Merge ArtificialLocation into ApplyDebugLocation and make a clear
distinction between the different use-cases. With the previous default
behavior we would occasionally emit empty debug locations in situations
where they actually were strictly required (= on invoke insns).
We now have a choice between defaulting to an empty location or an
artificial location.
Specifically, this fixes a bug caused by a missing debug location when
emitting C++ EH cleanup blocks from within an artificial function, such as
an ObjC destroy helper function.
rdar://problem/19670595
llvm-svn: 228003
diff --git a/clang/lib/CodeGen/CGBlocks.cpp b/clang/lib/CodeGen/CGBlocks.cpp
index b98460a..ffc6e57 100644
--- a/clang/lib/CodeGen/CGBlocks.cpp
+++ b/clang/lib/CodeGen/CGBlocks.cpp
@@ -1178,7 +1178,7 @@
Alloca->setAlignment(Align);
// Set the DebugLocation to empty, so the store is recognized as a
// frame setup instruction by llvm::DwarfDebug::beginFunction().
- ApplyDebugLocation NL(*this);
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::MarkAsPrologue);
Builder.CreateAlignedStore(BlockPointer, Alloca, Align);
BlockPointerDbgLoc = Alloca;
}
@@ -1328,10 +1328,10 @@
nullptr, SC_Static,
false,
false);
- // Create a scope with an artificial location for the body of this function.
- ApplyDebugLocation NL(*this);
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::MarkAsPrologue);
StartFunction(FD, C.VoidTy, Fn, FI, args);
- ArtificialLocation AL(*this);
+ // Create a scope with an artificial location for the body of this function.
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial);
llvm::Type *structPtrTy = blockInfo.StructureType->getPointerTo();
@@ -1500,9 +1500,9 @@
nullptr, SC_Static,
false, false);
// Create a scope with an artificial location for the body of this function.
- ApplyDebugLocation NL(*this);
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::MarkAsPrologue);
StartFunction(FD, C.VoidTy, Fn, FI, args);
- ArtificialLocation AL(*this);
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial);
llvm::Type *structPtrTy = blockInfo.StructureType->getPointerTo();
diff --git a/clang/lib/CodeGen/CGCleanup.cpp b/clang/lib/CodeGen/CGCleanup.cpp
index 18ed3e5..a75a7af 100644
--- a/clang/lib/CodeGen/CGCleanup.cpp
+++ b/clang/lib/CodeGen/CGCleanup.cpp
@@ -861,7 +861,7 @@
// Emit the EH cleanup if required.
if (RequiresEHCleanup) {
- ApplyDebugLocation AutoRestoreLocation(*this, CurEHLocation);
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial, CurEHLocation);
CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 38a1184..3fb8393 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -52,28 +52,34 @@
"Region stack mismatch, stack not empty!");
}
-ArtificialLocation::ArtificialLocation(CodeGenFunction &CGF)
- : ApplyDebugLocation(CGF) {
- if (auto *DI = CGF.getDebugInfo()) {
- // Construct a location that has a valid scope, but no line info.
- assert(!DI->LexicalBlockStack.empty());
- llvm::DIDescriptor Scope(DI->LexicalBlockStack.back());
- CGF.Builder.SetCurrentDebugLocation(llvm::DebugLoc::get(0, 0, Scope));
- }
-}
-
ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
SourceLocation TemporaryLocation)
: CGF(CGF) {
+ assert(!TemporaryLocation.isInvalid() && "invalid location");
init(TemporaryLocation);
}
-void ApplyDebugLocation::init(SourceLocation TemporaryLocation) {
+ApplyDebugLocation::ApplyDebugLocation(CodeGenFunction &CGF,
+ bool MarkAsPrologue,
+ SourceLocation TemporaryLocation)
+ : CGF(CGF) {
+ init(TemporaryLocation, MarkAsPrologue);
+}
+
+void ApplyDebugLocation::init(SourceLocation TemporaryLocation,
+ bool MarkAsPrologue) {
if (auto *DI = CGF.getDebugInfo()) {
OriginalLocation = CGF.Builder.getCurrentDebugLocation();
- if (TemporaryLocation.isInvalid())
- CGF.Builder.SetCurrentDebugLocation(llvm::DebugLoc());
- else
+ if (TemporaryLocation.isInvalid()) {
+ if (MarkAsPrologue)
+ CGF.Builder.SetCurrentDebugLocation(llvm::DebugLoc());
+ else {
+ // Construct a location that has a valid scope, but no line info.
