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diff --git a/3rdparty/asmjit/asmjit/core/codeholder.h b/3rdparty/asmjit/asmjit/core/codeholder.h new file mode 100644 index 00000000000..f8dcfb7b52a --- /dev/null +++ b/3rdparty/asmjit/asmjit/core/codeholder.h @@ -0,0 +1,1318 @@ +// This file is part of AsmJit project <https://asmjit.com> +// +// See <asmjit/core.h> or LICENSE.md for license and copyright information +// SPDX-License-Identifier: Zlib + +#ifndef ASMJIT_CORE_CODEHOLDER_H_INCLUDED +#define ASMJIT_CORE_CODEHOLDER_H_INCLUDED + +#include <asmjit/core/archtraits.h> +#include <asmjit/core/codebuffer.h> +#include <asmjit/core/errorhandler.h> +#include <asmjit/core/fixup.h> +#include <asmjit/core/operand.h> +#include <asmjit/core/string.h> +#include <asmjit/core/target.h> +#include <asmjit/support/arena.h> +#include <asmjit/support/arenahash.h> +#include <asmjit/support/arenapool.h> +#include <asmjit/support/arenastring.h> +#include <asmjit/support/arenatree.h> +#include <asmjit/support/arenavector.h> +#include <asmjit/support/span.h> +#include <asmjit/support/support.h> + +ASMJIT_BEGIN_NAMESPACE + +//! \addtogroup asmjit_core +//! \{ + +class BaseEmitter; +class CodeHolder; +class LabelEntry; +class Logger; + +//! Operator type that can be used within an \ref Expression. +enum class ExpressionOpType : uint8_t { + //! Addition. + kAdd = 0, + //! Subtraction. + kSub = 1, + //! Multiplication + kMul = 2, + //! Logical left shift. + kSll = 3, + //! Logical right shift. + kSrl = 4, + //! Arithmetic right shift. + kSra = 5 +}; + +//! Value type that can be used within an \ref Expression. +enum class ExpressionValueType : uint8_t { + //! No value or invalid. + kNone = 0, + //! Value is 64-bit unsigned integer (constant). + kConstant = 1, + //! Value is \ref LabelEntry, which references a \ref Label. + kLabel = 2, + //! Value is \ref Expression + kExpression = 3 +}; + +//! Expression node that can reference constants, labels, and another expressions. +struct Expression { + //! Expression value. + union Value { + //! Constant. + uint64_t constant; + //! Pointer to another expression. + Expression* expression; + //! Label identifier + uint32_t label_id; + }; + + //! \name Members + //! \{ + + //! Operation type. + ExpressionOpType op_type; + //! Value types of \ref value. + ExpressionValueType value_type[2]; + //! Reserved for future use, should be initialized to zero. + uint8_t reserved[5]; + //! Expression left and right values. + Value value[2]; + + //! \} + + //! \name Accessors + //! \{ + + //! Resets the whole expression. + //! + //! Changes both values to \ref ExpressionValueType::kNone. + ASMJIT_INLINE_NODEBUG void reset() noexcept { *this = Expression{}; } + + //! Sets the value type at `index` to \ref ExpressionValueType::kConstant and its content to `constant`. + ASMJIT_INLINE_NODEBUG void set_value_as_constant(size_t index, uint64_t constant) noexcept { + value_type[index] = ExpressionValueType::kConstant; + value[index].constant = constant; + } + + //! Sets the value type at `index` to \ref ExpressionValueType::kLabel and its content to `label_entry`. + ASMJIT_INLINE_NODEBUG void set_value_as_label_id(size_t index, uint32_t label_id) noexcept { + value_type[index] = ExpressionValueType::kLabel; + value[index].label_id = label_id; + } + + //! Sets the value type at `index` to \ref ExpressionValueType::kExpression and its content to `expression`. + ASMJIT_INLINE_NODEBUG void set_value_as_expression(size_t index, Expression* expression) noexcept { + value_type[index] = ExpressionValueType::kExpression; + value[index].expression = expression; + } + + //! \} +}; + +//! Relocation type. +enum class RelocType : uint32_t { + //! None/deleted (no relocation). + kNone = 0, + //! Expression evaluation, `_payload` is pointer to `Expression`. + kExpression = 1, + //! Relative relocation from one section to another. + kSectionRelative = 2, + //! Relocate absolute to absolute. + kAbsToAbs = 3, + //! Relocate relative to absolute. + kRelToAbs = 4, + //! Relocate absolute to relative. + kAbsToRel = 5, + //! Relocate absolute to relative or use trampoline. + kX64AddressEntry = 6 +}; + +//! Type of the \ref Label. +enum class LabelType : uint8_t { + //! Anonymous label that can optionally have a name, which is only used for debugging purposes. + kAnonymous = 0u, + //! Local label (always has parent_id). + kLocal = 1u, + //! Global label (never has parent_id). + kGlobal = 2u, + //! External label (references an external symbol). + kExternal = 3u, + + //! Maximum value of `LabelType`. + kMaxValue = kExternal +}; + +//! Label flags describe some details about labels used by \ref LabelEntry, mostly for AsmJit's own use. +enum class LabelFlags : uint8_t { + //! No flags. + kNone = 0x00u, + //! Label has associated extra data with it that it owns. + kHasOwnExtraData = 0x01u, + //! Label has a name. + kHasName = 0x02u, + //! Label has a parent (only a local label can have a parent). + kHasParent = 0x04u +}; +ASMJIT_DEFINE_ENUM_FLAGS(LabelFlags) + +//! Section flags, used by \ref Section. +enum class SectionFlags : uint32_t { + //! No flags. + kNone = 0, + //! Executable (.text sections). + kExecutable = 0x0001u, + //! Read-only (.text and .data sections). + kReadOnly = 0x0002u, + //! Zero initialized by the loader (BSS). + kZeroInitialized = 0x0004u, + //! Info / comment flag. + kComment = 0x0008u, + //! Section is built in and created by default (.text section). + kBuiltIn = 0x4000u, + //! Section created implicitly, can be deleted by \ref Target. + kImplicit = 0x8000u +}; +ASMJIT_DEFINE_ENUM_FLAGS(SectionFlags) + +//! Flags that can be used with \ref CodeHolder::copy_section_data() and \ref CodeHolder::copy_flattened_data(). +enum class CopySectionFlags : uint32_t { + //! No flags. + kNone = 0, + + //! If virtual size of a section is greater than the size of its \ref CodeBuffer then all bytes between the buffer + //! size and virtual size will be zeroed. If this option is not set then those bytes would be left as is, which + //! means that if the user didn't initialize them they would have a previous content, which may be unwanted. + kPadSectionBuffer = 0x00000001u, + + //! Clears the target buffer if the flattened data is less than the destination size. This option works + //! only with \ref CodeHolder::copy_flattened_data() as it processes multiple sections. It is ignored by + //! \ref CodeHolder::copy_section_data(). + kPadTargetBuffer = 0x00000002u +}; +ASMJIT_DEFINE_ENUM_FLAGS(CopySectionFlags) + +//! Base class for both \ref Section and \ref LabelEntry::ExtraData. +class SectionOrLabelEntryExtraHeader { +public: + //! \name Members + //! \{ + + //! Section id - describes either a section where a \ref Label is bound