3502 lines
118 KiB
C++
3502 lines
118 KiB
C++
// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
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#include "Luau/Compiler.h"
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#include "Luau/Parser.h"
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#include "Luau/BytecodeBuilder.h"
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#include "Luau/Common.h"
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#include "Luau/TimeTrace.h"
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#include "Builtins.h"
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#include "ConstantFolding.h"
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#include "CostModel.h"
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#include "TableShape.h"
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#include "ValueTracking.h"
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#include <algorithm>
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#include <bitset>
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#include <math.h>
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#include <limits.h>
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LUAU_FASTFLAGVARIABLE(LuauCompileSupportInlining, false)
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LUAU_FASTFLAGVARIABLE(LuauCompileIter, false)
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LUAU_FASTFLAGVARIABLE(LuauCompileIterNoReserve, false)
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LUAU_FASTFLAGVARIABLE(LuauCompileIterNoPairs, false)
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LUAU_FASTINTVARIABLE(LuauCompileLoopUnrollThreshold, 25)
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LUAU_FASTINTVARIABLE(LuauCompileLoopUnrollThresholdMaxBoost, 300)
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LUAU_FASTINTVARIABLE(LuauCompileInlineThreshold, 25)
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LUAU_FASTINTVARIABLE(LuauCompileInlineThresholdMaxBoost, 300)
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LUAU_FASTINTVARIABLE(LuauCompileInlineDepth, 5)
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namespace Luau
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{
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using namespace Luau::Compile;
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static const uint32_t kMaxRegisterCount = 255;
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static const uint32_t kMaxUpvalueCount = 200;
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static const uint32_t kMaxLocalCount = 200;
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CompileError::CompileError(const Location& location, const std::string& message)
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: location(location)
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, message(message)
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{
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}
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CompileError::~CompileError() throw() {}
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const char* CompileError::what() const throw()
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{
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return message.c_str();
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}
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const Location& CompileError::getLocation() const
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{
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return location;
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}
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// NOINLINE is used to limit the stack cost of this function due to std::string object / exception plumbing
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LUAU_NOINLINE void CompileError::raise(const Location& location, const char* format, ...)
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{
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va_list args;
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va_start(args, format);
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std::string message = vformat(format, args);
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va_end(args);
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throw CompileError(location, message);
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}
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static BytecodeBuilder::StringRef sref(AstName name)
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{
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LUAU_ASSERT(name.value);
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return {name.value, strlen(name.value)};
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}
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static BytecodeBuilder::StringRef sref(AstArray<char> data)
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{
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LUAU_ASSERT(data.data);
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return {data.data, data.size};
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}
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struct Compiler
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{
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struct RegScope;
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Compiler(BytecodeBuilder& bytecode, const CompileOptions& options)
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: bytecode(bytecode)
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, options(options)
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, functions(nullptr)
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, locals(nullptr)
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, globals(AstName())
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, variables(nullptr)
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, constants(nullptr)
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, locstants(nullptr)
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, tableShapes(nullptr)
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{
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// preallocate some buffers that are very likely to grow anyway; this works around std::vector's inefficient growth policy for small arrays
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localStack.reserve(16);
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upvals.reserve(16);
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}
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uint8_t getLocal(AstLocal* local)
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{
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Local* l = locals.find(local);
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LUAU_ASSERT(l);
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LUAU_ASSERT(l->allocated);
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return l->reg;
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}
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uint8_t getUpval(AstLocal* local)
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{
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for (size_t uid = 0; uid < upvals.size(); ++uid)
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if (upvals[uid] == local)
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return uint8_t(uid);
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if (upvals.size() >= kMaxUpvalueCount)
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CompileError::raise(
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local->location, "Out of upvalue registers when trying to allocate %s: exceeded limit %d", local->name.value, kMaxUpvalueCount);
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// mark local as captured so that closeLocals emits LOP_CLOSEUPVALS accordingly
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Variable* v = variables.find(local);
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if (v && v->written)
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locals[local].captured = true;
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upvals.push_back(local);
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return uint8_t(upvals.size() - 1);
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}
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bool allPathsEndWithReturn(AstStat* node)
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{
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if (AstStatBlock* stat = node->as<AstStatBlock>())
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return stat->body.size > 0 && allPathsEndWithReturn(stat->body.data[stat->body.size - 1]);
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else if (node->is<AstStatReturn>())
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return true;
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else if (AstStatIf* stat = node->as<AstStatIf>())
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return stat->elsebody && allPathsEndWithReturn(stat->thenbody) && allPathsEndWithReturn(stat->elsebody);
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else
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return false;
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}
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void emitLoadK(uint8_t target, int32_t cid)
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{
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LUAU_ASSERT(cid >= 0);
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if (cid < 32768)
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{
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bytecode.emitAD(LOP_LOADK, target, int16_t(cid));
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}
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else
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{
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bytecode.emitAD(LOP_LOADKX, target, 0);
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bytecode.emitAux(cid);
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}
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}
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AstExprFunction* getFunctionExpr(AstExpr* node)
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{
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if (AstExprLocal* le = node->as<AstExprLocal>())
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{
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Variable* lv = variables.find(le->local);
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if (!lv || lv->written || !lv->init)
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return nullptr;
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return getFunctionExpr(lv->init);
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}
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else if (AstExprGroup* ge = node->as<AstExprGroup>())
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return getFunctionExpr(ge->expr);
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else
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return node->as<AstExprFunction>();
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}
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bool canInlineFunctionBody(AstStat* stat)
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{
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struct CanInlineVisitor : AstVisitor
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{
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bool result = true;
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bool visit(AstExpr* node) override
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{
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// nested functions may capture function arguments, and our upval handling doesn't handle elided variables (constant)
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// TODO: we could remove this case if we changed function compilation to create temporary locals for constant upvalues
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// TODO: additionally we would need to change upvalue handling in compileExprFunction to handle upvalue->local migration
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result = result && !node->is<AstExprFunction>();
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return result;
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}
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bool visit(AstStat* node) override
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{
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// loops may need to be unrolled which can result in cost amplification
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result = result && !node->is<AstStatFor>();
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return result;
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}
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};
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CanInlineVisitor canInline;
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stat->visit(&canInline);
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return canInline.result;
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}
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uint32_t compileFunction(AstExprFunction* func)
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{
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LUAU_TIMETRACE_SCOPE("Compiler::compileFunction", "Compiler");
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if (func->debugname.value)
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LUAU_TIMETRACE_ARGUMENT("name", func->debugname.value);
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LUAU_ASSERT(!functions.contains(func));
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LUAU_ASSERT(regTop == 0 && stackSize == 0 && localStack.empty() && upvals.empty());
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RegScope rs(this);
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bool self = func->self != 0;
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uint32_t fid = bytecode.beginFunction(uint8_t(self + func->args.size), func->vararg);
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setDebugLine(func);
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if (func->vararg)
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bytecode.emitABC(LOP_PREPVARARGS, uint8_t(self + func->args.size), 0, 0);
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uint8_t args = allocReg(func, self + unsigned(func->args.size));
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if (func->self)
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pushLocal(func->self, args);
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for (size_t i = 0; i < func->args.size; ++i)
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pushLocal(func->args.data[i], uint8_t(args + self + i));
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AstStatBlock* stat = func->body;
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for (size_t i = 0; i < stat->body.size; ++i)
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compileStat(stat->body.data[i]);
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// valid function bytecode must always end with RETURN
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// we elide this if we're guaranteed to hit a RETURN statement regardless of the control flow
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if (!allPathsEndWithReturn(stat))
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{
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setDebugLineEnd(stat);
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closeLocals(0);
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bytecode.emitABC(LOP_RETURN, 0, 1, 0);
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}
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// constant folding may remove some upvalue refs from bytecode, so this puts them back
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if (options.optimizationLevel >= 1 && options.debugLevel >= 2)
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gatherConstUpvals(func);
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bytecode.setDebugFunctionLineDefined(func->location.begin.line + 1);
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if (options.debugLevel >= 1 && func->debugname.value)
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bytecode.setDebugFunctionName(sref(func->debugname));
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if (options.debugLevel >= 2 && !upvals.empty())
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{
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for (AstLocal* l : upvals)
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bytecode.pushDebugUpval(sref(l->name));
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}
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if (options.optimizationLevel >= 1)
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bytecode.foldJumps();
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bytecode.expandJumps();
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popLocals(0);
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bytecode.endFunction(uint8_t(stackSize), uint8_t(upvals.size()));
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Function& f = functions[func];
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f.id = fid;
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f.upvals = upvals;
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// record information for inlining
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if (FFlag::LuauCompileSupportInlining && options.optimizationLevel >= 2 && !func->vararg && canInlineFunctionBody(func->body) &&
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!getfenvUsed && !setfenvUsed)
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{
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f.canInline = true;
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f.stackSize = stackSize;
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f.costModel = modelCost(func->body, func->args.data, func->args.size);
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}
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upvals.clear(); // note: instead of std::move above, we copy & clear to preserve capacity for future pushes
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stackSize = 0;
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return fid;
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}
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// note: this doesn't just clobber target (assuming it's temp), but also clobbers *all* allocated registers >= target!
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// this is important to be able to support "multret" semantics due to Lua call frame structure
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bool compileExprTempMultRet(AstExpr* node, uint8_t target)
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{
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if (AstExprCall* expr = node->as<AstExprCall>())
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{
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// We temporarily swap out regTop to have targetTop work correctly...
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// This is a crude hack but it's necessary for correctness :(
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RegScope rs(this, target);
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compileExprCall(expr, target, /* targetCount= */ 0, /* targetTop= */ true, /* multRet= */ true);
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return true;
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}
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else if (AstExprVarargs* expr = node->as<AstExprVarargs>())
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{
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// We temporarily swap out regTop to have targetTop work correctly...
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// This is a crude hack but it's necessary for correctness :(
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RegScope rs(this, target);
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compileExprVarargs(expr, target, /* targetCount= */ 0, /* multRet= */ true);
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return true;
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}
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else
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{
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compileExprTemp(node, target);
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return false;
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}
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}
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// note: this doesn't just clobber target (assuming it's temp), but also clobbers *all* allocated registers >= target!
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// this is important to be able to emit code that takes fewer registers and runs faster
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void compileExprTempTop(AstExpr* node, uint8_t target)
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{
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// We temporarily swap out regTop to have targetTop work correctly...
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// This is a crude hack but it's necessary for performance :(
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// It makes sure that nested call expressions can use targetTop optimization and don't need to have too many registers
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RegScope rs(this, target + 1);
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compileExprTemp(node, target);
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}
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void compileExprVarargs(AstExprVarargs* expr, uint8_t target, uint8_t targetCount, bool multRet = false)
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{
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LUAU_ASSERT(!multRet || unsigned(target + targetCount) == regTop);
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setDebugLine(expr); // normally compileExpr sets up line info, but compileExprCall can be called directly
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bytecode.emitABC(LOP_GETVARARGS, target, multRet ? 0 : uint8_t(targetCount + 1), 0);
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}
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void compileExprSelectVararg(AstExprCall* expr, uint8_t target, uint8_t targetCount, bool targetTop, bool multRet, uint8_t regs)
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{
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LUAU_ASSERT(targetCount == 1);
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LUAU_ASSERT(!expr->self);
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LUAU_ASSERT(expr->args.size == 2 && expr->args.data[1]->is<AstExprVarargs>());
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AstExpr* arg = expr->args.data[0];
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uint8_t argreg;
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if (isExprLocalReg(arg))
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argreg = getLocal(arg->as<AstExprLocal>()->local);
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else
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{
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argreg = uint8_t(regs + 1);
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compileExprTempTop(arg, argreg);
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}
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size_t fastcallLabel = bytecode.emitLabel();
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bytecode.emitABC(LOP_FASTCALL1, LBF_SELECT_VARARG, argreg, 0);
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// note, these instructions are normally not executed and are used as a fallback for FASTCALL
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// we can't use TempTop variant here because we need to make sure the arguments we already computed aren't overwritten
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compileExprTemp(expr->func, regs);
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if (argreg != regs + 1)
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bytecode.emitABC(LOP_MOVE, uint8_t(regs + 1), argreg, 0);
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bytecode.emitABC(LOP_GETVARARGS, uint8_t(regs + 2), 0, 0);
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size_t callLabel = bytecode.emitLabel();
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if (!bytecode.patchSkipC(fastcallLabel, callLabel))
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CompileError::raise(expr->func->location, "Exceeded jump distance limit; simplify the code to compile");
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// note, this is always multCall (last argument is variadic)
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bytecode.emitABC(LOP_CALL, regs, 0, multRet ? 0 : uint8_t(targetCount + 1));
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// if we didn't output results directly to target, we need to move them
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if (!targetTop)
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{
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for (size_t i = 0; i < targetCount; ++i)
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bytecode.emitABC(LOP_MOVE, uint8_t(target + i), uint8_t(regs + i), 0);
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}
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}
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void compileExprFastcallN(AstExprCall* expr, uint8_t target, uint8_t targetCount, bool targetTop, bool multRet, uint8_t regs, int bfid)
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{
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LUAU_ASSERT(!expr->self);
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LUAU_ASSERT(expr->args.size <= 2);
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LuauOpcode opc = expr->args.size == 1 ? LOP_FASTCALL1 : LOP_FASTCALL2;
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uint32_t args[2] = {};
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for (size_t i = 0; i < expr->args.size; ++i)
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{
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if (i > 0)
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{
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if (int32_t cid = getConstantIndex(expr->args.data[i]); cid >= 0)
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{
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opc = LOP_FASTCALL2K;
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args[i] = cid;
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break;
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}
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}
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if (isExprLocalReg(expr->args.data[i]))
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args[i] = getLocal(expr->args.data[i]->as<AstExprLocal>()->local);
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else
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{
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args[i] = uint8_t(regs + 1 + i);
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compileExprTempTop(expr->args.data[i], uint8_t(args[i]));
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}
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}
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size_t fastcallLabel = bytecode.emitLabel();
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bytecode.emitABC(opc, uint8_t(bfid), uint8_t(args[0]), 0);
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if (opc != LOP_FASTCALL1)
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bytecode.emitAux(args[1]);
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// Set up a traditional Lua stack for the subsequent LOP_CALL.
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// Note, as with other instructions that immediately follow FASTCALL, these are normally not executed and are used as a fallback for
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// these FASTCALL variants.
