// The location where the IR file is emitted is the same as the directory
// operand of the !llvm.dbg.cu metadata node present in the input module. The
// file name is constructed from the original file name by stripping the
-// extension and replacing it with "-debug.ll" or the Postfix string specified
+// extension and replacing it with "-debug-ll" or the Postfix string specified
// at construction.
//
// FIXME: instead of replacing debug metadata, additional metadata should be
#include <string>
-#include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/ValueMap.h"
+#include "llvm/Assembly/AssemblyAnnotationWriter.h"
#include "llvm/DebugInfo.h"
#include "llvm/DIBuilder.h"
-#include "llvm/IR/AsmWriter.h"
+#include "llvm/InstVisitor.h"
#include "llvm/IR/Instruction.h"
-#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Transforms/Instrumentation.h"
+#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ToolOutputFile.h"
-#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/FormattedStream.h"
using namespace llvm;
namespace {
-/// Returns true if Node's name contains the string "llvm.dbg"
-bool isDebugNamedMetadata(const NamedMDNode *Node) {
- return Node->getName().str().find("llvm.dbg") != std::string::npos;
-}
+/// Builds a map of Value* to line numbers on which the Value appears in a
+/// textual representation of the IR by plugging into the AssemblyWriter by
+/// masquerading as an AssemblyAnnotationWriter.
+class ValueToLineMap : public AssemblyAnnotationWriter {
+ ValueMap<const Value *, unsigned int> Lines;
+ typedef ValueMap<const Value *, unsigned int>::const_iterator LineIter;
-/// Returns true if Inst is a call to llvm.dbg.value or llvm.dbg.declare
-bool isDebugIntrinsic(const IntrinsicInst *Inst) {
- Intrinsic::ID id = Inst->getIntrinsicID();
- return id == Intrinsic::dbg_value || id == Intrinsic::dbg_declare;
-}
+public:
-/// An AssemblyWriter which generates a succinct representation of the module
-/// (without debug intrinsics or metadata) suitable for debugging. As IR
-/// instructions are printed, !dbg metadata nodes are added (or updated)
-/// to point to the corresponding line in the generated IR file instead
-/// of the original source file. The input module must have been constructed
-/// with debug metadata (i.e. clang -g).
-class IRDebugInfoHelper : public llvm::AssemblyWriter {
- /// Directory of debug metadata
- const DebugInfoFinder &Finder;
+ /// Prints Module to a null buffer in order to build the map of Value pointers
+ /// to line numbers.
+ ValueToLineMap(Module *M) {
+ raw_null_ostream ThrowAway;
+ M->print(ThrowAway, this);
+ }
- /// Flags to control the verbosity of the generated IR file
- bool hideDebugIntrinsics;
- bool hideDebugMetadata;
+ // This function is called after an Instruction, GlobalValue, or GlobalAlias
+ // is printed.
+ void printInfoComment(const Value &V, formatted_raw_ostream &Out) {
+ Out.flush();
+ Lines.insert(std::make_pair(&V, Out.getLine() + 1));
+ }
+
+ /// If V appears on a line in the textual IR representation, sets Line to the
+ /// line number and returns true, otherwise returns false.
+ bool getLine(const Value *V, unsigned int &Line) const {
+ LineIter i = Lines.find(V);
+ if (i != Lines.end()) {
+ Line = i->second;
+ return true;
+ }
+ return false;
+ }
+};
- /// Set to track metadata nodes to be printed (used only when
- /// printDebugMetadata == false)
- SmallSet<const MDNode *, 4> NonDebugNodes;
+/// Removes debug intrisncs like llvm.dbg.declare and llvm.dbg.value.
+class DebugIntrinsicsRemover : public InstVisitor<DebugIntrinsicsRemover> {
+ void remove(Instruction &I) { I.eraseFromParent(); }
public:
- IRDebugInfoHelper(
- formatted_raw_ostream &o, const Module *M,
- AssemblyAnnotationWriter *AAW, const DebugInfoFinder &Finder,
- bool hideDebugIntrinsics = true, bool hideDebugMetadata = true)
- : AssemblyWriter(o, M, AAW), Finder(Finder),
- hideDebugIntrinsics(hideDebugIntrinsics),
- hideDebugMetadata(hideDebugMetadata) {}
+ void visitDbgDeclareInst(DbgDeclareInst &I) { remove(I); }
+ void visitDbgValueInst(DbgValueInst &I) { remove(I); }
+ void visitDbgInfoIntrinsic(DbgInfoIntrinsic &I) { remove(I); }
+};
-private:
- virtual void printInstruction(const Instruction &I) {
- DebugLoc Loc(I.getDebugLoc());
+/// Removes debug metadata (!dbg) nodes from all instructions as well as
+/// metadata named "llvm.dbg.cu" in the Module.
