V4 interpreter: remove stack-slot allocator.

The life-ranges are only valid when the IR is in SSA form. So the use
of them in the interpreter after converting out of SSA form introduced
bugs. Instead, allocate a stack-slot for each unique temporary, and
re-use the code for this from the JIT.

Change-Id: I294f1116064f0b85996cf96a0b408b41a3c785e2
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
V4: fix loop block marking for initializer blocks.

Any new blocks generated as part of the initializer were incorrectly
marked as belonging to a loop. For example, if a LocalForStatement
would contain a ternary expression, the generated then and else blocks
would be marked. This would confuse the block scheduling, because all
blocks are postponed unil the condition block (“group start”) is
scheduled.

Task-number: QTBUG-33754

Change-Id: I45919ebeac356f015bb91fe0210472b3df0b56d8
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
V4 IR: scan arguments when entering function scope in QML.

When doing IR generation for a function declaration in a QML object,
call through the helper methods to check for forbidden names, and most
importantly, also checks if the function has parameters. If the latter
is the case, they need to be added as a member for the current scope
in order to get IR generation correct.

Task-number: QTBUG-34493

Change-Id: I0ade15ee19e1b1ac8ee2f2d3fa186d1551800199
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
V4 JIT: fix invalid sanity assert.

If there are multiple incoming edges to a block, and there are one or
more phi nodes at the start, then only check the temp uses for the edge
we are resolving.

Task-number: QTBUG-34770

Change-Id: Ibb5c7c323d6be8bc1ed492b08ed098de2f2726cc
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>