Commit Graph

2 Commits

Author SHA1 Message Date
Dan Gohman 40503396da Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81290
2009-09-08 23:54:48 +00:00
Evan Cheng a9cda8abf2 Added optimization that narrow load / op / store and the 'op' is a bit twiddling instruction and its second operand is an immediate. If bits that are touched by 'op' can be done with a narrower instruction, reduce the width of the load and store as well. This happens a lot with bitfield manipulation code.
e.g.
orl     $65536, 8(%rax)
=>
orb     $1, 10(%rax)

Since narrowing is not always a win, e.g. i32 -> i16 is a loss on x86, dag combiner consults with the target before performing the optimization.

llvm-svn: 72507
2009-05-28 00:35:15 +00:00