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for (size_t i = 0; i < expr->args.size; ++i)
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{
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if (i > 0 && opc == LOP_FASTCALL2K)
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{
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emitLoadK(uint8_t(regs + 1 + i), args[i]);
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break;
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}
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if (args[i] != regs + 1 + i)
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bytecode.emitABC(LOP_MOVE, uint8_t(regs + 1 + i), uint8_t(args[i]), 0);
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}
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// note, these instructions are normally not executed and are used as a fallback for FASTCALL
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// we can't use TempTop variant here because we need to make sure the arguments we already computed aren't overwritten
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compileExprTemp(expr->func, regs);
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size_t callLabel = bytecode.emitLabel();
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// FASTCALL will skip over the instructions needed to compute function and jump over CALL which must immediately follow the instruction
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// sequence after FASTCALL
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if (!bytecode.patchSkipC(fastcallLabel, callLabel))
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CompileError::raise(expr->func->location, "Exceeded jump distance limit; simplify the code to compile");
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bytecode.emitABC(LOP_CALL, regs, uint8_t(expr->args.size + 1), multRet ? 0 : uint8_t(targetCount + 1));
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// if we didn't output results directly to target, we need to move them
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if (!targetTop)
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{
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for (size_t i = 0; i < targetCount; ++i)
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bytecode.emitABC(LOP_MOVE, uint8_t(target + i), uint8_t(regs + i), 0);
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}
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}
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bool tryCompileInlinedCall(AstExprCall* expr, AstExprFunction* func, uint8_t target, uint8_t targetCount, bool multRet, int thresholdBase,
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int thresholdMaxBoost, int depthLimit)
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{
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Function* fi = functions.find(func);
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LUAU_ASSERT(fi);
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// make sure we have enough register space
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if (regTop > 128 || fi->stackSize > 32)
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{
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bytecode.addDebugRemark("inlining failed: high register pressure");
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return false;
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}
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// we should ideally aggregate the costs during recursive inlining, but for now simply limit the depth
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if (int(inlineFrames.size()) >= depthLimit)
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{
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bytecode.addDebugRemark("inlining failed: too many inlined frames");
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return false;
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}
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// compiling recursive inlining is difficult because we share constant/variable state but need to bind variables to different registers
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for (InlineFrame& frame : inlineFrames)
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if (frame.func == func)
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{
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bytecode.addDebugRemark("inlining failed: can't inline recursive calls");
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return false;
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}
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// TODO: we can compile multret functions if all returns of the function are multret as well
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if (multRet)
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{
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bytecode.addDebugRemark("inlining failed: can't convert fixed returns to multret");
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return false;
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}
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// TODO: we can compile functions with mismatching arity at call site but it's more annoying
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if (func->args.size != expr->args.size)
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{
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bytecode.addDebugRemark("inlining failed: argument count mismatch (expected %d, got %d)", int(func->args.size), int(expr->args.size));
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return false;
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}
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// we use a dynamic cost threshold that's based on the fixed limit boosted by the cost advantage we gain due to inlining
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|
bool varc[8] = {};
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for (size_t i = 0; i < expr->args.size && i < 8; ++i)
|
|
varc[i] = isConstant(expr->args.data[i]);
|
|
|
|
int inlinedCost = computeCost(fi->costModel, varc, std::min(int(expr->args.size), 8));
|
|
int baselineCost = computeCost(fi->costModel, nullptr, 0) + 3;
|
|
int inlineProfit = (inlinedCost == 0) ? thresholdMaxBoost : std::min(thresholdMaxBoost, 100 * baselineCost / inlinedCost);
|
|
|
|
int threshold = thresholdBase * inlineProfit / 100;
|
|
|
|
if (inlinedCost > threshold)
|
|
{
|
|
bytecode.addDebugRemark("inlining failed: too expensive (cost %d, profit %.2fx)", inlinedCost, double(inlineProfit) / 100);
|
|
return false;
|
|
}
|
|
|
|
bytecode.addDebugRemark(
|
|
"inlining succeeded (cost %d, profit %.2fx, depth %d)", inlinedCost, double(inlineProfit) / 100, int(inlineFrames.size()));
|
|
|
|
compileInlinedCall(expr, func, target, targetCount);
|
|
return true;
|
|
}
|
|
|
|
void compileInlinedCall(AstExprCall* expr, AstExprFunction* func, uint8_t target, uint8_t targetCount)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
size_t oldLocals = localStack.size();
|
|
|
|
// note that we push the frame early; this is needed to block recursive inline attempts
|
|
inlineFrames.push_back({func, target, targetCount});
|
|
|
|
// evaluate all arguments; note that we don't emit code for constant arguments (relying on constant folding)
|
|
for (size_t i = 0; i < func->args.size; ++i)
|
|
{
|
|
AstLocal* var = func->args.data[i];
|
|
AstExpr* arg = expr->args.data[i];
|
|
|
|
if (Variable* vv = variables.find(var); vv && vv->written)
|
|
{
|
|
// if the argument is mutated, we need to allocate a fresh register even if it's a constant
|
|
uint8_t reg = allocReg(arg, 1);
|
|
compileExprTemp(arg, reg);
|
|
pushLocal(var, reg);
|
|
}
|
|
else if (const Constant* cv = constants.find(arg); cv && cv->type != Constant::Type_Unknown)
|
|
{
|
|
// since the argument is not mutated, we can simply fold the value into the expressions that need it
|
|
locstants[var] = *cv;
|
|
}
|
|
else
|
|
{
|
|
AstExprLocal* le = arg->as<AstExprLocal>();
|
|
Variable* lv = le ? variables.find(le->local) : nullptr;
|
|
|
|
// if the argument is a local that isn't mutated, we will simply reuse the existing register
|
|
if (isExprLocalReg(arg) && (!lv || !lv->written))
|
|
{
|
|
uint8_t reg = getLocal(le->local);
|
|
pushLocal(var, reg);
|
|
}
|
|
else
|
|
{
|
|
uint8_t reg = allocReg(arg, 1);
|
|
compileExprTemp(arg, reg);
|
|
pushLocal(var, reg);
|
|
}
|
|
}
|
|
}
|
|
|
|
// fold constant values updated above into expressions in the function body
|
|
foldConstants(constants, variables, locstants, func->body);
|
|
|
|
bool usedFallthrough = false;
|
|
|
|
for (size_t i = 0; i < func->body->body.size; ++i)
|
|
{
|
|
AstStat* stat = func->body->body.data[i];
|
|
|
|
if (AstStatReturn* ret = stat->as<AstStatReturn>())
|
|
{
|
|
// Optimization: use fallthrough when compiling return at the end of the function to avoid an extra JUMP
|
|
compileInlineReturn(ret, /* fallthrough= */ true);
|
|
// TODO: This doesn't work when return is part of control flow; ideally we would track the state somehow and generalize this
|
|
usedFallthrough = true;
|
|
break;
|
|
}
|
|
else
|
|
compileStat(stat);
|
|
}
|
|
|
|
// for the fallthrough path we need to ensure we clear out target registers
|
|
if (!usedFallthrough && !allPathsEndWithReturn(func->body))
|
|
{
|
|
for (size_t i = 0; i < targetCount; ++i)
|
|
bytecode.emitABC(LOP_LOADNIL, uint8_t(target + i), 0, 0);
|
|
}
|
|
|
|
popLocals(oldLocals);
|
|
|
|
size_t returnLabel = bytecode.emitLabel();
|
|
patchJumps(expr, inlineFrames.back().returnJumps, returnLabel);
|
|
|
|
inlineFrames.pop_back();
|
|
|
|
// clean up constant state for future inlining attempts
|
|
for (size_t i = 0; i < func->args.size; ++i)
|
|
if (Constant* var = locstants.find(func->args.data[i]))
|
|
var->type = Constant::Type_Unknown;
|
|
|
|
foldConstants(constants, variables, locstants, func->body);
|
|
}
|
|
|
|
void compileExprCall(AstExprCall* expr, uint8_t target, uint8_t targetCount, bool targetTop = false, bool multRet = false)
|
|
{
|
|
LUAU_ASSERT(!targetTop || unsigned(target + targetCount) == regTop);
|
|
|
|
setDebugLine(expr); // normally compileExpr sets up line info, but compileExprCall can be called directly
|
|
|
|
// try inlining the function
|
|
if (options.optimizationLevel >= 2 && !expr->self)
|
|
{
|
|
AstExprFunction* func = getFunctionExpr(expr->func);
|
|
Function* fi = func ? functions.find(func) : nullptr;
|
|
|
|
if (fi && fi->canInline &&
|
|
tryCompileInlinedCall(expr, func, target, targetCount, multRet, FInt::LuauCompileInlineThreshold,
|
|
FInt::LuauCompileInlineThresholdMaxBoost, FInt::LuauCompileInlineDepth))
|
|
return;
|
|
|
|
if (fi && !fi->canInline)
|
|
bytecode.addDebugRemark("inlining failed: complex constructs in function body");
|
|
}
|
|
|
|
RegScope rs(this);
|
|
|
|
unsigned int regCount = std::max(unsigned(1 + expr->self + expr->args.size), unsigned(targetCount));
|
|
|
|
// Optimization: if target points to the top of the stack, we can start the call at oldTop - 1 and won't need MOVE at the end
|
|
uint8_t regs = targetTop ? allocReg(expr, regCount - targetCount) - targetCount : allocReg(expr, regCount);
|
|
|
|
uint8_t selfreg = 0;
|
|
|
|
int bfid = -1;
|
|
|
|
if (options.optimizationLevel >= 1)
|
|
{
|
|
Builtin builtin = getBuiltin(expr->func, globals, variables);
|
|
bfid = getBuiltinFunctionId(builtin, options);
|
|
}
|
|
|
|
if (bfid == LBF_SELECT_VARARG)
|
|
{
|
|
// Optimization: compile select(_, ...) as FASTCALL1; the builtin will read variadic arguments directly
|
|
// note: for now we restrict this to single-return expressions since our runtime code doesn't deal with general cases
|
|
if (multRet == false && targetCount == 1 && expr->args.size == 2 && expr->args.data[1]->is<AstExprVarargs>())
|
|
return compileExprSelectVararg(expr, target, targetCount, targetTop, multRet, regs);
|
|
else
|
|
bfid = -1;
|
|
}
|
|
|
|
// Optimization: for 1/2 argument fast calls use specialized opcodes
|
|
if (!expr->self && bfid >= 0 && expr->args.size >= 1 && expr->args.size <= 2)
|
|
{
|
|
AstExpr* last = expr->args.data[expr->args.size - 1];
|
|
if (!last->is<AstExprCall>() && !last->is<AstExprVarargs>())
|
|
return compileExprFastcallN(expr, target, targetCount, targetTop, multRet, regs, bfid);
|
|
}
|
|
|
|
if (expr->self)
|
|
{
|
|
AstExprIndexName* fi = expr->func->as<AstExprIndexName>();
|
|
LUAU_ASSERT(fi);
|
|
|
|
// Optimization: use local register directly in NAMECALL if possible
|
|
if (isExprLocalReg(fi->expr))
|
|
{
|
|
selfreg = getLocal(fi->expr->as<AstExprLocal>()->local);
|
|
}
|
|
else
|
|
{
|
|
// Note: to be able to compile very deeply nested self call chains (obj:method1():method2():...), we need to be able to do this in
|
|
// finite stack space NAMECALL will happily move object from regs to regs+1 but we need to compute it into regs so that
|
|
// compileExprTempTop doesn't increase stack usage for every recursive call
|
|
selfreg = regs;
|
|
|
|
compileExprTempTop(fi->expr, selfreg);
|
|
}
|
|
}
|
|
else if (bfid < 0)
|
|
{
|
|
compileExprTempTop(expr->func, regs);
|
|
}
|
|
|
|
bool multCall = false;
|
|
|
|
for (size_t i = 0; i < expr->args.size; ++i)
|
|
if (i + 1 == expr->args.size)
|
|
multCall = compileExprTempMultRet(expr->args.data[i], uint8_t(regs + 1 + expr->self + i));
|
|
else
|
|
compileExprTempTop(expr->args.data[i], uint8_t(regs + 1 + expr->self + i));
|
|
|
|
setDebugLineEnd(expr->func);
|
|
|
|
if (expr->self)
|
|
{
|
|
AstExprIndexName* fi = expr->func->as<AstExprIndexName>();
|
|
LUAU_ASSERT(fi);
|
|
|
|
setDebugLine(fi->indexLocation);
|
|
|
|
BytecodeBuilder::StringRef iname = sref(fi->index);
|
|
int32_t cid = bytecode.addConstantString(iname);
|
|
if (cid < 0)
|
|
CompileError::raise(fi->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
bytecode.emitABC(LOP_NAMECALL, regs, selfreg, uint8_t(BytecodeBuilder::getStringHash(iname)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
else if (bfid >= 0)
|
|
{
|
|
size_t fastcallLabel = bytecode.emitLabel();
|
|
bytecode.emitABC(LOP_FASTCALL, uint8_t(bfid), 0, 0);
|
|
|
|
// note, these instructions are normally not executed and are used as a fallback for FASTCALL
|
|
// we can't use TempTop variant here because we need to make sure the arguments we already computed aren't overwritten
|
|
compileExprTemp(expr->func, regs);
|
|
|
|
size_t callLabel = bytecode.emitLabel();
|
|
|
|
// FASTCALL will skip over the instructions needed to compute function and jump over CALL which must immediately follow the instruction
|
|
// sequence after FASTCALL
|
|
if (!bytecode.patchSkipC(fastcallLabel, callLabel))
|
|
CompileError::raise(expr->func->location, "Exceeded jump distance limit; simplify the code to compile");
|
|
}
|
|
|
|
bytecode.emitABC(LOP_CALL, regs, multCall ? 0 : uint8_t(expr->self + expr->args.size + 1), multRet ? 0 : uint8_t(targetCount + 1));
|
|
|
|
// if we didn't output results directly to target, we need to move them
|
|
if (!targetTop)
|
|
{
|
|
for (size_t i = 0; i < targetCount; ++i)
|
|
bytecode.emitABC(LOP_MOVE, uint8_t(target + i), uint8_t(regs + i), 0);
|
|
}
|
|
}
|
|
|
|
bool shouldShareClosure(AstExprFunction* func)
|
|
{
|
|
const Function* f = functions.find(func);
|
|
if (!f)
|
|
return false;
|
|
|
|
for (AstLocal* uv : f->upvals)
|
|
{
|
|
Variable* ul = variables.find(uv);
|
|
|
|
if (!ul)
|
|
return false;
|
|
|
|
if (ul->written)
|
|
return false;
|
|
|
|
// it's technically safe to share closures whenever all upvalues are immutable
|
|
// this is because of a runtime equality check in DUPCLOSURE.
|
|
// however, this results in frequent deoptimization and increases the set of reachable objects, making some temporary objects permanent
|
|
// instead we apply a heuristic: we share closures if they refer to top-level upvalues, or closures that refer to top-level upvalues
|
|
// this will only deoptimize (outside of fenv changes) if top level code is executed twice with different results.
