From b2dfb89e0e7f1ee3e4fe4a3a1b3af148f0aec34f Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Tue, 9 Sep 2008 01:21:22 +0000 Subject: [PATCH] Fix logic for not emitting no-dead-strip for some objects in llvm.used (thanks Anton). Makes visible the magic 'l' prefix for symbols on Darwin which are to be passed through the assembler, then removed at linktime (previously all references to this had been hidden in the ObjC FE code, oh well). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55973 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Target/TargetAsmInfo.h | 10 +++++++++- lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 16 ++++++++++++++-- lib/Target/ARM/ARMTargetAsmInfo.cpp | 1 + lib/Target/PowerPC/PPCTargetAsmInfo.cpp | 1 + lib/Target/TargetAsmInfo.cpp | 1 + lib/Target/X86/X86TargetAsmInfo.cpp | 1 + 6 files changed, 27 insertions(+), 3 deletions(-) diff --git a/include/llvm/Target/TargetAsmInfo.h b/include/llvm/Target/TargetAsmInfo.h index ff2491e7ab3..bbb58527eb6 100644 --- a/include/llvm/Target/TargetAsmInfo.h +++ b/include/llvm/Target/TargetAsmInfo.h @@ -216,10 +216,15 @@ namespace llvm { const char *GlobalPrefix; // Defaults to "" /// PrivateGlobalPrefix - This prefix is used for globals like constant - /// pool entries that are completely private to the .o file and should not + /// pool entries that are completely private to the .s file and should not /// have names in the .o file. This is often "." or "L". const char *PrivateGlobalPrefix; // Defaults to "." + /// LessPrivateGlobalPrefix - This prefix is used for some Objective C + /// metadata symbols that should be passed through the assembler but be + /// removed by the linker. This is "l" on Darwin. + const char *LessPrivateGlobalPrefix; // Defaults to "" + /// JumpTableSpecialLabelPrefix - If not null, a extra (dead) label is /// emitted before jump tables with the specified prefix. const char *JumpTableSpecialLabelPrefix; // Default to null. @@ -653,6 +658,9 @@ namespace llvm { const char *getPrivateGlobalPrefix() const { return PrivateGlobalPrefix; } + const char *getLessPrivateGlobalPrefix() const { + return LessPrivateGlobalPrefix; + } const char *getJumpTableSpecialLabelPrefix() const { return JumpTableSpecialLabelPrefix; } diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp index 273253ae23c..f041f3be56f 100644 --- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp +++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp @@ -452,7 +452,9 @@ const GlobalValue * AsmPrinter::findGlobalValue(const Constant *CV) { /// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each /// global in the specified llvm.used list as being used with this directive. -/// Non-globals (i.e. internal linkage) should not be emitted. +/// Internally linked data beginning with the PrivateGlobalPrefix or the +/// LessPrivateGlobalPrefix does not have the directive emitted (this +/// occurs in ObjC metadata). void AsmPrinter::EmitLLVMUsedList(Constant *List) { const char *Directive = TAI->getUsedDirective(); @@ -462,7 +464,17 @@ void AsmPrinter::EmitLLVMUsedList(Constant *List) { for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { const GlobalValue *GV = findGlobalValue(InitList->getOperand(i)); - if (GV && (!GV->hasInternalLinkage() || isa(GV))) { + if (GV) { + if (GV->hasInternalLinkage() && !isa(GV) && + ((strlen(TAI->getPrivateGlobalPrefix()) != 0 && + Mang->getValueName(GV) + .substr(0,strlen(TAI->getPrivateGlobalPrefix())) == + TAI->getPrivateGlobalPrefix()) || + (strlen(TAI->getLessPrivateGlobalPrefix()) != 0 && + Mang->getValueName(GV) + .substr(0,strlen(TAI->getLessPrivateGlobalPrefix())) == + TAI->getLessPrivateGlobalPrefix()))) + continue; O << Directive; EmitConstantValueOnly(InitList->getOperand(i)); O << '\n'; diff --git a/lib/Target/ARM/ARMTargetAsmInfo.cpp b/lib/Target/ARM/ARMTargetAsmInfo.cpp index 3e057359582..a1a00a2cdae 100644 --- a/lib/Target/ARM/ARMTargetAsmInfo.cpp +++ b/lib/Target/ARM/ARMTargetAsmInfo.cpp @@ -62,6 +62,7 @@ ARMDarwinTargetAsmInfo::ARMDarwinTargetAsmInfo(const ARMTargetMachine &TM): GlobalPrefix = "_"; PrivateGlobalPrefix = "L"; + LessPrivateGlobalPrefix = "l"; StringConstantPrefix = "\1LC"; BSSSection = 0; // no BSS section ZeroDirective = "\t.space\t"; diff --git a/lib/Target/PowerPC/PPCTargetAsmInfo.cpp b/lib/Target/PowerPC/PPCTargetAsmInfo.cpp index 1b8c1a5fb3c..fc98e57c82a 100644 --- a/lib/Target/PowerPC/PPCTargetAsmInfo.cpp +++ b/lib/Target/PowerPC/PPCTargetAsmInfo.cpp @@ -38,6 +38,7 @@ PPCDarwinTargetAsmInfo::PPCDarwinTargetAsmInfo(const PPCTargetMachine &TM): CommentString = ";"; GlobalPrefix = "_"; PrivateGlobalPrefix = "L"; + LessPrivateGlobalPrefix = "l"; StringConstantPrefix = "\1LC"; ConstantPoolSection = "\t.const\t"; JumpTableDataSection = ".const"; diff --git a/lib/Target/TargetAsmInfo.cpp b/lib/Target/TargetAsmInfo.cpp index 6baebd0ffe7..06b77dd26aa 100644 --- a/lib/Target/TargetAsmInfo.cpp +++ b/lib/Target/TargetAsmInfo.cpp @@ -50,6 +50,7 @@ TargetAsmInfo::TargetAsmInfo() : CommentString("#"), GlobalPrefix(""), PrivateGlobalPrefix("."), + LessPrivateGlobalPrefix(""), JumpTableSpecialLabelPrefix(0), GlobalVarAddrPrefix(""), GlobalVarAddrSuffix(""), diff --git a/lib/Target/X86/X86TargetAsmInfo.cpp b/lib/Target/X86/X86TargetAsmInfo.cpp index be390c23963..64858f89bd5 100644 --- a/lib/Target/X86/X86TargetAsmInfo.cpp +++ b/lib/Target/X86/X86TargetAsmInfo.cpp @@ -136,6 +136,7 @@ X86DarwinTargetAsmInfo::X86DarwinTargetAsmInfo(const X86TargetMachine &TM): Data64bitsDirective = 0; // we can't emit a 64-bit unit ZeroDirective = "\t.space\t"; // ".space N" emits N zeros. PrivateGlobalPrefix = "L"; // Marker for constant pool idxs + LessPrivateGlobalPrefix = "l"; // Marker for some ObjC metadata BSSSection = 0; // no BSS section. ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill if (DTM->getRelocationModel() != Reloc::Static)