llvm-project/lldb/source/Core/Mangled.cpp

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

394 lines
13 KiB
C++
Raw Normal View History

//===-- Mangled.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/Core/Mangled.h"
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
#include "lldb/Core/RichManglingContext.h"
#include "lldb/Target/Language.h"
#include "lldb/Utility/ConstString.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/Logging.h"
#include "lldb/Utility/RegularExpression.h"
#include "lldb/Utility/Stream.h"
#include "lldb/lldb-enumerations.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Demangle/Demangle.h"
#include "llvm/Support/Compiler.h"
#include <mutex>
#include <string>
#include <utility>
#include <cstdlib>
#include <cstring>
using namespace lldb_private;
static inline bool cstring_is_mangled(llvm::StringRef s) {
return Mangled::GetManglingScheme(s) != Mangled::eManglingSchemeNone;
}
#pragma mark Mangled
Mangled::ManglingScheme Mangled::GetManglingScheme(llvm::StringRef const name) {
if (name.empty())
return Mangled::eManglingSchemeNone;
if (name.startswith("?"))
return Mangled::eManglingSchemeMSVC;
[lldb] Enable Rust v0 symbol demangling Rust's v0 name mangling scheme [1] is easy to disambiguate from other name mangling schemes because symbols always start with `_R`. The llvm Demangle library supports demangling the Rust v0 scheme. Use it to demangle Rust symbols. Added unit tests that check simple symbols. Ran LLDB built with this patch to debug some Rust programs compiled with the v0 name mangling scheme. Confirmed symbol names were demangled as expected. Note: enabling the new name mangling scheme requires a nightly toolchain: ``` $ cat main.rs fn main() { println!("Hello world!"); } $ $(rustup which --toolchain nightly rustc) -Z symbol-mangling-version=v0 main.rs -g $ /home/asm/hacking/llvm/build/bin/lldb ./main --one-line 'b main.rs:2' (lldb) target create "./main" Current executable set to '/home/asm/hacking/llvm/rust/main' (x86_64). (lldb) b main.rs:2 Breakpoint 1: where = main`main::main + 4 at main.rs:2:5, address = 0x00000000000076a4 (lldb) r Process 948449 launched: '/home/asm/hacking/llvm/rust/main' (x86_64) warning: (x86_64) /lib64/libgcc_s.so.1 No LZMA support found for reading .gnu_debugdata section Process 948449 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 1 fn main() { -> 2 println!("Hello world!"); 3 } (lldb) bt error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0 * thread #1, name = 'main', stop reason = breakpoint 1.1 * frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 frame #1: 0x000055555555b78b main`<fn() as core::ops::function::FnOnce<()>>::call_once((null)=(main`main::main at main.rs:1), (null)=<unavailable>) at function.rs:227:5 frame #2: 0x000055555555b66e main`std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>(f=(main`main::main at main.rs:1)) at backtrace.rs:125:18 frame #3: 0x000055555555b851 main`std::rt::lang_start::<()>::{closure#0} at rt.rs:49:18 frame #4: 0x000055555556c9f9 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] core::ops::function::impls::_$LT$impl$u20$core..ops..function..FnOnce$LT$A$GT$$u20$for$u20$$RF$F$GT$::call_once::h04259e4a34d07c2f at function.rs:259:13 frame #5: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::do_call::hb8da45704d5cfbbf at panicking.rs:401:40 frame #6: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::h4beadc19a78fec52 at panicking.rs:365:19 frame #7: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panic::catch_unwind::hc58016cd36ba81a4 at panic.rs:433:14 frame #8: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a at rt.rs:34:21 frame #9: 0x000055555555b830 main`std::rt::lang_start::<()>(main=(main`main::main at main.rs:1), argc=1, argv=0x00007fffffffcb18) at rt.rs:48:5 frame #10: 0x000055555555b6fc main`main + 28 frame #11: 0x00007ffff73f2493 libc.so.6`__libc_start_main + 243 frame #12: 0x000055555555b59e main`_start + 46 (lldb) ``` [1]: https://github.com/rust-lang/rust/issues/60705 Reviewed By: clayborg, teemperor Differential Revision: https://reviews.llvm.org/D104054
2021-06-21 23:56:55 +08:00
if (name.startswith("_R"))
return Mangled::eManglingSchemeRustV0;
if (name.startswith("_Z"))
return Mangled::eManglingSchemeItanium;
// ___Z is a clang extension of block invocations
if (name.startswith("___Z"))
return Mangled::eManglingSchemeItanium;
return Mangled::eManglingSchemeNone;
}
Mangled::Mangled(ConstString s) : m_mangled(), m_demangled() {
if (s)
SetValue(s);
}
Mangled::Mangled(llvm::StringRef name) {
if (!name.empty())
SetValue(ConstString(name));
}
// Convert to pointer operator. This allows code to check any Mangled objects
// to see if they contain anything valid using code such as:
//
// Mangled mangled(...);
// if (mangled)
// { ...
