Commit 54e470f936
Changed files (15)
deps/lld/COFF/Driver.cpp
@@ -116,6 +116,19 @@ static std::future<MBErrPair> createFutureForFile(std::string Path) {
});
}
+// Symbol names are mangled by prepending "_" on x86.
+static StringRef mangle(StringRef Sym) {
+ assert(Config->Machine != IMAGE_FILE_MACHINE_UNKNOWN);
+ if (Config->Machine == I386)
+ return Saver.save("_" + Sym);
+ return Sym;
+}
+
+static bool findUnderscoreMangle(StringRef Sym) {
+ StringRef Entry = Symtab->findMangle(mangle(Sym));
+ return !Entry.empty() && !isa<Undefined>(Symtab->find(Entry));
+}
+
MemoryBufferRef LinkerDriver::takeBuffer(std::unique_ptr<MemoryBuffer> MB) {
MemoryBufferRef MBRef = *MB;
make<std::unique_ptr<MemoryBuffer>>(std::move(MB)); // take ownership
@@ -407,54 +420,38 @@ Symbol *LinkerDriver::addUndefined(StringRef Name) {
return B;
}
-// Symbol names are mangled by appending "_" prefix on x86.
-StringRef LinkerDriver::mangle(StringRef Sym) {
- assert(Config->Machine != IMAGE_FILE_MACHINE_UNKNOWN);
- if (Config->Machine == I386)
- return Saver.save("_" + Sym);
- return Sym;
-}
-
// Windows specific -- find default entry point name.
//
// There are four different entry point functions for Windows executables,
// each of which corresponds to a user-defined "main" function. This function
// infers an entry point from a user-defined "main" function.
StringRef LinkerDriver::findDefaultEntry() {
+ assert(Config->Subsystem != IMAGE_SUBSYSTEM_UNKNOWN &&
+ "must handle /subsystem before calling this");
+
// As a special case, if /nodefaultlib is given, we directly look for an
// entry point. This is because, if no default library is linked, users
// need to define an entry point instead of a "main".
- if (Config->NoDefaultLibAll) {
- for (StringRef S : {"mainCRTStartup", "wmainCRTStartup",
- "WinMainCRTStartup", "wWinMainCRTStartup"}) {
- StringRef Entry = Symtab->findMangle(S);
- if (!Entry.empty() && !isa<Undefined>(Symtab->find(Entry)))
- return mangle(S);
- }
- return "";
- }
-
- // User-defined main functions and their corresponding entry points.
- static const char *Entries[][2] = {
- {"main", "mainCRTStartup"},
- {"wmain", "wmainCRTStartup"},
- {"WinMain", "WinMainCRTStartup"},
- {"wWinMain", "wWinMainCRTStartup"},
- };
- for (auto E : Entries) {
- StringRef Entry = Symtab->findMangle(mangle(E[0]));
- if (!Entry.empty() && !isa<Undefined>(Symtab->find(Entry)))
- return mangle(E[1]);
+ bool FindMain = !Config->NoDefaultLibAll;
+ if (Config->Subsystem == IMAGE_SUBSYSTEM_WINDOWS_GUI) {
+ if (findUnderscoreMangle(FindMain ? "WinMain" : "WinMainCRTStartup"))
+ return mangle("WinMainCRTStartup");
+ if (findUnderscoreMangle(FindMain ? "wWinMain" : "wWinMainCRTStartup"))
+ return mangle("wWinMainCRTStartup");
}
+ if (findUnderscoreMangle(FindMain ? "main" : "mainCRTStartup"))
+ return mangle("mainCRTStartup");
+ if (findUnderscoreMangle(FindMain ? "wmain" : "wmainCRTStartup"))
+ return mangle("wmainCRTStartup");
return "";
}
WindowsSubsystem LinkerDriver::inferSubsystem() {
if (Config->DLL)
return IMAGE_SUBSYSTEM_WINDOWS_GUI;
- if (Symtab->findUnderscore("main") || Symtab->findUnderscore("wmain"))
+ if (findUnderscoreMangle("main") || findUnderscoreMangle("wmain"))
