These JavaScript operators were special hacks to ensure that we always
operate on Smis for the magic for-in index variable, but this never
really worked in the OSR case, because the OsrValue for the index
variable didn't have the proper information (that we have for the
JSForInPrepare in the non-OSR case).
Now that we have loop induction variable analysis and binary operation
hints, we can just use JSLessThan and JSAdd instead with appropriate
Smi hints, which handle the OSR case by inserting Smi checks (that are
always true). Thanks to OSR deconstruction and loop peeling these Smi
checks will be hoisted so they don't hurt the OSR case too much.
Drive-by-change: Rename the ForInDone bytecode to ForInContinue, since
we have to lower it to JSLessThan to get the loop induction variable
goodness.
R=epertoso@chromium.org
BUG=v8:5267
Review-Url: https://codereview.chromium.org/2289613002
Cr-Commit-Position: refs/heads/master@{#38968}
Removes all accesses to the Isolate during bytecode generation and the
bytecode pipeline. Adds an DisallowIsolateAccessScope which is used to
enforce this invariant within the BytecodeGenerator.
BUG=v8:5203
Review-Url: https://codereview.chromium.org/2242193002
Cr-Commit-Position: refs/heads/master@{#38716}
Now that all backends use the source position builder to record source
positions, simplify the code line logging events to take a source
position table on code creation. This means that the source position
table builder no longer needs to access the isolate until the table is
generated. This is required for off-thread bytecode generation.
BUG=v8:5203
Review-Url: https://codereview.chromium.org/2248673002
Cr-Commit-Position: refs/heads/master@{#38676}
This gets rid of the Star bytecodes that were always dispatched to from
ToObject.
ToObject now outputs to register instead of to the accumulator and
ForInPrepare gets the receiver object from an input register.
BUG=v8:4820
LOG=n
Review-Url: https://codereview.chromium.org/2189463006
Cr-Commit-Position: refs/heads/master@{#38177}
Add explicit state in BytecodeSourceInfo to simplify checks for
validity and whether a statement or expression position.
Remove BytecodeSourceInfo::Update which inherited rules for updating
source position information during bytecode building.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2048203002
Cr-Commit-Position: refs/heads/master@{#37136}
This moves processing of jumps out of bytecode array builder and into
bytecode array writer. This simplifies the pipeline by avoiding having
to flush for offset and patch up offsets in bytecode array builder based
on what was emitted by the bytecode array writer.
This also enables future refactorings to add dead code elimination back
into the pipeline, and move processing of scalable operand sizes to the
end of the pipeline (in the bytecode array writer) rather than having to
deal with scalable operand types throughout pipeline.
BUG=v8:4280,chromium:616064
Review-Url: https://codereview.chromium.org/2035813002
Cr-Commit-Position: refs/heads/master@{#36716}
This change introduces a pipeline for the final stages of
bytecode generation.
The peephole optimizer is made distinct from the BytecodeArrayBuilder.
A new BytecodeArrayWriter is responsible for writing bytecode. It
also keeps track of the maximum register seen and offers a potentially
smaller frame size.
R=rmcilroy@chromium.org
LOG=N
BUG=v8:4280
Review-Url: https://codereview.chromium.org/1947403002
Cr-Commit-Position: refs/heads/master@{#36220}
