Add LLVM IR debug info support for Fortran COMMON blocks
COMMON blocks are a feature of Fortran that has no direct analog in C languages, but they are similar to data sections in assembly language programming. A COMMON block is a named area of memory that holds a collection of variables. Fortran subprograms may map the COMMON block memory area to their own, possibly distinct, non-empty list of variables. A Fortran COMMON block might look like the following example.
COMMON /ALPHA/ I, J
For this construct, the compiler generates a new scope-like DI construct (!DICommonBlock) into which variables (see I, J above) can be placed. As the common block implies a range of storage with global lifetime, the !DICommonBlock refers to a !DIGlobalVariable. The Fortran variable that comprise the COMMON block are also linked via metadata to offsets within the global variable that stands for the entire common block.
@alpha_ = common global %alphabytes_ zeroinitializer, align 64, !dbg !27, !dbg !30, !dbg !33
!14 = distinct !DISubprogram(…)
!20 = distinct !DICommonBlock(scope: !14, declaration: !25, name: "alpha")
!25 = distinct !DIGlobalVariable(scope: !20, name: "common alpha", type: !24)
!27 = !DIGlobalVariableExpression(var: !25, expr: !DIExpression())
!29 = distinct !DIGlobalVariable(scope: !20, name: "i", file: !3, type: !28)
!30 = !DIGlobalVariableExpression(var: !29, expr: !DIExpression())
!31 = distinct !DIGlobalVariable(scope: !20, name: "j", file: !3, type: !28)
!32 = !DIExpression(DW_OP_plus_uconst, 4)
!33 = !DIGlobalVariableExpression(var: !31, expr: !32)
The DWARF generated for this is as follows.
DW_TAG_common_block:
DW_AT_name: alpha
DW_AT_location: @alpha_+0
DW_TAG_variable:
DW_AT_name: common alpha
DW_AT_type: array of 8 bytes
DW_AT_location: @alpha_+0
DW_TAG_variable:
DW_AT_name: i
DW_AT_type: integer*4
DW_AT_location: @Alpha+0
DW_TAG_variable:
DW_AT_name: j
DW_AT_type: integer*4
DW_AT_location: @Alpha+4
Patch by Eric Schweitz!
Differential Revision: https://reviews.llvm.org/D54327
llvm-svn: 357934
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index 1ab2702..f14ef36 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -4664,6 +4664,24 @@
return false;
}
+/// ParseDICommonBlock:
+/// ::= !DICommonBlock(scope: !0, file: !2, name: "COMMON name", line: 9)
+bool LLParser::ParseDICommonBlock(MDNode *&Result, bool IsDistinct) {
+#define VISIT_MD_FIELDS(OPTIONAL, REQUIRED) \
+ REQUIRED(scope, MDField, ); \
+ OPTIONAL(declaration, MDField, ); \
+ OPTIONAL(name, MDStringField, ); \
+ OPTIONAL(file, MDField, ); \
+ OPTIONAL(line, LineField, );
+ PARSE_MD_FIELDS();
+#undef VISIT_MD_FIELDS
+
+ Result = GET_OR_DISTINCT(DICommonBlock,
+ (Context, scope.Val, declaration.Val, name.Val,
+ file.Val, line.Val));
+ return false;
+}
+
/// ParseDINamespace:
/// ::= !DINamespace(scope: !0, file: !2, name: "SomeNamespace", line: 9)
bool LLParser::ParseDINamespace(MDNode *&Result, bool IsDistinct) {
diff --git a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
index 089038c..d270c4c 100644
--- a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
+++ b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
@@ -811,6 +811,7 @@
case bitc::METADATA_LEXICAL_BLOCK:
case bitc::METADATA_LEXICAL_BLOCK_FILE:
case bitc::METADATA_NAMESPACE:
+ case bitc::METADATA_COMMON_BLOCK:
case bitc::METADATA_MACRO:
case bitc::METADATA_MACRO_FILE:
case bitc::METADATA_TEMPLATE_TYPE:
@@ -1528,6 +1529,17 @@
NextMetadataNo++;
break;
}
+ case bitc::METADATA_COMMON_BLOCK: {
+ IsDistinct = Record[0] & 1;
+ MetadataList.assignValue(
+ GET_OR_DISTINCT(DICommonBlock,
+ (Context, getMDOrNull(Record[1]),
+ getMDOrNull(Record[2]), getMDString(Record[3]),
+ getMDOrNull(Record[4]), Record[5])),
+ NextMetadataNo);
+ NextMetadataNo++;
+ break;
+ }
case bitc::METADATA_NAMESPACE: {
// Newer versions of DINamespace dropped file and line.
