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[lldb][TypeSystemClang] Make AsmLabel parameter a llvm::StringRef #151355
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[lldb][TypeSystemClang] Make AsmLabel parameter a llvm::StringRef #151355
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…string> Split out from llvm#148877 This patch prepares `TypeSystemClang` APIs to take `AsmLabel`s which concatenated strings (hence `std::string`) instead of a plain `const char*`.
@llvm/pr-subscribers-lldb Author: Michael Buch (Michael137) ChangesSplit out from #148877 This patch prepares Full diff: https://github.com/llvm/llvm-project/pull/151355.diff 8 Files Affected:
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
index 9f77fbc1d2434..a6c4334bf2e59 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
@@ -1991,7 +1991,7 @@ void ClangExpressionDeclMap::AddContextClassType(NameSearchContext &context,
const bool is_artificial = false;
CXXMethodDecl *method_decl = m_clang_ast_context->AddMethodToCXXRecordType(
- copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", nullptr,
+ copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", std::nullopt,
method_type, lldb::eAccessPublic, is_virtual, is_static, is_inline,
is_explicit, is_attr_used, is_artificial);
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
index ba65f50a44d10..677d66abd2dfc 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -249,6 +249,14 @@ static unsigned GetCXXMethodCVQuals(const DWARFDIE &subprogram,
return cv_quals;
}
+static std::optional<std::string> MakeLLDBFuncAsmLabel(const DWARFDIE &die) {
+ char const *name = die.GetMangledName(/*substitute_name_allowed*/ false);
+ if (!name)
+ return std::nullopt;
+
+ return name;
+}
+
TypeSP DWARFASTParserClang::ParseTypeFromClangModule(const SymbolContext &sc,
const DWARFDIE &die,
Log *log) {
@@ -1231,7 +1239,7 @@ std::pair<bool, TypeSP> DWARFASTParserClang::ParseCXXMethod(
clang::CXXMethodDecl *cxx_method_decl = m_ast.AddMethodToCXXRecordType(
class_opaque_type.GetOpaqueQualType(), attrs.name.GetCString(),
- attrs.mangled_name, clang_type, accessibility, attrs.is_virtual,
+ MakeLLDBFuncAsmLabel(die), clang_type, accessibility, attrs.is_virtual,
is_static, attrs.is_inline, attrs.is_explicit, is_attr_used,
attrs.is_artificial);
@@ -1384,7 +1392,7 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
ignore_containing_context ? m_ast.GetTranslationUnitDecl()
: containing_decl_ctx,
GetOwningClangModule(die), name, clang_type, attrs.storage,
- attrs.is_inline);
+ attrs.is_inline, MakeLLDBFuncAsmLabel(die));
std::free(name_buf);
if (has_template_params) {
@@ -1394,7 +1402,7 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
ignore_containing_context ? m_ast.GetTranslationUnitDecl()
: containing_decl_ctx,
GetOwningClangModule(die), attrs.name.GetStringRef(), clang_type,
- attrs.storage, attrs.is_inline);
+ attrs.storage, attrs.is_inline, /*asm_label=*/std::nullopt);
clang::FunctionTemplateDecl *func_template_decl =
m_ast.CreateFunctionTemplateDecl(
containing_decl_ctx, GetOwningClangModule(die),
@@ -1406,20 +1414,6 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
lldbassert(function_decl);
if (function_decl) {
- // Attach an asm(<mangled_name>) label to the FunctionDecl.
- // This ensures that clang::CodeGen emits function calls
- // using symbols that are mangled according to the DW_AT_linkage_name.
- // If we didn't do this, the external symbols wouldn't exactly
- // match the mangled name LLDB knows about and the IRExecutionUnit
- // would have to fall back to searching object files for
- // approximately matching function names. The motivating
- // example is generating calls to ABI-tagged template functions.
- // This is done separately for member functions in
- // AddMethodToCXXRecordType.
