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+// This file is part of AsmJit project <https://asmjit.com>
+//
+// See asmjit.h or LICENSE.md for license and copyright information
+// SPDX-License-Identifier: Zlib
+
+#ifndef ASMJIT_X86_X86ASSEMBLER_H_INCLUDED
+#define ASMJIT_X86_X86ASSEMBLER_H_INCLUDED
+
+#include "../core/assembler.h"
+#include "../x86/x86emitter.h"
+#include "../x86/x86operand.h"
+
+ASMJIT_BEGIN_SUB_NAMESPACE(x86)
+
+//! \addtogroup asmjit_x86
+//! \{
+
+//! X86/X64 assembler implementation.
+//!
+//! x86::Assembler is a code emitter that emits machine code directly into the \ref CodeBuffer. The assembler is capable
+//! of targeting both 32-bit and 64-bit instruction sets, the instruction set can be configured through \ref CodeHolder.
+//!
+//! ### Basics
+//!
+//! The following example shows a basic use of `x86::Assembler`, how to generate a function that works in both 32-bit
+//! and 64-bit modes, and how to connect \ref JitRuntime, \ref CodeHolder, and `x86::Assembler`.
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! #include <stdio.h>
+//!
+//! using namespace asmjit;
+//!
+//! // Signature of the generated function.
+//! typedef int (*SumFunc)(const int* arr, size_t count);
+//!
+//! int main() {
+//! JitRuntime rt; // Create a runtime specialized for JIT.
+//! CodeHolder code; // Create a CodeHolder.
+//!
+//! code.init(rt.environment()); // Initialize code to match the JIT environment.
+//! x86::Assembler a(&code); // Create and attach x86::Assembler to code.
+//!
+//! // Decide between 32-bit CDECL, WIN64, and SysV64 calling conventions:
+//! // 32-BIT - passed all arguments by stack.
+//! // WIN64 - passes first 4 arguments by RCX, RDX, R8, and R9.
+//! // UNIX64 - passes first 6 arguments by RDI, RSI, RCX, RDX, R8, and R9.
+//! x86::Gp arr, cnt;
+//! x86::Gp sum = x86::eax; // Use EAX as 'sum' as it's a return register.
+//!
+//! if (ASMJIT_ARCH_BITS == 64) {
+//! #if defined(_WIN32)
+//! arr = x86::rcx; // First argument (array ptr).
+//! cnt = x86::rdx; // Second argument (number of elements)
+//! #else
+//! arr = x86::rdi; // First argument (array ptr).
+//! cnt = x86::rsi; // Second argument (number of elements)
+//! #endif
+//! }
+//! else {
+//! arr = x86::edx; // Use EDX to hold the array pointer.
+//! cnt = x86::ecx; // Use ECX to hold the counter.
+//! // Fetch first and second arguments from [ESP + 4] and [ESP + 8].
+//! a.mov(arr, x86::ptr(x86::esp, 4));
+//! a.mov(cnt, x86::ptr(x86::esp, 8));
+//! }
+//!
+//! Label Loop = a.newLabel(); // To construct the loop, we need some labels.
+//! Label Exit = a.newLabel();
+//!
+//! a.xor_(sum, sum); // Clear 'sum' register (shorter than 'mov').
+//! a.test(cnt, cnt); // Border case:
+//! a.jz(Exit); // If 'cnt' is zero jump to 'Exit' now.
+//!
+//! a.bind(Loop); // Start of a loop iteration.
+//! a.add(sum, x86::dword_ptr(arr)); // Add int at [arr] to 'sum'.
+//! a.add(arr, 4); // Increment 'arr' pointer.
+//! a.dec(cnt); // Decrease 'cnt'.
+//! a.jnz(Loop); // If not zero jump to 'Loop'.
+//!
+//! a.bind(Exit); // Exit to handle the border case.
+//! a.ret(); // Return from function ('sum' == 'eax').
+//! // ----> x86::Assembler is no longer needed from here and can be destroyed <----
+//!