Mangled::operator void *() const {
return (m_mangled) ? const_cast<Mangled *>(this) : nullptr;
}
// Logical NOT operator. This allows code to check any Mangled objects to see
// if they are invalid using code such as:
//
// Mangled mangled(...);
// if (!file_spec)
// { ...
bool Mangled::operator!() const { return !m_mangled; }
// Clear the mangled and demangled values.
void Mangled::Clear() {
m_mangled.Clear();
m_demangled.Clear();
}
// Compare the string values.
int Mangled::Compare(const Mangled &a, const Mangled &b) {
return ConstString::Compare(a.GetName(ePreferMangled),
b.GetName(ePreferMangled));
}
// Set the string value in this objects. If "mangled" is true, then the mangled
// named is set with the new value in "s", else the demangled name is set.
void Mangled::SetValue(ConstString s, bool mangled) {
if (s) {
if (mangled) {
m_demangled.Clear();
m_mangled = s;
} else {
m_demangled = s;
m_mangled.Clear();
}
} else {
m_demangled.Clear();
m_mangled.Clear();
}
}
void Mangled::SetValue(ConstString name) {
if (name) {
if (cstring_is_mangled(name.GetStringRef())) {
m_demangled.Clear();
m_mangled = name;
} else {
m_demangled = name;
m_mangled.Clear();
}
} else {
m_demangled.Clear();
m_mangled.Clear();
}
}
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
// Local helpers for different demangling implementations.
static char *GetMSVCDemangledStr(const char *M) {
char *demangled_cstr = llvm::microsoftDemangle(
M, nullptr, nullptr, nullptr, nullptr,
llvm::MSDemangleFlags(
llvm::MSDF_NoAccessSpecifier | llvm::MSDF_NoCallingConvention |
llvm::MSDF_NoMemberType | llvm::MSDF_NoVariableType));
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
if (Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_DEMANGLE)) {
if (demangled_cstr && demangled_cstr[0])
LLDB_LOGF(log, "demangled msvc: %s -> \"%s\"", M, demangled_cstr);
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
else
LLDB_LOGF(log, "demangled msvc: %s -> error", M);
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
}
return demangled_cstr;
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
}
static char *GetItaniumDemangledStr(const char *M) {
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
char *demangled_cstr = nullptr;
llvm::ItaniumPartialDemangler ipd;
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
bool err = ipd.partialDemangle(M);
if (!err) {
// Default buffer and size (will realloc in case it's too small).
