diff options
| author | Chris Lattner <sabre@nondot.org> | 2004-07-23 05:26:05 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2004-07-23 05:26:05 +0000 |
| commit | fe1630b43ef3e9506fde9780108c2af0431393e9 (patch) | |
| tree | 33b81a877689b7d5eebf5712270e0de185739eb2 /lib/CodeGen/PHIElimination.cpp | |
| parent | eed80e23751ecc50c1fa5604f67be4b826d5b417 (diff) | |
Force coallescing of live ranges that have a single definition, even if they
interfere. Because these intervals have a single definition, and one of them
is a copy instruction, they are always safe to merge even if their lifetimes
interfere. This slightly reduces the amount of spill code, for example on
252.eon, from:
12837 spiller - Number of loads added
7604 spiller - Number of stores added
5842 spiller - Number of register spills
18155 liveintervals - Number of identity moves eliminated after coalescing
to:
12754 spiller - Number of loads added
7585 spiller - Number of stores added
5803 spiller - Number of register spills
18262 liveintervals - Number of identity moves eliminated after coalescing
The much much bigger win would be to merge intervals with multiple definitions
(aka phi nodes) but this is not that day.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15124 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/PHIElimination.cpp')
0 files changed, 0 insertions, 0 deletions