1 //===-- MCAsmInfoDarwin.cpp - Darwin asm properties -------------*- 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 defines target asm properties related what form asm statements
11 // should take in general on Darwin-based targets
13 //===----------------------------------------------------------------------===//
15 #include "llvm/MC/MCAsmInfoDarwin.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCExpr.h"
18 #include "llvm/MC/MCSectionMachO.h"
21 bool MCAsmInfoDarwin::isSectionAtomizableBySymbols(
22 const MCSection &Section) const {
23 const MCSectionMachO &SMO = static_cast<const MCSectionMachO &>(Section);
25 // Sections holding 1 byte strings are atomized based on the data they
27 // Sections holding 2 byte strings require symbols in order to be atomized.
28 // There is no dedicated section for 4 byte strings.
29 if (SMO.getType() == MachO::S_CSTRING_LITERALS)
32 if (SMO.getSegmentName() == "__DATA" && SMO.getSectionName() == "__cfstring")
35 if (SMO.getSegmentName() == "__DATA" &&
36 SMO.getSectionName() == "__objc_classrefs")
39 switch (SMO.getType()) {
43 // These sections are atomized at the element boundaries without using
45 case MachO::S_4BYTE_LITERALS:
46 case MachO::S_8BYTE_LITERALS:
47 case MachO::S_16BYTE_LITERALS:
48 case MachO::S_LITERAL_POINTERS:
49 case MachO::S_NON_LAZY_SYMBOL_POINTERS:
50 case MachO::S_LAZY_SYMBOL_POINTERS:
51 case MachO::S_MOD_INIT_FUNC_POINTERS:
52 case MachO::S_MOD_TERM_FUNC_POINTERS:
53 case MachO::S_INTERPOSING:
58 MCAsmInfoDarwin::MCAsmInfoDarwin() {
59 // Common settings for all Darwin targets.
61 LinkerPrivateGlobalPrefix = "l";
62 HasSingleParameterDotFile = false;
63 HasSubsectionsViaSymbols = true;
65 AlignmentIsInBytes = false;
66 COMMDirectiveAlignmentIsInBytes = false;
67 LCOMMDirectiveAlignmentType = LCOMM::Log2Alignment;
68 InlineAsmStart = " InlineAsm Start";
69 InlineAsmEnd = " InlineAsm End";
72 HasWeakDefDirective = true;
73 HasWeakDefCanBeHiddenDirective = true;
74 WeakRefDirective = "\t.weak_reference ";
75 ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
76 HasMachoZeroFillDirective = true; // Uses .zerofill
77 HasMachoTBSSDirective = true; // Uses .tbss
78 HasStaticCtorDtorReferenceInStaticMode = true;
80 // FIXME: Change this once MC is the system assembler.
81 HasAggressiveSymbolFolding = false;
83 HiddenVisibilityAttr = MCSA_PrivateExtern;
84 HiddenDeclarationVisibilityAttr = MCSA_Invalid;
86 // Doesn't support protected visibility.
87 ProtectedVisibilityAttr = MCSA_Invalid;
89 HasDotTypeDotSizeDirective = false;
90 HasNoDeadStrip = true;
92 DwarfUsesRelocationsAcrossSections = false;
94 UseIntegratedAssembler = true;
95 SetDirectiveSuppressesReloc = true;
97 // FIXME: For now keep the previous behavior, AShr, matching the previous
98 // behavior of as(1) (both -q and -Q: resp. LLVM and gas v1.38).
99 // If/when this changes, the AArch64 Darwin special case can go away.
100 UseLogicalShr = false;