size_t demangled_size = 80;
demangled_cstr = static_cast<char *>(std::malloc(demangled_size));
demangled_cstr = ipd.finishDemangle(demangled_cstr, &demangled_size);
assert(demangled_cstr &&
"finishDemangle must always succeed if partialDemangle did");
assert(demangled_cstr[demangled_size - 1] == '\0' &&
"Expected demangled_size to return length including trailing null");
}
if (Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_DEMANGLE)) {
if (demangled_cstr)
LLDB_LOGF(log, "demangled itanium: %s -> \"%s\"", M, demangled_cstr);
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
else
LLDB_LOGF(log, "demangled itanium: %s -> error: failed to demangle", M);
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
}
return demangled_cstr;
}
[lldb] Enable Rust v0 symbol demangling Rust's v0 name mangling scheme [1] is easy to disambiguate from other name mangling schemes because symbols always start with `_R`. The llvm Demangle library supports demangling the Rust v0 scheme. Use it to demangle Rust symbols. Added unit tests that check simple symbols. Ran LLDB built with this patch to debug some Rust programs compiled with the v0 name mangling scheme. Confirmed symbol names were demangled as expected. Note: enabling the new name mangling scheme requires a nightly toolchain: ``` $ cat main.rs fn main() { println!("Hello world!"); } $ $(rustup which --toolchain nightly rustc) -Z symbol-mangling-version=v0 main.rs -g $ /home/asm/hacking/llvm/build/bin/lldb ./main --one-line 'b main.rs:2' (lldb) target create "./main" Current executable set to '/home/asm/hacking/llvm/rust/main' (x86_64). (lldb) b main.rs:2 Breakpoint 1: where = main`main::main + 4 at main.rs:2:5, address = 0x00000000000076a4 (lldb) r Process 948449 launched: '/home/asm/hacking/llvm/rust/main' (x86_64) warning: (x86_64) /lib64/libgcc_s.so.1 No LZMA support found for reading .gnu_debugdata section Process 948449 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 1 fn main() { -> 2 println!("Hello world!"); 3 } (lldb) bt error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0 * thread #1, name = 'main', stop reason = breakpoint 1.1 * frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 frame #1: 0x000055555555b78b main`<fn() as core::ops::function::FnOnce<()>>::call_once((null)=(main`main::main at main.rs:1), (null)=<unavailable>) at function.rs:227:5 frame #2: 0x000055555555b66e main`std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>(f=(main`main::main at main.rs:1)) at backtrace.rs:125:18 frame #3: 0x000055555555b851 main`std::rt::lang_start::<()>::{closure#0} at rt.rs:49:18 frame #4: 0x000055555556c9f9 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] core::ops::function::impls::_$LT$impl$u20$core..ops..function..FnOnce$LT$A$GT$$u20$for$u20$$RF$F$GT$::call_once::h04259e4a34d07c2f at function.rs:259:13 frame #5: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::do_call::hb8da45704d5cfbbf at panicking.rs:401:40 frame #6: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::h4beadc19a78fec52 at panicking.rs:365:19 frame #7: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panic::catch_unwind::hc58016cd36ba81a4 at panic.rs:433:14 frame #8: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a at rt.rs:34:21 frame #9: 0x000055555555b830 main`std::rt::lang_start::<()>(main=(main`main::main at main.rs:1), argc=1, argv=0x00007fffffffcb18) at rt.rs:48:5 frame #10: 0x000055555555b6fc main`main + 28 frame #11: 0x00007ffff73f2493 libc.so.6`__libc_start_main + 243 frame #12: 0x000055555555b59e main`_start + 46 (lldb) ``` [1]: https://github.com/rust-lang/rust/issues/60705 Reviewed By: clayborg, teemperor Differential Revision: https://reviews.llvm.org/D104054
2021-06-21 23:56:55 +08:00
static char *GetRustV0DemangledStr(const char *M) {
char *demangled_cstr = llvm::rustDemangle(M, nullptr, nullptr, nullptr);
if (Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_DEMANGLE)) {
if (demangled_cstr && demangled_cstr[0])
LLDB_LOG(log, "demangled rustv0: {0} -> \"{1}\"", M, demangled_cstr);
else
LLDB_LOG(log, "demangled rustv0: {0} -> error: failed to demangle", M);
}
return demangled_cstr;
}
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
// Explicit demangling for scheduled requests during batch processing. This
// makes use of ItaniumPartialDemangler's rich demangle info
bool Mangled::DemangleWithRichManglingInfo(
RichManglingContext &context, SkipMangledNameFn *skip_mangled_name) {
// Others are not meant to arrive here. ObjC names or C's main() for example
// have their names stored in m_demangled, while m_mangled is empty.
assert(m_mangled);
// Check whether or not we are interested in this name at all.