return IMAGE_SUBSYSTEM_WINDOWS_CUI;
- if (Symtab->findUnderscore("WinMain") || Symtab->findUnderscore("wWinMain"))
+ if (findUnderscoreMangle("WinMain") || findUnderscoreMangle("wWinMain"))
return IMAGE_SUBSYSTEM_WINDOWS_GUI;
return IMAGE_SUBSYSTEM_UNKNOWN;
}
@@ -1335,25 +1332,6 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
error("/dynamicbase:no is not compatible with " +
machineToStr(Config->Machine));
- // Handle /entry and /dll
- if (auto *Arg = Args.getLastArg(OPT_entry)) {
- Config->Entry = addUndefined(mangle(Arg->getValue()));
- } else if (!Config->Entry && !Config->NoEntry) {
- if (Args.hasArg(OPT_dll)) {
- StringRef S = (Config->Machine == I386) ? "__DllMainCRTStartup@12"
- : "_DllMainCRTStartup";
- Config->Entry = addUndefined(S);
- } else {
- // Windows specific -- If entry point name is not given, we need to
- // infer that from user-defined entry name.
- StringRef S = findDefaultEntry();
- if (S.empty())
- fatal("entry point must be defined");
- Config->Entry = addUndefined(S);
- log("Entry name inferred: " + S);
- }
- }
-
// Handle /export
for (auto *Arg : Args.filtered(OPT_export)) {
Export E = parseExport(Arg->getValue());
@@ -1379,6 +1357,34 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
return;
}
+ // Windows specific -- if no /subsystem is given, we need to infer
+ // that from entry point name. Must happen before /entry handling,
+ // and after the early return when just writing an import library.
+ if (Config->Subsystem == IMAGE_SUBSYSTEM_UNKNOWN) {
+ Config->Subsystem = inferSubsystem();
+ if (Config->Subsystem == IMAGE_SUBSYSTEM_UNKNOWN)
+ fatal("subsystem must be defined");
+ }
+
+ // Handle /entry and /dll
+ if (auto *Arg = Args.getLastArg(OPT_entry)) {
+ Config->Entry = addUndefined(mangle(Arg->getValue()));
+ } else if (!Config->Entry && !Config->NoEntry) {
+ if (Args.hasArg(OPT_dll)) {
+ StringRef S = (Config->Machine == I386) ? "__DllMainCRTStartup@12"
+ : "_DllMainCRTStartup";
+ Config->Entry = addUndefined(S);
+ } else {
+ // Windows specific -- If entry point name is not given, we need to
+ // infer that from user-defined entry name.
+ StringRef S = findDefaultEntry();
+ if (S.empty())
+ fatal("entry point must be defined");
+ Config->Entry = addUndefined(S);
+ log("Entry name inferred: " + S);
+ }
+ }
+
// Handle /delayload
for (auto *Arg : Args.filtered(OPT_delayload)) {
Config->DelayLoads.insert(StringRef(Arg->getValue()).lower());
@@ -1491,14 +1497,6 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
if (errorCount())
return;
- // Windows specific -- if no /subsystem is given, we need to infer
- // that from entry point name.
- if (Config->Subsystem == IMAGE_SUBSYSTEM_UNKNOWN) {
- Config->Subsystem = inferSubsystem();
- if (Config->Subsystem == IMAGE_SUBSYSTEM_UNKNOWN)
- fatal("subsystem must be defined");
- }
-
// Handle /safeseh.
if (Args.hasFlag(OPT_safeseh, OPT_safeseh_no, false)) {
for (ObjFile *File : ObjFile::Instances)
deps/lld/COFF/Driver.h
@@ -103,7 +103,6 @@ private:
std::set<std::string> VisitedLibs;
Symbol *addUndefined(StringRef Sym);
- StringRef mangle(StringRef Sym);
// Windows specific -- "main" is not the only main function in Windows.