+class DebugMetadataRemover : public InstVisitor<DebugMetadataRemover> {
+public:
+ void visitInstruction(Instruction &I) {
+ if (I.getMetadata(LLVMContext::MD_dbg))
+ I.setMetadata(LLVMContext::MD_dbg, 0);
+ }
- if (hideDebugMetadata)
- removeDebugMetadata(const_cast<Instruction &>(I));
+ void run(Module *M) {
+ // Remove debug metadata attached to instructions
+ visit(M);
- AssemblyWriter::printInstruction(I);
- Out.flush();
- // Adjust line number by 1 because we have not yet printed the \n
- unsigned Line = Out.getLine() + 1;
+ // Remove CU named metadata (and all children nodes)
+ NamedMDNode *Node = M->getNamedMetadata("llvm.dbg.cu");
+ M->eraseNamedMetadata(Node);
+ }
+};
+
+/// Replaces line number metadata attached to Instruction nodes with new line
+/// numbers provided by the ValueToLineMap.
+class LineNumberReplacer : public InstVisitor<LineNumberReplacer> {
+ /// Table of line numbers
+ const ValueToLineMap &LineTable;
+
+ /// Table of cloned values
+ const ValueToValueMapTy &VMap;
+
+ /// Directory of debug metadata
+ const DebugInfoFinder &Finder;
+
+public:
+ LineNumberReplacer(const ValueToLineMap &VLM, const DebugInfoFinder &Finder,
+ const ValueToValueMapTy &VMap)
+ : LineTable(VLM), VMap(VMap), Finder(Finder) {}
+
+ void visitInstruction(Instruction &I) {
+ DebugLoc Loc(I.getDebugLoc());
+
+ unsigned Col = 0; // FIXME: support columns
+ unsigned Line;
+ if (!LineTable.getLine(VMap.lookup(&I), Line))
+ // Instruction has no line, it may have been removed (in the module that
+ // will be passed to the debugger) so there is nothing to do here.
+ return;
DebugLoc NewLoc;
if (!Loc.isUnknown())
// I had a previous debug location: re-use the DebugLoc
- NewLoc = DebugLoc::get(Line, /* FIXME: support columns */ 0,
- Loc.getScope(I.getContext()),
+ NewLoc = DebugLoc::get(Line, Col, Loc.getScope(I.getContext()),
Loc.getInlinedAt(I.getContext()));
else if (MDNode *scope = findFunctionMD(I.getParent()->getParent()))
// I had no previous debug location, but M has some debug information
- NewLoc = DebugLoc::get(Line, 0, scope, /*FIXME: inlined instructions*/ 0);
+ NewLoc =
+ DebugLoc::get(Line, Col, scope, /*FIXME: inlined instructions*/ 0);
else
// Neither I nor M has any debug information -- nothing to do here.
// FIXME: support debugging of undecorated IR (generated by clang without
// the -g option)
return;
- if (hideDebugMetadata)
- saveNonDebugMetadata(I);
-
addDebugLocation(const_cast<Instruction &>(I), NewLoc);
}
- virtual void printInstructionLine(const Instruction &I) {
- if (hideDebugIntrinsics)
- if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(&I))
- if (isDebugIntrinsic(II))
- return;
- AssemblyWriter::printInstructionLine(I);
- }
-
- virtual void writeMDNode(unsigned Slot, const MDNode *Node) {
- if (hideDebugMetadata == false || isDebugMetadata(Node) == false)
- AssemblyWriter::writeMDNode(Slot, Node);
- }
-
- virtual void printNamedMDNode(const NamedMDNode *NMD) {
- if (hideDebugMetadata == false || isDebugNamedMetadata(NMD) == false)
- AssemblyWriter::printNamedMDNode(NMD);
- }
+private:
/// Returns the MDNode that corresponds with F
MDNode *findFunctionMD(const Function *F) {
return 0;
}
- /// Saves all non-debug metadata attached to I
- void saveNonDebugMetadata(const Instruction &I) {
- typedef SmallVector<std::pair<unsigned, MDNode *>, 4> MDNodeVector;
- MDNodeVector Others;
- I.getAllMetadataOtherThanDebugLoc(Others);
- for (MDNodeVector::iterator i = Others.begin(), e = Others.end(); i != e;
- ++i)
- NonDebugNodes.insert(i->second);
- }
-
- /// Returns true if Node was not saved as non-debug metadata with
- /// saveNonDebugMetadata(), false otherwise.
