//===- MCSectionMachO.h - MachO Machine Code Sections -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the MCSectionMachO class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCSECTIONMACHO_H
#define LLVM_MC_MCSECTIONMACHO_H
#include "llvm/MC/MCSection.h"
namespace llvm {
/// MCSectionMachO - This represents a section on a Mach-O system (used by
/// Mac OS X). On a Mac system, these are also described in
/// /usr/include/mach-o/loader.h.
class MCSectionMachO : public MCSection {
char SegmentName[16]; // Not necessarily null terminated!
char SectionName[16]; // Not necessarily null terminated!
/// TypeAndAttributes - This is the SECTION_TYPE and SECTION_ATTRIBUTES
/// field of a section, drawn from the enums below.
unsigned TypeAndAttributes;
/// Reserved2 - The 'reserved2' field of a section, used to represent the
/// size of stubs, for example.
unsigned Reserved2;
MCSectionMachO(StringRef Segment, StringRef Section,
unsigned TAA, unsigned reserved2, SectionKind K);
friend class MCContext;
public:
/// These are the section type and attributes fields. A MachO section can
/// have only one Type, but can have any of the attributes specified.
enum {
// TypeAndAttributes bitmasks.
SECTION_TYPE = 0x000000FFU,
SECTION_ATTRIBUTES = 0xFFFFFF00U,
// Valid section types.
/// S_REGULAR - Regular section.
S_REGULAR = 0x00U,
/// S_ZEROFILL - Zero fill on demand section.
S_ZEROFILL = 0x01U,
/// S_CSTRING_LITERALS - Section with literal C strings.
S_CSTRING_LITERALS = 0x02U,
/// S_4BYTE_LITERALS - Section with 4 byte literals.
S_4BYTE_LITERALS = 0x03U,
/// S_8BYTE_LITERALS - Section with 8 byte literals.
S_8BYTE_LITERALS = 0x04U,
/// S_LITERAL_POINTERS - Section with pointers to literals.
S_LITERAL_POINTERS = 0x05U,
/// S_NON_LAZY_SYMBOL_POINTERS - Section with non-lazy symbol pointers.
S_NON_LAZY_SYMBOL_POINTERS = 0x06U,
/// S_LAZY_SYMBOL_POINTERS - Section with lazy symbol pointers.
S_LAZY_SYMBOL_POINTERS = 0x07U,
/// S_SYMBOL_STUBS - Section with symbol stubs, byte size of stub in
/// the Reserved2 field.
S_SYMBOL_STUBS = 0x08U,
/// S_MOD_INIT_FUNC_POINTERS - Section with only function pointers for
/// initialization.
S_MOD_INIT_FUNC_POINTERS = 0x09U,
/// S_MOD_TERM_FUNC_POINTERS - Section with only function pointers for
/// termination.
S_MOD_TERM_FUNC_POINTERS = 0x0AU,
/// S_COALESCED - Section contains symbols that are to be coalesced.
S_COALESCED = 0x0BU,
/// S_GB_ZEROFILL - Zero fill on demand section (that can be larger than 4
/// gigabytes).
S_GB_ZEROFILL = 0x0CU,
/// S_INTERPOSING - Section with only pairs of function pointers for
/// interposing.
S_INTERPOSING = 0x0DU,
/// S_16BYTE_LITERALS - Section with only 16 byte literals.
S_16BYTE_LITERALS = 0x0EU,
/// S_DTRACE_DOF - Section contains DTrace Object Format.
S_DTRACE_DOF = 0x0FU,
/// S_LAZY_DYLIB_SYMBOL_POINTERS - Section with lazy symbol pointers to
/// lazy loaded dylibs.
S_LAZY_DYLIB_SYMBOL_POINTERS = 0x10U,
/// S_THREAD_LOCAL_REGULAR - Section with ....
S_THREAD_LOCAL_REGULAR = 0x11U,
/// S_THREAD_LOCAL_ZEROFILL - Thread local zerofill section.
