From 3a7905b2aac4931b1981193bf99ca915fe474139 Mon Sep 17 00:00:00 2001
From: Martin Storsjo <martin@martin.st>
Date: Fri, 29 Jun 2018 06:08:25 +0000
Subject: [PATCH] [COFF] Add an LLD specific option -debug:symbtab

With this set, we retain the symbol table, but skip the actual debug
information.

This is meant to be used by the MinGW frontend.

Differential Revision: https://reviews.llvm.org/D48745

llvm-svn: 335946
---
 lld/COFF/Config.h             |  1 +
 lld/COFF/Driver.cpp           |  1 +
 lld/COFF/Options.td           |  1 +
 lld/COFF/Writer.cpp           |  2 +-
 lld/test/COFF/sort-debug.test | 13 +++++++++++++
 lld/test/COFF/symtab.test     |  2 ++
 6 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/lld/COFF/Config.h b/lld/COFF/Config.h
index 3ccccb6..43dc758 100644
--- a/lld/COFF/Config.h
+++ b/lld/COFF/Config.h
@@ -98,6 +98,7 @@ struct Configuration {
   bool Debug = false;
   bool DebugDwarf = false;
   bool DebugGHashes = false;
+  bool DebugSymtab = false;
   bool ShowTiming = false;
   unsigned DebugTypes = static_cast<unsigned>(DebugType::None);
   std::vector<std::string> NatvisFiles;
diff --git a/lld/COFF/Driver.cpp b/lld/COFF/Driver.cpp
index ecfa258b..b6019ff 100644
--- a/lld/COFF/Driver.cpp
+++ b/lld/COFF/Driver.cpp
@@ -1217,6 +1217,7 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
       !Config->DLL && Args.hasFlag(OPT_tsaware, OPT_tsaware_no, true);
   Config->DebugDwarf = Args.hasArg(OPT_debug_dwarf);
   Config->DebugGHashes = Args.hasArg(OPT_debug_ghash);
+  Config->DebugSymtab = Args.hasArg(OPT_debug_symtab);
 
   Config->MapFile = getMapFile(Args);
 
diff --git a/lld/COFF/Options.td b/lld/COFF/Options.td
index 9051b0b..83aa890f 100644
--- a/lld/COFF/Options.td
+++ b/lld/COFF/Options.td
@@ -139,6 +139,7 @@ def help_q : Flag<["/?", "-?"], "">, Alias<help>;
 // LLD extensions
 def debug_ghash : F<"debug:ghash">;
 def debug_dwarf : F<"debug:dwarf">;
+def debug_symtab : F<"debug:symtab">;
 def export_all_symbols : F<"export-all-symbols">;
 def kill_at : F<"kill-at">;
 def lldmingw : F<"lldmingw">;
diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp
index a9950e4..c6e17ee 100644
--- a/lld/COFF/Writer.cpp
+++ b/lld/COFF/Writer.cpp
@@ -665,7 +665,7 @@ void Writer::createSymbolAndStringTable() {
     Sec->setStringTableOff(addEntryToStringTable(Sec->Name));
   }
 
-  if (Config->DebugDwarf) {
+  if (Config->DebugDwarf || Config->DebugSymtab) {
     for (ObjFile *File : ObjFile::Instances) {
       for (Symbol *B : File->getSymbols()) {
         auto *D = dyn_cast_or_null<Defined>(B);
diff --git a/lld/test/COFF/sort-debug.test b/lld/test/COFF/sort-debug.test
index 3bad013..e11b8b4 100644
--- a/lld/test/COFF/sort-debug.test
+++ b/lld/test/COFF/sort-debug.test
@@ -1,6 +1,12 @@
 # RUN: yaml2obj < %s > %t.obj
 # RUN: lld-link /debug /out:%t.exe /entry:main %t.obj
 # RUN: llvm-readobj -sections %t.exe | FileCheck %s
+# RUN: lld-link /debug:dwarf /out:%t.exe /entry:main %t.obj
+# RUN: llvm-readobj -sections %t.exe | FileCheck %s
+# RUN: lld-link /out:%t.exe /entry:main %t.obj
+# RUN: llvm-readobj -sections %t.exe | FileCheck -check-prefix=NODEBUG %s
+# RUN: lld-link /debug:symtab /out:%t.exe /entry:main %t.obj
+# RUN: llvm-readobj -sections %t.exe | FileCheck -check-prefix=NODEBUG %s
 
 # CHECK: Name: .text
 # CHECK: Name: .debug_abbrev
@@ -10,6 +16,13 @@
 # CHECK: Name: .debug_pubtypes
 # CHECK: Name: .reloc
 
+# NODEBUG: Name: .text
+# NODEBUG-NOT: Name: .debug_abbrev
+# NODEBUG-NOT: Name: .debug_info
+# NODEBUG-NOT: Name: .debug_line
+# NODEBUG-NOT: Name: .debug_pubnames
+# NODEBUG-NOT: Name: .debug_pubtypes
+# NODEBUG: Name: .reloc
 
 --- !COFF
 header:
diff --git a/lld/test/COFF/symtab.test b/lld/test/COFF/symtab.test
index 49302d7..bedcd2f 100644
--- a/lld/test/COFF/symtab.test
+++ b/lld/test/COFF/symtab.test
@@ -3,6 +3,8 @@
 # RUN: llvm-readobj -symbols %t.exe | FileCheck %s
 # RUN: lld-link /debug:dwarf /opt:noref /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
 # RUN: llvm-readobj -symbols %t.exe | FileCheck %s
+# RUN: lld-link /debug:symtab /opt:noref /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
+# RUN: llvm-readobj -symbols %t.exe | FileCheck %s
 
 # RUN: lld-link /debug /out:%t.exe /entry:main %t.obj %p/Inputs/std64.lib
 # RUN: llvm-readobj -symbols %t.exe | FileCheck -check-prefix=NO %s
-- 
2.7.4