ManglingScheme scheme = GetManglingScheme(m_mangled.GetStringRef());
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
if (skip_mangled_name && skip_mangled_name(m_mangled.GetStringRef(), scheme))
return false;
switch (scheme) {
case eManglingSchemeNone:
// The current mangled_name_filter would allow llvm_unreachable here.
return false;
case eManglingSchemeItanium:
// We want the rich mangling info here, so we don't care whether or not
// there is a demangled string in the pool already.
if (context.FromItaniumName(m_mangled)) {
// If we got an info, we have a name. Copy to string pool and connect the
// counterparts to accelerate later access in GetDemangledName().
context.ParseFullName();
m_demangled.SetStringWithMangledCounterpart(context.GetBufferRef(),
m_mangled);
return true;
} else {
m_demangled.SetCString("");
return false;
}
case eManglingSchemeMSVC: {
// We have no rich mangling for MSVC-mangled names yet, so first try to
// demangle it if necessary.
if (!m_demangled && !m_mangled.GetMangledCounterpart(m_demangled)) {
if (char *d = GetMSVCDemangledStr(m_mangled.GetCString())) {
// If we got an info, we have a name. Copy to string pool and connect
// the counterparts to accelerate later access in GetDemangledName().
m_demangled.SetStringWithMangledCounterpart(llvm::StringRef(d),
m_mangled);
::free(d);
} else {
m_demangled.SetCString("");
}
}
if (m_demangled.IsEmpty()) {
// Cannot demangle it, so don't try parsing.
return false;
} else {
// Demangled successfully, we can try and parse it with
// CPlusPlusLanguage::MethodName.
return context.FromCxxMethodName(m_demangled);
}
}
[lldb] Enable Rust v0 symbol demangling Rust's v0 name mangling scheme [1] is easy to disambiguate from other name mangling schemes because symbols always start with `_R`. The llvm Demangle library supports demangling the Rust v0 scheme. Use it to demangle Rust symbols. Added unit tests that check simple symbols. Ran LLDB built with this patch to debug some Rust programs compiled with the v0 name mangling scheme. Confirmed symbol names were demangled as expected. Note: enabling the new name mangling scheme requires a nightly toolchain: ``` $ cat main.rs fn main() { println!("Hello world!"); } $ $(rustup which --toolchain nightly rustc) -Z symbol-mangling-version=v0 main.rs -g $ /home/asm/hacking/llvm/build/bin/lldb ./main --one-line 'b main.rs:2' (lldb) target create "./main" Current executable set to '/home/asm/hacking/llvm/rust/main' (x86_64). (lldb) b main.rs:2 Breakpoint 1: where = main`main::main + 4 at main.rs:2:5, address = 0x00000000000076a4 (lldb) r Process 948449 launched: '/home/asm/hacking/llvm/rust/main' (x86_64) warning: (x86_64) /lib64/libgcc_s.so.1 No LZMA support found for reading .gnu_debugdata section Process 948449 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 1 fn main() { -> 2 println!("Hello world!"); 3 } (lldb) bt error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0 * thread #1, name = 'main', stop reason = breakpoint 1.1 * frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 frame #1: 0x000055555555b78b main`<fn() as core::ops::function::FnOnce<()>>::call_once((null)=(main`main::main at main.rs:1), (null)=<unavailable>) at function.rs:227:5 frame #2: 0x000055555555b66e main`std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>(f=(main`main::main at main.rs:1)) at backtrace.rs:125:18 frame #3: 0x000055555555b851 main`std::rt::lang_start::<()>::{closure#0} at rt.rs:49:18 frame #4: 0x000055555556c9f9 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] core::ops::function::impls::_$LT$impl$u20$core..ops..function..FnOnce$LT$A$GT$$u20$for$u20$$RF$F$GT$::call_once::h04259e4a34d07c2f at function.rs:259:13 frame #5: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::do_call::hb8da45704d5cfbbf at panicking.rs:401:40 frame #6: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::h4beadc19a78fec52 at panicking.rs:365:19 frame #7: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panic::catch_unwind::hc58016cd36ba81a4 at panic.rs:433:14 frame #8: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a at rt.rs:34:21 frame #9: 0x000055555555b830 main`std::rt::lang_start::<()>(main=(main`main::main at main.rs:1), argc=1, argv=0x00007fffffffcb18) at rt.rs:48:5 frame #10: 0x000055555555b6fc main`main + 28 frame #11: 0x00007ffff73f2493 libc.so.6`__libc_start_main + 243 frame #12: 0x000055555555b59e main`_start + 46 (lldb) ``` [1]: https://github.com/rust-lang/rust/issues/60705 Reviewed By: clayborg, teemperor Differential Revision: https://reviews.llvm.org/D104054
2021-06-21 23:56:55 +08:00
case eManglingSchemeRustV0:
// Rich demangling scheme is not supported for Rust
return false;
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
}
llvm_unreachable("Fully covered switch above!");
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
}
// Generate the demangled name on demand using this accessor. Code in this
// class will need to use this accessor if it wishes to decode the demangled
// name. The result is cached and will be kept until a new string value is
// supplied to this object, or until the end of the object's lifetime.
