Re-apply "[ORC] Add N_SO and N_OSO stabs entries to MachO debug..." with fixes.

This re-applies db51e57289, which was reverted in 05b1a2cb3e due to bot
failures. The DebuggerSupportPlugin now depends on DWARF, so it has been moved
to the new OrcDebugging library (as has the enableDebuggerSupport API).

clang/lib/Interpreter/CMakeLists.txt

@@ -4,6 +4,7 @@ set(LLVM_LINK_COMPONENTS
    MC
    Option
    OrcJit
+   OrcDebugging
    OrcShared
    OrcTargetProcess
    Support

clang/lib/Interpreter/IncrementalExecutor.cpp

@@ -17,7 +17,7 @@
 #include "clang/Interpreter/PartialTranslationUnit.h"
 #include "llvm/ExecutionEngine/ExecutionEngine.h"
 #include "llvm/ExecutionEngine/Orc/CompileUtils.h"
-#include "llvm/ExecutionEngine/Orc/DebuggerSupport.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupport.h"
 #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
 #include "llvm/ExecutionEngine/Orc/IRCompileLayer.h"
 #include "llvm/ExecutionEngine/Orc/LLJIT.h"

llvm/lib/ExecutionEngine/Orc/CMakeLists.txt

@@ -13,8 +13,6 @@ add_llvm_component_library(LLVMOrcJIT
   CompileUtils.cpp
   Core.cpp
   DebugObjectManagerPlugin.cpp
-  DebuggerSupport.cpp
-  DebuggerSupportPlugin.cpp
   DebugUtils.cpp
   EPCDynamicLibrarySearchGenerator.cpp
   EPCDebugObjectRegistrar.cpp

llvm/lib/ExecutionEngine/Orc/Debugging/CMakeLists.txt

@@ -4,6 +4,8 @@ endif()
 
 add_llvm_component_library(LLVMOrcDebugging
   DebugInfoSupport.cpp
+  DebuggerSupport.cpp
+  DebuggerSupportPlugin.cpp
   PerfSupportPlugin.cpp
 
   ADDITIONAL_HEADER_DIRS

llvm/lib/ExecutionEngine/Orc/Debugging/DebuggerSupport.cpp

@@ -6,9 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/ExecutionEngine/Orc/DebuggerSupport.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupport.h"
 #include "llvm/ExecutionEngine/Orc/DebugObjectManagerPlugin.h"
-#include "llvm/ExecutionEngine/Orc/DebuggerSupportPlugin.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupportPlugin.h"
 #include "llvm/ExecutionEngine/Orc/LLJIT.h"
 
 #define DEBUG_TYPE "orc"

llvm/lib/ExecutionEngine/Orc/Debugging/DebuggerSupportPlugin.cpp

@@ -9,13 +9,17 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/ExecutionEngine/Orc/DebuggerSupportPlugin.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupportPlugin.h"
 #include "llvm/ExecutionEngine/Orc/MachOBuilder.h"
 
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/BinaryFormat/MachO.h"
+#include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
+
+#include <chrono>
 
 #define DEBUG_TYPE "orc"
 
@@ -97,8 +101,6 @@ public:
              << "\n";
     });
 
-    auto &SDOSec = G.createSection(SynthDebugSectionName, MemProt::Read);
-
     for (auto &Sec : G.sections()) {
       if (Sec.blocks().empty())
         continue;
@@ -114,6 +116,10 @@ public:
         NonDebugSections.push_back({&Sec, nullptr});
     }
 
+    // Bail out early if no debug sections.
+    if (DebugSections.empty())
+      return Error::success();
+
     // Write MachO header and debug section load commands.
     Builder.Header.filetype = MachO::MH_OBJECT;
     switch (G.getTargetTriple().getArch()) {
@@ -131,16 +137,65 @@ public:
 
     Seg = &Builder.addSegment("");
 
+    StringMap<std::unique_ptr<MemoryBuffer>> DebugSectionMap;
+    StringRef DebugLineSectionData;
     for (auto &DSec : DebugSections) {
       auto [SegName, SecName] = DSec.GraphSec->getName().split(',');
       DSec.BuilderSec = &Seg->addSection(SecName, SegName);
 
       SectionRange SR(*DSec.GraphSec);
       DSec.BuilderSec->Content.Size = SR.getSize();
-      if (!SR.empty())
+      if (!SR.empty()) {
         DSec.BuilderSec->align = Log2_64(SR.getFirstBlock()->getAlignment());
+        StringRef SectionData(SR.getFirstBlock()->getContent().data(),
+                              SR.getFirstBlock()->getSize());
+        DebugSectionMap[SecName] =
+            MemoryBuffer::getMemBuffer(SectionData, G.getName(), false);
+        if (SecName == "__debug_line")
+          DebugLineSectionData = SectionData;
+      }
     }
 