+ assert(!DI->LexicalBlockStack.empty());
+ llvm::DIDescriptor Scope(DI->LexicalBlockStack.back());
+ CGF.Builder.SetCurrentDebugLocation(llvm::DebugLoc::get(0, 0, Scope));
+ }
+ } else
DI->EmitLocation(CGF.Builder, TemporaryLocation);
}
}
diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
index e3d6724..2f0c3f5 100644
--- a/clang/lib/CodeGen/CGDebugInfo.h
+++ b/clang/lib/CodeGen/CGDebugInfo.h
@@ -47,7 +47,7 @@
/// and is responsible for emitting to llvm globals or pass directly to
/// the backend.
class CGDebugInfo {
- friend class ArtificialLocation;
+ friend class ApplyDebugLocation;
friend class SaveAndRestoreLocation;
CodeGenModule &CGM;
const CodeGenOptions::DebugInfoKind DebugKind;
@@ -447,38 +447,36 @@
/// location or preferred location of the specified Expr.
class ApplyDebugLocation {
private:
- void init(SourceLocation TemporaryLocation);
+ void init(SourceLocation TemporaryLocation, bool MarkAsPrologue = false);
protected:
llvm::DebugLoc OriginalLocation;
CodeGenFunction &CGF;
public:
- /// If TemporaryLocation is invalid, the IRBuilder will be set to not attach
- /// debug locations, thus marking the instructions as prologue.
- ApplyDebugLocation(CodeGenFunction &CGF,
+ enum { Artificial = false, MarkAsPrologue = true, NoLocation = true };
+
+ /// \brief Set the location to the (valid) TemporaryLocation.
+ ApplyDebugLocation(CodeGenFunction &CGF, SourceLocation TemporaryLocation);
+ /// \brief Apply TemporaryLocation if it is valid, or apply a default
+ /// location: If MarkAsPrologue is true, the IRBuilder will be set to not
+ /// attach debug locations, thus marking the instructions as
+ /// prologue. Otherwise this switches to an artificial debug location that has
+ /// a valid scope, but no line information.
+ ///
+ /// Artificial locations are useful when emitting compiler-generated helper
+ /// functions that have no source location associated with them. The DWARF
+ /// specification allows the compiler to use the special line number 0 to
+ /// indicate code that can not be attributed to any source location. Note that
+ /// passing an empty SourceLocation to CGDebugInfo::setLocation() will result
+ /// in the last valid location being reused.
+ ApplyDebugLocation(CodeGenFunction &CGF, bool MarkAsPrologue,
SourceLocation TemporaryLocation = SourceLocation());
ApplyDebugLocation(CodeGenFunction &CGF, const Expr *E);
ApplyDebugLocation(CodeGenFunction &CGF, llvm::DebugLoc Loc);
~ApplyDebugLocation();
};
-/// \brief An RAII object that temporarily switches to
-/// an artificial debug location that has a valid scope, but no line
-/// information. This is useful when emitting compiler-generated
-/// helper functions that have no source location associated with
-/// them. The DWARF specification allows the compiler to use the
-/// special line number 0 to indicate code that can not be attributed
-/// to any source location.
-///
-/// This is necessary because passing an empty SourceLocation to
-/// CGDebugInfo::setLocation() will result in the last valid location
-/// being reused.
