// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details #pragma once #include "Luau/AssemblyBuilderA64.h" #include "EmitCommon.h" #include "lobject.h" #include "ltm.h" #include "lstate.h" // AArch64 ABI reminder: // Arguments: x0-x7, v0-v7 // Return: x0, v0 (or x8 that points to the address of the resulting structure) // Volatile: x9-x15, v16-v31 ("caller-saved", any call may change them) // Non-volatile: x19-x28, v8-v15 ("callee-saved", preserved after calls, only bottom half of SIMD registers is preserved!) // Reserved: x16-x18: reserved for linker/platform use; x29: frame pointer (unless omitted); x30: link register; x31: stack pointer namespace Luau { namespace CodeGen { struct NativeState; namespace A64 { // Data that is very common to access is placed in non-volatile registers: // 1. Constant registers (only loaded during codegen entry) constexpr RegisterA64 rState = x19; // lua_State* L constexpr RegisterA64 rNativeContext = x20; // NativeContext* context // 2. Frame registers (reloaded when call frame changes; rBase is also reloaded after all calls that may reallocate stack) constexpr RegisterA64 rConstants = x21; // TValue* k constexpr RegisterA64 rClosure = x22; // Closure* cl constexpr RegisterA64 rCode = x23; // Instruction* code constexpr RegisterA64 rBase = x24; // StkId base // Native code is as stackless as the interpreter, so we can place some data on the stack once and have it accessible at any point // See CodeGenA64.cpp for layout constexpr unsigned kStashSlots = 8; // stashed non-volatile registers constexpr unsigned kSpillSlots = 0; // slots for spilling temporary registers (unused) constexpr unsigned kTempSlots = 2; // 16 bytes of temporary space, such luxury! constexpr unsigned kStackSize = (kStashSlots + kSpillSlots + kTempSlots) * 8; constexpr AddressA64 sSpillArea = mem(sp, kStashSlots * 8); constexpr AddressA64 sTemporary = mem(sp, (kStashSlots + kSpillSlots) * 8); inline void emitUpdateBase(AssemblyBuilderA64& build) { build.ldr(rBase, mem(rState, offsetof(lua_State, base))); } } // namespace A64 } // namespace CodeGen } // namespace Luau