* cfgrtl.c (purge_dead_edges): Correct handling of EDGE_EH.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@53521 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 38654fb..50e7bdd 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2002-05-16  Mark Mitchell  <mark@codesourcery.com>
+
+       * cfgrtl.c (purge_dead_edges): Correct handling of EDGE_EH.
+
 2002-05-16  Nick Clifton  <nickc@cambridge.redhat.com>
 
        * config/arm/arm.c (arm_rtx_costs): Check for RTX being a

diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c
index 9a6661d..844f5df 100644 (file)
--- a/gcc/cfgrtl.c
+++ b/gcc/cfgrtl.c
@@ -2186,17 +2186,26 @@ purge_dead_edges (bb)
  
          e->flags &= ~EDGE_ABNORMAL;
 
-         /* Check purposes we can have edge.  */
-         if ((e->flags & EDGE_FALLTHRU)
-             && any_condjump_p (insn))
+         /* See if this edge is one we should keep.  */
+         if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn))
+           /* A conditional jump can fall through into the next
+              block, so we should keep the edge.  */
            continue;
          else if (e->dest != EXIT_BLOCK_PTR
                   && e->dest->head == JUMP_LABEL (insn))
+           /* If the destination block is the target of the jump,
+              keep the edge.  */
+           continue;
+         else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn))
+           /* If the destination block is the exit block, and this
+              instruction is a return, then keep the edge.  */
            continue;
-         else if (e->dest == EXIT_BLOCK_PTR
-                  && returnjump_p (insn))
+         else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
+           /* Keep the edges that correspond to exceptions thrown by
+              this instruction.  */
            continue;
 
+         /* We do not need this edge.  */
          bb->flags |= BB_DIRTY;
          purged = true;
          remove_edge (e);