or it's a real section id of \ref Section. + uint32_t _section_id; + + //! Internal label type is only used by \ref LabelEntry::ExtraData. \ref Section always leaves this field zero, + //! which describes an anonymous label. Anonymous labels are default and always used when there is no + //! \ref LabelEntry::ExtraData + LabelType _internal_label_type; + + //! Internal label flags, used by \ref LabelEntry::ExtraData. \ref Section doesn't use these flags and sets them + //! to zero. + LabelFlags _internal_label_flags; + + //! Internal data used freely by \ref Section and \ref LabelEntry::ExtraData. + uint16_t _internal_uint16_data; + + //! \} +}; + +//! Section entry. +class Section : public SectionOrLabelEntryExtraHeader { +public: + //! \name Members + //! \{ + + //! Section alignment requirements (0 if no requirements). + uint32_t _alignment; + //! Order (lower value means higher priority). + int32_t _order; + //! Offset of this section from base-address. + uint64_t _offset; + //! Virtual size of the section (zero initialized sections). + uint64_t _virtual_size; + //! Section name (max 35 characters, PE allows max 8). + FixedString<Globals::kMaxSectionNameSize + 1> _name; + //! Code or data buffer. + CodeBuffer _buffer; + + //! \} + + //! \name Accessors + //! \{ + + //! Returns the section id. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t section_id() const noexcept { return _section_id; } + + //! Returns the section name, as a null terminated string. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const char* name() const noexcept { return _name.str; } + + //! Returns the section data. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint8_t* data() noexcept { return _buffer.data(); } + + //! \overload + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const uint8_t* data() const noexcept { return _buffer.data(); } + + //! Returns the section flags. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG SectionFlags flags() const noexcept { return SectionFlags(_internal_uint16_data); } + + //! Tests whether the section has the given `flag`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_flag(SectionFlags flag) const noexcept { return Support::test(_internal_uint16_data, uint32_t(flag)); } + + //! Assigns `flags` to the section (replaces all existing flags). + ASMJIT_INLINE_NODEBUG void assign_flags(SectionFlags flags) noexcept { _internal_uint16_data = uint16_t(flags); } + + //! Adds `flags` to the section flags. + ASMJIT_INLINE_NODEBUG void add_flags(SectionFlags flags) noexcept { _internal_uint16_data = uint16_t(_internal_uint16_data | uint32_t(flags)); } + + //! Removes `flags` from the section flags. + ASMJIT_INLINE_NODEBUG void clear_flags(SectionFlags flags) noexcept { _internal_uint16_data = uint16_t(_internal_uint16_data | ~uint32_t(flags)); } + + //! Returns the minimum section alignment + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t alignment() const noexcept { return _alignment; } + + //! Sets the minimum section alignment + ASMJIT_INLINE_NODEBUG void set_alignment(uint32_t alignment) noexcept { _alignment = alignment; } + + //! Returns the section order, which has a higher priority than section id. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG int32_t order() const noexcept { return _order; } + + //! Returns the section offset, relative to base. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t offset() const noexcept { return _offset; } + + //! Set the section offset. + //! + //! \note If the section's offset hasn't been assigned, the returned value would be \ref Globals::kNoSectionOffset. + ASMJIT_INLINE_NODEBUG void set_offset(uint64_t offset) noexcept { _offset = offset; } + + //! Returns whether the section's offset has been already assigned. + //! + //! This is true for the first built-in .text section and for all sections that have been flattened. + ASMJIT_INLINE_NODEBUG bool has_offset() const noexcept { return _offset != Globals::kNoSectionOffset; } + + //! Returns the virtual size of the section. + //! + //! Virtual size is initially zero and is never changed by AsmJit. It's normal if virtual size is smaller than + //! size returned by `buffer_size()` as the buffer stores real data emitted by assemblers or appended by users. + //! + //! Use `real_size()` to get the real and final size of this section. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t virtual_size() const noexcept { return _virtual_size; } + + //! Sets the virtual size of the section. + ASMJIT_INLINE_NODEBUG void set_virtual_size(uint64_t virtual_size) noexcept { _virtual_size = virtual_size; } + + //! Returns the buffer size of the section. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG size_t buffer_size() const noexcept { return _buffer.size(); } + + //! Returns the real size of the section calculated from virtual and buffer sizes. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t real_size() const noexcept { return Support::max<uint64_t>(virtual_size(), buffer_size()); } + + //! Returns the `CodeBuffer` used by this section. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG CodeBuffer& buffer() noexcept { return _buffer; } + + //! Returns the `CodeBuffer` used by this section (const). + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const CodeBuffer& buffer() const noexcept { return _buffer; } + + //! \} +}; + +//! Entry in an address table. +class AddressTableEntry : public ArenaTreeNodeT<AddressTableEntry> { +public: + ASMJIT_NONCOPYABLE(AddressTableEntry) + + //! \name Members + //! \{ + + //! Address. + uint64_t _address; + //! Slot. + uint32_t _slot; + + //! \} + + //! \name Construction & Destruction + //! \{ + + ASMJIT_INLINE_NODEBUG explicit AddressTableEntry(uint64_t address) noexcept + : _address(address), + _slot(0xFFFFFFFFu) {} + + //! \} + + //! \name Accessors + //! \{ + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t address() const noexcept { return _address; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t slot() const noexcept { return _slot; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_assigned_slot() const noexcept { return _slot != 0xFFFFFFFFu; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool operator<(const AddressTableEntry& other) const noexcept { return _address < other._address; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool operator>(const AddressTableEntry& other) const noexcept { return _address > other._address; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool operator<(uint64_t query_address) const noexcept { return _address < query_address; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool operator>(uint64_t query_address) const noexcept { return _address > query_address; } + + //! \} +}; + +//! Relocation entry. +struct RelocEntry { + //! \name Members + //! \{ + + //! Relocation id. + uint32_t _id; + //! Type of the relocation. + RelocType _reloc_type; + //! Format of the relocated value. + OffsetFormat _format; + //! Source section id. + uint32_t _source_section_id; + //! Target section id. + uint32_t _target_section_id; + //! Source offset (relative to start of the section). + uint64_t _source_offset; + //! Payload (target offset, target address, expression, etc). + uint64_t _payload; + + //! \} + + //! \name Accessors + //! \{ + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t id() const noexcept { return _id; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG RelocType reloc_type() const noexcept { return _reloc_type; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const OffsetFormat& format() const noexcept { return _format; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t source_section_id() const noexcept { return _source_section_id; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t target_section_id() const noexcept { return _target_section_id; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t source_offset() const noexcept { return _source_offset; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t payload() const noexcept { return _payload; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Expression* payload_as_expression() const noexcept { + return reinterpret_cast<Expression*>(uintptr_t(_payload)); + } + + //! \} +}; + +//! Label entry provides data stored by \ref CodeHolder for each \ref Label. +//! +//! Label entry is used mostly internall by AsmJit, but it's possibly to use it to query various information about +//! a label. For example to get its type, flags, name, and fixups (if the label is not bound) or offset (if the label +//! is bound). +//! +//! To make the entry small, it's currently split into two data structures - \ref LabelEntry, which is stored in an +//! array as a value, and \ref LabelEntry::ExtraData, which can be pointed to via \ref LabelEntry::_object_data. Extra +//! data of unnamed anonymous labels is shared (and immutable), thus all unnamed anonymous labels would only use +//! \ref LabelEntry (16 bytes per label). +class LabelEntry { +public: + //! Contains extra data that is only created when the label is not anonymous or has a name. + struct ExtraData : public SectionOrLabelEntryExtraHeader { + //! Label parent id or zero. + uint32_t _parent_id; + //! Label name length. + uint32_t _name_size; + + //! Returns a name associated with this extra data - a valid pointer is only returned when the label has a name, which + //! is marked by \ref LabelFlags::kHasName flag. + ASMJIT_INLINE_NODEBUG const char* name() const noexcept { return Support::offset_ptr<char>(this, sizeof(ExtraData)); } + }; + + //! \name Members + //! \{ + + //! Either references a \ref Section where the label is bound or \ref ExtraData. + SectionOrLabelEntryExtraHeader* _object_data; + + //! Label entry payload. + //! + //! When a Label is bound, `_offset_or_fixups` is the relative offset from the start of the section where + //! the \ref Label has been bound, otherwise `_offset_or_fixups` is a pointer to the first \ref Fixup. + uint64_t _offset_or_fixups; + + //! \} + + //! \name Accessors + //! \{ + + //! Returns the type of the label. + //! + //! The type of the label depends on how it was created. Most JIT code uses unnamed anonymous labels created by + //! emitters, for example \ref BaseEmitter::new_label() returns a \ref Label instance having id that was created + //! by \ref CodeHolder::new_label_id. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG LabelType label_type() const noexcept { return _object_data->_internal_label_type; } + + //! Returns label flags. + //! + //! \note Label flags are mostly for internal use, there is probably no reason to use them in user code. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG LabelFlags label_flags() const noexcept { return _object_data->_internal_label_flags; } + + //! Tests whether the label has the given `flag` set. + //! + //! \note Using other getters instead is advised, for example using \ref has_name() and \ref has_parent() is better + //! (and shorter) than checking label flags. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_label_flag(LabelFlags flag) const noexcept { return Support::test(_object_data->_internal_label_flags, flag); } + + //! Tests whether the LabelEntry has own extra data (see \ref LabelEntry::ExtraData). + //! + //! \note This should only be used by AsmJit for internal purposes. Own extra data means that the LabelEntry has + //! a mutable extra data separately allocated. This information should not be necessary to users as LabelEntry + //! getters should encapsulate label introspection. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool _has_own_extra_data() const noexcept { return has_label_flag(LabelFlags::kHasOwnExtraData); } + + //! Tests whether the Label represented by this LabelEntry has a name. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_name() const noexcept { return has_label_flag(LabelFlags::kHasName); } + + //! Tests whether the Label represented by this LabelEntry has a parent label. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_parent() const noexcept { return has_label_flag(LabelFlags::kHasParent); } + + //! Tests whether the label represented by this LabelEntry is bound. + //! + //! Bound label means that it has an associated \ref Section and a position in such section. Labels are bound by + //! calling \ref BaseEmitter::bind() method with \ref Label operand. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_bound() const noexcept { return _object_data->_section_id != Globals::kInvalidId; } + + //! Tests whether the label is bound to a the given `section`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_bound_to(const Section* section) const noexcept { return _object_data->_section_id == section->section_id(); } + + //! Tests whether the label is bound to a the given `section_id`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_bound_to(uint32_t section_id) const noexcept { return _object_data->_section_id == section_id; } + + //! Returns the section where the label was bound. + //! + //! If the label was not yet bound the return value is `nullptr`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t section_id() const noexcept { return _object_data->_section_id; } + + [[nodiscard]] + ASMJIT_INLINE ExtraData* _own_extra_data() const noexcept { + ASMJIT_ASSERT(_has_own_extra_data()); + return static_cast<ExtraData*>(_object_data); + } + + //! Returns label's parent id or \ref Globals::kInvalidId if the label has no parent. + [[nodiscard]] + ASMJIT_INLINE uint32_t parent_id() const noexcept { + return _has_own_extra_data() ? _own_extra_data()->_parent_id : Globals::kInvalidId; + } + + //! Returns the label's name. + //! + //! \note Local labels will return their local name without their parent part, for example ".L1". + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const char* name() const noexcept { + return has_name() ? _own_extra_data()->name() : nullptr; + } + + //! Returns size of label's name. + //! + //! \note Label name is always null terminated, so you can use `strlen()` to get it, however, it's also cached in + //! `LabelEntry` itself, so if you want to know the size the fastest way is to call `LabelEntry::name_size()`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint32_t name_size() const noexcept { + return has_name() ? _own_extra_data()->_name_size : uint32_t(0); + } + + //! Returns unresolved fixups associated with this label. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_fixups() const noexcept { + return Support::bool_and(!is_bound(), _offset_or_fixups != 0u); + } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Fixup* _get_fixups() const noexcept { return reinterpret_cast<Fixup*>(uintptr_t(_offset_or_fixups)); } + + ASMJIT_INLINE_NODEBUG void _set_fixups(Fixup* first) noexcept { _offset_or_fixups = reinterpret_cast<uintptr_t>(first); } + + //! Returns unresolved fixups associated with this label. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Fixup* unresolved_fixups() const noexcept { return !is_bound() ? _get_fixups() : nullptr; } + + //! Returns the label offset (can only be used after the label is bound). + //! + //! \note This would trigger an assertion failure in debug builds when called on an unbound label. When accessing + //! offsets, always check whether the label is bound. Unbound labels don't have offsets. + [[nodiscard]] + ASMJIT_INLINE uint64_t offset() const noexcept { + ASMJIT_ASSERT(is_bound()); + return _offset_or_fixups; + } + + //! \} +}; + +//! Holds assembled code and data (including sections, labels, and relocation information). +//! +//! CodeHolder connects emitters with their targets. It provides them interface that can be used to query information +//! about the target environment (architecture, etc...) and API to create labels, sections, relocations, and to write +//! data to a \ref CodeBuffer, which is always part of \ref Section. More than one emitter can be attached to a single +//! CodeHolder instance at a time, which is used in practice +//! +//! CodeHolder provides interface for all emitter types. Assemblers use CodeHolder to write into \ref CodeBuffer, and +//! higher level emitters like Builder and Compiler use CodeHolder to manage labels and sections so higher level code +//! can be serialized to Assembler by \ref BaseEmitter::finalize() and \ref BaseBuilder::serialize_to(). +//! +//! In order to use CodeHolder, it must be first initialized by \ref init(). After the CodeHolder has been successfully +//! initialized it can be used to hold assembled code, sections, labels, relocations, and to attach / detach code +//! emitters. After the end of code generation it can be used to query physical locations of labels and to relocate +//! the assembled code into the right address. Please not that calling \ref init() twice doesn't work and would return +//! an error - to reuse CodeHolder it has to be first \ref reset() or reinitialized by calling \ref reinit(). +//! +//! Multiple Functions +//! ------------------ +//! +//! CodeHolder can be used to hold a single function or multiple functions - when it's holding multiple functions it's +//! considered like a module (or library, or something that provides more than just a single function). When a code is +//! relocated and moved into executable memory, you typically get a single pointer back. When CodeHolder holds a single +//! function, it's the pointer to such function. However, when CodeHolder holds multiple functions, that pointer is +//! basically start of the code, which is usually the first function. +//! +//! In order to get a pointer to more functions, it's necessary to use \ref Label for each function and then to get the +//! offset to each such function via \ref CodeHolder::label_offset_from_base() - which returns an offset, which is relative +//! to the start of the assembled code. When using higher level emitters such as \ref asmjit_compiler labels are created +//! automatically - \ref FuncNode inherits from \ref LabelNode, so a function is a label at the same time. +//! +//! To query and apply an offset, consider the following code, which uses \ref x86::Compiler to create two functions: +//! +//! ``` +//! #include <asmjit/x86.h> +//! #include <stdio.h> +//! #include <string.h> +//! +//! int main(int argc, char* argv[]) { +//! using namespace asmjit; +//! +//! JitRuntime rt; +//! CodeHolder code; +//! code.init(rt.environment()); +//! +//! x86::Compiler cc(&code); +//! +//! // Generate first function. +//! FuncNode* func1_node = cc.add_func(FuncSignature::build<uint32_t>()); +//! Label func1_label = func1_node->label(); +//! +//! { +//! x86::Gp r = cc.new_gp32("r0"); +//! cc.mov(r, 0); +//! cc.ret(r); +//! cc.end_func(); +//! } +//! +//! // Generate second function. +//! FuncNode* func2_node = cc.add_func(FuncSignature::build<uint32_t>()); +//! Label func2_label = func2_node->label(); +//! +//! { +//! x86::Gp r = cc.new_gp32("r1"); +//! cc.mov(r, 1); +//! cc.ret(r); +//! cc.end_func(); +//! } +//! +//! // Finalize the generated code - this would also call `serialize_to()`. +//! Error err = cc.finalize(); +//! if (err != Error::kOk) { +//! printf("ERROR during finalization: %s\n", DebugUtils::error_as_string(err)); +//! return 1; +//! } +//! +//! // We have deliberately used void* as a pointer type as it's start of an assembled module. +//! void* module; +//! err = rt.add(&module, &code); +//! +//! if (err != Error::kOk) { +//! printf("ERROR during allocation/relocation: %s\n", DebugUtils::error_as_string(err)); +//! return 1; +//! } +//! +//! // Normally both CodeHolder and Compiler are not needed after the code has been finalized +//! // and allocated/relocated into an executable memory. However, in order to get the required +//! // offsets it's necessary to query CodeHolder for positions in code, and to get these it's +//! // required to either have `FuncNode` or `Label`. +//! size_t func1_offset = code.label_offset_from_base(func1_label); +//! size_t func2_offset = code.label_offset_from_base(func2_label); +//! +//! using Fn = uint32_t(*)(void); +//! +//! Fn fn1 = ptr_as_func<Fn>(module, func1_offset); +//! Fn fn2 = ptr_as_func<Fn>(module, func2_offset); +//! +//! printf("fn1()=%u