ConstString Mangled::GetDemangledName() const {
// Check to make sure we have a valid mangled name and that we haven't
// already decoded our mangled name.
if (m_mangled && m_demangled.IsNull()) {
// Don't bother running anything that isn't mangled
const char *mangled_name = m_mangled.GetCString();
ManglingScheme mangling_scheme =
GetManglingScheme(m_mangled.GetStringRef());
if (mangling_scheme != eManglingSchemeNone &&
!m_mangled.GetMangledCounterpart(m_demangled)) {
// We didn't already mangle this name, demangle it and if all goes well
// add it to our map.
char *demangled_name = nullptr;
switch (mangling_scheme) {
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
case eManglingSchemeMSVC:
demangled_name = GetMSVCDemangledStr(mangled_name);
break;
case eManglingSchemeItanium: {
demangled_name = GetItaniumDemangledStr(mangled_name);
break;
}
[lldb] Enable Rust v0 symbol demangling Rust's v0 name mangling scheme [1] is easy to disambiguate from other name mangling schemes because symbols always start with `_R`. The llvm Demangle library supports demangling the Rust v0 scheme. Use it to demangle Rust symbols. Added unit tests that check simple symbols. Ran LLDB built with this patch to debug some Rust programs compiled with the v0 name mangling scheme. Confirmed symbol names were demangled as expected. Note: enabling the new name mangling scheme requires a nightly toolchain: ``` $ cat main.rs fn main() { println!("Hello world!"); } $ $(rustup which --toolchain nightly rustc) -Z symbol-mangling-version=v0 main.rs -g $ /home/asm/hacking/llvm/build/bin/lldb ./main --one-line 'b main.rs:2' (lldb) target create "./main" Current executable set to '/home/asm/hacking/llvm/rust/main' (x86_64). (lldb) b main.rs:2 Breakpoint 1: where = main`main::main + 4 at main.rs:2:5, address = 0x00000000000076a4 (lldb) r Process 948449 launched: '/home/asm/hacking/llvm/rust/main' (x86_64) warning: (x86_64) /lib64/libgcc_s.so.1 No LZMA support found for reading .gnu_debugdata section Process 948449 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 1 fn main() { -> 2 println!("Hello world!"); 3 } (lldb) bt error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0 * thread #1, name = 'main', stop reason = breakpoint 1.1 * frame #0: 0x000055555555b6a4 main`main::main at main.rs:2:5 frame #1: 0x000055555555b78b main`<fn() as core::ops::function::FnOnce<()>>::call_once((null)=(main`main::main at main.rs:1), (null)=<unavailable>) at function.rs:227:5 frame #2: 0x000055555555b66e main`std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>(f=(main`main::main at main.rs:1)) at backtrace.rs:125:18 frame #3: 0x000055555555b851 main`std::rt::lang_start::<()>::{closure#0} at rt.rs:49:18 frame #4: 0x000055555556c9f9 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] core::ops::function::impls::_$LT$impl$u20$core..ops..function..FnOnce$LT$A$GT$$u20$for$u20$$RF$F$GT$::call_once::h04259e4a34d07c2f at function.rs:259:13 frame #5: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::do_call::hb8da45704d5cfbbf at panicking.rs:401:40 frame #6: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panicking::try::h4beadc19a78fec52 at panicking.rs:365:19 frame #7: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a [inlined] std::panic::catch_unwind::hc58016cd36ba81a4 at panic.rs:433:14 frame #8: 0x000055555556c9f2 main`std::rt::lang_start_internal::hc51399759a90501a at rt.rs:34:21 frame #9: 0x000055555555b830 main`std::rt::lang_start::<()>(main=(main`main::main at main.rs:1), argc=1, argv=0x00007fffffffcb18) at rt.rs:48:5 frame #10: 0x000055555555b6fc main`main + 28 frame #11: 0x00007ffff73f2493 libc.so.6`__libc_start_main + 243 frame #12: 0x000055555555b59e main`_start + 46 (lldb) ``` [1]: https://github.com/rust-lang/rust/issues/60705 Reviewed By: clayborg, teemperor Differential Revision: https://reviews.llvm.org/D104054
2021-06-21 23:56:55 +08:00
case eManglingSchemeRustV0:
demangled_name = GetRustV0DemangledStr(mangled_name);
break;