// You can choose one from these four -- {w,}{WinMain,main}.
deps/lld/docs/ReleaseNotes.rst
@@ -5,18 +5,13 @@ LLD 7.0.0 Release Notes
.. contents::
:local:
-.. warning::
- These are in-progress notes for the upcoming LLVM 7.0.0 release.
- Release notes for previous releases can be found on
- `the Download Page <http://releases.llvm.org/download.html>`_.
-
Introduction
============
This document contains the release notes for the lld linker, release 7.0.0.
Here we describe the status of lld, including major improvements
from the previous release. All lld releases may be downloaded
-from the `LLVM releases web site <http://llvm.org/releases/>`_.
+from the `LLVM releases web site <https://llvm.org/releases/>`_.
Non-comprehensive list of changes in this release
=================================================
@@ -24,7 +19,15 @@ Non-comprehensive list of changes in this release
ELF Improvements
----------------
-* Item 1.
+* lld is now able to overcome MIPS GOT entries number limitation
+ and generate multi-GOT if necessary.
+
+* lld is now able to produce MIPS position-independent executable (PIE).
+
+* Fixed MIPS TLS GOT entries for local symbols in shared libraries.
+
+* Fixed calculation of MIPS GP relative relocations
+ in case of relocatable output.
COFF Improvements
-----------------
@@ -36,8 +39,3 @@ COFF Improvements
* Added support for outputting PDB debug info for MinGW targets.
* Improved compatibility of output binaries with GNU binutils objcopy/strip.
-
-MachO Improvements
-------------------
-
-* Item 1.
deps/lld/lib/ReaderWriter/MachO/ArchHandler_x86_64.cpp
@@ -621,6 +621,7 @@ void ArchHandler_x86_64::applyFixupFinal(
// Fall into llvm_unreachable().
break;
}
+ llvm_unreachable("invalid x86_64 Reference Kind");
}
void ArchHandler_x86_64::applyFixupRelocatable(const Reference &ref,
deps/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryUtils.h
@@ -186,11 +186,10 @@ packRelocation(const Relocation &r, bool swap, bool isBigEndian) {
}
inline StringRef getString16(const char s[16]) {
- StringRef x = s;
- if ( x.size() > 16 )
- return x.substr(0, 16);
- else
- return x;
+ // The StringRef(const char *) constructor passes the const char * to
+ // strlen(), so we can't use this constructor here, because if there is no
+ // null terminator in s, then strlen() will read past the end of the array.
+ return StringRef(s, strnlen(s, 16));
}
inline void setString16(StringRef str, char s[16]) {
deps/lld/test/COFF/entry-inference3.test
@@ -1,5 +1,9 @@
-# RUN: yaml2obj < %s > %t.obj
-# RUN: not lld-link /out:%t.exe %t.obj /verbose /nodefaultlib > %t.log 2>&1
+# RUN: sed -e s/ENTRYNAME/mainCRTStartup/ %s | yaml2obj > %t.obj
+# RUN: lld-link /subsystem:console /out:%t.exe %t.obj /verbose /nodefaultlib > %t.log 2>&1
+# RUN: FileCheck %s < %t.log
+
+# RUN: sed -e s/ENTRYNAME/?mainCRTStartup@@YAHXZ/ %s | yaml2obj > %t.obj
