[lld] r298942 - COFF: include archive name in LTO object name

[Bob Haarman via llvm-commits]

Author: inglorion
Date: Tue Mar 28 16:20:06 2017
New Revision: 298942

URL: http://llvm.org/viewvc/llvm-project?rev=298942&view=rev
Log:
COFF: include archive name in LTO object name

Summary: In the ELF linker, we create the buffer identifier for bitcode files by appending the object name to the archive name. This change makes the COFF linker do the same. Without the change, ThinLTO builds can fail with an error message about multiple ThinLTO modules per object file, caused by object files contained in different archives having the same name.

Reviewers: pcc, ruiu

Reviewed By: pcc

Subscribers: mehdi_amini

Differential Revision: https://reviews.llvm.org/D31402

Added:
    lld/trunk/test/COFF/Inputs/bar.ll
    lld/trunk/test/COFF/thinlto-archives.ll
    lld/trunk/test/ELF/lto/archive-no-index.ll
Modified:
    lld/trunk/COFF/InputFiles.cpp

Modified: lld/trunk/COFF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/InputFiles.cpp?rev=298942&r1=298941&r2=298942&view=diff
==============================================================================
--- lld/trunk/COFF/InputFiles.cpp (original)
+++ lld/trunk/COFF/InputFiles.cpp Tue Mar 28 16:20:06 2017
@@ -339,8 +339,8 @@ void ImportFile::parse() {
 }
 
 void BitcodeFile::parse() {
-  Obj = check(lto::InputFile::create(
-      MemoryBufferRef(MB.getBuffer(), Saver.save(MB.getBufferIdentifier()))));
+  Obj = check(lto::InputFile::create(MemoryBufferRef(
+      MB.getBuffer(), Saver.save(ParentName + MB.getBufferIdentifier()))));
   for (const lto::InputFile::Symbol &ObjSym : Obj->symbols()) {
     StringRef SymName = Saver.save(ObjSym.getName());
     auto Flags = ObjSym.getFlags();

Added: lld/trunk/test/COFF/Inputs/bar.ll
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/COFF/Inputs/bar.ll?rev=298942&view=auto
==============================================================================
--- lld/trunk/test/COFF/Inputs/bar.ll (added)
+++ lld/trunk/test/COFF/Inputs/bar.ll Tue Mar 28 16:20:06 2017
@@ -0,0 +1,6 @@
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc"
+
+define void @bar() {
+  ret void
+}

Added: lld/trunk/test/COFF/thinlto-archives.ll
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/COFF/thinlto-archives.ll?rev=298942&view=auto
==============================================================================
--- lld/trunk/test/COFF/thinlto-archives.ll (added)
+++ lld/trunk/test/COFF/thinlto-archives.ll Tue Mar 28 16:20:06 2017
@@ -0,0 +1,22 @@
+; RUN: rm -fr %T/thinlto-archives
+; RUN: mkdir %T/thinlto-archives %T/thinlto-archives/a %T/thinlto-archives/b
+; RUN: opt -thinlto-bc -o %T/thinlto-archives/main.obj %s
+; RUN: opt -thinlto-bc -o %T/thinlto-archives/a/bar.obj %S/Inputs/lto-dep.ll
+; RUN: opt -thinlto-bc -o %T/thinlto-archives/b/bar.obj %S/Inputs/bar.ll
+; RUN: llvm-ar crs %T/thinlto-archives/a.lib %T/thinlto-archives/a/bar.obj
+; RUN: llvm-ar crs %T/thinlto-archives/b.lib %T/thinlto-archives/b/bar.obj
+; RUN: lld-link /out:%T/thinlto-archives/main.exe -entry:main \
+; RUN:     -subsystem:console %T/thinlto-archives/main.obj \
+; RUN:     %T/thinlto-archives/a.lib %T/thinlto-archives/b.lib
+
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc"
+
+declare void @bar()
+declare void @foo()
+
+define i32 @main() {
+  call void @foo()
+  call void @bar()
+  ret i32 0
+}

Added: lld/trunk/test/ELF/lto/archive-no-index.ll
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/lto/archive-no-index.ll?rev=298942&view=auto
==============================================================================
--- lld/trunk/test/ELF/lto/archive-no-index.ll (added)
+++ lld/trunk/test/ELF/lto/archive-no-index.ll Tue Mar 28 16:20:06 2017
@@ -0,0 +1,39 @@
+; REQUIRES: x86
+; Tests that we suggest that LTO symbols missing from an archive index
+; may be the cause of undefined references, but only if we both
+; encountered an empty archive index and undefined references (to prevent
+; noisy false alarms).
+
+; RUN: rm -fr %T/archive-no-index
+; RUN: mkdir %T/archive-no-index
+; RUN: llvm-as %S/Inputs/archive.ll -o %T/archive-no-index/f.o
+; RUN: llvm-ar cr %T/archive-no-index/libf.a
+; RUN: llvm-ar qS %T/archive-no-index/libf.a %T/archive-no-index/f.o
+; RUN: llvm-as %s -o %t.o
+; RUN: not ld.lld -emain -m elf_x86_64 %t.o -o %t %T/archive-no-index/libf.a \
+; RUN:     2>&1 | FileCheck --check-prefix=NOTE %s
+
+; RUN: llvm-ar crs %T/archive-no-index/libfs.a %T/archive-no-index/f.o
+; RUN: ld.lld -emain -m elf_x86_64 %t.o -o %t %T/archive-no-index/libf.a \
+; RUN:     %T/archive-no-index/libfs.a
+
+; RUN: llvm-as %S/Inputs/archive-3.ll -o %T/archive-no-index/foo.o
+; RUN: llvm-ar crs %T/archive-no-index/libfoo.a %T/archive-no-index/foo.o
+; RUN: not ld.lld -emain -m elf_x86_64 %t.o -o %t %T/archive-no-index/libfoo.a \
+; RUN:     2>&1 | FileCheck --check-prefix=NO-NOTE %s
+
+; NOTE: undefined symbol 'f'
+; NOTE: archive listed no symbols
+
+; NO-NOTE: undefined symbol 'f'
+; NO-NOTE-NOT: archive listed no symbols
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare void @f()
+
+define i32 @main() {
+  call void @f()
+  ret i32 0
+}