Commit Graph

3 Commits

Author SHA1 Message Date
Nuno Lopes fa0dffccee teach instcombine to remove allocated buffers even if there are stores, memcpy/memmove/memset, and objectsize users.
This means we can do cheap DSE for heap memory.
Nothing is done if the pointer excapes or has a load.

The churn in the tests is mostly due to objectsize, since we want to make sure we
don't delete the malloc call before evaluating the objectsize (otherwise it becomes -1/0)

llvm-svn: 159876
2012-07-06 23:09:25 +00:00
Duncan Sands f162eace49 Teach instCombine to remove malloc+free if malloc's only uses are comparisons
to null.  Patch by Matti Niemenmaa.

llvm-svn: 104871
2010-05-27 19:09:06 +00:00
Chris Lattner 463716d559 instcombine shouldn't delete all null checks for mallocs.
This fixes PR5130.

llvm-svn: 83290
2009-10-05 02:47:47 +00:00