[clang] [llvm] [DLCov 4/5] Track coverage and origins through IRBuilder (PR #108214)
via cfe-commits
cfe-commits at lists.llvm.org
Wed Sep 11 05:52:18 PDT 2024
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-debuginfo
Author: Stephen Tozer (SLTozer)
<details>
<summary>Changes</summary>
This is part of a series of patches that tries to improve DILocation bug detection in Debugify; see below for more details. This patch modifies the IRBuilder to pass coverage and origin data through the IRBuilder, tracking the initial DebugLoc set in the IRBuilder (via `setCurrentDebugLocation`) as well as the point where we attach that DebugLoc to an inserted instruction. An important part of this patch is that it stores a DebugLoc directly in the IRBuilder instead of storing a DILocation metadata, meaning that coverage information is propagated through it. It also means that in the resulting Debugify report, we see two origin stack traces for the bug: that of the original DebugLoc, and the stack trace where we set this for the newly inserted instruction. The usefulness of this is that for any given bug, either of these could be relevant; the error could result from bad DebugLocs on existing instructions being propagated, in which case the original DebugLoc is what we care about, or it could result from the IRBuilder not having the correct DebugLoc set for it.
There are few places in the compiler where this sort of extension is necessary - the IRBuilder is a specific case where we propagate DebugLocs between instructions in an indirect way, using DILocation internally, which is used frequently enough for this modification to be worthwhile. The only other cases I've seen so far, which will be covered in the next patch, are the functions for merging DILocations.
--------------------
This series of patches adds a "DebugLoc coverage tracking" feature, that inserts conditionally-compiled tracking information into DebugLocs (and by extension, to Instructions), which is used by Debugify to provide more accurate and detailed coverage reports. When enabled, this features tracks whether and why we have intentionally dropped a DebugLoc, allowing Debugify to ignore false positives. An optional additional feature allows also storing a stack trace of the point where a DebugLoc was unintentionally dropped/not generated, which is used to make fixing detected errors significantly easier. The goal of these features is to provide useful tools for developers to fix existing DebugLoc errors and allow reliable detection of regressions by either manual inspection or an automated script.
Previous: https://github.com/llvm/llvm-project/pull/107369
---
Patch is 39.63 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/108214.diff
20 Files Affected:
- (modified) clang/lib/CodeGen/BackendUtil.cpp (+16)
- (modified) llvm/CMakeLists.txt (+4)
- (modified) llvm/cmake/modules/HandleLLVMOptions.cmake (+13)
- (modified) llvm/docs/CMake.rst (+11)
- (modified) llvm/include/llvm/Config/config.h.cmake (+8)
- (modified) llvm/include/llvm/IR/DebugLoc.h (+113-1)
- (modified) llvm/include/llvm/IR/IRBuilder.h (+27-4)
- (modified) llvm/include/llvm/Support/Signals.h (+40)
- (modified) llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (+5)
- (modified) llvm/lib/CodeGen/BranchFolding.cpp (+1-1)
- (modified) llvm/lib/CodeGen/BranchFolding.h (+8-4)
- (modified) llvm/lib/IR/DebugInfo.cpp (+2-2)
- (modified) llvm/lib/IR/DebugLoc.cpp (+36)
- (modified) llvm/lib/IR/IRBuilder.cpp (+6-12)
- (modified) llvm/lib/IR/Instruction.cpp (+4-2)
- (modified) llvm/lib/Support/Signals.cpp (+116)
- (modified) llvm/lib/Support/Unix/Signals.inc (+15)
- (modified) llvm/lib/Support/Windows/Signals.inc (+5)
- (modified) llvm/lib/Transforms/Utils/Debugify.cpp (+79-17)
- (modified) llvm/utils/llvm-original-di-preservation.py (+13-9)
``````````diff
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index e765bbf637a661..20653daff7d4ae 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -911,6 +911,22 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
Debugify.setOrigDIVerifyBugsReportFilePath(
CodeGenOpts.DIBugsReportFilePath);
Debugify.registerCallbacks(PIC, MAM);
+
+#if ENABLE_DEBUGLOC_COVERAGE_TRACKING
+ // If we're using debug location coverage tracking, mark all the
+ // instructions coming out of the frontend without a DebugLoc as being
+ // intentional line-zero locations, to prevent both those instructions and
+ // new instructions that inherit their location from being treated as
+ // incorrectly empty locations.