|
|
if (uv->functionDepth != 0 || uv->loopDepth != 0)
|
|
{
|
|
AstExprFunction* uf = ul->init ? ul->init->as<AstExprFunction>() : nullptr;
|
|
if (!uf)
|
|
return false;
|
|
|
|
if (uf != func && !shouldShareClosure(uf))
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void compileExprFunction(AstExprFunction* expr, uint8_t target)
|
|
{
|
|
const Function* f = functions.find(expr);
|
|
LUAU_ASSERT(f);
|
|
|
|
// when the closure has upvalues we'll use this to create the closure at runtime
|
|
// when the closure has no upvalues, we use constant closures that technically don't rely on the child function list
|
|
// however, it's still important to add the child function because debugger relies on the function hierarchy when setting breakpoints
|
|
int16_t pid = bytecode.addChildFunction(f->id);
|
|
if (pid < 0)
|
|
CompileError::raise(expr->location, "Exceeded closure limit; simplify the code to compile");
|
|
|
|
bool shared = false;
|
|
|
|
// Optimization: when closure has no upvalues, or upvalues are safe to share, instead of allocating it every time we can share closure
|
|
// objects (this breaks assumptions about function identity which can lead to setfenv not working as expected, so we disable this when it
|
|
// is used)
|
|
if (options.optimizationLevel >= 1 && shouldShareClosure(expr) && !setfenvUsed)
|
|
{
|
|
int32_t cid = bytecode.addConstantClosure(f->id);
|
|
|
|
if (cid >= 0 && cid < 32768)
|
|
{
|
|
bytecode.emitAD(LOP_DUPCLOSURE, target, int16_t(cid));
|
|
shared = true;
|
|
}
|
|
}
|
|
|
|
if (!shared)
|
|
bytecode.emitAD(LOP_NEWCLOSURE, target, pid);
|
|
|
|
for (AstLocal* uv : f->upvals)
|
|
{
|
|
LUAU_ASSERT(uv->functionDepth < expr->functionDepth);
|
|
|
|
Variable* ul = variables.find(uv);
|
|
bool immutable = !ul || !ul->written;
|
|
|
|
if (uv->functionDepth == expr->functionDepth - 1)
|
|
{
|
|
// get local variable
|
|
uint8_t reg = getLocal(uv);
|
|
|
|
bytecode.emitABC(LOP_CAPTURE, uint8_t(immutable ? LCT_VAL : LCT_REF), reg, 0);
|
|
}
|
|
else
|
|
{
|
|
// get upvalue from parent frame
|
|
// note: this will add uv to the current upvalue list if necessary
|
|
uint8_t uid = getUpval(uv);
|
|
|
|
bytecode.emitABC(LOP_CAPTURE, LCT_UPVAL, uid, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
LuauOpcode getUnaryOp(AstExprUnary::Op op)
|
|
{
|
|
switch (op)
|
|
{
|
|
case AstExprUnary::Not:
|
|
return LOP_NOT;
|
|
|
|
case AstExprUnary::Minus:
|
|
return LOP_MINUS;
|
|
|
|
case AstExprUnary::Len:
|
|
return LOP_LENGTH;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected unary operation");
|
|
return LOP_NOP;
|
|
}
|
|
}
|
|
|
|
LuauOpcode getBinaryOpArith(AstExprBinary::Op op, bool k = false)
|
|
{
|
|
switch (op)
|
|
{
|
|
case AstExprBinary::Add:
|
|
return k ? LOP_ADDK : LOP_ADD;
|
|
|
|
case AstExprBinary::Sub:
|
|
return k ? LOP_SUBK : LOP_SUB;
|
|
|
|
case AstExprBinary::Mul:
|
|
return k ? LOP_MULK : LOP_MUL;
|
|
|
|
case AstExprBinary::Div:
|
|
return k ? LOP_DIVK : LOP_DIV;
|
|
|
|
case AstExprBinary::Mod:
|
|
return k ? LOP_MODK : LOP_MOD;
|
|
|
|
case AstExprBinary::Pow:
|
|
return k ? LOP_POWK : LOP_POW;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected binary operation");
|
|
return LOP_NOP;
|
|
}
|
|
}
|
|
|
|
LuauOpcode getJumpOpCompare(AstExprBinary::Op op, bool not_ = false)
|
|
{
|
|
switch (op)
|
|
{
|
|
case AstExprBinary::CompareNe:
|
|
return not_ ? LOP_JUMPIFEQ : LOP_JUMPIFNOTEQ;
|
|
|
|
case AstExprBinary::CompareEq:
|
|
return not_ ? LOP_JUMPIFNOTEQ : LOP_JUMPIFEQ;
|
|
|
|
case AstExprBinary::CompareLt:
|
|
case AstExprBinary::CompareGt:
|
|
return not_ ? LOP_JUMPIFNOTLT : LOP_JUMPIFLT;
|
|
|
|
case AstExprBinary::CompareLe:
|
|
case AstExprBinary::CompareGe:
|
|
return not_ ? LOP_JUMPIFNOTLE : LOP_JUMPIFLE;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected binary operation");
|
|
return LOP_NOP;
|
|
}
|
|
}
|
|
|
|
bool isConstant(AstExpr* node)
|
|
{
|
|
const Constant* cv = constants.find(node);
|
|
|
|
return cv && cv->type != Constant::Type_Unknown;
|
|
}
|
|
|
|
bool isConstantTrue(AstExpr* node)
|
|
{
|
|
const Constant* cv = constants.find(node);
|
|
|
|
return cv && cv->type != Constant::Type_Unknown && cv->isTruthful();
|
|
}
|
|
|
|
bool isConstantFalse(AstExpr* node)
|
|
{
|
|
const Constant* cv = constants.find(node);
|
|
|
|
return cv && cv->type != Constant::Type_Unknown && !cv->isTruthful();
|
|
}
|
|
|
|
size_t compileCompareJump(AstExprBinary* expr, bool not_ = false)
|
|
{
|
|
RegScope rs(this);
|
|
LuauOpcode opc = getJumpOpCompare(expr->op, not_);
|
|
|
|
bool isEq = (opc == LOP_JUMPIFEQ || opc == LOP_JUMPIFNOTEQ);
|
|
AstExpr* left = expr->left;
|
|
AstExpr* right = expr->right;
|
|
|
|
bool operandIsConstant = isConstant(right);
|
|
if (isEq && !operandIsConstant)
|
|
{
|
|
operandIsConstant = isConstant(left);
|
|
if (operandIsConstant)
|
|
std::swap(left, right);
|
|
}
|
|
|
|
uint8_t rl = compileExprAuto(left, rs);
|
|
int32_t rr = -1;
|
|
|
|
if (isEq && operandIsConstant)
|
|
{
|
|
if (opc == LOP_JUMPIFEQ)
|
|
opc = LOP_JUMPIFEQK;
|
|
else if (opc == LOP_JUMPIFNOTEQ)
|
|
opc = LOP_JUMPIFNOTEQK;
|
|
|
|
rr = getConstantIndex(right);
|
|
LUAU_ASSERT(rr >= 0);
|
|
}
|
|
else
|
|
rr = compileExprAuto(right, rs);
|
|
|
|
size_t jumpLabel = bytecode.emitLabel();
|
|
|
|
if (expr->op == AstExprBinary::CompareGt || expr->op == AstExprBinary::CompareGe)
|
|
{
|
|
bytecode.emitAD(opc, uint8_t(rr), 0);
|
|
bytecode.emitAux(rl);
|
|
}
|
|
else
|
|
{
|
|
bytecode.emitAD(opc, rl, 0);
|
|
bytecode.emitAux(rr);
|
|
}
|
|
|
|
return jumpLabel;
|
|
}
|
|
|
|
int32_t getConstantNumber(AstExpr* node)
|
|
{
|
|
const Constant* c = constants.find(node);
|
|
|
|
if (c && c->type == Constant::Type_Number)
|
|
{
|
|
int cid = bytecode.addConstantNumber(c->valueNumber);
|
|
if (cid < 0)
|
|
CompileError::raise(node->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
return cid;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
int32_t getConstantIndex(AstExpr* node)
|
|
{
|
|
const Constant* c = constants.find(node);
|
|
|
|
if (!c || c->type == Constant::Type_Unknown)
|
|
return -1;
|
|
|
|
int cid = -1;
|
|
|
|
switch (c->type)
|
|
{
|
|
case Constant::Type_Nil:
|
|
cid = bytecode.addConstantNil();
|
|
break;
|
|
|
|
case Constant::Type_Boolean:
|
|
cid = bytecode.addConstantBoolean(c->valueBoolean);
|
|
break;
|
|
|
|
case Constant::Type_Number:
|
|
cid = bytecode.addConstantNumber(c->valueNumber);
|
|
break;
|
|
|
|
case Constant::Type_String:
|
|
cid = bytecode.addConstantString(sref(c->getString()));
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected constant type");
|
|
return -1;
|
|
}
|
|
|
|
if (cid < 0)
|
|
CompileError::raise(node->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
return cid;
|
|
}
|
|
|
|
// compile expr to target temp register
|
|
// if the expr (or not expr if onlyTruth is false) is truthy, jump via skipJump
|
|
// if the expr (or not expr if onlyTruth is false) is falsy, fall through (target isn't guaranteed to be updated in this case)
|
|
// if target is omitted, then the jump behavior is the same - skipJump or fallthrough depending on the truthiness of the expression
|
|
void compileConditionValue(AstExpr* node, const uint8_t* target, std::vector<size_t>& skipJump, bool onlyTruth)
|
|
{
|
|
// Optimization: we don't need to compute constant values
|
|
const Constant* cv = constants.find(node);
|
|
|
|
if (cv && cv->type != Constant::Type_Unknown)
|
|
{
|
|
// note that we only need to compute the value if it's truthy; otherwise we cal fall through
|
|
if (cv->isTruthful() == onlyTruth)
|
|
{
|
|
if (target)
|
|
compileExprTemp(node, *target);
|
|
|
|
skipJump.push_back(bytecode.emitLabel());
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (AstExprBinary* expr = node->as<AstExprBinary>())
|
|
{
|
|
switch (expr->op)
|
|
{
|
|
case AstExprBinary::And:
|
|
case AstExprBinary::Or:
|
|
{
|
|
// disambiguation: there's 4 cases (we only need truthy or falsy results based on onlyTruth)
|
|
// onlyTruth = 1: a and b transforms to a ? b : dontcare
|
|
// onlyTruth = 1: a or b transforms to a ? a : a
|
|
// onlyTruth = 0: a and b transforms to !a ? a : b
|
|
// onlyTruth = 0: a or b transforms to !a ? b : dontcare
|
|
if (onlyTruth == (expr->op == AstExprBinary::And))
|
|
{
|
|
// we need to compile the left hand side, and skip to "dontcare" (aka fallthrough of the entire statement) if it's not the same as
|
|
// onlyTruth if it's the same then the result of the expression is the right hand side because of this, we *never* care about the
|
|
// result of the left hand side
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(expr->left, nullptr, elseJump, !onlyTruth);
|
|
|
|
// fallthrough indicates that we need to compute & return the right hand side
|
|
// we use compileConditionValue again to process any extra and/or statements directly
|
|
compileConditionValue(expr->right, target, skipJump, onlyTruth);
|
|
|
|
size_t elseLabel = bytecode.emitLabel();
|
|
|
|
patchJumps(expr, elseJump, elseLabel);
|
|
}
|
|
else
|
|
{
|
|
// we need to compute the left hand side first; note that we will jump to skipJump if we know the answer
|
|
compileConditionValue(expr->left, target, skipJump, onlyTruth);
|
|
|
|
// we will fall through if computing the left hand didn't give us an "interesting" result
|
|
// we still use compileConditionValue to recursively optimize any and/or/compare statements
|
|
compileConditionValue(expr->right, target, skipJump, onlyTruth);
|
|
}
|
|
return;
|
|
}
|
|
break;
|
|
|
|
case AstExprBinary::CompareNe:
|
|
case AstExprBinary::CompareEq:
|
|
case AstExprBinary::CompareLt:
|
|
case AstExprBinary::CompareLe:
|
|
case AstExprBinary::CompareGt:
|
|
case AstExprBinary::CompareGe:
|
|
{
|
|
if (target)
|
|
{
|
|
// since target is a temp register, we'll initialize it to 1, and then jump if the comparison is true
|
|
// if the comparison is false, we'll fallthrough and target will still be 1 but target has unspecified value for falsy results
|
|
// when we only care about falsy values instead of truthy values, the process is the same but with flipped conditionals
|
|
bytecode.emitABC(LOP_LOADB, *target, onlyTruth ? 1 : 0, 0);
|
|
}
|
|
|
|
size_t jumpLabel = compileCompareJump(expr, /* not= */ !onlyTruth);
|
|
|
|
skipJump.push_back(jumpLabel);
|
|
return;
|
|
}
|
|
break;
|
|
|
|
// fall-through to default path below
|
|
default:;
|
|
}
|
|
}
|
|
|
|
if (AstExprUnary* expr = node->as<AstExprUnary>())
|
|
{
|
|
// if we *do* need to compute the target, we'd have to inject "not" ops on every return path
|
|
// this is possible but cumbersome; so for now we only optimize not expression when we *don't* need the value
|
|
if (!target && expr->op == AstExprUnary::Not)
|
|
{
|
|
compileConditionValue(expr->expr, target, skipJump, !onlyTruth);
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (AstExprGroup* expr = node->as<AstExprGroup>())
|
|
{
|
|
compileConditionValue(expr->expr, target, skipJump, onlyTruth);
|
|
return;
|
|
}
|
|
|
|
RegScope rs(this);
|
|
uint8_t reg;
|
|
|
|
if (target)
|
|
{
|
|
reg = *target;
|
|
compileExprTemp(node, reg);
|
|
}
|
|
else
|
|
{
|
|
reg = compileExprAuto(node, rs);
|
|
}
|
|
|
|
skipJump.push_back(bytecode.emitLabel());
|
|
bytecode.emitAD(onlyTruth ? LOP_JUMPIF : LOP_JUMPIFNOT, reg, 0);
|
|
}
|
|
|
|
// checks if compiling the expression as a condition value generates code that's faster than using compileExpr
|
|
bool isConditionFast(AstExpr* node)
|
|
{
|
|
const Constant* cv = constants.find(node);
|
|
|
|
if (cv && cv->type != Constant::Type_Unknown)
|
|
return true;
|
|
|
|
if (AstExprBinary* expr = node->as<AstExprBinary>())
|
|
{
|
|
switch (expr->op)
|
|
{
|
|
case AstExprBinary::And:
|
|
case AstExprBinary::Or:
|
|
return true;
|
|
|
|
case AstExprBinary::CompareNe:
|
|
case AstExprBinary::CompareEq:
|
|
case AstExprBinary::CompareLt:
|
|
case AstExprBinary::CompareLe:
|
|
case AstExprBinary::CompareGt:
|
|
case AstExprBinary::CompareGe:
|
|
return true;
|
|
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (AstExprGroup* expr = node->as<AstExprGroup>())
|
|
return isConditionFast(expr->expr);
|
|
|
|
return false;
|
|
}
|
|
|
|
void compileExprAndOr(AstExprBinary* expr, uint8_t target, bool targetTemp)
|
|
{
|
|
bool and_ = (expr->op == AstExprBinary::And);
|
|
|
|
RegScope rs(this);
|
|
|
|
// Optimization: when left hand side is a constant, we can emit left hand side or right hand side
|
|
const Constant* cl = constants.find(expr->left);
|
|
|
|
if (cl && cl->type != Constant::Type_Unknown)
|
|
{
|
|
compileExpr(and_ == cl->isTruthful() ? expr->right : expr->left, target, targetTemp);
|
|
return;
|
|
}
|
|
|
|
// Note: two optimizations below can lead to inefficient codegen when the left hand side is a condition
|
|
if (!isConditionFast(expr->left))
|
|
{
|
|
// Optimization: when right hand side is a local variable, we can use AND/OR
|
|
if (isExprLocalReg(expr->right))
|
|
{
|
|
uint8_t lr = compileExprAuto(expr->left, rs);
|
|
uint8_t rr = getLocal(expr->right->as<AstExprLocal>()->local);
|
|
|
|
bytecode.emitABC(and_ ? LOP_AND : LOP_OR, target, lr, rr);
|
|
return;
|
|
}
|
|
|
|
// Optimization: when right hand side is a constant, we can use ANDK/ORK
|
|
int32_t cid = getConstantIndex(expr->right);
|
|
|
|
if (cid >= 0 && cid <= 255)
|
|
{
|
|
uint8_t lr = compileExprAuto(expr->left, rs);
|
|
|
|
bytecode.emitABC(and_ ? LOP_ANDK : LOP_ORK, target, lr, uint8_t(cid));
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Optimization: if target is a temp register, we can clobber it which allows us to compute the result directly into it
|
|
// If it's not a temp register, then something like `a = a > 1 or a + 2` may clobber `a` while evaluating left hand side, and `a+2` will break
|
|
uint8_t reg = targetTemp ? target : allocReg(expr, 1);
|
|
|
|
std::vector<size_t> skipJump;
|
|
compileConditionValue(expr->left, ®, skipJump, /* onlyTruth= */ !and_);
|
|
|
|
compileExprTemp(expr->right, reg);
|
|
|
|
size_t moveLabel = bytecode.emitLabel();
|
|
|
|
patchJumps(expr, skipJump, moveLabel);
|
|
|
|
if (target != reg)
|
|
bytecode.emitABC(LOP_MOVE, target, reg, 0);
|
|
}
|
|
|
|
