1 //===-- ARMSubtarget.cpp - ARM Subtarget Information ------------*- C++ -*-===//
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 ARM specific subclass of TargetSubtarget.
12 //===----------------------------------------------------------------------===//
14 #include "ARMSubtarget.h"
15 #include "ARMGenSubtarget.inc"
16 #include "llvm/GlobalValue.h"
17 #include "llvm/Target/TargetOptions.h"
18 #include "llvm/Support/CommandLine.h"
22 ReserveR9("arm-reserve-r9", cl::Hidden,
23 cl::desc("Reserve R9, making it unavailable as GPR"));
25 ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &FS,
29 , UseNEONForSinglePrecisionFP(false)
32 , PostRAScheduler(false)
33 , IsR9Reserved(ReserveR9)
35 , CPUString("generic")
36 , TargetType(isELF) // Default to ELF unless otherwise specified.
37 , TargetABI(ARM_ABI_APCS) {
38 // default to soft float ABI
39 if (FloatABIType == FloatABI::Default)
40 FloatABIType = FloatABI::Soft;
42 // Determine default and user specified characteristics
44 // Parse features string.
45 CPUString = ParseSubtargetFeatures(FS, CPUString);
47 // Set the boolean corresponding to the current target triple, or the default
48 // if one cannot be determined, to true.
49 unsigned Len = TT.length();
52 if (Len >= 5 && TT.substr(0, 4) == "armv")
54 else if (Len >= 6 && TT.substr(0, 5) == "thumb") {
56 if (Len >= 7 && TT[5] == 'v')
60 unsigned SubVer = TT[Idx];
61 if (SubVer > '4' && SubVer <= '9') {
64 } else if (SubVer == '6') {
66 if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == '2')
67 ARMArchVersion = V6T2;
68 } else if (SubVer == '5') {
70 if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == 'e')
71 ARMArchVersion = V5TE;
73 if (ARMArchVersion >= V6T2)
78 // Thumb2 implies at least V6T2.
79 if (ARMArchVersion < V6T2 && ThumbMode >= Thumb2)
80 ARMArchVersion = V6T2;
83 if (TT.find("-darwin") != std::string::npos)
85 TargetType = isDarwin;
88 if (TT.find("eabi") != std::string::npos)
89 TargetABI = ARM_ABI_AAPCS;
95 IsR9Reserved = ReserveR9 | (ARMArchVersion < V6);
98 /// GVIsIndirectSymbol - true if the GV will be accessed via an indirect symbol.
100 ARMSubtarget::GVIsIndirectSymbol(GlobalValue *GV, Reloc::Model RelocM) const {
101 if (RelocM == Reloc::Static)
104 // GV with ghost linkage (in JIT lazy compilation mode) do not require an
105 // extra load from stub.
106 bool isDecl = GV->isDeclaration() && !GV->hasNotBeenReadFromBitcode();
108 if (!isTargetDarwin()) {
109 // Extra load is needed for all externally visible.
110 if (GV->hasLocalLinkage() || GV->hasHiddenVisibility())
114 if (RelocM == Reloc::PIC_) {
115 // If this is a strong reference to a definition, it is definitely not
117 if (!isDecl && !GV->isWeakForLinker())
120 // Unless we have a symbol with hidden visibility, we have to go through a
121 // normal $non_lazy_ptr stub because this symbol might be resolved late.
122 if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.
125 // If symbol visibility is hidden, we have a stub for common symbol
126 // references and external declarations.
127 if (isDecl || GV->hasCommonLinkage())
128 // Hidden $non_lazy_ptr reference.
133 // If this is a strong reference to a definition, it is definitely not
135 if (!isDecl && !GV->isWeakForLinker())
138 // Unless we have a symbol with hidden visibility, we have to go through a
139 // normal $non_lazy_ptr stub because this symbol might be resolved late.
140 if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.