[PATCH] Fix missing EH updates in execute_cse_sincos (PR tree-optimization/54563)

[Jakub Jelinek]

Hi!

As discussed in the PR, this patch fixes the ICE by calling
gimple_purge_dead_eh_edges if the last stmt has been replaced by the pass.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

Still, I think it would be nice if e.g. powf or cosl were throw() in C++, at
least if they are treated as builtins or at least in C++11 where they are
library functions.

2012-09-16  Jakub Jelinek  <ja...@redhat.com>

        PR tree-optimization/54563
        * tree-ssa-math-opts.c (execute_cse_sincos): Call
        gimple_purge_dead_eh_edges if last call has been changed.

        * g++.dg/torture/pr54563.C: New test.

--- gcc/tree-ssa-math-opts.c.jj 2012-09-12 10:57:02.000000000 +0200
+++ gcc/tree-ssa-math-opts.c    2012-09-14 21:03:05.546319590 +0200
@@ -1378,12 +1378,18 @@ execute_cse_sincos (void)
   FOR_EACH_BB (bb)
     {
       gimple_stmt_iterator gsi;
+      bool cleanup_eh = false;
 
       for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
         {
          gimple stmt = gsi_stmt (gsi);
          tree fndecl;
 
+         /* Only the last stmt in a bb could throw, no need to call
+            gimple_purge_dead_eh_edges if we change something in the middle
+            of a basic block.  */
+         cleanup_eh = false;
+
          if (is_gimple_call (stmt)
              && gimple_call_lhs (stmt)
              && (fndecl = gimple_call_fndecl (stmt))
@@ -1421,6 +1427,7 @@ execute_cse_sincos (void)
                      gimple_set_location (new_stmt, loc);
                      unlink_stmt_vdef (stmt);
                      gsi_replace (&gsi, new_stmt, true);
+                     cleanup_eh = true;
                      if (gimple_vdef (stmt))
                        release_ssa_name (gimple_vdef (stmt));
                    }
@@ -1443,6 +1450,7 @@ execute_cse_sincos (void)
                      gimple_set_location (new_stmt, loc);
                      unlink_stmt_vdef (stmt);
                      gsi_replace (&gsi, new_stmt, true);
+                     cleanup_eh = true;
                      if (gimple_vdef (stmt))
                        release_ssa_name (gimple_vdef (stmt));
                    }
@@ -1460,6 +1468,7 @@ execute_cse_sincos (void)
                      gimple_set_location (new_stmt, loc);
                      unlink_stmt_vdef (stmt);
                      gsi_replace (&gsi, new_stmt, true);
+                     cleanup_eh = true;
                      if (gimple_vdef (stmt))
                        release_ssa_name (gimple_vdef (stmt));
                    }
@@ -1469,6 +1478,8 @@ execute_cse_sincos (void)
                }
            }
        }
+      if (cleanup_eh)
+       cfg_changed |= gimple_purge_dead_eh_edges (bb);
     }
 
   statistics_counter_event (cfun, "sincos statements inserted",
--- gcc/testsuite/g++.dg/torture/pr54563.C.jj   2012-09-14 21:05:07.514702413 
+0200
+++ gcc/testsuite/g++.dg/torture/pr54563.C      2012-09-14 21:04:40.000000000 
+0200
@@ -0,0 +1,14 @@
+// PR tree-optimization/54563
+// { dg-do compile }
+
+extern "C" float powf (float, float);
+struct S { ~S (); };
+double bar ();
+double x;
+
+void
+foo ()
+{
+  S s;
+  x = powf (bar (), 2.);
+}

        Jakub