (!load_inst)
{
if (log)
log->Printf("getOpcode() returns Load, but instruction is not a LoadInst");
return false;
}
// The semantics of Load are:
// Create a region D that will contain the loaded data
// Resolve the region P containing a pointer
// Dereference P to get the region R that the data should be loaded from
// Transfer a unit of type type(D) from R to D
const Value *pointer_operand = load_inst->getPointerOperand();
Type *pointer_ty = pointer_operand->getType();
PointerType *pointer_ptr_ty = dyn_cast<PointerType>(pointer_ty);
if (!pointer_ptr_ty)
return false;
Type *target_ty = pointer_ptr_ty->getElementType();
Memory::Region D = frame.ResolveValue(load_inst, llvm_module);
Memory::Region P = frame.ResolveValue(pointer_operand, llvm_module);
if (D.IsInvalid())
{
if (log)
log->Printf("LoadInst's value doesn't resolve to anything");
return false;
}
if (P.IsInvalid())
{
if (log)
log->Printf("LoadInst's pointer doesn't resolve to anything");
return false;
}
DataExtractorSP P_extractor(memory.GetExtractor(P));
DataEncoderSP D_encoder(memory.GetEncoder(D));
uint32_t offset = 0;
lldb::addr_t pointer = P_extractor->GetAddress(&offset);
Memory::Region R = memory.Lookup(pointer, target_ty);
if (R.IsValid())
{
if (!memory.Read(D_encoder->GetDataStart(), R.m_base, target_data.getTypeStoreSize(target_ty)))
{
if (log)
log->Printf("Couldn't read from a region on behalf of a LoadInst");
return false;
}
}
else
{
if (!memory.ReadFromRawPtr(D_encoder->GetDataStart(), pointer, target_data.getTypeStoreSize(target_ty)))
{
if (log)
log->Printf("Couldn't read from a raw pointer on behalf of a LoadInst");
return false;
}
}
if (log)
{
log->Printf("Interpreted a LoadInst");
log->Printf(" P : %s", frame.SummarizeValue(pointer_operand).c_str());
if (R.IsValid())
log->Printf(" R : %s", memory.SummarizeRegion(R).c_str());
else
log->Printf(" R : raw pointer 0x%llx", (unsigned long long)pointer);
log->Printf(" D : %s", frame.SummarizeValue(load_inst).c_str());
}
}
break;
case Instruction::Ret:
{
if (result_name.IsEmpty())
return true;
GlobalValue *result_value = llvm_module.getNamedValue(result_name.GetCString());
return frame.ConstructResult(result, result_value, result_name, result_type, llvm_module);
}
case Instruction::Store:
{
const StoreInst *store_inst = dyn_cast<StoreInst>(inst);
if (!store_inst)
{
if (log)
log->Printf("getOpcode() returns Store, but instruction is not a StoreInst");
return false;
}
// The semantics of Store are:
// Resolve the region D containing the data to be stored
// Resolve the region P containing a pointer
// Dereference P to get the region R that the data should be stored in
// Transfer a unit of type type(D) from D to R
const Value *value_operand = store_inst->getValueOperand();
const Value *pointer_operand = store_inst->getPointerOperand();
Type *pointer_ty = pointer_operand->getType();
PointerType *pointer_ptr_ty = dyn_cast<PointerType>(pointer_ty);
if (!pointer_ptr_ty)
return false;
Type *target_ty = pointer_ptr_ty->getElementType();
Memory::Region D = frame.ResolveValue(value_operand, llvm_module);
Memory::Region P = frame.ResolveValue(pointer_operand, llvm_module);
if (D.IsInvalid())
{
if (log)
log->Printf("StoreInst's value doesn't resolve to anything");
return false;
}
if (P.IsInvalid())
{
if (log)
log->Printf("StoreInst's pointer doesn't resolve to anything");
return false;
}
DataExtractorSP P_extractor(memory.GetExtractor(P));
DataExtractorSP D_extractor(memory.GetExtractor(D));
if (!P_extractor || !D_extractor)
return false;
uint32_t offset = 0;
lldb::addr_t pointer = P_extractor->GetAddress(&offset);
Memory::Region R = memory.Lookup(pointer, target_ty);
if (R.IsValid())
{
if (!memory.Write(R.m_base, D_extractor->GetDataStart(), target_data.getTypeStoreSize(target_ty)))
{
if (log)
log->Printf("Couldn't write to a region on behalf of a LoadInst");
return false;
}
}
else
{
if (!memory.WriteToRawPtr(pointer, D_extractor->GetDataStart(), target_data.getTypeStoreSize(target_ty)))
{
if (log)
log->Printf("Couldn't write to a raw pointer on behalf of a LoadInst");
return false;
}
}
if (log)
{
log->Printf("Interpreted a StoreInst");
log->Printf(" D : %s", frame.SummarizeValue(value_operand).c_str());
log->Printf(" P : %s", frame.SummarizeValue(pointer_operand).c_str());
log->Printf(" R : %s", memory.SummarizeRegion(R).c_str());
}
}
break;
}
++frame.m_ii;
}
if (num_insts >= 4096)
return false;
return false;
}