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docs(tvix/eval): builtins.add is not equivalent to +

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While it is in the given example, i.e. for integer addition, to claim
that they are equivalent is a bit misleading: builtins.add is less
overloaded than +, i.e. builtins.add "foo" "bar" will fail whereas
"foo" + "bar" performs string concatenation.

Change-Id: Ib52d530d1ab289b367565b286f06a76dd518d4fb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7929
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
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sterni 2023-01-25 14:39:24 +01:00 committed by clbot
parent 669496f0ba
commit 8a8325fb9d
1 changed files with 3 additions and 3 deletions
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6
tvix/eval/docs/known-optimisation-potential.md
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@ -64,8 +64,8 @@ optimisations, but note the most important ones here.
* Inline fully applied builtins with equivalent operators [medium]
Some `builtins` have equivalent operators, e.g. `builtins.add`
corresponds to the `+` operator, `builtins.hasAttr` to the `?`
Some `builtins` have equivalent operators, e.g. `builtins.sub`
corresponds to the `-` operator, `builtins.hasAttr` to the `?`
operator etc. These operators additionally compile to a primitive
VM opcode, so they should be just as cheap (if not cheaper) as
a builtin application.
@ -73,7 +73,7 @@ optimisations, but note the most important ones here.
In case the compiler encounters a fully applied builtin (i.e.
no currying is occurring) and the `builtins` global is unshadowed,
it could compile the equivalent operator bytecode instead: For
example, `builtins.add 20 22` would be compiled as `20 + 22`.
example, `builtins.sub 20 22` would be compiled as `20 - 22`.
This would ensure that equivalent `builtins` can also benefit
from special optimisations we may implement for certain operators
(in the absence of currying). E.g. we could optimise access