* Add a sibling interface to InterpreterAssembler called
  CodeStubAssembler which provides a wrapper around the
  RawMachineAssembler and is intented to make it easy to build
  efficient cross-platform code stubs. Much of the implementation
  of CodeStubAssembler is shamelessly stolen from the
  InterpreterAssembler, and the idea is to eventually merge the
  two interfaces somehow, probably moving the
  InterpreterAssembler interface over to use the
  CodeStubAssembler. Short-term, however, the two interfaces
  shall remain decoupled to increase our velocity developing the
  two systems in parallel.
* Implement the StringLength stub in TurboFan with the new
  CodeStubAssembler. Replace and remove the old Hydrogen-stub
  version.
* Remove a whole slew of machinery to support JavaScript-style
  code stub generation, since it ultimately proved unwieldy,
  brittle and baroque. This cleanup includes removing the shared
  code stub context, several example stubs and a tangle of build
  file changes.

BUG=v8:4587
LOG=n

Review URL: https://codereview.chromium.org/1475953002

Cr-Commit-Position: refs/heads/master@{#32508}

CallIC and CallConstructStub look so alike, at least in the feedback they gather even if the implementation differs...and CallIC has such a nice way of surfacing the feedback (CallICNexus), that there is a request to make CallConstructStub look analogous. Enter ConstructICStub.

BUG=

Review URL: https://codereview.chromium.org/1476413003

Cr-Commit-Position: refs/heads/master@{#32452}

This is the initial step towards refactoring the regexp literation
creation code to make it less obscure and more similar to the mechanism
we use to create array and object literals.  There's now a new runtime
entry %CreateRegExpLiteral with the same interface as the entries for
array and object literals, except that we still pass the flags as
string.

Instead of embedding the hand written native to clone JSRegExp instances
we now have a FastCloneRegExpStub, which behaves similar to the other
FastCloneShallowArrayStub and FastCloneShallowObjectStub that we already
had.

R=mlippautz@chromium.org, yangguo@chromium.org

Review URL: https://codereview.chromium.org/1475823003

Cr-Commit-Position: refs/heads/master@{#32255}

There's no point in collecting feedback for super constructor calls,
because in all (interesting) cases we can gather (better) feedback from
other sources (i.e. via inlining or via using a LOAD_IC to get to the
[[Prototype]] of the target).  So CallConstructStub is now only used
for new Foo(...args) sites where we want to collect feedback in the
baseline compiler.  The optimizing compilers, Reflect.construct and
super constructor calls use the Construct builtin directly, which allows
us to remove some weird code from the CallConstructStub (and opens the
possibility for more code sharing with the CallICStub, maybe even going
for a ConstructICStub).

Also remove the 100% redundant HCallNew instruction, which is just a
wrapper for the Construct builtin anyway (indirectly via the
CallConstructStub).

Drive-by-fix: Drop unused has_function_cache bit on Code objects.

R=mstarzinger@chromium.org, yangguo@chromium.org
BUG=v8:4413, v8:4430
LOG=n

Review URL: https://codereview.chromium.org/1469793002

Cr-Commit-Position: refs/heads/master@{#32172}

This changes the interface descriptor for the arguments adaptor to also
contain an explicit register for the new.target value. Note that the
stub still clobbers the register for now.

This is a preparatory CL to allows us passing new.target in a register
instead of via a side-channel through the construct stub frame.

R=bmeurer@chromium.org
BUG=v8:4544
LOG=n

Review URL: https://codereview.chromium.org/1457313002

Cr-Commit-Position: refs/heads/master@{#32117}

BUG=

Review URL: https://codereview.chromium.org/1442643009

Cr-Commit-Position: refs/heads/master@{#32023}

Use %_ToLength for TO_LENGTH, implemented via a ToLengthStub
that supports a fast path for small integers. Everything else is still
handled in the runtime.

CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_nosnap_rel
BUG=v8:4494
LOG=n

Review URL: https://codereview.chromium.org/1412963002

Cr-Commit-Position: refs/heads/master@{#31358}

The stub is used for Turbofan's fast path allocation.

Review URL: https://codereview.chromium.org/1404773002

Cr-Commit-Position: refs/heads/master@{#31326}

This change add a new bytecode for operator new and implements it using
the Construct() builtin.

