Dup splat array in certain cases where there is a block argument #3157
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This makes:
call
foo
with 1, 2, and the lambda, in addition to passing thelambda as a block. This is different from the previous behavior,
which passed the lambda as a block but not as a regular argument,
which goes against the expected left-to-right evaluation order.
This is how Ruby already compiled arguments if using leading
arguments, trailing arguments, or keywords in the same call.
This works by disabling the optimization that skipped duplicating
the array during the splat (splatarray instruction argument
switches from false to true). In the above example, the splat
call duplicates the array. I've tested and cases where a
local variable or symbol are used do not duplicate the array,
so I don't expect this to decrease the performance of most Ruby
programs. However, programs such as:
could see a decrease in performance, if
bar
is a method calland not a local variable.
This is not a perfect solution, there are ways to get around
this:
A perfect solution would require completely disabling the
optimization.
Fixes [Bug #16504]
Fixes [Bug #16500]