diff options
Diffstat (limited to 'source/Plugins/ExpressionParser/Go/GoUserExpression.cpp')
| -rw-r--r-- | source/Plugins/ExpressionParser/Go/GoUserExpression.cpp | 756 |
1 files changed, 756 insertions, 0 deletions
diff --git a/source/Plugins/ExpressionParser/Go/GoUserExpression.cpp b/source/Plugins/ExpressionParser/Go/GoUserExpression.cpp new file mode 100644 index 0000000..3f12a2b --- /dev/null +++ b/source/Plugins/ExpressionParser/Go/GoUserExpression.cpp @@ -0,0 +1,756 @@ +//===-- GoUserExpression.cpp ------------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +// C Includes +#include <stdio.h> +#if HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif + +// C++ Includes +#include <cstdlib> +#include <memory> +#include <string> +#include <vector> + +// Other libraries and framework includes +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/StringMap.h" + +// Project includes +#include "GoUserExpression.h" + +#include "lldb/lldb-private.h" +#include "lldb/Core/ConstString.h" +#include "lldb/Core/DataBufferHeap.h" +#include "lldb/Core/DataEncoder.h" +#include "lldb/Core/DataExtractor.h" +#include "lldb/Core/Log.h" +#include "lldb/Core/Module.h" +#include "lldb/Core/StreamFile.h" +#include "lldb/Core/StreamString.h" +#include "lldb/Core/ValueObjectConstResult.h" +#include "lldb/Core/ValueObjectRegister.h" +#include "lldb/Expression/ExpressionVariable.h" +#include "lldb/Symbol/TypeList.h" +#include "lldb/Symbol/GoASTContext.h" +#include "lldb/Symbol/VariableList.h" +#include "lldb/Target/ExecutionContext.h" +#include "lldb/Target/Process.h" +#include "lldb/Target/RegisterContext.h" +#include "lldb/Target/StackFrame.h" +#include "lldb/Target/Target.h" +#include "lldb/Target/ThreadPlan.h" +#include "lldb/Target/ThreadPlanCallUserExpression.h" + +#include "Plugins/ExpressionParser/Go/GoAST.h" +#include "Plugins/ExpressionParser/Go/GoParser.h" + +using namespace lldb_private; +using namespace lldb; + +class GoUserExpression::GoInterpreter +{ + public: + GoInterpreter(ExecutionContext &exe_ctx, const char *expr) + : m_exe_ctx(exe_ctx), m_frame(exe_ctx.GetFrameSP()), m_parser(expr) + { + if (m_frame) + { + const SymbolContext &ctx = m_frame->GetSymbolContext(eSymbolContextFunction); + ConstString fname = ctx.GetFunctionName(); + if (fname.GetLength() > 0) + { + size_t dot = fname.GetStringRef().find('.'); + if (dot != llvm::StringRef::npos) + m_package = llvm::StringRef(fname.AsCString(), dot); + } + } + } + + void + set_use_dynamic(DynamicValueType use_dynamic) + { + m_use_dynamic = use_dynamic; + } + + bool Parse(); + lldb::ValueObjectSP Evaluate(ExecutionContext &exe_ctx); + lldb::ValueObjectSP EvaluateStatement(const GoASTStmt *s); + lldb::ValueObjectSP EvaluateExpr(const GoASTExpr *e); + + ValueObjectSP + VisitBadExpr(const GoASTBadExpr *e) + { + m_parser.GetError(m_error); + return nullptr; + } + + ValueObjectSP VisitParenExpr(const GoASTParenExpr *e); + ValueObjectSP VisitIdent(const GoASTIdent *e); + ValueObjectSP VisitStarExpr(const GoASTStarExpr *e); + ValueObjectSP VisitSelectorExpr(const GoASTSelectorExpr *e); + ValueObjectSP VisitBasicLit(const GoASTBasicLit *e); + ValueObjectSP VisitIndexExpr(const GoASTIndexExpr *e); + ValueObjectSP VisitUnaryExpr(const GoASTUnaryExpr *e); + ValueObjectSP VisitCallExpr(const GoASTCallExpr *e); + + ValueObjectSP + VisitTypeAssertExpr(const GoASTTypeAssertExpr *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitBinaryExpr(const GoASTBinaryExpr *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitArrayType(const GoASTArrayType *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitChanType(const GoASTChanType *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitCompositeLit(const GoASTCompositeLit *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitEllipsis(const GoASTEllipsis *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitFuncType(const GoASTFuncType *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitFuncLit(const GoASTFuncLit *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitInterfaceType(const