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lldb-wasm.patch
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diff --git a/lldb/include/lldb/Breakpoint/Breakpoint.h b/lldb/include/lldb/Breakpoint/Breakpoint.h
index f2e2a0d22..426d1129b 100644
--- a/lldb/include/lldb/Breakpoint/Breakpoint.h
+++ b/lldb/include/lldb/Breakpoint/Breakpoint.h
@@ -9,6 +9,7 @@
#ifndef LLDB_BREAKPOINT_BREAKPOINT_H
#define LLDB_BREAKPOINT_BREAKPOINT_H
+#include <limits>
#include <memory>
#include <string>
#include <unordered_set>
diff --git a/lldb/include/lldb/Core/Module.h b/lldb/include/lldb/Core/Module.h
index dd7100c46..97d70daad 100644
--- a/lldb/include/lldb/Core/Module.h
+++ b/lldb/include/lldb/Core/Module.h
@@ -41,6 +41,7 @@
namespace lldb_private {
class CompilerDeclContext;
+class DWARFEvaluatorFactory;
class Function;
class Log;
class ObjectFile;
@@ -859,6 +860,8 @@ public:
/// Update the ArchSpec to a more specific variant.
bool MergeArchitecture(const ArchSpec &arch_spec);
+ DWARFEvaluatorFactory *GetDWARFExpressionEvaluatorFactory();
+
/// \class LookupInfo Module.h "lldb/Core/Module.h"
/// A class that encapsulates name lookup information.
///
@@ -985,6 +988,8 @@ protected:
m_first_file_changed_log : 1; /// See if the module was modified after it
/// was initially opened.
+ std::unique_ptr<DWARFEvaluatorFactory> m_dwarf_evaluator_factory;
+
/// Resolve a file or load virtual address.
///
/// Tries to resolve \a vm_addr as a file address (if \a
diff --git a/lldb/include/lldb/Core/PluginManager.h b/lldb/include/lldb/Core/PluginManager.h
index be91929c6..8d876fc1f 100644
--- a/lldb/include/lldb/Core/PluginManager.h
+++ b/lldb/include/lldb/Core/PluginManager.h
@@ -508,6 +508,17 @@ public:
static bool CreateSettingForStructuredDataPlugin(
Debugger &debugger, const lldb::OptionValuePropertiesSP &properties_sp,
ConstString description, bool is_global_property);
+
+ // DWARFEvaluatorFactory
+ static bool
+ RegisterPlugin(ConstString name, const char *description,
+ DWARFEvaluatorFactoryCreateInstance create_callback);
+
+ static bool
+ UnregisterPlugin(DWARFEvaluatorFactoryCreateInstance create_callback);
+
+ static DWARFEvaluatorFactoryCreateInstance
+ GetDWARFEvaluatorFactoryCreateCallbackAtIndex(uint32_t idx);
};
} // namespace lldb_private
diff --git a/lldb/include/lldb/Expression/DWARFEvaluator.h b/lldb/include/lldb/Expression/DWARFEvaluator.h
new file mode 100644
index 000000000..6811cbeae
--- /dev/null
+++ b/lldb/include/lldb/Expression/DWARFEvaluator.h
@@ -0,0 +1,110 @@
+//===-- DWARFEvaluator.h ----------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_EXPRESSION_DWARFEVALUATOR_H
+#define LLDB_EXPRESSION_DWARFEVALUATOR_H
+
+#include "lldb/lldb-private.h"
+#include <vector>
+
+namespace lldb_private {
+
+class DWARFExpression;
+
+/// \class DWARFEvaluator DWARFEvaluator.h
+/// "lldb/Expression/DWARFEvaluator.h" Evaluates DWARF opcodes.
+///
+class DWARFEvaluator {
+public:
+ /// Crates a DWARF location expression evaluator
+ ///
+ /// \param[in] dwarf_expression
+ /// The DWARF expression to evaluate.
+ ///
+ /// \param[in] exe_ctx
+ /// The execution context in which to evaluate the location
+ /// expression. The location expression may access the target's
+ /// memory, especially if it comes from the expression parser.
+ ///
+ /// \param[in] reg_ctx
+ /// An optional parameter which provides a RegisterContext for use
+ /// when evaluating the expression (i.e. for fetching register values).
+ /// Normally this will come from the ExecutionContext's StackFrame but
+ /// in the case where an expression needs to be evaluated while building
+ /// the stack frame list, this short-cut is available.
+ ///
+ /// \param[in] initial_value_ptr
+ /// A value to put on top of the interpreter stack before evaluating
+ /// the expression, if the expression is parametrized. Can be NULL.
+ ///
+ /// \param[in] object_address_ptr
+ ///
+ DWARFEvaluator(const DWARFExpression &dwarf_expression,
+ ExecutionContext *exe_ctx, RegisterContext *reg_ctx,
+ const Value *initial_value_ptr,
+ const Value *object_address_ptr);
+
+ /// DWARFEvaluator protocol.