+# RUN: lld-link /subsystem:console /out:%t.exe %t.obj /verbose /nodefaultlib > %t.log 2>&1
# RUN: FileCheck %s < %t.log
# CHECK: Entry name inferred: mainCRTStartup
@@ -26,7 +30,7 @@ symbols:
NumberOfLinenumbers: 0
CheckSum: 0
Number: 0
- - Name: mainCRTStartup
+ - Name: "ENTRYNAME"
Value: 0
SectionNumber: 1
SimpleType: IMAGE_SYM_TYPE_NULL
deps/lld/test/COFF/entry-inference332.test
@@ -0,0 +1,39 @@
+# RUN: sed -e s/ENTRYNAME/_mainCRTStartup/ %s | yaml2obj > %t.obj
+# RUN: lld-link /subsystem:console /out:%t.exe %t.obj /verbose /nodefaultlib > %t.log 2>&1
+# RUN: FileCheck %s < %t.log
+
+# RUN: sed -e s/ENTRYNAME/?mainCRTStartup@@YAHXZ/ %s | yaml2obj > %t.obj
+# RUN: lld-link /subsystem:console /out:%t.exe %t.obj /verbose /nodefaultlib > %t.log 2>&1
+# RUN: FileCheck %s < %t.log
+
+# CHECK: Entry name inferred: _mainCRTStartup
+
+--- !COFF
+header:
+ Machine: IMAGE_FILE_MACHINE_I386
+ Characteristics: []
+sections:
+ - Name: .text
+ Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+ Alignment: 4
+ SectionData: B82A000000C3
+symbols:
+ - Name: .text
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_STATIC
+ SectionDefinition:
+ Length: 6
+ NumberOfRelocations: 0
+ NumberOfLinenumbers: 0
+ CheckSum: 0
+ Number: 0
+ - Name: "ENTRYNAME"
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+...
deps/lld/test/COFF/entry-inference4.test
@@ -0,0 +1,56 @@
+# RUN: sed 's/ENTRY1/WinMain/;s/ENTRY2/main/' %s | yaml2obj > %t.obj
+# RUN: not lld-link /subsystem:windows /out:%t.exe %t.obj > %t.log 2>&1
+# RUN: FileCheck -check-prefix=WINMAIN %s < %t.log
+
+# RUN: sed 's/ENTRY1/wWinMain/;s/ENTRY2/main/' %s | yaml2obj > %t.obj
+# RUN: not lld-link /subsystem:windows /out:%t.exe %t.obj > %t.log 2>&1
+# RUN: FileCheck -check-prefix=WWINMAIN %s < %t.log
+
+# RUN: sed 's/ENTRY1/WinMain/;s/ENTRY2/main/' %s | yaml2obj > %t.obj
+# RUN: not lld-link /subsystem:console /out:%t.exe %t.obj > %t.log 2>&1
+# RUN: FileCheck -check-prefix=MAIN %s < %t.log
+
+# RUN: sed 's/ENTRY1/WinMain/;s/ENTRY2/wmain/' %s | yaml2obj > %t.obj
+# RUN: not lld-link /subsystem:console /out:%t.exe %t.obj > %t.log 2>&1
+# RUN: FileCheck -check-prefix=WMAIN %s < %t.log
+
+# MAIN: error: <root>: undefined symbol: mainCRTStartup
+# WMAIN: error: <root>: undefined symbol: wmainCRTStartup
+# WINMAIN: error: <root>: undefined symbol: WinMainCRTStartup
+# WWINMAIN: error: <root>: undefined symbol: wWinMainCRTStartup
+
+--- !COFF
+header:
+ Machine: IMAGE_FILE_MACHINE_AMD64
+ Characteristics: []
+sections:
+ - Name: .text
+ Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+ Alignment: 4
+ SectionData: B82A000000C3
+symbols:
+ - Name: .text
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_STATIC
+ SectionDefinition:
+ Length: 6
+ NumberOfRelocations: 0
+ NumberOfLinenumbers: 0
+ CheckSum: 0
+ Number: 0
+ - Name: ENTRY1
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+ - Name: ENTRY2
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+...
