From 46264f4642ce25f02a39c2e012c90d783e812e9e Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Sun, 18 Sep 2022 16:23:20 +0100 Subject: [PATCH] comment principle behind new tables in power_insn.py https://libre-soc.org/irclog/%23libre-soc.2022-09-18.log.html#t2022-09-18T16:22:37 --- src/openpower/decoder/power_insn.py | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/openpower/decoder/power_insn.py b/src/openpower/decoder/power_insn.py index 059d39b3..96077e14 100644 --- a/src/openpower/decoder/power_insn.py +++ b/src/openpower/decoder/power_insn.py @@ -1751,6 +1751,12 @@ class RM(BaseRM): def select(self, record, Rc): rm = self + # the idea behind these tables is that they are now literally + # in identical format to insndb.csv and minor_xx.csv and can + # be done precisely as that. the only thing to watch out for + # is the insertion of Rc=1 as a "mask/value" bit and likewise + # regtype detection (3-bit BF/BFA, 5-bit BA/BB/BT) also inserted + # as the LSB. table = None if record.svp64.mode is _SVMode.NORMAL: # concatenate mode 5-bit with Rc (LSB) then do a mask/map search -- 2.30.2