- if (attrs.mangled_name)
- function_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(
- m_ast.getASTContext(), attrs.mangled_name, /*literal=*/false));
-
LinkDeclContextToDIE(function_decl, die);
const clang::FunctionProtoType *function_prototype(
diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp b/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp
index 702ec5e5c9ea9..bce721c149fee 100644
--- a/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp
@@ -88,7 +88,7 @@ struct CreateMethodDecl : public TypeVisitorCallbacks {
MethodOptions::CompilerGenerated;
function_decl = m_clang.AddMethodToCXXRecordType(
parent_ty, proc_name,
- /*mangled_name=*/nullptr, func_ct, /*access=*/access_type,
+ /*mangled_name=*/std::nullopt, func_ct, /*access=*/access_type,
/*is_virtual=*/is_virtual, /*is_static=*/is_static,
/*is_inline=*/false, /*is_explicit=*/false,
/*is_attr_used=*/false, /*is_artificial=*/is_artificial);
@@ -903,7 +903,7 @@ PdbAstBuilder::CreateFunctionDecl(PdbCompilandSymId func_id,
if (!function_decl) {
function_decl = m_clang.AddMethodToCXXRecordType(
parent_opaque_ty, func_name,
- /*mangled_name=*/nullptr, func_ct,
+ /*mangled_name=*/std::nullopt, func_ct,
/*access=*/lldb::AccessType::eAccessPublic,
/*is_virtual=*/false, /*is_static=*/false,
/*is_inline=*/false, /*is_explicit=*/false,
@@ -913,7 +913,7 @@ PdbAstBuilder::CreateFunctionDecl(PdbCompilandSymId func_id,
} else {
function_decl = m_clang.CreateFunctionDeclaration(
parent, OptionalClangModuleID(), func_name, func_ct, func_storage,
- is_inline);
+ is_inline, /*asm_label=*/std::nullopt);
CreateFunctionParameters(func_id, *function_decl, param_count);
}
return function_decl;
diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/UdtRecordCompleter.cpp b/lldb/source/Plugins/SymbolFile/NativePDB/UdtRecordCompleter.cpp
index 807ee5b30779c..5e77ea7f85603 100644
--- a/lldb/source/Plugins/SymbolFile/NativePDB/UdtRecordCompleter.cpp
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/UdtRecordCompleter.cpp
@@ -111,9 +111,8 @@ void UdtRecordCompleter::AddMethod(llvm::StringRef name, TypeIndex type_idx,
bool is_artificial = (options & MethodOptions::CompilerGenerated) ==
MethodOptions::CompilerGenerated;
m_ast_builder.clang().AddMethodToCXXRecordType(
- derived_opaque_ty, name.data(), nullptr, method_ct,
- access_type, attrs.isVirtual(), attrs.isStatic(), false, false, false,
- is_artificial);
+ derived_opaque_ty, name.data(), std::nullopt, method_ct, access_type,
+ attrs.isVirtual(), attrs.isStatic(), false, false, false, is_artificial);
m_cxx_record_map[derived_opaque_ty].insert({name, method_ct});
}
diff --git a/lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp b/lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
index 0090d8ff03ab6..548a3ed25111f 100644
--- a/lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
+++ b/lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
@@ -954,7 +954,8 @@ PDBASTParser::GetDeclForSymbol(const llvm::pdb::PDBSymbol &symbol) {
auto decl = m_ast.CreateFunctionDeclaration(
decl_context, OptionalClangModuleID(), name,
- type->GetForwardCompilerType(), storage, func->hasInlineAttribute());
+ type->GetForwardCompilerType(), storage, func->hasInlineAttribute(),
+ /*asm_label=*/std::nullopt);
std::vector<clang::ParmVarDecl *> params;
if (std::unique_ptr<PDBSymbolTypeFunctionSig> sig = func->getSignature()) {
@@ -1446,8 +1447,8 @@ PDBASTParser::AddRecordMethod(lldb_private::SymbolFile &symbol_file,
// TODO: get mangled name for the method.
return m_ast.AddMethodToCXXRecordType(
record_type.GetOpaqueQualType(), name.c_str(),
- /*mangled_name*/ nullptr, method_comp_type, access, method.isVirtual(),
- method.isStatic(), method.hasInlineAttribute(),
+ /*mangled_name*/ std::nullopt, method_comp_type, access,
+ method.isVirtual(), method.isStatic(), method.hasInlineAttribute(),
/*is_explicit*/ false, // FIXME: Need this field in CodeView.
/*is_attr_used*/ false,
/*is_artificial*/ method.isCompilerGenerated());
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
index 256952dcf9085..ba960e19795dc 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
@@ -2137,7 +2137,8 @@ std::string TypeSystemClang::GetTypeNameForDecl(const NamedDecl *named_decl,
FunctionDecl *TypeSystemClang::CreateFunctionDeclaration(
clang::DeclContext *decl_ctx, OptionalClangModuleID owning_module,
llvm::StringRef name, const CompilerType &function_clang_type,
- clang::StorageClass storage, bool is_inline) {
+ clang::StorageClass storage, bool is_inline,
+ std::optional<std::string> asm_label) {
FunctionDecl *func_decl = nullptr;
ASTContext &ast = getASTContext();
if (!decl_ctx)
@@ -2158,6 +2159,21 @@ FunctionDecl *TypeSystemClang::CreateFunctionDeclaration(
func_decl->setConstexprKind(isConstexprSpecified
? ConstexprSpecKind::Constexpr
: ConstexprSpecKind::Unspecified);
+
+ // Attach an asm(<mangled_name>) label to the FunctionDecl.