fn2()=%u\n", fn1(), fn2()); +//! +//! // The module has to be released at once - individual functions cannot be released. +//! rt.release(module); +//! +//! return 0; +//! } +//! ``` +//! +//! CodeHolder Reusability +//! ---------------------- +//! +//! If you intend to generate a lot of code, or tiny code, it's advised to reuse CodeHolder and emitter instances. +//! There are currently two ways of reusing CodeHolder and emitters - one is using \ref CodeHolder::init() followed +//! by \ref CodeHolder::reset(), and another is initializing once by \ref CodeHolder::init() and then reinitializing +//! by \ref CodeHolder::reinit(). The first strategy is shown below: +//! +//! ``` +//! // All of them will be reused for code generation by using an 'init()/reset()' strategy. +//! Environment env = ...; // Environment to use, for example from JitRuntime. +//! CodeHolder code; // CodeHolder to reuse (all allocated memory will be held by it until it's destroyed). +//! x86::Compiler cc; // Emitter to reuse (for example x86::Compiler). +//! +//! for (size_t i = 0; i < ...; i++) { +//! // Initialize the CodeHolder first. +//! code.init(env); +//! code.attach(&emitter); +//! +//! [[code generation as usual]] +//! +//! code.reset(); +//! } +//! ``` +//! +//! While this approach is good for many use-cases, there is even a faster strategy called reinitialization, which is +//! provided by \ref CodeHolder::reinit(). The idea of reinit is to reinitialize the CodeHolder into a state, which +//! was achieved by initializing it by \ref CodeHolder::init(), by optionally attaching \ref Logger, \ref ErrorHandler, +//! and emitters of any kind. See an example below: +//! +//! ``` +//! // All of them will be reused for code generation by using a 'reinit()' strategy. +//! Environment env = ...; // Environment to use, for example from JitRuntime. +//! CodeHolder code; // CodeHolder to reuse (all allocated memory will be held by it until it's destroyed). +//! x86::Compiler cc; // Emitter to reuse (for example x86::Compiler). +//! +//! // Initialize the CodeHolder and attach emitters to it (attaching ErrorHandler is advised!) +//! code.init(env); +//! code.attach(&emitter); +//! +//! for (size_t i = 0; i < ...; i++) { +//! [[code generation as usual]] +//! +//! // Optionally you can start the loop with 'code.reinit()', but this is cleaner as it wipes out all intermediate +//! // states of CodeHolder and the attached emitters. It won't detach Logger, ErrorHandler, nor attached emitters. +//! code.reinit(); +//! } +//! ``` +//! +//! \note \ref CodeHolder has an ability to attach an \ref ErrorHandler, however, the error handler is not triggered +//! by \ref CodeHolder itself, it's instead propagated to all emitters that attach to it. +class CodeHolder { +public: + ASMJIT_NONCOPYABLE(CodeHolder) + + //! \name Types + //! \{ + + //! \cond INTERNAL + struct NamedLabelExtraData : public ArenaHashNode { + LabelEntry::ExtraData extra_data; + + ASMJIT_INLINE_NODEBUG uint32_t label_id() const noexcept { return _custom_data; } + }; + //! \endcond + + //! An informative data structure that is filled with some details that happened during \ref relocate_to_base(). + struct RelocationSummary { + //! The number of bytes the final code has been reduced by. + //! + //! At the moment this is the same as the number of bytes that the address table was shrunk, because it was + //! possible to avoid certain entries during relocation - the functions that would be otherwise present were + //! close enough to avoid them in the .addrtab section. + size_t code_size_reduction; + }; + + //! \} + + //! \name Members + //! \{ + + //! Environment information. + Environment _environment; + //! CPU features of the target architecture. + CpuFeatures _cpu_features; + //! Base address or \ref Globals::kNoBaseAddress. + uint64_t _base_address; + + //! Attached `Logger`, used by all consumers. + Logger* _logger; + //! Attached `ErrorHandler`. + ErrorHandler* _error_handler; + + //! Arena allocator used to allocate core structures. + Arena _arena; + + //! First emitter attached to this CodeHolder (double-linked list). + BaseEmitter* _attached_first; + //! Last emitter attached to this CodeHolder (double-linked list). + BaseEmitter* _attached_last; + + //! Section entries. + ArenaVector<Section*> _sections; + //! Section entries sorted by section order and then section id. + ArenaVector<Section*> _sections_by_order; + + //! Label entries. + ArenaVector<LabelEntry> _label_entries; + //! Relocation entries. + ArenaVector<RelocEntry*> _relocations; + //! Label name -> LabelEntry::ExtraData (only used by labels that have a name and are not anonymous). + ArenaHash<NamedLabelExtraData> _named_labels; + //! Unresolved fixups that are most likely references across sections. + Fixup* _fixups; + //! Pool containing \ref Fixup instances for quickly recycling them. + ArenaPool<Fixup> _fixup_data_pool; + //! Count of unresolved fixups of unbound labels (at the end of assembling this should be zero). + size_t _unresolved_fixup_count; + + //! Text section - always one part of a CodeHolder itself. + Section _text_section; + + //! Pointer to an address table section (or null if this section doesn't exist). + Section* _address_table_section; + //! Address table entries. + ArenaTree<AddressTableEntry> _address_table_entries; + + //! \} + + //! \name Construction & Destruction + //! \{ + + //! Creates an uninitialized CodeHolder (you must init() it before it can be used). + //! + //! An optional `temporary` argument can be used to initialize the first block of \ref Arena + //! that \ref CodeHolder uses into a temporary memory provided by the user. + ASMJIT_API explicit CodeHolder(Span<uint8_t> static_arena_memory = Span<uint8_t>{}) noexcept; + + //! Destroys the CodeHolder and frees all resources it has allocated. + ASMJIT_API ~CodeHolder() noexcept; + + //! Tests whether the `CodeHolder` has been initialized. + //! + //! Emitters can be only attached to initialized `CodeHolder` instances. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_initialized() const noexcept { return _environment.is_initialized(); } + + //! Initializes CodeHolder to hold code described by the given `environment` and `base_address`. + ASMJIT_API Error init(const Environment& environment, uint64_t base_address = Globals::kNoBaseAddress) noexcept; + //! Initializes CodeHolder to hold code described by the given `environment`, `cpu_features`, and `base_address`. + ASMJIT_API Error init(const Environment& environment, const CpuFeatures& cpu_features, uint64_t base_address = Globals::kNoBaseAddress) noexcept; + + //! Reinitializes CodeHolder with the same environment, cpu features, and base address as it had, and notifies + //! all attached emitters of reinitialization. If the \ref CodeHolder was not initialized, \ref Error::kNotInitialized + //! is returned. + //! + //! Reinitialization is designed to be a faster alternative compared to \ref reset() followed by \ref init() chain. + //! The purpose of reinitialization is a very quick reuse of \ref CodeHolder and all attached emitters (most likely + //! Assembler or Compiler) without paying the cost of complete initialization and then assignment of all the loggers, + //! error handlers, and emitters. + //! + //! \note Semantically reinit() is the same as using \ref reset() with \ref ResetPolicy::kSoft parameter followed by + //! \ref init(), and then by attaching loggers, error handlers, and emitters that were attached previously. This + //! means that after reinitialization you will get a clean and ready for use \ref CodeHolder, which was initialized + //! the same way as before. + ASMJIT_API Error reinit() noexcept; + + //! Detaches all code-generators attached and resets the `CodeHolder`. + ASMJIT_API void reset(ResetPolicy reset_policy = ResetPolicy::kSoft) noexcept; + + //! \} + + //! \name Attach & Detach + //! \{ + + //! Attaches an emitter to this `CodeHolder`. + ASMJIT_API Error attach(BaseEmitter* emitter) noexcept; + //! Detaches an emitter from this `CodeHolder`. + ASMJIT_API Error detach(BaseEmitter* emitter) noexcept; + + //! \} + + //! \name Memory Allocators + //! \{ + + //! Returns the allocator that the `CodeHolder` uses. + //! + //! \note This should be only used for AsmJit's purposes. Code holder uses arena allocator to allocate everything, + //! so anything allocated through this allocator will be invalidated by \ref CodeHolder::reset() or by CodeHolder's + //! destructor. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Arena& arena() const noexcept { return const_cast<Arena&>(_arena); } + + //! \} + + //! \name Code & Architecture + //! \{ + + //! Returns the target environment information. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const Environment& environment() const noexcept { return _environment; } + + //! Returns the target architecture. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Arch arch() const noexcept { return environment().arch(); } + + //! Returns the target sub-architecture. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG SubArch sub_arch() const noexcept { return environment().sub_arch(); } + + //! Returns the minimum CPU features of the target architecture. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const CpuFeatures& cpu_features() const noexcept { return _cpu_features; } + + //! Tests whether a static base-address is set. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_base_address() const noexcept { return _base_address != Globals::kNoBaseAddress; } + + //! Returns a static base-address or \ref Globals::kNoBaseAddress, if not set. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t base_address() const noexcept { return _base_address; } + + //! \} + + //! \name Attached Emitters + //! \{ + + //! Returns a vector of attached emitters. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG BaseEmitter* attached_first() noexcept { return _attached_first; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG BaseEmitter* attached_last() noexcept { return _attached_last; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const BaseEmitter* attached_first() const noexcept { return _attached_first; } + + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const BaseEmitter* attached_last() const noexcept { return _attached_last; } + + //! \} + + //! \name Logging + //! \{ + + //! Returns the attached logger. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Logger* logger() const noexcept { return _logger; } + + //! Attaches a `logger` to CodeHolder and propagates it to all attached emitters. + ASMJIT_API void set_logger(Logger* logger) noexcept; + + //! Resets the logger to none. + ASMJIT_INLINE_NODEBUG void reset_logger() noexcept { set_logger(nullptr); } + + //! \name Error Handling + //! \{ + + //! Tests whether the CodeHolder has an attached error handler, see \ref ErrorHandler. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_error_handler() const noexcept { return _error_handler != nullptr; } + + //! Returns the attached error handler. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG ErrorHandler* error_handler() const noexcept { return _error_handler; } + + //! Attach an error handler to this `CodeHolder`. + ASMJIT_API void set_error_handler(ErrorHandler* error_handler) noexcept; + + //! Resets the error handler to none. + ASMJIT_INLINE_NODEBUG void reset_error_handler() noexcept { set_error_handler(nullptr); } + + //! \} + + //! \name Code Buffer + //! \{ + + //! Makes sure that at least `n` bytes can be added to CodeHolder's buffer `cb`. + //! + //! \note The buffer `cb` must be managed by `CodeHolder` - otherwise the behavior of the function is undefined. + ASMJIT_API Error grow_buffer(CodeBuffer* cb, size_t n) noexcept; + + //! Reserves the size of `cb` to at least `n` bytes. + //! + //! \note The buffer `cb` must be managed by `CodeHolder` - otherwise the behavior of the function is undefined. + ASMJIT_API Error reserve_buffer(CodeBuffer* cb, size_t n) noexcept; + + //! \} + + //! \name Sections + //! \{ + + //! Returns an array of `Section*` records. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Span<Section*> sections() const noexcept { return _sections.as_span(); } + + //! Returns an array of `Section*` records sorted according to section order first, then section id. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Span<Section*> sections_by_order() const noexcept { return _sections_by_order.as_span(); } + + //! Returns the number of sections. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG size_t section_count() const noexcept { return _sections.size(); } + + //! Tests whether the given `section_id` is valid. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_section_valid(uint32_t section_id) const noexcept { return section_id < _sections.size(); } + + //! Creates a new section and return its pointer in `section_out`. + //! + //! Returns `Error`, does not report a possible error to `ErrorHandler`. + ASMJIT_API Error new_section(Out<Section*> section_out, const char* name, size_t name_size = SIZE_MAX, SectionFlags flags = SectionFlags::kNone, uint32_t alignment = 1, int32_t order = 0) noexcept; + + //! Returns a section entry of the given index. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Section* section_by_id(uint32_t section_id) const noexcept { return _sections[section_id]; } + + //! Returns section-id that matches the given `name`. + //! + //! If there is no such section `Section::kInvalidId` is returned. + [[nodiscard]] + ASMJIT_API Section* section_by_name(const char* name, size_t name_size = SIZE_MAX) const noexcept; + + //! Returns '.text' section (section that commonly represents code). + //! + //! \note Text section is always the first section in \ref CodeHolder::sections() array. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Section* text_section() const noexcept { return _sections[0]; } + + //! Tests whether '.addrtab' section exists. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_address_table_section() const noexcept { return _address_table_section != nullptr; } + + //! Returns '.addrtab' section. + //! + //! This section is used exclusively by AsmJit to store absolute 64-bit + //! addresses that cannot be encoded in instructions like 'jmp' or 'call'. + //! + //! \note This section is created on demand, the returned pointer can be null. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Section* address_table_section() const noexcept { return _address_table_section; } + + //! Ensures that '.addrtab' section exists (creates it if it doesn't) and + //! returns it. Can return `nullptr` on out of memory condition. + [[nodiscard]] + ASMJIT_API Section* ensure_address_table_section() noexcept; + + //! Used to add an address to an address table. + //! + //! This implicitly calls `ensure_address_table_section()` and then creates `AddressTableEntry` that is inserted + //! to `_address_table_entries`. If the address already exists this operation does nothing as the same addresses + //! use the same slot. + //! + //! This function should be considered internal as it's used by assemblers to insert an absolute address into the + //! address table. Inserting address into address table without creating a particular relocation entry makes no sense. + ASMJIT_API Error add_address_to_address_table(uint64_t address) noexcept; + + //! \} + + //! \name Labels & Symbols + //! \{ + + //! Returns array of `LabelEntry` records. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Span<LabelEntry> label_entries() const noexcept { return _label_entries.as_span(); } + + //! Returns number of labels created. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG size_t label_count() const noexcept { return _label_entries.size(); } + + //! Tests whether the label having `label_id` is valid (i.e. created by `new_label_id()`). + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_label_valid(uint32_t label_id) const noexcept { + return label_id < _label_entries.size(); + } + + //! Tests whether the `label` is valid (i.e. created by `new_label_id()`). + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_label_valid(const Label& label) const noexcept { + return is_label_valid(label.id()); + } + + //! Tests whether a label having `label_id` is already bound. + //! + //! Returns `false` if the `label_id` is not valid. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_label_bound(uint32_t label_id) const noexcept { + return is_label_valid(label_id) && _label_entries[label_id].is_bound(); + } + + //! Tests whether the `label` is already bound. + //! + //! Returns `false` if the `label` is not valid. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool is_label_bound(const Label& label) const noexcept { + return is_label_bound(label.id()); + } + + //! Returns LabelEntry of the given label identifier `label_id` (or `label` if you are using overloads). + //! + //! \attention The passed `label_id` must be valid as it's used as an index to `_label_entries[]` array. In debug + //! builds the array access uses an assertion, but such assertion is not present in release builds. To get whether + //! a label is valid, check out \ref CodeHolder::is_label_valid() function. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG LabelEntry& label_entry_of(uint32_t label_id) noexcept { + return _label_entries[label_id]; + } + + //! \overload + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const LabelEntry& label_entry_of(uint32_t label_id) const noexcept { + return _label_entries[label_id]; + } + + //! \overload + [[nodiscard]] + ASMJIT_INLINE_NODEBUG LabelEntry& label_entry_of(const Label& label) noexcept { + return label_entry_of(label.id()); + } + + //! \overload + [[nodiscard]] + ASMJIT_INLINE_NODEBUG const LabelEntry& label_entry_of(const Label& label) const noexcept { + return label_entry_of(label.id()); + } + + //! Returns offset of a `Label` by its `label_id`. + //! + //! The offset returned is relative to the start of the section where the label is bound. Zero offset is returned + //! for unbound labels, which is their initial offset value. + //! + //! \attention The passed `label_id` must be valid as it's used as an index to `_label_entries[]` array. In debug + //! builds the array access uses an assertion, but such assertion is not present in release builds. To get whether + //! a label is valid, check out \ref CodeHolder::is_label_valid() function. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t label_offset(uint32_t label_id) const noexcept { + ASMJIT_ASSERT(is_label_valid(label_id)); + return _label_entries[label_id].offset(); + } + + //! \overload + [[nodiscard]] + ASMJIT_INLINE_NODEBUG uint64_t label_offset(const Label& label) const noexcept { + return label_offset(label.id()); + } + + //! Returns offset of a label by it's `label_id` relative to the base offset. + //! + //! \attention The passed `label_id` must be valid as it's used as an index to `_label_entries[]` array. In debug + //! builds the array access uses an assertion, but such assertion is not present in release builds. To get whether + //! a label is valid, check out \ref CodeHolder::is_label_valid() function. + //! + //! \note The offset of the section where the label is bound must be valid in order to use this function, otherwise + //! the value returned will not be reliable. Typically, sections have offsets when they are flattened, see \ref + //! CodeHolder::flatten() function for more details. + [[nodiscard]] + inline uint64_t label_offset_from_base(uint32_t label_id) const noexcept { + ASMJIT_ASSERT(is_label_valid(label_id)); + + const LabelEntry& le = _label_entries[label_id]; + return (le.is_bound() ? _sections[le.section_id()]->offset() : uint64_t(0)) + le.offset(); + } + + //! \overload + [[nodiscard]] + inline uint64_t label_offset_from_base(const Label& label) const noexcept { + return label_offset_from_base(label.id()); + } + + //! Creates a new anonymous label and return its id in `label_id_out`. + //! + //! Returns `Error`, does not report error to `ErrorHandler`. + [[nodiscard]] + ASMJIT_API Error new_label_id(Out<uint32_t> label_id_out) noexcept; + + //! Creates a new