case eManglingSchemeNone:
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
llvm_unreachable("eManglingSchemeNone was handled already");
}
if (demangled_name) {
Use rich mangling information in Symtab::InitNameIndexes() Summary: I set up a new review, because not all the code I touched was marked as a change in old one anymore. In preparation for this review, there were two earlier ones: * https://reviews.llvm.org/D49612 introduced the ItaniumPartialDemangler to LLDB demangling without conceptual changes * https://reviews.llvm.org/D49909 added a unit test that covers all relevant code paths in the InitNameIndexes() function Primary goals for this patch are: (1) Use ItaniumPartialDemangler's rich mangling info for building LLDB's name index. (2) Provide a uniform interface. (3) Improve indexing performance. The central implementation in this patch is our new function for explicit demangling: ``` const RichManglingInfo * Mangled::DemangleWithRichManglingInfo(RichManglingContext &, SkipMangledNameFn *) ``` It takes a context object and a filter function and provides read-only access to the rich mangling info on success, or otherwise returns null. The two new classes are: * `RichManglingInfo` offers a uniform interface to query symbol properties like `getFunctionDeclContextName()` or `isCtorOrDtor()` that are forwarded to the respective provider internally (`llvm::ItaniumPartialDemangler` or `lldb_private::CPlusPlusLanguage::MethodName`). * `RichManglingContext` works a bit like `LLVMContext`, it the actual `RichManglingInfo` returned from `DemangleWithRichManglingInfo()` and handles lifetime and configuration. It is likely stack-allocated and can be reused for multiple queries during batch processing. The idea here is that `DemangleWithRichManglingInfo()` acts like a gate keeper. It only provides access to `RichManglingInfo` on success, which in turn avoids the need to handle a `NoInfo` state in every single one of its getters. Having it stored within the context, avoids extra heap allocations and aids (3). As instantiations of the IPD the are considered expensive, the context is the ideal place to store it too. An efficient filtering function `SkipMangledNameFn` is another piece in the performance puzzle and it helps to mimic the original behavior of `InitNameIndexes`. Future potential: * `DemangleWithRichManglingInfo()` is thread-safe, IFF using different contexts in different threads. This may be exploited in the future. (It's another thing that it has in common with `LLVMContext`.) * The old implementation only parsed and indexed Itanium mangled names. The new `RichManglingInfo` can be extended for various mangling schemes and languages. One problem with the implementation of RichManglingInfo is the inaccessibility of class `CPlusPlusLanguage::MethodName` (defined in source/Plugins/Language/..), from within any header in the Core components of LLDB. The rather hacky solution is to store a type erased reference and cast it to the correct type on access in the cpp - see `RichManglingInfo::get<ParserT>()`. At the moment there seems to be no better way to do it. IMHO `CPlusPlusLanguage::MethodName` should be a top-level class in order to enable forward delcarations (but that is a rather big change I guess). First simple profiling shows a good speedup. `target create clang` now takes 0.64s on average. Before the change I observed runtimes between 0.76s an 1.01s. This is still no bulletproof data (I only ran it on one machine!), but it's a promising indicator I think. Reviewers: labath, jingham, JDevlieghere, erik.pilkington Subscribers: zturner, clayborg, mgorny, lldb-commits Differential Revision: https://reviews.llvm.org/D50071 llvm-svn: 339291
2018-08-09 05:57:37 +08:00
m_demangled.SetStringWithMangledCounterpart(
llvm::StringRef(demangled_name), m_mangled);
free(demangled_name);
}
}
if (m_demangled.IsNull()) {
// Set the demangled string to the empty string to indicate we tried to
// parse it once and failed.
