types2 will give us a constant with a type T, if an untyped constant is
used with another operand of type T (in a provably correct way). When we
substitute in the type args during stenciling, we now know the real type
of the constant. We may then need to change the BasicLit.val to be the
correct type (e.g. convert an int64Val constant to a floatVal constant).
Otherwise, later parts of the compiler will be confused.
Updated tests list.go and double.go with uses of untyped constants.
Change-Id: I9966bbb0dea3a7de1c5a6420f8ad8af9ca84a33e
Reviewed-on: https://go-review.googlesource.com/c/go/+/303089
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
For Builtin ops, we currently stay with using the old
typechecker to transform the call to a more specific expression
and possibly use more specific ops. However, for a bunch of the
ops, we delay calling the old typechecker if any of the args have
type params, for a variety of reasons.
In the near future, we will start creating separate functions that do
the same transformations as the old typechecker for calls, builtins,
indexing, comparisons, etc. These functions can then be called at noder
time for nodes with no type params, and at stenciling time for nodes
with type params.
Remove unnecessary calls to types1 typechecker for most kinds of
statements (still need it for SendStmt, AssignStmt, ReturnStmt, and
SelectStmt). In particular, we don't need it for RangeStmt, and this
avoids some complaints by the types1 typechecker on generic code.
Other small changes:
- Fix check on whether to delay calling types1-typechecker on type
conversions. Should check if HasTParam is true, rather than if the
type is directly a TYPEPARAM.
- Don't call types1-typechecker on an indexing operation if the left
operand has a typeparam in its type and is not obviously a TMAP,
TSLICE, or TARRAY. As above, we will eventually have to create a new
function that can do the required transformations (for complicated
cases) at noder time or stenciling time.
- Copy n.BuiltinOp in subster.node()
- The complex arithmetic example in absdiff.go now works.
- Added new tests double.go and append.go
- Added new example with a new() call in settable.go
Change-Id: I8f377afb6126cab1826bd3c2732aa8cdf1f7e0b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/301951
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
