[llvm] [DebugInfo] Support to get TU for hash from .debug_types.dwo section in DWARF4. (PR #161067)
Liu Ke via llvm-commits
llvm-commits at lists.llvm.org
Sun Sep 28 02:41:03 PDT 2025
https://github.com/Sockke created https://github.com/llvm/llvm-project/pull/161067
Using the DWP's cu_index/tu_index only loads the DWO units from the .debug_info.dwo section for hash, which works fine in DWARF5. However, tu_index points to .debug_types.dwo section in DWARF4, which can cause the type unit to be lost due to the incorrect loading target. (Related discussion in [811b60f](https://github.com/llvm/llvm-project/commit/811b60f0b99dad4b2989d21dde38d49155b0c4f9))
This patch supports to get the type unit for hash from .debug_types.dwo section in DWARF4.
>From a53da27bf27ff6299493917ce510ec7d6c8b21a9 Mon Sep 17 00:00:00 2001
From: "liuke.gehry" <liuke.gehry at bytedance.com>
Date: Fri, 26 Sep 2025 16:49:44 +0800
Subject: [PATCH] [DebugInfo] Support to get type units for hash from
.debug_types.dwo section in Dwarf4
---
llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h | 4 +++-
llvm/lib/DebugInfo/DWARF/DWARFContext.cpp | 19 ++++++++++++----
llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp | 22 +++++++++++++------
3 files changed, 33 insertions(+), 12 deletions(-)
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
index 964ff8e396660..3e8d7e8b32fc8 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFUnit.h
@@ -143,7 +143,9 @@ class DWARFUnitVector final : public SmallVector<std::unique_ptr<DWARFUnit>, 1>
decltype(make_filter_range(std::declval<iterator_range>(), isCompileUnit));
LLVM_ABI DWARFUnit *getUnitForOffset(uint64_t Offset) const;
- LLVM_ABI DWARFUnit *getUnitForIndexEntry(const DWARFUnitIndex::Entry &E);
+ LLVM_ABI DWARFUnit *
+ getUnitForIndexEntry(const DWARFUnitIndex::Entry &E, DWARFSectionKind Sec,
+ const DWARFSection *Section = nullptr);
/// Read units from a .debug_info or .debug_types section. Calls made
/// before finishedInfoUnits() are assumed to be for .debug_info sections,
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index 73df62abaf023..c40042c2958e4 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -1344,9 +1344,20 @@ void DWARFContext::dump(
DWARFTypeUnit *DWARFContext::getTypeUnitForHash(uint64_t Hash, bool IsDWO) {
DWARFUnitVector &DWOUnits = State->getDWOUnits();
if (const auto &TUI = getTUIndex()) {
- if (const auto *R = TUI.getFromHash(Hash))
- return dyn_cast_or_null<DWARFTypeUnit>(
- DWOUnits.getUnitForIndexEntry(*R));
+ if (const auto *R = TUI.getFromHash(Hash)) {
+ if (TUI.getVersion() >= 5)
+ return dyn_cast_or_null<DWARFTypeUnit>(
+ DWOUnits.getUnitForIndexEntry(*R, DW_SECT_INFO));
+ else {
+ DWARFUnit *TypesUnit = nullptr;
+ getDWARFObj().forEachTypesDWOSections([&](const DWARFSection &S) {
+ if (!TypesUnit)
+ TypesUnit =
+ DWOUnits.getUnitForIndexEntry(*R, DW_SECT_EXT_TYPES, &S);
+ });
+ return dyn_cast_or_null<DWARFTypeUnit>(TypesUnit);
+ }
+ }
return nullptr;
}
return State->getTypeUnitMap(IsDWO).lookup(Hash);
@@ -1358,7 +1369,7 @@ DWARFCompileUnit *DWARFContext::getDWOCompileUnitForHash(uint64_t Hash) {
if (const auto &CUI = getCUIndex()) {
if (const auto *R = CUI.getFromHash(Hash))
return dyn_cast_or_null<DWARFCompileUnit>(
- DWOUnits.getUnitForIndexEntry(*R));
+ DWOUnits.getUnitForIndexEntry(*R, DW_SECT_INFO));
return nullptr;
}
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
index ef59c82fc6a01..da0bf03e1ac57 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -161,17 +161,24 @@ DWARFUnit *DWARFUnitVector::getUnitForOffset(uint64_t Offset) const {
return nullptr;
}
-DWARFUnit *
-DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
- const auto *CUOff = E.getContribution(DW_SECT_INFO);
+DWARFUnit *DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E,
+ DWARFSectionKind Sec,
+ const DWARFSection *Section) {
+ const auto *CUOff = E.getContribution(Sec);
if (!CUOff)
return nullptr;
uint64_t Offset = CUOff->getOffset();
- auto end = begin() + getNumInfoUnits();
+ auto begin = this->begin();
+ auto end = begin + getNumInfoUnits();
+
+ if (Sec == DW_SECT_EXT_TYPES) {
+ begin = end;
+ end = this->end();
+ }
auto *CU =
- std::upper_bound(begin(), end, CUOff->getOffset(),
+ std::upper_bound(begin, end, CUOff->getOffset(),
[](uint64_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
return LHS < RHS->getNextUnitOffset();
});
@@ -181,13 +188,14 @@ DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
if (!Parser)
return nullptr;
- auto U = Parser(Offset, DW_SECT_INFO, nullptr, &E);
+ auto U = Parser(Offset, Sec, Section, &E);
if (!U)
return nullptr;
auto *NewCU = U.get();
this->insert(CU, std::move(U));
- ++NumInfoUnits;
+ if (Sec == DW_SECT_INFO)
+ ++NumInfoUnits;
return NewCU;
}
More information about the llvm-commits
mailing list