new loplugin inlineablemethods

look for methods that are:

(*) non-virtual
(*) only called once
(*) only called from inside their own class
(*) small i.e. < 40 characters

which are candidates for just having their code inlined

Change-Id: I0e9e8125d140282cdcdd2a77374059b17b2fcd7d

compilerplugins/clang/inlineablemethods.py

+#!/usr/bin/python
+
+import sys
+import re
+import io
+
+# --------------------------------------------------------------------------------------------
+# globals
+# --------------------------------------------------------------------------------------------
+
+definitionSet = set() # set of tuple(return_type, name_and_params)
+definitionToSourceLocationMap = dict()
+calledFromDict = dict()
+calledFromOutsideSet = set()
+largeFunctionSet = set() # set of tuple(return_type, name_and_params)
+addressOfSet = set() # set of tuple(return_type, name_and_params)
+
+# clang does not always use exactly the same numbers in the type-parameter vars it generates
+# so I need to substitute them to ensure we can match correctly.
+normalizeTypeParamsRegex = re.compile(r"type-parameter-\d+-\d+")
+def normalizeTypeParams( line ):
+    return normalizeTypeParamsRegex.sub("type-parameter-?-?", line)
+
+# --------------------------------------------------------------------------------------------
+# primary input loop
+# --------------------------------------------------------------------------------------------
+
+# The parsing here is designed to avoid grabbing stuff which is mixed in from gbuild.
+# I have not yet found a way of suppressing the gbuild output.
+with io.open("loplugin.inlineablemethods.log", "rb", buffering=1024*1024) as txt:
+    for line in txt:
+        tokens = line.strip().split("\t")
+        if tokens[0] == "definition:":
+            access = tokens[1]
+            returnType = tokens[2]
+            nameAndParams = tokens[3]
+            sourceLocation = tokens[4]
+            funcInfo = (normalizeTypeParams(returnType), normalizeTypeParams(nameAndParams))
+            definitionSet.add(funcInfo)
+            definitionToSourceLocationMap[funcInfo] = sourceLocation
+        elif tokens[0] == "calledFrom:":
+            calleeLocation = tokens[1]
+            returnType = tokens[2]
+            nameAndParams = tokens[3]
+            funcInfo = (normalizeTypeParams(returnType), normalizeTypeParams(nameAndParams))
+            if not funcInfo in calledFromDict:
+                calledFromDict[funcInfo] = set()
+            calledFromDict[funcInfo].add(calleeLocation)
+        elif tokens[0] == "outside:":
+            returnType = tokens[1]
+            nameAndParams = tokens[2]
+            calledFromOutsideSet.add((normalizeTypeParams(returnType), normalizeTypeParams(nameAndParams)))
+        elif tokens[0] == "large:":
+            returnType = tokens[1]
+            nameAndParams = tokens[2]
+            largeFunctionSet.add((normalizeTypeParams(returnType), normalizeTypeParams(nameAndParams)))
+        elif tokens[0] == "addrof:":
+            returnType = tokens[1]
+            nameAndParams = tokens[2]
+            addressOfSet.add((normalizeTypeParams(returnType), normalizeTypeParams(nameAndParams)))
+        else:
+            print( "unknown line: " + line)
+
+# Invert the definitionToSourceLocationMap.
+# If we see more than one method at the same sourceLocation, it's being autogenerated as part of a template
+# and we should just ignore it.
+sourceLocationToDefinitionMap = {}
+for k, v in definitionToSourceLocationMap.iteritems():
+    sourceLocationToDefinitionMap[v] = sourceLocationToDefinitionMap.get(v, [])
+    sourceLocationToDefinitionMap[v].append(k)
+for k, definitions in sourceLocationToDefinitionMap.iteritems():
+    if len(definitions) > 1:
+        for d in definitions:
+            definitionSet.remove(d)
+
+def isOtherConstness( d, callSet ):
+    method = d[0] + " " + d[1]
+    # if this method is const, and there is a non-const variant of it, and the non-const variant is in use, then leave it alone
+    if d[0].startswith("const ") and d[1].endswith(" const"):
+        if ((d[0][6:],d[1][:-6]) in callSet):
+           return True
+    elif method.endswith(" const"):
+        method2 = method[:len(method)-6] # strip off " const"
+        if ((d[0],method2) in callSet):
+           return True
+    if method.endswith(" const") and ("::iterator" in method):
+        method2 = method[:len(method)-6] # strip off " const"
+        method2 = method2.replace("::const_iterator", "::iterator")
+        if ((d[0],method2) in callSet):
+           return True
+    # if this method is non-const, and there is a const variant of it, and the const variant is in use, then leave it alone
+    if (not method.endswith(" const")) and ((d[0],"const " + method + " const") in callSet):
+           return True
+    if (not method.endswith(" const")) and ("::iterator" in method):
+        method2 = method.replace("::iterator", "::const_iterator") + " const"
+        if ((d[0],method2) in callSet):
+           return True
+    return False
+
+# sort the results using a "natural order" so sequences like [item1,item2,item10] sort nicely
+def natural_sort_key(s, _nsre=re.compile('([0-9]+)')):
+    return [int(text) if text.isdigit() else text.lower()
+            for text in re.split(_nsre, s)]
+def sort_set_by_natural_key(s):
+    return sorted(s, key=lambda v: natural_sort_key(v[1]))
+
+    
+# --------------------------------------------------------------------------------------------
+# Methods that are only called from inside their own class, and are only called from one spot
+# --------------------------------------------------------------------------------------------
+
+tmp4set = set()
+for d in definitionSet:
+    if d in calledFromOutsideSet:
+        continue
+    if isOtherConstness(d, calledFromOutsideSet):
+        continue
+    if d not in definitionToSourceLocationMap:
+        print("warning, method has no location: " + d[0] + " " + d[1])
+        continue
+    # ignore external code
+    if definitionToSourceLocationMap[d].startswith("external/"):
+       continue
+    # ignore constructors, calledFromOutsideSet does not provide accurate info for them
+    tokens = d[1].split("(")[0].split("::")
+    if len(tokens)>1 and tokens[-2] == tokens[-1]:
+        continue
+    # ignore large methods, which make the code clearer by being out of line
+    if d in largeFunctionSet:
+        continue
+    # ignore methods whose address we take
+    if d in addressOfSet:
+        continue
+    # ignore unused methods, leave them to the dedicated analysis
+    if d not in calledFromDict:
+        continue
+    # ignore methods called from more than one site
+    if len(calledFromDict[d]) > 1:
+        continue
+
+    method = d[0] + " " + d[1]
+    tmp4set.add((method, definitionToSourceLocationMap[d]))
+
+# print output, sorted by name and line number
+with open("loplugin.inlineablemethods.report", "wt") as f:
+    for t in sort_set_by_natural_key(tmp4set):
+        f.write(t[1] + "\n")
+        f.write("    " + t[0] + "\n")