+ // This ensures that clang::CodeGen emits function calls
+ // using symbols that are mangled according to the DW_AT_linkage_name.
+ // If we didn't do this, the external symbols wouldn't exactly
+ // match the mangled name LLDB knows about and the IRExecutionUnit
+ // would have to fall back to searching object files for
+ // approximately matching function names. The motivating
+ // example is generating calls to ABI-tagged template functions.
+ // This is done separately for member functions in
+ // AddMethodToCXXRecordType.
+ if (asm_label)
+ func_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(ast, *asm_label,
+ /*literal=*/true));
+
SetOwningModule(func_decl, owning_module);
decl_ctx->addDecl(func_decl);
@@ -7651,7 +7667,7 @@ TypeSystemClang::CreateParameterDeclarations(
clang::CXXMethodDecl *TypeSystemClang::AddMethodToCXXRecordType(
lldb::opaque_compiler_type_t type, llvm::StringRef name,
- const char *mangled_name, const CompilerType &method_clang_type,
+ std::optional<std::string> asm_label, const CompilerType &method_clang_type,
lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline,
bool is_explicit, bool is_attr_used, bool is_artificial) {
if (!type || !method_clang_type.IsValid() || name.empty())
@@ -7784,10 +7800,9 @@ clang::CXXMethodDecl *TypeSystemClang::AddMethodToCXXRecordType(
if (is_attr_used)
cxx_method_decl->addAttr(clang::UsedAttr::CreateImplicit(getASTContext()));
- if (mangled_name != nullptr) {
+ if (asm_label)
cxx_method_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(
- getASTContext(), mangled_name, /*literal=*/false));
- }
+ getASTContext(), *asm_label, /*literal=*/true));
// Parameters on member function declarations in DWARF generally don't
// have names, so we omit them when creating the ParmVarDecls.
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
index 63dee9dceded3..dcf77f9ec1cb8 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
@@ -477,7 +477,8 @@ class TypeSystemClang : public TypeSystem {
clang::FunctionDecl *CreateFunctionDeclaration(
clang::DeclContext *decl_ctx, OptionalClangModuleID owning_module,
llvm::StringRef name, const CompilerType &function_Type,
- clang::StorageClass storage, bool is_inline);
+ clang::StorageClass storage, bool is_inline,
+ std::optional<std::string> asm_label);
CompilerType
CreateFunctionType(const CompilerType &result_type,
@@ -1001,7 +1002,7 @@ class TypeSystemClang : public TypeSystem {
clang::CXXMethodDecl *AddMethodToCXXRecordType(
lldb::opaque_compiler_type_t type, llvm::StringRef name,
- const char *mangled_name, const CompilerType &method_type,
+ std::optional<std::string> mangled_name, const CompilerType &method_type,
lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline,
bool is_explicit, bool is_attr_used, bool is_artificial);
diff --git a/lldb/unittests/Symbol/TestTypeSystemClang.cpp b/lldb/unittests/Symbol/TestTypeSystemClang.cpp
index 71930ab54f409..588361e65c7a1 100644
--- a/lldb/unittests/Symbol/TestTypeSystemClang.cpp
+++ b/lldb/unittests/Symbol/TestTypeSystemClang.cpp
@@ -869,7 +869,7 @@ TEST_F(TestTypeSystemClang, TestFunctionTemplateConstruction) {
CompilerType clang_type = m_ast->CreateFunctionType(int_type, {}, false, 0U);
FunctionDecl *func = m_ast->CreateFunctionDeclaration(
TU, OptionalClangModuleID(), "foo", clang_type, StorageClass::SC_None,
- false);
+ false, std::nullopt);
TypeSystemClang::TemplateParameterInfos empty_params;
// Create the actual function template.
@@ -900,7 +900,7 @@ TEST_F(TestTypeSystemClang, TestFunctionTemplateInRecordConstruction) {
// 2. It is mirroring the behavior of DWARFASTParserClang::ParseSubroutine.