+ /// \{
+
+ /// Evaluate the DWARF location expression
+ ///
+ /// \param[in] result
+ /// A value into which the result of evaluating the expression is
+ /// to be placed.
+ ///
+ /// \param[in] error_ptr
+ /// If non-NULL, used to report errors in expression evaluation.
+ ///
+ /// \return
+ /// True on success; false otherwise. If error_ptr is non-NULL,
+ /// details of the failure are provided through it.
+ virtual bool Evaluate(Value &result, Status *error_ptr);
+
+ /// Evaluate the DWARF location expression with the opcodes specified.
+ ///
+ /// \param[in] opcodes
+ /// The DWARF opcodes to evaluate.
+ ///
+ /// \param[in] result
+ /// A value into which the result of evaluating the expression is
+ /// to be placed.
+ ///
+ /// \param[in] error_ptr
+ /// If non-NULL, used to report errors in expression evaluation.
+ ///
+ /// \return
+ /// True on success; false otherwise. If error_ptr is non-NULL,
+ /// details of the failure are provided through it.
+ virtual bool Evaluate(const DataExtractor &opcodes, Value &result,
+ Status *error_ptr);
+
+ /// Evaluates a specific DWARF opcode in the context of a DWARF expression
+ virtual bool Evaluate(const uint8_t op, Process *process, StackFrame *frame,
+ std::vector<Value> &stack, const DataExtractor &opcodes,
+ lldb::offset_t &offset, Value &pieces,
+ uint64_t &op_piece_offset, Log *log, Status *error_ptr);
+
+ /// \}
+
+protected:
+ const DWARFExpression &m_dwarf_expression;
+ ExecutionContext *m_exe_ctx;
+ RegisterContext *m_reg_ctx;
+ const Value *m_initial_value_ptr;
+ const Value *m_object_address_ptr;
+
+private:
+ DWARFEvaluator(const DWARFEvaluator &);
+ const DWARFEvaluator &operator=(const DWARFEvaluator &) = delete;
+
+};
+
+} // namespace lldb_private
+
+#endif // LLDB_EXPRESSION_DWARFEVALUATOR_H
diff --git a/lldb/include/lldb/Expression/DWARFEvaluatorFactory.h b/lldb/include/lldb/Expression/DWARFEvaluatorFactory.h
new file mode 100644
index 000000000..f3b496c58
--- /dev/null
+++ b/lldb/include/lldb/Expression/DWARFEvaluatorFactory.h
@@ -0,0 +1,56 @@
+//===-- DWARFEvaluatorFactory.h ---------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_EXPRESSION_DWARFEVALUATORFACTORY_H
+#define LLDB_EXPRESSION_DWARFEVALUATORFACTORY_H
+
+#include "lldb/Core/PluginInterface.h"
+#include "lldb/Utility/ConstString.h"
+#include "lldb/lldb-private.h"
+
+class DWARFUnit;
+
+namespace lldb_private {
+
+class DWARFEvaluator;
+class DWARFExpression;
+
+/// \class DWARFEvaluatorFactory DWARFEvaluatorFactory.h
+/// "lldb/Expression/DWARFEvaluatorFactory.h" Factory class that allows the
+/// registration of platform-specific DWARF expression evaluators, used to
+/// handle platform-specific DWARF opcodes.
+class DWARFEvaluatorFactory : public PluginInterface {
+public:
+ static std::unique_ptr<DWARFEvaluatorFactory> FindPlugin(Module *module);
+
+ /// PluginInterface protocol.
+ /// \{
+ ConstString GetPluginName() override;
+
+ uint32_t GetPluginVersion() override { return 1; }
+ /// \}
+
+ DWARFEvaluatorFactory() {}
+
+ /// DWARFEvaluatorFactory protocol.
