/* Perform doloop optimizations
- Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation,
+ Inc.
Based on code by Michael P. Hayes (m.hayes@elec.canterbury.ac.nz)
This file is part of GCC.
bool increment_count;
basic_block loop_end = desc->out_edge->src;
enum machine_mode mode;
+ rtx true_prob_val;
jump_insn = BB_END (loop_end);
fputs (" iterations).\n", dump_file);
}
+ /* Get the probability of the original branch. If it exists we would
+ need to update REG_BR_PROB of the new jump_insn. */
+ true_prob_val = find_reg_note (jump_insn, REG_BR_PROB, NULL_RTX);
+
/* Discard original jump to continue loop. The original compare
result may still be live, so it cannot be discarded explicitly. */
delete_insn (jump_insn);
REG_NOTES (jump_insn)
= gen_rtx_EXPR_LIST (REG_NONNEG, NULL_RTX, REG_NOTES (jump_insn));
}
+ /* Update the REG_BR_PROB note. */
+ if (true_prob_val)
+ {
+ /* Seems safer to use the branch probability. */
+ REG_NOTES (jump_insn) =
+ gen_rtx_EXPR_LIST (REG_BR_PROB,
+ GEN_INT (desc->in_edge->probability),
+ REG_NOTES (jump_insn));
+ }
}
/* Process loop described by LOOP validating that the loop is suitable for