S_THREAD_LOCAL_ZEROFILL = 0x12U,
/// S_THREAD_LOCAL_VARIABLES - Section with thread local variable structure
/// data.
S_THREAD_LOCAL_VARIABLES = 0x13U,
/// S_THREAD_LOCAL_VARIABLE_POINTERS - Section with ....
S_THREAD_LOCAL_VARIABLE_POINTERS = 0x14U,
/// S_THREAD_LOCAL_INIT_FUNCTION_POINTERS - Section with thread local
/// variable initialization pointers to functions.
S_THREAD_LOCAL_INIT_FUNCTION_POINTERS = 0x15U,
LAST_KNOWN_SECTION_TYPE = S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
// Valid section attributes.
/// S_ATTR_PURE_INSTRUCTIONS - Section contains only true machine
/// instructions.
S_ATTR_PURE_INSTRUCTIONS = 1U << 31,
/// S_ATTR_NO_TOC - Section contains coalesced symbols that are not to be
/// in a ranlib table of contents.
S_ATTR_NO_TOC = 1U << 30,
/// S_ATTR_STRIP_STATIC_SYMS - Ok to strip static symbols in this section
/// in files with the MY_DYLDLINK flag.
S_ATTR_STRIP_STATIC_SYMS = 1U << 29,
/// S_ATTR_NO_DEAD_STRIP - No dead stripping.
S_ATTR_NO_DEAD_STRIP = 1U << 28,
/// S_ATTR_LIVE_SUPPORT - Blocks are live if they reference live blocks.
S_ATTR_LIVE_SUPPORT = 1U << 27,
/// S_ATTR_SELF_MODIFYING_CODE - Used with i386 code stubs written on by
/// dyld.
S_ATTR_SELF_MODIFYING_CODE = 1U << 26,
/// S_ATTR_DEBUG - A debug section.
S_ATTR_DEBUG = 1U << 25,
/// S_ATTR_SOME_INSTRUCTIONS - Section contains some machine instructions.
S_ATTR_SOME_INSTRUCTIONS = 1U << 10,
/// S_ATTR_EXT_RELOC - Section has external relocation entries.
S_ATTR_EXT_RELOC = 1U << 9,
/// S_ATTR_LOC_RELOC - Section has local relocation entries.
S_ATTR_LOC_RELOC = 1U << 8
};
StringRef getSegmentName() const {
// SegmentName is not necessarily null terminated!
if (SegmentName[15])
return StringRef(SegmentName, 16);
return StringRef(SegmentName);
}
StringRef getSectionName() const {
// SectionName is not necessarily null terminated!
if (SectionName[15])
return StringRef(SectionName, 16);
return StringRef(SectionName);
}
unsigned getTypeAndAttributes() const { return TypeAndAttributes; }
unsigned getStubSize() const { return Reserved2; }
unsigned getType() const { return TypeAndAttributes & SECTION_TYPE; }
bool hasAttribute(unsigned Value) const {
return (TypeAndAttributes & Value) != 0;
}
/// ParseSectionSpecifier - Parse the section specifier indicated by "Spec".
/// This is a string that can appear after a .section directive in a mach-o
/// flavored .s file. If successful, this fills in the specified Out
/// parameters and returns an empty string. When an invalid section
/// specifier is present, this returns a string indicating the problem.
/// If no TAA was parsed, TAA is not altered, and TAAWasSet becomes false.
static std::string ParseSectionSpecifier(StringRef Spec, // In.
StringRef &Segment, // Out.
StringRef &Section, // Out.
unsigned &TAA, // Out.
bool &TAAParsed, // Out.
unsigned &StubSize); // Out.
virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
raw_ostream &OS) const;
virtual bool UseCodeAlign() const;
virtual bool isVirtualSection() const;
static bool classof(const MCSection *S) {
return S->getVariant() == SV_MachO;
}
static bool classof(const MCSectionMachO *) { return true; }
};
} // end namespace llvm
#endif