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 "llvm/IR/GlobalValue.h"
12#include "llvm/Support/Host.h"
13#include "MCTargetDesc/SystemZMCTargetDesc.h"
14
15#define GET_SUBTARGETINFO_TARGET_DESC
16#define GET_SUBTARGETINFO_CTOR
17#include "SystemZGenSubtargetInfo.inc"
18
19using namespace llvm;
20
21// Pin the vtabel to this file.
22void SystemZSubtarget::anchor() {}
23
24SystemZSubtarget::SystemZSubtarget(const std::string &TT,
25                                   const std::string &CPU,
26                                   const std::string &FS)
27  : SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false),
28    HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false),
29    TargetTriple(TT) {
30  std::string CPUName = CPU;
31  if (CPUName.empty())
32    CPUName = "generic";
33#if defined(__linux__) && defined(__s390x__)
34  if (CPUName == "generic")
35    CPUName = sys::getHostCPUName();
36#endif
37
38  // Parse features string.
39  ParseSubtargetFeatures(CPUName, FS);
40}
41
42// Return true if GV binds locally under reloc model RM.
43static bool bindsLocally(const GlobalValue *GV, Reloc::Model RM) {
44  // For non-PIC, all symbols bind locally.
45  if (RM == Reloc::Static)
46    return true;
47
48  return GV->hasLocalLinkage() || !GV->hasDefaultVisibility();
49}
50
51bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV,
52                                       Reloc::Model RM,
53                                       CodeModel::Model CM) const {
54  // PC32DBL accesses require the low bit to be clear.  Note that a zero
55  // value selects the default alignment and is therefore OK.
56  if (GV->getAlignment() == 1)
57    return false;
58
59  // For the small model, all locally-binding symbols are in range.
60  if (CM == CodeModel::Small)
61    return bindsLocally(GV, RM);
62
63  // For Medium and above, assume that the symbol is not within the 4GB range.
64  // Taking the address of locally-defined text would be OK, but that
65  // case isn't easy to detect.
66  return false;
67}
68