Add support for applying in-memory relocations to the .debug_line section and, in the case of ELF files, using symbol addresses when available for relocations to the .debug_info section. Also extending the llvm-rtdyld tool to add the ability to dump line number information for testing purposes.

llvm-svn: 173517

3 files changed, 63 insertions, 3 deletions

diff --git a/llvm/tools/llvm-rtdyld/CMakeLists.txt b/llvm/tools/llvm-rtdyld/CMakeLists.txt
index 17e2c3e2d5b..8d161d366da 100644
--- a/llvm/tools/llvm-rtdyld/CMakeLists.txt
+++ b/llvm/tools/llvm-rtdyld/CMakeLists.txt
@@ -1,4 +1,4 @@
-set(LLVM_LINK_COMPONENTS ${LLVM_TARGETS_TO_BUILD} support MC object RuntimeDyld JIT)
+set(LLVM_LINK_COMPONENTS ${LLVM_TARGETS_TO_BUILD} support MC object RuntimeDyld JIT debuginfo)
 
 add_llvm_tool(llvm-rtdyld
   llvm-rtdyld.cpp
diff --git a/llvm/tools/llvm-rtdyld/Makefile b/llvm/tools/llvm-rtdyld/Makefile
index 30fbee0979b..fabdd683a99 100644
--- a/llvm/tools/llvm-rtdyld/Makefile
+++ b/llvm/tools/llvm-rtdyld/Makefile
@@ -9,7 +9,7 @@
 
 LEVEL := ../..
 TOOLNAME := llvm-rtdyld
-LINK_COMPONENTS := all-targets support MC object RuntimeDyld JIT
+LINK_COMPONENTS := all-targets support MC object RuntimeDyld JIT debuginfo
 
 # This tool has no plugins, optimize startup time.
 TOOL_NO_EXPORTS := 1
diff --git a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
index ec63c9b56ca..8b71a4f3641 100644
--- a/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
+++ b/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp
@@ -13,6 +13,7 @@
 
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/ADT/StringMap.h"
+#include "llvm/DebugInfo/DIContext.h"
 #include "llvm/ExecutionEngine/ObjectBuffer.h"
 #include "llvm/ExecutionEngine/ObjectImage.h"
 #include "llvm/ExecutionEngine/RuntimeDyld.h"
@@ -31,7 +32,8 @@ InputFileList(cl::Positional, cl::ZeroOrMore,
               cl::desc("<input file>"));
 
 enum ActionType {
-  AC_Execute
+  AC_Execute,
+  AC_PrintLineInfo
 };
 
 static cl::opt<ActionType>
@@ -39,6 +41,8 @@ Action(cl::desc("Action to perform:"),
        cl::init(AC_Execute),
        cl::values(clEnumValN(AC_Execute, "execute",
                              "Load, link, and execute the inputs."),
+                  clEnumValN(AC_PrintLineInfo, "printline",
+                             "Load, link, and print line information for each function."),
                   clEnumValEnd));
 
 static cl::opt<std::string>
@@ -114,6 +118,60 @@ static int Error(const Twine &Msg) {
 
 /* *** */
 
+static int printLineInfoForInput() {
+  // If we don't have any input files, read from stdin.
+  if (!InputFileList.size())
+    InputFileList.push_back("-");
+  for(unsigned i = 0, e = InputFileList.size(); i != e; ++i) {
+    // Instantiate a dynamic linker.
+    TrivialMemoryManager *MemMgr = new TrivialMemoryManager;
+    RuntimeDyld Dyld(MemMgr);
+
+    // Load the input memory buffer.
+    OwningPtr<MemoryBuffer> InputBuffer;
+    OwningPtr<ObjectImage>  LoadedObject;
+    if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFileList[i],
+                                                     InputBuffer))
+      return Error("unable to read input: '" + ec.message() + "'");
+
+    // Load the object file
+    LoadedObject.reset(Dyld.loadObject(new ObjectBuffer(InputBuffer.take())));
+    if (!LoadedObject) {
+      return Error(Dyld.getErrorString());
+    }
+
+    // Resolve all the relocations we can.
+    Dyld.resolveRelocations();
+
+    OwningPtr<DIContext> Context(DIContext::getDWARFContext(LoadedObject->getObjectFile()));
+
+    // Use symbol info to iterate functions in the object.
+    error_code ec;
+    for (object::symbol_iterator I = LoadedObject->begin_symbols(),
+                                 E = LoadedObject->end_symbols();
+                          I != E && !ec;
+                          I.increment(ec)) {
+      object::SymbolRef::Type SymType;
+      if (I->getType(SymType)) continue;
+      if (SymType == object::SymbolRef::ST_Function) {
+        StringRef  Name;
+        uint64_t   Addr;
+        uint64_t   Size;
+        if (I->getName(Name)) continue;
+        if (I->getAddress(Addr)) continue;
+        if (I->getSize(Size)) continue;
+
+        outs() << "Function: " << Name << ", Size = " << Size << "\n";
+
+        DILineInfo Result = Context->getLineInfoForAddress(Addr);
+        outs() << "  Line info:" << Result.getFileName() << ", line:" << Result.getLine() << "\n";
+      }
+    }
+  }
+
+  return 0;
+}
+
 static int executeInput() {
   // Instantiate a dynamic linker.
   TrivialMemoryManager *MemMgr = new TrivialMemoryManager;
@@ -180,5 +238,7 @@ int main(int argc, char **argv) {
   switch (Action) {
   case AC_Execute:
     return executeInput();
+  case AC_PrintLineInfo:
+    return printLineInfoForInput();
   }
 }