BUG=v8:4280
LOG=N

Committed: https://crrev.com/8e4f9963d53913eab7fbd2f61a5733d8dc2169e7
Cr-Commit-Position: refs/heads/master@{#31293}

Review URL: https://codereview.chromium.org/1402943002

Cr-Commit-Position: refs/heads/master@{#31312}

Revert of [Interpreter] Support for operator new. (patchset #17 id:290001 of https://codereview.chromium.org/1402943002/ )

Reason for revert:
[Sheriff] Breaks arm64 debug:
http://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/builds/4595

Original issue's description:
> [Interpreter] Support for operator new.
>
> This change add a new bytecode for operator new and implements it using
> the Construct() builtin.
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/8e4f9963d53913eab7fbd2f61a5733d8dc2169e7
> Cr-Commit-Position: refs/heads/master@{#31293}

TBR=rmcilroy@chromium.org,bmeurer@chromium.org,oth@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280

Review URL: https://codereview.chromium.org/1402153004

Cr-Commit-Position: refs/heads/master@{#31298}

This change add a new bytecode for operator new and implements it using
the Construct() builtin.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1402943002

Cr-Commit-Position: refs/heads/master@{#31293}

The stack manipulation was expensive. Two virtual registers are better.

BUG=

Review URL: https://codereview.chromium.org/1376933006

Cr-Commit-Position: refs/heads/master@{#31204}

Adds support for calling runtime functions from the interpreter. Adds the
CallRuntime bytecode which takes a Runtime::FunctionId of the function to call
and the arguments in sequential registers. Adds a InterpreterCEntry builtin
to enable the interpreter to enter C++ code based on the functionId.

Also renames Builtin::PushArgsAndCall to Builtin::InterpreterPushArgsAndCall
and groups all the interpreter builtins together.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1362383002

Cr-Commit-Position: refs/heads/master@{#31089}

Revert of [Interpreter] Add CallRuntime support to the interpreter. (patchset #8 id:220001 of https://codereview.chromium.org/1362383002/ )

Reason for revert:
Now breaking arm32 debug bot (worked locally even with --debug-code, so I'll need to figure out what's different on the bot)

Original issue's description:
> [Interpreter] Add CallRuntime support to the interpreter.
>
> Adds support for calling runtime functions from the interpreter. Adds the
> CallRuntime bytecode which takes a Runtime::FunctionId of the function to call
> and the arguments in sequential registers. Adds a InterpreterCEntry builtin
> to enable the interpreter to enter C++ code based on the functionId.
>
> Also renames Builtin::PushArgsAndCall to Builtin::InterpreterPushArgsAndCall
> and groups all the interpreter builtins together.
>
> BUG=v8:4280
> LOG=N
>

TBR=bmeurer@chromium.org,oth@chromium.org,mstarzinger@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280

Review URL: https://codereview.chromium.org/1379933003

Cr-Commit-Position: refs/heads/master@{#31078}

Adds support for calling runtime functions from the interpreter. Adds the
CallRuntime bytecode which takes a Runtime::FunctionId of the function to call
and the arguments in sequential registers. Adds a InterpreterCEntry builtin
to enable the interpreter to enter C++ code based on the functionId.

Also renames Builtin::PushArgsAndCall to Builtin::InterpreterPushArgsAndCall
and groups all the interpreter builtins together.

BUG=v8:4280
LOG=N

Committed: https://crrev.com/40e8424b744f8b6e3e1d93e20f23487419911dfc
Cr-Commit-Position: refs/heads/master@{#31064}

Review URL: https://codereview.chromium.org/1362383002

Cr-Commit-Position: refs/heads/master@{#31076}

Revert of [Interpreter] Add CallRuntime support to the interpreter. (patchset #6 id:180001 of https://codereview.chromium.org/1362383002/ )

Reason for revert:
Broke Arm64 bot (CEntry stub is trying to pop arguments off stack when argv_in_reg, so I need to fix this).

Original issue's description:
> [Interpreter] Add CallRuntime support to the interpreter.
>
> Adds support for calling runtime functions from the interpreter. Adds the
> CallRuntime bytecode which takes a Runtime::FunctionId of the function to call
> and the arguments in sequential registers. Adds a InterpreterCEntry builtin
> to enable the interpreter to enter C++ code based on the functionId.
>
> Also renames Builtin::PushArgsAndCall to Builtin::InterpreterPushArgsAndCall
> and groups all the interpreter builtins together.
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/40e8424b744f8b6e3e1d93e20f23487419911dfc
> Cr-Commit-Position: refs/heads/master@{#31064}

TBR=bmeurer@chromium.org,oth@chromium.org,mstarzinger@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280

Review URL: https://codereview.chromium.org/1387543002

Cr-Commit-Position: refs/heads/master@{#31066}

Adds support for calling runtime functions from the interpreter. Adds the
CallRuntime bytecode which takes a Runtime::FunctionId of the function to call
and the arguments in sequential registers. Adds a InterpreterCEntry builtin
to enable the interpreter to enter C++ code based on the functionId.

Also renames Builtin::PushArgsAndCall to Builtin::InterpreterPushArgsAndCall
and groups all the interpreter builtins together.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1362383002

Cr-Commit-Position: refs/heads/master@{#31064}

This lowers JSCreateArgument nodes to call the ArgumentsAccessStub for
help with materializing arguments objects when possible. Along the way
this changes the calling convention of said stub to take parameters in
registers instead of on the stack.