MDString *Name;
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 1d6480c..c835976 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -317,6 +317,8 @@
void writeDILexicalBlockFile(const DILexicalBlockFile *N,
SmallVectorImpl<uint64_t> &Record,
unsigned Abbrev);
+ void writeDICommonBlock(const DICommonBlock *N,
+ SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
void writeDINamespace(const DINamespace *N, SmallVectorImpl<uint64_t> &Record,
unsigned Abbrev);
void writeDIMacro(const DIMacro *N, SmallVectorImpl<uint64_t> &Record,
@@ -1686,6 +1688,20 @@
Record.clear();
}
+void ModuleBitcodeWriter::writeDICommonBlock(const DICommonBlock *N,
+ SmallVectorImpl<uint64_t> &Record,
+ unsigned Abbrev) {
+ Record.push_back(N->isDistinct());
+ Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+ Record.push_back(VE.getMetadataOrNullID(N->getDecl()));
+ Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+ Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+ Record.push_back(N->getLineNo());
+
+ Stream.EmitRecord(bitc::METADATA_COMMON_BLOCK, Record, Abbrev);
+ Record.clear();
+}
+
void ModuleBitcodeWriter::writeDINamespace(const DINamespace *N,
SmallVectorImpl<uint64_t> &Record,
unsigned Abbrev) {
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index fbb7a57..c1e8ffe 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -123,7 +123,9 @@
// Construct the context before querying for the existence of the DIE in
// case such construction creates the DIE.
- DIE *ContextDIE = getOrCreateContextDIE(GVContext);
+ auto *CB = GVContext ? dyn_cast<DICommonBlock>(GVContext) : nullptr;
+ DIE *ContextDIE = CB ? getOrCreateCommonBlock(CB, GlobalExprs)
+ : getOrCreateContextDIE(GVContext);
// Add to map.
DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
@@ -166,6 +168,13 @@
addTemplateParams(*VariableDIE, DINodeArray(TP));
// Add location.
+ addLocationAttribute(VariableDIE, GV, GlobalExprs);
+
+ return VariableDIE;
+}
+
+void DwarfCompileUnit::addLocationAttribute(
+ DIE *VariableDIE, const DIGlobalVariable *GV, ArrayRef<GlobalExpr> GlobalExprs) {
bool addToAccelTable = false;
DIELoc *Loc = nullptr;
Optional<unsigned> NVPTXAddressSpace;
@@ -288,8 +297,25 @@
DD->useAllLinkageNames())
DD->addAccelName(*CUNode, GV->getLinkageName(), *VariableDIE);
}
+}
- return VariableDIE;
+DIE *DwarfCompileUnit::getOrCreateCommonBlock(
+ const DICommonBlock *CB, ArrayRef<GlobalExpr> GlobalExprs) {
+ // Construct the context before querying for the existence of the DIE in case
+ // such construction creates the DIE.
