On Sat, 7 Sep 2013, Mike Stump wrote:
On Sep 7, 2013, at 12:27 PM, Marc Glisse <marc.gli...@inria.fr> wrote:
Now flag_check_new should probably disable this optimization…
Yes, this why my point.
Ok, here it is (again, no proper testing until bootstrap is fixed)
2013-09-07 Marc Glisse <marc.gli...@inria.fr>
PR c++/19476
gcc/
* fold-const.c (tree_expr_nonzero_warnv_p): Handle operator new.
* tree-vrp.c (gimple_stmt_nonzero_warnv_p, stmt_interesting_for_vrp):
Likewise.
(vrp_visit_stmt): Remove duplicated code.
gcc/testsuite/
* g++.dg/tree-ssa/pr19476-1.C: New file.
* g++.dg/tree-ssa/pr19476-2.C: Likewise.
* g++.dg/tree-ssa/pr19476-3.C: Likewise.
--
Marc GlisseIndex: testsuite/g++.dg/tree-ssa/pr19476-1.C
===================================================================
--- testsuite/g++.dg/tree-ssa/pr19476-1.C (revision 0)
+++ testsuite/g++.dg/tree-ssa/pr19476-1.C (revision 0)
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-ccp1" } */
+
+#include <new>
+
+int f(){
+ return 33 + (0 == new(std::nothrow) int);
+}
+int g(){
+ return 42 + (0 == new int[50]);
+}
+
+/* { dg-final { scan-tree-dump "return 42" "ccp1" } } */
+/* { dg-final { scan-tree-dump-not "return 33" "ccp1" } } */
+/* { dg-final { cleanup-tree-dump "ccp1" } } */
Property changes on: testsuite/g++.dg/tree-ssa/pr19476-1.C
___________________________________________________________________
Added: svn:keywords
+ Author Date Id Revision URL
Added: svn:eol-style
+ native
Index: testsuite/g++.dg/tree-ssa/pr19476-2.C
===================================================================
--- testsuite/g++.dg/tree-ssa/pr19476-2.C (revision 0)
+++ testsuite/g++.dg/tree-ssa/pr19476-2.C (revision 0)
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+#include <new>
+
+int f(){
+ int *p = new(std::nothrow) int;
+ return 33 + (0 == p);
+}
+int g(){
+ int *p = new int[50];
+ return 42 + (0 == p);
+}
+
+/* { dg-final { scan-tree-dump "return 42" "optimized" } } */
+/* { dg-final { scan-tree-dump-not "return 33" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
Property changes on: testsuite/g++.dg/tree-ssa/pr19476-2.C
___________________________________________________________________
Added: svn:keywords
+ Author Date Id Revision URL
Added: svn:eol-style
+ native
Index: testsuite/g++.dg/tree-ssa/pr19476-3.C
===================================================================
--- testsuite/g++.dg/tree-ssa/pr19476-3.C (revision 0)
+++ testsuite/g++.dg/tree-ssa/pr19476-3.C (revision 0)
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -fcheck-new -fdump-tree-optimized" } */
+
+#include <new>
+
+int g(){
+ return 42 + (0 == new int);
+}
+
+/* { dg-final { scan-tree-dump-not "return 42" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
Property changes on: testsuite/g++.dg/tree-ssa/pr19476-3.C
___________________________________________________________________
Added: svn:keywords
+ Author Date Id Revision URL
Added: svn:eol-style
+ native
Index: fold-const.c
===================================================================
--- fold-const.c (revision 202351)
+++ fold-const.c (working copy)
@@ -16171,21 +16171,31 @@ tree_expr_nonzero_warnv_p (tree t, bool
case MODIFY_EXPR:
case BIND_EXPR:
return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
strict_overflow_p);
case SAVE_EXPR:
return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
strict_overflow_p);
case CALL_EXPR:
- return alloca_call_p (t);
+ {
+ tree fn = CALL_EXPR_FN (t);
+ if (TREE_CODE (fn) != ADDR_EXPR) return false;
+ tree fndecl = TREE_OPERAND (fn, 0);
+ if (TREE_CODE (fndecl) != FUNCTION_DECL) return false;
+ if (!flag_check_new
+ && DECL_IS_OPERATOR_NEW (fndecl)
+ && !TREE_NOTHROW (fndecl))
+ return true;
+ return alloca_call_p (t);
+ }
default:
break;
}
return false;
}
/* Return true when T is an address and is known to be nonzero.
