From f0f302d80683c9b68fc9b13dac9f590ae1937232 Mon Sep 17 00:00:00 2001
From: Alain D D Williams <addw@phcomp.co.uk>
Date: Tue, 13 Oct 2020 17:54:10 +0100
Subject: [PATCH] attempt at counting output registers

---
 openpower/sv_analysis.py | 40 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 36 insertions(+), 4 deletions(-)

diff --git a/openpower/sv_analysis.py b/openpower/sv_analysis.py
index ee029a5c5..8f4d266e4 100644
--- a/openpower/sv_analysis.py
+++ b/openpower/sv_analysis.py
@@ -1,23 +1,33 @@
 #!/usr/bin/env python3
+# Initial version written by lkcl Oct 2020
+# This program analyses the Power 9 op codes and looks at in/out register uses
+# The results are displayed:
+#	https://libre-soc.org/openpower/opcode_regs_deduped/
+#
+# It finds .csv files in the directory isatables/
+
 import csv
 import os
 from os.path import dirname, join
 from glob import glob
 from collections import OrderedDict
 
-
+# Return absolute path (ie $PWD) + isatables + name
 def find_wiki_file(name):
     filedir = os.path.dirname(os.path.abspath(__file__))
     tabledir = join(filedir, 'isatables')
     file_path = join(tabledir, name) 
     return file_path
 
+# Return an array of dictionaries from the CSV file name:
 def get_csv(name):
     file_path = find_wiki_file(name)
     with open(file_path, 'r') as csvfile:
         reader = csv.DictReader(csvfile)
         return list(reader)
 
+# This will return True if all values are true.
+# Not sure what this is about
 def blank_key(row):
     #for v in row.values():
     #    if 'SPR' in v: # skip all SPRs
@@ -27,14 +37,19 @@ def blank_key(row):
             return False
     return True
 
+# General purpose registers have names like: RA, RT, R1, ...
+# Floating point registers names like: FRT, FRA, FR1, ..., FRTp, ...
+# Return True if field is a register
 def isreg(field):
     return field.startswith('R') or field.startswith('FR')
 
 
+# These are the attributes of the instructions,
+# register names
 keycolumns = ['unit', 'in1', 'in2', 'in3', 'out', 'CR in', 'CR out',
                  ] # don't think we need these: 'ldst len', 'rc', 'lk']
 
-tablecols = ['unit', 'in', 'out', 'CR in', 'CR out',
+tablecols = ['unit', 'in', 'out', 'CR in', 'CR out', 'outcnt',
                  ] # don't think we need these: 'ldst len', 'rc', 'lk']
 
 def create_key(row):
@@ -47,13 +62,21 @@ def create_key(row):
                 res['in'] = 0
             if isreg(row[key]):
                 res['in'] += 1
+
         # registers OUT
         if key == 'out':
             if isreg(row[key]):
                 res[key] = 'R'
             else:
                 res[key] = '0'
-        # CRs
+
+            # If upd is 1 then increment the count of outputs
+            if 'outcnt' not in res:
+                res['outcnt'] = 0
+            if row['upd'] == '1':
+                res['outcnt'] += 1
+
+        # CRs (Condition Register) (CR0 .. CR7)
         if key.startswith('CR'):
             if row[key].startswith('NONE'):
                 res[key] = '0'
@@ -65,7 +88,7 @@ def create_key(row):
                 res[key] = row[key]
             else:
                 res[key] = 'OTHER'
-        # LDST len
+        # LDST len (LoadStore length)
         if key.startswith('ldst'):
             if row[key].startswith('NONE'):
                 res[key] = '0'
@@ -82,10 +105,13 @@ def create_key(row):
         if key == 'lk':
             res[key] = row[key]
 
+    # Convert the numerics 'in' & 'outcnt' to strings
     res['in'] = str(res['in'])
+    res['outcnt'] = str(res['outcnt'])
 
     return res
 
+#
 def dformat(d):
     res = []
     for k, v in d.items():
@@ -118,7 +144,10 @@ def process_csvs():
     primarykeys = set()
     dictkeys = OrderedDict()
 
+    # Expand that (all .csv files)
     pth = find_wiki_file("*.csv")
+
+    # Ignore those containing: valid test sprs
     for fname in glob(pth):
         if 'valid' in fname:
             continue
@@ -126,8 +155,10 @@ def process_csvs():
             continue
         if 'sprs' in fname:
             continue
+
         #print (fname)
         csvname = os.path.split(fname)[1]
+        # csvname is something like: minor_59.csv, fname the whole path
         csv = get_csv(fname)
         csvs[fname] = csv
         for row in csv:
@@ -135,6 +166,7 @@ def process_csvs():
                 continue
             dkey = create_key(row)
             key = tuple(dkey.values())
+            # print("key=", key)
             dictkeys[key] = dkey
             primarykeys.add(key)
             if key not in bykey:
-- 
2.30.2