+    std::optional<std::string> FileName;
+    if (!DebugLineSectionData.empty()) {
+      auto DWARFCtx = DWARFContext::create(DebugSectionMap, G.getPointerSize(),
+                                           G.getEndianness());
+      DWARFDataExtractor DebugLineData(
+          DebugLineSectionData,
+          G.getEndianness() == support::endianness::little, G.getPointerSize());
+      uint64_t Offset = 0;
+      DWARFDebugLine::LineTable LineTable;
+
+      // Try to parse line data. Consume error on failure.
+      if (auto Err = LineTable.parse(DebugLineData, &Offset, *DWARFCtx, nullptr,
+                                     consumeError)) {
+        handleAllErrors(
+          std::move(Err),
+          [&](ErrorInfoBase &EIB) {
+            LLVM_DEBUG({
+              dbgs() << "Cannot parse line table for \"" << G.getName() << "\": ";
+              EIB.log(dbgs());
+              dbgs() << "\n";
+            });
+          });
+      } else {
+        if (!LineTable.Prologue.FileNames.empty())
+          FileName = *dwarf::toString(LineTable.Prologue.FileNames[0].Name);
+      }
+    }
+
+    // If no line table (or unable to use) then use graph name.
+    // FIXME: There are probably other debug sections we should look in first.
+    if (!FileName)
+      FileName = G.getName();
+
+    Builder.addSymbol("", MachO::N_SO, 0, 0, 0);
+    Builder.addSymbol(*FileName, MachO::N_SO, 0, 0, 0);
+    auto TimeStamp = std::chrono::duration_cast<std::chrono::seconds>(
+                         std::chrono::system_clock::now().time_since_epoch())
+                         .count();
+    Builder.addSymbol("", MachO::N_OSO, 3, 1, TimeStamp);
+
     for (auto &NDSP : NonDebugSections) {
       auto [SegName, SecName] = NDSP.GraphSec->getName().split(',');
       NDSP.BuilderSec = &Seg->addSection(SecName, SegName);
@@ -164,8 +219,12 @@ public:
       }
     }
 
+    Builder.addSymbol("", MachO::N_SO, 1, 0, 0);
+
+    // Lay out the debug object, create a section and block for it.
     size_t DebugObjectSize = Builder.layout();
 
+    auto &SDOSec = G.createSection(SynthDebugSectionName, MemProt::Read);
     MachOContainerBlock = &G.createMutableContentBlock(
         SDOSec, G.allocateBuffer(DebugObjectSize), orc::ExecutorAddr(), 8, 0);
 

llvm/tools/lli/CMakeLists.txt

@@ -12,8 +12,9 @@ set(LLVM_LINK_COMPONENTS
   MC
   MCJIT
   Object
-  OrcShared
   OrcJIT
+  OrcDebugging
+  OrcShared
   OrcTargetProcess
   Passes
   RuntimeDyld

llvm/tools/lli/lli.cpp

@@ -26,7 +26,7 @@
 #include "llvm/ExecutionEngine/MCJIT.h"
 #include "llvm/ExecutionEngine/ObjectCache.h"
 #include "llvm/ExecutionEngine/Orc/DebugUtils.h"
-#include "llvm/ExecutionEngine/Orc/DebuggerSupport.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupport.h"
 #include "llvm/ExecutionEngine/Orc/EPCDynamicLibrarySearchGenerator.h"
 #include "llvm/ExecutionEngine/Orc/EPCEHFrameRegistrar.h"
 #include "llvm/ExecutionEngine/Orc/EPCGenericRTDyldMemoryManager.h"

llvm/tools/llvm-jitlink/llvm-jitlink.cpp

@@ -18,8 +18,8 @@
 #include "llvm/ExecutionEngine/Orc/COFFPlatform.h"
 #include "llvm/ExecutionEngine/Orc/COFFVCRuntimeSupport.h"
 #include "llvm/ExecutionEngine/Orc/DebugObjectManagerPlugin.h"
-#include "llvm/ExecutionEngine/Orc/DebuggerSupportPlugin.h"
 #include "llvm/ExecutionEngine/Orc/Debugging/DebugInfoSupport.h"
+#include "llvm/ExecutionEngine/Orc/Debugging/DebuggerSupportPlugin.h"
 #include "llvm/ExecutionEngine/Orc/Debugging/PerfSupportPlugin.h"
 #include "llvm/ExecutionEngine/Orc/ELFNixPlatform.h"
 #include "llvm/ExecutionEngine/Orc/EPCDebugObjectRegistrar.h"