[turbofan] Transform x * -1.0 to -0.0 - x.

TEST=msjunit/asm,unittests
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/683753004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25176 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
MIPS: Skip embenchen tests on big-endian.

Emscripten requires little-endian arch. It has assertion for endianness:

assert(HEAPU8[0] === 255 && HEAPU8[3] === 0,
    'Typed arrays 2 must be run on a little-endian system');

TEST=mjsunit/asm/embenchen/*
BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/708663003

Patch from Paul Lind <paul.lind@imgtec.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25177 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] extend register allocator testing with control flow

R=bmeurer@chromium.org, jarin@chromium.org

BUG=

Review URL: https://codereview.chromium.org/699083003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25178 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Retry: Parser & internalization fix: ensure no heap allocs during GetString(Handle<String>).

The bug has always been there: when the parser is operating in the "immediately
internalize" mode and calls GetString, we get FlatContent of a string and then
do heap allocation.

The bug was uncovered by https://codereview.chromium.org/693803004/ (which put
the parser to the "immediately internalize" mode more often), but looking at the
code, it's possible that it can happen in other cases too.

This CL makes AstValueFactory handle this situation gracefully: it won't try to
internalize inside GetString(Handle<String>); it's unnecessary anyway since we
have the Handle<String> already.

BUG=
R=rossberg@chromium.org

Review URL: https://codereview.chromium.org/706533005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25179 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] Turn various diamonds into selects.

TEST=cctest/test-changes-lowering,mjsunit/asm,unittests
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/704463004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25180 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Avoid redundant work in scheduler loop header/depth calculation.

R=jarin@chromium.org

TEST=cctest/test-scheduler/LoopedFloatingDiamond2

Review URL: https://codereview.chromium.org/702683002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25181 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The idea behind of this solution is to use the existing "relocation info" instead of consumption the CodeLinePosition events emitted by the V8 compilers.
During generation code and relocation info are generated simultaneously.
When code generation is done you each code object has associated "relocation info".
Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
correspondences between the machine program counter and source locations for stack walking.

This patch:
1. Add more source positions info in reloc info to make it suitable for source level mapping.
The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
(2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).

2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
If a source line is found that hit counter is increased by one for this line.

3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.

4.Add a test that checks how the samples are distributed through source lines.
It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.

Patch from Denis Pravdin <denis.pravdin@intel.com>;

R=svenpanne@chromium.org, yurys@chromium.org

Review URL: https://codereview.chromium.org/682143003

Patch from Weiliang <weiliang.lin@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25182 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Skip tests that timeout on arm64

TBR=machenbach@chromium.org

Review URL: https://codereview.chromium.org/709443002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25183 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reuse RPO traversal stack in the scheduler.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/695303003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25184 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix for an assertion failure in Map::FindTransitionToField(...). Appeared after r25136.

BUG=chromium:430846
LOG=N
R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/704183002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25185 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Skip json2 on 64 bits debug.

BUG=3681
LOG=n
TBR=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/701353003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25186 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Turn ToNumberStub into a PlatformCodeStub again.

The HydrogenCodeStub is too expensive and there's no easy way to reduce
this cost, so turning it into a PlatformCodeStub solves that problem
until we can use TurboFan for code stubs.

TEST=mjsunit
R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/683913008

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25187 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Remove workaround for successors on end block from scheduler.

R=titzer@chromium.org
TEST=cctest/test-scheduler/RPOLoop

Review URL: https://codereview.chromium.org/708763002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25188 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] Push TruncateFloat64ToInt32 into phis.

TEST=unittests
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/707683003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25189 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Allow JSArray fast moving elements even if the array's proto isn't Array.prototype in original state
Otherwise array builtins don't work on internal arrays.

BUG=v8:3681
LOG=n
R=machenbach@chromium.org, mvstanton@chromium.org

Review URL: https://codereview.chromium.org/706703005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25190 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] phis cannot take registers as inputs

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/704153002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25191 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix marking time in cumulative gc stats.

BUG=
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/708483004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25192 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] (reland) Compute tighter ranges for modulus in Typer.

R=jarin@chromium.org
BUG=

Review URL: https://codereview.chromium.org/694703004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25193 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Revert "Remove workaround for successors on end block from scheduler."

TBR=titzer@chromium.org

Review URL: https://codereview.chromium.org/705043002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25194 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] Combine JSToNumber and ChangeTaggedToFloat64 for fast SMI case.

This does the following optimization during ChangeLowering:

 ChangeTaggedToFloat64(JSToNumber(x)) =>
   if IsSmi(x) then ChangeSmiToFloat64(x)
   else let y = JSToNumber(x) in
     if IsSmi(y) then ChangeSmiToFloat64(y)
     else LoadHeapNumberValue(y)

Also cleanup/rearrange some code duplication in ChangeLowering.

R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/703103003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25195 ce2b1a6d-e550-0410-aec6-3dcde31c8c00