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-rw-r--r--llvm/lib/MC/MCSectionMachO.cpp281
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diff --git a/llvm/lib/MC/MCSectionMachO.cpp b/llvm/lib/MC/MCSectionMachO.cpp
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+//===- lib/MC/MCSectionMachO.cpp - MachO Code Section Representation ------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cctype>
+using namespace llvm;
+
+/// SectionTypeDescriptors - These are strings that describe the various section
+/// types. This *must* be kept in order with and stay synchronized with the
+/// section type list.
+static constexpr struct {
+ StringLiteral AssemblerName, EnumName;
+} SectionTypeDescriptors[MachO::LAST_KNOWN_SECTION_TYPE + 1] = {
+ {StringLiteral("regular"), StringLiteral("S_REGULAR")}, // 0x00
+ {StringLiteral(""), StringLiteral("S_ZEROFILL")}, // 0x01
+ {StringLiteral("cstring_literals"),
+ StringLiteral("S_CSTRING_LITERALS")}, // 0x02
+ {StringLiteral("4byte_literals"),
+ StringLiteral("S_4BYTE_LITERALS")}, // 0x03
+ {StringLiteral("8byte_literals"),
+ StringLiteral("S_8BYTE_LITERALS")}, // 0x04
+ {StringLiteral("literal_pointers"),
+ StringLiteral("S_LITERAL_POINTERS")}, // 0x05
+ {StringLiteral("non_lazy_symbol_pointers"),
+ StringLiteral("S_NON_LAZY_SYMBOL_POINTERS")}, // 0x06
+ {StringLiteral("lazy_symbol_pointers"),
+ StringLiteral("S_LAZY_SYMBOL_POINTERS")}, // 0x07
+ {StringLiteral("symbol_stubs"), StringLiteral("S_SYMBOL_STUBS")}, // 0x08
+ {StringLiteral("mod_init_funcs"),
+ StringLiteral("S_MOD_INIT_FUNC_POINTERS")}, // 0x09
+ {StringLiteral("mod_term_funcs"),
+ StringLiteral("S_MOD_TERM_FUNC_POINTERS")}, // 0x0A
+ {StringLiteral("coalesced"), StringLiteral("S_COALESCED")}, // 0x0B
+ {StringLiteral("") /*FIXME??*/, StringLiteral("S_GB_ZEROFILL")}, // 0x0C
+ {StringLiteral("interposing"), StringLiteral("S_INTERPOSING")}, // 0x0D
+ {StringLiteral("16byte_literals"),
+ StringLiteral("S_16BYTE_LITERALS")}, // 0x0E
+ {StringLiteral("") /*FIXME??*/, StringLiteral("S_DTRACE_DOF")}, // 0x0F
+ {StringLiteral("") /*FIXME??*/,
+ StringLiteral("S_LAZY_DYLIB_SYMBOL_POINTERS")}, // 0x10
+ {StringLiteral("thread_local_regular"),
+ StringLiteral("S_THREAD_LOCAL_REGULAR")}, // 0x11
+ {StringLiteral("thread_local_zerofill"),
+ StringLiteral("S_THREAD_LOCAL_ZEROFILL")}, // 0x12
+ {StringLiteral("thread_local_variables"),
+ StringLiteral("S_THREAD_LOCAL_VARIABLES")}, // 0x13
+ {StringLiteral("thread_local_variable_pointers"),
+ StringLiteral("S_THREAD_LOCAL_VARIABLE_POINTERS")}, // 0x14
+ {StringLiteral("thread_local_init_function_pointers"),
+ StringLiteral("S_THREAD_LOCAL_INIT_FUNCTION_POINTERS")}, // 0x15
+};
+
+/// SectionAttrDescriptors - This is an array of descriptors for section
+/// attributes. Unlike the SectionTypeDescriptors, this is not directly indexed
+/// by attribute, instead it is searched.