+ for (Function &F : *TheModule) {
+ if (!F.getSubprogram())
+ continue;
+ for (BasicBlock &BB : F)
+ for (Instruction &I : BB)
+ if (!I.getDebugLoc())
+ I.setDebugLoc(DebugLoc::getLineZero());
+ }
+#endif
}
// Attempt to load pass plugins and register their callbacks with PB.
for (auto &PluginFN : CodeGenOpts.PassPlugins) {
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index 12618966c4adfd..3e2e90f5adad2e 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -524,6 +524,10 @@ endif()
option(LLVM_ENABLE_CRASH_DUMPS "Turn on memory dumps on crashes. Currently only implemented on Windows." OFF)
+set(LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING "DISABLED" CACHE STRING
+ "Enhance debugify's line number coverage tracking; enabling this is abi-breaking. Can be DISABLED, COVERAGE, or COVERAGE_AND_ORIGIN.")
+set_property(CACHE LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING PROPERTY STRINGS DISABLED COVERAGE COVERAGE_AND_ORIGIN)
+
set(WINDOWS_PREFER_FORWARD_SLASH_DEFAULT OFF)
if (MINGW)
# Cygwin doesn't identify itself as Windows, and thus gets path::Style::posix
diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
index 5ca580fbb59c59..7f66e55dca13b1 100644
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -196,6 +196,19 @@ else()
message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!")
endif()
+string(TOUPPER "${LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING}" uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING)
+
+if( uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING STREQUAL "COVERAGE" )
+ set( ENABLE_DEBUGLOC_COVERAGE_TRACKING 1 )
+elseif( uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING STREQUAL "COVERAGE_AND_ORIGIN" )
+ set( ENABLE_DEBUGLOC_COVERAGE_TRACKING 1 )
+ set( ENABLE_DEBUGLOC_ORIGIN_TRACKING 1 )
+elseif( uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING STREQUAL "DISABLED" OR NOT DEFINED LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING )
+ # The DISABLED setting is default and requires no additional defines.
+else()
+ message(FATAL_ERROR "Unknown value for LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING: \"${LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING}\"!")
+endif()
+
if( LLVM_REVERSE_ITERATION )
set( LLVM_ENABLE_REVERSE_ITERATION 1 )
endif()
diff --git a/llvm/docs/CMake.rst b/llvm/docs/CMake.rst
index 2a80813999ea1e..304e22759770d9 100644
--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@@ -475,6 +475,17 @@ enabled sub-projects. Nearly all of these variable names begin with
**LLVM_ENABLE_BINDINGS**:BOOL
If disabled, do not try to build the OCaml bindings.
+**LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING**:STRING
+ Enhances Debugify's ability to detect line number errors by storing extra
+ information inside Instructions, removing false positives from Debugify's
+ results at the cost of performance. Allowed values are `DISABLED` (default),
+ `COVERAGE`, and `COVERAGE_AND_ORIGIN`. `COVERAGE` tracks whether and why a
+ line number was intentionally dropped or not generated for an instruction,
+ allowing Debugify to avoid reporting these as errors. `COVERAGE_AND_ORIGIN`
+ additionally stores a stacktrace of the point where each DebugLoc is
+ unintentionally dropped, allowing for much easier bug triaging at the cost of
+ a ~10x performance slowdown.
+
**LLVM_ENABLE_DIA_SDK**:BOOL
Enable building with MSVC DIA SDK for PDB debugging support. Available
only with MSVC. Defaults to ON.
