[pypy-commit] pypy shadowstack-perf: Disable usage of the register for non-standalone translations.

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: shadowstack-perf
Changeset: r45429:622cdee7ad2d
Date: 2011-07-08 21:48 +0200
http://bitbucket.org/pypy/pypy/changeset/622cdee7ad2d/

Log:	Disable usage of the register for non-standalone translations.

diff --git a/pypy/translator/c/database.py b/pypy/translator/c/database.py
--- a/pypy/translator/c/database.py
+++ b/pypy/translator/c/database.py
@@ -60,7 +60,8 @@
         if translator is None or translator.rtyper is None:
             self.exctransformer = None
         else:
-            self.exctransformer = translator.getexceptiontransformer()
+            self.exctransformer = translator.getexceptiontransformer(
+                standalone=standalone)
         if translator is not None:
             self.gctransformer = self.gcpolicy.transformerclass(translator)
         self.completed = False
diff --git a/pypy/translator/exceptiontransform.py b/pypy/translator/exceptiontransform.py
--- a/pypy/translator/exceptiontransform.py
+++ b/pypy/translator/exceptiontransform.py
@@ -52,8 +52,9 @@
 
 class BaseExceptionTransformer(object):
 
-    def __init__(self, translator):
+    def __init__(self, translator, standalone):
         self.translator = translator
+        self.standalone = standalone
         self.raise_analyzer = canraise.RaiseAnalyzer(translator)
         edata = translator.rtyper.getexceptiondata()
         self.lltype_of_exception_value = edata.lltype_of_exception_value
@@ -73,19 +74,21 @@
             assertion_error_ll_exc_type)
         self.c_n_i_error_ll_exc_type = constant_value(n_i_error_ll_exc_type)
 
-        if register.register_number is not None:
+        use_special_reg = standalone and register.register_number is not None
+        self.use_special_reg = use_special_reg
+        if use_special_reg:
             self.c_nonnull_specialregister = constant_value(register.nonnull)
             self.c_load_from_reg = constant_value(register.load_from_reg)
             self.c_reg_is_nonnull = constant_value(register.reg_is_nonnull)
             self.c_store_into_reg = constant_value(register.store_into_reg)
 
         def rpyexc_occured():
-            if register.register_number is None:
+            if use_special_reg:
+                # an exception occurred iff the special register is 0
+                return register.load_from_reg() == llmemory.NULL
+            else:
                 exc_type = exc_data.exc_type
                 return bool(exc_type)
-            else:
-                # an exception occurred iff the special register is 0
-                return register.load_from_reg() == llmemory.NULL
 
         def rpyexc_fetch_type():
             return exc_data.exc_type
@@ -94,7 +97,7 @@
             return exc_data.exc_value
 
         def rpyexc_clear():
-            if register.register_number is not None:
+            if use_special_reg:
                 register.store_into_reg(register.nonnull)
             exc_data.exc_type = null_type
             exc_data.exc_value = null_value
@@ -112,14 +115,14 @@
             exc_data.exc_type = etype
             exc_data.exc_value = evalue
             lloperation.llop.debug_start_traceback(lltype.Void, etype)
-            if register.register_number is not None:
+            if use_special_reg:
                 register.store_into_reg(llmemory.NULL)
 
         def rpyexc_reraise(etype, evalue):
             exc_data.exc_type = etype
             exc_data.exc_value = evalue
             lloperation.llop.debug_reraise_traceback(lltype.Void, etype)
-            if register.register_number is not None:
+            if use_special_reg:
                 register.store_into_reg(llmemory.NULL)
 
         def rpyexc_fetch_exception():
@@ -131,7 +134,7 @@
             if evalue:
                 exc_data.exc_type = rclass.ll_inst_type(evalue)
                 exc_data.exc_value = evalue
-                if register.register_number is not None:
+                if use_special_reg:
                     register.store_into_reg(llmemory.NULL)
 
         def rpyexc_raise_stack_overflow():
@@ -428,7 +431,7 @@
         #
         self.gen_setfield('exc_value', self.c_null_evalue, llops)
         self.gen_setfield('exc_type',  self.c_null_etype,  llops)
-        if register.register_number is not None:
+        if self.use_special_reg:
             self.gen_setspecialregister(self.c_nonnull_specialregister, llops)
         excblock.operations[:] = llops
         newgraph.exceptblock.inputargs[0].concretetype = self.lltype_of_exception_type
@@ -453,11 +456,11 @@
         if alloc_shortcut:
             T = spaceop.result.concretetype
             var_no_exc = self.gen_nonnull(spaceop.result, llops)
-        elif register.register_number is None:
+        elif self.use_special_reg:
+            var_no_exc = self.gen_specialreg_no_exc(llops)
+        else:
             v_exc_type = self.gen_getfield('exc_type', llops)
             var_no_exc = self.gen_isnull(v_exc_type, llops)
-        else:
-            var_no_exc = self.gen_specialreg_no_exc(llops)
 
         block.operations.extend(llops)
         
@@ -647,10 +650,10 @@
     def build_extra_funcs(self):
         pass
 
-def ExceptionTransformer(translator):
+def ExceptionTransformer(translator, standalone):
     type_system = translator.rtyper.type_system.name
     if type_system == 'lltypesystem':
-        return LLTypeExceptionTransformer(translator)
+        return LLTypeExceptionTransformer(translator, standalone)
     else:
         assert type_system == 'ootypesystem'
-        return OOTypeExceptionTransformer(translator)
+        return OOTypeExceptionTransformer(translator, standalone)
diff --git a/pypy/translator/translator.py b/pypy/translator/translator.py
--- a/pypy/translator/translator.py
+++ b/pypy/translator/translator.py
@@ -108,13 +108,14 @@
                                    type_system = type_system)
         return self.rtyper
 
-    def getexceptiontransformer(self):
+    def getexceptiontransformer(self, standalone):
         if self.rtyper is None:
             raise ValueError("no rtyper")
         if self.exceptiontransformer is not None:
+            assert self.exceptiontransformer.standalone == standalone
             return self.exceptiontransformer
         from pypy.translator.exceptiontransform import ExceptionTransformer
-        self.exceptiontransformer = ExceptionTransformer(self)
+        self.exceptiontransformer = ExceptionTransformer(self, standalone)
         return self.exceptiontransformer
 
     def checkgraphs(self):