[llvm] r295765 - Don't modify archive members unless really needed.
Rafael Espindola via llvm-commits
llvm-commits at lists.llvm.org
Tue Feb 21 12:40:54 PST 2017
Author: rafael
Date: Tue Feb 21 14:40:54 2017
New Revision: 295765
URL: http://llvm.org/viewvc/llvm-project?rev=295765&view=rev
Log:
Don't modify archive members unless really needed.
For whatever reason ld64 requires that member headers (not the member
themselves) should be aligned. The only way to do that is to edit the
previous member so that it ends at an aligned boundary.
Since modifying data put in an archive is an undesirable property,
llvm-ar should only do it when it is absolutely necessary.
Added:
llvm/trunk/test/Object/archive-pad.test
Modified:
llvm/trunk/include/llvm/Object/Archive.h
llvm/trunk/lib/Object/ArchiveWriter.cpp
llvm/trunk/test/Object/archive-extract.test
llvm/trunk/test/Object/archive-format.test
llvm/trunk/tools/llvm-ar/llvm-ar.cpp
Modified: llvm/trunk/include/llvm/Object/Archive.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/Archive.h?rev=295765&r1=295764&r2=295765&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/Archive.h (original)
+++ llvm/trunk/include/llvm/Object/Archive.h Tue Feb 21 14:40:54 2017
@@ -212,6 +212,7 @@ public:
K_GNU,
K_MIPS64,
K_BSD,
+ K_DARWIN,
K_DARWIN64,
K_COFF
};
Modified: llvm/trunk/lib/Object/ArchiveWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/ArchiveWriter.cpp?rev=295765&r1=295764&r2=295765&view=diff
==============================================================================
--- llvm/trunk/lib/Object/ArchiveWriter.cpp (original)
+++ llvm/trunk/lib/Object/ArchiveWriter.cpp Tue Feb 21 14:40:54 2017
@@ -122,12 +122,26 @@ static void printWithSpacePadding(raw_fd
}
}
+static bool isBSDLike(object::Archive::Kind Kind) {
+ switch (Kind) {
+ case object::Archive::K_GNU:
+ return false;
+ case object::Archive::K_BSD:
+ case object::Archive::K_DARWIN:
+ return true;
+ case object::Archive::K_MIPS64:
+ case object::Archive::K_DARWIN64:
+ case object::Archive::K_COFF:
+ llvm_unreachable("not supported for writting");
+ }
+}
+
static void print32(raw_ostream &Out, object::Archive::Kind Kind,
uint32_t Val) {
- if (Kind == object::Archive::K_GNU)
- support::endian::Writer<support::big>(Out).write(Val);
- else
+ if (isBSDLike(Kind))
support::endian::Writer<support::little>(Out).write(Val);
+ else
+ support::endian::Writer<support::big>(Out).write(Val);
}
static void printRestOfMemberHeader(
@@ -178,7 +192,7 @@ printMemberHeader(raw_fd_ostream &Out, o
std::vector<unsigned>::iterator &StringMapIndexIter,
const sys::TimePoint<std::chrono::seconds> &ModTime,
unsigned UID, unsigned GID, unsigned Perms, unsigned Size) {
- if (Kind == object::Archive::K_BSD)
+ if (isBSDLike(Kind))
return printBSDMemberHeader(Out, Name, ModTime, UID, GID, Perms, Size);
if (!useStringTable(Thin, Name))
return printGNUSmallMemberHeader(Out, Name, ModTime, UID, GID, Perms, Size);
@@ -285,10 +299,10 @@ writeSymbolTable(raw_fd_ostream &Out, ob
if (!HeaderStartOffset) {
HeaderStartOffset = Out.tell();
- if (Kind == object::Archive::K_GNU)
- printGNUSmallMemberHeader(Out, "", now(Deterministic), 0, 0, 0, 0);
- else
+ if (isBSDLike(Kind))
printBSDMemberHeader(Out, "__.SYMDEF", now(Deterministic), 0, 0, 0, 0);
+ else
+ printGNUSmallMemberHeader(Out, "", now(Deterministic), 0, 0, 0, 0);
BodyStartOffset = Out.tell();
print32(Out, Kind, 0); // number of entries or bytes
}
@@ -307,7 +321,7 @@ writeSymbolTable(raw_fd_ostream &Out, ob
return EC;
NameOS << '\0';
MemberOffsetRefs.push_back(MemberNum);
- if (Kind == object::Archive::K_BSD)
+ if (isBSDLike(Kind))
print32(Out, Kind, NameOffset);
print32(Out, Kind, 0); // member offset
}
@@ -318,12 +332,12 @@ writeSymbolTable(raw_fd_ostream &Out, ob
// ld64 prefers the cctools type archive which pads its string table to a
// boundary of sizeof(int32_t).