diff --git a/llvm/include/llvm/Config/config.h.cmake b/llvm/include/llvm/Config/config.h.cmake
index ff30741c8f360a..7e8f1aa9474654 100644
--- a/llvm/include/llvm/Config/config.h.cmake
+++ b/llvm/include/llvm/Config/config.h.cmake
@@ -19,6 +19,14 @@
/* Define to 1 to enable crash memory dumps, and to 0 otherwise. */
#cmakedefine01 LLVM_ENABLE_CRASH_DUMPS
+/* Define to 1 to enable expensive checks for debug location coverage checking,
+ and to 0 otherwise. */
+#cmakedefine01 ENABLE_DEBUGLOC_COVERAGE_TRACKING
+
+/* Define to 1 to enable expensive tracking of the origin of debug location
+ coverage bugs, and to 0 otherwise. */
+#cmakedefine01 ENABLE_DEBUGLOC_ORIGIN_TRACKING
+
/* Define to 1 to prefer forward slashes on Windows, and to 0 prefer
backslashes. */
#cmakedefine01 LLVM_WINDOWS_PREFER_FORWARD_SLASH
diff --git a/llvm/include/llvm/IR/DebugLoc.h b/llvm/include/llvm/IR/DebugLoc.h
index c22d3e9b10d27f..a3e26eadb224d4 100644
--- a/llvm/include/llvm/IR/DebugLoc.h
+++ b/llvm/include/llvm/IR/DebugLoc.h
@@ -14,6 +14,7 @@
#ifndef LLVM_IR_DEBUGLOC_H
#define LLVM_IR_DEBUGLOC_H
+#include "llvm/Config/config.h"
#include "llvm/IR/TrackingMDRef.h"
#include "llvm/Support/DataTypes.h"
@@ -22,6 +23,90 @@ namespace llvm {
class LLVMContext;
class raw_ostream;
class DILocation;
+ class Function;
+
+#if ENABLE_DEBUGLOC_COVERAGE_TRACKING
+#if ENABLE_DEBUGLOC_ORIGIN_TRACKING
+ struct DbgLocOrigin {
+ static constexpr unsigned long MaxDepth = 16;
+ using StackTracesTy =
+ SmallVector<std::pair<int, std::array<void *, MaxDepth>>, 0>;
+ StackTracesTy StackTraces;
+ DbgLocOrigin(bool ShouldCollectTrace);
+ void addTrace();
+ const StackTracesTy &getOriginStackTraces() const { return StackTraces; };
+ };
+#else
+ struct DbgLocOrigin {
+ DbgLocOrigin(bool) {}
+ };
+#endif
+
+ // Used to represent different "kinds" of DebugLoc, expressing that a DebugLoc
+ // is either ordinary, containing a valid DILocation, or otherwise describing
+ // the reason why the DebugLoc does not contain a valid DILocation.
+ enum class DebugLocKind : uint8_t {
+ // DebugLoc is expected to contain a valid DILocation.
+ Normal,
+ // DebugLoc intentionally does not have a valid DILocation; may be for a
+ // compiler-generated instruction, or an explicitly dropped location.
+ LineZero,
+ // DebugLoc does not have a known or currently knowable source location,
+ // e.g. the attribution is ambiguous in a way that can't be represented, or
+ // determining the correct location is complicated and requires future
+ // developer effort.
+ Unknown,
+ // DebugLoc is attached to an instruction that we don't expect to be
+ // emitted, and so can omit a valid DILocation; we don't expect to ever try
+ // and emit these into the line table, and trying to do so is a sign that
+ // something has gone wrong (most likely a DebugLoc leaking from a transient
+ // compiler-generated instruction).
+ Temporary
+ };
+
+ // Extends TrackingMDNodeRef to also store a DebugLocKind and Origin,
+ // allowing Debugify to ignore intentionally-empty DebugLocs and display the
+ // code responsible for generating unintentionally-empty DebugLocs.
+ // Currently we only need to track the Origin of this DILoc when using a
+ // DebugLoc that is Normal and empty, so only collect the origin stacktrace in
+ // those cases.
+ class DILocAndCoverageTracking : public TrackingMDNodeRef,
+ public DbgLocOrigin {
+ public:
+ DebugLocKind Kind;
+ // Default constructor for empty DebugLocs.
+ DILocAndCoverageTracking()
+ : TrackingMDNodeRef(nullptr), DbgLocOrigin(true),
+ Kind(DebugLocKind::Normal) {}
+ // Valid or nullptr MDNode*, normal DebugLocKind
+ DILocAndCoverageTracking(const MDNode *Loc)
+ : TrackingMDNodeRef(const_cast<MDNode *>(Loc)), DbgLocOrigin(!Loc),
+ Kind(DebugLocKind::Normal) {}
+ DILocAndCoverageTracking(const DILocation *Loc);
+ // Always nullptr MDNode*, any DebugLocKind
+ DILocAndCoverageTracking(DebugLocKind Kind)
+ : TrackingMDNodeRef(nullptr),
+ DbgLocOrigin(Kind == DebugLocKind::Normal), Kind(Kind) {}
+ };
+ template <> struct simplify_type<DILocAndCoverageTracking> {
+ using SimpleType = MDNode *;
+
+ static MDNode *getSimplifiedValue(DILocAndCoverageTracking &MD) {
+ return MD.get();
+ }
+ };
+ template <> struct simplify_type<const DILocAndCoverageTracking> {
+ using SimpleType = MDNode *;
+
+ static MDNode *getSimplifiedValue(const DILocAndCoverageTracking &MD) {
+ return MD.get();
+ }
+ };
+
+ using DebugLocTrackingRef = DILocAndCoverageTracking;
+#else
+ using DebugLocTrackingRef = TrackingMDNodeRef;
+#endif // ENABLE_DEBUGLOC_COVERAGE_TRACKING
/// A debug info location.
