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 
14 using namespace llvm;
15 
16 #define DEBUG_TYPE "systemz-subtarget"
17 
18 #define GET_SUBTARGETINFO_TARGET_DESC
19 #define GET_SUBTARGETINFO_CTOR
20 #include "SystemZGenSubtargetInfo.inc"
21 
22 // Pin the vtable to this file.
23 void SystemZSubtarget::anchor() {}
24 
25 SystemZSubtarget &
26 SystemZSubtarget::initializeSubtargetDependencies(StringRef CPU, StringRef FS) {
27   std::string CPUName = CPU;
28   if (CPUName.empty())
29     CPUName = "generic";
30   // Parse features string.
31   ParseSubtargetFeatures(CPUName, FS);
32   return *this;
33 }
34 
35 SystemZSubtarget::SystemZSubtarget(const std::string &TT,
36                                    const std::string &CPU,
37                                    const std::string &FS,
38                                    const TargetMachine &TM)
39     : SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false),
40       HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false),
41       HasPopulationCount(false), HasFastSerialization(false),
42       HasInterlockedAccess1(false), HasMiscellaneousExtensions(false),
43       HasTransactionalExecution(false), HasProcessorAssist(false),
44       HasVector(false),
45       TargetTriple(TT), InstrInfo(initializeSubtargetDependencies(CPU, FS)),
46       TLInfo(TM, *this), TSInfo(*TM.getDataLayout()), FrameLowering() {}
47 
48 // Return true if GV binds locally under reloc model RM.
49 static bool bindsLocally(const GlobalValue *GV, Reloc::Model RM) {
50   // For non-PIC, all symbols bind locally.
51   if (RM == Reloc::Static)
52     return true;
53 
54   return GV->hasLocalLinkage() || !GV->hasDefaultVisibility();
55 }
56 
57 bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV,
58                                        Reloc::Model RM,
59                                        CodeModel::Model CM) const {
60   // PC32DBL accesses require the low bit to be clear.  Note that a zero
61   // value selects the default alignment and is therefore OK.
62   if (GV->getAlignment() == 1)
63     return false;
64 
65   // For the small model, all locally-binding symbols are in range.
66   if (CM == CodeModel::Small)
67     return bindsLocally(GV, RM);
68 
69   // For Medium and above, assume that the symbol is not within the 4GB range.
70   // Taking the address of locally-defined text would be OK, but that
71   // case isn't easy to detect.
72   return false;
73 }
74