+ /// \{
+ virtual std::unique_ptr<DWARFEvaluator>
+ CreateDWARFEvaluator(const DWARFExpression &dwarf_expression,
+ ExecutionContext *exe_ctx, RegisterContext *reg_ctx,
+ const Value *initial_value_ptr,
+ const Value *object_address_ptr);
+ /// \}
+
+private:
+ DWARFEvaluatorFactory(const DWARFEvaluatorFactory &);
+ const DWARFEvaluatorFactory &operator=(const DWARFEvaluatorFactory &) = delete;
+};
+
+} // namespace lldb_private
+
+#endif // LLDB_EXPRESSION_DWARFEVALUATORFACTORY_H
diff --git a/lldb/include/lldb/Expression/DWARFExpression.h b/lldb/include/lldb/Expression/DWARFExpression.h
index 1490ac2d6..35c741d4e 100644
--- a/lldb/include/lldb/Expression/DWARFExpression.h
+++ b/lldb/include/lldb/Expression/DWARFExpression.h
@@ -120,6 +120,10 @@ public:
void SetModule(const lldb::ModuleSP &module) { m_module_wp = module; }
+ lldb::ModuleSP GetModule() const { return m_module_wp.lock(); }
+
+ const DWARFUnit *GetDWARFCompileUnit() const { return m_dwarf_cu; }
+
bool ContainsThreadLocalStorage() const;
bool LinkThreadLocalStorage(
@@ -140,7 +144,7 @@ public:
lldb::addr_t func_file_addr);
/// Return the call-frame-info style register kind
- int GetRegisterKind();
+ lldb::RegisterKind GetRegisterKind() const;
/// Set the call-frame-info style register kind
///
@@ -219,6 +223,9 @@ public:
bool MatchesOperand(StackFrame &frame, const Instruction::Operand &op);
+ static lldb::addr_t ReadAddressFromDebugAddrSection(const DWARFUnit *dwarf_cu,
+ uint32_t index);
+
llvm::Optional<DataExtractor>
GetLocationExpression(lldb::addr_t load_function_start,
lldb::addr_t addr) const;
diff --git a/lldb/include/lldb/Target/Process.h b/lldb/include/lldb/Target/Process.h
index aaa2470d2..c15f2db52 100644
--- a/lldb/include/lldb/Target/Process.h
+++ b/lldb/include/lldb/Target/Process.h
@@ -1434,7 +1434,7 @@ public:
/// vm_addr, \a buf, and \a size updated appropriately. Zero is
/// returned in the case of an error.
virtual size_t ReadMemory(lldb::addr_t vm_addr, void *buf, size_t size,
- Status &error);
+ Status &error, ExecutionContext *exe_ctx = nullptr);
/// Read of memory from a process.
///
diff --git a/lldb/include/lldb/Target/ProcessTrace.h b/lldb/include/lldb/Target/ProcessTrace.h
index 7b9d6b13d..9525fc975 100644
--- a/lldb/include/lldb/Target/ProcessTrace.h
+++ b/lldb/include/lldb/Target/ProcessTrace.h
@@ -59,7 +59,7 @@ public:
bool WarnBeforeDetach() const override { return false; }
size_t ReadMemory(lldb::addr_t addr, void *buf, size_t size,
- Status &error) override;
+ Status &error, ExecutionContext *exe_ctx = nullptr) override;
size_t DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
Status &error) override;
diff --git a/lldb/include/lldb/lldb-forward.h b/lldb/include/lldb/lldb-forward.h
index ad5298151..5a3c0b27a 100644
--- a/lldb/include/lldb/lldb-forward.h
+++ b/lldb/include/lldb/lldb-forward.h
@@ -74,6 +74,7 @@ class Disassembler;
class DumpValueObjectOptions;
class DynamicCheckerFunctions;
class DynamicLoader;
+class DWARFEvaluatorFactory;
class Editline;
class EmulateInstruction;
class Environment;
diff --git a/lldb/include/lldb/lldb-private-interfaces.h b/lldb/include/lldb/lldb-private-interfaces.h
index 2ed083ec8..f4d500d19 100644
--- a/lldb/include/lldb/lldb-private-interfaces.h
+++ b/lldb/include/lldb/lldb-private-interfaces.h
@@ -113,6 +113,8 @@ typedef lldb::REPLSP (*REPLCreateInstance)(Status &error,
const char *repl_options);
typedef int (*ComparisonFunction)(const void *, const void *);
typedef void (*DebuggerInitializeCallback)(Debugger &debugger);
+typedef DWARFEvaluatorFactory *(*DWARFEvaluatorFactoryCreateInstance)(
+ Module *module);
/// Trace
/// \{
typedef llvm::Expected<lldb::TraceSP> (*TraceCreateInstanceForSessionFile)(
diff --git a/lldb/source/Core/Module.cpp b/lldb/source/Core/Module.cpp
index 19c97be15..1647f93ec 100644
--- a/lldb/source/Core/Module.cpp
+++ b/lldb/source/Core/Module.cpp
@@ -16,6 +16,7 @@
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/SearchFilter.h"
#include "lldb/Core/Section.h"
+#include "lldb/Expression/DWARFEvaluatorFactory.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/HostInfo.h"
@@ -1659,3 +1660,9 @@ bool Module::GetIsDynamicLinkEditor() {
return false;
}
+
+DWARFEvaluatorFactory *Module::GetDWARFExpressionEvaluatorFactory() {
+ if (!m_dwarf_evaluator_factory)
+ m_dwarf_evaluator_factory = DWARFEvaluatorFactory::FindPlugin(this);
+ return m_dwarf_evaluator_factory.get();
+}
diff --git a/lldb/source/Core/PluginManager.cpp b/lldb/source/Core/PluginManager.cpp
index fcaa868b0..59a404d4a 100644
--- a/lldb/source/Core/PluginManager.cpp
+++ b/lldb/source/Core/PluginManager.cpp
@@ -1597,3 +1597,32 @@ bool PluginManager::CreateSettingForStructuredDataPlugin(
ConstString("Settings for structured data plug-ins"), properties_sp,
