diff options
| author | segher <segher@138bc75d-0d04-0410-961f-82ee72b054a4> | 2016-02-04 23:09:51 +0000 |
|---|---|---|
| committer | segher <segher@138bc75d-0d04-0410-961f-82ee72b054a4> | 2016-02-04 23:09:51 +0000 |
| commit | 81c08ac38543d80cdcb2601ce2d00e72ab946490 (patch) | |
| tree | 0fdcad95e5f8873a1ee2cf85e01b7094f22cdd2e | |
| parent | f7ef53928bc90411d40404ce42dc2c3dfc33c2fb (diff) | |
| download | gcc-81c08ac38543d80cdcb2601ce2d00e72ab946490.tar.gz | |
combine: distribute_notes again (PR69567, PR64682)
As it happens the patch I did over a year ago for PR64682 isn't quite
correct. This is PR69567. This fixes it.
PR rtl-optimization/64682
PR rtl-optimization/69567
* combine.c (distribute_notes) <REG_DEAD>: Place the death note
before I2 only if the register is both used and set in I2.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@233159 138bc75d-0d04-0410-961f-82ee72b054a4
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/combine.c | 16 |
2 files changed, 16 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 17e4f49182b..a6ec06ff047 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2016-02-04 Segher Boessenkool <segher@kernel.crashing.org> + + PR rtl-optimization/64682 + PR rtl-optimization/69567 + * combine.c (distribute_notes) <REG_DEAD>: Place the death note + before I2 only if the register is both used and set in I2. + 2016-02-04 DJ Delorie <dj@redhat.com> * config/msp430/msp430.c (msp430_start_function): Add function type. diff --git a/gcc/combine.c b/gcc/combine.c index c307793a495..3609b946188 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -13901,6 +13901,7 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2, tem_insn = from_insn; else { + tem_insn = i3; if (from_insn && CALL_P (from_insn) && find_reg_fusage (from_insn, USE, XEXP (note, 0))) @@ -13909,7 +13910,14 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2, place = i3; else if (i2 != 0 && next_nonnote_nondebug_insn (i2) == i3 && reg_referenced_p (XEXP (note, 0), PATTERN (i2))) - place = i2; + { + place = i2; + /* If the new I2 sets the same register that is marked dead + in the note, the note now should not be put on I2, as the + note refers to a previous incarnation of the reg. */ + if (reg_set_p (XEXP (note, 0), PATTERN (i2))) + tem_insn = i2; + } else if ((rtx_equal_p (XEXP (note, 0), elim_i2) && !(i2mod && reg_overlap_mentioned_p (XEXP (note, 0), @@ -13917,12 +13925,6 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2, || rtx_equal_p (XEXP (note, 0), elim_i1) || rtx_equal_p (XEXP (note, 0), elim_i0)) break; - tem_insn = i3; - /* If the new I2 sets the same register that is marked dead - in the note, the note now should not be put on I2, as the - note refers to a previous incarnation of the reg. */ - if (i2 != 0 && reg_set_p (XEXP (note, 0), PATTERN (i2))) - tem_insn = i2; } if (place == 0) |