m_demangled.SetCString("");
}
}
return m_demangled;
}
ConstString Mangled::GetDisplayDemangledName() const {
return GetDemangledName();
}
bool Mangled::NameMatches(const RegularExpression &regex) const {
if (m_mangled && regex.Execute(m_mangled.GetStringRef()))
return true;
ConstString demangled = GetDemangledName();
return demangled && regex.Execute(demangled.GetStringRef());
}
// Get the demangled name if there is one, else return the mangled name.
ConstString Mangled::GetName(Mangled::NamePreference preference) const {
if (preference == ePreferMangled && m_mangled)
return m_mangled;
// Call the accessor to make sure we get a demangled name in case it hasn't
// been demangled yet...
ConstString demangled = GetDemangledName();
if (preference == ePreferDemangledWithoutArguments) {
if (Language *lang = Language::FindPlugin(GuessLanguage())) {
return lang->GetDemangledFunctionNameWithoutArguments(*this);
}
}
if (preference == ePreferDemangled) {
if (demangled)
return demangled;
return m_mangled;
}
return demangled;
}
// Dump a Mangled object to stream "s". We don't force our demangled name to be
// computed currently (we don't use the accessor).
void Mangled::Dump(Stream *s) const {
if (m_mangled) {
*s << ", mangled = " << m_mangled;
}
if (m_demangled) {
const char *demangled = m_demangled.AsCString();
s->Printf(", demangled = %s", demangled[0] ? demangled : "<error>");
}
}
// Dumps a debug version of this string with extra object and state information
// to stream "s".
void Mangled::DumpDebug(Stream *s) const {
s->Printf("%*p: Mangled mangled = ", static_cast<int>(sizeof(void *) * 2),
static_cast<const void *>(this));
m_mangled.DumpDebug(s);
s->Printf(", demangled = ");
m_demangled.DumpDebug(s);
}
// Return the size in byte that this object takes in memory. The size includes
// the size of the objects it owns, and not the strings that it references
// because they are shared strings.
size_t Mangled::MemorySize() const {
return m_mangled.MemorySize() + m_demangled.MemorySize();
}
// We "guess" the language because we can't determine a symbol's language from
// it's name. For example, a Pascal symbol can be mangled using the C++
// Itanium scheme, and defined in a compilation unit within the same module as
// other C++ units. In addition, different targets could have different ways
// of mangling names from a given language, likewise the compilation units
// within those targets.
lldb::LanguageType Mangled::GuessLanguage() const {
lldb::LanguageType result = lldb::eLanguageTypeUnknown;
// Ask each language plugin to check if the mangled name belongs to it.
Language::ForEach([this, &result](Language *l) {
if (l->SymbolNameFitsToLanguage(*this)) {
result = l->GetLanguageType();
return false;
}
return true;
});
return result;
}
// Dump OBJ to the supplied stream S.
Stream &operator<<(Stream &s, const Mangled &obj) {
if (obj.GetMangledName())
s << "mangled = '" << obj.GetMangledName() << "'";
ConstString demangled = obj.GetDemangledName();
if (demangled)
s << ", demangled = '" << demangled << '\'';
else
s << ", demangled = <error>";
return s;
}