| commit | 8c08c764f0a0e5de5be15fa7b5a1fa49392e7546 | |
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | |
| Wed, 8 Dec 2004 03:05:09 +0000 (7 20:05 -0700) | ||
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | |
| Fri, 8 Apr 2005 04:05:35 +0000 (7 21:05 -0700) | ||
| tree | f6a166e4fd726b7ab37609fbd15b376c22ddddf1 | treesnapshot (tar.gz zip) |
| parent | 2d8d9bda591831a9d0acc478f7d3b8fa35032b6e | commitdiff |
Be more aggressive on PHI-node CSE.
We don't care _where_ a PHI-node is, since the real location
is at the phi sources. So unlike other instructions, we do not
bother with any dominance analysis - we can just combine them
blindly across basic block borders.
It might make sense to totally disconnect the PHI nodes from
the flow graph to make this lack of positional information
even more explicit. That might also allow us to combine more
basic blocks.
We don't care _where_ a PHI-node is, since the real location
is at the phi sources. So unlike other instructions, we do not
bother with any dominance analysis - we can just combine them
blindly across basic block borders.
It might make sense to totally disconnect the PHI nodes from
the flow graph to make this lack of positional information
even more explicit. That might also allow us to combine more
basic blocks.
| cse.c | diffblobblamehistory |