1 //===-- SystemZSubtarget.cpp - SystemZ subtarget information --------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "SystemZSubtarget.h" 11 #include "llvm/IR/GlobalValue.h" 12 #include "llvm/Support/Host.h" 13 #include "MCTargetDesc/SystemZMCTargetDesc.h" 14 15 #define GET_SUBTARGETINFO_TARGET_DESC 16 #define GET_SUBTARGETINFO_CTOR 17 #include "SystemZGenSubtargetInfo.inc" 18 19 using namespace llvm; 20 21 SystemZSubtarget::SystemZSubtarget(const std::string &TT, 22 const std::string &CPU, 23 const std::string &FS) 24 : SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false), 25 HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false), 26 TargetTriple(TT) { 27 std::string CPUName = CPU; 28 if (CPUName.empty()) 29 CPUName = "generic"; 30 #if defined(__linux__) && defined(__s390x__) 31 if (CPUName == "generic") 32 CPUName = sys::getHostCPUName(); 33 #endif 34 35 // Parse features string. 36 ParseSubtargetFeatures(CPUName, FS); 37 } 38 39 // Return true if GV binds locally under reloc model RM. 40 static bool bindsLocally(const GlobalValue *GV, Reloc::Model RM) { 41 // For non-PIC, all symbols bind locally. 42 if (RM == Reloc::Static) 43 return true; 44 45 return GV->hasLocalLinkage() || !GV->hasDefaultVisibility(); 46 } 47 48 bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV, 49 Reloc::Model RM, 50 CodeModel::Model CM) const { 51 // PC32DBL accesses require the low bit to be clear. Note that a zero 52 // value selects the default alignment and is therefore OK. 53 if (GV->getAlignment() == 1) 54 return false; 55 56 // For the small model, all locally-binding symbols are in range. 57 if (CM == CodeModel::Small) 58 return bindsLocally(GV, RM); 59 60 // For Medium and above, assume that the symbol is not within the 4GB range. 61 // Taking the address of locally-defined text would be OK, but that 62 // case isn't easy to detect. 63 return false; 64 } 65