+//! SumFunc fn;
+//! Error err = rt.add(&fn, &code); // Add the generated code to the runtime.
+//!
+//! if (err) return 1; // Handle a possible error returned by AsmJit.
+//! // ----> CodeHolder is no longer needed from here and can be destroyed <----
+//!
+//! static const int array[6] = { 4, 8, 15, 16, 23, 42 };
+//!
+//! int result = fn(array, 6); // Execute the generated code.
+//! printf("%d\n", result); // Print sum of array (108).
+//!
+//! rt.release(fn); // Explicitly remove the function from the runtime
+//! return 0; // Everything successful...
+//! }
+//! ```
+//!
+//! The example should be self-explanatory. It shows how to work with labels, how to use operands, and how to emit
+//! instructions that can use different registers based on runtime selection. It implements 32-bit CDECL, WIN64,
+//! and SysV64 caling conventions and will work on most X86/X64 environments.
+//!
+//! Although functions prologs / epilogs can be implemented manually, AsmJit provides utilities that can be used
+//! to create function prologs and epilogs automatically, see \ref asmjit_function for more details.
+//!
+//! ### Instruction Validation
+//!
+//! Assembler prefers speed over strictness by default. The implementation checks the type of operands and fails
+//! if the signature of types is invalid, however, it does only basic checks regarding registers and their groups
+//! used in instructions. It's possible to pass operands that don't form any valid signature to the implementation
+//! and succeed. This is usually not a problem as Assembler provides typed API so operand types are normally checked
+//! by C++ compiler at compile time, however, Assembler is fully dynamic and its \ref emit() function can be called
+//! with any instruction id, options, and operands. Moreover, it's also possible to form instructions that will be
+//! accepted by the typed API, for example by calling `mov(x86::eax, x86::al)` - the C++ compiler won't see a problem
+//! as both EAX and AL are \ref Gp registers.
+//!
+//! To help with common mistakes AsmJit allows to activate instruction validation. This feature instruments
+//! the Assembler to call \ref InstAPI::validate() before it attempts to encode any instruction.
+//!
+//! The example below illustrates how validation can be turned on:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! #include <stdio.h>
+//!
+//! using namespace asmjit;
+//!
+//! int main(int argc, char* argv[]) {
+//! JitRuntime rt; // Create a runtime specialized for JIT.
+//! CodeHolder code; // Create a CodeHolder.
+//!
+//! code.init(rt.environment()); // Initialize code to match the JIT environment.
+//! x86::Assembler a(&code); // Create and attach x86::Assembler to code.
+//!
+//! // Enable strict validation.
+//! a.addDiagnosticOptions(DiagnosticOptions::kValidateAssembler);
+//!
+//! // Try to encode invalid or ill-formed instructions.
+//! Error err;
+//!
+//! // Invalid instruction.
+//! err = a.mov(x86::eax, x86::al);
+//! printf("Status: %s\n", DebugUtils::errorAsString(err));
+//!
+//! // Invalid instruction.
+//! err = a.emit(x86::Inst::kIdMovss, x86::eax, x86::xmm0);
+//! printf("Status: %s\n", DebugUtils::errorAsString(err));
+//!
+//! // Ambiguous operand size - the pointer requires size.
+//! err = a.inc(x86::ptr(x86::rax), 1);
+//! printf("Status: %s\n", DebugUtils::errorAsString(err));
+//!
+//! return 0;
+//! }
+//! ```
+//!
+//! ### Native Registers
+//!
+//! All emitters provide functions to construct machine-size registers depending on the target. This feature is
+//! for users that want to write code targeting both 32-bit and 64-bit architectures at the same time. In AsmJit
+//! terminology such registers have prefix `z`, so for example on X86 architecture the following native registers
+//! are provided:
+//!