deps/lld/test/COFF/guardcf-align.s
@@ -1,3 +1,4 @@
+# REQUIRES: x86
# RUN: llvm-mc -triple x86_64-windows-msvc -filetype=obj -o %t.obj %s
# RUN: yaml2obj < %p/Inputs/guardcf-align-foobar.yaml \
# RUN: > %T/guardcf-align-foobar.obj
deps/lld/test/COFF/subsystem-inference32.test
@@ -0,0 +1,74 @@
+# RUN: sed -e s/ENTRYNAME/_main/ %s | yaml2obj > %t.obj
+# RUN: lld-link /out:%t.exe %t.obj
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck -check-prefix=MAIN %s
+
+# RUN: sed s/ENTRYNAME/_wmain/ %s | yaml2obj > %t.obj
+# RUN: lld-link /out:%t.exe %t.obj
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck -check-prefix=WMAIN %s
+
+# RUN: sed s/ENTRYNAME/_WinMain@16/ %s | yaml2obj > %t.obj
+# RUN: lld-link /out:%t.exe %t.obj
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck -check-prefix=WINMAIN %s
+
+# RUN: sed s/ENTRYNAME/_wWinMain@16/ %s | yaml2obj > %t.obj
+# RUN: lld-link /out:%t.exe %t.obj
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck -check-prefix=WWINMAIN %s
+
+# MAIN: Subsystem: IMAGE_SUBSYSTEM_WINDOWS_CUI
+# WMAIN: Subsystem: IMAGE_SUBSYSTEM_WINDOWS_CUI
+# WINMAIN: Subsystem: IMAGE_SUBSYSTEM_WINDOWS_GUI
+# WWINMAIN: Subsystem: IMAGE_SUBSYSTEM_WINDOWS_GUI
+
+--- !COFF
+header:
+ Machine: IMAGE_FILE_MACHINE_I386
+ Characteristics: []
+sections:
+ - Name: .text
+ Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+ Alignment: 4
+ SectionData: B82A000000C3
+symbols:
+ - Name: .text
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_STATIC
+ SectionDefinition:
+ Length: 6
+ NumberOfRelocations: 0
+ NumberOfLinenumbers: 0
+ CheckSum: 0
+ Number: 0
+ - Name: ENTRYNAME
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+ - Name: _mainCRTStartup
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+ - Name: _wmainCRTStartup
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+ - Name: _WinMainCRTStartup
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+ - Name: _wWinMainCRTStartup
+ Value: 0
+ SectionNumber: 1
+ SimpleType: IMAGE_SYM_TYPE_NULL
+ ComplexType: IMAGE_SYM_DTYPE_NULL
+ StorageClass: IMAGE_SYM_CLASS_EXTERNAL
+...
deps/lld/test/ELF/lto/libcall-archive.ll
@@ -1,3 +1,4 @@
+; REQUIRES: x86
; RUN: rm -f %t.a
; RUN: llvm-as -o %t.o %s
; RUN: llvm-as -o %t2.o %S/Inputs/libcall-archive.ll
deps/lld/test/ELF/icf13.s
@@ -1,3 +1,4 @@
+# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1
# RUN: ld.lld -shared -z notext %t1 -o /dev/null --icf=all --print-icf-sections 2>&1 | FileCheck -allow-empty %s
deps/lld/test/ELF/icf15.s
@@ -1,3 +1,4 @@
+# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1
# RUN: ld.lld %t1 -o /dev/null --icf=all --print-icf-sections 2>&1 | FileCheck -allow-empty %s
deps/lld/test/ELF/icf16.s
@@ -1,3 +1,4 @@
+# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1
# RUN: ld.lld -shared -z notext %t1 -o /dev/null --icf=all --print-icf-sections 2>&1 | FileCheck -allow-empty %s
deps/lld/test/ELF/icf17.s
@@ -1,3 +1,4 @@
+# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1
# RUN: ld.lld %t1 -o /dev/null --icf=all --print-icf-sections 2>&1 | FileCheck -allow-empty %s