[pypy-commit] pypy default: Remove a guard_no_exception() at the start of the loop too.

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r46044:2cfe0f51122b
Date: 2011-07-28 11:14 +0200
http://bitbucket.org/pypy/pypy/changeset/2cfe0f51122b/

Log:	Remove a guard_no_exception() at the start of the loop too.

diff --git a/pypy/jit/metainterp/optimizeopt/__init__.py b/pypy/jit/metainterp/optimizeopt/__init__.py
--- a/pypy/jit/metainterp/optimizeopt/__init__.py
+++ b/pypy/jit/metainterp/optimizeopt/__init__.py
@@ -55,7 +55,7 @@
 
 
 def optimize_loop_1(metainterp_sd, loop, enable_opts,
-                    inline_short_preamble=True, retraced=False):
+                    inline_short_preamble=True, retraced=False, bridge=False):
     """Optimize loop.operations to remove internal overheadish operations.
     """
 
@@ -64,7 +64,7 @@
     if unroll:
         optimize_unroll(metainterp_sd, loop, optimizations)
     else:
-        optimizer = Optimizer(metainterp_sd, loop, optimizations)
+        optimizer = Optimizer(metainterp_sd, loop, optimizations, bridge)
         optimizer.propagate_all_forward()
 
 def optimize_bridge_1(metainterp_sd, bridge, enable_opts,
@@ -76,7 +76,7 @@
     except KeyError:
         pass
     optimize_loop_1(metainterp_sd, bridge, enable_opts,
-                    inline_short_preamble, retraced)
+                    inline_short_preamble, retraced, bridge=True)
 
 if __name__ == '__main__':
     print ALL_OPTS_NAMES
diff --git a/pypy/jit/metainterp/optimizeopt/optimizer.py b/pypy/jit/metainterp/optimizeopt/optimizer.py
--- a/pypy/jit/metainterp/optimizeopt/optimizer.py
+++ b/pypy/jit/metainterp/optimizeopt/optimizer.py
@@ -248,10 +248,11 @@
 
 class Optimizer(Optimization):
 
-    def __init__(self, metainterp_sd, loop, optimizations=None):
+    def __init__(self, metainterp_sd, loop, optimizations=None, bridge=False):
         self.metainterp_sd = metainterp_sd
         self.cpu = metainterp_sd.cpu
         self.loop = loop
+        self.bridge = bridge
         self.values = {}
         self.interned_refs = self.cpu.ts.new_ref_dict()
         self.resumedata_memo = resume.ResumeDataLoopMemo(metainterp_sd)
@@ -407,9 +408,7 @@
             return CVAL_ZERO
 
     def propagate_all_forward(self):
-        self.exception_might_have_happened = True
-        # ^^^ at least at the start of bridges.  For loops, we could set
-        # it to False, but we probably don't care
+        self.exception_might_have_happened = self.bridge
         self.newoperations = []
         self.first_optimization.propagate_begin_forward()
         self.i = 0
diff --git a/pypy/jit/metainterp/optimizeopt/test/test_optimizebasic.py b/pypy/jit/metainterp/optimizeopt/test/test_optimizebasic.py
--- a/pypy/jit/metainterp/optimizeopt/test/test_optimizebasic.py
+++ b/pypy/jit/metainterp/optimizeopt/test/test_optimizebasic.py
@@ -693,7 +693,6 @@
         """
         expected = """
         [i]
-        guard_no_exception() []
         i1 = int_add(i, 3)
         i2 = call(i1, descr=nonwritedescr)
         guard_no_exception() [i1, i2]
diff --git a/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py b/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
--- a/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
+++ b/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
@@ -889,12 +889,10 @@
         i3 = call(i2, descr=nonwritedescr)
         jump(i1)       # the exception is considered lost when we loop back
         """
-        # note that 'guard_no_exception' at the very start must be kept
-        # around: bridges may start with one.  (In case of loops we could
-        # remove it, but we probably don't care.)
+        # note that 'guard_no_exception' at the very start is kept around
+        # for bridges, but not for loops
         preamble = """
         [i]
-        guard_no_exception() []
         i1 = int_add(i, 3)
         i2 = call(i1, descr=nonwritedescr)
         guard_no_exception() [i1, i2]
@@ -2993,6 +2991,38 @@
         '''
         self.optimize_loop(ops, expected, preamble, call_pure_results)
 
+    def test_call_pure_constant_folding_exc(self):
+        # CALL_PURE may be followed by GUARD_NO_EXCEPTION
+        arg_consts = [ConstInt(i) for i in (123456, 4, 5, 6)]
+        call_pure_results = {tuple(arg_consts): ConstInt(42)}
+        ops = '''
+        [i0, i1, i2]
+        escape(i1)
+        escape(i2)
+        i3 = call_pure(123456, 4, 5, 6, descr=plaincalldescr)
+        guard_no_exception() []
+        i4 = call_pure(123456, 4, i0, 6, descr=plaincalldescr)
+        guard_no_exception() []
+        jump(i0, i3, i4)
+        '''
+        preamble = '''
+        [i0, i1, i2]
+        escape(i1)
+        escape(i2)
+        i4 = call(123456, 4, i0, 6, descr=plaincalldescr)
+        guard_no_exception() []
+        jump(i0, i4)
+        '''
+        expected = '''
+        [i0, i2]
+        escape(42)
+        escape(i2)
+        i4 = call(123456, 4, i0, 6, descr=plaincalldescr)
+        guard_no_exception() []
+        jump(i0, i4)
+        '''
+        self.optimize_loop(ops, expected, preamble, call_pure_results)
+
     # ----------
 
     def test_vref_nonvirtual_nonescape(self):