From ec4836a75da03d1b93df6a9dff3da3b597676ed9 Mon Sep 17 00:00:00 2001 From: Segher Boessenkool Date: Thu, 11 Feb 2016 23:26:35 +0100 Subject: [PATCH] combine: More distribute_notes trouble (PR69737) PR64682 is a problem in distribute_notes, where it has trouble putting a REG_DEAD note for a reg that is set twice in the right spot. My fix for that did the wrong thing for PR69567. And then my attempted fix for that one made PR64682 fail again. Instead, let's just lose the note in such complicated cases, like we already do in certain similar cases. PR rtl-optimization/64682 PR rtl-optimization/69567 PR rtl-optimization/69737 * combine.c (distribute_notes) : If the register is set in I2 as well, just lose it. From-SVN: r233356 --- gcc/ChangeLog | 8 ++++++++ gcc/combine.c | 16 +++++++--------- 2 files changed, 15 insertions(+), 9 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4c17a5caf5d..35f8865d548 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2016-02-11 Segher Boessenkool + + PR rtl-optimization/64682 + PR rtl-optimization/69567 + PR rtl-optimization/69737 + * combine.c (distribute_notes) : If the register is set + in I2 as well, just lose it. + 2016-02-11 Kyrylo Tkachov * config/aarch64/aarch64.c (aarch64_last_printed_arch_string): diff --git a/gcc/combine.c b/gcc/combine.c index 3609b946188..24dcefa0bf6 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -13901,7 +13901,6 @@ 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))) @@ -13910,14 +13909,7 @@ 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; - /* 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; - } + place = i2; else if ((rtx_equal_p (XEXP (note, 0), elim_i2) && !(i2mod && reg_overlap_mentioned_p (XEXP (note, 0), @@ -13925,6 +13917,12 @@ 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, we do not know where to put the note. + Give up. */ + if (i2 != 0 && reg_set_p (XEXP (note, 0), PATTERN (i2))) + break; } if (place == 0) -- 2.30.2