1//===- PowerPCSubtarget.cpp - PPC 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// This file implements the PPC specific subclass of TargetSubtargetInfo. 11// 12//===----------------------------------------------------------------------===// 13 14#include "PPCSubtarget.h" 15#include "PPC.h" 16#include "llvm/GlobalValue.h" 17#include "llvm/Target/TargetMachine.h" 18#include "llvm/Support/TargetRegistry.h" 19#include <cstdlib> 20 21#define GET_SUBTARGETINFO_TARGET_DESC 22#define GET_SUBTARGETINFO_CTOR 23#include "PPCGenSubtargetInfo.inc" 24 25using namespace llvm; 26 27#if defined(__APPLE__) 28#include <mach/mach.h> 29#include <mach/mach_host.h> 30#include <mach/host_info.h> 31#include <mach/machine.h> 32 33/// GetCurrentPowerPCFeatures - Returns the current CPUs features. 34static const char *GetCurrentPowerPCCPU() { 35 host_basic_info_data_t hostInfo; 36 mach_msg_type_number_t infoCount; 37 38 infoCount = HOST_BASIC_INFO_COUNT; 39 host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo, 40 &infoCount); 41 42 if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic"; 43 44 switch(hostInfo.cpu_subtype) { 45 case CPU_SUBTYPE_POWERPC_601: return "601"; 46 case CPU_SUBTYPE_POWERPC_602: return "602"; 47 case CPU_SUBTYPE_POWERPC_603: return "603"; 48 case CPU_SUBTYPE_POWERPC_603e: return "603e"; 49 case CPU_SUBTYPE_POWERPC_603ev: return "603ev"; 50 case CPU_SUBTYPE_POWERPC_604: return "604"; 51 case CPU_SUBTYPE_POWERPC_604e: return "604e"; 52 case CPU_SUBTYPE_POWERPC_620: return "620"; 53 case CPU_SUBTYPE_POWERPC_750: return "750"; 54 case CPU_SUBTYPE_POWERPC_7400: return "7400"; 55 case CPU_SUBTYPE_POWERPC_7450: return "7450"; 56 case CPU_SUBTYPE_POWERPC_970: return "970"; 57 default: ; 58 } 59 60 return "generic"; 61} 62#endif 63 64 65PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU, 66 const std::string &FS, bool is64Bit) 67 : PPCGenSubtargetInfo(TT, CPU, FS) 68 , StackAlignment(16) 69 , DarwinDirective(PPC::DIR_NONE) 70 , IsGigaProcessor(false) 71 , Has64BitSupport(false) 72 , Use64BitRegs(false) 73 , IsPPC64(is64Bit) 74 , HasAltivec(false) 75 , HasFSQRT(false) 76 , HasSTFIWX(false) 77 , HasLazyResolverStubs(false) 78 , IsJITCodeModel(false) 79 , TargetTriple(TT) { 80 81 // Determine default and user specified characteristics 82 std::string CPUName = CPU; 83 if (CPUName.empty()) 84 CPUName = "generic"; 85#if defined(__APPLE__) 86 if (CPUName == "generic") 87 CPUName = GetCurrentPowerPCCPU(); 88#endif 89 90 // Parse features string. 91 ParseSubtargetFeatures(CPUName, FS); 92 93 // Initialize scheduling itinerary for the specified CPU. 94 InstrItins = getInstrItineraryForCPU(CPUName); 95 96 // If we are generating code for ppc64, verify that options make sense. 97 if (is64Bit) { 98 Has64BitSupport = true; 99 // Silently force 64-bit register use on ppc64. 100 Use64BitRegs = true; 101 } 102 103 // If the user requested use of 64-bit regs, but the cpu selected doesn't 104 // support it, ignore. 105 if (use64BitRegs() && !has64BitSupport()) 106 Use64BitRegs = false; 107 108 // Set up darwin-specific properties. 109 if (isDarwin()) 110 HasLazyResolverStubs = true; 111} 112 113/// SetJITMode - This is called to inform the subtarget info that we are 114/// producing code for the JIT. 115void PPCSubtarget::SetJITMode() { 116 // JIT mode doesn't want lazy resolver stubs, it knows exactly where 117 // everything is. This matters for PPC64, which codegens in PIC mode without 118 // stubs. 119 HasLazyResolverStubs = false; 120 121 // Calls to external functions need to use indirect calls 122 IsJITCodeModel = true; 123} 124 125 126/// hasLazyResolverStub - Return true if accesses to the specified global have 127/// to go through a dyld lazy resolution stub. This means that an extra load 128/// is required to get the address of the global. 129bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV, 130 const TargetMachine &TM) const { 131 // We never have stubs if HasLazyResolverStubs=false or if in static mode. 132 if (!HasLazyResolverStubs || TM.getRelocationModel() == Reloc::Static) 133 return false; 134 // If symbol visibility is hidden, the extra load is not needed if 135 // the symbol is definitely defined in the current translation unit. 136 bool isDecl = GV->isDeclaration() && !GV->isMaterializable(); 137 if (GV->hasHiddenVisibility() && !isDecl && !GV->hasCommonLinkage()) 138 return false; 139 return GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() || 140 GV->hasCommonLinkage() || isDecl; 141} 142