tree aed74cab5b4eccb428760eaf674e3fcb53873af9
parent 0300a464a4ccdfac0052fcc0524a67592e9b19e8
author alan-baker <33432579+alan-baker@users.noreply.github.com> 1554213928 -0400
committer GitHub <noreply@github.com> 1554213928 -0400
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Fix merge return in the face of breaks (#2466)

Fixes #2453

* Enable addition of OpPhi instructions when the loop has multiple
predecessors of the merge due to a break
 * This can result in some values no longer dominating their uses
* Track return blocks in structured flow to produce OpPhis that have
multiple undef and non-undef arguments
* New tests to catch the bug
* When a block is predicated, mark the new body as a return if the old
block as already a return