+//! - `zax` - mapped to either `eax` or `rax`
+//! - `zbx` - mapped to either `ebx` or `rbx`
+//! - `zcx` - mapped to either `ecx` or `rcx`
+//! - `zdx` - mapped to either `edx` or `rdx`
+//! - `zsp` - mapped to either `esp` or `rsp`
+//! - `zbp` - mapped to either `ebp` or `rbp`
+//! - `zsi` - mapped to either `esi` or `rsi`
+//! - `zdi` - mapped to either `edi` or `rdi`
+//!
+//! They are accessible through \ref x86::Assembler, \ref x86::Builder, and \ref x86::Compiler. The example below
+//! illustrates how to use this feature:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! #include <stdio.h>
+//!
+//! using namespace asmjit;
+//!
+//! typedef int (*Func)(void);
+//!
+//! int main(int argc, char* argv[]) {
+//! JitRuntime rt; // Create a runtime specialized for JIT.
+//! CodeHolder code; // Create a CodeHolder.
+//!
+//! code.init(rt.environment()); // Initialize code to match the JIT environment.
+//! x86::Assembler a(&code); // Create and attach x86::Assembler to code.
+//!
+//! // Let's get these registers from x86::Assembler.
+//! x86::Gp zbp = a.zbp();
+//! x86::Gp zsp = a.zsp();
+//!
+//! int stackSize = 32;
+//!
+//! // Function prolog.
+//! a.push(zbp);
+//! a.mov(zbp, zsp);
+//! a.sub(zsp, stackSize);
+//!
+//! // ... emit some code (this just sets return value to zero) ...
+//! a.xor_(x86::eax, x86::eax);
+//!
+//! // Function epilog and return.
+//! a.mov(zsp, zbp);
+//! a.pop(zbp);
+//! a.ret();
+//!
+//! // To make the example complete let's call it.
+//! Func fn;
+//! Error err = rt.add(&fn, &code); // Add the generated code to the runtime.
+//! if (err) return 1; // Handle a possible error returned by AsmJit.
+//!
+//! int result = fn(); // Execute the generated code.
+//! printf("%d\n", result); // Print the resulting "0".
+//!
+//! rt.release(fn); // Remove the function from the runtime.
+//! return 0;
+//! }
+//! ```
+//!
+//! The example just returns `0`, but the function generated contains a standard prolog and epilog sequence and the
+//! function itself reserves 32 bytes of local stack. The advantage is clear - a single code-base can handle multiple
+//! targets easily. If you want to create a register of native size dynamically by specifying its id it's also possible:
+//!
+//! ```
+//! void example(x86::Assembler& a) {
+//! x86::Gp zax = a.gpz(x86::Gp::kIdAx);
+//! x86::Gp zbx = a.gpz(x86::Gp::kIdBx);
+//! x86::Gp zcx = a.gpz(x86::Gp::kIdCx);
+//! x86::Gp zdx = a.gpz(x86::Gp::kIdDx);
+//!
+//! // You can also change register's id easily.
+//! x86::Gp zsp = zax;
+//! zsp.setId(4); // or x86::Gp::kIdSp.
+//! }
+//! ```
+//!
+//! ### Data Embedding
+//!
+//! x86::Assembler extends the standard \ref BaseAssembler with X86/X64 specific conventions that are often used by
+//! assemblers to embed data next to the code. The following functions can be used to embed data:
+//!
+//! - \ref BaseAssembler::embedInt8() - embeds int8_t (portable naming).
+//! - \ref BaseAssembler::embedUInt8() - embeds uint8_t (portable naming).
+//! - \ref BaseAssembler::embedInt16() - embeds int16_t (portable naming).
+//! - \ref BaseAssembler::embedUInt16() - embeds uint16_t (portable naming).
+//! - \ref BaseAssembler::embedInt32() - embeds int32_t (portable naming).
+//! - \ref BaseAssembler::embedUInt32() - embeds uint32_t (portable naming).
+//! - \ref BaseAssembler::embedInt64() - embeds int64_t (portable naming).
+//! - \ref BaseAssembler::embedUInt64() - embeds uint64_t (portable naming).
+//! - \ref BaseAssembler::embedFloat() - embeds float (portable naming).
