1 //===- PowerPCSubtarget.cpp - PPC Subtarget Information -------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the PPC specific subclass of TargetSubtargetInfo.
12 //===----------------------------------------------------------------------===//
14 #include "PPCSubtarget.h"
16 #include "llvm/GlobalValue.h"
17 #include "llvm/Target/TargetMachine.h"
18 #include "llvm/Support/TargetRegistry.h"
21 #define GET_SUBTARGETINFO_TARGET_DESC
22 #define GET_SUBTARGETINFO_CTOR
23 #include "PPCGenSubtargetInfo.inc"
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>
33 /// GetCurrentPowerPCFeatures - Returns the current CPUs features.
34 static const char *GetCurrentPowerPCCPU() {
35 host_basic_info_data_t hostInfo;
36 mach_msg_type_number_t infoCount;
38 infoCount = HOST_BASIC_INFO_COUNT;
39 host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo,
42 if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic";
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";
65 PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU,
66 const std::string &FS, bool is64Bit)
67 : PPCGenSubtargetInfo(TT, CPU, FS)
69 , DarwinDirective(PPC::DIR_NONE)
70 , IsGigaProcessor(false)
71 , Has64BitSupport(false)
78 , HasLazyResolverStubs(false)
79 , IsJITCodeModel(false)
82 // Determine default and user specified characteristics
83 std::string CPUName = CPU;
86 #if defined(__APPLE__)
87 if (CPUName == "generic")
88 CPUName = GetCurrentPowerPCCPU();
91 // Parse features string.
92 ParseSubtargetFeatures(CPUName, FS);
94 // Initialize scheduling itinerary for the specified CPU.
95 InstrItins = getInstrItineraryForCPU(CPUName);
97 // If we are generating code for ppc64, verify that options make sense.
99 Has64BitSupport = true;
100 // Silently force 64-bit register use on ppc64.
104 // If the user requested use of 64-bit regs, but the cpu selected doesn't
105 // support it, ignore.
106 if (use64BitRegs() && !has64BitSupport())
107 Use64BitRegs = false;
109 // Set up darwin-specific properties.
111 HasLazyResolverStubs = true;
114 /// SetJITMode - This is called to inform the subtarget info that we are
115 /// producing code for the JIT.
116 void PPCSubtarget::SetJITMode() {
117 // JIT mode doesn't want lazy resolver stubs, it knows exactly where
118 // everything is. This matters for PPC64, which codegens in PIC mode without
120 HasLazyResolverStubs = false;
122 // Calls to external functions need to use indirect calls
123 IsJITCodeModel = true;
127 /// hasLazyResolverStub - Return true if accesses to the specified global have
128 /// to go through a dyld lazy resolution stub. This means that an extra load
129 /// is required to get the address of the global.
130 bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV,
131 const TargetMachine &TM) const {
132 // We never have stubs if HasLazyResolverStubs=false or if in static mode.
133 if (!HasLazyResolverStubs || TM.getRelocationModel() == Reloc::Static)
135 // If symbol visibility is hidden, the extra load is not needed if
136 // the symbol is definitely defined in the current translation unit.
137 bool isDecl = GV->isDeclaration() && !GV->isMaterializable();
138 if (GV->hasHiddenVisibility() && !isDecl && !GV->hasCommonLinkage())
140 return GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
141 GV->hasCommonLinkage() || isDecl;