-class ArtificialLocation : public ApplyDebugLocation {
-public:
- ArtificialLocation(CodeGenFunction &CGF);
-};
-
} // namespace CodeGen
} // namespace clang
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 766d2aa..bada6ea 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -1090,7 +1090,7 @@
if (emission.wasEmittedAsGlobal()) return;
const VarDecl &D = *emission.Variable;
- ApplyDebugLocation DL(*this, D.getLocation());
+ ApplyDebugLocation DL(*this, ApplyDebugLocation::Artificial, D.getLocation());
QualType type = D.getType();
// If this local has an initializer, emit it now.
diff --git a/clang/lib/CodeGen/CGDeclCXX.cpp b/clang/lib/CodeGen/CGDeclCXX.cpp
index 3b379b7..6303db6 100644
--- a/clang/lib/CodeGen/CGDeclCXX.cpp
+++ b/clang/lib/CodeGen/CGDeclCXX.cpp
@@ -469,11 +469,11 @@
ArrayRef<llvm::Function *> Decls,
llvm::GlobalVariable *Guard) {
{
- ApplyDebugLocation NL(*this);
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::MarkAsPrologue);
StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
getTypes().arrangeNullaryFunction(), FunctionArgList());
// Emit an artificial location for this function.
- ArtificialLocation AL(*this);
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial);
llvm::BasicBlock *ExitBlock = nullptr;
if (Guard) {
@@ -520,11 +520,11 @@
const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
&DtorsAndObjects) {
{
- ApplyDebugLocation NL(*this);
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::MarkAsPrologue);
StartFunction(GlobalDecl(), getContext().VoidTy, Fn,
getTypes().arrangeNullaryFunction(), FunctionArgList());
// Emit an artificial location for this function.
- ArtificialLocation AL(*this);
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial);
// Emit the dtors, in reverse order from construction.
for (unsigned i = 0, e = DtorsAndObjects.size(); i != e; ++i) {
diff --git a/clang/lib/CodeGen/CGException.cpp b/clang/lib/CodeGen/CGException.cpp
index 9f886eb..406afb2 100644
--- a/clang/lib/CodeGen/CGException.cpp
+++ b/clang/lib/CodeGen/CGException.cpp
@@ -770,7 +770,7 @@
// Save the current IR generation state.
CGBuilderTy::InsertPoint savedIP = Builder.saveAndClearIP();
- ApplyDebugLocation AutoRestoreLocation(*this, CurEHLocation);
+ ApplyDebugLocation AL(*this, ApplyDebugLocation::Artificial, CurEHLocation);
const EHPersonality &personality = EHPersonality::get(CGM);
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 2e2821b..503f9b1 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -3043,7 +3043,7 @@
// Emit an unconditional branch from this block to ContBlock.
{
// There is no need to emit line number for unconditional branch.
- ApplyDebugLocation DL(CGF);
+ ApplyDebugLocation NL(CGF, ApplyDebugLocation::NoLocation);
CGF.EmitBlock(ContBlock);
}
// Insert an entry into the phi node for the edge with the value of RHSCond.
diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index e3bdf86..be2ddf6 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/lib/CodeGen/CGStmt.cpp
@@ -564,8 +564,8 @@
// Emit the 'else' code if present.
if (const Stmt *Else = S.getElse()) {
{
- // There is no need to emit line number for unconditional branch.
- ApplyDebugLocation DL(*this);
+ // There is no need to emit line number for an unconditional branch.
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::NoLocation);
EmitBlock(ElseBlock);
}
{
@@ -573,8 +573,8 @@
EmitStmt(Else);
}
{
- // There is no need to emit line number for unconditional branch.
- ApplyDebugLocation DL(*this);
+ // There is no need to emit line number for an unconditional branch.
+ ApplyDebugLocation NL(*this, ApplyDebugLocation::NoLocation);
EmitBranch(ContBlock);
}
}
diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 60958d0..395f6fa 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -86,13 +86,13 @@
// Emit the 'else' code if present.
{
// There is no need to emit line number for unconditional branch.
- ApplyDebugLocation DL(CGF);
+ ApplyDebugLocation NL(CGF, ApplyDebugLocation::NoLocation);
CGF.EmitBlock(ElseBlock);
}
CodeGen(/*ThenBlock*/ false);
{
// There is no need to emit line number for unconditional branch.
- ApplyDebugLocation DL(CGF);
+ ApplyDebugLocation NL(CGF, ApplyDebugLocation::NoLocation);
CGF.EmitBranch(ContBlock);
}
// Emit the continuation block for code after the if.