description, is_global_property);
}
+
+#pragma mark DWARFEvaluator
+
+typedef PluginInstance<DWARFEvaluatorFactoryCreateInstance>
+ DWARFEvaluatorFactoryInstance;
+typedef PluginInstances<DWARFEvaluatorFactoryInstance>
+ DWARFEvaluatorFactoryInstances;
+
+static DWARFEvaluatorFactoryInstances &GetDWARFEvaluatorFactoryInstances() {
+ static DWARFEvaluatorFactoryInstances g_instances;
+ return g_instances;
+}
+
+bool PluginManager::RegisterPlugin(
+ ConstString name, const char *description,
+ DWARFEvaluatorFactoryCreateInstance create_callback) {
+ return GetDWARFEvaluatorFactoryInstances().RegisterPlugin(name, description,
+ create_callback);
+}
+
+bool PluginManager::UnregisterPlugin(
+ DWARFEvaluatorFactoryCreateInstance create_callback) {
+ return GetDWARFEvaluatorFactoryInstances().UnregisterPlugin(create_callback);
+}
+
+DWARFEvaluatorFactoryCreateInstance
+PluginManager::GetDWARFEvaluatorFactoryCreateCallbackAtIndex(uint32_t idx) {
+ return GetDWARFEvaluatorFactoryInstances().GetCallbackAtIndex(idx);
+}
diff --git a/lldb/source/Core/Value.cpp b/lldb/source/Core/Value.cpp
index fb57c0fed..f92d6a54d 100644
--- a/lldb/source/Core/Value.cpp
+++ b/lldb/source/Core/Value.cpp
@@ -538,7 +538,7 @@ Status Value::GetValueAsData(ExecutionContext *exe_ctx, DataExtractor &data,
if (process) {
const size_t bytes_read =
- process->ReadMemory(address, dst, byte_size, error);
+ process->ReadMemory(address, dst, byte_size, error, exe_ctx);
if (bytes_read != byte_size)
error.SetErrorStringWithFormat(
"read memory from 0x%" PRIx64 " failed (%u of %u bytes read)",
diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index 9c1ba99da..b15b214b2 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -735,7 +735,7 @@ size_t ValueObject::GetPointeeData(DataExtractor &data, uint32_t item_idx,
if (process) {
heap_buf_ptr->SetByteSize(bytes);
size_t bytes_read = process->ReadMemory(
- addr + offset, heap_buf_ptr->GetBytes(), bytes, error);
+ addr + offset, heap_buf_ptr->GetBytes(), bytes, error, &exe_ctx);
if (error.Success() || bytes_read > 0) {
data.SetData(data_sp);
return bytes_read;
diff --git a/lldb/source/Expression/CMakeLists.txt b/lldb/source/Expression/CMakeLists.txt
index bf94361dd..4e76d547a 100644
--- a/lldb/source/Expression/CMakeLists.txt
+++ b/lldb/source/Expression/CMakeLists.txt
@@ -1,5 +1,7 @@
add_lldb_library(lldbExpression
DiagnosticManager.cpp
+ DWARFEvaluator.cpp
+ DWARFEvaluatorFactory.cpp
DWARFExpression.cpp
Expression.cpp
ExpressionVariable.cpp
diff --git a/lldb/source/Expression/DWARFEvaluator.cpp b/lldb/source/Expression/DWARFEvaluator.cpp
new file mode 100644
index 000000000..06107e136
--- /dev/null
+++ b/lldb/source/Expression/DWARFEvaluator.cpp
@@ -0,0 +1,1952 @@
+//===-- DWARFEvaluator.cpp ------------ -----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Expression/DWARFEvaluator.h"
+#include "lldb/Expression/DWARFExpression.h"
+
+#include "lldb/Core/Module.h"
+#include "lldb/Core/Value.h"
+#include "lldb/Core/dwarf.h"
+
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/RegisterValue.h"
+
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StackFrame.h"
+
+#include "Plugins/SymbolFile/DWARF/DWARFUnit.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+DWARFEvaluator::DWARFEvaluator(const DWARFExpression &dwarf_expression,
+ ExecutionContext *exe_ctx,
+ RegisterContext *reg_ctx,
+ const Value *initial_value_ptr,
+ const Value *object_address_ptr)
+ : m_dwarf_expression(dwarf_expression), m_exe_ctx(exe_ctx),
+ m_reg_ctx(reg_ctx), m_initial_value_ptr(initial_value_ptr),
+ m_object_address_ptr(object_address_ptr) {}
+
+static bool ReadRegisterValueAsScalar(RegisterContext *reg_ctx,
+ lldb::RegisterKind reg_kind,
+ uint32_t reg_num, Status *error_ptr,
+ Value &value) {
+ if (reg_ctx == nullptr) {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat("No register context in frame.\n");
+ } else {
+ uint32_t native_reg =
+ reg_ctx->ConvertRegisterKindToRegisterNumber(reg_kind, reg_num);
+ if (native_reg == LLDB_INVALID_REGNUM) {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat("Unable to convert register "
+ "kind=%u reg_num=%u to a native "
+ "register number.\n",
+ reg_kind, reg_num);
+ } else {
+ const RegisterInfo *reg_info =
+ reg_ctx->GetRegisterInfoAtIndex(native_reg);
+ RegisterValue reg_value;
+ if (reg_ctx->ReadRegister(reg_info, reg_value)) {
+ if (reg_value.GetScalarValue(value.GetScalar())) {
+ value.SetValueType(Value::ValueType::Scalar);
+ value.SetContext(Value::ContextType::RegisterInfo,
+ const_cast<RegisterInfo *>(reg_info));
+ if (error_ptr)
+ error_ptr->Clear();
+ return true;
+ } else {
+ // If we get this error, then we need to implement a value buffer in
+ // the dwarf expression evaluation function...
