RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-26 07:07:45 +00:00
Code Issues Activity Actions

LibJS/JIT: Add fast path for Increment with Int32 value

Browse source 
This uses a new branch_if_int32() mechanism that takes a code generating
lambda whose code will run if the input register is an Int32 JS::Value.
This commit is contained in:
Andreas Kling 2023-10-23 10:20:35 +02:00
parent aeb9bd3bf1
commit ea65214c57
3 changed files with 99 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

63
Userland/Libraries/LibJS/JIT/Compiler.cpp
View file

@ -162,18 +162,81 @@ void Compiler::compile_jump_conditional(Bytecode::Op::JumpConditional const& op)
[[maybe_unused]] static Value cxx_increment(VM& vm, Value value)
{
dbgln("cxx_increment {}", value);
auto old_value = TRY_OR_SET_EXCEPTION(value.to_numeric(vm));
if (old_value.is_number())
return Value(old_value.as_double() + 1);
return BigInt::create(vm, old_value.as_bigint().big_integer().plus(Crypto::SignedBigInteger { 1 }));
}
template<typename Codegen>
void Compiler::branch_if_int32(Assembler::Reg reg, Codegen codegen)
{
// GPR0 = reg >> 48;
m_assembler.mov(Assembler::Operand::Register(GPR0), Assembler::Operand::Register(reg));
m_assembler.shift_right(Assembler::Operand::Register(GPR0), Assembler::Operand::Imm8(48));
auto not_int32_case = m_assembler.make_label();
m_assembler.jump_if_not_equal(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Imm32(INT32_TAG),
not_int32_case);
codegen();
not_int32_case.link(m_assembler);
}
void Compiler::compile_increment(Bytecode::Op::Increment const&)
{
load_vm_register(ARG1, Bytecode::Register::accumulator());
auto end = m_assembler.make_label();
auto slow_case = m_assembler.make_label();
branch_if_int32(ARG1, [&] {
// GPR0 = ARG1 & 0xffffffff;
m_assembler.mov(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Register(ARG1));
m_assembler.mov(
Assembler::Operand::Register(GPR1),
Assembler::Operand::Imm64(0xffffffff));
m_assembler.bitwise_and(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Register(GPR1));
// if (GPR0 == 0x7fffffff) goto slow_case;
m_assembler.jump_if_equal(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Imm32(0x7fffffff),
slow_case);
// GPR0 += 1;
m_assembler.add(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Imm32(1));
// GPR0 |= INT32_TAG << 48;
m_assembler.mov(
Assembler::Operand::Register(GPR1),
Assembler::Operand::Imm64(SHIFTED_INT32_TAG));
m_assembler.bitwise_or(
Assembler::Operand::Register(GPR0),
Assembler::Operand::Register(GPR1));
// accumulator = GPR0;
store_vm_register(Bytecode::Register::accumulator(), GPR0);
m_assembler.jump(end);
});
slow_case.link(m_assembler);
m_assembler.native_call((void*)cxx_increment);
store_vm_register(Bytecode::Register::accumulator(), RET);
check_exception();
end.link(m_assembler);
}
static Value cxx_decrement(VM& vm, Value value)