+ DIE *ContextDIE = getOrCreateContextDIE(CB->getScope());
+
+ if (DIE *NDie = getDIE(CB))
+ return NDie;
+ DIE &NDie = createAndAddDIE(dwarf::DW_TAG_common_block, *ContextDIE, CB);
+ StringRef Name = CB->getName().empty() ? "_BLNK_" : CB->getName();
+ addString(NDie, dwarf::DW_AT_name, Name);
+ addGlobalName(Name, NDie, CB->getScope());
+ if (CB->getFile())
+ addSourceLine(NDie, CB->getLineNo(), CB->getFile());
+ if (DIGlobalVariable *V = CB->getDecl())
+ getCU().addLocationAttribute(&NDie, V, GlobalExprs);
+ return &NDie;
}
void DwarfCompileUnit::addRange(RangeSpan Range) {
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
index d9addb5..4d66447 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
@@ -139,6 +139,12 @@
getOrCreateGlobalVariableDIE(const DIGlobalVariable *GV,
ArrayRef<GlobalExpr> GlobalExprs);
+ DIE *getOrCreateCommonBlock(const DICommonBlock *CB,
+ ArrayRef<GlobalExpr> GlobalExprs);
+
+ void addLocationAttribute(DIE *ToDIE, const DIGlobalVariable *GV,
+ ArrayRef<GlobalExpr> GlobalExprs);
+
/// addLabelAddress - Add a dwarf label attribute data and value using
/// either DW_FORM_addr or DW_FORM_GNU_addr_index.
void addLabelAddress(DIE &Die, dwarf::Attribute Attribute,
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index bc395ec..eec1028 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -689,7 +689,7 @@
DD->addAccelType(*CUNode, Ty->getName(), TyDIE, Flags);
if (!Context || isa<DICompileUnit>(Context) || isa<DIFile>(Context) ||
- isa<DINamespace>(Context))
+ isa<DINamespace>(Context) || isa<DICommonBlock>(Context))
addGlobalType(Ty, TyDIE, Context);
}
}
diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index ad6c2c8..376262b 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -2001,6 +2001,19 @@
Out << ")";
}
+static void writeDICommonBlock(raw_ostream &Out, const DICommonBlock *N,
+ TypePrinting *TypePrinter, SlotTracker *Machine,
+ const Module *Context) {
+ Out << "!DICommonBlock(";
+ MDFieldPrinter Printer(Out, TypePrinter, Machine, Context);
+ Printer.printMetadata("scope", N->getRawScope(), false);
+ Printer.printMetadata("declaration", N->getRawDecl(), false);
+ Printer.printString("name", N->getName());
+ Printer.printMetadata("file", N->getRawFile());
+ Printer.printInt("line", N->getLineNo());
+ Out << ")";
+}
+
static void writeDIMacro(raw_ostream &Out, const DIMacro *N,
TypePrinting *TypePrinter, SlotTracker *Machine,
const Module *Context) {
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index c248740..0cd3370 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -805,6 +805,13 @@
return SP;
}
+DICommonBlock *DIBuilder::createCommonBlock(
+ DIScope *Scope, DIGlobalVariable *Decl, StringRef Name, DIFile *File,
+ unsigned LineNo) {
+ return DICommonBlock::get(
+ VMContext, Scope, Decl, Name, File, LineNo);
+}
+
DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
bool ExportSymbols) {
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index 0ae408a..7158e57 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -222,6 +222,9 @@
if (auto *NS = dyn_cast<DINamespace>(this))
return NS->getScope();
+ if (auto *CB = dyn_cast<DICommonBlock>(this))
+ return CB->getScope();
+
if (auto *M = dyn_cast<DIModule>(this))
return M->getScope();
@@ -237,6 +240,8 @@
return SP->getName();
if (auto *NS = dyn_cast<DINamespace>(this))
return NS->getName();
+ if (auto *CB = dyn_cast<DICommonBlock>(this))
+ return CB->getName();
if (auto *M = dyn_cast<DIModule>(this))
return M->getName();
assert((isa<DILexicalBlockBase>(this) || isa<DIFile>(this) ||
@@ -694,6 +699,17 @@
DEFINE_GETIMPL_STORE(DINamespace, (ExportSymbols), Ops);
}
+DICommonBlock *DICommonBlock::getImpl(LLVMContext &Context, Metadata *Scope,
+ Metadata *Decl, MDString *Name,
+ Metadata *File, unsigned LineNo,
+ StorageType Storage, bool ShouldCreate) {
+ assert(isCanonical(Name) && "Expected canonical MDString");
+ DEFINE_GETIMPL_LOOKUP(DICommonBlock, (Scope, Decl, Name, File, LineNo));
+ // The nullptr is for DIScope's File operand. This should be refactored.