+//! - \ref BaseAssembler::embedDouble() - embeds double (portable naming).
+//!
+//! - \ref x86::Assembler::db() - embeds byte (8 bits) (x86 naming).
+//! - \ref x86::Assembler::dw() - embeds word (16 bits) (x86 naming).
+//! - \ref x86::Assembler::dd() - embeds dword (32 bits) (x86 naming).
+//! - \ref x86::Assembler::dq() - embeds qword (64 bits) (x86 naming).
+//!
+//! The following example illustrates how embed works:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! using namespace asmjit;
+//!
+//! void embedData(x86::Assembler& a) {
+//! a.db(0xFF); // Embeds 0xFF byte.
+//! a.dw(0xFF00); // Embeds 0xFF00 word (little-endian).
+//! a.dd(0xFF000000); // Embeds 0xFF000000 dword (little-endian).
+//! a.embedFloat(0.4f); // Embeds 0.4f (32-bit float, little-endian).
+//! }
+//! ```
+//!
+//! Sometimes it's required to read the data that is embedded after code, for example. This can be done through
+//! \ref Label as shown below:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! using namespace asmjit;
+//!
+//! void embedData(x86::Assembler& a, const Label& L_Data) {
+//! x86::Gp addr = a.zax(); // EAX or RAX.
+//! x86::Gp val = x86::edi; // Where to store some value...
+//!
+//! // Approach 1 - Load the address to register through LEA. This approach
+//! // is flexible as the address can be then manipulated, for
+//! // example if you have a data array, which would need index.
+//! a.lea(addr, L_Data); // Loads the address of the label to EAX or RAX.
+//! a.mov(val, dword_ptr(addr));
+//!
+//! // Approach 2 - Load the data directly by using L_Data in address. It's
+//! // worth noting that this doesn't work with indexes in X64
+//! // mode. It will use absolute address in 32-bit mode and
+//! // relative address (RIP) in 64-bit mode.
+//! a.mov(val, dword_ptr(L_Data));
+//! }
+//! ```
+//!
+//! ### Label Embedding
+//!
+//! It's also possible to embed labels. In general AsmJit provides the following options:
+//!
+//! - \ref BaseEmitter::embedLabel() - Embeds absolute address of a label. This is target dependent and would
+//! embed either 32-bit or 64-bit data that embeds absolute label address. This kind of embedding cannot be
+//! used in a position independent code.
+//!
+//! - \ref BaseEmitter::embedLabelDelta() - Embeds a difference between two labels. The size of the difference
+//! can be specified so it's possible to embed 8-bit, 16-bit, 32-bit, and 64-bit difference, which is sufficient
+//! for most purposes.
+//!
+//! The following example demonstrates how to embed labels and their differences:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! using namespace asmjit;
+//!
+//! void embedLabel(x86::Assembler& a, const Label& L_Data) {
+//! // [1] Embed L_Data - the size of the data will be dependent on the target.
+//! a.embedLabel(L_Data);
+//!
+//! // [2] Embed a 32-bit difference of two labels.
+//! Label L_Here = a.newLabel();
+//! a.bind(L_Here);
+//! // Embeds int32_t(L_Data - L_Here).
+//! a.embedLabelDelta(L_Data, L_Here, 4);
+//! }
+//! ```
+//!
+//! ### Using FuncFrame and FuncDetail with x86::Assembler
+//!
+//! The example below demonstrates how \ref FuncFrame and \ref FuncDetail can be used together with \ref x86::Assembler
+//! to generate a function that will use platform dependent calling conventions automatically depending on the target:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! #include <stdio.h>
+//!
+//! using namespace asmjit;
+//!
+//! typedef void (*SumIntsFunc)(int* dst, const int* a, const int* b);
+//!
+//! int main(int argc, char* argv[]) {
+//! JitRuntime rt; // Create JIT Runtime.
+//! CodeHolder code; // Create a CodeHolder.
+//!
+//! code.init(rt.environment()); // Initialize code to match the JIT environment.
