This change encompasses what is necessary to enable stack checks in loops without suffering large regressions.
Primarily, it consists of a new mechanism for dealing with deferred blocks by "splintering", rather than splitting, inside deferred blocks.
My initial change was splitting along deferred block boundaries, but the regression introduced by stackchecks wasn't resolved conclusively. After investigation, it appears that just splitting ranges along cold block boundaries leads to a greater opportunity for moves on the hot path, hence the suboptimal outcome.
The alternative "splinters" ranges rather than splitting them. While splitting creates 2 ranges and links them (parent-child), in contrast, splintering creates a new independent range with no parent-child relation to the original. The original range appears as if it has a liveness hole in the place of the splintered one. All thus obtained ranges are then register allocated with no change to the register allocator.
The splinters (cold blocks) do not conflict with the hot path ranges, by construction. The hot path ones have less pressure to split, because we remove a source of conflicts. After allocation, we merge the splinters back to their original ranges and continue the pipeline. We leverage the previous changes made for deferred blocks (determining where to spill, for example).
Review URL: https://codereview.chromium.org/1305393003
Cr-Commit-Position: refs/heads/master@{#30357}
Adds implementations and tests for the following bytecodes:
- Add
- Sub
- Mul
- Div
- Mod
Also adds the Mod bytecode and adds support to BytecodeGenerator and
BytecodeArrayBuilder to enable it's use.
The current bytecodes always call through to the JS builtins. This also adds
LoadObjectField and CallJSBuiltin operators to the InterpreterAssembler.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1300813005
Cr-Commit-Position: refs/heads/master@{#30352}
Passes the current context to bytecode interpreter handlers. This is held in the
context register on all architectures except for ia32 where there are too few
registers and it is instead spilled to the stack.
Also changes Load/StoreRegister to use kMachAnyTagged representation since they
should only ever hold tagged values.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1294133004
Cr-Commit-Position: refs/heads/master@{#30325}
Makes the following modifications to the interpreter builtins and
InterpreterAssembler:
- Adds an accumulator register and initializes it to undefined()
- Adds a register file pointer register and use it instead of FramePointer to
access registers
- Modifies builtin to support functions with 0 regiters in the register file
- Modifies builtin to Call rather than TailCall to first bytecode handler.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1289863003
Cr-Commit-Position: refs/heads/master@{#30219}
- Make the API look like v8::V8::InitializeICU.
(That is: A static method call, not an object to be created on the stack.)
- Fix path separator on Windows, by calling base::OS::isPathSeparator.
- Move into API, so that it can be called by hello-world & friends.
- Actually call it from hello-world and friends.
R=jochen@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1292053002
Cr-Commit-Position: refs/heads/master@{#30174}
Reason for revert:
Breaks win32 nosnap
Original issue's description:
> [runtime] Remove useless IN builtin.
>
> Similar to DELETE, the IN builtin is just a thin wrapper for %HasElement
> and %HasProperty anyway, and cannot be optimized, plus it had a weird
> special fast case (which also involved at least one LOAD_IC plus some
> intrinsic magic).
>
> R=yangguo@chromium.org,jarin@chromium.org
>
> Committed: https://crrev.com/72d60a1e80e81e2e68ca402665e2acbc46c5e471
> Cr-Commit-Position: refs/heads/master@{#30154}
TBR=yangguo@chromium.org,jarin@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review URL: https://codereview.chromium.org/1288923002
Cr-Commit-Position: refs/heads/master@{#30155}
Similar to DELETE, the IN builtin is just a thin wrapper for %HasElement
and %HasProperty anyway, and cannot be optimized, plus it had a weird
special fast case (which also involved at least one LOAD_IC plus some
intrinsic magic).
R=yangguo@chromium.org,jarin@chromium.org
Review URL: https://codereview.chromium.org/1295433002
Cr-Commit-Position: refs/heads/master@{#30154}
Modifies the BytecodeArrayBuilder to create register operands which are
negative. This reduces the number of instructions to access registers
by the interpreter and allows us to use positive register operands to
access parameter values.
Adds a Register class to keep register usage typesafe and simplify the
convertion to bytecode operand values.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1283313003
Cr-Commit-Position: refs/heads/master@{#30151}
TurboFan is now a requirement and supported by all backends, so we don't
need those macros (plus all the machinery on top) anymore.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1282763002
Cr-Commit-Position: refs/heads/master@{#30082}
Rationale: The {kind} of a call descriptor describes what the {target} being
called is--i.e. a JSFunction, code object, or address. That kind materially
dictates the instruction(s) generated for an outgoing call.
The other flags on a call descriptor should describe specific properties
(like whether a roots register is valid or not) so that backend logic doesn't
have to switch over the kind, but is informed directly of what it wants to
know.
R=mstarzinger@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1268273003
Cr-Commit-Position: refs/heads/master@{#30065}
Add factory methods for different types of LinkageLocations, and ensure that
accesses to the underlying data in the location are classified by type and
funneled through explicit accessors.
Also change the representation of LinkageLocation to use a BitField rather
than using a reserved section of the integer range.
