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authorDimitry Andric <dim@FreeBSD.org>2017-04-16 16:03:39 +0000
committerDimitry Andric <dim@FreeBSD.org>2017-04-16 16:03:39 +0000
commitd2d3ebb81992e107edf95c1c136d7a342d9b1418 (patch)
treebb1af8fff2b1400cf240e3b2532a1e5d22a121da /ELF/LinkerScript.h
parent16787c9ce0b96aaa669d7fab3a495916b35ce758 (diff)
downloadsrc-d2d3ebb81992e107edf95c1c136d7a342d9b1418.tar.gz
src-d2d3ebb81992e107edf95c1c136d7a342d9b1418.zip
Vendor import of lld trunk r300422:vendor/lld/lld-trunk-r300422
Notes
Notes: svn path=/vendor/lld/dist/; revision=317025 svn path=/vendor/lld/lld-trunk-r300422/; revision=317026; tag=vendor/lld/lld-trunk-r300422
Diffstat (limited to 'ELF/LinkerScript.h')
-rw-r--r--ELF/LinkerScript.h217
1 files changed, 104 insertions, 113 deletions
diff --git a/ELF/LinkerScript.h b/ELF/LinkerScript.h
index 505162f0ab43..04a388efb4e9 100644
--- a/ELF/LinkerScript.h
+++ b/ELF/LinkerScript.h
@@ -15,6 +15,7 @@
#include "Writer.h"
#include "lld/Core/LLVM.h"
#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/MemoryBuffer.h"
@@ -28,45 +29,32 @@ namespace lld {
namespace elf {
class DefinedCommon;
-class ScriptParser;
class SymbolBody;
-template <class ELFT> class InputSectionBase;
-template <class ELFT> class InputSection;
-class OutputSectionBase;
-template <class ELFT> class OutputSectionFactory;
-class InputSectionData;
+class InputSectionBase;
+class InputSection;
+class OutputSection;
+class OutputSectionFactory;
+class InputSectionBase;
+class SectionBase;
+
+struct ExprValue {
+ SectionBase *Sec;
+ uint64_t Val;
+ bool ForceAbsolute;
+
+ ExprValue(SectionBase *Sec, bool ForceAbsolute, uint64_t Val)
+ : Sec(Sec), Val(Val), ForceAbsolute(ForceAbsolute) {}
+ ExprValue(SectionBase *Sec, uint64_t Val) : ExprValue(Sec, false, Val) {}
+ ExprValue(uint64_t Val) : ExprValue(nullptr, Val) {}
+ bool isAbsolute() const { return ForceAbsolute || Sec == nullptr; }
+ uint64_t getValue() const;
+ uint64_t getSecAddr() const;
+};
// This represents an expression in the linker script.
// ScriptParser::readExpr reads an expression and returns an Expr.
-// Later, we evaluate the expression by calling the function
-// with the value of special context variable ".".
-struct Expr {
- std::function<uint64_t(uint64_t)> Val;
- std::function<bool()> IsAbsolute;
-
- // If expression is section-relative the function below is used
- // to get the output section pointer.
- std::function<const OutputSectionBase *()> Section;
-
- uint64_t operator()(uint64_t Dot) const { return Val(Dot); }
- operator bool() const { return (bool)Val; }
-
- Expr(std::function<uint64_t(uint64_t)> Val, std::function<bool()> IsAbsolute,
- std::function<const OutputSectionBase *()> Section)
- : Val(Val), IsAbsolute(IsAbsolute), Section(Section) {}
- template <typename T>
- Expr(T V) : Expr(V, [] { return true; }, [] { return nullptr; }) {}
- Expr() : Expr(nullptr) {}
-};
-
-// Parses a linker script. Calling this function updates
-// Config and ScriptConfig.
-void readLinkerScript(MemoryBufferRef MB);
-
-// Parses a version script.
-void readVersionScript(MemoryBufferRef MB);
-
-void readDynamicList(MemoryBufferRef MB);
+// Later, we evaluate the expression by calling the function.
+typedef std::function<ExprValue()> Expr;
// This enum is used to implement linker script SECTIONS command.
// https://sourceware.org/binutils/docs/ld/SECTIONS.html#SECTIONS
@@ -80,16 +68,13 @@ enum SectionsCommandKind {
struct BaseCommand {
BaseCommand(int K) : Kind(K) {}
-
- virtual ~BaseCommand() = default;
-
int Kind;
};
// This represents ". = <expr>" or "<symbol> = <expr>".
struct SymbolAssignment : BaseCommand {
- SymbolAssignment(StringRef Name, Expr E)
- : BaseCommand(AssignmentKind), Name(Name), Expression(E) {}
+ SymbolAssignment(StringRef Name, Expr E, std::string Loc)
+ : BaseCommand(AssignmentKind), Name(Name), Expression(E), Location(Loc) {}
static bool classof(const BaseCommand *C);
@@ -103,6 +88,9 @@ struct SymbolAssignment : BaseCommand {
// Command attributes for PROVIDE, HIDDEN and PROVIDE_HIDDEN.
bool Provide = false;
bool Hidden = false;
+
+ // Holds file name and line number for error reporting.
