Adds back simple dead code elimination to the bytecode pipeline.
BUG=v8:4280,chromium:616064
Review-Url: https://codereview.chromium.org/2038083002
Cr-Commit-Position: refs/heads/master@{#37147}
With this change the bytecode array builder only emits expression
positions for bytecodes that can throw. This allows more peephole
optimization opportunities and results in smaller code.
BUG=v8:4280,chromium:615979
LOG=N
Review-Url: https://codereview.chromium.org/2038323002
Cr-Commit-Position: refs/heads/master@{#36863}
Eliminating dead code in the bytecode array builder doesn't play nice
with the register elimination optimizer. We should move it to it's own
stage in the optimization pipeline, however doing so would require
refactoring of how we deal with jumps, so for now just remove the dead
code elimination optimization.
BUG=chromium:616064
Review-Url: https://codereview.chromium.org/2030583002
Cr-Commit-Position: refs/heads/master@{#36660}
Prints source position information alongside bytecode.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/1963663002
Cr-Commit-Position: refs/heads/master@{#36171}
This change introduces wide prefix bytecodes to support wide (16-bit)
and extra-wide (32-bit) operands. It retires the previous
wide-bytecodes and reduces the number of operand types.
Operands are now either scalable or fixed size. Scalable operands
increase in width when a bytecode is prefixed with wide or extra-wide.
The bytecode handler table is extended to 256*3 entries. The
first 256 entries are used for bytecodes with 8-bit operands,
the second 256 entries are used for bytecodes with operands that
scale to 16-bits, and the third group of 256 entries are used for
bytecodes with operands that scale to 32-bits.
LOG=N
BUG=v8:4747,v8:4280
Review URL: https://codereview.chromium.org/1783483002
Cr-Commit-Position: refs/heads/master@{#34955}
We need to pop the context to correct level on return as well. This was incorrectly
removed in this cl: https://codereview.chromium.org/1768123002/. For example
when we have a try-catch-finally block and catch does a return, the return
does not happen immediately. It should execute finally block before it
returns. Return statement should pop the context to the correct level as
expected by finally block.
BUG=594369,v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1796893002
Cr-Commit-Position: refs/heads/master@{#34822}
The current implementation does not consider the case when the context of
the control scope and the current context differ. It is possible that they are
different in some cases for example: with statements. This cl fixes this.
BUG=v8:4280,v8:4680
LOG=N
Review URL: https://codereview.chromium.org/1768123002
Cr-Commit-Position: refs/heads/master@{#34609}
Bytecode expectations have been moved to external (.golden) files,
one per test. Each test in the suite builds a representation of the
the compiled bytecode using BytecodeExpectationsPrinter. The output is
then compared to the golden file. If the comparision fails, a textual
diff can be used to identify the discrepancies.
Only the test snippets are left in the cc file, which also allows to
make it more compact and meaningful. Leaving the snippets in the cc
file was a deliberate choice to allow keeping the "truth" about the
tests in the cc file, which will rarely change, as opposed to golden
files.
Golden files can be generated and kept up to date using
generate-bytecode-expectations, which also means that the test suite
can be batch updated whenever the bytecode or golden format changes.
The golden format has been slightly amended (no more comments about
`void*`, add size of the bytecode array) following the consideration
made while converting the tests.
There is also a fix: BytecodeExpectationsPrinter::top_level_ was left
uninitialized, leading to undefined behaviour.
BUG=v8:4280
LOG=N
Review URL: https://codereview.chromium.org/1717293002
Cr-Commit-Position: refs/heads/master@{#34285}