+ Metadata *Ops[] = {Scope, Decl, Name, File};
+ DEFINE_GETIMPL_STORE(DICommonBlock, (LineNo), Ops);
+}
+
DIModule *DIModule::getImpl(LLVMContext &Context, Metadata *Scope,
MDString *Name, MDString *ConfigurationMacros,
MDString *IncludePath, MDString *ISysRoot,
diff --git a/llvm/lib/IR/LLVMContextImpl.h b/llvm/lib/IR/LLVMContextImpl.h
index 42dd471..aaa765b 100644
--- a/llvm/lib/IR/LLVMContextImpl.h
+++ b/llvm/lib/IR/LLVMContextImpl.h
@@ -789,6 +789,31 @@
}
};
+template <> struct MDNodeKeyImpl<DICommonBlock> {
+ Metadata *Scope;
+ Metadata *Decl;
+ MDString *Name;
+ Metadata *File;
+ unsigned LineNo;
+
+ MDNodeKeyImpl(Metadata *Scope, Metadata *Decl, MDString *Name,
+ Metadata *File, unsigned LineNo)
+ : Scope(Scope), Decl(Decl), Name(Name), File(File), LineNo(LineNo) {}
+ MDNodeKeyImpl(const DICommonBlock *N)
+ : Scope(N->getRawScope()), Decl(N->getRawDecl()), Name(N->getRawName()),
+ File(N->getRawFile()), LineNo(N->getLineNo()) {}
+
+ bool isKeyOf(const DICommonBlock *RHS) const {
+ return Scope == RHS->getRawScope() && Decl == RHS->getRawDecl() &&
+ Name == RHS->getRawName() && File == RHS->getRawFile() &&
+ LineNo == RHS->getLineNo();
+ }
+
+ unsigned getHashValue() const {
+ return hash_combine(Scope, Decl, Name, File, LineNo);
+ }
+};
+
template <> struct MDNodeKeyImpl<DIModule> {
Metadata *Scope;
MDString *Name;
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index c371087..837f2d0 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1156,6 +1156,14 @@
visitDILexicalBlockBase(N);
}
+void Verifier::visitDICommonBlock(const DICommonBlock &N) {
+ AssertDI(N.getTag() == dwarf::DW_TAG_common_block, "invalid tag", &N);
+ if (auto *S = N.getRawScope())
+ AssertDI(isa<DIScope>(S), "invalid scope ref", &N, S);
+ if (auto *S = N.getRawDecl())
+ AssertDI(isa<DIGlobalVariable>(S), "invalid declaration", &N, S);
+}
+
void Verifier::visitDINamespace(const DINamespace &N) {
AssertDI(N.getTag() == dwarf::DW_TAG_namespace, "invalid tag", &N);
if (auto *S = N.getRawScope())
@@ -1224,7 +1232,6 @@
visitDIVariable(N);
AssertDI(N.getTag() == dwarf::DW_TAG_variable, "invalid tag", &N);
- AssertDI(!N.getName().empty(), "missing global variable name", &N);
AssertDI(isType(N.getRawType()), "invalid type ref", &N, N.getRawType());
AssertDI(N.getType(), "missing global variable type", &N);
if (auto *Member = N.getRawStaticDataMemberDeclaration()) {