PR tree-optimization/40676

	* tree-ssa-dce.c (eliminate_unnecessary_stmts): Do renaming on all
	virtual PHIs in empty BBs.

	* gcc.c-torture/compile/pr40676.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@149789 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8ad42bf..c88b30b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2009-07-19  Jan Hubicka  <jh@suse.cz>
+
+       PR tree-optimization/40676
+       * tree-ssa-dce.c (eliminate_unnecessary_stmts): Do renaming on all
+       virtual PHIs in empty BBs.
+
 2009-07-18  Adam Nemet  <anemet@caviumnetworks.com>
 
        * combine.c (make_compound_operation) <SUBREG>: If force_to_mode

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b1f8698..6951c22 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-07-19  Jan Hubicka  <jh@suse.cz>
+
+       PR tree-optimization/40676
+       * gcc.c-torture/compile/pr40676.c: New testcase.
+
 2009-07-18  Adam Nemet  <anemet@caviumnetworks.com>
 
        * gcc.target/mips/ext-2.c: New test.

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr40676.c b/gcc/testsuite/gcc.c-torture/compile/pr40676.c
new file mode 100644 (file)
index 0000000..b042628
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr40676.c
@@ -0,0 +1,33 @@
+extern int f1();
+extern int f2(void*);
+extern void* f3(int);
+int xmsih;
+typedef unsigned short XWCHAR;
+
+inline unsigned int xstrlenW( const XWCHAR *str )
+{
+    const XWCHAR *s = str;
+    while (*s) s++;
+    return s - str;
+}
+
+
+static int msi_dialog_register_class( void )
+{
+    int cls;
+
+    if( !f2( &cls ) )
+        return 0;
+    if( !f2( &cls ) )
+        return 0;
+    xmsih = f1();
+    if( !xmsih )
+        return 0;
+    return 1;
+}
+
+void *xmsi_dialog_create(const XWCHAR* szDialogName)
+{
+    msi_dialog_register_class();
+    return f3(xstrlenW(szDialogName));
+}

diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c
index fdfdda5..86134ad 100644 (file)
--- a/gcc/tree-ssa-dce.c
+++ b/gcc/tree-ssa-dce.c
@@ -1137,7 +1137,8 @@ eliminate_unnecessary_stmts (void)
       for (bb = ENTRY_BLOCK_PTR->next_bb; bb != EXIT_BLOCK_PTR; bb = next_bb)
        {
          next_bb = bb->next_bb;
-         if (!(bb->flags & BB_REACHABLE))
+         if (!TEST_BIT (bb_contains_live_stmts, bb->index)
+             || !(bb->flags & BB_REACHABLE))
            {
              for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
                if (!is_gimple_reg (gimple_phi_result (gsi_stmt (gsi))))
@@ -1159,7 +1160,8 @@ eliminate_unnecessary_stmts (void)
                    if (found)
                      mark_virtual_phi_result_for_renaming (gsi_stmt (gsi));
                  }
-             delete_basic_block (bb);
+             if (!(bb->flags & BB_REACHABLE))
+               delete_basic_block (bb);
            }
        }
     }