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "register %s can't be converted to a scalar value",
+ reg_info->name);
+ }
+ } else {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat("register %s is not available",
+ reg_info->name);
+ }
+ }
+ }
+ return false;
+}
+
+static bool Evaluate_DW_OP_entry_value(std::vector<Value> &stack,
+ ExecutionContext *exe_ctx,
+ RegisterContext *reg_ctx,
+ const DataExtractor &opcodes,
+ lldb::offset_t &opcode_offset,
+ Status *error_ptr, Log *log) {
+ // DW_OP_entry_value(sub-expr) describes the location a variable had upon
+ // function entry: this variable location is presumed to be optimized out at
+ // the current PC value. The caller of the function may have call site
+ // information that describes an alternate location for the variable (e.g. a
+ // constant literal, or a spilled stack value) in the parent frame.
+ //
+ // Example (this is pseudo-code & pseudo-DWARF, but hopefully illustrative):
+ //
+ // void child(int &sink, int x) {
+ // ...
+ // /* "x" gets optimized out. */
+ //
+ // /* The location of "x" here is: DW_OP_entry_value($reg2). */
+ // ++sink;
+ // }
+ //
+ // void parent() {
+ // int sink;
+ //
+ // /*
+ // * The callsite information emitted here is:
+ // *
+ // * DW_TAG_call_site
+ // * DW_AT_return_pc ... (for "child(sink, 123);")
+ // * DW_TAG_call_site_parameter (for "sink")
+ // * DW_AT_location ($reg1)
+ // * DW_AT_call_value ($SP - 8)
+ // * DW_TAG_call_site_parameter (for "x")
+ // * DW_AT_location ($reg2)
+ // * DW_AT_call_value ($literal 123)
+ // *
+ // * DW_TAG_call_site
+ // * DW_AT_return_pc ... (for "child(sink, 456);")
+ // * ...
+ // */
+ // child(sink, 123);
+ // child(sink, 456);
+ // }
+ //
+ // When the program stops at "++sink" within `child`, the debugger determines
+ // the call site by analyzing the return address. Once the call site is found,
+ // the debugger determines which parameter is referenced by DW_OP_entry_value
+ // and evaluates the corresponding location for that parameter in `parent`.
+
+ // 1. Find the function which pushed the current frame onto the stack.
+ if ((!exe_ctx || !exe_ctx->HasTargetScope()) || !reg_ctx) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no exe/reg context");
+ return false;
+ }
+
+ StackFrame *current_frame = exe_ctx->GetFramePtr();
+ Thread *thread = exe_ctx->GetThreadPtr();
+ if (!current_frame || !thread) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current frame/thread");
+ return false;
+ }
+
+ Target &target = exe_ctx->GetTargetRef();
+ StackFrameSP parent_frame = nullptr;
+ addr_t return_pc = LLDB_INVALID_ADDRESS;
+ uint32_t current_frame_idx = current_frame->GetFrameIndex();
+ uint32_t num_frames = thread->GetStackFrameCount();
+ for (uint32_t parent_frame_idx = current_frame_idx + 1;
+ parent_frame_idx < num_frames; ++parent_frame_idx) {
+ parent_frame = thread->GetStackFrameAtIndex(parent_frame_idx);
+ // Require a valid sequence of frames.
+ if (!parent_frame)
+ break;
+
+ // Record the first valid return address, even if this is an inlined frame,
+ // in order to look up the associated call edge in the first non-inlined
+ // parent frame.
+ if (return_pc == LLDB_INVALID_ADDRESS) {
+ return_pc = parent_frame->GetFrameCodeAddress().GetLoadAddress(&target);
+ LLDB_LOG(log,
+ "Evaluate_DW_OP_entry_value: immediate ancestor with pc = {0:x}",
+ return_pc);
+ }
+
+ // If we've found an inlined frame, skip it (these have no call site
+ // parameters).
+ if (parent_frame->IsInlined())
+ continue;
+
+ // We've found the first non-inlined parent frame.
