Don't create a stack frame for Hash#key?

This commit is contained in:
Maxime Chevalier-Boisvert 2020-10-27 15:58:26 -04:00 committed by Alan Wu
parent 5413d0918b
commit 0c52371c47

View File

@ -483,6 +483,21 @@ gen_opt_minus(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
return true; return true;
} }
MJIT_FUNC_EXPORTED VALUE rb_hash_has_key(VALUE hash, VALUE key);
bool
cfunc_needs_frame(const rb_method_cfunc_t *cfunc)
{
void* fptr = (void*)cfunc->func;
// Leaf C functions do not need a stack frame
// or a stack overflow check
return !(
// Hash#key?
fptr == (void*)rb_hash_has_key
);
}
bool bool
gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx) gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
{ {
@ -590,13 +605,9 @@ gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
test(cb, flags_opnd, imm_opnd(IMEMO_FL_USER5)); test(cb, flags_opnd, imm_opnd(IMEMO_FL_USER5));
jnz_ptr(cb, side_exit); jnz_ptr(cb, side_exit);
// IDEA: stack frame setup may not be needed for some C functions // If this function needs a Ruby stack frame
// We could profile the most called C functions and identify which are safe if (cfunc_needs_frame(cfunc))
// This may help us eliminate stack overflow checks as well {
// Stack overflow check // Stack overflow check
// #define CHECK_VM_STACK_OVERFLOW0(cfp, sp, margin) // #define CHECK_VM_STACK_OVERFLOW0(cfp, sp, margin)
// REG_CFP <= REG_SP + 4 * sizeof(VALUE) + sizeof(rb_control_frame_t) // REG_CFP <= REG_SP + 4 * sizeof(VALUE) + sizeof(rb_control_frame_t)
@ -648,6 +659,7 @@ gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
mov(cb, member_opnd(REG1, rb_control_frame_t, ep), REG0); mov(cb, member_opnd(REG1, rb_control_frame_t, ep), REG0);
mov(cb, REG0, recv); mov(cb, REG0, recv);
mov(cb, member_opnd(REG1, rb_control_frame_t, self), REG0); mov(cb, member_opnd(REG1, rb_control_frame_t, self), REG0);
}
// Save the MicroJIT registers // Save the MicroJIT registers
push(cb, REG_CFP); push(cb, REG_CFP);
@ -693,12 +705,16 @@ gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
x86opnd_t stack_ret = ctx_stack_push(ctx, 1); x86opnd_t stack_ret = ctx_stack_push(ctx, 1);
mov(cb, stack_ret, RAX); mov(cb, stack_ret, RAX);
// If this function needs a Ruby stack frame
if (cfunc_needs_frame(cfunc))
{
// Pop the stack frame (ec->cfp++) // Pop the stack frame (ec->cfp++)
add( add(
cb, cb,
member_opnd(REG_EC, rb_execution_context_t, cfp), member_opnd(REG_EC, rb_execution_context_t, cfp),
imm_opnd(sizeof(rb_control_frame_t)) imm_opnd(sizeof(rb_control_frame_t))
); );
}
return true; return true;
} }