lld-link: Only print demangled symbol names by default

This makes lld-link's output a bit more concise. Since most developers can't read mangled names, this should make the output a bit easier to understand as well. It also makes lld-link's output consistent with ld.lld's output. (link.exe prints both demangled and mangled names; lld-link used to match link.exe output but now no longer does.) For people working on toolchains, add a `/demangle:no` flag that makes lld-link print the mangled name instead of the demangled name. (If desired, people could pipe that through `demumble -b` to get the old behavior of both demangled and mangled output.) Differential Revision: https://reviews.llvm.org/D58132 llvm-svn: 355878
llvm · Mar 11, 2019 · 020d92c · 020d92c
1 parent 86af6f5
commit 020d92c
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Showing 6 changed files with 24 additions and 13 deletions.
diff --git a/lld/COFF/Config.h b/lld/COFF/Config.h
@@ -90,6 +90,7 @@ struct Configuration {
   bool NoEntry = false;
   std::string OutputFile;
   std::string ImportName;
+  bool Demangle = true;
   bool DoGC = true;
   bool DoICF = true;
   bool TailMerge;

diff --git a/lld/COFF/Driver.cpp b/lld/COFF/Driver.cpp
@@ -1081,6 +1081,9 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
     Config->Incremental = true;
   }
 
+  // Handle /demangle
+  Config->Demangle = Args.hasFlag(OPT_demangle, OPT_demangle_no);
+
   // Handle /debugtype
   Config->DebugTypes = parseDebugTypes(Args);
 

diff --git a/lld/COFF/Options.td b/lld/COFF/Options.td
@@ -154,6 +154,9 @@ def help_q : Flag<["/?", "-?"], "">, Alias<help>;
 // LLD extensions
 def exclude_all_symbols : F<"exclude-all-symbols">;
 def export_all_symbols : F<"export-all-symbols">;
+defm demangle : B<"demangle",
+    "Demangle symbols in output (default)",
+    "Do not demangle symbols in output">;
 def kill_at : F<"kill-at">;
 def lldmingw : F<"lldmingw">;
 def output_def : Joined<["/", "-"], "output-def:">;
@@ -178,11 +181,6 @@ def show_timing : F<"time">;
 
 class QF<string name> : Joined<["/", "-", "-?"], name#":">;
 
-multiclass QB<string name> {
-  def "" : F<name>;
-  def _no : F<name#":no">;
-}
-
 def ignoreidl : F<"ignoreidl">;
 def nologo : F<"nologo">;
 def throwingnew : F<"throwingnew">;

diff --git a/lld/COFF/Symbols.cpp b/lld/COFF/Symbols.cpp
@@ -18,10 +18,13 @@
 using namespace llvm;
 using namespace llvm::object;
 
+using namespace lld::coff;
+
 // Returns a symbol name for an error message.
 std::string lld::toString(coff::Symbol &B) {
-  if (Optional<std::string> S = lld::demangleMSVC(B.getName()))
-    return ("\"" + *S + "\" (" + B.getName() + ")").str();
+  if (Config->Demangle)
+    if (Optional<std::string> S = lld::demangleMSVC(B.getName()))
+      return *S;
   return B.getName();
 }
 

diff --git a/lld/test/COFF/undefined-symbol-cv.s b/lld/test/COFF/undefined-symbol-cv.s
@@ -2,19 +2,19 @@
 # RUN: llvm-mc -triple=x86_64-windows-msvc -filetype=obj -o %t.obj %s
 # RUN: not lld-link /out:%t.exe %t.obj 2>&1 | FileCheck %s
 
-# CHECK: error: undefined symbol: "int __cdecl foo(void)" (?foo@@YAHXZ)
+# CHECK: error: undefined symbol: int __cdecl foo(void)
 # CHECK-NEXT: >>> referenced by file1.cpp:1
 # CHECK-NEXT: >>>               {{.*}}.obj:(main)
 # CHECK-NEXT: >>> referenced by file1.cpp:2
 # CHECK-NEXT: >>>               {{.*}}.obj:(main)
 # CHECK-EMPTY:
-# CHECK-NEXT: error: undefined symbol: "int __cdecl bar(void)" (?bar@@YAHXZ)
+# CHECK-NEXT: error: undefined symbol: int __cdecl bar(void)
 # CHECK-NEXT: >>> referenced by file2.cpp:3
 # CHECK-NEXT: >>>               {{.*}}.obj:(main)
 # CHECK-NEXT: >>> referenced by file1.cpp:4
 # CHECK-NEXT: >>>               {{.*}}.obj:(f1)
 # CHECK-EMPTY:
-# CHECK-NEXT: error: undefined symbol: "int __cdecl baz(void)" (?baz@@YAHXZ)
+# CHECK-NEXT: error: undefined symbol: int __cdecl baz(void)
 # CHECK-NEXT: >>> referenced by file1.cpp:5
 # CHECK-NEXT: >>>               {{.*}}.obj:(f2)
 

diff --git a/lld/test/COFF/undefined-symbol.s b/lld/test/COFF/undefined-symbol.s
@@ -1,16 +1,22 @@
 # REQUIRES: x86
 # RUN: llvm-mc -triple=x86_64-windows-msvc -filetype=obj -o %t.obj %s
 # RUN: not lld-link /out:%t.exe %t.obj 2>&1 | FileCheck %s
+# RUN: not lld-link /out:%t.exe /demangle %t.obj 2>&1 | FileCheck %s
+# RUN: not lld-link /out:%t.exe /demangle:no %t.obj 2>&1 | FileCheck --check-prefix=NODEMANGLE %s
 
-# CHECK: error: undefined symbol: "int __cdecl foo(void)" (?foo@@YAHXZ)
+# NODEMANGLE: error: undefined symbol: ?foo@@YAHXZ
+# NODEMANGLE: error: undefined symbol: ?bar@@YAHXZ
+# NODEMANGLE: error: undefined symbol: __imp_?baz@@YAHXZ
+
+# CHECK: error: undefined symbol: int __cdecl foo(void)
 # CHECK-NEXT: >>> referenced by {{.*}}.obj:(main)
 # CHECK-NEXT: >>> referenced by {{.*}}.obj:(main)
 # CHECK-EMPTY:
-# CHECK-NEXT: error: undefined symbol: "int __cdecl bar(void)" (?bar@@YAHXZ)
+# CHECK-NEXT: error: undefined symbol: int __cdecl bar(void)
 # CHECK-NEXT: >>> referenced by {{.*}}.obj:(main)
 # CHECK-NEXT: >>> referenced by {{.*}}.obj:(f1)
 # CHECK-EMPTY:
-# CHECK-NEXT: error: undefined symbol: "__declspec(dllimport) int __cdecl baz(void)" (__imp_?baz@@YAHXZ)
+# CHECK-NEXT: error: undefined symbol: __declspec(dllimport) int __cdecl baz(void)
 # CHECK-NEXT: >>> referenced by {{.*}}.obj:(f2)
 
         .section        .text,"xr",one_only,main