[lld] r223524 - [PECOFF] Fix exported symbols in an import library.

[Rui Ueyama]

Author: ruiu
Date: Fri Dec  5 15:52:02 2014
New Revision: 223524

URL: http://llvm.org/viewvc/llvm-project?rev=223524&view=rev
Log:
[PECOFF] Fix exported symbols in an import library.

Looks like if you have symbol foo in a module-definition file
(.def file), and if the actual symbol name to match that export
description is _foo at x (where x is an integer), the exported
symbol name becomes this.

  - foo in the .dll file
  - foo at x in the .lib file

I have checked in a few fixes recently for exported symbol name mangling.
I haven't found a simple rule that governs all the mangling rules.
There may not ever exist. For now, this is a patch to improve .lib
file compatibility.

Added:
    lld/trunk/test/pecoff/Inputs/exports2.def
Modified:
    lld/trunk/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp
    lld/trunk/test/pecoff/exportlib2.test

Modified: lld/trunk/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp?rev=223524&r1=223523&r2=223524&view=diff
==============================================================================
--- lld/trunk/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp (original)
+++ lld/trunk/lib/ReaderWriter/PECOFF/WriterImportLibrary.cpp Fri Dec  5 15:52:02 2014
@@ -35,6 +35,8 @@ createModuleDefinitionFile(const PECOFFL
     os << "  ";
     if (!desc.externalName.empty()) {
       os << desc.externalName;
+    } else if (!desc.mangledName.empty()) {
+      os << ctx.undecorateSymbol(desc.mangledName);
     } else {
       os << ctx.undecorateSymbol(desc.name);
     }

Added: lld/trunk/test/pecoff/Inputs/exports2.def
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/pecoff/Inputs/exports2.def?rev=223524&view=auto
==============================================================================
--- lld/trunk/test/pecoff/Inputs/exports2.def (added)
+++ lld/trunk/test/pecoff/Inputs/exports2.def Fri Dec  5 15:52:02 2014
@@ -0,0 +1,6 @@
+; This is a comment line
+
+EXPORTS
+  exportfn1 @5   ; foo
+  exportfn7
+  exportfn5=exportfn6 PRIVATE

Modified: lld/trunk/test/pecoff/exportlib2.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/pecoff/exportlib2.test?rev=223524&r1=223523&r2=223524&view=diff
==============================================================================
--- lld/trunk/test/pecoff/exportlib2.test (original)
+++ lld/trunk/test/pecoff/exportlib2.test Fri Dec  5 15:52:02 2014
@@ -1,8 +1,8 @@
 # RUN: yaml2obj %p/Inputs/export.obj.yaml > %t.obj
 #
 # RUN: lld -flavor link /out:%t.dll /dll /entry:init \
-# RUN:   /export:exportfn1 /export:exportfn2 /lldmoduledeffile:%t.def -- %t.obj
-# RUN: FileCheck -check-prefix=CHECK1 %s < %t.def
+# RUN:   /export:exportfn1 /export:exportfn2 /lldmoduledeffile:%t1.def -- %t.obj
+# RUN: FileCheck -check-prefix=CHECK1 %s < %t1.def
 
 CHECK1: LIBRARY "exportlib2.test.tmp.dll"
 CHECK1: EXPORTS
@@ -11,11 +11,11 @@ CHECK1:   exportfn2 @2
 CHECK1:   exportfn3 at 256 @3
 
 # RUN: lld -flavor link /out:%t.dll /dll /entry:init \
-# RUN:   /def:%p/Inputs/exports.def /lldmoduledeffile:%t.def -- %t.obj
-# RUN: FileCheck -check-prefix=CHECK2 %s < %t.def
+# RUN:   /def:%p/Inputs/exports2.def /lldmoduledeffile:%t2.def -- %t.obj
+# RUN: FileCheck -check-prefix=CHECK2 %s < %t2.def
 
 CHECK2: LIBRARY "exportlib2.test.tmp.dll"
 CHECK2: EXPORTS
 CHECK2:   exportfn1 @5
-CHECK2:   exportfn2 @6
-CHECK2:   exportfn3 at 256 @7
+CHECK2:   exportfn3 at 256 @6
+CHECK2:   exportfn7 at 8 @7