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 TargetSubtarget.
12 //===----------------------------------------------------------------------===//
14 #include "PPCSubtarget.h"
16 #include "llvm/GlobalValue.h"
17 #include "llvm/Target/TargetMachine.h"
18 #include "PPCGenSubtarget.inc"
22 #if defined(__APPLE__)
23 #include <mach/mach.h>
24 #include <mach/mach_host.h>
25 #include <mach/host_info.h>
26 #include <mach/machine.h>
28 /// GetCurrentPowerPCFeatures - Returns the current CPUs features.
29 static const char *GetCurrentPowerPCCPU() {
30 host_basic_info_data_t hostInfo;
31 mach_msg_type_number_t infoCount;
33 infoCount = HOST_BASIC_INFO_COUNT;
34 host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo,
37 if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic";
39 switch(hostInfo.cpu_subtype) {
40 case CPU_SUBTYPE_POWERPC_601: return "601";
41 case CPU_SUBTYPE_POWERPC_602: return "602";
42 case CPU_SUBTYPE_POWERPC_603: return "603";
43 case CPU_SUBTYPE_POWERPC_603e: return "603e";
44 case CPU_SUBTYPE_POWERPC_603ev: return "603ev";
45 case CPU_SUBTYPE_POWERPC_604: return "604";
46 case CPU_SUBTYPE_POWERPC_604e: return "604e";
47 case CPU_SUBTYPE_POWERPC_620: return "620";
48 case CPU_SUBTYPE_POWERPC_750: return "750";
49 case CPU_SUBTYPE_POWERPC_7400: return "7400";
50 case CPU_SUBTYPE_POWERPC_7450: return "7450";
51 case CPU_SUBTYPE_POWERPC_970: return "970";
60 PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &FS,
63 , DarwinDirective(PPC::DIR_NONE)
64 , IsGigaProcessor(false)
65 , Has64BitSupport(false)
71 , HasLazyResolverStubs(false)
72 , IsJITCodeModel(false)
75 // Determine default and user specified characteristics
76 std::string CPU = "generic";
77 #if defined(__APPLE__)
78 CPU = GetCurrentPowerPCCPU();
81 // Parse features string.
82 ParseSubtargetFeatures(FS, CPU);
84 // If we are generating code for ppc64, verify that options make sense.
86 Has64BitSupport = true;
87 // Silently force 64-bit register use on ppc64.
91 // If the user requested use of 64-bit regs, but the cpu selected doesn't
92 // support it, ignore.
93 if (use64BitRegs() && !has64BitSupport())
96 // Set the boolean corresponding to the current target triple, or the default
97 // if one cannot be determined, to true.
98 if (TT.length() > 7) {
99 // Determine which version of darwin this is.
100 size_t DarwinPos = TT.find("-darwin");
101 if (DarwinPos != std::string::npos) {
102 if (isdigit(TT[DarwinPos+7]))
103 DarwinVers = atoi(&TT[DarwinPos+7]);
105 DarwinVers = 8; // Minimum supported darwin is Tiger.
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;