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| author | spop <spop@138bc75d-0d04-0410-961f-82ee72b054a4> | 2010-06-09 22:51:46 +0000 |
|---|---|---|
| committer | spop <spop@138bc75d-0d04-0410-961f-82ee72b054a4> | 2010-06-09 22:51:46 +0000 |
| commit | 1aabe697f03d7bb006744c168b1a51494ed2644d (patch) | |
| tree | 5c3b24046efb9af6d8d46c223e86dcc6dc93af9b /gcc/tree-ssa-loop-prefetch.c | |
| parent | dfeb6545e649ba53adf17b8d77f6499b7cb02977 (diff) | |
| download | gcc-1aabe697f03d7bb006744c168b1a51494ed2644d.tar.gz | |
Adjust the threshold value of PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO
2010-06-09 Changpeng Fang <changpeng.fang@amd.com>
* tree-ssa-loop-prefetch.c (PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO) :
Change the PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO threshold value from
8 to 4. Minor change of the related comments.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@160514 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-ssa-loop-prefetch.c')
| -rw-r--r-- | gcc/tree-ssa-loop-prefetch.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/gcc/tree-ssa-loop-prefetch.c b/gcc/tree-ssa-loop-prefetch.c index 9ccf72e18b2..705ee81b9c8 100644 --- a/gcc/tree-ssa-loop-prefetch.c +++ b/gcc/tree-ssa-loop-prefetch.c @@ -228,13 +228,13 @@ struct mem_ref_group /* Do not generate a prefetch if the unroll factor is significantly less than what is required by the prefetch. This is to avoid redundant - prefetches. For example, if prefetch_mod is 16 and unroll_factor is - 1, this means prefetching requires unrolling the loop 16 times, but - the loop is not going to be unrolled. In this case (ratio = 16), + prefetches. For example, when prefetch_mod is 16 and unroll_factor is + 2, prefetching requires unrolling the loop 16 times, but + the loop is actually unrolled twice. In this case (ratio = 8), prefetching is not likely to be beneficial. */ #ifndef PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO -#define PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO 8 +#define PREFETCH_MOD_TO_UNROLL_FACTOR_RATIO 4 #endif /* The memory reference. */ |