GoASTInterfaceType *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitKeyValueExpr(const GoASTKeyValueExpr *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitMapType(const GoASTMapType *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitSliceExpr(const GoASTSliceExpr *e) + { + return NotImplemented(e); + } + + ValueObjectSP + VisitStructType(const GoASTStructType *e) + { + return NotImplemented(e); + } + + CompilerType EvaluateType(const GoASTExpr *e); + + Error & + error() + { + return m_error; + } + + private: + std::nullptr_t + NotImplemented(const GoASTExpr *e) + { + m_error.SetErrorStringWithFormat("%s node not implemented", e->GetKindName()); + return nullptr; + } + + ExecutionContext m_exe_ctx; + lldb::StackFrameSP m_frame; + GoParser m_parser; + DynamicValueType m_use_dynamic; + Error m_error; + llvm::StringRef m_package; + std::vector<std::unique_ptr<GoASTStmt>> m_statements; +}; + +VariableSP +FindGlobalVariable(TargetSP target, llvm::Twine name) +{ + ConstString fullname(name.str()); + VariableList variable_list; + const bool append = true; + if (!target) + { + return nullptr; + } + const uint32_t match_count = target->GetImages().FindGlobalVariables(fullname, append, 1, variable_list); + if (match_count == 1) + { + return variable_list.GetVariableAtIndex(0); + } + return nullptr; +} + +CompilerType +LookupType(TargetSP target, ConstString name) +{ + if (!target) + return CompilerType(); + SymbolContext sc; + TypeList type_list; + uint32_t num_matches = target->GetImages().FindTypes(sc, name, false, 2, type_list); + if (num_matches > 0) + { + return type_list.GetTypeAtIndex(0)->GetFullCompilerType(); + } + return CompilerType(); +} + +GoUserExpression::GoUserExpression(ExecutionContextScope &exe_scope, const char *expr, const char *expr_prefix, + lldb::LanguageType language, ResultType desired_type, + const EvaluateExpressionOptions &options) + : UserExpression(exe_scope, expr, expr_prefix, language, desired_type, options) +{ +} + +bool +GoUserExpression::Parse(Stream &error_stream, ExecutionContext &exe_ctx, lldb_private::ExecutionPolicy execution_policy, + bool keep_result_in_memory, bool generate_debug_info) +{ + InstallContext(exe_ctx); + m_interpreter.reset(new GoInterpreter(exe_ctx, GetUserText())); + if (m_interpreter->Parse()) + return true; + const char *error_cstr = m_interpreter->error().AsCString(); + if (error_cstr && error_cstr[0]) + error_stream.Printf("error: %s\n", error_cstr); + else + error_stream.Printf("error: expression can't be interpreted or run\n"); + return false; +} + +lldb::ExpressionResults +GoUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, const EvaluateExpressionOptions &options, + lldb::UserExpressionSP &shared_ptr_to_me, lldb::ExpressionVariableSP &result) +{ + Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP)); + + lldb_private::ExecutionPolicy execution_policy = options.GetExecutionPolicy(); + lldb::ExpressionResults execution_results = lldb::eExpressionSetupError; + + Process *process = exe_ctx.GetProcessPtr(); + Target *target = exe_ctx.GetTargetPtr(); + + if (target == nullptr || process == nullptr || process->GetState() != lldb::eStateStopped) + { + if (execution_policy == eExecutionPolicyAlways) + { + if (log) + log->Printf("== [GoUserExpression::Evaluate] Expression may not run, but is not constant =="); + + error_stream.Printf("expression needed to run but couldn't"); + + return execution_results; + } + } + + m_interpreter->set_use_dynamic(options.GetUseDynamic()); + ValueObjectSP result_val_sp = m_interpreter->Evaluate(exe_ctx); + Error err = m_interpreter->error(); + m_interpreter.reset(); + + if (!result_val_sp) + { + const char *error_cstr = err.AsCString(); + if (error_cstr && error_cstr[0]) + error_stream.Printf("error: %s\n", error_cstr); + else + error_stream.Printf("error: expression can't be interpreted or run\n"); + return lldb::eExpressionDiscarded; + } + result.reset(new ExpressionVariable(ExpressionVariable::eKindGo)); + result->m_live_sp = result->m_frozen_sp = result_val_sp; + result->m_flags |= ExpressionVariable::EVIsProgramReference; + PersistentExpressionState *pv = target->GetPersistentExpressionStateForLanguage(eLanguageTypeGo); + if (pv != nullptr) + { + result->SetName(pv->GetNextPersistentVariableName()); + pv->AddVariable(result); + } + return lldb::eExpressionCompleted; +} + +bool +GoUserExpression::GoInterpreter::Parse() +{ + for (std::unique_ptr<GoASTStmt> stmt(m_parser.Statement()); stmt; stmt.reset(m_parser.Statement())) + { + if (m_parser.Failed()) + break; + m_statements.emplace_back(std::move(stmt)); + } + if (m_parser.Failed() || !m_parser.AtEOF()) + m_parser.GetError(m_error); + + return m_error.Success(); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::Evaluate(ExecutionContext &exe_ctx) +{ + m_exe_ctx = exe_ctx; + ValueObjectSP result; + for (const std::unique_ptr<GoASTStmt> &stmt : m_statements) + { + result = EvaluateStatement(stmt.get()); + if (m_error.Fail()) + return nullptr; + } + return result; +} + +ValueObjectSP +GoUserExpression::GoInterpreter::EvaluateStatement(const lldb_private::GoASTStmt *stmt) +{ + ValueObjectSP result; + switch (stmt->GetKind()) + { + case GoASTNode::eBlockStmt: + { + const GoASTBlockStmt *block = llvm::cast<GoASTBlockStmt>(stmt); + for (size_t i = 0; i < block->NumList(); ++i) + result = EvaluateStatement(block->GetList(i)); + break; + } + case GoASTNode::eBadStmt: + m_parser.GetError(m_error); + break; + case GoASTNode::eExprStmt: + { + const GoASTExprStmt *expr = llvm::cast<GoASTExprStmt>(stmt); + return EvaluateExpr(expr->GetX()); + } + default: + m_error.SetErrorStringWithFormat("%s node not supported", stmt->GetKindName()); + } + return result; +} + +ValueObjectSP +GoUserExpression::GoInterpreter::EvaluateExpr(const lldb_private::GoASTExpr *e) +{ + if (e) + return e->Visit<ValueObjectSP>(this); + return ValueObjectSP(); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitParenExpr(const lldb_private::GoASTParenExpr *e) +{ + return EvaluateExpr(e->GetX()); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitIdent(const GoASTIdent *e) +{ + ValueObjectSP val; + if (m_frame) + { + VariableSP var_sp; + std::string varname = e->GetName().m_value.str(); + if (varname.size() > 1 && varname[0] == '$') + { + RegisterContextSP reg_ctx_sp = m_frame->GetRegisterContext(); + const RegisterInfo *reg = reg_ctx_sp->GetRegisterInfoByName(varname.c_str() + 1); + if (reg) + { + std::string type; + switch (reg->encoding) + { + case lldb::eEncodingSint: + type.append("int"); + break; + case lldb::eEncodingUint: + type.append("uint"); + break; + case lldb::eEncodingIEEE754: + type.append("float"); + break; + default: + m_error.SetErrorString("Invaild register encoding"); + return nullptr; + } + switch (reg->byte_size) + { + case 8: + type.append("64"); + break; + case 4: + type.append("32"); + break; + case 2: + type.append("16"); + break; + case 1: + type.append("8"); + break; + default: + m_error.SetErrorString("Invaild register size"); + return nullptr; + } + ValueObjectSP regVal = + ValueObjectRegister::Create(m_frame.get(), reg_ctx_sp, reg->kinds[eRegisterKindLLDB]); + CompilerType goType = LookupType(m_frame->CalculateTarget(), ConstString(type)); + if (regVal) + { + regVal = regVal->Cast(goType); + return regVal; + } + } + m_error.SetErrorString("Invaild register name"); + return nullptr; + } + VariableListSP var_list_sp(m_frame->GetInScopeVariableList(false)); + if (var_list_sp) + { + var_sp = var_list_sp->FindVariable(ConstString(varname)); + if (var_sp) + val = m_frame->GetValueObjectForFrameVariable(var_sp, m_use_dynamic); + else + { + // When a variable is on the heap instead of the stack, go records a variable + // '&x' instead of 'x'. + var_sp = var_list_sp->FindVariable(ConstString("&" + varname)); + if (var_sp) + { + val = m_frame->GetValueObjectForFrameVariable(var_sp, m_use_dynamic); + if (val) + val = val->Dereference(m_error); + if (m_error.Fail()) + return nullptr; + } + } + } + if (!val) + { + m_error.Clear(); + TargetSP target = m_frame->CalculateTarget(); + if (!target) + { + m_error.SetErrorString("No target"); + return