+ break;
+ }
+ if (!parent_frame || !parent_frame->GetRegisterContext()) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent frame with reg ctx");
+ return false;
+ }
+
+ Function *parent_func =
+ parent_frame->GetSymbolContext(eSymbolContextFunction).function;
+ if (!parent_func) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no parent function");
+ return false;
+ }
+
+ // 2. Find the call edge in the parent function responsible for creating the
+ // current activation.
+ Function *current_func =
+ current_frame->GetSymbolContext(eSymbolContextFunction).function;
+ if (!current_func) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no current function");
+ return false;
+ }
+
+ CallEdge *call_edge = nullptr;
+ ModuleList &modlist = target.GetImages();
+ ExecutionContext parent_exe_ctx = *exe_ctx;
+ parent_exe_ctx.SetFrameSP(parent_frame);
+ if (!parent_frame->IsArtificial()) {
+ // If the parent frame is not artificial, the current activation may be
+ // produced by an ambiguous tail call. In this case, refuse to proceed.
+ call_edge = parent_func->GetCallEdgeForReturnAddress(return_pc, target);
+ if (!call_edge) {
+ LLDB_LOG(log,
+ "Evaluate_DW_OP_entry_value: no call edge for retn-pc = {0:x} "
+ "in parent frame {1}",
+ return_pc, parent_func->GetName());
+ return false;
+ }
+ Function *callee_func = call_edge->GetCallee(modlist, parent_exe_ctx);
+ if (callee_func != current_func) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: ambiguous call sequence, "
+ "can't find real parent frame");
+ return false;
+ }
+ } else {
+ // The StackFrameList solver machinery has deduced that an unambiguous tail
+ // call sequence that produced the current activation. The first edge in
+ // the parent that points to the current function must be valid.
+ for (auto &edge : parent_func->GetTailCallingEdges()) {
+ if (edge->GetCallee(modlist, parent_exe_ctx) == current_func) {
+ call_edge = edge.get();
+ break;
+ }
+ }
+ }
+ if (!call_edge) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: no unambiguous edge from parent "
+ "to current function");
+ return false;
+ }
+
+ // 3. Attempt to locate the DW_OP_entry_value expression in the set of
+ // available call site parameters. If found, evaluate the corresponding
+ // parameter in the context of the parent frame.
+ const uint32_t subexpr_len = opcodes.GetULEB128(&opcode_offset);
+ const void *subexpr_data = opcodes.GetData(&opcode_offset, subexpr_len);
+ if (!subexpr_data) {
+ LLDB_LOG(log, "Evaluate_DW_OP_entry_value: subexpr could not be read");
+ return false;
+ }
+
+ const CallSiteParameter *matched_param = nullptr;
+ for (const CallSiteParameter ¶m : call_edge->GetCallSiteParameters()) {
+ DataExtractor param_subexpr_extractor;
+ if (!param.LocationInCallee.GetExpressionData(param_subexpr_extractor))
+ continue;
+ lldb::offset_t param_subexpr_offset = 0;
+ const void *param_subexpr_data =
+ param_subexpr_extractor.GetData(¶m_subexpr_offset, subexpr_len);
+ if (!param_subexpr_data ||
+ param_subexpr_extractor.BytesLeft(param_subexpr_offset) != 0)
+ continue;
+
+ // At this point, the DW_OP_entry_value sub-expression and the callee-side
+ // expression in the call site parameter are known to have the same length.
+ // Check whether they are equal.
+ //
+ // Note that an equality check is sufficient: the contents of the
+ // DW_OP_entry_value subexpression are only used to identify the right call
+ // site parameter in the parent, and do not require any special handling.
+ if (memcmp(subexpr_data, param_subexpr_data, subexpr_len) == 0) {
+ matched_param = ¶m;
+ break;
+ }
+ }
+ if (!matched_param) {
+ LLDB_LOG(log,
+ "Evaluate_DW_OP_entry_value: no matching call site param found");
+ return false;
+ }
+
+ // TODO: Add support for DW_OP_push_object_address within a DW_OP_entry_value
+ // subexpresion whenever llvm does.
+ Value result;
+ const DWARFExpression ¶m_expr = matched_param->LocationInCaller;
+ if (!param_expr.Evaluate(&parent_exe_ctx,
+ parent_frame->GetRegisterContext().get(),
+ /*loclist_base_addr=*/LLDB_INVALID_ADDRESS,
+ /*initial_value_ptr=*/nullptr,
+ /*object_address_ptr=*/nullptr, result, error_ptr)) {
+ LLDB_LOG(log,
+ "Evaluate_DW_OP_entry_value: call site param evaluation failed");
+ return false;
+ }
+
+ stack.push_back(result);
+ return true;
+}
+
+bool DWARFEvaluator::Evaluate(Value &result, Status *error_ptr) {
+ DataExtractor opcodes;
+ if (!m_dwarf_expression.GetExpressionData(opcodes)) {
+ if (error_ptr)
+ error_ptr->SetErrorString(
+ "no location, value may have been optimized out");
+ return false;
+ }
+ return Evaluate(opcodes, result, error_ptr);
+}
+
+bool DWARFEvaluator::Evaluate(const DataExtractor &opcodes, Value &result,
+ Status *error_ptr) {
+ if (opcodes.GetByteSize() == 0) {
+ if (error_ptr)
+ error_ptr->SetErrorString(
+ "no location, value may have been optimized out");
+ return false;
+ }
+ std::vector<Value> stack;
+
+ Process *process = nullptr;
+ StackFrame *frame = nullptr;
+
+ if (m_exe_ctx) {
+ process = m_exe_ctx->GetProcessPtr();
+ frame = m_exe_ctx->GetFramePtr();
+ }
+ if (m_reg_ctx == nullptr && frame)
+ m_reg_ctx = frame->GetRegisterContext().get();
+
+ if (m_initial_value_ptr)
+ stack.push_back(*m_initial_value_ptr);
+
+ lldb::offset_t offset = 0;
+
+ /// Insertion point for evaluating multi-piece expression.