R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/1348773002

Cr-Commit-Position: refs/heads/master@{#30919}

The StringCompareStub used to take its parameters on the (JavaScript)
stack, which made it impossible to use in TurboFan. Actually
StringCompareStub was currently completely unused. This changes the
calling convention to something TurboFan compatible and introduces a
CallInterfaceDescriptor for StringCompareStub. It also changes
HStringCompareAndBranch to use the StringCompareStub instead of using
the full blown CompareICStub for a stupid string comparison.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/1347913003

Cr-Commit-Position: refs/heads/master@{#30818}

Adds support for JS calls to the interpreter. In order to support
calls from the interpreter, the PushArgsAndCall builtin is added
which pushes a sequence of arguments onto the stack and calls
builtin::Call.

Adds the Call bytecode.

MIPS port contributed by akos.palfi@imgtec.com in https://codereview.chromium.org/1334873002/

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1323463005

Cr-Commit-Position: refs/heads/master@{#30710}

The semantics of the %_CallFunction intrinsic seem to be very unclear,
which resulted in a lot of bugs. Especially the combination with
%IsSloppyModeFunction is always a bug, because the receiver would be
wrapped in the wrong context. So the %IsSloppyModeFunction helper is
gone now, and many of the buggy uses of %_CallFunction are also
eliminated.

If you ever need to call something with a different receiver, then
%_Call is your friend now. It does what you want and implements the
call sequence fully (and correct).

BUG=v8:4413
LOG=n

Review URL: https://codereview.chromium.org/1325573004

Cr-Commit-Position: refs/heads/master@{#30634}

This adds a new ToString runtime function and a fast-path ToStringStub
(which is just a simple dispatcher for existing functionality), and also
implements %_ToName using the ToStringStub.

R=mstarzinger@chromium.org, yangguo@chromium.org
BUG=v8:4307
LOG=n

Review URL: https://codereview.chromium.org/1319973007

Cr-Commit-Position: refs/heads/master@{#30442}

The previous hack with HInstanceOfKnownGlobal was not only slower,
but also very brittle and required a lot of weird hacks to support it. And
what's even more important it wasn't even correct (because a map check
on the lhs is never enough for instanceof).

The new implementation provides a sane runtime implementation
for InstanceOf plus a fast case in the InstanceOfStub, combined with
a proper specialization in the case of a known global in CrankShaft,
which does only the prototype chain walk (coupled with a code
dependency on the known global).

As a drive-by-fix: Also fix the incorrect Object.prototype.isPrototypeOf
implementation.

BUG=v8:4376
LOG=y

Review URL: https://codereview.chromium.org/1304633002

Cr-Commit-Position: refs/heads/master@{#30342}

BUG=

Review URL: https://codereview.chromium.org/1292173003

Cr-Commit-Position: refs/heads/master@{#30284}

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1299563003

Cr-Commit-Position: refs/heads/master@{#30187}

This is the initial (big) step towards a more uniform implementation of
the ToObject abstract operation (ES6 7.1.13), where we have a fallback
implementation in JSReceiver::ToObject() and a fast (hydrogen) CodeStub
to deal with the fast case (we should be able to do more cleanup on this
in a followup CL).  For natives we expose the abstract operation via a
%_ToObject intrinsic, also exposed via a macro TO_OBJECT, that unifies
the previous confusion with TO_OBJECT_INLINE, ToObject, TO_OBJECT,
$toObject and %$toObject.  Now the whole implementation of the abstract
operation is context independent, meaning we don't need any magic in the
builtins object nor the native context.

R=mvstanton@chromium.org,yangguo@chromium.org

Review URL: https://codereview.chromium.org/1266013006

Cr-Commit-Position: refs/heads/master@{#29953}

No need to pass the name explicitly to the stubs; the runtime can
extract the name from the ScopeInfo (the extension of the
ScriptContext) on-demand easily without any performance impact.

Review URL: https://codereview.chromium.org/1259963002

Cr-Commit-Position: refs/heads/master@{#29886}

This is the initial round of optimizations for the
LoadGlobalViaContextStub and StoreGlobalViaContextStub, basically
turning them into platform code stubs to avoid the Crankshaft overhead
in the fast case, and making the runtime interface cheaper.

R=ishell@chromium.org
BUG=chromium:510694
LOG=n

Review URL: https://codereview.chromium.org/1238143002

Cr-Commit-Position: refs/heads/master@{#29834}

All of this is controlled by the CallDescriptor. It's simply the case
that if you specify less registers than the function arity calls for,
the rest are assumed to be on the stack.

