It is hard to tell with all of the p4 noise, but it seems to have gotten some generally very strong improvements. Showing 14% on fibonacci, although I'm skeptical. I guess will have to watch for a few more checkins and see if it stays that way.
On Wed, Sep 24, 2008 at 6:27 PM, Kasper Lund <[EMAIL PROTECTED]> wrote: > > LGTM and the ARM code already deals with the stack checks differently > so no need to mess with that. > > On Wed, Sep 24, 2008 at 3:04 PM, <[EMAIL PROTECTED]> wrote: >> >> Reviewers: Kasper Lund, Kevin Millikin, >> >> Message: >> I imagine this was originally done with some reason, we now have more >> code in the main body, where before the stack failure call would have >> been pushed to the bottom. However, we will save 4 bytes when we can >> use a short jcc, so this will mean it's only 1 byte more in the main >> body, and nothing at the end, so I think it's a definite win. >> >> Description: >> Don't defer the stack check failure code. It is a CallStub, which will >> be a single 5 byte call instruction. This should cause equivalent code >> size now, but opens up the opportunity to make one of the most common >> jcc's to use short encoding in the future. >> >> Please review this at http://codereview.chromium.org/4066 >> >> Affected files: >> M src/codegen-ia32.cc >> >> >> Index: src/codegen-ia32.cc >> diff --git a/src/codegen-ia32.cc b/src/codegen-ia32.cc >> index >> 6a522c57988ef2a97ca16d61019c7c62256054b1..ce1bce6fe88c0a8c6855e64aac9517c8b3a99f45 >> 100644 >> --- a/src/codegen-ia32.cc >> +++ b/src/codegen-ia32.cc >> @@ -2660,30 +2660,16 @@ void Ia32CodeGenerator::Branch(bool if_true, Label* >> L) { >> } >> >> >> -class StackCheckDeferred: public DeferredCode { >> - public: >> - explicit StackCheckDeferred(CodeGenerator* generator) >> - : DeferredCode(generator) { >> - set_comment("[ StackCheckDeferred"); >> - } >> - virtual void Generate(); >> -}; >> - >> - >> -void StackCheckDeferred::Generate() { >> - StackCheckStub stub; >> - __ CallStub(&stub); >> -} >> - >> - >> void Ia32CodeGenerator::CheckStack() { >> if (FLAG_check_stack) { >> - StackCheckDeferred* deferred = new StackCheckDeferred(this); >> + Label stack_is_ok; >> + StackCheckStub stub; >> ExternalReference stack_guard_limit = >> ExternalReference::address_of_stack_guard_limit(); >> __ cmp(esp, Operand::StaticVariable(stack_guard_limit)); >> - __ j(below, deferred->enter(), not_taken); >> - __ bind(deferred->exit()); >> + __ j(above_equal, &stack_is_ok, taken); >> + __ CallStub(&stub); >> + __ bind(&stack_is_ok); >> } >> } >> >> >> >> >> > >> > > > > --~--~---------~--~----~------------~-------~--~----~ v8-dev mailing list v8-dev@googlegroups.com http://groups.google.com/group/v8-dev -~----------~----~----~----~------~----~------~--~---
