MachineType is now a class with two enum fields:
- MachineRepresentation
- MachineSemantic

Both enums are usable on their own, and this change switches some places from using MachineType to use just MachineRepresentation. Most notably:
- register allocator now uses just the representation.
- Phi and Select nodes only refer to representations.

Review URL: https://codereview.chromium.org/1513543003

Cr-Commit-Position: refs/heads/master@{#32738}

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

Review URL: https://codereview.chromium.org/1498833002

Cr-Commit-Position: refs/heads/master@{#32564}

Reland: [turbofan] Various fixes to allow unboxed doubles as arguments in registers and on the stack.

OCL: https://codereview.chromium.org/1263033004/

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1284893002

Cr-Commit-Position: refs/heads/master@{#30115}

Revert of [turbofan] Various fixes to allow unboxed doubles as arguments in registers and on the stack. (patchset #7 id:120001 of https://codereview.chromium.org/1263033004/ )

Reason for revert:
This CL breaks MIPS (roll blocker).

https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20mipsel%20-%20sim/builds/2061/steps/Check/logs/Run_Int32_Select_1

Original issue's description:
> [turbofan] Various fixes to allow unboxed doubles as arguments in registers and on the stack.
>
> R=jarin@chromium.org
> BUG=
>
> Committed: https://crrev.com/71409be5395f867bbca0f6998bf6caa175cd8192
> Cr-Commit-Position: refs/heads/master@{#30091}

TBR=jarin@chromium.org,titzer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/1284853002

Cr-Commit-Position: refs/heads/master@{#30101}

R=jarin@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1263033004

Cr-Commit-Position: refs/heads/master@{#30091}

This fixes a few funky implicit conversions for the enum (that are
inconsistent across compilers) and also helps to save space, i.e. for
the representations_ vector in the InstructionSequence.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/1182303003

Cr-Commit-Position: refs/heads/master@{#29011}

Tail calls are matched on the graph, with a dedicated tail call
optimization that is actually testable. The instruction selection can
still fall back to a regular if the platform constraints don't allow to
emit a tail call (i.e. the return locations of caller and callee differ
or the callee takes non-register parameters, which is a restriction that
will be removed in the future).

Also explicitly limit tail call optimization to stubs for now and drop
the global flag.

BUG=v8:4076
LOG=n

Review URL: https://codereview.chromium.org/1114163005

Cr-Commit-Position: refs/heads/master@{#28219}

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1118823003

Cr-Commit-Position: refs/heads/master@{#28191}

Also remove the LEA matching from x64, since it was never really
effective. We'll optimize that once we're correct.

TEST=cctest,unittests
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/652363006

Cr-Commit-Position: refs/heads/master@{#25024}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25024 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=mjsunit,unittests
R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/691513002

Cr-Commit-Position: refs/heads/master@{#24980}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24980 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This change enables non-tagged representations in FrameStates.

That allows us to run zlib with deoptimization support and have almost the same performance of the generated code (as the code with no deoptimization). Unfortunately, the frame states seem to confuse typer. As a consequence, we generate more representation changes, which in turn causes the scheduler to take a lot more time and memory (>4x). The added compiler time makes zlib with deopt be about 50% slower.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/614713002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24454 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Review URL: https://codereview.chromium.org/618643002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24319 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=compiler-unittests,cctest
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/547233003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23864 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This simplifies the handling of MachineTypes for parameters and returns
used in tests, and overall improves the regularity with which they
are handled in both tests and in CallDescriptor.

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

Review URL: https://codereview.chromium.org/530783002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23638 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=base-unittests,cctest,mjsunit
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/528993002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23617 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Add MachineSignature, which is an encapsulation of the machine types for parameters and return values in a graph.

This utility will be used to simplify Linkage and fix representation inference
to work with graphs where parameters and return values are something other
than tagged. It will also make testing representation inference a lot
easier, since we can then exactly nail down the machine types of parameters
and returns.

This CL also adds c-signature.h, which demonstrates how to convert C function
signatures into MachineSignatures. The CSignatures will be used in tests to
make it easier and simpler to codegen tests.

R=jarin@chromium.org
BUG=

Review URL: https://codereview.chromium.org/515173002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23490 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

This is the bare minimum required to support typed arrays. Support for
working with float32 values will be added based on this.

TEST=compiler-unittests,cctest
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/500343002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23386 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Also rename the arch opcodes to match their native counterparts.

TEST=compiler-unittests,cctest
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/505713002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23345 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

MachineType now tracks both the representation and the value type of machine quantities and is used uniformly throughout TurboFan.

These types can now express uint8, int8, uint16, and int16, i.e. signed and unsigned smallish integers. Note that currently only uint8 and uint16 are implemented in the TF backends.

R=bmeurer@chromium.org, mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/470593002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23122 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Move MachineRepresentation to machine-type.h and rename to MachineType in preparation for merging it with RepType.

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/456333002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23051 ce2b1a6d-e550-0410-aec6-3dcde31c8c00