Bailout handlers accept these constant stack arguments too.

BUG=

Review URL: https://codereview.chromium.org/1250563004

Cr-Commit-Position: refs/heads/master@{#29813}

It's just the same as StoreTransitionDescriptor.

BUG=

Review URL: https://codereview.chromium.org/1248973002

Cr-Commit-Position: refs/heads/master@{#29789}

This changes the calling convention of the CallConstructStub to take
the original constructor (i.e. new.target in JS-speak) in a register
instead of magically via the operand stack. For optimizing compilers
the operand stack doesn't exist, hence cannot be peeked into.

R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/1237813002

Cr-Commit-Position: refs/heads/master@{#29681}

Loads and stores to global vars are now made via property cell shortcuts installed into parent script context.

This CL also adds hydrogen stubs for global loads and global stores, full-codegen and TurboFan now uses this machinery.

Review URL: https://codereview.chromium.org/1224793002

Cr-Commit-Position: refs/heads/master@{#29592}

- Add a TurboFanIC class, derived from TurboFanCodeStub, that
  automatically distinguishes between versions of the IC called from
  optimized and unoptimized code.
- Add appropriate InterfaceDescriptors for both the versions of the
  stub called from unoptimized and optimized code
- Change the MathFloor TF stub generator to output either the
  for-optimized or for-unoptimized version based on the minor_key
  parameter.

Committed: https://crrev.com/8f13b655b8a10dae2116dd18b32f09337bb2d410
Cr-Commit-Position: refs/heads/master@{#29534}

Review URL: https://codereview.chromium.org/1225943002

Cr-Commit-Position: refs/heads/master@{#29539}

Revert of Add unoptimized/optimized variants of MathFloor TF code stub (patchset #4 id:60001 of https://codereview.chromium.org/1225943002/)

Reason for revert:
Failure on compiling runtime.js on windows

Original issue's description:
> Add unoptimized/optimized variants of MathFloor TF code stub
>
> - Add a TurboFanIC class, derived from TurboFanCodeStub, that
>   automatically distinguishes between versions of the IC called from
>   optimized and unoptimized code.
> - Add appropriate InterfaceDescriptors for both the versions of the
>   stub called from unoptimized and optimized code
> - Change the MathFloor TF stub generator to output either the
>   for-optimized or for-unoptimized version based on the minor_key
>   parameter.
>
> Committed: https://crrev.com/8f13b655b8a10dae2116dd18b32f09337bb2d410
> Cr-Commit-Position: refs/heads/master@{#29534}

TBR=mvstanton@chromium.org,bmeurer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1220783006

Cr-Commit-Position: refs/heads/master@{#29535}

- Add a TurboFanIC class, derived from TurboFanCodeStub, that
  automatically distinguishes between versions of the IC called from
  optimized and unoptimized code.
- Add appropriate InterfaceDescriptors for both the versions of the
  stub called from unoptimized and optimized code
- Change the MathFloor TF stub generator to output either the
  for-optimized or for-unoptimized version based on the minor_key
  parameter.

Review URL: https://codereview.chromium.org/1225943002

Cr-Commit-Position: refs/heads/master@{#29534}

Up until now the context register was listed explicitly in each stub's
CallInterfaceDescriptor. This was problematic, because it was listed
first in the list of register parameters--which is fine for Crankshaft,
which is more or less built to handle the context as the first
parameter-- but not ideal for TurboFan, which adds the context at
the end of all function parameters. Now the context register is no
longer in the register list and can be handled appropriately by both
compilers. Specifically, this allows the FunctionType specified for
each CallInterfaceDescriptor to exactly match the parameter register
list.

Review URL: https://codereview.chromium.org/1211333003

Cr-Commit-Position: refs/heads/master@{#29402}

- Thread Type::FunctionType through stubs and the TF pipeline.
- Augment Typer to decorate parameter nodes with types from
  a Type::FunctionType associated with interface descriptors.
- Factor interface descriptors into platform-specific and
  platform-independent components so that all descriptors share
  a common Type::FunctionType for all platforms.

Review URL: https://codereview.chromium.org/1197703002

Cr-Commit-Position: refs/heads/master@{#29248}

When compiling on a laptop I like to concatenate the small test files.
This makes a big difference to compile times. These changes make that
easier.

R=ulan@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1163803002

Cr-Commit-Position: refs/heads/master@{#28742}

Also introduce new interface descriptors for the trampoline and full
versions of those stubs.

Currently, the stubs aren't functional.

BUG=

Review URL: https://codereview.chromium.org/1149903005

Cr-Commit-Position: refs/heads/master@{#28597}

Also removed ornamentation like "VectorRaw" from stub names.

BUG=

Review URL: https://codereview.chromium.org/1144063002

Cr-Commit-Position: refs/heads/master@{#28516}