SSA usage question

[Richard Kenner]

I guess I should make my proposal more explicit:

(1) Add two operands to the ARRAY_REF node.  One is a copy of TYPE_MIN_VALUE
of the index and the second is a copy of TYPE_SIZE_UNIT of the element type.
(2) Add an operand to COMPONENT_REF that's a copy of DECL_FIELD_POSITION of
the second operand.

In both cases, any PLACEHOLDER_EXPRs will be expanded, the copy will be
gimplified, and the operand will not be present if it would be a constant.

Does this solve the problem?

Then I propose that we allow VIEW_CONVERT_EXPR in a nested tree of
references if it doesn't change TYPE_MODE.  It will be treated as a NOP,
just there for type-correctness purposes.