///
@@ -31,7 +116,8 @@ namespace llvm {
/// To avoid extra includes, \a DebugLoc doubles the \a DILocation API with a
/// one based on relatively opaque \a MDNode pointers.
class DebugLoc {
- TrackingMDNodeRef Loc;
+
+ DebugLocTrackingRef Loc;
public:
DebugLoc() = default;
@@ -47,6 +133,32 @@ namespace llvm {
/// IR.
explicit DebugLoc(const MDNode *N);
+#if ENABLE_DEBUGLOC_COVERAGE_TRACKING
+ DebugLoc(DebugLocKind Kind) : Loc(Kind) {}
+ DebugLocKind getKind() const { return Loc.Kind; }
+#endif
+
+#if ENABLE_DEBUGLOC_ORIGIN_TRACKING
+#if !ENABLE_DEBUGLOC_COVERAGE_TRACKING
+#error Cannot enable DebugLoc origin-tracking without coverage-tracking!
+#endif
+
+ const DbgLocOrigin::StackTracesTy &getOriginStackTraces() const {
+ return Loc.getOriginStackTraces();
+ }
+ DebugLoc getCopied() const {
+ DebugLoc NewDL = *this;
+ NewDL.Loc.addTrace();
+ return NewDL;
+ }
+#else
+ DebugLoc getCopied() const { return *this; }
+#endif
+
+ static DebugLoc getTemporary();
+ static DebugLoc getUnknown();
+ static DebugLoc getLineZero();
+
/// Get the underlying \a DILocation.
///
/// \pre !*this or \c isa<DILocation>(getAsMDNode()).
diff --git a/llvm/include/llvm/IR/IRBuilder.h b/llvm/include/llvm/IR/IRBuilder.h
index 31a1fef3219950..884fb9a6be941d 100644
--- a/llvm/include/llvm/IR/IRBuilder.h
+++ b/llvm/include/llvm/IR/IRBuilder.h
@@ -90,12 +90,23 @@ class IRBuilderCallbackInserter : public IRBuilderDefaultInserter {
/// Common base class shared among various IRBuilders.
class IRBuilderBase {
/// Pairs of (metadata kind, MDNode *) that should be added to all newly
- /// created instructions, like !dbg metadata.
+ /// created instructions, excluding !dbg metadata, which is stored in the
+ // StoredDL field.
SmallVector<std::pair<unsigned, MDNode *>, 2> MetadataToCopy;
+ // The DebugLoc that will be applied to instructions inserted by this builder.
+ DebugLoc StoredDL;
+ // Tracks whether we have explicitly set a DebugLoc - valid or empty - in this
+ // builder, to determine whether to copy StoredDL to inserted instructions.
+ // We use this bool instead of an optional because we may stil want to copy
+ // the default (empty) StoredDL to some instructions.
+ bool HasExplicitDL = false;
/// Add or update the an entry (Kind, MD) to MetadataToCopy, if \p MD is not
/// null. If \p MD is null, remove the entry with \p Kind.
void AddOrRemoveMetadataToCopy(unsigned Kind, MDNode *MD) {
+ assert(Kind != LLVMContext::MD_dbg &&
+ "MD_dbg metadata must be stored in StoredDL");
+
if (!MD) {
erase_if(MetadataToCopy, [Kind](const std::pair<unsigned, MDNode *> &KV) {
return KV.first == Kind;
@@ -215,7 +226,10 @@ class IRBuilderBase {
/// Set location information used by debugging information.
void SetCurrentDebugLocation(DebugLoc L) {
- AddOrRemoveMetadataToCopy(LLVMContext::MD_dbg, L.getAsMDNode());
+ // For !dbg metadata attachments, we use DebugLoc instead of the raw MDNode
+ // to include optional introspection data for use in Debugify.