+//! x86::Assembler a(&code); // Create and attach x86::Assembler to code.
+//!
+//! // Decide which registers will be mapped to function arguments. Try changing
+//! // registers of dst, src_a, and src_b and see what happens in function's
+//! // prolog and epilog.
+//! x86::Gp dst = a.zax();
+//! x86::Gp src_a = a.zcx();
+//! x86::Gp src_b = a.zdx();
+//!
+//! X86::Xmm vec0 = x86::xmm0;
+//! X86::Xmm vec1 = x86::xmm1;
+//!
+//! // Create/initialize FuncDetail and FuncFrame.
+//! FuncDetail func;
+//! func.init(FuncSignatureT<void, int*, const int*, const int*>(CallConvId::kHost));
+//!
+//! FuncFrame frame;
+//! frame.init(func);
+//!
+//! // Make XMM0 and XMM1 dirty - RegGroup::kVec describes XMM|YMM|ZMM registers.
+//! frame.setDirtyRegs(RegGroup::kVec, IntUtils::mask(0, 1));
+//!
+//! // Alternatively, if you don't want to use register masks you can pass BaseReg
+//! // to addDirtyRegs(). The following code would add both xmm0 and xmm1.
+//! frame.addDirtyRegs(x86::xmm0, x86::xmm1);
+//!
+//! FuncArgsAssignment args(&func); // Create arguments assignment context.
+//! args.assignAll(dst, src_a, src_b);// Assign our registers to arguments.
+//! args.updateFrameInfo(frame); // Reflect our args in FuncFrame.
+//! frame.finalize(); // Finalize the FuncFrame (updates it).
+//!
+//! a.emitProlog(frame); // Emit function prolog.
+//! a.emitArgsAssignment(frame, args);// Assign arguments to registers.
+//! a.movdqu(vec0, x86::ptr(src_a)); // Load 4 ints from [src_a] to XMM0.
+//! a.movdqu(vec1, x86::ptr(src_b)); // Load 4 ints from [src_b] to XMM1.
+//! a.paddd(vec0, vec1); // Add 4 ints in XMM1 to XMM0.
+//! a.movdqu(x86::ptr(dst), vec0); // Store the result to [dst].
+//! a.emitEpilog(frame); // Emit function epilog and return.
+//!
+//! SumIntsFunc fn;
+//! Error err = rt.add(&fn, &code); // Add the generated code to the runtime.
+//! if (err) return 1; // Handle a possible error case.
+//!
+//! // Execute the generated function.
+//! int inA[4] = { 4, 3, 2, 1 };
+//! int inB[4] = { 1, 5, 2, 8 };
+//! int out[4];
+//! fn(out, inA, inB);
+//!
+//! // Prints {5 8 4 9}
+//! printf("{%d %d %d %d}\n", out[0], out[1], out[2], out[3]);
+//!
+//! rt.release(fn);
+//! return 0;
+//! }
+//! ```
+//!
+//! ### Using x86::Assembler as Code-Patcher
+//!
+//! This is an advanced topic that is sometimes unavoidable. AsmJit by default appends machine code it generates
+//! into a \ref CodeBuffer, however, it also allows to set the offset in \ref CodeBuffer explicitly and to overwrite
+//! its content. This technique is extremely dangerous as X86 instructions have variable length (see below), so you
+//! should in general only patch code to change instruction's immediate values or some other details not known the
+//! at a time the instruction was emitted. A typical scenario that requires code-patching is when you start emitting
+//! function and you don't know how much stack you want to reserve for it.
+//!
+//! Before we go further it's important to introduce instruction options, because they can help with code-patching
+//! (and not only patching, but that will be explained in AVX-512 section):
+//!
+//! - Many general-purpose instructions (especially arithmetic ones) on X86 have multiple encodings - in AsmJit
+//! this is usually called 'short form' and 'long form'.
+//!
+//! - AsmJit always tries to use 'short form' as it makes the resulting machine-code smaller, which is always
+//! good - this decision is used by majority of assemblers out there.