FunctionDecl *func = m_ast->CreateFunctionDeclaration(
TU, OptionalClangModuleID(), "foo", clang_type, StorageClass::SC_None,
- false);
+ false, std::nullopt);
TypeSystemClang::TemplateParameterInfos empty_params;
// Create the actual function template.
@@ -938,7 +938,7 @@ TEST_F(TestTypeSystemClang, TestDeletingImplicitCopyCstrDueToMoveCStr) {
bool is_attr_used = false;
bool is_artificial = false;
m_ast->AddMethodToCXXRecordType(
- t.GetOpaqueQualType(), class_name, nullptr, function_type,
+ t.GetOpaqueQualType(), class_name, std::nullopt, function_type,
lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
is_explicit, is_attr_used, is_artificial);
@@ -975,7 +975,7 @@ TEST_F(TestTypeSystemClang, TestNotDeletingUserCopyCstrDueToMoveCStr) {
CompilerType function_type = m_ast->CreateFunctionType(
return_type, args, /*variadic=*/false, /*quals*/ 0U);
m_ast->AddMethodToCXXRecordType(
- t.GetOpaqueQualType(), class_name, nullptr, function_type,
+ t.GetOpaqueQualType(), class_name, std::nullopt, function_type,
lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
is_explicit, is_attr_used, is_artificial);
}
@@ -987,7 +987,7 @@ TEST_F(TestTypeSystemClang, TestNotDeletingUserCopyCstrDueToMoveCStr) {
m_ast->CreateFunctionType(return_type, args,
/*variadic=*/false, /*quals*/ 0U);
m_ast->AddMethodToCXXRecordType(
- t.GetOpaqueQualType(), class_name, nullptr, function_type,
+ t.GetOpaqueQualType(), class_name, std::nullopt, function_type,
lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
is_explicit, is_attr_used, is_artificial);
}
@@ -1098,7 +1098,7 @@ TEST_F(TestTypeSystemClang, AddMethodToCXXRecordType_ParmVarDecls) {
m_ast->CreateFunctionType(return_type, param_types,
/*variadic=*/false, /*quals*/ 0U);
m_ast->AddMethodToCXXRecordType(
- t.GetOpaqueQualType(), "myFunc", nullptr, function_type,
+ t.GetOpaqueQualType(), "myFunc", std::nullopt, function_type,
lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
is_explicit, is_attr_used, is_artificial);
|
// This is done separately for member functions in | ||
// AddMethodToCXXRecordType. | ||
if (asm_label) | ||
func_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(ast, *asm_label, |
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Is it valid for asm_label
to be the empty string? If not, you'll need to check for that here too. Alternatively, you could make the parameter type std::string
and drop the optional entirely.
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I asked myself that same question as I was splitting this out. I agree std::string
should suffice
…#148877) LLDB currently attaches `AsmLabel`s to `FunctionDecl`s such that that the `IRExecutionUnit` can determine which mangled name to call (we can't rely on Clang deriving the correct mangled name to call because the debug-info AST doesn't contain all the info that would be encoded in the DWARF linkage names). However, we don't attach `AsmLabel`s for structors because they have multiple variants and thus it's not clear which mangled name to use. In the [RFC on fixing expression evaluation of abi-tagged structors](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816) we discussed encoding the structor variant into the `AsmLabel`s. Specifically in [this thread](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816/7) we discussed that the contents of the `AsmLabel` are completely under LLDB's control and we could make use of it to uniquely identify a function by encoding the exact module and DIE that the function is associated with (mangled names need not be enough since two identical mangled symbols may live in different modules). So if we already have a custom `AsmLabel` format, we can encode the structor variant in a follow-up (the current idea is to append the structor variant as a suffix to our custom `AsmLabel` when Clang emits the mangled name into the JITted IR). Then we would just have to teach the `IRExecutionUnit` to pick the correct structor variant DIE during symbol resolution. The draft of this is available [here](#149827) This patch sets up the infrastructure for the custom `AsmLabel` format by encoding the module id, DIE id and mangled name in it. **Implementation** The flow is as follows: 1. Create the label in `DWARFASTParserClang`. The format is: `$__lldb_func:module_id:die_id:mangled_name` 2. When resolving external symbols in `IRExecutionUnit`, we parse this label and then do a lookup by DIE ID (or mangled name into the module if the encoded DIE is a declaration). Depends on #151355