+ std::string Location;
};
// Linker scripts allow additional constraints to be put on ouput sections.
@@ -111,22 +99,37 @@ struct SymbolAssignment : BaseCommand {
// with ONLY_IF_RW is created if all input sections are RW.
enum class ConstraintKind { NoConstraint, ReadOnly, ReadWrite };
+// This struct is used to represent the location and size of regions of
+// target memory. Instances of the struct are created by parsing the
+// MEMORY command.
+struct MemoryRegion {
+ std::string Name;
+ uint64_t Origin;
+ uint64_t Length;
+ uint64_t Offset;
+ uint32_t Flags;
+ uint32_t NegFlags;
+};
+
struct OutputSectionCommand : BaseCommand {
OutputSectionCommand(StringRef Name)
: BaseCommand(OutputSectionKind), Name(Name) {}
static bool classof(const BaseCommand *C);
+ OutputSection *Sec = nullptr;
+ MemoryRegion *MemRegion = nullptr;
StringRef Name;
Expr AddrExpr;
Expr AlignExpr;
Expr LMAExpr;
Expr SubalignExpr;
- std::vector<std::unique_ptr<BaseCommand>> Commands;
+ std::vector<BaseCommand *> Commands;
std::vector<StringRef> Phdrs;
- uint32_t Filler = 0;
+ llvm::Optional<uint32_t> Filler;
ConstraintKind Constraint = ConstraintKind::NoConstraint;
std::string Location;
+ std::string MemoryRegionName;
};
// This struct represents one section match pattern in SECTIONS() command.
@@ -154,7 +157,7 @@ struct InputSectionDescription : BaseCommand {
// will be associated with this InputSectionDescription.
std::vector<SectionPattern> SectionPatterns;
- std::vector<InputSectionData *> Sections;
+ std::vector<InputSectionBase *> Sections;
};
// Represents an ASSERT().
@@ -187,25 +190,10 @@ struct PhdrsCommand {
Expr LMAExpr;
};
-class LinkerScriptBase {
-protected:
- ~LinkerScriptBase() = default;
-
-public:
- virtual uint64_t getHeaderSize() = 0;
- virtual uint64_t getSymbolValue(const Twine &Loc, StringRef S) = 0;
- virtual bool isDefined(StringRef S) = 0;
- virtual bool isAbsolute(StringRef S) = 0;
- virtual const OutputSectionBase *getSymbolSection(StringRef S) = 0;
- virtual const OutputSectionBase *getOutputSection(const Twine &Loc,
- StringRef S) = 0;
- virtual uint64_t getOutputSectionSize(StringRef S) = 0;
-};
-
// ScriptConfiguration holds linker script parse results.
struct ScriptConfiguration {
// Used to assign addresses to sections.
- std::vector<std::unique_ptr<BaseCommand>> Commands;
+ std::vector<BaseCommand *> Commands;
// Used to assign sections to headers.
std::vector<PhdrsCommand> PhdrsCommands;
@@ -215,20 +203,60 @@ struct ScriptConfiguration {
// List of section patterns specified with KEEP commands. They will
// be kept even if they are unused and --gc-sections is specified.
std::vector<InputSectionDescription *> KeptSections;
+
+ // A map from memory region name to a memory region descriptor.
+ llvm::DenseMap<llvm::StringRef, MemoryRegion> MemoryRegions;
+
+ // A list of symbols referenced by the script.
+ std::vector<llvm::StringRef> ReferencedSymbols;
};
-extern ScriptConfiguration *ScriptConfig;
+class LinkerScript {
+protected:
+ void assignSymbol(SymbolAssignment *Cmd, bool InSec);
+ void setDot(Expr E, const Twine &Loc, bool InSec);
+
+ std::vector<InputSectionBase *>
+ computeInputSections(const InputSectionDescription *);
+
+ std::vector<InputSectionBase *>
+ createInputSectionList(OutputSectionCommand &Cmd);
+
+ std::vector<size_t> getPhdrIndices(StringRef SectionName);
+ size_t getPhdrIndex(const Twine &Loc, StringRef PhdrName);
+
+ MemoryRegion *findMemoryRegion(OutputSectionCommand *Cmd);
+
+ void switchTo(OutputSection *Sec);
+ void flush();
+ void output(InputSection *Sec);
+ void process(BaseCommand &Base);
-// This is a runner of the linker script.
