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| author | Segher Boessenkool <segher@kernel.crashing.org> | 2016-08-15 18:17:21 +0200 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2016-08-15 18:17:21 +0200 |
| commit | 2008be405c16e8b7ca5399fb9e6fb25aa92f03a3 (patch) | |
| tree | 52262637556ee25a677df422ac164d71edacb802 /gcc | |
| parent | 5c578ae4348bddb97991348c2d0a05e3e7d7ad5a (diff) | |
| download | gcc-2008be405c16e8b7ca5399fb9e6fb25aa92f03a3.zip gcc-2008be405c16e8b7ca5399fb9e6fb25aa92f03a3.tar.gz gcc-2008be405c16e8b7ca5399fb9e6fb25aa92f03a3.tar.bz2 | |
lra: A multiple_sets is not a simple_move_p (PR73650)
In the PR we have a PARALLEL of a move and a compare (a "mr." instruction).
The compare is dead, so single_set on it returns just the move. Then,
simple_move_p returns true; but the instruction does need reloads in this
case. This patch solves this by making simple_move_p return false for
every multiple_sets instruction.
PR rtl-optimization/73650
* lra-constraints.c (simple_move_p): If the insn is multiple_sets
it is not a simple move.
From-SVN: r239483
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/lra-constraints.c | 7 |
2 files changed, 13 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index dc7e8cb..fa52700 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2016-08-15 Segher Boessenkool <segher@kernel.crashing.org> + + PR rtl-optimization/73650 + * lra-constraints.c (simple_move_p): If the insn is multiple_sets + it is not a simple move. + 2016-08-15 Martin Liska <mliska@suse.cz> PR driver/72765 diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c index 213e408..053a65a 100644 --- a/gcc/lra-constraints.c +++ b/gcc/lra-constraints.c @@ -3493,6 +3493,13 @@ simple_move_p (void) lra_assert (curr_insn_set != NULL_RTX); dest = SET_DEST (curr_insn_set); src = SET_SRC (curr_insn_set); + + /* If the instruction has multiple sets we need to process it even if it + is single_set. This can happen if one or more of the SETs are dead. + See PR73650. */ + if (multiple_sets (curr_insn)) + return false; + return ((dclass = get_op_class (dest)) != NO_REGS && (sclass = get_op_class (src)) != NO_REGS /* The backend guarantees that register moves of cost 2 |