…n AsmLabels (#148877) LLDB currently attaches `AsmLabel`s to `FunctionDecl`s such that that the `IRExecutionUnit` can determine which mangled name to call (we can't rely on Clang deriving the correct mangled name to call because the debug-info AST doesn't contain all the info that would be encoded in the DWARF linkage names). However, we don't attach `AsmLabel`s for structors because they have multiple variants and thus it's not clear which mangled name to use. In the [RFC on fixing expression evaluation of abi-tagged structors](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816) we discussed encoding the structor variant into the `AsmLabel`s. Specifically in [this thread](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816/7) we discussed that the contents of the `AsmLabel` are completely under LLDB's control and we could make use of it to uniquely identify a function by encoding the exact module and DIE that the function is associated with (mangled names need not be enough since two identical mangled symbols may live in different modules). So if we already have a custom `AsmLabel` format, we can encode the structor variant in a follow-up (the current idea is to append the structor variant as a suffix to our custom `AsmLabel` when Clang emits the mangled name into the JITted IR). Then we would just have to teach the `IRExecutionUnit` to pick the correct structor variant DIE during symbol resolution. The draft of this is available [here](llvm/llvm-project#149827) This patch sets up the infrastructure for the custom `AsmLabel` format by encoding the module id, DIE id and mangled name in it. **Implementation** The flow is as follows: 1. Create the label in `DWARFASTParserClang`. The format is: `$__lldb_func:module_id:die_id:mangled_name` 2. When resolving external symbols in `IRExecutionUnit`, we parse this label and then do a lookup by DIE ID (or mangled name into the module if the encoded DIE is a declaration). Depends on llvm/llvm-project#151355
This was added purely for the needs of LLDB. However, starting with llvm#151355 and llvm#148877 we no longer create literal AsmLabels in LLDB either. So this is unused and we can get rid of it. In the near future LLDB will want to add special support for mangling `AsmLabel`s, and the "literal label" codepath in the mangler made this more cumbersome.
…(#151858) This was added purely for the needs of LLDB. However, starting with llvm/llvm-project#151355 and llvm/llvm-project#148877 we no longer create literal AsmLabels in LLDB either. So this is unused and we can get rid of it. In the near future LLDB will want to add special support for mangling `AsmLabel`s (specifically llvm/llvm-project#149827).
…vm#151355) Split out from llvm#148877 This patch prepares `TypeSystemClang` APIs to take `AsmLabel`s which concatenated strings (hence `std::string`) instead of a plain `const char*`. (cherry picked from commit 7410f6d)
…llvm#148877) LLDB currently attaches `AsmLabel`s to `FunctionDecl`s such that that the `IRExecutionUnit` can determine which mangled name to call (we can't rely on Clang deriving the correct mangled name to call because the debug-info AST doesn't contain all the info that would be encoded in the DWARF linkage names). However, we don't attach `AsmLabel`s for structors because they have multiple variants and thus it's not clear which mangled name to use. In the [RFC on fixing expression evaluation of abi-tagged structors](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816) we discussed encoding the structor variant into the `AsmLabel`s. Specifically in [this thread](https://discourse.llvm.org/t/rfc-lldb-handling-abi-tagged-constructors-destructors-in-expression-evaluator/82816/7) we discussed that the contents of the `AsmLabel` are completely under LLDB's control and we could make use of it to uniquely identify a function by encoding the exact module and DIE that the function is associated with (mangled names need not be enough since two identical mangled symbols may live in different modules). So if we already have a custom `AsmLabel` format, we can encode the structor variant in a follow-up (the current idea is to append the structor variant as a suffix to our custom `AsmLabel` when Clang emits the mangled name into the JITted IR). Then we would just have to teach the `IRExecutionUnit` to pick the correct structor variant DIE during symbol resolution. The draft of this is available [here](llvm#149827) This patch sets up the infrastructure for the custom `AsmLabel` format by encoding the module id, DIE id and mangled name in it. **Implementation** The flow is as follows: 1. Create the label in `DWARFASTParserClang`. The format is: `$__lldb_func:module_id:die_id:mangled_name` 2. When resolving external symbols in `IRExecutionUnit`, we parse this label and then do a lookup by DIE ID (or mangled name into the module if the encoded DIE is a declaration). Depends on llvm#151355 (cherry picked from commit f890591)
This was added purely for the needs of LLDB. However, starting with llvm#151355 and llvm#148877 we no longer create literal AsmLabels in LLDB either. So this is unused and we can get rid of it. In the near future LLDB will want to add special support for mangling `AsmLabel`s (specifically llvm#149827). (cherry picked from commit cd8f348)
Split out from #148877
This patch prepares
TypeSystemClang
APIs to takeAsmLabel
s which concatenated strings (hencestd::string
) instead of a plainconst char*
.