- if (Kind == object::Archive::K_BSD)
+ if (isBSDLike(Kind))
for (unsigned P = OffsetToAlignment(NameOS.tell(), sizeof(int32_t)); P--;)
NameOS << '\0';
StringRef StringTable = NameOS.str();
- if (Kind == object::Archive::K_BSD)
+ if (isBSDLike(Kind))
print32(Out, Kind, StringTable.size()); // byte count of the string table
Out << StringTable;
@@ -342,10 +356,10 @@ writeSymbolTable(raw_fd_ostream &Out, ob
// Patch up the number of symbols.
Out.seek(BodyStartOffset);
unsigned NumSyms = MemberOffsetRefs.size();
- if (Kind == object::Archive::K_GNU)
- print32(Out, Kind, NumSyms);
- else
+ if (isBSDLike(Kind))
print32(Out, Kind, NumSyms * 8);
+ else
+ print32(Out, Kind, NumSyms);
Out.seek(Pos);
return BodyStartOffset + 4;
@@ -357,8 +371,7 @@ llvm::writeArchive(StringRef ArcName,
bool WriteSymtab, object::Archive::Kind Kind,
bool Deterministic, bool Thin,
std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
- assert((!Thin || Kind == object::Archive::K_GNU) &&
- "Only the gnu format has a thin mode");
+ assert((!Thin || !isBSDLike(Kind)) && "Only the gnu format has a thin mode");
SmallString<128> TmpArchive;
int TmpArchiveFD;
if (auto EC = sys::fs::createUniqueFile(ArcName + ".temp-archive-%%%%%%%.a",
@@ -388,7 +401,7 @@ llvm::writeArchive(StringRef ArcName,
}
std::vector<unsigned> StringMapIndexes;
- if (Kind != object::Archive::K_BSD)
+ if (!isBSDLike(Kind))
writeStringTable(Out, ArcName, NewMembers, StringMapIndexes, Thin);
std::vector<unsigned>::iterator StringMapIndexIter = StringMapIndexes.begin();
@@ -404,7 +417,7 @@ llvm::writeArchive(StringRef ArcName,
// least 4-byte aligned for 32-bit content. Opt for the larger encoding
// uniformly. This matches the behaviour with cctools and ensures that ld64
// is happy with archives that we generate.
- if (Kind == object::Archive::K_BSD)
+ if (Kind == object::Archive::K_DARWIN)
Padding = OffsetToAlignment(M.Buf->getBufferSize(), 8);
printMemberHeader(Out, Kind, Thin,
@@ -424,7 +437,7 @@ llvm::writeArchive(StringRef ArcName,
if (MemberReferenceOffset) {
Out.seek(MemberReferenceOffset);
for (unsigned MemberNum : MemberOffsetRefs) {
- if (Kind == object::Archive::K_BSD)
+ if (isBSDLike(Kind))
Out.seek(Out.tell() + 4); // skip over the string offset
print32(Out, Kind, MemberOffset[MemberNum]);
}
Modified: llvm/trunk/test/Object/archive-extract.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/archive-extract.test?rev=295765&r1=295764&r2=295765&view=diff
==============================================================================
--- llvm/trunk/test/Object/archive-extract.test (original)
+++ llvm/trunk/test/Object/archive-extract.test Tue Feb 21 14:40:54 2017
@@ -43,10 +43,10 @@
CHECK-GNU: 1465 2004-11-19 03:01:31.000000000 very_long_bytecode_file_name.bc
; RUN: rm -f %t.a
-; RUN: llvm-ar -format bsd rcU %t.a very_long_bytecode_file_name.bc
-; RUN: env TZ=GMT llvm-ar tv %t.a | FileCheck %s -check-prefix CHECK-BSD
+; RUN: llvm-ar -format darwin rcU %t.a very_long_bytecode_file_name.bc
+; RUN: env TZ=GMT llvm-ar tv %t.a | FileCheck %s -check-prefix CHECK-DARWIN
-CHECK-BSD: 1472 2004-11-19 03:01:31.000000000 very_long_bytecode_file_name.bc
+CHECK-DARWIN: 1472 2004-11-19 03:01:31.000000000 very_long_bytecode_file_name.bc
RUN: not llvm-ar x %p/Inputs/GNU.a foo.o 2>&1 | FileCheck --check-prefix=NOTFOUND %s
NOTFOUND: foo.o was not found
Modified: llvm/trunk/test/Object/archive-format.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/archive-format.test?rev=295765&r1=295764&r2=295765&view=diff
==============================================================================
--- llvm/trunk/test/Object/archive-format.test (original)
+++ llvm/trunk/test/Object/archive-format.test Tue Feb 21 14:40:54 2017
@@ -32,12 +32,23 @@ RUN: llvm-ar --format=bsd rc %t.a 012345
RUN: cat %t.a | FileCheck -strict-whitespace --check-prefix=BSD %s
BSD: !<arch>
-BSD-NEXT: #1/20 0 0 0 644 28 `
+BSD-NEXT: #1/20 0 0 0 644 24 `
+BSD-NEXT: 0123456789abcde{{.....}}bar.