void compileExprUnary(AstExprUnary* expr, uint8_t target)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
uint8_t re = compileExprAuto(expr->expr, rs);
|
|
|
|
bytecode.emitABC(getUnaryOp(expr->op), target, re, 0);
|
|
}
|
|
|
|
static void unrollConcats(std::vector<AstExpr*>& args)
|
|
{
|
|
for (;;)
|
|
{
|
|
AstExprBinary* be = args.back()->as<AstExprBinary>();
|
|
|
|
if (!be || be->op != AstExprBinary::Concat)
|
|
break;
|
|
|
|
args.back() = be->left;
|
|
args.push_back(be->right);
|
|
}
|
|
}
|
|
|
|
void compileExprBinary(AstExprBinary* expr, uint8_t target, bool targetTemp)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
switch (expr->op)
|
|
{
|
|
case AstExprBinary::Add:
|
|
case AstExprBinary::Sub:
|
|
case AstExprBinary::Mul:
|
|
case AstExprBinary::Div:
|
|
case AstExprBinary::Mod:
|
|
case AstExprBinary::Pow:
|
|
{
|
|
int32_t rc = getConstantNumber(expr->right);
|
|
|
|
if (rc >= 0 && rc <= 255)
|
|
{
|
|
uint8_t rl = compileExprAuto(expr->left, rs);
|
|
|
|
bytecode.emitABC(getBinaryOpArith(expr->op, /* k= */ true), target, rl, uint8_t(rc));
|
|
}
|
|
else
|
|
{
|
|
uint8_t rl = compileExprAuto(expr->left, rs);
|
|
uint8_t rr = compileExprAuto(expr->right, rs);
|
|
|
|
bytecode.emitABC(getBinaryOpArith(expr->op), target, rl, rr);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case AstExprBinary::Concat:
|
|
{
|
|
std::vector<AstExpr*> args = {expr->left, expr->right};
|
|
|
|
// unroll the tree of concats down the right hand side to be able to do multiple ops
|
|
unrollConcats(args);
|
|
|
|
uint8_t regs = allocReg(expr, unsigned(args.size()));
|
|
|
|
for (size_t i = 0; i < args.size(); ++i)
|
|
compileExprTemp(args[i], uint8_t(regs + i));
|
|
|
|
bytecode.emitABC(LOP_CONCAT, target, regs, uint8_t(regs + args.size() - 1));
|
|
}
|
|
break;
|
|
|
|
case AstExprBinary::CompareNe:
|
|
case AstExprBinary::CompareEq:
|
|
case AstExprBinary::CompareLt:
|
|
case AstExprBinary::CompareLe:
|
|
case AstExprBinary::CompareGt:
|
|
case AstExprBinary::CompareGe:
|
|
{
|
|
size_t jumpLabel = compileCompareJump(expr);
|
|
|
|
// note: this skips over the next LOADB instruction because of "1" in the C slot
|
|
bytecode.emitABC(LOP_LOADB, target, 0, 1);
|
|
|
|
size_t thenLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitABC(LOP_LOADB, target, 1, 0);
|
|
|
|
patchJump(expr, jumpLabel, thenLabel);
|
|
}
|
|
break;
|
|
|
|
case AstExprBinary::And:
|
|
case AstExprBinary::Or:
|
|
{
|
|
compileExprAndOr(expr, target, targetTemp);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected binary operation");
|
|
}
|
|
}
|
|
|
|
void compileExprIfElse(AstExprIfElse* expr, uint8_t target, bool targetTemp)
|
|
{
|
|
if (isConstant(expr->condition))
|
|
{
|
|
if (isConstantTrue(expr->condition))
|
|
{
|
|
compileExpr(expr->trueExpr, target, targetTemp);
|
|
}
|
|
else
|
|
{
|
|
compileExpr(expr->falseExpr, target, targetTemp);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(expr->condition, nullptr, elseJump, false);
|
|
compileExpr(expr->trueExpr, target, targetTemp);
|
|
|
|
// Jump over else expression evaluation
|
|
size_t thenLabel = bytecode.emitLabel();
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
|
|
size_t elseLabel = bytecode.emitLabel();
|
|
compileExpr(expr->falseExpr, target, targetTemp);
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJumps(expr, elseJump, elseLabel);
|
|
patchJump(expr, thenLabel, endLabel);
|
|
}
|
|
}
|
|
|
|
static uint8_t encodeHashSize(unsigned int hashSize)
|
|
{
|
|
size_t hashSizeLog2 = 0;
|
|
while ((1u << hashSizeLog2) < hashSize)
|
|
hashSizeLog2++;
|
|
|
|
return hashSize == 0 ? 0 : uint8_t(hashSizeLog2 + 1);
|
|
}
|
|
|
|
void compileExprTable(AstExprTable* expr, uint8_t target, bool targetTemp)
|
|
{
|
|
// Optimization: if the table is empty, we can compute it directly into the target
|
|
if (expr->items.size == 0)
|
|
{
|
|
TableShape shape = tableShapes[expr];
|
|
|
|
bytecode.emitABC(LOP_NEWTABLE, target, encodeHashSize(shape.hashSize), 0);
|
|
bytecode.emitAux(shape.arraySize);
|
|
return;
|
|
}
|
|
|
|
unsigned int arraySize = 0;
|
|
unsigned int hashSize = 0;
|
|
unsigned int recordSize = 0;
|
|
unsigned int indexSize = 0;
|
|
|
|
for (size_t i = 0; i < expr->items.size; ++i)
|
|
{
|
|
const AstExprTable::Item& item = expr->items.data[i];
|
|
|
|
arraySize += (item.kind == AstExprTable::Item::List);
|
|
hashSize += (item.kind != AstExprTable::Item::List);
|
|
recordSize += (item.kind == AstExprTable::Item::Record);
|
|
}
|
|
|
|
// Optimization: allocate sequential explicitly specified numeric indices ([1]) as arrays
|
|
if (arraySize == 0 && hashSize > 0)
|
|
{
|
|
for (size_t i = 0; i < expr->items.size; ++i)
|
|
{
|
|
const AstExprTable::Item& item = expr->items.data[i];
|
|
LUAU_ASSERT(item.key); // no list portion => all items have keys
|
|
|
|
const Constant* ckey = constants.find(item.key);
|
|
|
|
indexSize += (ckey && ckey->type == Constant::Type_Number && ckey->valueNumber == double(indexSize + 1));
|
|
}
|
|
|
|
// we only perform the optimization if we don't have any other []-keys
|
|
// technically it's "safe" to do this even if we have other keys, but doing so changes iteration order and may break existing code
|
|
if (hashSize == recordSize + indexSize)
|
|
hashSize = recordSize;
|
|
else
|
|
indexSize = 0;
|
|
}
|
|
|
|
int encodedHashSize = encodeHashSize(hashSize);
|
|
|
|
RegScope rs(this);
|
|
|
|
// Optimization: if target is a temp register, we can clobber it which allows us to compute the result directly into it
|
|
uint8_t reg = targetTemp ? target : allocReg(expr, 1);
|
|
|
|
// Optimization: when all items are record fields, use template tables to compile expression
|
|
if (arraySize == 0 && indexSize == 0 && hashSize == recordSize && recordSize >= 1 && recordSize <= BytecodeBuilder::TableShape::kMaxLength)
|
|
{
|
|
BytecodeBuilder::TableShape shape;
|
|
|
|
for (size_t i = 0; i < expr->items.size; ++i)
|
|
{
|
|
const AstExprTable::Item& item = expr->items.data[i];
|
|
LUAU_ASSERT(item.kind == AstExprTable::Item::Record);
|
|
|
|
AstExprConstantString* ckey = item.key->as<AstExprConstantString>();
|
|
LUAU_ASSERT(ckey);
|
|
|
|
int cid = bytecode.addConstantString(sref(ckey->value));
|
|
if (cid < 0)
|
|
CompileError::raise(ckey->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
LUAU_ASSERT(shape.length < BytecodeBuilder::TableShape::kMaxLength);
|
|
shape.keys[shape.length++] = int16_t(cid);
|
|
}
|
|
|
|
int32_t tid = bytecode.addConstantTable(shape);
|
|
if (tid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
if (tid < 32768)
|
|
{
|
|
bytecode.emitAD(LOP_DUPTABLE, reg, int16_t(tid));
|
|
}
|
|
else
|
|
{
|
|
bytecode.emitABC(LOP_NEWTABLE, reg, uint8_t(encodedHashSize), 0);
|
|
bytecode.emitAux(0);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// Optimization: instead of allocating one extra element when the last element of the table literal is ..., let SETLIST allocate the
|
|
// correct amount of storage
|
|
const AstExprTable::Item* last = expr->items.size > 0 ? &expr->items.data[expr->items.size - 1] : nullptr;
|
|
|
|
bool trailingVarargs = last && last->kind == AstExprTable::Item::List && last->value->is<AstExprVarargs>();
|
|
LUAU_ASSERT(!trailingVarargs || arraySize > 0);
|
|
|
|
bytecode.emitABC(LOP_NEWTABLE, reg, uint8_t(encodedHashSize), 0);
|
|
bytecode.emitAux(arraySize - trailingVarargs + indexSize);
|
|
}
|
|
|
|
unsigned int arrayChunkSize = std::min(16u, arraySize);
|
|
uint8_t arrayChunkReg = allocReg(expr, arrayChunkSize);
|
|
unsigned int arrayChunkCurrent = 0;
|
|
|
|
unsigned int arrayIndex = 1;
|
|
bool multRet = false;
|
|
|
|
for (size_t i = 0; i < expr->items.size; ++i)
|
|
{
|
|
const AstExprTable::Item& item = expr->items.data[i];
|
|
|
|
AstExpr* key = item.key;
|
|
AstExpr* value = item.value;
|
|
|
|
// some key/value pairs don't require us to compile the expressions, so we need to setup the line info here
|
|
setDebugLine(value);
|
|
|
|
if (options.coverageLevel >= 2)
|
|
{
|
|
bytecode.emitABC(LOP_COVERAGE, 0, 0, 0);
|
|
}
|
|
|
|
// flush array chunk on overflow or before hash keys to maintain insertion order
|
|
if (arrayChunkCurrent > 0 && (key || arrayChunkCurrent == arrayChunkSize))
|
|
{
|
|
bytecode.emitABC(LOP_SETLIST, reg, arrayChunkReg, uint8_t(arrayChunkCurrent + 1));
|
|
bytecode.emitAux(arrayIndex);
|
|
arrayIndex += arrayChunkCurrent;
|
|
arrayChunkCurrent = 0;
|
|
}
|
|
|
|
// items with a key are set one by one via SETTABLE/SETTABLEKS/SETTABLEN
|
|
if (key)
|
|
{
|
|
RegScope rsi(this);
|
|
|
|
LValue lv = compileLValueIndex(reg, key, rsi);
|
|
uint8_t rv = compileExprAuto(value, rsi);
|
|
|
|
compileAssign(lv, rv);
|
|
}
|
|
// items without a key are set using SETLIST so that we can initialize large arrays quickly
|
|
else
|
|
{
|
|
uint8_t temp = uint8_t(arrayChunkReg + arrayChunkCurrent);
|
|
|
|
if (i + 1 == expr->items.size)
|
|
multRet = compileExprTempMultRet(value, temp);
|
|
else
|
|
compileExprTempTop(value, temp);
|
|
|
|
arrayChunkCurrent++;
|
|
}
|
|
}
|
|
|
|
// flush last array chunk; note that this needs multret handling if the last expression was multret
|
|
if (arrayChunkCurrent)
|
|
{
|
|
bytecode.emitABC(LOP_SETLIST, reg, arrayChunkReg, multRet ? 0 : uint8_t(arrayChunkCurrent + 1));
|
|
bytecode.emitAux(arrayIndex);
|
|
}
|
|
|
|
if (target != reg)
|
|
bytecode.emitABC(LOP_MOVE, target, reg, 0);
|
|
}
|
|
|
|
bool canImport(AstExprGlobal* expr)
|
|
{
|
|
return options.optimizationLevel >= 1 && getGlobalState(globals, expr->name) != Global::Written;
|
|
}
|
|
|
|
bool canImportChain(AstExprGlobal* expr)
|
|
{
|
|
return options.optimizationLevel >= 1 && getGlobalState(globals, expr->name) == Global::Default;
|
|
}
|
|
|
|
void compileExprIndexName(AstExprIndexName* expr, uint8_t target)
|
|
{
|
|
setDebugLine(expr); // normally compileExpr sets up line info, but compileExprIndexName can be called directly
|
|
|
|
// Optimization: index chains that start from global variables can be compiled into GETIMPORT statement
|
|
AstExprGlobal* importRoot = 0;
|
|
AstExprIndexName* import1 = 0;
|
|
AstExprIndexName* import2 = 0;
|
|
|
|
if (AstExprIndexName* index = expr->expr->as<AstExprIndexName>())
|
|
{
|
|
importRoot = index->expr->as<AstExprGlobal>();
|
|
import1 = index;
|
|
import2 = expr;
|
|
}
|
|
else
|
|
{
|
|
importRoot = expr->expr->as<AstExprGlobal>();
|
|
import1 = expr;
|
|
}
|
|
|
|
if (importRoot && canImportChain(importRoot))
|
|
{
|
|
int32_t id0 = bytecode.addConstantString(sref(importRoot->name));
|
|
int32_t id1 = bytecode.addConstantString(sref(import1->index));
|
|
int32_t id2 = import2 ? bytecode.addConstantString(sref(import2->index)) : -1;
|
|
|
|
if (id0 < 0 || id1 < 0 || (import2 && id2 < 0))
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
// Note: GETIMPORT encoding is limited to 10 bits per object id component
|
|
if (id0 < 1024 && id1 < 1024 && id2 < 1024)
|
|
{
|
|
uint32_t iid = import2 ? BytecodeBuilder::getImportId(id0, id1, id2) : BytecodeBuilder::getImportId(id0, id1);
|
|
int32_t cid = bytecode.addImport(iid);
|
|
|
|
if (cid >= 0 && cid < 32768)
|
|
{
|
|
bytecode.emitAD(LOP_GETIMPORT, target, int16_t(cid));
|
|
bytecode.emitAux(iid);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
RegScope rs(this);
|
|
uint8_t reg = compileExprAuto(expr->expr, rs);
|
|
|
|
setDebugLine(expr->indexLocation);
|
|
|
|
BytecodeBuilder::StringRef iname = sref(expr->index);
|
|
int32_t cid = bytecode.addConstantString(iname);
|
|
if (cid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
bytecode.emitABC(LOP_GETTABLEKS, target, reg, uint8_t(BytecodeBuilder::getStringHash(iname)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
|
|
void compileExprIndexExpr(AstExprIndexExpr* expr, uint8_t target)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
// note: cv may be invalidated by compileExpr* so we stop using it before calling compile recursively
|
|
const Constant* cv = constants.find(expr->index);
|
|
|
|
if (cv && cv->type == Constant::Type_Number && cv->valueNumber >= 1 && cv->valueNumber <= 256 &&
|
|
double(int(cv->valueNumber)) == cv->valueNumber)
|
|
{
|
|
uint8_t i = uint8_t(int(cv->valueNumber) - 1);
|
|
|
|
uint8_t rt = compileExprAuto(expr->expr, rs);
|
|
|
|
setDebugLine(expr->index);
|
|
|
|
bytecode.emitABC(LOP_GETTABLEN, target, rt, i);
|
|
}
|
|
else if (cv && cv->type == Constant::Type_String)
|
|
{
|
|
BytecodeBuilder::StringRef iname = sref(cv->getString());
|
|
int32_t cid = bytecode.addConstantString(iname);
|
|
if (cid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
uint8_t rt = compileExprAuto(expr->expr, rs);
|
|
|
|
setDebugLine(expr->index);
|
|
|
|
bytecode.emitABC(LOP_GETTABLEKS, target, rt, uint8_t(BytecodeBuilder::getStringHash(iname)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
else
|
|
{
|
|
uint8_t rt = compileExprAuto(expr->expr, rs);
|
|
uint8_t ri = compileExprAuto(expr->index, rs);
|
|
|
|
bytecode.emitABC(LOP_GETTABLE, target, rt, ri);
|
|
}
|
|
}
|
|
|
|
void compileExprGlobal(AstExprGlobal* expr, uint8_t target)
|
|
{
|
|
// Optimization: builtin globals can be retrieved using GETIMPORT
|
|
if (canImport(expr))
|
|
{
|
|
int32_t id0 = bytecode.addConstantString(sref(expr->name));
|
|
if (id0 < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
// Note: GETIMPORT encoding is limited to 10 bits per object id component
|
|
if (id0 < 1024)
|
|
{
|
|
uint32_t iid = BytecodeBuilder::getImportId(id0);
|
|
int32_t cid = bytecode.addImport(iid);
|
|
|
|
if (cid >= 0 && cid < 32768)
|
|
{
|
|
bytecode.emitAD(LOP_GETIMPORT, target, int16_t(cid));
|
|
bytecode.emitAux(iid);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
BytecodeBuilder::StringRef gname = sref(expr->name);
|
|
int32_t cid = bytecode.addConstantString(gname);
|
|
if (cid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
bytecode.emitABC(LOP_GETGLOBAL, target, 0, uint8_t(BytecodeBuilder::getStringHash(gname)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
|
|
void compileExprConstant(AstExpr* node, const Constant* cv, uint8_t target)
|
|
{
|
|
switch (cv->type)
|
|
{
|
|
case Constant::Type_Nil:
|
|
bytecode.emitABC(LOP_LOADNIL, target, 0, 0);
|
|
break;
|
|
|
|
case Constant::Type_Boolean:
|
|
bytecode.emitABC(LOP_LOADB, target, cv->valueBoolean, 0);
|
|
break;
|
|
|
|
case Constant::Type_Number:
|
|
{
|
|
double d = cv->valueNumber;
|
|
|
|
if (d >= std::numeric_limits<int16_t>::min() && d <= std::numeric_limits<int16_t>::max() && double(int16_t(d)) == d &&
|
|
!(d == 0.0 && signbit(d)))
|
|
{
|
|
// short number encoding: doesn't require a table entry lookup
|
|
bytecode.emitAD(LOP_LOADN, target, int16_t(d));
|
|
}
|
|
else
|
|
{
|
|
// long number encoding: use generic constant path
|
|
int32_t cid = bytecode.addConstantNumber(d);
|
|
if (cid < 0)
|
|
CompileError::raise(node->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
emitLoadK(target, cid);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case Constant::Type_String:
|
|
{
|
|
int32_t cid = bytecode.addConstantString(sref(cv->getString()));
|
|
if (cid < 0)
|
|
CompileError::raise(node->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
emitLoadK(target, cid);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected constant type");
|
|
}
|
|
}
|
|
|
|
void compileExpr(AstExpr* node, uint8_t target, bool targetTemp = false)
|
|
{
|
|
setDebugLine(node);
|
|
|
|
if (options.coverageLevel >= 2 && needsCoverage(node))
|
|
{
|
|
bytecode.emitABC(LOP_COVERAGE, 0, 0, 0);
|
|
}
|
|
|
|
// Optimization: if expression has a constant value, we can emit it directly
|
|
if (const Constant* cv = constants.find(node))
|
|
{
|
|
if (cv->type != Constant::Type_Unknown)
|
|
{
|
|
compileExprConstant(node, cv, target);
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (AstExprGroup* expr = node->as<AstExprGroup>())
|
|
{
|
|
compileExpr(expr->expr, target, targetTemp);
|
|
}
|
|
else if (node->is<AstExprConstantNil>())
|
|
{
|
|
bytecode.emitABC(LOP_LOADNIL, target, 0, 0);
|
|
}
|
|
else if (AstExprConstantBool* expr = node->as<AstExprConstantBool>())
|
|
{
|
|
bytecode.emitABC(LOP_LOADB, target, expr->value, 0);
|
|
}
|
|
else if (AstExprConstantNumber* expr = node->as<AstExprConstantNumber>())
|
|
{
|
|
int32_t cid = bytecode.addConstantNumber(expr->value);
|
|
if (cid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
emitLoadK(target, cid);
|
|
}
|
|
else if (AstExprConstantString* expr = node->as<AstExprConstantString>())
|
|
{
|
|
int32_t cid = bytecode.addConstantString(sref(expr->value));
|
|
if (cid < 0)
|
|
CompileError::raise(expr->location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
emitLoadK(target, cid);
|
|
}
|
|
else if (AstExprLocal* expr = node->as<AstExprLocal>())
|
|
{
|
|
if (FFlag::LuauCompileSupportInlining ? !isExprLocalReg(expr) : expr->upvalue)
|
|
{
|
|
LUAU_ASSERT(expr->upvalue);
|
|
uint8_t uid = getUpval(expr->local);
|
|
|
|
bytecode.emitABC(LOP_GETUPVAL, target, uid, 0);
|
|
}
|
|
else
|
|
{
|
|
uint8_t reg = getLocal(expr->local);
|
|
|
|
bytecode.emitABC(LOP_MOVE, target, reg, 0);
|
|
}
|
|
}
|
|
else if (AstExprGlobal* expr = node->as<AstExprGlobal>())
|
|
{
|
|
compileExprGlobal(expr, target);
|
|
}
|
|
else if (AstExprVarargs* expr = node->as<AstExprVarargs>())
|
|
{
|
|
compileExprVarargs(expr, target, /* targetCount= */ 1);
|
|
}
|
|
else if (AstExprCall* expr = node->as<AstExprCall>())
|
|
{
|
|
// Optimization: when targeting temporary registers, we can compile call in a special mode that doesn't require extra register moves
|
|
if (targetTemp && target == regTop - 1)
|
|
compileExprCall(expr, target, 1, /* targetTop= */ true);
|
|
else
|
|
compileExprCall(expr, target, /* targetCount= */ 1);
|
|
}
|
|
else if (AstExprIndexName* expr = node->as<AstExprIndexName>())
|
|
{
|
|
compileExprIndexName(expr, target);
|
|
}
|
|
else if (AstExprIndexExpr* expr = node->as<AstExprIndexExpr>())
|
|
{
|
|
compileExprIndexExpr(expr, target);
|
|
}
|
|
else if (AstExprFunction* expr = node->as<AstExprFunction>())
|
|
{
|
|
compileExprFunction(expr, target);
|
|
}
|
|
else if (AstExprTable* expr = node->as<AstExprTable>())
|
|
{
|
|
compileExprTable(expr, target, targetTemp);
|
|
}
|
|
else if (AstExprUnary* expr = node->as<AstExprUnary>())
|
|
{
|
|
compileExprUnary(expr, target);
|
|
}
|
|
else if (AstExprBinary* expr = node->as<AstExprBinary>())
|
|
{
|
|
compileExprBinary(expr, target, targetTemp);
|
|
}
|
|
else if (AstExprTypeAssertion* expr = node->as<AstExprTypeAssertion>())
|
|
{
|
|
compileExpr(expr->expr, target, targetTemp);
|
|
}
|
|
else if (AstExprIfElse* expr = node->as<AstExprIfElse>())
|
|
{
|
|
compileExprIfElse(expr, target, targetTemp);
|
|
}
|
|
else
|
|
{
|
|
LUAU_ASSERT(!"Unknown expression type");
|
|
}
|
|
}
|
|
|
|
void compileExprTemp(AstExpr* node, uint8_t target)
|
|
{
|
|
return compileExpr(node, target, /* targetTemp= */ true);
|
|
}
|
|
|
|
uint8_t compileExprAuto(AstExpr* node, RegScope&)
|
|
{
|
|
// Optimization: directly return locals instead of copying them to a temporary
|
|
if (isExprLocalReg(node))
|
|
return getLocal(node->as<AstExprLocal>()->local);
|
|
|
|
// note: the register is owned by the parent scope
|
|
uint8_t reg = allocReg(node, 1);
|
|
|
|
compileExprTemp(node, reg);
|
|
|
|
return reg;
|
|
}
|
|
|
|
// initializes target..target+targetCount-1 range using expressions from the list
|
|
// if list has fewer expressions, and last expression is a call, we assume the call returns the rest of the values
|
|
// if list has fewer expressions, and last expression isn't a call, we fill the rest with nil
|
|
// assumes target register range can be clobbered and is at the top of the register space if targetTop = true
|
|
void compileExprListTemp(const AstArray<AstExpr*>& list, uint8_t target, uint8_t targetCount, bool targetTop)
|
|
{
|
|
// we assume that target range is at the top of the register space and can be clobbered
|
|
// this is what allows us to compile the last call expression - if it's a call - using targetTop=true
|
|
LUAU_ASSERT(!targetTop || unsigned(target + targetCount) == regTop);
|
|
|
|
if (list.size == targetCount)
|
|
{
|
|
for (size_t i = 0; i < list.size; ++i)
|
|
compileExprTemp(list.data[i], uint8_t(target + i));
|
|
}
|
|
else if (list.size > targetCount)
|
|
{
|
|
for (size_t i = 0; i < targetCount; ++i)
|
|
compileExprTemp(list.data[i], uint8_t(target + i));
|
|
|
|
// compute expressions with values that go nowhere; this is required to run side-effecting code if any
|
|
for (size_t i = targetCount; i < list.size; ++i)
|
|
{
|
|
RegScope rsi(this);
|
|
compileExprAuto(list.data[i], rsi);
|
|
}
|
|
}
|
|
else if (list.size > 0)
|
|
{
|
|
for (size_t i = 0; i < list.size - 1; ++i)
|
|
compileExprTemp(list.data[i], uint8_t(target + i));
|
|
|
|
AstExpr* last = list.data[list.size - 1];
|
|
|
|
if (AstExprCall* expr = last->as<AstExprCall>())
|
|
{
|
|
compileExprCall(expr, uint8_t(target + list.size - 1), uint8_t(targetCount - (list.size - 1)), targetTop);
|
|
}
|
|
else if (AstExprVarargs* expr = last->as<AstExprVarargs>())
|
|
{
|
|
compileExprVarargs(expr, uint8_t(target + list.size - 1), uint8_t(targetCount - (list.size - 1)));
|
|
}
|
|
else
|
|
{
|
|
compileExprTemp(last, uint8_t(target + list.size - 1));
|
|
|
|
for (size_t i = list.size; i < targetCount; ++i)
|
|
bytecode.emitABC(LOP_LOADNIL, uint8_t(target + i), 0, 0);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for (size_t i = 0; i < targetCount; ++i)
|
|
bytecode.emitABC(LOP_LOADNIL, uint8_t(target + i), 0, 0);
|
|
}
|
|
}
|
|
|
|
struct LValue
|
|
{
|
|
enum Kind
|
|
{
|
|
Kind_Local,
|
|
Kind_Upvalue,
|
|
Kind_Global,
|
|
Kind_IndexName,
|
|
Kind_IndexNumber,
|
|
Kind_IndexExpr,
|
|
};
|
|
|
|
Kind kind;
|
|
uint8_t reg; // register for local (Local) or table (Index*)
|
|
uint8_t upval;
|
|
uint8_t index; // register for index in IndexExpr
|
|
uint8_t number; // index-1 (0-255) in IndexNumber
|
|
BytecodeBuilder::StringRef name;
|
|
Location location;
|
|
};
|
|
|
|
LValue compileLValueIndex(uint8_t reg, AstExpr* index, RegScope& rs)
|
|
{
|
|
const Constant* cv = constants.find(index);
|
|
|
|
if (cv && cv->type == Constant::Type_Number && cv->valueNumber >= 1 && cv->valueNumber <= 256 &&
|
|
double(int(cv->valueNumber)) == cv->valueNumber)
|
|
{
|
|
LValue result = {LValue::Kind_IndexNumber};
|
|
result.reg = reg;
|
|
result.number = uint8_t(int(cv->valueNumber) - 1);
|
|
result.location = index->location;
|
|
|
|
return result;
|
|
}
|
|
else if (cv && cv->type == Constant::Type_String)
|
|
{
|
|
LValue result = {LValue::Kind_IndexName};
|
|
result.reg = reg;
|
|
result.name = sref(cv->getString());
|
|
result.location = index->location;
|
|
|
|
return result;
|
|
}
|
|
else
|
|
{
|
|
LValue result = {LValue::Kind_IndexExpr};
|
|
result.reg = reg;
|
|
result.index = compileExprAuto(index, rs);
|
|
result.location = index->location;
|
|
|
|
return result;
|
|
}
|
|
}
|
|
|
|
LValue compileLValue(AstExpr* node, RegScope& rs)
|
|
{
|
|
setDebugLine(node);
|
|
|
|
if (AstExprLocal* expr = node->as<AstExprLocal>())
|
|
{
|
|
if (FFlag::LuauCompileSupportInlining ? !isExprLocalReg(expr) : expr->upvalue)
|
|
{
|
|
LUAU_ASSERT(expr->upvalue);
|
|
|
|
LValue result = {LValue::Kind_Upvalue};
|
|
result.upval = getUpval(expr->local);
|
|
result.location = node->location;
|
|
|
|
return result;
|
|
}
|
|
else
|
|
{
|
|
LValue result = {LValue::Kind_Local};
|
|
result.reg = getLocal(expr->local);
|
|
result.location = node->location;
|
|
|
|
return result;
|
|
}
|
|
}
|
|
else if (AstExprGlobal* expr = node->as<AstExprGlobal>())
|
|
{
|
|
LValue result = {LValue::Kind_Global};
|
|
result.name = sref(expr->name);
|
|
result.location = node->location;
|
|
|
|
return result;
|
|
}
|
|
else if (AstExprIndexName* expr = node->as<AstExprIndexName>())
|
|
{
|
|
LValue result = {LValue::Kind_IndexName};
|
|
result.reg = compileExprAuto(expr->expr, rs);
|
|
result.name = sref(expr->index);
|
|
result.location = node->location;
|
|
|
|
return result;
|
|
}
|
|
else if (AstExprIndexExpr* expr = node->as<AstExprIndexExpr>())
|
|
{
|
|
uint8_t reg = compileExprAuto(expr->expr, rs);
|
|
|
|
return compileLValueIndex(reg, expr->index, rs);
|
|
}
|
|
else
|
|
{
|
|
LUAU_ASSERT(!"Unknown assignment expression");
|
|
|
|
return LValue();
|
|
}
|
|
}
|
|
|
|
void compileLValueUse(const LValue& lv, uint8_t reg, bool set)
|
|
{
|
|
setDebugLine(lv.location);
|
|
|
|
switch (lv.kind)
|
|
{
|
|
case LValue::Kind_Local:
|
|
if (set)
|
|
bytecode.emitABC(LOP_MOVE, lv.reg, reg, 0);
|
|
else
|
|
bytecode.emitABC(LOP_MOVE, reg, lv.reg, 0);
|
|
break;
|
|
|
|
case LValue::Kind_Upvalue:
|
|
bytecode.emitABC(set ? LOP_SETUPVAL : LOP_GETUPVAL, reg, lv.upval, 0);
|
|
break;
|
|
|
|
case LValue::Kind_Global:
|
|
{
|
|
int32_t cid = bytecode.addConstantString(lv.name);
|
|
if (cid < 0)
|
|
CompileError::raise(lv.location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
bytecode.emitABC(set ? LOP_SETGLOBAL : LOP_GETGLOBAL, reg, 0, uint8_t(BytecodeBuilder::getStringHash(lv.name)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
break;
|
|
|
|
case LValue::Kind_IndexName:
|
|
{
|
|
int32_t cid = bytecode.addConstantString(lv.name);
|
|
if (cid < 0)
|
|
CompileError::raise(lv.location, "Exceeded constant limit; simplify the code to compile");
|
|
|
|
bytecode.emitABC(set ? LOP_SETTABLEKS : LOP_GETTABLEKS, reg, lv.reg, uint8_t(BytecodeBuilder::getStringHash(lv.name)));
|
|
bytecode.emitAux(cid);
|
|
}
|
|
break;
|
|
|
|
case LValue::Kind_IndexNumber:
|
|
bytecode.emitABC(set ? LOP_SETTABLEN : LOP_GETTABLEN, reg, lv.reg, lv.number);
|
|
break;
|
|
|
|
case LValue::Kind_IndexExpr:
|
|
bytecode.emitABC(set ? LOP_SETTABLE : LOP_GETTABLE, reg, lv.reg, lv.index);
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unknown lvalue kind");
|
|
}
|
|
}
|
|
|
|
void compileAssign(const LValue& lv, uint8_t source)
|
|
{
|
|
compileLValueUse(lv, source, /* set= */ true);
|
|
}
|
|
|
|
bool isExprLocalReg(AstExpr* expr)
|
|
{
|
|
AstExprLocal* le = expr->as<AstExprLocal>();
|
|
if (!le || (!FFlag::LuauCompileSupportInlining && le->upvalue))
|
|
return false;
|
|
|
|
Local* l = locals.find(le->local);
|
|
|
|
return l && l->allocated;
|
|
}
|
|
|
|
bool isStatBreak(AstStat* node)
|
|
{
|
|
if (AstStatBlock* stat = node->as<AstStatBlock>())
|
|
return stat->body.size == 1 && stat->body.data[0]->is<AstStatBreak>();
|
|
|
|
return node->is<AstStatBreak>();
|
|
}
|
|
|
|
AstStatContinue* extractStatContinue(AstStatBlock* block)
|
|
{
|
|
if (block->body.size == 1)
|
|
return block->body.data[0]->as<AstStatContinue>();
|
|
else
|
|
return nullptr;
|
|
}
|
|
|
|
void compileStatIf(AstStatIf* stat)
|
|
{
|
|
// Optimization: condition is always false => we only need the else body
|
|
if (isConstantFalse(stat->condition))
|
|
{
|
|
if (stat->elsebody)
|
|
compileStat(stat->elsebody);
|
|
return;
|
|
}
|
|
|
|
// Optimization: body is a "break" statement with no "else" => we can directly break out of the loop in "then" case
|
|
if (!stat->elsebody && isStatBreak(stat->thenbody) && !areLocalsCaptured(loops.back().localOffset))
|
|
{
|
|
// fallthrough = continue with the loop as usual
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(stat->condition, nullptr, elseJump, true);
|
|
|
|
for (size_t jump : elseJump)
|
|
loopJumps.push_back({LoopJump::Break, jump});
|
|
return;
|
|
}
|
|
|
|
AstStat* continueStatement = extractStatContinue(stat->thenbody);
|
|
|
|
// Optimization: body is a "continue" statement with no "else" => we can directly continue in "then" case
|
|
if (!stat->elsebody && continueStatement != nullptr && !areLocalsCaptured(loops.back().localOffset))
|
|
{
|
|
if (loops.back().untilCondition)
|
|
validateContinueUntil(continueStatement, loops.back().untilCondition);
|
|
|
|
// fallthrough = proceed with the loop body as usual
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(stat->condition, nullptr, elseJump, true);
|
|
|
|
for (size_t jump : elseJump)
|
|
loopJumps.push_back({LoopJump::Continue, jump});
|
|
return;
|
|
}
|
|
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(stat->condition, nullptr, elseJump, false);
|
|
|
|
compileStat(stat->thenbody);
|
|
|
|
if (stat->elsebody && elseJump.size() > 0)
|
|
{
|
|
// we don't need to skip past "else" body if "then" ends with return
|
|
// this is important because, if "else" also ends with return, we may *not* have any statement to skip to!
