diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f4da603a967..efe3238c757 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2005-01-08 Roger Sayle + + * ifcvt.c (find_if_case_1): Reinstate 2005-01-04 change, now that + the latent bug in rtl_delete_block has been resolved. + 2005-01-08 Richard Sandiford * config/mips/t-iris6 (MULTILIB_DIRNAMES): Use -mabi argument values. diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 98fbd667a01..5eea041d404 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -2927,7 +2927,22 @@ find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge) else_bb->global_live_at_start, then_bb->global_live_at_end); - new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb), else_bb); + + /* We can avoid creating a new basic block if then_bb is immediately + followed by else_bb, i.e. deleting then_bb allows test_bb to fall + thru to else_bb. */ + + if (then_bb->next_bb == else_bb + && then_bb->prev_bb == test_bb + && else_bb != EXIT_BLOCK_PTR) + { + redirect_edge_succ (FALLTHRU_EDGE (test_bb), else_bb); + new_bb = 0; + } + else + new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb), + else_bb); + then_bb_index = then_bb->index; delete_basic_block (then_bb);