From b866602f061a9c991c3686c82623d3f693a744e5 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Wed, 16 Sep 2009 01:46:41 +0000 Subject: Big change #1 for personality function references: Eliminate the PersonalityPrefix/Suffix & NeedsIndirectEncoding fields from MAI: they aren't part of the asm syntax, they are related to the structure of the object file. To replace their functionality, add a new TLOF::getSymbolForDwarfGlobalReference method which asks targets to decide how to reference a global from EH in a pc-relative way. The default implementation just returns the symbol. The default darwin implementation references the symbol through an indirect $non_lazy_ptr stub. The bizarro x86-64 darwin specialization handles the weird "foo@GOTPCREL+4" hack. DwarfException.cpp now uses this to emit the reference to the symbol in the right way, and this also eliminates another horrible hack from DwarfException.cpp: - if (strcmp(MAI->getPersonalitySuffix(), "+4@GOTPCREL")) - O << "-" << MAI->getPCSymbol(); llvm-svn: 81991 --- llvm/lib/Target/TargetLoweringObjectFile.cpp | 39 ++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'llvm/lib/Target/TargetLoweringObjectFile.cpp') diff --git a/llvm/lib/Target/TargetLoweringObjectFile.cpp b/llvm/lib/Target/TargetLoweringObjectFile.cpp index 825a9d3c973..fd8fd9006e3 100644 --- a/llvm/lib/Target/TargetLoweringObjectFile.cpp +++ b/llvm/lib/Target/TargetLoweringObjectFile.cpp @@ -18,6 +18,7 @@ #include "llvm/Function.h" #include "llvm/GlobalVariable.h" #include "llvm/MC/MCContext.h" +#include "llvm/MC/MCExpr.h" #include "llvm/MC/MCSectionMachO.h" #include "llvm/MC/MCSectionELF.h" #include "llvm/Target/TargetData.h" @@ -275,6 +276,30 @@ TargetLoweringObjectFile::getSectionForConstant(SectionKind Kind) const { return DataSection; } +/// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a +/// pc-relative reference to the specified global variable from exception +/// handling information. In addition to the symbol, this returns +/// by-reference: +/// +/// IsIndirect - True if the returned symbol is actually a stub that contains +/// the address of the symbol, false if the symbol is the global itself. +/// +/// IsPCRel - True if the symbol reference is already pc-relative, false if +/// the caller needs to subtract off the address of the reference from the +/// symbol. +/// +const MCExpr *TargetLoweringObjectFile:: +getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang, + bool &IsIndirect, bool &IsPCRel) const { + // The generic implementation of this just returns a direct reference to the + // symbol. + IsIndirect = false; + IsPCRel = false; + + SmallString<128> Name; + Mang->getNameWithPrefix(Name, GV, false); + return MCSymbolRefExpr::Create(Name.str(), getContext()); +} //===----------------------------------------------------------------------===// @@ -929,6 +954,19 @@ shouldEmitUsedDirectiveFor(const GlobalValue *GV, Mangler *Mang) const { return true; } +const MCExpr *TargetLoweringObjectFileMachO:: +getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang, + bool &IsIndirect, bool &IsPCRel) const { + // The mach-o version of this method defaults to returning a stub reference. + IsIndirect = true; + IsPCRel = false; + + SmallString<128> Name; + Mang->getNameWithPrefix(Name, GV, true); + Name += "$non_lazy_ptr"; + return MCSymbolRefExpr::Create(Name.str(), getContext()); +} + //===----------------------------------------------------------------------===// // COFF @@ -1046,3 +1084,4 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind, return getDataSection(); } + -- cgit v1.2.3