|
|
if (allPathsEndWithReturn(stat->thenbody))
|
|
{
|
|
size_t elseLabel = bytecode.emitLabel();
|
|
|
|
compileStat(stat->elsebody);
|
|
|
|
patchJumps(stat, elseJump, elseLabel);
|
|
}
|
|
else
|
|
{
|
|
size_t thenLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
|
|
size_t elseLabel = bytecode.emitLabel();
|
|
|
|
compileStat(stat->elsebody);
|
|
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJumps(stat, elseJump, elseLabel);
|
|
patchJump(stat, thenLabel, endLabel);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJumps(stat, elseJump, endLabel);
|
|
}
|
|
}
|
|
|
|
void compileStatWhile(AstStatWhile* stat)
|
|
{
|
|
// Optimization: condition is always false => there's no loop!
|
|
if (isConstantFalse(stat->condition))
|
|
return;
|
|
|
|
size_t oldJumps = loopJumps.size();
|
|
size_t oldLocals = localStack.size();
|
|
|
|
loops.push_back({oldLocals, nullptr});
|
|
|
|
size_t loopLabel = bytecode.emitLabel();
|
|
|
|
std::vector<size_t> elseJump;
|
|
compileConditionValue(stat->condition, nullptr, elseJump, false);
|
|
|
|
compileStat(stat->body);
|
|
|
|
size_t contLabel = bytecode.emitLabel();
|
|
|
|
size_t backLabel = bytecode.emitLabel();
|
|
|
|
setDebugLine(stat->condition);
|
|
|
|
// Note: this is using JUMPBACK, not JUMP, since JUMPBACK is interruptible and we want all loops to have at least one interruptible
|
|
// instruction
|
|
bytecode.emitAD(LOP_JUMPBACK, 0, 0);
|
|
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJump(stat, backLabel, loopLabel);
|
|
patchJumps(stat, elseJump, endLabel);
|
|
|
|
patchLoopJumps(stat, oldJumps, endLabel, contLabel);
|
|
loopJumps.resize(oldJumps);
|
|
|
|
loops.pop_back();
|
|
}
|
|
|
|
void compileStatRepeat(AstStatRepeat* stat)
|
|
{
|
|
size_t oldJumps = loopJumps.size();
|
|
size_t oldLocals = localStack.size();
|
|
|
|
loops.push_back({oldLocals, stat->condition});
|
|
|
|
size_t loopLabel = bytecode.emitLabel();
|
|
|
|
// note: we "inline" compileStatBlock here so that we can close/pop locals after evaluating condition
|
|
// this is necessary because condition can access locals declared inside the repeat..until body
|
|
AstStatBlock* body = stat->body;
|
|
|
|
RegScope rs(this);
|
|
|
|
for (size_t i = 0; i < body->body.size; ++i)
|
|
compileStat(body->body.data[i]);
|
|
|
|
size_t contLabel = bytecode.emitLabel();
|
|
|
|
size_t endLabel;
|
|
|
|
setDebugLine(stat->condition);
|
|
|
|
if (isConstantTrue(stat->condition))
|
|
{
|
|
closeLocals(oldLocals);
|
|
|
|
endLabel = bytecode.emitLabel();
|
|
}
|
|
else
|
|
{
|
|
std::vector<size_t> skipJump;
|
|
compileConditionValue(stat->condition, nullptr, skipJump, true);
|
|
|
|
// we close locals *after* we compute loop conditionals because during computation of condition it's (in theory) possible that user code
|
|
// mutates them
|
|
closeLocals(oldLocals);
|
|
|
|
size_t backLabel = bytecode.emitLabel();
|
|
|
|
// Note: this is using JUMPBACK, not JUMP, since JUMPBACK is interruptible and we want all loops to have at least one interruptible
|
|
// instruction
|
|
bytecode.emitAD(LOP_JUMPBACK, 0, 0);
|
|
|
|
size_t skipLabel = bytecode.emitLabel();
|
|
|
|
// we need to close locals *again* after the loop ends because the first closeLocals would be jumped over on the last iteration
|
|
closeLocals(oldLocals);
|
|
|
|
endLabel = bytecode.emitLabel();
|
|
|
|
patchJump(stat, backLabel, loopLabel);
|
|
patchJumps(stat, skipJump, skipLabel);
|
|
}
|
|
|
|
popLocals(oldLocals);
|
|
|
|
patchLoopJumps(stat, oldJumps, endLabel, contLabel);
|
|
loopJumps.resize(oldJumps);
|
|
|
|
loops.pop_back();
|
|
}
|
|
|
|
void compileInlineReturn(AstStatReturn* stat, bool fallthrough)
|
|
{
|
|
setDebugLine(stat); // normally compileStat sets up line info, but compileInlineReturn can be called directly
|
|
|
|
InlineFrame frame = inlineFrames.back();
|
|
|
|
compileExprListTemp(stat->list, frame.target, frame.targetCount, /* targetTop= */ false);
|
|
|
|
if (!fallthrough)
|
|
{
|
|
size_t jumpLabel = bytecode.emitLabel();
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
|
|
inlineFrames.back().returnJumps.push_back(jumpLabel);
|
|
}
|
|
}
|
|
|
|
void compileStatReturn(AstStatReturn* stat)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
uint8_t temp = 0;
|
|
bool multRet = false;
|
|
|
|
// Optimization: return local value directly instead of copying it into a temporary
|
|
if (stat->list.size == 1 && isExprLocalReg(stat->list.data[0]))
|
|
{
|
|
AstExprLocal* le = stat->list.data[0]->as<AstExprLocal>();
|
|
LUAU_ASSERT(le);
|
|
|
|
temp = getLocal(le->local);
|
|
}
|
|
else if (stat->list.size > 0)
|
|
{
|
|
temp = allocReg(stat, unsigned(stat->list.size));
|
|
|
|
// Note: if the last element is a function call or a vararg specifier, then we need to somehow return all values that that call returned
|
|
for (size_t i = 0; i < stat->list.size; ++i)
|
|
if (i + 1 == stat->list.size)
|
|
multRet = compileExprTempMultRet(stat->list.data[i], uint8_t(temp + i));
|
|
else
|
|
compileExprTempTop(stat->list.data[i], uint8_t(temp + i));
|
|
}
|
|
|
|
closeLocals(0);
|
|
|
|
bytecode.emitABC(LOP_RETURN, uint8_t(temp), multRet ? 0 : uint8_t(stat->list.size + 1), 0);
|
|
}
|
|
|
|
bool areLocalsRedundant(AstStatLocal* stat)
|
|
{
|
|
// Extra expressions may have side effects
|
|
if (stat->values.size > stat->vars.size)
|
|
return false;
|
|
|
|
for (AstLocal* local : stat->vars)
|
|
{
|
|
Variable* v = variables.find(local);
|
|
|
|
if (!v || !v->constant)
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void compileStatLocal(AstStatLocal* stat)
|
|
{
|
|
// Optimization: we don't need to allocate and assign const locals, since their uses will be constant-folded
|
|
if (options.optimizationLevel >= 1 && options.debugLevel <= 1 && areLocalsRedundant(stat))
|
|
return;
|
|
|
|
// note: allocReg in this case allocates into parent block register - note that we don't have RegScope here
|
|
uint8_t vars = allocReg(stat, unsigned(stat->vars.size));
|
|
|
|
compileExprListTemp(stat->values, vars, uint8_t(stat->vars.size), /* targetTop= */ true);
|
|
|
|
for (size_t i = 0; i < stat->vars.size; ++i)
|
|
pushLocal(stat->vars.data[i], uint8_t(vars + i));
|
|
}
|
|
|
|
int getConstantShort(AstExpr* expr)
|
|
{
|
|
const Constant* c = constants.find(expr);
|
|
|
|
if (c && c->type == Constant::Type_Number)
|
|
{
|
|
double n = c->valueNumber;
|
|
|
|
if (n >= -32767 && n <= 32767 && double(int(n)) == n)
|
|
return int(n);
|
|
}
|
|
|
|
return INT_MIN;
|
|
}
|
|
|
|
bool canUnrollForBody(AstStatFor* stat)
|
|
{
|
|
struct CanUnrollVisitor : AstVisitor
|
|
{
|
|
bool result = true;
|
|
|
|
bool visit(AstExpr* node) override
|
|
{
|
|
// functions may capture loop variable, and our upval handling doesn't handle elided variables (constant)
|
|
// TODO: we could remove this case if we changed function compilation to create temporary locals for constant upvalues
|
|
result = result && !node->is<AstExprFunction>();
|
|
return result;
|
|
}
|
|
|
|
bool visit(AstStat* node) override
|
|
{
|
|
// while we can easily unroll nested loops, our cost model doesn't take unrolling into account so this can result in code explosion
|
|
// we also avoid continue/break since they introduce control flow across iterations
|
|
result = result && !node->is<AstStatFor>() && !node->is<AstStatContinue>() && !node->is<AstStatBreak>();
|
|
return result;
|
|
}
|
|
};
|
|
|
|
CanUnrollVisitor canUnroll;
|
|
stat->body->visit(&canUnroll);
|
|
|
|
return canUnroll.result;
|
|
}
|
|
|
|
bool tryCompileUnrolledFor(AstStatFor* stat, int thresholdBase, int thresholdMaxBoost)
|
|
{
|
|
int from = getConstantShort(stat->from);
|
|
int to = getConstantShort(stat->to);
|
|
int step = stat->step ? getConstantShort(stat->step) : 1;
|
|
|
|
// check that limits are reasonably small and trip count can be computed
|
|
if (from == INT_MIN || to == INT_MIN || step == INT_MIN || step == 0 || (step < 0 && to > from) || (step > 0 && to < from))
|
|
{
|
|
bytecode.addDebugRemark("loop unroll failed: invalid iteration count");
|
|
return false;
|
|
}
|
|
|
|
if (!canUnrollForBody(stat))
|
|
{
|
|
bytecode.addDebugRemark("loop unroll failed: unsupported loop body");
|
|
return false;
|
|
}
|
|
|
|
if (Variable* lv = variables.find(stat->var); lv && lv->written)
|
|
{
|
|
bytecode.addDebugRemark("loop unroll failed: mutable loop variable");
|
|
return false;
|
|
}
|
|
|
|
int tripCount = (to - from) / step + 1;
|
|
|
|
if (tripCount > thresholdBase)
|
|
{
|
|
bytecode.addDebugRemark("loop unroll failed: too many iterations (%d)", tripCount);
|
|
return false;
|
|
}
|
|
|
|
AstLocal* var = stat->var;
|
|
uint64_t costModel = modelCost(stat->body, &var, 1);
|
|
|
|
// we use a dynamic cost threshold that's based on the fixed limit boosted by the cost advantage we gain due to unrolling
|
|
bool varc = true;
|
|
int unrolledCost = computeCost(costModel, &varc, 1) * tripCount;
|
|
int baselineCost = (computeCost(costModel, nullptr, 0) + 1) * tripCount;
|
|
int unrollProfit = (unrolledCost == 0) ? thresholdMaxBoost : std::min(thresholdMaxBoost, 100 * baselineCost / unrolledCost);
|
|
|
|
int threshold = thresholdBase * unrollProfit / 100;
|
|
|
|
if (unrolledCost > threshold)
|
|
{
|
|
bytecode.addDebugRemark(
|
|
"loop unroll failed: too expensive (iterations %d, cost %d, profit %.2fx)", tripCount, unrolledCost, double(unrollProfit) / 100);
|
|
return false;
|
|
}
|
|
|
|
bytecode.addDebugRemark("loop unroll succeeded (iterations %d, cost %d, profit %.2fx)", tripCount, unrolledCost, double(unrollProfit) / 100);
|
|
|
|
for (int i = from; step > 0 ? i <= to : i >= to; i += step)
|
|
{
|
|
// we need to re-fold constants in the loop body with the new value; this reuses computed constant values elsewhere in the tree
|
|
locstants[var].type = Constant::Type_Number;
|
|
locstants[var].valueNumber = i;
|
|
|
|
foldConstants(constants, variables, locstants, stat);
|
|
|
|
compileStat(stat->body);
|
|
}
|
|
|
|
// clean up fold state in case we need to recompile - normally we compile the loop body once, but due to inlining we may need to do it again
|
|
locstants[var].type = Constant::Type_Unknown;
|
|
|
|
foldConstants(constants, variables, locstants, stat);
|
|
|
|
return true;
|
|
}
|
|
|
|
void compileStatFor(AstStatFor* stat)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
// Optimization: small loops can be unrolled when it is profitable
|
|
if (options.optimizationLevel >= 2 && isConstant(stat->to) && isConstant(stat->from) && (!stat->step || isConstant(stat->step)))
|
|
if (tryCompileUnrolledFor(stat, FInt::LuauCompileLoopUnrollThreshold, FInt::LuauCompileLoopUnrollThresholdMaxBoost))
|
|
return;
|
|
|
|
size_t oldLocals = localStack.size();
|
|
size_t oldJumps = loopJumps.size();
|
|
|
|
loops.push_back({oldLocals, nullptr});
|
|
|
|
// register layout: limit, step, index
|
|
uint8_t regs = allocReg(stat, 3);
|
|
|
|
// if the iteration index is assigned from within the loop, we need to protect the internal index from the assignment
|
|
// to do that, we will copy the index into an actual local variable on each iteration
|
|
// this makes sure the code inside the loop can't interfere with the iteration process (other than modifying the table we're iterating
|
|
// through)
|
|
uint8_t varreg = regs + 2;
|
|
|
|
if (Variable* il = variables.find(stat->var); il && il->written)
|
|
varreg = allocReg(stat, 1);
|
|
|
|
compileExprTemp(stat->from, uint8_t(regs + 2));
|
|
compileExprTemp(stat->to, uint8_t(regs + 0));
|
|
|
|
if (stat->step)
|
|
compileExprTemp(stat->step, uint8_t(regs + 1));
|
|
else
|
|
bytecode.emitABC(LOP_LOADN, uint8_t(regs + 1), 1, 0);
|
|
|
|
size_t forLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(LOP_FORNPREP, regs, 0);
|
|
|
|
size_t loopLabel = bytecode.emitLabel();
|
|
|
|
if (varreg != regs + 2)
|
|
bytecode.emitABC(LOP_MOVE, varreg, regs + 2, 0);
|
|
|
|
pushLocal(stat->var, varreg);
|
|
|
|
compileStat(stat->body);
|
|
|
|
closeLocals(oldLocals);
|
|
popLocals(oldLocals);
|
|
|
|
setDebugLine(stat);
|
|
|
|
size_t contLabel = bytecode.emitLabel();
|
|
|
|
size_t backLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(LOP_FORNLOOP, regs, 0);
|
|
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJump(stat, forLabel, endLabel);
|
|
patchJump(stat, backLabel, loopLabel);
|
|
|
|
patchLoopJumps(stat, oldJumps, endLabel, contLabel);
|
|
loopJumps.resize(oldJumps);
|
|
|
|
loops.pop_back();
|
|
}
|
|
|
|
void compileStatForIn(AstStatForIn* stat)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
size_t oldLocals = localStack.size();
|
|
size_t oldJumps = loopJumps.size();
|
|
|
|
loops.push_back({oldLocals, nullptr});
|
|
|
|
// register layout: generator, state, index, variables...