+//!
+//! - AsmJit allows to override the default decision by using `short_()` and `long_()` instruction options to force
+//! short or long form, respectively. The most useful is `long_()` as it basically forces AsmJit to always emit
+//! the longest form. The `short_()` is not that useful as it's automatic (except jumps to non-bound labels). Note
+//! that the underscore after each function name avoids collision with built-in C++ types.
+//!
+//! To illustrate what short form and long form means in binary let's assume we want to emit "add esp, 16" instruction,
+//! which has two possible binary encodings:
+//!
+//! - `83C410` - This is a short form aka `short add esp, 16` - You can see opcode byte (0x8C), MOD/RM byte (0xC4)
+//! and an 8-bit immediate value representing `16`.
+//!
+//! - `81C410000000` - This is a long form aka `long add esp, 16` - You can see a different opcode byte (0x81), the
+//! same Mod/RM byte (0xC4) and a 32-bit immediate in little-endian representing `16`.
+//!
+//! It should be obvious that patching an existing instruction into an instruction having a different size may create
+//! various problems. So it's recommended to be careful and to only patch instructions into instructions having the
+//! same size. The example below demonstrates how instruction options can be used to guarantee the size of an
+//! instruction by forcing the assembler to use long-form encoding:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//! #include <stdio.h>
+//!
+//! using namespace asmjit;
+//!
+//! typedef int (*Func)(void);
+//!
+//! int main(int argc, char* argv[]) {
+//! JitRuntime rt; // Create a runtime specialized for JIT.
+//! CodeHolder code; // Create a CodeHolder.
+//!
+//! code.init(rt.environment()); // Initialize code to match the JIT environment.
+//! x86::Assembler a(&code); // Create and attach x86::Assembler to code.
+//!
+//! // Let's get these registers from x86::Assembler.
+//! x86::Gp zbp = a.zbp();
+//! x86::Gp zsp = a.zsp();
+//!
+//! // Function prolog.
+//! a.push(zbp);
+//! a.mov(zbp, zsp);
+//!
+//! // This is where we are gonna patch the code later, so let's get the offset
+//! // (the current location) from the beginning of the code-buffer.
+//! size_t patchOffset = a.offset();
+//! // Let's just emit 'sub zsp, 0' for now, but don't forget to use LONG form.
+//! a.long_().sub(zsp, 0);
+//!
+//! // ... emit some code (this just sets return value to zero) ...
+//! a.xor_(x86::eax, x86::eax);
+//!
+//! // Function epilog and return.
+//! a.mov(zsp, zbp);
+//! a.pop(zbp);
+//! a.ret();
+//!
+//! // Now we know how much stack size we want to reserve. I have chosen 128
+//! // bytes on purpose as it's encodable only in long form that we have used.
+//!
+//! int stackSize = 128; // Number of bytes to reserve on the stack.
+//! a.setOffset(patchOffset); // Move the current cursor to `patchOffset`.
+//! a.long_().sub(zsp, stackSize); // Patch the code; don't forget to use LONG form.
+//!
+//! // Now the code is ready to be called
+//! Func fn;
+//! Error err = rt.add(&fn, &code); // Add the generated code to the runtime.
+//! if (err) return 1; // Handle a possible error returned by AsmJit.
+//!
+//! int result = fn(); // Execute the generated code.
+//! printf("%d\n", result); // Print the resulting "0".
+//!
+//! rt.release(fn); // Remove the function from the runtime.
+//! return 0;
+//! }
+//! ```
+//!
+//! If you run the example it will just work, because both instructions have the same size. As an experiment you can
+//! try removing `long_()` form to see what happens when wrong code is generated.
+//!
+//! ### Code Patching and REX Prefix
+//!