+ StoredDL = std::move(L);
+ HasExplicitDL = true;
}
/// Set nosanitize metadata.
@@ -229,8 +243,12 @@ class IRBuilderBase {
/// not on \p Src will be dropped from MetadataToCopy.
void CollectMetadataToCopy(Instruction *Src,
ArrayRef<unsigned> MetadataKinds) {
- for (unsigned K : MetadataKinds)
- AddOrRemoveMetadataToCopy(K, Src->getMetadata(K));
+ for (unsigned K : MetadataKinds) {
+ if (K == LLVMContext::MD_dbg)
+ SetCurrentDebugLocation(Src->getDebugLoc());
+ else
+ AddOrRemoveMetadataToCopy(K, Src->getMetadata(K));
+ }
}
/// Get location information used by debugging information.
@@ -244,6 +262,11 @@ class IRBuilderBase {
void AddMetadataToInst(Instruction *I) const {
for (const auto &KV : MetadataToCopy)
I->setMetadata(KV.first, KV.second);
+ // If I does not have an existing DebugLoc and no DebugLoc has been set
+ // here, we copy our DebugLoc to I anyway, because more likely than not I
+ // is a new instruction whose DL should originate from this builder.
+ if (HasExplicitDL || !I->getDebugLoc())
+ I->setDebugLoc(StoredDL.getCopied());
}
/// Get the return type of the current function that we're emitting
diff --git a/llvm/include/llvm/Support/Signals.h b/llvm/include/llvm/Support/Signals.h
index 70749ce30184a7..6addb8212e20ac 100644
--- a/llvm/include/llvm/Support/Signals.h
+++ b/llvm/include/llvm/Support/Signals.h
@@ -14,6 +14,8 @@
#ifndef LLVM_SUPPORT_SIGNALS_H
#define LLVM_SUPPORT_SIGNALS_H
+#include "llvm/Config/config.h"
+#include <array>
#include <cstdint>
#include <string>
@@ -21,6 +23,22 @@ namespace llvm {
class StringRef;
class raw_ostream;
+#if ENABLE_DEBUGLOC_ORIGIN_TRACKING
+// Typedefs that are convenient but only used by the StackTrace-collection code
+// added if DebugLoc origin-tracking is enabled.
+template <typename T, typename Enable> struct DenseMapInfo;
+template <typename ValueT, typename ValueInfoT> class DenseSet;
+namespace detail {
+template <typename KeyT, typename ValueT> struct DenseMapPair;
+}
+template <typename KeyT, typename ValueT, typename KeyInfoT, typename BucketT>
+class DenseMap;
+using AddressSet = DenseSet<void *, DenseMapInfo<void *, void>>;
+using SymbolizedAddressMap =
+ DenseMap<void *, std::string, DenseMapInfo<void *, void>,
+ detail::DenseMapPair<void *, std::string>>;
+#endif
+
namespace sys {
/// This function runs all the registered interrupt handlers, including the
@@ -55,6 +73,28 @@ namespace sys {
/// specified, the entire frame is printed.
void PrintStackTrace(raw_ostream &OS, int Depth = 0);
+#if ENABLE_DEBUGLOC_ORIGIN_TRACKING
+#ifdef NDEBUG
+#error DebugLoc origin-tracking should not be enabled in Release builds.
+#endif
+ /// Populates the given array with a stacktrace of the current program, up to
+ /// MaxDepth frames. Returns the number of frames returned, which will be
+ /// inserted into \p StackTrace from index 0. All entries after the returned
+ /// depth will be unmodified. NB: This is only intended to be used for
+ /// introspection of LLVM by Debugify, will not be enabled in release builds,
+ /// and should not be relied on for other purposes.
+ template <unsigned long MaxDepth>
+ int getStackTrace(std::array<void *, MaxDepth> &StackTrace);
+
+ /// Takes a set of \p Addresses, symbolizes them and stores the result in the
+ /// provided \p SymbolizedAddresses map.
+ /// NB: This is only intended to be used for introspection of LLVM by
+ /// Debugify, will not be enabled in release builds, and should not be relied
+ /// on for other purposes.