Handle warnings about undefined signed overflow. */
Index: tree-vrp.c
===================================================================
--- tree-vrp.c (revision 202351)
+++ tree-vrp.c (working copy)
@@ -1047,21 +1047,29 @@ gimple_assign_nonzero_warnv_p (gimple st
*STRICT_OVERFLOW_P.*/
static bool
gimple_stmt_nonzero_warnv_p (gimple stmt, bool *strict_overflow_p)
{
switch (gimple_code (stmt))
{
case GIMPLE_ASSIGN:
return gimple_assign_nonzero_warnv_p (stmt, strict_overflow_p);
case GIMPLE_CALL:
- return gimple_alloca_call_p (stmt);
+ {
+ tree fndecl = gimple_call_fndecl (stmt);
+ if (!fndecl) return false;
+ if (!flag_check_new
+ && DECL_IS_OPERATOR_NEW (fndecl)
+ && !TREE_NOTHROW (fndecl))
+ return true;
+ return gimple_alloca_call_p (stmt);
+ }
default:
gcc_unreachable ();
}
}
/* Like tree_expr_nonzero_warnv_p, but this function uses value ranges
obtained so far. */
static bool
vrp_stmt_computes_nonzero (gimple stmt, bool *strict_overflow_p)
@@ -6486,21 +6494,22 @@ stmt_interesting_for_vrp (gimple stmt)
tree lhs = gimple_get_lhs (stmt);
/* In general, assignments with virtual operands are not useful
for deriving ranges, with the obvious exception of calls to
builtin functions. */
if (lhs && TREE_CODE (lhs) == SSA_NAME
&& (INTEGRAL_TYPE_P (TREE_TYPE (lhs))
|| POINTER_TYPE_P (TREE_TYPE (lhs)))
&& ((is_gimple_call (stmt)
&& gimple_call_fndecl (stmt) != NULL_TREE
- && DECL_BUILT_IN (gimple_call_fndecl (stmt)))
+ && (DECL_BUILT_IN (gimple_call_fndecl (stmt))
+ || DECL_IS_OPERATOR_NEW (gimple_call_fndecl (stmt))))
|| !gimple_vuse (stmt)))
return true;
}
else if (gimple_code (stmt) == GIMPLE_COND
|| gimple_code (stmt) == GIMPLE_SWITCH)
return true;
return false;
}
@@ -7407,30 +7416,21 @@ vrp_visit_stmt (gimple stmt, edge *taken
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nVisiting statement:\n");
print_gimple_stmt (dump_file, stmt, 0, dump_flags);
fprintf (dump_file, "\n");
}
if (!stmt_interesting_for_vrp (stmt))
gcc_assert (stmt_ends_bb_p (stmt));
else if (is_gimple_assign (stmt) || is_gimple_call (stmt))
- {
- /* In general, assignments with virtual operands are not useful
- for deriving ranges, with the obvious exception of calls to
- builtin functions. */
- if ((is_gimple_call (stmt)
- && gimple_call_fndecl (stmt) != NULL_TREE
- && DECL_BUILT_IN (gimple_call_fndecl (stmt)))
- || !gimple_vuse (stmt))
- return vrp_visit_assignment_or_call (stmt, output_p);
- }
+ return vrp_visit_assignment_or_call (stmt, output_p);
else if (gimple_code (stmt) == GIMPLE_COND)
return vrp_visit_cond_stmt (stmt, taken_edge_p);
else if (gimple_code (stmt) == GIMPLE_SWITCH)
return vrp_visit_switch_stmt (stmt, taken_edge_p);
/* All other statements produce nothing of interest for VRP, so mark
their outputs varying and prevent further simulation. */
FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF)
set_value_range_to_varying (get_value_range (def));