+//! In 64-bit mode there is one more thing to worry about when patching code: REX prefix. It's a single byte prefix
+//! designed to address registers with ids from 9 to 15 and to override the default width of operation from 32 to 64
+//! bits. AsmJit, like other assemblers, only emits REX prefix when it's necessary. If the patched code only changes
+//! the immediate value as shown in the previous example then there is nothing to worry about as it doesn't change
+//! the logic behind emitting REX prefix, however, if the patched code changes register id or overrides the operation
+//! width then it's important to take care of REX prefix as well.
+//!
+//! AsmJit contains another instruction option that controls (forces) REX prefix - `rex()`. If you use it the
+//! instruction emitted will always use REX prefix even when it's encodable without it. The following list contains
+//! some instructions and their binary representations to illustrate when it's emitted:
+//!
+//! - `__83C410` - `add esp, 16` - 32-bit operation in 64-bit mode doesn't require REX prefix.
+//! - `4083C410` - `rex add esp, 16` - 32-bit operation in 64-bit mode with forced REX prefix (0x40).
+//! - `4883C410` - `add rsp, 16` - 64-bit operation in 64-bit mode requires REX prefix (0x48).
+//! - `4183C410` - `add r12d, 16` - 32-bit operation in 64-bit mode using R12D requires REX prefix (0x41).
+//! - `4983C410` - `add r12, 16` - 64-bit operation in 64-bit mode using R12 requires REX prefix (0x49).
+//!
+//! ### More Prefixes
+//!
+//! X86 architecture is known for its prefixes. AsmJit supports all prefixes
+//! that can affect how the instruction is encoded:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//!
+//! using namespace asmjit;
+//!
+//! void prefixesExample(x86::Assembler& a) {
+//! // Lock prefix for implementing atomics:
+//! // lock add dword ptr [dst], 1
+//! a.lock().add(x86::dword_ptr(dst), 1);
+//!
+//! // Similarly, XAcquire/XRelease prefixes are also available:
+//! // xacquire add dword ptr [dst], 1
+//! a.xacquire().add(x86::dword_ptr(dst), 1);
+//!
+//! // Rep prefix (see also repe/repz and repne/repnz):
+//! // rep movs byte ptr [dst], byte ptr [src]
+//! a.rep().movs(x86::byte_ptr(dst), x86::byte_ptr(src));
+//!
+//! // Forcing REX prefix in 64-bit mode.
+//! // rex mov eax, 1
+//! a.rex().mov(x86::eax, 1);
+//!
+//! // AVX instruction without forced prefix uses the shortest encoding:
+//! // vaddpd xmm0, xmm1, xmm2 -> [C5|F1|58|C2]
+//! a.vaddpd(x86::xmm0, x86::xmm1, x86::xmm2);
+//!
+//! // Forcing VEX3 prefix (AVX):
+//! // vex3 vaddpd xmm0, xmm1, xmm2 -> [C4|E1|71|58|C2]
+//! a.vex3().vaddpd(x86::xmm0, x86::xmm1, x86::xmm2);
+//!
+//! // Forcing EVEX prefix (AVX512):
+//! // evex vaddpd xmm0, xmm1, xmm2 -> [62|F1|F5|08|58|C2]
+//! a.evex().vaddpd(x86::xmm0, x86::xmm1, x86::xmm2);
+//!
+//! // Some instructions accept prefixes not originally intended to:
+//! // rep ret
+//! a.rep().ret();
+//! }
+//! ```
+//!
+//! It's important to understand that prefixes are part of instruction options. When a member function that involves
+//! adding a prefix is called the prefix is combined with existing instruction options, which will affect the next
+//! instruction generated.
+//!
+//! ### Generating AVX512 code.
+//!
+//! x86::Assembler can generate AVX512+ code including the use of opmask registers. Opmask can be specified through
+//! \ref x86::Assembler::k() function, which stores it as an extra register, which will be used by the next
+//! instruction. AsmJit uses such concept for manipulating instruction options as well.
+//!
+//! The following AVX512 features are supported:
+//!
+//! - Opmask selector {k} and zeroing {z}.
+//! - Rounding modes {rn|rd|ru|rz} and suppress-all-exceptions {sae} option.