+ void symbolizeAddresses(AddressSet &Addresses,
+ SymbolizedAddressMap &SymbolizedAddresses);
+#endif
+
// Run all registered signal handlers.
void RunSignalHandlers();
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index f88653146cc6ff..4ba8262259b112 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -31,6 +31,7 @@
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/Config/config.h"
#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
#include "llvm/IR/Constants.h"
@@ -2080,6 +2081,10 @@ void DwarfDebug::beginInstruction(const MachineInstr *MI) {
}
if (!DL) {
+ // FIXME: We could assert that `DL.getKind() != DebugLocKind::Temporary`
+ // here, or otherwise record any temporary DebugLocs seen to ensure that
+ // transient compiler-generated instructions aren't leaking their DLs to
+ // other instructions.
// We have an unspecified location, which might want to be line 0.
// If we have already emitted a line-0 record, don't repeat it.
if (LastAsmLine == 0)
diff --git a/llvm/lib/CodeGen/BranchFolding.cpp b/llvm/lib/CodeGen/BranchFolding.cpp
index 92a03eb52e35d9..edd60c5ad4a18d 100644
--- a/llvm/lib/CodeGen/BranchFolding.cpp
+++ b/llvm/lib/CodeGen/BranchFolding.cpp
@@ -915,7 +915,7 @@ bool BranchFolder::TryTailMergeBlocks(MachineBasicBlock *SuccBB,
// Walk through equivalence sets looking for actual exact matches.
while (MergePotentials.size() > 1) {
unsigned CurHash = MergePotentials.back().getHash();
- const DebugLoc &BranchDL = MergePotentials.back().getBranchDebugLoc();
+ const DebugLoc BranchDL = MergePotentials.back().getBranchDebugLoc();
// Build SameTails, identifying the set of blocks with this hash code
// and with the maximum number of instructions in common.
diff --git a/llvm/lib/CodeGen/BranchFolding.h b/llvm/lib/CodeGen/BranchFolding.h
index ff2bbe06c04887..9638cfda1239d1 100644
--- a/llvm/lib/CodeGen/BranchFolding.h
+++ b/llvm/lib/CodeGen/BranchFolding.h
@@ -50,11 +50,15 @@ class TargetRegisterInfo;
class MergePotentialsElt {
unsigned Hash;
MachineBasicBlock *Block;
- DebugLoc BranchDebugLoc;
+ // We use MDNode rather than DebugLoc here because under certain CMake
+ // options*, DebugLoc may contain a SmallVector used for introspection
+ // purposes, which causes errors when stored here.
+ // *LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING=COVERAGE_AND_ORIGIN
+ MDNode *BranchDebugLoc;
public:
- MergePotentialsElt(unsigned h, MachineBasicBlock *b, DebugLoc bdl)
- : Hash(h), Block(b), BranchDebugLoc(std::move(bdl)) {}
+ MergePotentialsElt(unsigned h, MachineBasicBlock *b, MDNode *bdl)
+ : Hash(h), Block(b), BranchDebugLoc(bdl) {}
unsigned getHash() const { return Hash; }
MachineBasicBlock *getBlock() const { return Block; }
@@ -63,7 +67,7 @@ class TargetRegisterInfo;
Block = MBB;
}
- const DebugLoc &getBranchDebugLoc() { return BranchDebugLoc; }
+ const DebugLoc getBranchDebugLoc() { return DebugLoc(BranchDebugLoc); }
bool operator<(const MergePotentialsElt &) const;
};
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 7fa1f9696d43b2..86ac46540c5ef9 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -979,7 +979,7 @@ void Instruction::dropLocation() {
}
if (!MayLowerToCall) {
- setDebugLoc(DebugLoc());
+ setDebugLoc(DebugLoc::getLineZero());
return;
}
@@ -998,7 +998,7 @@ void Instruction::dropLocation() {
//
// One alternative is to set a line 0 location with the existing scope and
// inlinedAt info. The location might be sensitive to when inlining occurs.
- setDebugLoc(DebugLoc());
+ setDebugLoc(DebugLoc::getLineZero());
}
//===----------------------------------------------------------------------===//
diff --git a/llvm/lib/IR/DebugLoc.cpp b/llvm/lib/IR/DebugLoc.cpp
index bdea52180f74ae..ad02cd078df043 100644
--- a/llvm/lib/IR/DebugLoc.cpp
+++ b/llvm/lib/IR/DebugLoc.cpp
@@ -9,8 +9,44 @@
#include "llvm/IR/DebugLoc.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/IR/...
[truncated]
``````````
</details>
https://github.com/llvm/llvm-project/pull/108214
More information about the cfe-commits
mailing list