|
|
uint8_t regs = allocReg(stat, 3);
|
|
|
|
// this puts initial values of (generator, state, index) into the loop registers
|
|
compileExprListTemp(stat->values, regs, 3, /* targetTop= */ true);
|
|
|
|
// we don't need this because the extra stack space is just for calling the function with a loop protocol which is similar to calling
|
|
// metamethods - it should fit into the extra stack reservation
|
|
if (!FFlag::LuauCompileIterNoReserve)
|
|
{
|
|
// for the general case, we will execute a CALL for every iteration that needs to evaluate "variables... = generator(state, index)"
|
|
// this requires at least extra 3 stack slots after index
|
|
// note that these stack slots overlap with the variables so we only need to reserve them to make sure stack frame is large enough
|
|
reserveReg(stat, 3);
|
|
}
|
|
|
|
// note that we reserve at least 2 variables; this allows our fast path to assume that we need 2 variables instead of 1 or 2
|
|
uint8_t vars = allocReg(stat, std::max(unsigned(stat->vars.size), 2u));
|
|
LUAU_ASSERT(vars == regs + 3);
|
|
|
|
// Optimization: when we iterate through pairs/ipairs, we generate special bytecode that optimizes the traversal using internal iteration
|
|
// index These instructions dynamically check if generator is equal to next/inext and bail out They assume that the generator produces 2
|
|
// variables, which is why we allocate at least 2 above (see vars assignment)
|
|
LuauOpcode skipOp = FFlag::LuauCompileIter ? LOP_FORGPREP : LOP_JUMP;
|
|
LuauOpcode loopOp = LOP_FORGLOOP;
|
|
|
|
if (options.optimizationLevel >= 1 && stat->vars.size <= 2)
|
|
{
|
|
if (stat->values.size == 1 && stat->values.data[0]->is<AstExprCall>())
|
|
{
|
|
Builtin builtin = getBuiltin(stat->values.data[0]->as<AstExprCall>()->func, globals, variables);
|
|
|
|
if (builtin.isGlobal("ipairs")) // for .. in ipairs(t)
|
|
{
|
|
skipOp = LOP_FORGPREP_INEXT;
|
|
loopOp = LOP_FORGLOOP_INEXT;
|
|
}
|
|
else if (builtin.isGlobal("pairs")) // for .. in pairs(t)
|
|
{
|
|
skipOp = LOP_FORGPREP_NEXT;
|
|
loopOp = FFlag::LuauCompileIterNoPairs ? LOP_FORGLOOP : LOP_FORGLOOP_NEXT;
|
|
}
|
|
}
|
|
else if (stat->values.size == 2)
|
|
{
|
|
Builtin builtin = getBuiltin(stat->values.data[0], globals, variables);
|
|
|
|
if (builtin.isGlobal("next")) // for .. in next,t
|
|
{
|
|
skipOp = LOP_FORGPREP_NEXT;
|
|
loopOp = FFlag::LuauCompileIterNoPairs ? LOP_FORGLOOP : LOP_FORGLOOP_NEXT;
|
|
}
|
|
}
|
|
}
|
|
|
|
// first iteration jumps into FORGLOOP instruction, but for ipairs/pairs it does extra preparation that makes the cost of an extra instruction
|
|
// worthwhile
|
|
size_t skipLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(skipOp, regs, 0);
|
|
|
|
size_t loopLabel = bytecode.emitLabel();
|
|
|
|
for (size_t i = 0; i < stat->vars.size; ++i)
|
|
pushLocal(stat->vars.data[i], uint8_t(vars + i));
|
|
|
|
compileStat(stat->body);
|
|
|
|
closeLocals(oldLocals);
|
|
popLocals(oldLocals);
|
|
|
|
setDebugLine(stat);
|
|
|
|
size_t contLabel = bytecode.emitLabel();
|
|
|
|
size_t backLabel = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(loopOp, regs, 0);
|
|
|
|
// note: FORGLOOP needs variable count encoded in AUX field, other loop instructions assume a fixed variable count
|
|
if (loopOp == LOP_FORGLOOP)
|
|
bytecode.emitAux(uint32_t(stat->vars.size));
|
|
|
|
size_t endLabel = bytecode.emitLabel();
|
|
|
|
patchJump(stat, skipLabel, backLabel);
|
|
patchJump(stat, backLabel, loopLabel);
|
|
|
|
patchLoopJumps(stat, oldJumps, endLabel, contLabel);
|
|
loopJumps.resize(oldJumps);
|
|
|
|
loops.pop_back();
|
|
}
|
|
|
|
void resolveAssignConflicts(AstStat* stat, std::vector<LValue>& vars)
|
|
{
|
|
// regsUsed[i] is true if we have assigned the register during earlier assignments
|
|
// regsRemap[i] is set to the register where the original (pre-assignment) copy was made
|
|
// note: regsRemap is uninitialized intentionally to speed small assignments up; regsRemap[i] is valid iff regsUsed[i]
|
|
std::bitset<256> regsUsed;
|
|
uint8_t regsRemap[256];
|
|
|
|
for (size_t i = 0; i < vars.size(); ++i)
|
|
{
|
|
LValue& li = vars[i];
|
|
|
|
if (li.kind == LValue::Kind_Local)
|
|
{
|
|
if (!regsUsed[li.reg])
|
|
{
|
|
regsUsed[li.reg] = true;
|
|
regsRemap[li.reg] = li.reg;
|
|
}
|
|
}
|
|
else if (li.kind == LValue::Kind_IndexName || li.kind == LValue::Kind_IndexNumber || li.kind == LValue::Kind_IndexExpr)
|
|
{
|
|
// we're looking for assignments before this one that invalidate any of the registers involved
|
|
if (regsUsed[li.reg])
|
|
{
|
|
// the register may have been evacuated previously, but if it wasn't - move it now
|
|
if (regsRemap[li.reg] == li.reg)
|
|
{
|
|
uint8_t reg = allocReg(stat, 1);
|
|
bytecode.emitABC(LOP_MOVE, reg, li.reg, 0);
|
|
|
|
regsRemap[li.reg] = reg;
|
|
}
|
|
|
|
li.reg = regsRemap[li.reg];
|
|
}
|
|
|
|
if (li.kind == LValue::Kind_IndexExpr && regsUsed[li.index])
|
|
{
|
|
// the register may have been evacuated previously, but if it wasn't - move it now
|
|
if (regsRemap[li.index] == li.index)
|
|
{
|
|
uint8_t reg = allocReg(stat, 1);
|
|
bytecode.emitABC(LOP_MOVE, reg, li.index, 0);
|
|
|
|
regsRemap[li.index] = reg;
|
|
}
|
|
|
|
li.index = regsRemap[li.index];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void compileStatAssign(AstStatAssign* stat)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
// Optimization: one to one assignments don't require complex conflict resolution machinery and allow us to skip temporary registers for
|
|
// locals
|
|
if (stat->vars.size == 1 && stat->values.size == 1)
|
|
{
|
|
LValue var = compileLValue(stat->vars.data[0], rs);
|
|
|
|
// Optimization: assign to locals directly
|
|
if (var.kind == LValue::Kind_Local)
|
|
{
|
|
compileExpr(stat->values.data[0], var.reg);
|
|
}
|
|
else
|
|
{
|
|
uint8_t reg = compileExprAuto(stat->values.data[0], rs);
|
|
|
|
setDebugLine(stat->vars.data[0]);
|
|
compileAssign(var, reg);
|
|
}
|
|
return;
|
|
}
|
|
|
|
// compute all l-values: note that this doesn't assign anything yet but it allocates registers and computes complex expressions on the left
|
|
// hand side for example, in "a[expr] = foo" expr will get evaluated here
|
|
std::vector<LValue> vars(stat->vars.size);
|
|
|
|
for (size_t i = 0; i < stat->vars.size; ++i)
|
|
vars[i] = compileLValue(stat->vars.data[i], rs);
|
|
|
|
// perform conflict resolution: if any lvalue refers to a local reg that will be reassigned before that, we save the local variable in a
|
|
// temporary reg
|
|
resolveAssignConflicts(stat, vars);
|
|
|
|
// compute values into temporaries
|
|
uint8_t regs = allocReg(stat, unsigned(stat->vars.size));
|
|
|
|
compileExprListTemp(stat->values, regs, uint8_t(stat->vars.size), /* targetTop= */ true);
|
|
|
|
// assign variables that have associated values; note that if we have fewer values than variables, we'll assign nil because
|
|
// compileExprListTemp will generate nils
|
|
for (size_t i = 0; i < stat->vars.size; ++i)
|
|
{
|
|
setDebugLine(stat->vars.data[i]);
|
|
compileAssign(vars[i], uint8_t(regs + i));
|
|
}
|
|
}
|
|
|
|
void compileStatCompoundAssign(AstStatCompoundAssign* stat)
|
|
{
|
|
RegScope rs(this);
|
|
|
|
LValue var = compileLValue(stat->var, rs);
|
|
|
|
// Optimization: assign to locals directly
|
|
uint8_t target = (var.kind == LValue::Kind_Local) ? var.reg : allocReg(stat, 1);
|
|
|
|
switch (stat->op)
|
|
{
|
|
case AstExprBinary::Add:
|
|
case AstExprBinary::Sub:
|
|
case AstExprBinary::Mul:
|
|
case AstExprBinary::Div:
|
|
case AstExprBinary::Mod:
|
|
case AstExprBinary::Pow:
|
|
{
|
|
if (var.kind != LValue::Kind_Local)
|
|
compileLValueUse(var, target, /* set= */ false);
|
|
|
|
int32_t rc = getConstantNumber(stat->value);
|
|
|
|
if (rc >= 0 && rc <= 255)
|
|
{
|
|
bytecode.emitABC(getBinaryOpArith(stat->op, /* k= */ true), target, target, uint8_t(rc));
|
|
}
|
|
else
|
|
{
|
|
uint8_t rr = compileExprAuto(stat->value, rs);
|
|
|
|
bytecode.emitABC(getBinaryOpArith(stat->op), target, target, rr);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case AstExprBinary::Concat:
|
|
{
|
|
std::vector<AstExpr*> args = {stat->value};
|
|
|
|
// unroll the tree of concats down the right hand side to be able to do multiple ops
|
|
unrollConcats(args);
|
|
|
|
uint8_t regs = allocReg(stat, unsigned(1 + args.size()));
|
|
|
|
compileLValueUse(var, regs, /* set= */ false);
|
|
|
|
for (size_t i = 0; i < args.size(); ++i)
|
|
compileExprTemp(args[i], uint8_t(regs + 1 + i));
|
|
|
|
bytecode.emitABC(LOP_CONCAT, target, regs, uint8_t(regs + args.size()));
|
|
}
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unexpected compound assignment operation");
|
|
}
|
|
|
|
if (var.kind != LValue::Kind_Local)
|
|
compileAssign(var, target);
|
|
}
|
|
|
|
void compileStatFunction(AstStatFunction* stat)
|
|
{
|
|
// Optimization: compile value expresion directly into target local register
|
|
if (isExprLocalReg(stat->name))
|
|
{
|
|
AstExprLocal* le = stat->name->as<AstExprLocal>();
|
|
LUAU_ASSERT(le);
|
|
|
|
compileExpr(stat->func, getLocal(le->local));
|
|
return;
|
|
}
|
|
|
|
RegScope rs(this);
|
|
uint8_t reg = allocReg(stat, 1);
|
|
|
|
compileExprTemp(stat->func, reg);
|
|
|
|
LValue var = compileLValue(stat->name, rs);
|
|
compileAssign(var, reg);
|
|
}
|
|
|
|
void compileStat(AstStat* node)
|
|
{
|
|
setDebugLine(node);
|
|
|
|
if (options.coverageLevel >= 1 && needsCoverage(node))
|
|
{
|
|
bytecode.emitABC(LOP_COVERAGE, 0, 0, 0);
|
|
}
|
|
|
|
if (AstStatBlock* stat = node->as<AstStatBlock>())
|
|
{
|
|
RegScope rs(this);
|
|
|
|
size_t oldLocals = localStack.size();
|
|
|
|
for (size_t i = 0; i < stat->body.size; ++i)
|
|
compileStat(stat->body.data[i]);
|
|
|
|
closeLocals(oldLocals);
|
|
|
|
popLocals(oldLocals);
|
|
}
|
|
else if (AstStatIf* stat = node->as<AstStatIf>())
|
|
{
|
|
compileStatIf(stat);
|
|
}
|
|
else if (AstStatWhile* stat = node->as<AstStatWhile>())
|
|
{
|
|
compileStatWhile(stat);
|
|
}
|
|
else if (AstStatRepeat* stat = node->as<AstStatRepeat>())
|
|
{
|
|
compileStatRepeat(stat);
|
|
}
|
|
else if (node->is<AstStatBreak>())
|
|
{
|
|
LUAU_ASSERT(!loops.empty());
|
|
|
|
// before exiting out of the loop, we need to close all local variables that were captured in closures since loop start
|
|
// normally they are closed by the enclosing blocks, including the loop block, but we're skipping that here
|
|
closeLocals(loops.back().localOffset);
|
|
|
|
size_t label = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
|
|
loopJumps.push_back({LoopJump::Break, label});
|
|
}
|
|
else if (AstStatContinue* stat = node->as<AstStatContinue>())
|
|
{
|
|
LUAU_ASSERT(!loops.empty());
|
|
|
|
if (loops.back().untilCondition)
|
|
validateContinueUntil(stat, loops.back().untilCondition);
|
|
|
|
// before continuing, we need to close all local variables that were captured in closures since loop start
|
|
// normally they are closed by the enclosing blocks, including the loop block, but we're skipping that here
|
|
closeLocals(loops.back().localOffset);
|
|
|
|
size_t label = bytecode.emitLabel();
|
|
|
|
bytecode.emitAD(LOP_JUMP, 0, 0);
|
|
|
|
loopJumps.push_back({LoopJump::Continue, label});
|
|
}
|
|
else if (AstStatReturn* stat = node->as<AstStatReturn>())
|
|
{
|
|
if (options.optimizationLevel >= 2 && !inlineFrames.empty())
|
|
compileInlineReturn(stat, /* fallthrough= */ false);
|
|
else
|
|
compileStatReturn(stat);
|
|
}
|
|
else if (AstStatExpr* stat = node->as<AstStatExpr>())
|
|
{
|
|
// Optimization: since we don't need to read anything from the stack, we can compile the call to not return anything which saves register
|
|
// moves
|
|
if (AstExprCall* expr = stat->expr->as<AstExprCall>())
|
|
{
|
|
uint8_t target = uint8_t(regTop);
|
|
|
|
compileExprCall(expr, target, /* targetCount= */ 0);
|
|
}
|
|
else
|
|
{
|
|
RegScope rs(this);
|
|
compileExprAuto(stat->expr, rs);
|
|
}
|
|
}
|
|
else if (AstStatLocal* stat = node->as<AstStatLocal>())
|
|
{
|
|
compileStatLocal(stat);
|
|
}
|
|
else if (AstStatFor* stat = node->as<AstStatFor>())
|
|
{
|
|
compileStatFor(stat);
|
|
}
|
|
else if (AstStatForIn* stat = node->as<AstStatForIn>())
|
|
{
|
|
compileStatForIn(stat);
|
|
}
|
|
else if (AstStatAssign* stat = node->as<AstStatAssign>())
|
|
{
|
|
compileStatAssign(stat);
|
|
}
|
|
else if (AstStatCompoundAssign* stat = node->as<AstStatCompoundAssign>())
|
|
{
|
|
compileStatCompoundAssign(stat);
|
|
}
|
|
else if (AstStatFunction* stat = node->as<AstStatFunction>())
|
|
{
|
|
compileStatFunction(stat);
|
|
}
|
|
else if (AstStatLocalFunction* stat = node->as<AstStatLocalFunction>())
|
|
{
|
|
uint8_t var = allocReg(stat, 1);
|
|
|
|
pushLocal(stat->name, var);
|
|
compileExprFunction(stat->func, var);
|
|
|
|
Local& l = locals[stat->name];
|
|
|
|
// we *have* to pushLocal before we compile the function, since the function may refer to the local as an upvalue
|
|
// however, this means the debugpc for the local is at an instruction where the local value hasn't been computed yet
