luau-src-rs/luau/Compiler/src/BuiltinFolding.cpp

465 lines
13 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#include "BuiltinFolding.h"
#include "Luau/Bytecode.h"
#include <math.h>
namespace Luau
{
namespace Compile
{
const double kRadDeg = 3.14159265358979323846 / 180.0;
static Constant cvar()
{
return Constant();
}
static Constant cbool(bool v)
{
Constant res = {Constant::Type_Boolean};
res.valueBoolean = v;
return res;
}
static Constant cnum(double v)
{
Constant res = {Constant::Type_Number};
res.valueNumber = v;
return res;
}
static Constant cstring(const char* v)
{
Constant res = {Constant::Type_String};
res.stringLength = unsigned(strlen(v));
res.valueString = v;
return res;
}
static Constant ctype(const Constant& c)
{
LUAU_ASSERT(c.type != Constant::Type_Unknown);
switch (c.type)
{
case Constant::Type_Nil:
return cstring("nil");
case Constant::Type_Boolean:
return cstring("boolean");
case Constant::Type_Number:
return cstring("number");
case Constant::Type_String:
return cstring("string");
default:
LUAU_ASSERT(!"Unsupported constant type");
return cvar();
}
}
static uint32_t bit32(double v)
{
// convert through signed 64-bit integer to match runtime behavior and gracefully truncate negative integers
return uint32_t(int64_t(v));
}
Constant foldBuiltin(int bfid, const Constant* args, size_t count)
{
switch (bfid)
{
case LBF_MATH_ABS:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(fabs(args[0].valueNumber));
break;
case LBF_MATH_ACOS:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(acos(args[0].valueNumber));
break;
case LBF_MATH_ASIN:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(asin(args[0].valueNumber));
break;
case LBF_MATH_ATAN2:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
return cnum(atan2(args[0].valueNumber, args[1].valueNumber));
break;
case LBF_MATH_ATAN:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(atan(args[0].valueNumber));
break;
case LBF_MATH_CEIL:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(ceil(args[0].valueNumber));
break;
case LBF_MATH_COSH:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(cosh(args[0].valueNumber));
break;
case LBF_MATH_COS:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(cos(args[0].valueNumber));
break;
case LBF_MATH_DEG:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(args[0].valueNumber / kRadDeg);
break;
case LBF_MATH_EXP:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(exp(args[0].valueNumber));
break;
case LBF_MATH_FLOOR:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(floor(args[0].valueNumber));
break;
case LBF_MATH_FMOD:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
return cnum(fmod(args[0].valueNumber, args[1].valueNumber));
break;
// Note: FREXP isn't folded since it returns multiple values
case LBF_MATH_LDEXP:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
return cnum(ldexp(args[0].valueNumber, int(args[1].valueNumber)));
break;
case LBF_MATH_LOG10:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(log10(args[0].valueNumber));
break;
case LBF_MATH_LOG:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(log(args[0].valueNumber));
else if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
if (args[1].valueNumber == 2.0)
return cnum(log2(args[0].valueNumber));
else if (args[1].valueNumber == 10.0)
return cnum(log10(args[0].valueNumber));
else
return cnum(log(args[0].valueNumber) / log(args[1].valueNumber));
}
break;
case LBF_MATH_MAX:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
double r = args[0].valueNumber;
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
double a = args[i].valueNumber;
r = (a > r) ? a : r;
}
return cnum(r);
}
break;
case LBF_MATH_MIN:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
double r = args[0].valueNumber;
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
double a = args[i].valueNumber;
r = (a < r) ? a : r;
}
return cnum(r);
}
break;
// Note: MODF isn't folded since it returns multiple values
case LBF_MATH_POW:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
return cnum(pow(args[0].valueNumber, args[1].valueNumber));
break;
case LBF_MATH_RAD:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(args[0].valueNumber * kRadDeg);
break;
case LBF_MATH_SINH:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(sinh(args[0].valueNumber));
break;
case LBF_MATH_SIN:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(sin(args[0].valueNumber));
break;
case LBF_MATH_SQRT:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(sqrt(args[0].valueNumber));
break;
case LBF_MATH_TANH:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(tanh(args[0].valueNumber));
break;
case LBF_MATH_TAN:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(tan(args[0].valueNumber));