named \ref LabelEntry of the given label `type`. + //! + //! \param label_id_out Where to store the created \ref Label id. + //! \param name The name of the label. + //! \param name_size The length of `name` argument, or `SIZE_MAX` if `name` is a null terminated string, which + //! means that the `CodeHolder` will use `strlen()` to determine the length. + //! \param type The type of the label to create, see \ref LabelType. + //! \param parent_id Parent id of a local label, otherwise it must be \ref Globals::kInvalidId. + //! \retval Always returns \ref Error, does not report a possible error to the attached \ref ErrorHandler. + //! + //! AsmJit has a support for local labels (\ref LabelType::kLocal) which require a parent label id (parent_id). + //! The names of local labels can conflict with names of other local labels that have a different parent. In + //! addition, AsmJit supports named anonymous labels, which are useful only for debugging purposes as the + //! anonymous name will have a name, which will be formatted, but the label itself cannot be queried by such + //! name. + [[nodiscard]] + ASMJIT_API Error new_named_label_id(Out<uint32_t> label_id_out, const char* name, size_t name_size, LabelType type, uint32_t parent_id = Globals::kInvalidId) noexcept; + + //! Returns a label by name. + //! + //! \remarks If the named label doesn't exist a default constructed \ref Label is returned, which has its id set + //! to \ref Globals::kInvalidId. In other words, this function doesn't create new labels, it can only be used to + //! query an existing \ref Label by name. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Label label_by_name(const char* name, size_t name_size = SIZE_MAX, uint32_t parent_id = Globals::kInvalidId) noexcept { + return Label(label_id_by_name(name, name_size, parent_id)); + } + + //! \overload + [[nodiscard]] + ASMJIT_API Label label_by_name(Span<const char> name, uint32_t parent_id = Globals::kInvalidId) noexcept { + return label_by_name(name.data(), name.size(), parent_id); + } + + //! Returns a label id by name. + //! + //! \remarks If the named label doesn't exist \ref Globals::kInvalidId is returned. In other words, this function + //! doesn't create new labels, it can only be used to query an existing label identifier by name. + [[nodiscard]] + ASMJIT_API uint32_t label_id_by_name(const char* name, size_t name_size = SIZE_MAX, uint32_t parent_id = Globals::kInvalidId) noexcept; + + //! \overload + [[nodiscard]] + ASMJIT_API uint32_t label_id_by_name(Span<const char> name, uint32_t parent_id = Globals::kInvalidId) noexcept { + return label_id_by_name(name.data(), name.size(), parent_id); + } + + //! Tests whether there are any unresolved fixups related to unbound labels. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_unresolved_fixups() const noexcept { return _unresolved_fixup_count != 0u; } + + //! Returns the number of unresolved fixups. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG size_t unresolved_fixup_count() const noexcept { return _unresolved_fixup_count; } + + //! Creates a new label-link used to store information about yet unbound labels. + //! + //! Returns `null` if the allocation failed. + [[nodiscard]] + ASMJIT_API Fixup* new_fixup(LabelEntry& le, uint32_t section_id, size_t offset, intptr_t rel, const OffsetFormat& format) noexcept; + + //! Resolves cross-section fixups associated with each label that was used as a destination in code of a different + //! section. It's only useful to people that use multiple sections as it will do nothing if the code only contains + //! a single section in which cross-section fixups are not possible. + ASMJIT_API Error resolve_cross_section_fixups() noexcept; + + //! Binds a label to a given `section_id` and `offset` (relative to start of the section). + //! + //! This function is generally used by `BaseAssembler::bind()` to do the heavy lifting. + ASMJIT_API Error bind_label(const Label& label, uint32_t section_id, uint64_t offset) noexcept; + + //! \} + + //! \name Relocations + //! \{ + + //! Tests whether the code contains relocation entries. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG bool has_reloc_entries() const noexcept { return !_relocations.is_empty(); } + + //! Returns array of `RelocEntry*` records. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG Span<RelocEntry*> reloc_entries() const noexcept { return _relocations.as_span(); } + + //! Returns a RelocEntry of the given `id`. + [[nodiscard]] + ASMJIT_INLINE_NODEBUG RelocEntry* reloc_entry_of(uint32_t id) const noexcept { return _relocations[id]; } + + //! Creates a new relocation entry of type `reloc_type`. + //! + //! Additional fields can be set after the relocation entry was created. + [[nodiscard]] + ASMJIT_API Error new_reloc_entry(Out<RelocEntry*> dst, RelocType reloc_type) noexcept; + + //! \} + + //! \name Utilities + //! \{ + + //! Flattens all sections by recalculating their offsets, starting at 0. + //! + //! \note This should never be called more than once. + ASMJIT_API Error flatten() noexcept; + + //! Returns computed the size of code & data of all sections. + //! + //! \note All sections will be iterated over and the code size returned would represent the minimum code size of + //! all combined sections after applying minimum alignment. Code size may decrease after calling `flatten()` and + //! `relocate_to_base()`. + [[nodiscard]] + ASMJIT_API size_t code_size() const noexcept; + + //! Relocates the code to the given `base_address`. + //! + //! \param base_address Absolute base address where the code will be relocated to. Please note that nothing is + //! copied to such base address, it's just an absolute value used by the relocation code to resolve all stored + //! relocations. + //! + //! \param summary_out Optional argument that can be used to get back information about the relocation. + //! + //! \note This should never be called more than once. + ASMJIT_API Error relocate_to_base(uint64_t base_address, RelocationSummary* summary_out = nullptr) noexcept; + + //! Copies a single section into `dst`. + ASMJIT_API Error copy_section_data(void* dst, size_t dst_size, uint32_t section_id, CopySectionFlags copy_flags = CopySectionFlags::kNone) noexcept; + + //! Copies all sections into `dst`. + //! + //! This should only be used if the data was flattened and there are no gaps between the sections. The `dst_size` + //! is always checked and the copy will never write anything outside the provided buffer. + ASMJIT_API Error copy_flattened_data(void* dst, size_t dst_size, CopySectionFlags copy_flags = CopySectionFlags::kNone) noexcept; + + //! \} +}; + +//! \} + +ASMJIT_END_NAMESPACE + +#endif // ASMJIT_CORE_CODEHOLDER_H_INCLUDED |
