[LLVMdev] LLVM Instruction selection matcher

محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ omerbeg at gmail.com
Sat Mar 31 10:33:24 PDT 2012


I have a few questions about matching in the selector.
1. Why does the size of the MatcherTable greatly exceed the number of
patterns defined in the target description? If it simply contains all the
variants of the patterns then what is the encoding of these entries ?
2. Is there a simple way to extract the root opcode of a pattern from the
MatcherTable entry ?
3. I believe the entries in the MatcherTable are ordered by some measure of
cost. What exactly does the cost represent and can it be retrieved while
the selector runs ?

-Omer
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120331/91ed573a/attachment.html>


More information about the llvm-dev mailing list