+BSD-SAME: #1/16 0 0 0 644 20 `
+BSD-NEXT: 0123456789abcdefzed.
+
+RUN: rm -f %t.a
+RUN: llvm-ar --format=darwin rc %t.a 0123456789abcde 0123456789abcdef
+RUN: cat %t.a | FileCheck -strict-whitespace --check-prefix=DARWIN %s
+
+DARWIN: !<arch>
+DARWIN-NEXT: #1/20 0 0 0 644 28 `
Each [[:space:]] matches a newline. We explicitly match 3 newlines, as the
fourth newline is implicitly consumed by FileCheck and cannot be matched.
-BSD-NEXT: 0123456789abcde{{.....}}bar.{{[[:space:]][[:space:]][[:space:]]}}
-BSD-NEXT: #1/20 0 0 0 644 28 `
-BSD-NEXT: 0123456789abcdef{{....}}zed.
+DARWIN-NEXT: 0123456789abcde{{.....}}bar.{{[[:space:]][[:space:]][[:space:]]}}
+DARWIN-NEXT: #1/20 0 0 0 644 28 `
+DARWIN-NEXT: 0123456789abcdef{{....}}zed.
+
RUN: rm -f test.a
RUN: llvm-ar --format=gnu rcT test.a 0123456789abcde 0123456789abcdef
Added: llvm/trunk/test/Object/archive-pad.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/archive-pad.test?rev=295765&view=auto
==============================================================================
--- llvm/trunk/test/Object/archive-pad.test (added)
+++ llvm/trunk/test/Object/archive-pad.test Tue Feb 21 14:40:54 2017
@@ -0,0 +1,19 @@
+Test that only the darwin format needs to modify archive members to
+avoid a ld64 bug.
+
+RUN: echo foo > %t.o
+
+RUN: rm -f %t.a
+RUN: llvm-ar -format=bsd rc %t.a %t.o
+RUN: llvm-ar p %t.a > %bsd.o
+RUN: cmp %bsd.o %t.o
+
+RUN: rm -f %t.a
+RUN: llvm-ar -format=gnu rc %t.a %t.o
+RUN: llvm-ar p %t.a > %gnu.o
+RUN: cmp %gnu.o %t.o
+
+RUN: rm -f %t.a
+RUN: llvm-ar -format=darwin rc %t.a %t.o
+RUN: llvm-ar p %t.a > %darwin.o
+RUN: not cmp %darwin.o %t.o
Modified: llvm/trunk/tools/llvm-ar/llvm-ar.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-ar/llvm-ar.cpp?rev=295765&r1=295764&r2=295765&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-ar/llvm-ar.cpp (original)
+++ llvm/trunk/tools/llvm-ar/llvm-ar.cpp Tue Feb 21 14:40:54 2017
@@ -87,13 +87,14 @@ static cl::opt<bool> MRI("M", cl::desc("
static cl::opt<std::string> Plugin("plugin", cl::desc("plugin (ignored for compatibility"));
namespace {
-enum Format { Default, GNU, BSD };
+enum Format { Default, GNU, BSD, DARWIN };
}
static cl::opt<Format>
FormatOpt("format", cl::desc("Archive format to create"),
cl::values(clEnumValN(Default, "default", "default"),
clEnumValN(GNU, "gnu", "gnu"),
+ clEnumValN(DARWIN, "darwin", "darwin"),
clEnumValN(BSD, "bsd", "bsd")));
static std::string Options;
@@ -623,8 +624,9 @@ computeNewArchiveMembers(ArchiveOperatio
}
static object::Archive::Kind getDefaultForHost() {
- return Triple(sys::getProcessTriple()).isOSDarwin() ? object::Archive::K_BSD
- : object::Archive::K_GNU;
+ return Triple(sys::getProcessTriple()).isOSDarwin()
+ ? object::Archive::K_DARWIN
+ : object::Archive::K_GNU;
}
static object::Archive::Kind getKindFromMember(const NewArchiveMember &Member) {
@@ -633,7 +635,7 @@ static object::Archive::Kind getKindFrom
if (OptionalObject)
return isa<object::MachOObjectFile>(**OptionalObject)
- ? object::Archive::K_BSD
+ ? object::Archive::K_DARWIN
: object::Archive::K_GNU;
// squelch the error in case we had a non-object file
@@ -672,6 +674,11 @@ performWriteOperation(ArchiveOperation O
fail("Only the gnu format has a thin mode");
Kind = object::Archive::K_BSD;
break;
+ case DARWIN:
+ if (Thin)
+ fail("Only the gnu format has a thin mode");
+ Kind = object::Archive::K_DARWIN;
+ break;
}
std::pair<StringRef, std::error_code> Result =
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