+static constexpr struct {
+ unsigned AttrFlag;
+ StringLiteral AssemblerName, EnumName;
+} SectionAttrDescriptors[] = {
+#define ENTRY(ASMNAME, ENUM) \
+ { MachO::ENUM, StringLiteral(ASMNAME), StringLiteral(#ENUM) },
+ENTRY("pure_instructions", S_ATTR_PURE_INSTRUCTIONS)
+ENTRY("no_toc", S_ATTR_NO_TOC)
+ENTRY("strip_static_syms", S_ATTR_STRIP_STATIC_SYMS)
+ENTRY("no_dead_strip", S_ATTR_NO_DEAD_STRIP)
+ENTRY("live_support", S_ATTR_LIVE_SUPPORT)
+ENTRY("self_modifying_code", S_ATTR_SELF_MODIFYING_CODE)
+ENTRY("debug", S_ATTR_DEBUG)
+ENTRY("" /*FIXME*/, S_ATTR_SOME_INSTRUCTIONS)
+ENTRY("" /*FIXME*/, S_ATTR_EXT_RELOC)
+ENTRY("" /*FIXME*/, S_ATTR_LOC_RELOC)
+#undef ENTRY
+ { 0, StringLiteral("none"), StringLiteral("") }, // used if section has no attributes but has a stub size
+};
+
+MCSectionMachO::MCSectionMachO(StringRef Segment, StringRef Section,
+ unsigned TAA, unsigned reserved2, SectionKind K,
+ MCSymbol *Begin)
+ : MCSection(SV_MachO, K, Begin), TypeAndAttributes(TAA),
+ Reserved2(reserved2) {
+ assert(Segment.size() <= 16 && Section.size() <= 16 &&
+ "Segment or section string too long");
+ for (unsigned i = 0; i != 16; ++i) {
+ if (i < Segment.size())
+ SegmentName[i] = Segment[i];
+ else
+ SegmentName[i] = 0;
+
+ if (i < Section.size())
+ SectionName[i] = Section[i];
+ else
+ SectionName[i] = 0;
+ }
+}
+
+void MCSectionMachO::PrintSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
+ raw_ostream &OS,
+ const MCExpr *Subsection) const {
+ OS << "\t.section\t" << getSegmentName() << ',' << getSectionName();
+
+ // Get the section type and attributes.
+ unsigned TAA = getTypeAndAttributes();
+ if (TAA == 0) {
+ OS << '\n';
+ return;
+ }
+
+ MachO::SectionType SectionType = getType();
+ assert(SectionType <= MachO::LAST_KNOWN_SECTION_TYPE &&
+ "Invalid SectionType specified!");
+
+ if (!SectionTypeDescriptors[SectionType].AssemblerName.empty()) {
+ OS << ',';
+ OS << SectionTypeDescriptors[SectionType].AssemblerName;
+ } else {
+ // If we have no name for the attribute, stop here.
+ OS << '\n';
+ return;
+ }
+
+ // If we don't have any attributes, we're done.
+ unsigned SectionAttrs = TAA & MachO::SECTION_ATTRIBUTES;
+ if (SectionAttrs == 0) {
+ // If we have a S_SYMBOL_STUBS size specified, print it along with 'none' as
+ // the attribute specifier.
+ if (Reserved2 != 0)
+ OS << ",none," << Reserved2;
+ OS << '\n';
+ return;
+ }
+
+ // Check each attribute to see if we have it.
+ char Separator = ',';
+ for (unsigned i = 0;
+ SectionAttrs != 0 && SectionAttrDescriptors[i].AttrFlag;
+ ++i) {
+ // Check to see if we have this attribute.
+ if ((SectionAttrDescriptors[i].AttrFlag & SectionAttrs) == 0)
+ continue;
+
+ // Yep, clear it and print it.
+ SectionAttrs &= ~SectionAttrDescriptors[i].AttrFlag;
+
+ OS << Separator;
+ if (!SectionAttrDescriptors[i].AssemblerName.empty())
+ OS << SectionAttrDescriptors[i].AssemblerName;
+ else
+ OS << "<<" << SectionAttrDescriptors[i].EnumName << ">>";
+ Separator = '+';
+ }
+
+ assert(SectionAttrs == 0 && "Unknown section attributes!");
+
+ // If we have a S_SYMBOL_STUBS size specified, print it.
+ if (Reserved2 != 0)
+ OS << ',' << Reserved2;
+ OS << '\n';
+}
+
+bool MCSectionMachO::UseCodeAlign() const {
+ return hasAttribute(MachO::S_ATTR_PURE_INSTRUCTIONS);
+}
+
+bool MCSectionMachO::isVirtualSection() const {
+ return (getType() == MachO::S_ZEROFILL ||
+ getType() == MachO::S_GB_ZEROFILL ||
+ getType() == MachO::S_THREAD_LOCAL_ZEROFILL);
+}
+
+/// 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.
