From 910c350021d8480f2b62963a08e586963dca8182 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Sun, 9 Sep 2012 17:31:35 +0200
Subject: [PATCH] fhdl/namer: use execution order indices for variable names as
 well

---
 migen/fhdl/namer.py  | 77 ++++++++++++++++++++++++++++++++------------
 migen/fhdl/tracer.py | 28 +++++++++-------
 2 files changed, 74 insertions(+), 31 deletions(-)

diff --git a/migen/fhdl/namer.py b/migen/fhdl/namer.py
index e274e3c9..9d32a9ad 100644
--- a/migen/fhdl/namer.py
+++ b/migen/fhdl/namer.py
@@ -1,43 +1,80 @@
 from itertools import combinations
+from collections import defaultdict
 
 from migen.fhdl.structure import *
+from migen.fhdl.tracer import index_id
 
 def _bin(sig_iters):
+	# advance by one in the trace of each signal
 	status = []
 	for signal, it in sig_iters:
-		step, last = next(it)
-		status.append((signal, it, step, last))
-	terminals = []
-	bins = {}
-	for signal, it, step, last in status:
+		if it is not None:
+			step, last = next(it)
+			status.append((signal, it, step, last))
+	
+	# build bins accordingly
+	bins = defaultdict(list)
+	for signal, it, (stepname, stepidx), last in status:
 		if last:
-			terminals.append((step, signal))
-		else:
-			if step not in bins:
-				bins[step] = []
-			bins[step].append((signal, it))
-	return terminals, bins
+			it = None
+		bins[stepname].append((stepidx, signal, it))
+	return bins
 
 def _sets_disjoint(l):
 	for s1, s2 in combinations(l, 2):
 		if not s1.isdisjoint(s2):
 			return False
 	return True
-	
+
+# sig_iters contains a list of tuples (signal, iterator on the current trace position)
 def _r_build_pnd(sig_iters):
-	terminals, bins = _bin(sig_iters)
-	bins_named = [(k, _r_build_pnd(v)) for k, v in bins.items()]
+	bins = _bin(sig_iters)
+	
+	subnames = {}
+	mentions = defaultdict(list)
+	bins_named = []
+	stepindices = {}
+	
+	for stepname, next_steps in bins.items():
+		bin_content = []
+		for stepidx, signal, it in next_steps:
+			if it is None:
+				mentions[stepname].append(signal)
+			else:
+				bin_content.append((signal, it))
+			stepindices[signal] = stepidx
+		if bin_content:
+			bins_named.append((stepname, _r_build_pnd(bin_content)))
+	
 	name_sets = [set(sub_pnd.values()) for prefix, sub_pnd in bins_named]
-	r = {}
 	if not _sets_disjoint(name_sets):
 		for prefix, sub_pnd in bins_named:
-			for s, n in sub_pnd.items():
-				r[s] = prefix + "_" + n
+			for signal, subname in sub_pnd.items():
+				subname = prefix + "_" + subname
+				subnames[signal] = subname
+				mentions[subname].append(signal)
 	else:
 		for prefix, sub_pnd in bins_named:
-			r.update(sub_pnd)
-	for n, s in terminals:
-		r[s] = n
+			for signal, subname in sub_pnd.items():
+				subnames[signal] = subname
+				mentions[subname].append(signal)
+	
+	# Sort lists of mentions by step indices
+	for v in mentions.values():
+		v.sort(key=lambda x: stepindices[x])
+	
+	r = {}
+	for stepname, next_steps in bins.items():
+		for stepidx, signal, it in next_steps:
+			if it is None:
+				name = stepname
+			else:
+				name = subnames[signal]
+			if len(mentions[name]) > 1:
+				r[signal] = name + str(index_id(mentions[name], signal))
+			else:
+				r[signal] = name
+	
 	return r
 
 def last_flagged(seq):
diff --git a/migen/fhdl/tracer.py b/migen/fhdl/tracer.py
index 03051315..765dea8f 100644
--- a/migen/fhdl/tracer.py
+++ b/migen/fhdl/tracer.py
@@ -1,5 +1,6 @@
 import inspect
 from opcode import opname
+from collections import defaultdict
 
 def get_var_name(frame):
 	code = frame.f_code
@@ -25,6 +26,7 @@ def get_var_name(frame):
 		else:
 			return None
 
+name_to_idx = defaultdict(int)
 classname_to_objs = dict()
 
 def index_id(l, obj):
@@ -33,14 +35,15 @@ def index_id(l, obj):
 			return n
 	raise ValueError
 
-def trace_back(name=None):
+def trace_back(varname=None):
 	l = []
 	frame = inspect.currentframe().f_back.f_back
 	while frame is not None:
-		if name is None:
-			name = get_var_name(frame)
-		if name is not None:
-			l.insert(0, name)
+		if varname is None:
+			varname = get_var_name(frame)
+		if varname is not None:
+			l.insert(0, (varname, name_to_idx[varname]))
+			name_to_idx[varname] += 1
 		
 		try:
 			obj = frame.f_locals["self"]
@@ -50,9 +53,13 @@ def trace_back(name=None):
 			obj = None
 		
 		if obj is None:
-			modules = frame.f_globals["__name__"]
-			modules = modules.split(".")
-			objname = modules[len(modules)-1]
+			if varname is not None:
+				coname = frame.f_code.co_name
+				if coname == "<module>":
+					modules = frame.f_globals["__name__"]
+					modules = modules.split(".")
+					coname = modules[len(modules)-1]
+				l.insert(0, (coname, -1))
 		else:
 			classname = obj.__class__.__name__.lower()
 			try:
@@ -66,9 +73,8 @@ def trace_back(name=None):
 				except ValueError:
 					idx = len(objs)
 					objs.append(obj)
-			objname = classname + str(idx)
-		l.insert(0, objname)
+			l.insert(0, (classname, idx))
 		
-		name = None
+		varname = None
 		frame = frame.f_back
 	return l
-- 
2.30.2