On 4/18/22 16:41, Paul Koning via Gcc wrote:
In switch statements with dense case values, the typical result is a jump
table, which is fast. If the values are sparse, a tree of compares is
generated instead.
What if nearly all cases are dense but there are a few outliers? An example appears
In switch statements with dense case values, the typical result is a jump
table, which is fast. If the values are sparse, a tree of compares is
generated instead.
What if nearly all cases are dense but there are a few outliers? An example
appears in the NFS protocol parser, where you get a sw
Joern RENNECKE schrieb:
In http://gcc.gnu.org/ml/gcc/2006-07/msg00156.html, your wrote:
We could use a cheap hash and base start compare / branch trees in
every hash bin.
Say we have a 16 k range, 200 nodes, and want to keep the hash
bin/node ratio between 2 and 4.
Let i be the switch argume
In http://gcc.gnu.org/ml/gcc/2006-07/msg00156.html, your wrote:
A paper at this year's GCC Summit talked about this:
http://www.gccsummit.org/2006/view_abstract.php?content_key=18
You might like to follow up with Edmar (the author of the paper).
But that was about optimizing the trees for an
A paper at this year's GCC Summit talked about this:
http://www.gccsummit.org/2006/view_abstract.php?content_key=18
You might like to follow up with Edmar (the author of the paper).
Cheers, Ben
Hi,
while dealing with autogenerated code I found that GCC often outputs compare
trees instead of branch tables for switch statements. I found that GCC uses the
density of case labels within their spanned range as the key criterion. If the
density of labels is smaller than 10% (33% for size op