+std::string MCSectionMachO::ParseSectionSpecifier(StringRef Spec, // In.
+ StringRef &Segment, // Out.
+ StringRef &Section, // Out.
+ unsigned &TAA, // Out.
+ bool &TAAParsed, // Out.
+ unsigned &StubSize) { // Out.
+ TAAParsed = false;
+
+ SmallVector<StringRef, 5> SplitSpec;
+ Spec.split(SplitSpec, ',');
+ // Remove leading and trailing whitespace.
+ auto GetEmptyOrTrim = [&SplitSpec](size_t Idx) -> StringRef {
+ return SplitSpec.size() > Idx ? SplitSpec[Idx].trim() : StringRef();
+ };
+ Segment = GetEmptyOrTrim(0);
+ Section = GetEmptyOrTrim(1);
+ StringRef SectionType = GetEmptyOrTrim(2);
+ StringRef Attrs = GetEmptyOrTrim(3);
+ StringRef StubSizeStr = GetEmptyOrTrim(4);
+
+ // Verify that the segment is present and not too long.
+ if (Segment.empty() || Segment.size() > 16)
+ return "mach-o section specifier requires a segment whose length is "
+ "between 1 and 16 characters";
+
+ // Verify that the section is present and not too long.
+ if (Section.empty())
+ return "mach-o section specifier requires a segment and section "
+ "separated by a comma";
+
+ if (Section.size() > 16)
+ return "mach-o section specifier requires a section whose length is "
+ "between 1 and 16 characters";
+
+ // If there is no comma after the section, we're done.
+ TAA = 0;
+ StubSize = 0;
+ if (SectionType.empty())
+ return "";
+
+ // Figure out which section type it is.
+ auto TypeDescriptor = std::find_if(
+ std::begin(SectionTypeDescriptors), std::end(SectionTypeDescriptors),
+ [&](decltype(*SectionTypeDescriptors) &Descriptor) {
+ return SectionType == Descriptor.AssemblerName;
+ });
+
+ // If we didn't find the section type, reject it.
+ if (TypeDescriptor == std::end(SectionTypeDescriptors))
+ return "mach-o section specifier uses an unknown section type";
+
+ // Remember the TypeID.
+ TAA = TypeDescriptor - std::begin(SectionTypeDescriptors);
+ TAAParsed = true;
+
+ // If we have no comma after the section type, there are no attributes.
+ if (Attrs.empty()) {
+ // S_SYMBOL_STUBS always require a symbol stub size specifier.
+ if (TAA == MachO::S_SYMBOL_STUBS)
+ return "mach-o section specifier of type 'symbol_stubs' requires a size "
+ "specifier";
+ return "";
+ }
+
+ // The attribute list is a '+' separated list of attributes.
+ SmallVector<StringRef, 1> SectionAttrs;
+ Attrs.split(SectionAttrs, '+', /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+
+ for (StringRef &SectionAttr : SectionAttrs) {
+ auto AttrDescriptorI = std::find_if(
+ std::begin(SectionAttrDescriptors), std::end(SectionAttrDescriptors),
+ [&](decltype(*SectionAttrDescriptors) &Descriptor) {
+ return SectionAttr.trim() == Descriptor.AssemblerName;
+ });
+ if (AttrDescriptorI == std::end(SectionAttrDescriptors))
+ return "mach-o section specifier has invalid attribute";
+
+ TAA |= AttrDescriptorI->AttrFlag;
+ }
+
+ // Okay, we've parsed the section attributes, see if we have a stub size spec.
+ if (StubSizeStr.empty()) {
+ // S_SYMBOL_STUBS always require a symbol stub size specifier.
+ if (TAA == MachO::S_SYMBOL_STUBS)
+ return "mach-o section specifier of type 'symbol_stubs' requires a size "
+ "specifier";
+ return "";
+ }
+
+ // If we have a stub size spec, we must have a sectiontype of S_SYMBOL_STUBS.
+ if ((TAA & MachO::SECTION_TYPE) != MachO::S_SYMBOL_STUBS)
+ return "mach-o section specifier cannot have a stub size specified because "
+ "it does not have type 'symbol_stubs'";
+
+ // Convert the stub size from a string to an integer.
+ if (StubSizeStr.getAsInteger(0, StubSize))
+ return "mach-o section specifier has a malformed stub size";
+
+ return "";
+}
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