1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
//===-- ARMSubtarget.cpp - ARM Subtarget Information ------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ARM specific subclass of TargetSubtarget.
//
//===----------------------------------------------------------------------===//
#include "ARMSubtarget.h"
#include "ARMGenSubtarget.inc"
#include "llvm/GlobalValue.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
static cl::opt<bool>
ReserveR9("arm-reserve-r9", cl::Hidden,
cl::desc("Reserve R9, making it unavailable as GPR"));
static cl::opt<bool>
UseNEONFP("arm-use-neon-fp",
cl::desc("Use NEON for single-precision FP"),
cl::init(false), cl::Hidden);
ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &FS,
bool isThumb)
: ARMArchVersion(V4T)
, ARMFPUType(None)
, UseNEONForSinglePrecisionFP(UseNEONFP)
, IsThumb(isThumb)
, ThumbMode(Thumb1)
, PostRAScheduler(false)
, IsR9Reserved(ReserveR9)
, stackAlignment(4)
, CPUString("generic")
, TargetType(isELF) // Default to ELF unless otherwise specified.
, TargetABI(ARM_ABI_APCS) {
// default to soft float ABI
if (FloatABIType == FloatABI::Default)
FloatABIType = FloatABI::Soft;
// Determine default and user specified characteristics
// Parse features string.
CPUString = ParseSubtargetFeatures(FS, CPUString);
// Set the boolean corresponding to the current target triple, or the default
// if one cannot be determined, to true.
unsigned Len = TT.length();
unsigned Idx = 0;
if (Len >= 5 && TT.substr(0, 4) == "armv")
Idx = 4;
else if (Len >= 6 && TT.substr(0, 5) == "thumb") {
IsThumb = true;
if (Len >= 7 && TT[5] == 'v')
Idx = 6;
}
if (Idx) {
unsigned SubVer = TT[Idx];
if (SubVer > '4' && SubVer <= '9') {
if (SubVer >= '7') {
ARMArchVersion = V7A;
} else if (SubVer == '6') {
ARMArchVersion = V6;
if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == '2')
ARMArchVersion = V6T2;
} else if (SubVer == '5') {
ARMArchVersion = V5T;
if (Len >= Idx+3 && TT[Idx+1] == 't' && TT[Idx+2] == 'e')
ARMArchVersion = V5TE;
}
if (ARMArchVersion >= V6T2)
ThumbMode = Thumb2;
}
}
// Thumb2 implies at least V6T2.
if (ARMArchVersion < V6T2 && ThumbMode >= Thumb2)
ARMArchVersion = V6T2;
if (Len >= 10) {
if (TT.find("-darwin") != std::string::npos)
// arm-darwin
TargetType = isDarwin;
}
if (TT.find("eabi") != std::string::npos)
TargetABI = ARM_ABI_AAPCS;
if (isAAPCS_ABI())
stackAlignment = 8;
if (isTargetDarwin())
IsR9Reserved = ReserveR9 | (ARMArchVersion < V6);
// Set CPU specific features.
if (CPUString == "cortex-a8") {
PostRAScheduler = true;
if (UseNEONFP.getPosition() == 0)
UseNEONForSinglePrecisionFP = true;
}
}
/// GVIsIndirectSymbol - true if the GV will be accessed via an indirect symbol.
bool
ARMSubtarget::GVIsIndirectSymbol(GlobalValue *GV, Reloc::Model RelocM) const {
if (RelocM == Reloc::Static)
return false;
// GV with ghost linkage (in JIT lazy compilation mode) do not require an
// extra load from stub.
bool isDecl = GV->isDeclaration() && !GV->hasNotBeenReadFromBitcode();
if (!isTargetDarwin()) {
// Extra load is needed for all externally visible.
if (GV->hasLocalLinkage() || GV->hasHiddenVisibility())
return false;
return true;
} else {
if (RelocM == Reloc::PIC_) {
// If this is a strong reference to a definition, it is definitely not
// through a stub.
if (!isDecl && !GV->isWeakForLinker())
return false;
// Unless we have a symbol with hidden visibility, we have to go through a
// normal $non_lazy_ptr stub because this symbol might be resolved late.
if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.
return true;
// If symbol visibility is hidden, we have a stub for common symbol
// references and external declarations.
if (isDecl || GV->hasCommonLinkage())
// Hidden $non_lazy_ptr reference.
return true;
return false;
} else {
// If this is a strong reference to a definition, it is definitely not
// through a stub.
if (!isDecl && !GV->isWeakForLinker())
return false;
// Unless we have a symbol with hidden visibility, we have to go through a
// normal $non_lazy_ptr stub because this symbol might be resolved late.
if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.
return true;
}
}
return false;
}
|
