incorrect gvn memcpy simplification #2449
Description
| Bugzilla Link | 2077 |
| Resolution | FIXED |
| Resolved on | Feb 24, 2008 22:08 |
| Version | unspecified |
| OS | Linux |
| Attachments | testcase .ll |
| Reporter | LLVM Bugzilla Contributor |
Extended Description
The function @badly_optimized does:
initialize %memtmp (by calling @initialize)
memcpy %memtmp to %tmp
memcpy %tmp to %z
pass %z to @passed_uninitialized
After GVN (opt -gvn) it does:
initialize %tmp (by calling @initialize)
memcpy %memtmp to %z <= This is not "memcpy %tmp to %z"!
pass %z to @passed_uninitialized