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/Module.h"
17 #include "llvm/Target/TargetMachine.h"
18 #include "PPCGenSubtarget.inc"
21 #if defined(__APPLE__)
22 #include <mach/mach.h>
23 #include <mach/mach_host.h>
24 #include <mach/host_info.h>
25 #include <mach/machine.h>
27 /// GetCurrentPowerPCFeatures - Returns the current CPUs features.
28 static const char *GetCurrentPowerPCCPU() {
29 host_basic_info_data_t hostInfo;
30 mach_msg_type_number_t infoCount;
32 infoCount = HOST_BASIC_INFO_COUNT;
33 host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo,
36 if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic";
38 switch(hostInfo.cpu_subtype) {
39 case CPU_SUBTYPE_POWERPC_601: return "601";
40 case CPU_SUBTYPE_POWERPC_602: return "602";
41 case CPU_SUBTYPE_POWERPC_603: return "603";
42 case CPU_SUBTYPE_POWERPC_603e: return "603e";
43 case CPU_SUBTYPE_POWERPC_603ev: return "603ev";
44 case CPU_SUBTYPE_POWERPC_604: return "604";
45 case CPU_SUBTYPE_POWERPC_604e: return "604e";
46 case CPU_SUBTYPE_POWERPC_620: return "620";
47 case CPU_SUBTYPE_POWERPC_750: return "750";
48 case CPU_SUBTYPE_POWERPC_7400: return "7400";
49 case CPU_SUBTYPE_POWERPC_7450: return "7450";
50 case CPU_SUBTYPE_POWERPC_970: return "970";
59 PPCSubtarget::PPCSubtarget(const TargetMachine &tm, const Module &M,
60 const std::string &FS, bool is64Bit)
63 , DarwinDirective(PPC::DIR_NONE)
64 , IsGigaProcessor(false)
65 , Has64BitSupport(false)
71 , HasLazyResolverStubs(false)
74 // Determine default and user specified characteristics
75 std::string CPU = "generic";
76 #if defined(__APPLE__)
77 CPU = GetCurrentPowerPCCPU();
80 // Parse features string.
81 ParseSubtargetFeatures(FS, CPU);
83 // If we are generating code for ppc64, verify that options make sense.
85 if (!has64BitSupport()) {
86 cerr << "PPC: Generation of 64-bit code for a 32-bit processor "
87 << "requested. Ignoring 32-bit processor feature.\n";
88 Has64BitSupport = true;
90 // Silently force 64-bit register use on ppc64.
94 // If the user requested use of 64-bit regs, but the cpu selected doesn't
95 // support it, warn and ignore.
96 if (use64BitRegs() && !has64BitSupport()) {
97 cerr << "PPC: 64-bit registers requested on CPU without support. "
98 << "Disabling 64-bit register use.\n";
102 // Set the boolean corresponding to the current target triple, or the default
103 // if one cannot be determined, to true.
104 const std::string &TT = M.getTargetTriple();
105 if (TT.length() > 7) {
106 // Determine which version of darwin this is.
107 size_t DarwinPos = TT.find("-darwin");
108 if (DarwinPos != std::string::npos) {
109 if (isdigit(TT[DarwinPos+7]))
110 DarwinVers = atoi(&TT[DarwinPos+7]);
112 DarwinVers = 8; // Minimum supported darwin is Tiger.
114 } else if (TT.empty()) {
115 // Try to autosense the subtarget from the host compiler.
116 #if defined(__APPLE__)
117 #if __APPLE_CC__ > 5400
118 DarwinVers = 9; // GCC 5400+ is Leopard.
120 DarwinVers = 8; // Minimum supported darwin is Tiger.
125 // Set up darwin-specific properties.
127 HasLazyResolverStubs = true;
128 AsmFlavor = NewMnemonic;
130 AsmFlavor = OldMnemonic;
134 /// SetJITMode - This is called to inform the subtarget info that we are
135 /// producing code for the JIT.
136 void PPCSubtarget::SetJITMode() {
137 // JIT mode doesn't want lazy resolver stubs, it knows exactly where
138 // everything is. This matters for PPC64, which codegens in PIC mode without
140 HasLazyResolverStubs = false;
144 /// hasLazyResolverStub - Return true if accesses to the specified global have
145 /// to go through a dyld lazy resolution stub. This means that an extra load
146 /// is required to get the address of the global.
147 bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV) const {
148 // We never hae stubs if HasLazyResolverStubs=false or if in static mode.
149 if (!HasLazyResolverStubs || TM.getRelocationModel() == Reloc::Static)
152 return GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
153 (GV->isDeclaration() && !GV->hasNotBeenReadFromBitcode());