-template <class ELFT> class LinkerScript final : public LinkerScriptBase {
- typedef typename ELFT::uint uintX_t;
+ OutputSection *Aether;
+ bool ErrorOnMissingSection = false;
+
+ uint64_t Dot;
+ uint64_t ThreadBssOffset = 0;
+
+ std::function<uint64_t()> LMAOffset;
+ OutputSection *CurOutSec = nullptr;
+ MemoryRegion *CurMemRegion = nullptr;
+
+ llvm::DenseSet<OutputSection *> AlreadyOutputOS;
+ llvm::DenseSet<InputSectionBase *> AlreadyOutputIS;
public:
- LinkerScript();
- ~LinkerScript();
+ bool hasPhdrsCommands() { return !Opt.PhdrsCommands.empty(); }
+ uint64_t getDot() { return Dot; }
+ OutputSection *getOutputSection(const Twine &Loc, StringRef S);
+ uint64_t getOutputSectionSize(StringRef S);
+ void discard(ArrayRef<InputSectionBase *> V);
- void processCommands(OutputSectionFactory<ELFT> &Factory);
- void addOrphanSections(OutputSectionFactory<ELFT> &Factory);
+ ExprValue getSymbolValue(const Twine &Loc, StringRef S);
+ bool isDefined(StringRef S);
+
+ std::vector<OutputSection *> *OutputSections;
+ void addOrphanSections(OutputSectionFactory &Factory);
void removeEmptyCommands();
void adjustSectionsBeforeSorting();
void adjustSectionsAfterSorting();
@@ -236,61 +264,24 @@ public:
std::vector<PhdrEntry> createPhdrs();
bool ignoreInterpSection();
- uint32_t getFiller(StringRef Name);
- void writeDataBytes(StringRef Name, uint8_t *Buf);
+ llvm::Optional<uint32_t> getFiller(StringRef Name);
bool hasLMA(StringRef Name);
- bool shouldKeep(InputSectionBase<ELFT> *S);
+ bool shouldKeep(InputSectionBase *S);
void assignOffsets(OutputSectionCommand *Cmd);
void placeOrphanSections();
+ void processNonSectionCommands();
void assignAddresses(std::vector<PhdrEntry> &Phdrs);
- bool hasPhdrsCommands();
- uint64_t getHeaderSize() override;
- uint64_t getSymbolValue(const Twine &Loc, StringRef S) override;
- bool isDefined(StringRef S) override;
- bool isAbsolute(StringRef S) override;
- const OutputSectionBase *getSymbolSection(StringRef S) override;
- const OutputSectionBase *getOutputSection(const Twine &Loc,
- StringRef S) override;
- uint64_t getOutputSectionSize(StringRef S) override;
-
- std::vector<OutputSectionBase *> *OutputSections;
-
int getSectionIndex(StringRef Name);
-private:
- void computeInputSections(InputSectionDescription *);
-
- void addSection(OutputSectionFactory<ELFT> &Factory,
- InputSectionBase<ELFT> *Sec, StringRef Name);
- void discard(ArrayRef<InputSectionBase<ELFT> *> V);
-
- std::vector<InputSectionBase<ELFT> *>
- createInputSectionList(OutputSectionCommand &Cmd);
-
- // "ScriptConfig" is a bit too long, so define a short name for it.
- ScriptConfiguration &Opt = *ScriptConfig;
-
- std::vector<size_t> getPhdrIndices(StringRef SectionName);
- size_t getPhdrIndex(const Twine &Loc, StringRef PhdrName);
+ void writeDataBytes(StringRef Name, uint8_t *Buf);
+ void addSymbol(SymbolAssignment *Cmd);
+ void processCommands(OutputSectionFactory &Factory);
- uintX_t Dot;
- uintX_t LMAOffset = 0;
- OutputSectionBase *CurOutSec = nullptr;
- uintX_t ThreadBssOffset = 0;
- void switchTo(OutputSectionBase *Sec);
- void flush();
- void output(InputSection<ELFT> *Sec);
- void process(BaseCommand &Base);
- llvm::DenseSet<OutputSectionBase *> AlreadyOutputOS;
- llvm::DenseSet<InputSectionData *> AlreadyOutputIS;
+ // Parsed linker script configurations are set to this struct.
+ ScriptConfiguration Opt;
};
-// Variable template is a C++14 feature, so we can't template
-// a global variable. Use a struct to workaround.
-template <class ELFT> struct Script { static LinkerScript<ELFT> *X; };
-template <class ELFT> LinkerScript<ELFT> *Script<ELFT>::X;
-
-extern LinkerScriptBase *ScriptBase;
+extern LinkerScript *Script;
} // end namespace elf
} // end namespace lld