[pypy-svn] pypy default: Optimize frame creation by the JIT by making the default value

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r43213:a7a6d25abf34
Date: 2011-04-08 12:22 +0200
http://bitbucket.org/pypy/pypy/changeset/a7a6d25abf34/

Log:	Optimize frame creation by the JIT by making the default value of
	these two fields be 0 instead of -1.

diff --git a/pypy/interpreter/executioncontext.py b/pypy/interpreter/executioncontext.py
--- a/pypy/interpreter/executioncontext.py
+++ b/pypy/interpreter/executioncontext.py
@@ -519,7 +519,7 @@
             return
         code = frame.pycode
         if frame.instr_lb <= frame.last_instr < frame.instr_ub:
-            if frame.last_instr <= frame.instr_prev:
+            if frame.last_instr < frame.instr_prev_plus_one:
                 # We jumped backwards in the same line.
                 executioncontext._trace(frame, 'line', self.space.w_None)
         else:
@@ -557,5 +557,5 @@
                 frame.f_lineno = line
                 executioncontext._trace(frame, 'line', self.space.w_None)
 
-        frame.instr_prev = frame.last_instr
+        frame.instr_prev_plus_one = frame.last_instr + 1
         self.space.frame_trace_action.fire()     # continue tracing

diff --git a/pypy/interpreter/pyframe.py b/pypy/interpreter/pyframe.py
--- a/pypy/interpreter/pyframe.py
+++ b/pypy/interpreter/pyframe.py
@@ -46,8 +46,8 @@
     w_f_trace                = None
     # For tracing
     instr_lb                 = 0
-    instr_ub                 = -1
-    instr_prev               = -1
+    instr_ub                 = 0
+    instr_prev_plus_one      = 0
     is_being_profiled        = False
 
     def __init__(self, space, code, w_globals, closure):
@@ -335,7 +335,7 @@
 
             w(self.instr_lb), #do we need these three (that are for tracing)
             w(self.instr_ub),
-            w(self.instr_prev),
+            w(self.instr_prev_plus_one),
             w_cells,
             ]
 
@@ -349,7 +349,7 @@
         args_w = space.unpackiterable(w_args)
         w_f_back, w_builtin, w_pycode, w_valuestack, w_blockstack, w_exc_value, w_tb,\
             w_globals, w_last_instr, w_finished, w_f_lineno, w_fastlocals, w_f_locals, \
-            w_f_trace, w_instr_lb, w_instr_ub, w_instr_prev, w_cells = args_w
+            w_f_trace, w_instr_lb, w_instr_ub, w_instr_prev_plus_one, w_cells = args_w
 
         new_frame = self
         pycode = space.interp_w(PyCode, w_pycode)
@@ -397,7 +397,7 @@
 
         new_frame.instr_lb = space.int_w(w_instr_lb)   #the three for tracing
         new_frame.instr_ub = space.int_w(w_instr_ub)
-        new_frame.instr_prev = space.int_w(w_instr_prev)
+        new_frame.instr_prev_plus_one = space.int_w(w_instr_prev_plus_one)
 
         self._setcellvars(cellvars)
         # XXX what if the frame is in another thread??