I extended the Int64Lowering to lower calls, loads, stores, returns, and
parameters and apply the lowering on both the test function TF graph and
the WasmRunner TF graph.
The lowering of calls also requires an adjustment of the call descriptor.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1704033002
Cr-Commit-Position: refs/heads/master@{#34121}
The goal of the Int64Reducer is to replace all int64 nodes in a tf graph
with a set of int32 nodes such that 64 bit tf functions can be executed
on 32 bit platforms. At the moment the Int64Reducer only replaces
Int64Constants, TruncateInt64ToInt32, and Word64And.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1655883002
Cr-Commit-Position: refs/heads/master@{#33721}
