cmd/compile: create/use noder2 transform functions for more node types
Pull out the transformation part of the typechecking functions for:
- assignment statements
- return statements
- send statements
- select statements
- type conversions
- normal function/method calls
- index operations
The transform functions are like the original typechecking functions,
but with all code removed related to:
- Detecting compile-time errors (already done by types2)
- Setting the actual type of existing nodes (already done based on
info from types2)
- Dealing with untyped constants
Moved all the transformation functions to a separate file, transform.go.
Continuing with the same pattern, we delay transforming a node if it has
any type params in its args, marking it with a typecheck flag of 3, and
do the actual transformation during stenciling.
Assignment statements are tricky, since their transformation must be
delayed if any of the left or right-hands-sides are delayed.
Still to do are:
- selector expressions (OXDOT)
- composite literal expressions (OCOMPLIT)
- builtin function calls
Change-Id: Ie608cadbbc69b40db0067a5536cf707dd974aacc
Reviewed-on: https://go-review.googlesource.com/c/go/+/304049
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>