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 static cl::opt<bool> UseSubRegLiveness(
23     "systemz-subreg-liveness",
24     cl::desc("Enable subregister liveness tracking for SystemZ (experimental)"),
25     cl::Hidden);
26 
27 // Pin the vtable to this file.
28 void SystemZSubtarget::anchor() {}
29 
30 SystemZSubtarget &
31 SystemZSubtarget::initializeSubtargetDependencies(StringRef CPU, StringRef FS) {
32   std::string CPUName = CPU;
33   if (CPUName.empty())
34     CPUName = "generic";
35   // Parse features string.
36   ParseSubtargetFeatures(CPUName, FS);
37   return *this;
38 }
39 
40 SystemZSubtarget::SystemZSubtarget(const Triple &TT, const std::string &CPU,
41                                    const std::string &FS,
42                                    const TargetMachine &TM)
43     : SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false),
44       HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false),
45       HasPopulationCount(false), HasMessageSecurityAssist3(false),
46       HasMessageSecurityAssist4(false), HasResetReferenceBitsMultiple(false),
47       HasFastSerialization(false), HasInterlockedAccess1(false),
48       HasMiscellaneousExtensions(false),
49       HasExecutionHint(false), HasLoadAndTrap(false),
50       HasTransactionalExecution(false), HasProcessorAssist(false),
51       HasDFPZonedConversion(false), HasEnhancedDAT2(false),
52       HasVector(false), HasLoadStoreOnCond2(false),
53       HasLoadAndZeroRightmostByte(false), HasMessageSecurityAssist5(false),
54       HasDFPPackedConversion(false),
55       HasMiscellaneousExtensions2(false), HasGuardedStorage(false),
56       HasMessageSecurityAssist7(false), HasMessageSecurityAssist8(false),
57       HasVectorEnhancements1(false), HasVectorPackedDecimal(false),
58       HasInsertReferenceBitsMultiple(false),
59       TargetTriple(TT), InstrInfo(initializeSubtargetDependencies(CPU, FS)),
60       TLInfo(TM, *this), TSInfo(), FrameLowering() {}
61 
62 
63 bool SystemZSubtarget::enableSubRegLiveness() const {
64   return UseSubRegLiveness;
65 }
66 
67 bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV,
68                                        CodeModel::Model CM) const {
69   // PC32DBL accesses require the low bit to be clear.  Note that a zero
70   // value selects the default alignment and is therefore OK.
71   if (GV->getAlignment() == 1)
72     return false;
73 
74   // For the small model, all locally-binding symbols are in range.
75   if (CM == CodeModel::Small)
76     return TLInfo.getTargetMachine().shouldAssumeDSOLocal(*GV->getParent(), GV);
77 
78   // For Medium and above, assume that the symbol is not within the 4GB range.
79   // Taking the address of locally-defined text would be OK, but that
80   // case isn't easy to detect.
81   return false;
82 }
83