A potential issue with this change is creating lots of maps when
objects flip between fast/slow elements modes. We could add special
transitions to avoid this. Yet testing this on our benchmarks, gmail,
and wave seems to indicate that this is not a real problem.
Review URL: http://codereview.chromium.org/2870018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4941 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Similar or duplicate checks are scattered around the code before doing the dictionary load.
Also the entire branch in GenerateCallNormal that handles global/builtin receiver is
guaranteed to bail out from GenerateDictionaryLoad, so there is no point in generating it at all.
The purpose of the patch is:
- making C++ code more compact and transparent,
- not generating dead code.
There is a tiny performance gain. The patch is ia32 only for now.
Please tell me if I am missing anything.
Review URL: http://codereview.chromium.org/2801007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4926 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Zhang Kun. For now we only emit movw and movt in places where no
relocation is needed. Small performance boost (around 0.5%).
Also adds support for turning ALU operations (eor etc.) with
large immediates into mvn or movw followed by a register-based
ALU operation.
Review URL: http://codereview.chromium.org/2821014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4913 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If a two-byte string only contains ascii characters, then we can save
memory when flattening a cons string containing it. Similarly we can
use this in Array.prototype.join implementation. To track this a new
bit is added to instance type. This bit is used as a hint in generated
code and in runtime functions.
To enable testing a new V8 extension is added controlled by
--expose-externalize-string flag.
Review URL: http://codereview.chromium.org/2762008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4894 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Generating code for function return on ARM is now aligned with the other platforms. The first non-shadowed return statement encountered will emit code for function return and all other returns including the fall through at the bottom of a function will jump to that.
Review URL: http://codereview.chromium.org/2815003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4856 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
With the change in r4820 all return statements are now breakable like any statement, so stepping will stop before the return statement actually returning from a function. With this change the position when breaking in the function return (after executing the return statement) will be the actual end of the function. At this point the return value is available as it saved to the stack by the debug break at return handling. Added information on the actual value returned from the function to the debugger.
Review URL: http://codereview.chromium.org/2783002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4835 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added support for more precise break points when debugging and stepping. To achieve that additional nop instructions are inserted where breaking would otherwise be impossible. The number of nop instructions inserted are sufficient to make place for patching with a call to a debug break code stub. On Intel that is 5 nop's for 32-bit and 13 for 64-bit. Om ARM 3 nop instructions (12 bytes) are required.
In order to avoid inserting nop's in to many places a simple ast checker have been added to check whether there are breakable code in a statement or expression. If it is possible to break in an expression no additional break enabeling code is inserted.
Added break locations to the true and false part of a conditional expression.
Added stepping tests to cover more constructs.
These changes are only in the full compiler.
Changed the default value for the option --debugger in teh d8 shell from true to false. The reason for this is that with --debugger turned on the full compiler will be used for all code in when running d8, which can be unexpeceted.
Review URL: http://codereview.chromium.org/2693002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4820 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in a spilled scope or not. Also get rid of some spilled scopes
that we don't need any more. The generators for the %_ functions,
CodeGenerator::Generate*, are now not spilled by default. Some
of them (IsObject and related) have been converted to register
allocated operation.
Review URL: http://codereview.chromium.org/2368001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4749 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Support building with or without unaligned accesses by using scons flag simulatorunalignedaccesses.
$ scons simulator=arm simulatorunalignedaccesses=off
$ scons simulator=arm simulatorunalignedaccesses=on
If simulatorunalignedaccesses is not specified (or specified as default) the default is to use unaligned accesses.
Review URL: http://codereview.chromium.org/2218003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4737 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
NumberToUint32 that I was trying to use maps -0 to +0 (as desired) but
also maps +/-Infinity to +0, which made +/-Infinity a valid string
index. I fixed it by introducing a new runtime function with the right
semantics.
TEST=LayoutTests/fast/js/char-at.html,mjsunit/string-charat.js
Review URL: http://codereview.chromium.org/2223003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4734 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These string methods can be composed from two basic blocks: charCodeAt
and fromCharCode, both of which have fast cases for certain types of
inputs. In this patch these two blocks are refactored to allow
generating the fast cases without having to jump around the slow
cases. In the slow cases since they can now be invoked both from
inline runtime functions and from IC stubs we either have to
save/restore state of the current frame or enter/leave a new internal
frame. This is handled by new RuntimeCallHelper interface. Its
implementation for virtual frame is based on FrameRegisterState class
extracted from DeferredCode class.
Review URL: http://codereview.chromium.org/2087009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4733 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1) do not push receiver early---that simplifies tail call preparation
on ia32/x64 and renders special cleanup unnecessary;
2) do not do second map check if interceptor's and cached holder
are the same;
3) do not push/pop receiver if receiver and holder registers are the same
(means that receiver is interceptor's holder);
4) do batch pushes on arm;
5) minor cosmetic improvements.
Review URL: http://codereview.chromium.org/2282001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4732 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