Review URL: https://codereview.chromium.org/1262343002
Cr-Commit-Position: refs/heads/master@{#29938}
Adds interpreter entry and exit trampoline builtins. Also implements the
Return bytecode handler and fixes a few bugs in InterpreterAssembler
highlighted by running on other architectures.
MIPS and MIPS64 port contributed by Paul Lind (paul.lind@imgtec.com)
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1245133002
Cr-Commit-Position: refs/heads/master@{#29929}
Changes the interpreter to use a BytecodeArray pointer and an offset to avoid
having an inner pointer to a BytecodeArray object in registers during dispatch.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1254293006
Cr-Commit-Position: refs/heads/master@{#29910}
Adds basic support for generation of interpreter bytecode handler code
snippets. The InterpreterAssembler class exposes a set of low level,
interpreter specific operations which can be used to build a Turbofan
graph. The Interpreter class generates a bytecode handler snippet for
each bytecode by assembling operations using an InterpreterAssembler.
Currently only two simple bytecodes are supported: LoadLiteral0 and Return.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1239793002
Cr-Commit-Position: refs/heads/master@{#29814}
Consolidated conflict detection and traversal logic in CoalescedLiveRanges to avoid duplication in both code and testing. In addition, this change achieves better separation between CoalescedLiveRanges and other register allocator components, improving testability and maintainability.
BUG=
Review URL: https://codereview.chromium.org/1219063017
Cr-Commit-Position: refs/heads/master@{#29783}
The InterpreterAssembler needs to specify a specific CallDescriptor type
instead of using the SimplifiedCDescriptor type. This CL makes it possible
to specify the CallDescriptor used by the RawMachineAssembler instead of
specifying a MachineSignature.
Also removes instruction-selector-tester.h which was erroneously resurrected
at some point.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1235313002
Cr-Commit-Position: refs/heads/master@{#29777}
In many cases, the context that TurboFan's ASTGraphBuilder or subsequent
reduction operations attaches to nodes does not need to be that exact
context, but rather only needs to be one with the same native context,
because it is used internally only to fetch the native context, e.g. for
creating and throwing exceptions.
This reducer recognizes common cases where the context that is specified
for a node can be relaxed to a canonical, less specific one. This
relaxed context can either be the enclosing function's context or a specific
Module or Script context that is explicitly created within the function.
This optimization is especially important for TurboFan-generated code stubs
which use context specialization and inlining to generate optimal code.
Without context relaxation, many extraneous moves are generated to pass
exactly the right context to internal functions like ToNumber and
AllocateHeapNumber, which only need the native context. By turning context
relaxation on, these moves disappear because all these common internal
context uses are unified to the context passed into the stub function, which
is typically already in the correct context register and remains there for
short stubs. It also eliminates the explicit use of a specialized context
constant in the code stub in these cases, which could cause memory leaks.
Review URL: https://codereview.chromium.org/1244583003
Cr-Commit-Position: refs/heads/master@{#29763}
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}
Reduce Float64 comparison to Float32 when both inputs are conversions from
Float32.
Review URL: https://codereview.chromium.org/1235663002
Cr-Commit-Position: refs/heads/master@{#29586}
Optimize string "length" property access based on static type
information if possible, but also optimistically optimize the access
based on type feedback from the LoadIC.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1216593003
Cr-Commit-Position: refs/heads/master@{#29543}
We actually need round to zero truncation to implement the counterpart
of LDoubleToI in TurboFan, which tries to convert a double to an integer
as required for keyed load/store optimizations.
Drive-by-cleanup: Reduce some code duplication in the InstructionSelector
implementations.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1225993002
Cr-Commit-Position: refs/heads/master@{#29527}
The RawMachineAssembler will be used to build the interpreter, so it needs
to move back to src/compiler.
This reverts commit b5b00cc031.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1221303014
Cr-Commit-Position: refs/heads/master@{#29519}
Currently we lower shifts directly to machine operators, and add an
appropriate Word32And to implement the & 0x1F operation on the right
hand side required by the specification. However for Word32And we assume
Int32 in simplified lowering, which is basically changes the right hand
side bit interpretation for the shifts from Uint32 to Int32, which is
obviously wrong. So now we represent that explicitly by proper
simplified operators for the shifts, which are lowered to machine in
simplified lowering.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1213803008
Cr-Commit-Position: refs/heads/master@{#29465}
Support 32-bit cmp with shift/extend by reusing the existing add/sub shift and
extend code.
Review URL: https://codereview.chromium.org/1218103005
Cr-Commit-Position: refs/heads/master@{#29435}
Revert "Revert relanded strong property access CL"
Regression issues should be solved. Initial patchset is the original, subsequent patchsets are the fixing modifications.
This reverts commit 4ac7be5656.
BUG=v8:3956
LOG=N
Review URL: https://codereview.chromium.org/1199983002
Cr-Commit-Position: refs/heads/master@{#29384}
Move the arithmetic shift from Int32MulHigh to a following Int32Add on ARM64.
This graph is commonly generated on reduction of signed integer division.
Review URL: https://codereview.chromium.org/1209413008
Cr-Commit-Position: refs/heads/master@{#29380}
