782358 - Move interpreter argument type checks from the caller to the callee

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Jan de Mooij [:jandem]]

Attachment: WIP

Currently TypeMonitorCall is used at the call site to monitor the types of the callee's |this| and arguments. This can cause problems in two cases:

(1) When a native like array.sort calls a scripted function, we always monitor the argument types in InvokeKernel - it would be more efficient to do it in JIT code if the function is hot enough to be compiled. This helps string-tagcloud.

(2) When an interpreted function calls another function many times, the callee will be hot before the caller, so it's more efficient to have the callee do the argument type checks (since the JITs can inline them). This helps crypto-md5.

The attached WIP patch does this, passes jit-tests and wins 10% on crypto-md5 and 5% on string-tagcloud. It's just a few ms of course, but the difference between us and v8 on SS is less than 10 ms anyway..

Comment 1

[Jan de Mooij [:jandem]]

Not worth it with baseline.