[pypy-svn] r7527 - pypy/trunk/src/pypy/translator

[mgedmin at codespeak.net]

Author: mgedmin
Date: Sat Nov 20 19:02:20 2004
New Revision: 7527

Modified:
   pypy/trunk/src/pypy/translator/transform.py
Log:
Ignore blocked blocks during transformations.  This fixes a bunch of assertion
errors if you are transforming a flow graph that contains blocked blocks.

This doesn't change anything in practice because if there are any blocked
blocks, the annotator raises an assertion error and no transformations are
performed.  Armin suggested that in some instances (e.g. calling a function
that always raises an exception) the blocked block should stay blocked and we
should proceed with the translation anyway.



Modified: pypy/trunk/src/pypy/translator/transform.py
==============================================================================
--- pypy/trunk/src/pypy/translator/transform.py	(original)
+++ pypy/trunk/src/pypy/translator/transform.py	Sat Nov 20 19:02:20 2004
@@ -19,9 +19,15 @@
 # -->
 # d = alloc_and_set(b, a)
 
+def fully_annotated_blocks(self):
+    """Ignore blocked blocks."""
+    for block, is_annotated in self.annotated.iteritems():
+        if is_annotated:
+            yield block
+
 def transform_allocate(self):
     """Transforms [a] * b to alloc_and_set(b, a) where b is int."""
-    for block in self.annotated:
+    for block in fully_annotated_blocks(self):
         operations = block.operations[:]
         n_op = len(operations)
         for i in range(0, n_op-1):
@@ -46,7 +52,7 @@
 
 def transform_slice(self):
     """Transforms a[b:c] to getslice(a, b, c)."""
-    for block in self.annotated:
+    for block in fully_annotated_blocks(self):
         operations = block.operations[:]
         n_op = len(operations)
         for i in range(0, n_op-1):
@@ -112,7 +118,7 @@
     variable_flow = {}  # map {Var: list-of-Vars-it-depends-on}
     
     # compute variable_flow and an initial read_vars
-    for block in self.annotated:
+    for block in fully_annotated_blocks(self):
         # figure out which variables are ever read
         for op in block.operations:
             if op.opname not in CanRemove:  # mark the inputs as really needed
@@ -151,7 +157,7 @@
                 read_vars[prevvar] = True
                 pending.append(prevvar)
 
-    for block in self.annotated:
+    for block in fully_annotated_blocks(self):
         
         # look for removable operations whose result is never used
         for i in range(len(block.operations)-1, -1, -1):
@@ -175,12 +181,16 @@
         # link.target.inputargs.
         for link in block.exits:
             assert len(link.args) == len(link.target.inputargs)
+            if not self.annotated.get(link.target, False):
+                # Can't remove -- link.target is not annotated, therefore
+                # link.target.inputargs will never be touched
+                continue
             for i in range(len(link.args)-1, -1, -1):
                 if link.target.inputargs[i] not in read_vars:
                     del link.args[i]
             # the above assert would fail here
 
-    for block in self.annotated:
+    for block in fully_annotated_blocks(self):
         # look for input variables never used
         # The corresponding link.args have already been all removed above
         for i in range(len(block.inputargs)-1, -1, -1):
@@ -314,11 +324,7 @@
     """Remove dead code: these are the blocks that are not annotated at all
     because the annotation considered that no conditional jump could reach
     them."""
-    for block, is_annotated in self.annotated.items():
-        if not is_annotated:
-            # We do not want to accidentally turn blocked blocks into return
-            # blocks
-            continue
+    for block in fully_annotated_blocks(self):
         for link in block.exits:
             if link not in self.links_followed:
                 lst = list(block.exits)