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 "MCTargetDesc/SystemZMCTargetDesc.h" 12 #include "llvm/IR/GlobalValue.h" 13 #include "llvm/Support/Host.h" 14 15 using namespace llvm; 16 17 #define DEBUG_TYPE "systemz-subtarget" 18 19 #define GET_SUBTARGETINFO_TARGET_DESC 20 #define GET_SUBTARGETINFO_CTOR 21 #include "SystemZGenSubtargetInfo.inc" 22 23 // Pin the vtable to this file. 24 void SystemZSubtarget::anchor() {} 25 26 SystemZSubtarget & 27 SystemZSubtarget::initializeSubtargetDependencies(StringRef CPU, StringRef FS) { 28 std::string CPUName = CPU; 29 if (CPUName.empty()) 30 CPUName = "generic"; 31 #if defined(__linux__) && defined(__s390x__) 32 if (CPUName == "generic") 33 CPUName = sys::getHostCPUName(); 34 #endif 35 // Parse features string. 36 ParseSubtargetFeatures(CPUName, FS); 37 return *this; 38 } 39 40 SystemZSubtarget::SystemZSubtarget(const std::string &TT, 41 const std::string &CPU, 42 const std::string &FS, 43 const TargetMachine &TM) 44 : SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false), 45 HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false), 46 HasFastSerialization(false), HasInterlockedAccess1(false), 47 TargetTriple(TT), 48 // Make sure that global data has at least 16 bits of alignment by 49 // default, so that we can refer to it using LARL. We don't have any 50 // special requirements for stack variables though. 51 DL("E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-a:8:16-n32:64"), 52 InstrInfo(initializeSubtargetDependencies(CPU, FS)), TLInfo(TM), 53 TSInfo(DL), FrameLowering() {} 54 55 // Return true if GV binds locally under reloc model RM. 56 static bool bindsLocally(const GlobalValue *GV, Reloc::Model RM) { 57 // For non-PIC, all symbols bind locally. 58 if (RM == Reloc::Static) 59 return true; 60 61 return GV->hasLocalLinkage() || !GV->hasDefaultVisibility(); 62 } 63 64 bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV, 65 Reloc::Model RM, 66 CodeModel::Model CM) const { 67 // PC32DBL accesses require the low bit to be clear. Note that a zero 68 // value selects the default alignment and is therefore OK. 69 if (GV->getAlignment() == 1) 70 return false; 71 72 // For the small model, all locally-binding symbols are in range. 73 if (CM == CodeModel::Small) 74 return bindsLocally(GV, RM); 75 76 // For Medium and above, assume that the symbol is not within the 4GB range. 77 // Taking the address of locally-defined text would be OK, but that 78 // case isn't easy to detect. 79 return false; 80 } 81