From 4f25c8fbfd7c6909cb107c2634a92fb0187966fc Mon Sep 17 00:00:00 2001 From: Eric Botcazou Date: Sat, 23 Mar 2013 11:06:21 +0000 Subject: [PATCH] combine.c (try_combine): Adjust comment. * combine.c (try_combine): Adjust comment. Do not add the set of insn #0 if the destination indirectly is set or dies in insn #2. Tidy up code to distribute a new note. From-SVN: r197002 --- gcc/ChangeLog | 6 ++++++ gcc/combine.c | 23 +++++++++++------------ 2 files changed, 17 insertions(+), 12 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a437a634cac..1f04a1db8ec 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2013-03-23 Eric Botcazou + + * combine.c (try_combine): Adjust comment. Do not add the set of + insn #0 if the destination indirectly is set or dies in insn #2. + Tidy up code to distribute a new note. + 2013-03-22 Uros Bizjak * config/i386/i386.md (*movdi_internal): Set prefix_rex attribute diff --git a/gcc/combine.c b/gcc/combine.c index acb74216589..acb4cb4c108 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -2845,13 +2845,13 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx i0, int *new_direct_jump_p, /* See if the SETs in I1 or I2 need to be kept around in the merged instruction: whenever the value set there is still needed past I3. - For the SETs in I2, this is easy: we see if I2DEST dies or is set in I3. + For the SET in I2, this is easy: we see if I2DEST dies or is set in I3. - For the SET in I1, we have two cases: If I1 and I2 independently - feed into I3, the set in I1 needs to be kept around if I1DEST dies + For the SET in I1, we have two cases: if I1 and I2 independently feed + into I3, the set in I1 needs to be kept around unless I1DEST dies or is set in I3. Otherwise (if I1 feeds I2 which feeds I3), the set in I1 needs to be kept around unless I1DEST dies or is set in either - I2 or I3. The same consideration applies to I0. */ + I2 or I3. The same considerations apply to I0. */ added_sets_2 = !dead_or_set_p (i3, i2dest); @@ -2863,8 +2863,9 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx i0, int *new_direct_jump_p, if (i0) added_sets_0 = !(dead_or_set_p (i3, i0dest) - || (i0_feeds_i2_n && dead_or_set_p (i2, i0dest)) - || (i0_feeds_i1_n && dead_or_set_p (i1, i0dest))); + || (i0_feeds_i1_n && dead_or_set_p (i1, i0dest)) + || ((i0_feeds_i2_n || (i0_feeds_i1_n && i1_feeds_i2_n)) + && dead_or_set_p (i2, i0dest))); else added_sets_0 = 0; @@ -4158,14 +4159,12 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx i0, int *new_direct_jump_p, if (i3dest_killed) { + rtx new_note = alloc_reg_note (REG_DEAD, i3dest_killed, NULL_RTX); if (newi2pat && reg_set_p (i3dest_killed, newi2pat)) - distribute_notes (alloc_reg_note (REG_DEAD, i3dest_killed, - NULL_RTX), - NULL_RTX, i2, NULL_RTX, elim_i2, elim_i1, elim_i0); + distribute_notes (new_note, NULL_RTX, i2, NULL_RTX, elim_i2, + elim_i1, elim_i0); else - distribute_notes (alloc_reg_note (REG_DEAD, i3dest_killed, - NULL_RTX), - NULL_RTX, i3, newi2pat ? i2 : NULL_RTX, + distribute_notes (new_note, NULL_RTX, i3, newi2pat ? i2 : NULL_RTX, elim_i2, elim_i1, elim_i0); } -- 2.30.2