diff options
| author | bstarynk <bstarynk@138bc75d-0d04-0410-961f-82ee72b054a4> | 2008-10-10 10:21:31 +0000 |
|---|---|---|
| committer | bstarynk <bstarynk@138bc75d-0d04-0410-961f-82ee72b054a4> | 2008-10-10 10:21:31 +0000 |
| commit | 18a8d8ef31080fb83c7706fcc32e01c5054e019d (patch) | |
| tree | b081f5bedd4bbb3b5b431946e31f82948a6efb09 /gcc/cse.c | |
| parent | 7e59625d1a6f3ec0132cbb4e83530fd9df32b887 (diff) | |
| download | gcc-18a8d8ef31080fb83c7706fcc32e01c5054e019d.tar.gz | |
2008-10-10 Basile Starynkevitch <basile@starynkevitch.net>
MELT branch merged with trunk r141021
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@141032 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/cse.c')
| -rw-r--r-- | gcc/cse.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/gcc/cse.c b/gcc/cse.c index b911879bf79..f4bd77e4700 100644 --- a/gcc/cse.c +++ b/gcc/cse.c @@ -1,6 +1,6 @@ /* Common subexpression elimination for GNU compiler. Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998 - 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 + 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc. This file is part of GCC. @@ -603,7 +603,8 @@ static bool set_live_p (rtx, rtx, int *); static int cse_change_cc_mode (rtx *, void *); static void cse_change_cc_mode_insn (rtx, rtx); static void cse_change_cc_mode_insns (rtx, rtx, rtx); -static enum machine_mode cse_cc_succs (basic_block, rtx, rtx, bool); +static enum machine_mode cse_cc_succs (basic_block, basic_block, rtx, rtx, + bool); #undef RTL_HOOKS_GEN_LOWPART @@ -6587,13 +6588,17 @@ cse_change_cc_mode_insns (rtx start, rtx end, rtx newreg) permitted to change the mode of CC_SRC to a compatible mode. This returns VOIDmode if no equivalent assignments were found. Otherwise it returns the mode which CC_SRC should wind up with. + ORIG_BB should be the same as BB in the outermost cse_cc_succs call, + but is passed unmodified down to recursive calls in order to prevent + endless recursion. The main complexity in this function is handling the mode issues. We may have more than one duplicate which we can eliminate, and we try to find a mode which will work for multiple duplicates. */ static enum machine_mode -cse_cc_succs (basic_block bb, rtx cc_reg, rtx cc_src, bool can_change_mode) +cse_cc_succs (basic_block bb, basic_block orig_bb, rtx cc_reg, rtx cc_src, + bool can_change_mode) { bool found_equiv; enum machine_mode mode; @@ -6624,7 +6629,9 @@ cse_cc_succs (basic_block bb, rtx cc_reg, rtx cc_src, bool can_change_mode) continue; if (EDGE_COUNT (e->dest->preds) != 1 - || e->dest == EXIT_BLOCK_PTR) + || e->dest == EXIT_BLOCK_PTR + /* Avoid endless recursion on unreachable blocks. */ + || e->dest == orig_bb) continue; end = NEXT_INSN (BB_END (e->dest)); @@ -6729,7 +6736,7 @@ cse_cc_succs (basic_block bb, rtx cc_reg, rtx cc_src, bool can_change_mode) { enum machine_mode submode; - submode = cse_cc_succs (e->dest, cc_reg, cc_src, false); + submode = cse_cc_succs (e->dest, orig_bb, cc_reg, cc_src, false); if (submode != VOIDmode) { gcc_assert (submode == mode); @@ -6857,7 +6864,7 @@ cse_condition_code_reg (void) the basic block. */ orig_mode = GET_MODE (cc_src); - mode = cse_cc_succs (bb, cc_reg, cc_src, true); + mode = cse_cc_succs (bb, bb, cc_reg, cc_src, true); if (mode != VOIDmode) { gcc_assert (mode == GET_MODE (cc_src)); |