break;
case LBF_BIT32_ARSHIFT:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
uint32_t u = bit32(args[0].valueNumber);
int s = int(args[1].valueNumber);
if (unsigned(s) < 32)
return cnum(double(uint32_t(int32_t(u) >> s)));
}
break;
case LBF_BIT32_BAND:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
uint32_t r = bit32(args[0].valueNumber);
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
r &= bit32(args[i].valueNumber);
}
return cnum(double(r));
}
break;
case LBF_BIT32_BNOT:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(double(uint32_t(~bit32(args[0].valueNumber))));
break;
case LBF_BIT32_BOR:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
uint32_t r = bit32(args[0].valueNumber);
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
r |= bit32(args[i].valueNumber);
}
return cnum(double(r));
}
break;
case LBF_BIT32_BXOR:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
uint32_t r = bit32(args[0].valueNumber);
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
r ^= bit32(args[i].valueNumber);
}
return cnum(double(r));
}
break;
case LBF_BIT32_BTEST:
if (count >= 1 && args[0].type == Constant::Type_Number)
{
uint32_t r = bit32(args[0].valueNumber);
for (size_t i = 1; i < count; ++i)
{
if (args[i].type != Constant::Type_Number)
return cvar();
r &= bit32(args[i].valueNumber);
}
return cbool(r != 0);
}
break;
case LBF_BIT32_EXTRACT:
if (count >= 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number &&
(count == 2 || args[2].type == Constant::Type_Number))
{
uint32_t u = bit32(args[0].valueNumber);
int f = int(args[1].valueNumber);
int w = count == 2 ? 1 : int(args[2].valueNumber);
if (f >= 0 && w > 0 && f + w <= 32)
{
uint32_t m = ~(0xfffffffeu << (w - 1));
return cnum(double((u >> f) & m));
}
}
break;
case LBF_BIT32_LROTATE:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
uint32_t u = bit32(args[0].valueNumber);
int s = int(args[1].valueNumber);
return cnum(double((u << (s & 31)) | (u >> ((32 - s) & 31))));
}
break;
case LBF_BIT32_LSHIFT:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
uint32_t u = bit32(args[0].valueNumber);
int s = int(args[1].valueNumber);
if (unsigned(s) < 32)
return cnum(double(u << s));
}
break;
case LBF_BIT32_REPLACE:
if (count >= 3 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number && args[2].type == Constant::Type_Number &&
(count == 3 || args[3].type == Constant::Type_Number))
{
uint32_t n = bit32(args[0].valueNumber);
uint32_t v = bit32(args[1].valueNumber);
int f = int(args[2].valueNumber);
int w = count == 3 ? 1 : int(args[3].valueNumber);
if (f >= 0 && w > 0 && f + w <= 32)
{
uint32_t m = ~(0xfffffffeu << (w - 1));
return cnum(double((n & ~(m << f)) | ((v & m) << f)));
}
}
break;
case LBF_BIT32_RROTATE:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
uint32_t u = bit32(args[0].valueNumber);
int s = int(args[1].valueNumber);
return cnum(double((u >> (s & 31)) | (u << ((32 - s) & 31))));
}
break;
case LBF_BIT32_RSHIFT:
if (count == 2 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number)
{
uint32_t u = bit32(args[0].valueNumber);
int s = int(args[1].valueNumber);
if (unsigned(s) < 32)
return cnum(double(u >> s));
}
break;
case LBF_TYPE:
if (count == 1 && args[0].type != Constant::Type_Unknown)
return ctype(args[0]);
break;
case LBF_STRING_BYTE:
if (count == 1 && args[0].type == Constant::Type_String)
{
if (args[0].stringLength > 0)
return cnum(double(uint8_t(args[0].valueString[0])));
}
else if (count == 2 && args[0].type == Constant::Type_String && args[1].type == Constant::Type_Number)
{
int i = int(args[1].valueNumber);
if (i > 0 && unsigned(i) <= args[0].stringLength)
return cnum(double(uint8_t(args[0].valueString[i - 1])));
}
break;
case LBF_STRING_LEN:
if (count == 1 && args[0].type == Constant::Type_String)
return cnum(double(args[0].stringLength));
break;
case LBF_TYPEOF:
if (count == 1 && args[0].type != Constant::Type_Unknown)
return ctype(args[0]);
break;
case LBF_MATH_CLAMP:
if (count == 3 && args[0].type == Constant::Type_Number && args[1].type == Constant::Type_Number && args[2].type == Constant::Type_Number)
{
double min = args[1].valueNumber;
double max = args[2].valueNumber;
if (min <= max)
{
double v = args[0].valueNumber;
v = v < min ? min : v;
v = v > max ? max : v;
return cnum(v);
}
}
break;
case LBF_MATH_SIGN:
if (count == 1 && args[0].type == Constant::Type_Number)
{
double v = args[0].valueNumber;
return cnum(v > 0.0 ? 1.0 : v < 0.0 ? -1.0 : 0.0);
}
break;
case LBF_MATH_ROUND:
if (count == 1 && args[0].type == Constant::Type_Number)
return cnum(round(args[0].valueNumber));
break;
}
return cvar();
}
} // namespace Compile
} // namespace Luau