+ uint64_t op_piece_offset = 0;
+ Value pieces; // Used for DW_OP_piece
+
+ Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
+
+ uint8_t _opcode = 0;
+
+ while (opcodes.ValidOffset(offset)) {
+ const lldb::offset_t op_offset = offset;
+ const uint8_t op = opcodes.GetU8(&offset);
+ _opcode = op;
+
+ if (log && log->GetVerbose()) {
+ size_t count = stack.size();
+ LLDB_LOGF(log, "Stack before operation has %" PRIu64 " values:",
+ (uint64_t)count);
+ for (size_t i = 0; i < count; ++i) {
+ StreamString new_value;
+ new_value.Printf("[%" PRIu64 "]", (uint64_t)i);
+ stack[i].Dump(&new_value);
+ LLDB_LOGF(log, " %s", new_value.GetData());
+ }
+ LLDB_LOGF(log, "0x%8.8" PRIx64 ": %s", op_offset,
+ DW_OP_value_to_name(op));
+ }
+
+ if (!Evaluate(op, process, frame, stack, opcodes, offset, pieces,
+ op_piece_offset, log, error_ptr))
+ return false;
+ }
+
+ if (stack.empty()) {
+ // Nothing on the stack, check if we created a piece value from DW_OP_piece
+ // or DW_OP_bit_piece opcodes
+ if (pieces.GetBuffer().GetByteSize())
+ result = pieces;
+ else {
+ if (error_ptr)
+ error_ptr->SetErrorString("Stack empty after evaluation.");
+ return false;
+ }
+ } else {
+ if (log && log->GetVerbose()) {
+ size_t count = stack.size();
+ LLDB_LOGF(log, "Stack after operation has %" PRIu64 " values:",
+ (uint64_t)count);
+ for (size_t i = 0; i < count; ++i) {
+ StreamString new_value;
+ new_value.Printf("[%" PRIu64 "]", (uint64_t)i);
+ stack[i].Dump(&new_value);
+ LLDB_LOGF(log, " %s", new_value.GetData());
+ }
+ }
+ result = stack.back();
+ }
+ return true; // Return true on success
+}
+
+bool DWARFEvaluator::Evaluate(const uint8_t op, Process *process,
+ StackFrame *frame, std::vector<Value> &stack,
+ const DataExtractor &opcodes,
+ lldb::offset_t &offset, Value &pieces,
+ uint64_t &op_piece_offset, Log *log,
+ Status *error_ptr) {
+ Value tmp;
+ uint32_t reg_num;
+
+ lldb::ModuleSP module_sp = m_dwarf_expression.GetModule();
+ const DWARFUnit *dwarf_cu = m_dwarf_expression.GetDWARFCompileUnit();
+ const lldb::RegisterKind reg_kind = m_dwarf_expression.GetRegisterKind();
+
+ switch (op) {
+ // The DW_OP_addr operation has a single operand that encodes a machine
+ // address and whose size is the size of an address on the target machine.
+ case DW_OP_addr:
+ stack.push_back(Scalar(opcodes.GetAddress(&offset)));
+ stack.back().SetValueType(Value::ValueType::FileAddress);
+ // Convert the file address to a load address, so subsequent
+ // DWARF operators can operate on it.
+ if (frame)
+ stack.back().ConvertToLoadAddress(module_sp.get(),
+ frame->CalculateTarget().get());
+ break;
+
+ // The DW_OP_addr_sect_offset4 is used for any location expressions in
+ // shared libraries that have a location like:
+ // DW_OP_addr(0x1000)
+ // If this address resides in a shared library, then this virtual address
+ // won't make sense when it is evaluated in the context of a running
+ // process where shared libraries have been slid. To account for this, this
+ // new address type where we can store the section pointer and a 4 byte
+ // offset.