+//! - AVX512 broadcasts {1toN}.
+//!
+//! The following example demonstrates how AVX512 features can be used:
+//!
+//! ```
+//! #include <asmjit/x86.h>
+//!
+//! using namespace asmjit;
+//!
+//! void generateAVX512Code(x86::Assembler& a) {
+//! using namespace x86;
+//!
+//! // Opmask Selectors
+//! // ----------------
+//! //
+//! // - Opmask / zeroing is part of the instruction options / extraReg.
+//! // - k(reg) is like {kreg} in Intel syntax.
+//! // - z() is like {z} in Intel syntax.
+//!
+//! // vaddpd zmm {k1} {z}, zmm1, zmm2
+//! a.k(k1).z().vaddpd(zmm0, zmm1, zmm2);
+//!
+//! // Memory Broadcasts
+//! // -----------------
+//! //
+//! // - Broadcast data is part of memory operand.
+//! // - Use x86::Mem::_1toN(), which returns a new x86::Mem operand.
+//!
+//! // vaddpd zmm0 {k1} {z}, zmm1, [rcx] {1to8}
+//! a.k(k1).z().vaddpd(zmm0, zmm1, x86::mem(rcx)._1to8());
+//!
+//! // Embedded Rounding & Suppress-All-Exceptoins
+//! // -------------------------------------------
+//! //
+//! // - Rounding mode and {sae} are part of instruction options.
+//! // - Use sae() to enable exception suppression.
+//! // - Use rn_sae(), rd_sae(), ru_sae(), and rz_sae() - to enable rounding.
+//! // - Embedded rounding implicitly sets {sae} as well, that's why the API
+//! // also has sae() suffix, to make it clear.
+//!
+//! // vcmppd k1, zmm1, zmm2, 0x00 {sae}
+//! a.sae().vcmppd(k1, zmm1, zmm2, 0);
+//!
+//! // vaddpd zmm0, zmm1, zmm2 {rz}
+//! a.rz_sae().vaddpd(zmm0, zmm1, zmm2);
+//! }
+//! ```
+class ASMJIT_VIRTAPI Assembler
+ : public BaseAssembler,
+ public EmitterImplicitT<Assembler> {
+public:
+ ASMJIT_NONCOPYABLE(Assembler)
+ typedef BaseAssembler Base;
+
+ //! \name Construction & Destruction
+ //! \{
+
+ ASMJIT_API explicit Assembler(CodeHolder* code = nullptr) noexcept;
+ ASMJIT_API virtual ~Assembler() noexcept;
+
+ //! \}
+
+ //! \cond INTERNAL
+ //! \name Internal
+ //! \{
+
+ // NOTE: x86::Assembler uses _privateData to store 'address-override' bit that is used to decide whether to emit
+ // address-override (67H) prefix based on the memory BASE+INDEX registers. It's either `kX86MemInfo_67H_X86` or
+ // `kX86MemInfo_67H_X64`.
+ inline uint32_t _addressOverrideMask() const noexcept { return _privateData; }
+ inline void _setAddressOverrideMask(uint32_t m) noexcept { _privateData = m; }
+
+ //! \}
+ //! \endcond
+
+ //! \name Emit
+ //! \{
+
+ ASMJIT_API Error _emit(InstId instId, const Operand_& o0, const Operand_& o1, const Operand_& o2, const Operand_* opExt) override;
+
+ //! \}
+ //! \endcond
+
+ //! \name Align
+ //! \{
+
+ ASMJIT_API Error align(AlignMode alignMode, uint32_t alignment) override;
+
+ //! \}
+
+ //! \name Events
+ //! \{
+
+ ASMJIT_API Error onAttach(CodeHolder* code) noexcept override;
+ ASMJIT_API Error onDetach(CodeHolder* code) noexcept override;
+
+ //! \}
+};
+
+//! \}
+
+ASMJIT_END_SUB_NAMESPACE
+
+#endif // ASMJIT_X86_X86ASSEMBLER_H_INCLUDED