|
|
// to fix this we just move the debugpc after the local value is established
|
|
l.debugpc = bytecode.getDebugPC();
|
|
}
|
|
else if (node->is<AstStatTypeAlias>())
|
|
{
|
|
// do nothing
|
|
}
|
|
else
|
|
{
|
|
LUAU_ASSERT(!"Unknown statement type");
|
|
}
|
|
}
|
|
|
|
void validateContinueUntil(AstStat* cont, AstExpr* condition)
|
|
{
|
|
UndefinedLocalVisitor visitor(this);
|
|
condition->visit(&visitor);
|
|
|
|
if (visitor.undef)
|
|
CompileError::raise(condition->location,
|
|
"Local %s used in the repeat..until condition is undefined because continue statement on line %d jumps over it",
|
|
visitor.undef->name.value, cont->location.begin.line + 1);
|
|
}
|
|
|
|
void gatherConstUpvals(AstExprFunction* func)
|
|
{
|
|
ConstUpvalueVisitor visitor(this);
|
|
func->body->visit(&visitor);
|
|
|
|
for (AstLocal* local : visitor.upvals)
|
|
getUpval(local);
|
|
}
|
|
|
|
void pushLocal(AstLocal* local, uint8_t reg)
|
|
{
|
|
if (localStack.size() >= kMaxLocalCount)
|
|
CompileError::raise(
|
|
local->location, "Out of local registers when trying to allocate %s: exceeded limit %d", local->name.value, kMaxLocalCount);
|
|
|
|
localStack.push_back(local);
|
|
|
|
Local& l = locals[local];
|
|
|
|
LUAU_ASSERT(!l.allocated);
|
|
|
|
l.reg = reg;
|
|
l.allocated = true;
|
|
l.debugpc = bytecode.getDebugPC();
|
|
}
|
|
|
|
bool areLocalsCaptured(size_t start)
|
|
{
|
|
LUAU_ASSERT(start <= localStack.size());
|
|
|
|
for (size_t i = start; i < localStack.size(); ++i)
|
|
{
|
|
Local* l = locals.find(localStack[i]);
|
|
LUAU_ASSERT(l);
|
|
|
|
if (l->captured)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
void closeLocals(size_t start)
|
|
{
|
|
LUAU_ASSERT(start <= localStack.size());
|
|
|
|
bool captured = false;
|
|
uint8_t captureReg = 255;
|
|
|
|
for (size_t i = start; i < localStack.size(); ++i)
|
|
{
|
|
Local* l = locals.find(localStack[i]);
|
|
LUAU_ASSERT(l);
|
|
|
|
if (l->captured)
|
|
{
|
|
captured = true;
|
|
captureReg = std::min(captureReg, l->reg);
|
|
}
|
|
}
|
|
|
|
if (captured)
|
|
{
|
|
bytecode.emitABC(LOP_CLOSEUPVALS, captureReg, 0, 0);
|
|
}
|
|
}
|
|
|
|
void popLocals(size_t start)
|
|
{
|
|
LUAU_ASSERT(start <= localStack.size());
|
|
|
|
for (size_t i = start; i < localStack.size(); ++i)
|
|
{
|
|
Local* l = locals.find(localStack[i]);
|
|
LUAU_ASSERT(l);
|
|
LUAU_ASSERT(l->allocated);
|
|
|
|
l->allocated = false;
|
|
|
|
if (options.debugLevel >= 2)
|
|
{
|
|
uint32_t debugpc = bytecode.getDebugPC();
|
|
|
|
bytecode.pushDebugLocal(sref(localStack[i]->name), l->reg, l->debugpc, debugpc);
|
|
}
|
|
}
|
|
|
|
localStack.resize(start);
|
|
}
|
|
|
|
void patchJump(AstNode* node, size_t label, size_t target)
|
|
{
|
|
if (!bytecode.patchJumpD(label, target))
|
|
CompileError::raise(node->location, "Exceeded jump distance limit; simplify the code to compile");
|
|
}
|
|
|
|
void patchJumps(AstNode* node, std::vector<size_t>& labels, size_t target)
|
|
{
|
|
for (size_t l : labels)
|
|
patchJump(node, l, target);
|
|
}
|
|
|
|
void patchLoopJumps(AstNode* node, size_t oldJumps, size_t endLabel, size_t contLabel)
|
|
{
|
|
LUAU_ASSERT(oldJumps <= loopJumps.size());
|
|
|
|
for (size_t i = oldJumps; i < loopJumps.size(); ++i)
|
|
{
|
|
const LoopJump& lj = loopJumps[i];
|
|
|
|
switch (lj.type)
|
|
{
|
|
case LoopJump::Break:
|
|
patchJump(node, lj.label, endLabel);
|
|
break;
|
|
|
|
case LoopJump::Continue:
|
|
patchJump(node, lj.label, contLabel);
|
|
break;
|
|
|
|
default:
|
|
LUAU_ASSERT(!"Unknown loop jump type");
|
|
}
|
|
}
|
|
}
|
|
|
|
uint8_t allocReg(AstNode* node, unsigned int count)
|
|
{
|
|
unsigned int top = regTop;
|
|
if (top + count > kMaxRegisterCount)
|
|
CompileError::raise(node->location, "Out of registers when trying to allocate %d registers: exceeded limit %d", count, kMaxRegisterCount);
|
|
|
|
regTop += count;
|
|
stackSize = std::max(stackSize, regTop);
|
|
|
|
return uint8_t(top);
|
|
}
|
|
|
|
void reserveReg(AstNode* node, unsigned int count)
|
|
{
|
|
if (regTop + count > kMaxRegisterCount)
|
|
CompileError::raise(node->location, "Out of registers when trying to allocate %d registers: exceeded limit %d", count, kMaxRegisterCount);
|
|
|
|
stackSize = std::max(stackSize, regTop + count);
|
|
}
|
|
|
|
void setDebugLine(AstNode* node)
|
|
{
|
|
if (options.debugLevel >= 1)
|
|
bytecode.setDebugLine(node->location.begin.line + 1);
|
|
}
|
|
|
|
void setDebugLine(const Location& location)
|
|
{
|
|
if (options.debugLevel >= 1)
|
|
bytecode.setDebugLine(location.begin.line + 1);
|
|
}
|
|
|
|
void setDebugLineEnd(AstNode* node)
|
|
{
|
|
if (options.debugLevel >= 1)
|
|
bytecode.setDebugLine(node->location.end.line + 1);
|
|
}
|
|
|
|
bool needsCoverage(AstNode* node)
|
|
{
|
|
return !node->is<AstStatBlock>() && !node->is<AstStatTypeAlias>();
|
|
}
|
|
|
|
struct FenvVisitor : AstVisitor
|
|
{
|
|
bool& getfenvUsed;
|
|
bool& setfenvUsed;
|
|
|
|
FenvVisitor(bool& getfenvUsed, bool& setfenvUsed)
|
|
: getfenvUsed(getfenvUsed)
|
|
, setfenvUsed(setfenvUsed)
|
|
{
|
|
}
|
|
|
|
bool visit(AstExprGlobal* node) override
|
|
{
|
|
if (node->name == "getfenv")
|
|
getfenvUsed = true;
|
|
if (node->name == "setfenv")
|
|
setfenvUsed = true;
|
|
|
|
return false;
|
|
}
|
|
};
|
|
|
|
struct FunctionVisitor : AstVisitor
|
|
{
|
|
Compiler* self;
|
|
std::vector<AstExprFunction*>& functions;
|
|
|
|
FunctionVisitor(Compiler* self, std::vector<AstExprFunction*>& functions)
|
|
: self(self)
|
|
, functions(functions)
|
|
{
|
|
// preallocate the result; this works around std::vector's inefficient growth policy for small arrays
|
|
functions.reserve(16);
|
|
}
|
|
|
|
bool visit(AstExprFunction* node) override
|
|
{
|
|
node->body->visit(this);
|
|
|
|
// this makes sure all functions that are used when compiling this one have been already added to the vector
|
|
functions.push_back(node);
|
|
|
|
return false;
|
|
}
|
|
};
|
|
|
|
struct UndefinedLocalVisitor : AstVisitor
|
|
{
|
|
UndefinedLocalVisitor(Compiler* self)
|
|
: self(self)
|
|
, undef(nullptr)
|
|
{
|
|
}
|
|
|
|
void check(AstLocal* local)
|
|
{
|
|
Local& l = self->locals[local];
|
|
|
|
if (!l.allocated && !undef)
|
|
undef = local;
|
|
}
|
|
|
|
bool visit(AstExprLocal* node) override
|
|
{
|
|
if (!node->upvalue)
|
|
check(node->local);
|
|
|
|
return false;
|
|
}
|
|
|
|
bool visit(AstExprFunction* node) override
|
|
{
|
|
const Function* f = self->functions.find(node);
|
|
LUAU_ASSERT(f);
|
|
|
|
for (AstLocal* uv : f->upvals)
|
|
{
|
|
LUAU_ASSERT(uv->functionDepth < node->functionDepth);
|
|
|
|
if (uv->functionDepth == node->functionDepth - 1)
|
|
check(uv);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
Compiler* self;
|
|
AstLocal* undef;
|
|
};
|
|
|
|
struct ConstUpvalueVisitor : AstVisitor
|
|
{
|
|
ConstUpvalueVisitor(Compiler* self)
|
|
: self(self)
|
|
{
|
|
}
|
|
|
|
bool visit(AstExprLocal* node) override
|
|
{
|
|
if (node->upvalue && self->isConstant(node))
|
|
{
|
|
upvals.push_back(node->local);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool visit(AstExprFunction* node) override
|
|
{
|
|
// short-circuits the traversal to make it faster
|
|
return false;
|
|
}
|
|
|
|
Compiler* self;
|
|
std::vector<AstLocal*> upvals;
|
|
};
|
|
|
|
struct RegScope
|
|
{
|
|
RegScope(Compiler* self)
|
|
: self(self)
|
|
, oldTop(self->regTop)
|
|
{
|
|
}
|
|
|
|
// This ctor is useful to forcefully adjust the stack frame in case we know that registers after a certain point are scratch and can be
|
|
// discarded
|
|
RegScope(Compiler* self, unsigned int top)
|
|
: self(self)
|
|
, oldTop(self->regTop)
|
|
{
|
|
LUAU_ASSERT(top <= self->regTop);
|
|
self->regTop = top;
|
|
}
|
|
|
|
~RegScope()
|
|
{
|
|
self->regTop = oldTop;
|
|
}
|
|
|
|
Compiler* self;
|
|
unsigned int oldTop;
|
|
};
|
|
|
|
struct Function
|
|
{
|
|
uint32_t id;
|
|
std::vector<AstLocal*> upvals;
|
|
|
|
uint64_t costModel = 0;
|
|
unsigned int stackSize = 0;
|
|
bool canInline = false;
|
|
};
|
|
|
|
struct Local
|
|
{
|
|
uint8_t reg = 0;
|
|
bool allocated = false;
|
|
bool captured = false;
|
|
uint32_t debugpc = 0;
|
|
};
|
|
|
|
struct LoopJump
|
|
{
|
|
enum Type
|
|
{
|
|
Break,
|
|
Continue
|
|
};
|
|
|
|
Type type;
|
|
size_t label;
|
|
};
|
|
|
|
struct Loop
|
|
{
|
|
size_t localOffset;
|
|
|
|
AstExpr* untilCondition;
|
|
};
|
|
|
|
struct InlineFrame
|
|
{
|
|
AstExprFunction* func;
|
|
|
|
uint8_t target;
|
|
uint8_t targetCount;
|
|
|
|
std::vector<size_t> returnJumps;
|
|
};
|
|
|
|
BytecodeBuilder& bytecode;
|
|
|
|
CompileOptions options;
|
|
|
|
DenseHashMap<AstExprFunction*, Function> functions;
|
|
DenseHashMap<AstLocal*, Local> locals;
|
|
DenseHashMap<AstName, Global> globals;
|
|
DenseHashMap<AstLocal*, Variable> variables;
|
|
DenseHashMap<AstExpr*, Constant> constants;
|
|
DenseHashMap<AstLocal*, Constant> locstants;
|
|
DenseHashMap<AstExprTable*, TableShape> tableShapes;
|
|
|
|
unsigned int regTop = 0;
|
|
unsigned int stackSize = 0;
|
|
|
|
bool getfenvUsed = false;
|
|
bool setfenvUsed = false;
|
|
|
|
std::vector<AstLocal*> localStack;
|
|
std::vector<AstLocal*> upvals;
|
|
std::vector<LoopJump> loopJumps;
|
|
std::vector<Loop> loops;
|
|
std::vector<InlineFrame> inlineFrames;
|
|
};
|
|
|
|
void compileOrThrow(BytecodeBuilder& bytecode, AstStatBlock* root, const AstNameTable& names, const CompileOptions& options)
|
|
{
|
|
LUAU_TIMETRACE_SCOPE("compileOrThrow", "Compiler");
|
|
|
|
Compiler compiler(bytecode, options);
|
|
|
|
// since access to some global objects may result in values that change over time, we block imports from non-readonly tables
|
|
assignMutable(compiler.globals, names, options.mutableGlobals);
|
|
|
|
// this pass analyzes mutability of locals/globals and associates locals with their initial values
|
|
trackValues(compiler.globals, compiler.variables, root);
|
|
|
|
if (options.optimizationLevel >= 1)
|
|
{
|
|
// this pass analyzes constantness of expressions
|
|
foldConstants(compiler.constants, compiler.variables, compiler.locstants, root);
|
|
|
|
// this pass analyzes table assignments to estimate table shapes for initially empty tables
|
|
predictTableShapes(compiler.tableShapes, root);
|
|
}
|
|
|
|
// this visitor tracks calls to getfenv/setfenv and disables some optimizations when they are found
|
|
if (options.optimizationLevel >= 1 && (names.get("getfenv").value || names.get("setfenv").value))
|
|
{
|
|
Compiler::FenvVisitor fenvVisitor(compiler.getfenvUsed, compiler.setfenvUsed);
|
|
root->visit(&fenvVisitor);
|
|
}
|
|
|
|
// gathers all functions with the invariant that all function references are to functions earlier in the list
|
|
// for example, function foo() return function() end end will result in two vector entries, [0] = anonymous and [1] = foo
|
|
std::vector<AstExprFunction*> functions;
|
|
Compiler::FunctionVisitor functionVisitor(&compiler, functions);
|
|
root->visit(&functionVisitor);
|
|
|
|
for (AstExprFunction* expr : functions)
|
|
compiler.compileFunction(expr);
|
|
|
|
AstExprFunction main(root->location, /*generics= */ AstArray<AstGenericType>(), /*genericPacks= */ AstArray<AstGenericTypePack>(),
|
|
/* self= */ nullptr, AstArray<AstLocal*>(), /* vararg= */ Luau::Location(), root, /* functionDepth= */ 0, /* debugname= */ AstName());
|
|
uint32_t mainid = compiler.compileFunction(&main);
|
|
|
|
bytecode.setMainFunction(mainid);
|
|
bytecode.finalize();
|
|
}
|
|
|
|
void compileOrThrow(BytecodeBuilder& bytecode, const std::string& source, const CompileOptions& options, const ParseOptions& parseOptions)
|
|
{
|
|
Allocator allocator;
|
|
AstNameTable names(allocator);
|
|
ParseResult result = Parser::parse(source.c_str(), source.size(), names, allocator, parseOptions);
|
|
|
|
if (!result.errors.empty())
|
|
throw ParseErrors(result.errors);
|
|
|
|
AstStatBlock* root = result.root;
|
|
|
|
compileOrThrow(bytecode, root, names, options);
|
|
}
|
|
|
|
std::string compile(const std::string& source, const CompileOptions& options, const ParseOptions& parseOptions, BytecodeEncoder* encoder)
|
|
{
|
|
LUAU_TIMETRACE_SCOPE("compile", "Compiler");
|
|
|
|
Allocator allocator;
|
|
AstNameTable names(allocator);
|
|
ParseResult result = Parser::parse(source.c_str(), source.size(), names, allocator, parseOptions);
|
|
|
|
if (!result.errors.empty())
|
|
{
|
|
// Users of this function expect only a single error message
|
|
const Luau::ParseError& parseError = result.errors.front();
|
|
std::string error = format(":%d: %s", parseError.getLocation().begin.line + 1, parseError.what());
|
|
|
|
return BytecodeBuilder::getError(error);
|
|
}
|
|
|
|
try
|
|
{
|
|
BytecodeBuilder bcb(encoder);
|
|
compileOrThrow(bcb, result.root, names, options);
|
|
|
|
return bcb.getBytecode();
|
|
}
|
|
catch (CompileError& e)
|
|
{
|
|
std::string error = format(":%d: %s", e.getLocation().begin.line + 1, e.what());
|
|
return BytecodeBuilder::getError(error);
|
|
}
|
|
}
|
|
|
|
} // namespace Luau
|