Adds min-preludes to a few more slowest tests, and adds them to most of
the lowering tests, with a few exceptions that make use of operators.
This take the runtime of file_test down from about 8s to about 7s on my
machine.
We add support for Negate on uints in the min-preludes.
Remove use of i32/bool when a builtin type or test-define class type can
work. Make `Sub` user-defines in a test that is testing builtin
functions and not trying to test the prelude, in the same way that it
defines its own Negate. Reduce use of the + operator when it isn't
contributing to the test's coverage, since the + operator needs the full
prelude. Remove use of Core.Print when it's not required for the test.
Move `deduce_nested_facet_value.carbon` to its own file since it uses
TypeAnd, and the rest of deduce.carbon does not, but uses i32. This
means they can each use a different min-prelude.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
The same specific function will (eventually) be emitted as part of
lowering multiple different source files, so don't give them unique
external linkage.
This allows us to import the table for a given impl only once, while we
can import many ImplWitness instructions with different specifics for a
generic impl.
For example in convert_facet_value_to_narrowed_facet_type.carbon we see
that a single witness table is imported for the BitAnd interface, with
multiple witnesses (for different specifics) imported and sharing the
same table.
The ImplWitnessTable now contains a back-link to the Impl the witness is
for, allowing inst namer to name that interface in the textual semir,
and allowing the interface to be found when debugging from a witness.
---------
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
When performing a call through an impl witness, the callee that we
type-check against is the function in the interface, so we form a
specific for that callee. However, once the impl witness access
resolves, the eventual callee is a different function -- the function in
the impl -- so this would cause us to form a `SpecificFunction` where
the callee is one function but the specific refers to a different
function.
Address this by adding another instruction, `SpecificImplFunction`, that
takes a function in an impl and a specific for the corresponding
function in the interface, and computes and returns a `SpecificFunction`
referring to the corresponding specific function in the impl, or returns
a direct reference to the function in the `impl` if it's not a generic
function.