- bool isDebugMetadata(const MDNode *Node) {
- return NonDebugNodes.count(Node) == 0;
- }
-
- void removeDebugMetadata(Instruction &I) {
- if (I.getMetadata(LLVMContext::MD_dbg))
- I.setMetadata(LLVMContext::MD_dbg, 0);
- }
-
void addDebugLocation(Instruction &I, DebugLoc Loc) {
MDNode *MD = Loc.getAsMDNode(I.getContext());
I.setMetadata(LLVMContext::MD_dbg, MD);
class DebugIR : public ModulePass {
std::string Postfix;
std::string Filename;
- DebugInfoFinder Finder;
+
+ /// Flags to control the verbosity of the generated IR file
+ bool hideDebugIntrinsics;
+ bool hideDebugMetadata;
public:
static char ID;
- DebugIR() : ModulePass(ID), Postfix("-debug.ll") {}
+ const char *getPassName() const { return "DebugIR"; }
+
+ // FIXME: figure out if we are compiling something that already exists on disk
+ // in text IR form, in which case we can omit outputting a new IR file, or if
+ // we're building something from memory where we actually need to emit a new
+ // IR file for the debugger.
+
+ /// Output a file with the same base name as the original, but with the
+ /// postfix "-debug-ll" appended.
+ DebugIR()
+ : ModulePass(ID), Postfix("-debug-ll"), hideDebugIntrinsics(true),
+ hideDebugMetadata(true) {}
/// Customize the postfix string used to replace the extension of the
/// original filename that appears in the !llvm.dbg.cu metadata node.
- DebugIR(StringRef postfix) : ModulePass(ID), Postfix(postfix) {}
+ DebugIR(StringRef postfix, bool hideDebugIntrinsics, bool hideDebugMetadata)
+ : ModulePass(ID), Postfix(postfix),
+ hideDebugIntrinsics(hideDebugIntrinsics),
+ hideDebugMetadata(hideDebugMetadata) {}
private:
// Modify the filename embedded in the Compilation-Unit debug information of M
- bool replaceFilename(Module &M) {
+ bool replaceFilename(Module &M, const DebugInfoFinder &Finder) {
bool changed = false;
// Sanity check -- if llvm.dbg.cu node exists, the DebugInfoFinder
return changed;
}
- void writeAndUpdateDebugIRFile(Module *M) {
+ /// Replace existing line number metadata with line numbers that correspond
+ /// with the IR file that is seen by the debugger.
+ void addLineNumberMetadata(Module *M, const ValueToLineMap &VLM,
+ const ValueToValueMapTy &VMap,
+ const DebugInfoFinder &Finder) {
+ LineNumberReplacer Replacer(VLM, Finder, VMap);
+ Replacer.visit(M);
+ }
+
+ void writeDebugBitcode(Module *M) {
std::string error;
tool_output_file OutFile(Filename.c_str(), error);
OutFile.keep();
formatted_raw_ostream OS;
- OS.setStream(OutFile.os(), false);
+ OS.setStream(OutFile.os());
+ M->print(OS, 0);
+ }
+
+ void removeDebugIntrinsics(Module *M) {
+ DebugIntrinsicsRemover Remover;
+ Remover.visit(M);
+ }
+
+ void removeDebugMetadata(Module *M) {
+ DebugMetadataRemover Remover;
+ Remover.run(M);
+ }
+
+ void updateAndWriteDebugIRFile(Module *M, const DebugInfoFinder &Finder) {
+ // The module we output in text form for a debugger to open is stripped of
+ // 'extras' like debug intrinsics that end up in DWARF anyways and just
+ // clutter the debug experience.
+
+ ValueToValueMapTy VMap;
+ Module *DebuggerM = CloneModule(M, VMap);
+
+ if (hideDebugIntrinsics)
+ removeDebugIntrinsics(DebuggerM);
- IRDebugInfoHelper W(OS, M, 0, Finder);
- W.printModule(M);
+ if (hideDebugMetadata)
+ removeDebugMetadata(DebuggerM);
+
+ // FIXME: remove all debug metadata from M once we support generating DWARF
+ // subprogram attributes.
+
+ ValueToLineMap LineTable(DebuggerM);
+ addLineNumberMetadata(M, LineTable, VMap, Finder);
+ writeDebugBitcode(DebuggerM);
}
bool runOnModule(Module &M) {
+ // Stores existing debug info needed when creating new line number entries.
+ DebugInfoFinder Finder;
Finder.processModule(M);
- bool changed = replaceFilename(M);
+
+ bool changed = replaceFilename(M, Finder);
if (changed)
- writeAndUpdateDebugIRFile(&M);
+ updateAndWriteDebugIRFile(&M, Finder);
return changed;
}
};
char DebugIR::ID = 0;
INITIALIZE_PASS(DebugIR, "debug-ir", "Enable debugging IR", false, false)
- ModulePass *llvm::createDebugIRPass(StringRef FilenamePostfix) {
- return new DebugIR(FilenamePostfix);
+
+ModulePass *llvm::createDebugIRPass(StringRef FilenamePostfix,
+ bool hideDebugIntrinsics,
+ bool hideDebugMetadata) {
+ return new DebugIR(FilenamePostfix, hideDebugIntrinsics, hideDebugMetadata);
}