+ // case DW_OP_addr_sect_offset4:
+ // {
+ // result_type = eResultTypeFileAddress;
+ // lldb::Section *sect = (lldb::Section
+ // *)opcodes.GetMaxU64(&offset, sizeof(void *));
+ // lldb::addr_t sect_offset = opcodes.GetU32(&offset);
+ //
+ // Address so_addr (sect, sect_offset);
+ // lldb::addr_t load_addr = so_addr.GetLoadAddress();
+ // if (load_addr != LLDB_INVALID_ADDRESS)
+ // {
+ // // We successfully resolve a file address to a load
+ // // address.
+ // stack.push_back(load_addr);
+ // break;
+ // }
+ // else
+ // {
+ // // We were able
+ // if (error_ptr)
+ // error_ptr->SetErrorStringWithFormat ("Section %s in
+ // %s is not currently loaded.\n",
+ // sect->GetName().AsCString(),
+ // sect->GetModule()->GetFileSpec().GetFilename().AsCString());
+ // return false;
+ // }
+ // }
+ // break;
+
+ // OPCODE: DW_OP_deref
+ // OPERANDS: none
+ // DESCRIPTION: Pops the top stack entry and treats it as an address.
+ // The value retrieved from that address is pushed. The size of the data
+ // retrieved from the dereferenced address is the size of an address on the
+ // target machine.
+ case DW_OP_deref: {
+ if (stack.empty()) {
+ if (error_ptr)
+ error_ptr->SetErrorString("Expression stack empty for DW_OP_deref.");
+ return false;
+ }
+ Value::ValueType value_type = stack.back().GetValueType();
+ switch (value_type) {
+ case Value::ValueType::HostAddress: {
+ void *src = (void *)stack.back().GetScalar().ULongLong();
+ intptr_t ptr;
+ ::memcpy(&ptr, src, sizeof(void *));
+ stack.back().GetScalar() = ptr;
+ stack.back().ClearContext();
+ } break;
+ case Value::ValueType::FileAddress: {
+ auto file_addr = stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
+ if (!module_sp) {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "need module to resolve file address for DW_OP_deref");
+ return false;
+ }
+ Address so_addr;
+ if (!module_sp->ResolveFileAddress(file_addr, so_addr)) {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "failed to resolve file address in module");
+ return false;
+ }
+ addr_t load_Addr = so_addr.GetLoadAddress(m_exe_ctx->GetTargetPtr());
+ if (load_Addr == LLDB_INVALID_ADDRESS) {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat("failed to resolve load address");
+ return false;
+ }
+ stack.back().GetScalar() = load_Addr;
+ stack.back().SetValueType(Value::ValueType::LoadAddress);
+ // Fall through to load address code below...
+ }
+ LLVM_FALLTHROUGH;
+ case Value::ValueType::LoadAddress:
+ if (m_exe_ctx) {
+ if (process) {
+ lldb::addr_t pointer_addr =
+ stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
+ Status error;
+ lldb::addr_t pointer_value =
+ process->ReadPointerFromMemory(pointer_addr, error);
+ if (pointer_value != LLDB_INVALID_ADDRESS) {
+ stack.back().GetScalar() = pointer_value;
+ stack.back().ClearContext();
+ } else {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "Failed to dereference pointer from 0x%" PRIx64
+ " for DW_OP_deref: %s\n",
+ pointer_addr, error.AsCString());
+ return false;
+ }
+ } else {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "NULL process for DW_OP_deref.\n");
+ return false;
+ }
+ } else {
+ if (error_ptr)
+ error_ptr->SetErrorStringWithFormat(
+ "NULL execution context for DW_OP_deref.\n");
+ return false;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ } break;
+
+ // OPCODE: DW_OP_deref_size
+ // OPERANDS: 1
+ // 1 - uint8_t that specifies the size of the data to dereference.
+ // DESCRIPTION: Behaves like the DW_OP_deref operation: it pops the top
+ // stack entry and treats it as an address. The value retrieved from that
+ // address is pushed. In the DW_OP_deref_size operation, however, the size
+ // in bytes of the data retrieved from the dereferenced address is
+ // specified by the single operand. This operand is a 1-byte unsigned
+ // integral constant whose value may not be larger than the size of an
+ // address on the target machine. The data retrieved is zero extended to
+ // the size of an address on the target machine before being pushed on the
+ // expression stack.
+ case DW_OP_deref_size: {
+ if (stack.empty()) {
+ if (error_ptr)
+ error_ptr->SetErrorString(
+ "Expression stack empty for DW_OP_deref_size.");
+ return false;
+ }
+ uint8_t size = opcodes.GetU8(&offset);
+ Value::ValueType value_type = stack.back().GetValueType();
+ switch (value_type) {
+ case Value::ValueType::HostAddress: {
+ void *src = (void *)stack.back().GetScalar().ULongLong();
+ intptr_t ptr;
+ ::memcpy(&ptr, src, sizeof(void *));
+ // I can't decide whether the size operand should apply to the bytes in
+ // their
+ // lldb-host endianness or the target endianness.. I doubt this'll ever
+ // come up but I'll opt for assuming big endian regardless.
+ switch (size) {
+ case 1:
+ ptr = ptr & 0xff;
+ break;