nullptr; + } + var_sp = FindGlobalVariable(target, m_package + "." + e->GetName().m_value); + if (var_sp) + return m_frame->TrackGlobalVariable(var_sp, m_use_dynamic); + } + } + if (!val) + m_error.SetErrorStringWithFormat("Unknown variable %s", e->GetName().m_value.str().c_str()); + return val; +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitStarExpr(const GoASTStarExpr *e) +{ + ValueObjectSP target = EvaluateExpr(e->GetX()); + if (!target) + return nullptr; + return target->Dereference(m_error); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitSelectorExpr(const lldb_private::GoASTSelectorExpr *e) +{ + ValueObjectSP target = EvaluateExpr(e->GetX()); + if (target) + { + if (target->GetCompilerType().IsPointerType()) + { + target = target->Dereference(m_error); + if (m_error.Fail()) + return nullptr; + } + ConstString field(e->GetSel()->GetName().m_value); + ValueObjectSP result = target->GetChildMemberWithName(field, true); + if (!result) + m_error.SetErrorStringWithFormat("Unknown child %s", field.AsCString()); + return result; + } + if (const GoASTIdent *package = llvm::dyn_cast<GoASTIdent>(e->GetX())) + { + if (VariableSP global = FindGlobalVariable(m_exe_ctx.GetTargetSP(), + package->GetName().m_value + "." + e->GetSel()->GetName().m_value)) + { + if (m_frame) + { + m_error.Clear(); + return m_frame->GetValueObjectForFrameVariable(global, m_use_dynamic); + } + } + } + if (const GoASTBasicLit *packageLit = llvm::dyn_cast<GoASTBasicLit>(e->GetX())) + { + if (packageLit->GetValue().m_type == GoLexer::LIT_STRING) + { + std::string value = packageLit->GetValue().m_value.str(); + value = value.substr(1, value.size() - 2); + if (VariableSP global = + FindGlobalVariable(m_exe_ctx.GetTargetSP(), value + "." + e->GetSel()->GetName().m_value)) + { + if (m_frame) + { + m_error.Clear(); + return m_frame->TrackGlobalVariable(global, m_use_dynamic); + } + } + } + } + // EvaluateExpr should have already set m_error. + return target; +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitBasicLit(const lldb_private::GoASTBasicLit *e) +{ + std::string value = e->GetValue().m_value.str(); + if (e->GetValue().m_type != GoLexer::LIT_INTEGER) + { + m_error.SetErrorStringWithFormat("Unsupported literal %s", value.c_str()); + return nullptr; + } + errno = 0; + int64_t intvalue = strtol(value.c_str(), nullptr, 0); + if (errno != 0) + { + m_error.SetErrorToErrno(); + return nullptr; + } + DataBufferSP buf(new DataBufferHeap(sizeof(intvalue), 0)); + TargetSP target = m_exe_ctx.GetTargetSP(); + if (!target) + { + m_error.SetErrorString("No target"); + return nullptr; + } + ByteOrder order = target->GetArchitecture().GetByteOrder(); + uint8_t addr_size = target->GetArchitecture().GetAddressByteSize(); + DataEncoder enc(buf, order, addr_size); + enc.PutU64(0, static_cast<uint64_t>(intvalue)); + DataExtractor data(buf, order, addr_size); + + CompilerType type = LookupType(target, ConstString("int64")); + return ValueObject::CreateValueObjectFromData(nullptr, data, m_exe_ctx, type); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitIndexExpr(const lldb_private::GoASTIndexExpr *e) +{ + ValueObjectSP target = EvaluateExpr(e->GetX()); + if (!target) + return nullptr; + ValueObjectSP index = EvaluateExpr(e->GetIndex()); + if (!index) + return nullptr; + bool is_signed; + if (!index->GetCompilerType().IsIntegerType(is_signed)) + { + m_error.SetErrorString("Unsupported index"); + return nullptr; + } + size_t idx; + if (is_signed) + idx = index->GetValueAsSigned(0); + else + idx = index->GetValueAsUnsigned(0); + if (GoASTContext::IsGoSlice(target->GetCompilerType())) + { + target = target->GetStaticValue(); + ValueObjectSP cap = target->GetChildMemberWithName(ConstString("cap"), true); + if (cap) + { + uint64_t capval = cap->GetValueAsUnsigned(0); + if (idx >= capval) + { + m_error.SetErrorStringWithFormat("Invalid index %" PRIu64 " , cap = %" PRIu64, uint64_t(idx), capval); + return nullptr; + } + } + target = target->GetChildMemberWithName(ConstString("array"), true); + if (target && m_use_dynamic != eNoDynamicValues) + { + ValueObjectSP dynamic = target->GetDynamicValue(m_use_dynamic); + if (dynamic) + target = dynamic; + } + if (!target) + return nullptr; + return target->GetSyntheticArrayMember(idx, true); + } + return target->GetChildAtIndex(idx, true); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitUnaryExpr(const GoASTUnaryExpr *e) +{ + ValueObjectSP x = EvaluateExpr(e->GetX()); + if (!x) + return nullptr; + switch (e->GetOp()) + { + case GoLexer::OP_AMP: + { + CompilerType type = x->GetCompilerType().GetPointerType(); + uint64_t address = x->GetAddressOf(); + return ValueObject::CreateValueObjectFromAddress(nullptr, address, m_exe_ctx, type); + } + case GoLexer::OP_PLUS: + return x; + default: + m_error.SetErrorStringWithFormat("Operator %s not supported", + GoLexer::LookupToken(e->GetOp()).str().c_str()); + return nullptr; + } +} + +CompilerType +GoUserExpression::GoInterpreter::EvaluateType(const GoASTExpr *e) +{ + TargetSP target = m_exe_ctx.GetTargetSP(); + if (auto *id = llvm::dyn_cast<GoASTIdent>(e)) + { + CompilerType result = LookupType(target, ConstString(id->GetName().m_value)); + if (result.IsValid()) + return result; + std::string fullname = (m_package + "." + id->GetName().m_value).str(); + result = LookupType(target, ConstString(fullname)); + if (!result) + m_error.SetErrorStringWithFormat("Unknown type %s", fullname.c_str()); + return result; + } + if (auto *sel = llvm::dyn_cast<GoASTSelectorExpr>(e)) + { + std::string package; + if (auto *pkg_node = llvm::dyn_cast<GoASTIdent>(sel->GetX())) + { + package = pkg_node->GetName().m_value.str(); + } + else if (auto *str_node = llvm::dyn_cast<GoASTBasicLit>(sel->GetX())) + { + if (str_node->GetValue().m_type == GoLexer::LIT_STRING) + { + package = str_node->GetValue().m_value.substr(1).str(); + package.resize(package.length() - 1); + } + } + if (package.empty()) + { + m_error.SetErrorStringWithFormat("Invalid %s in type expression", sel->GetX()->GetKindName()); + return CompilerType(); + } + std::string fullname = (package + "." + sel->GetSel()->GetName().m_value).str(); + CompilerType result = LookupType(target, ConstString(fullname)); + if (!result) + m_error.SetErrorStringWithFormat("Unknown type %s", fullname.c_str()); + return result; + } + if (auto *star = llvm::dyn_cast<GoASTStarExpr>(e)) + { + CompilerType elem = EvaluateType(star->GetX()); + return elem.GetPointerType(); + } + if (auto *paren = llvm::dyn_cast<GoASTParenExpr>(e)) + return EvaluateType(paren->GetX()); + if (auto *array = llvm::dyn_cast<GoASTArrayType>(e)) + { + CompilerType elem = EvaluateType(array->GetElt()); + } + + m_error.SetErrorStringWithFormat("Invalid %s in type expression", e->GetKindName()); + return CompilerType(); +} + +ValueObjectSP +GoUserExpression::GoInterpreter::VisitCallExpr(const lldb_private::GoASTCallExpr *e) +{ + ValueObjectSP x = EvaluateExpr(e->GetFun()); + if (x || e->NumArgs() != 1) + { + m_error.SetErrorStringWithFormat("Code execution not supported"); + return nullptr; + } + m_error.Clear(); + CompilerType type = EvaluateType(e->GetFun()); + if (!type) + { + return nullptr; + } + ValueObjectSP value = EvaluateExpr(e->GetArgs(0)); + if (!value) + return nullptr; + // TODO: Handle special conversions + return value->Cast(type); +} + +GoPersistentExpressionState::GoPersistentExpressionState() : PersistentExpressionState(eKindGo) +{ +} + +ConstString +GoPersistentExpressionState::GetNextPersistentVariableName() +{ + char name_cstr[256]; + // We can't use the same variable format as clang. + ::snprintf(name_cstr, sizeof(name_cstr), "$go%u", m_next_persistent_variable_id++); + ConstString name(name_cstr); + return name; +} + +void +GoPersistentExpressionState::RemovePersistentVariable(lldb::ExpressionVariableSP variable) +{ + RemoveVariable(variable); + + const char *name = variable->GetName().AsCString(); + + if (*(name++) != '$') + return; + if (*(name++) != 'g') + return; + if (*(name++) != 'o') + return; + + if (strtoul(name, nullptr, 0) == m_next_persistent_variable_id - 1) + m_next_persistent_variable_id--; +} |
