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| author | Segher Boessenkool <segher@kernel.crashing.org> | 2014-12-01 19:28:07 +0100 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2014-12-01 19:28:07 +0100 |
| commit | 9838117b0d6537073d830006db15bc981749da97 (patch) | |
| tree | e7c0548ca452a22543189199a5be20d62e411fc8 /gcc | |
| parent | 66d4b012463b627a233bdae5349d27dc7ea5c5bf (diff) | |
| download | gcc-9838117b0d6537073d830006db15bc981749da97.zip gcc-9838117b0d6537073d830006db15bc981749da97.tar.gz gcc-9838117b0d6537073d830006db15bc981749da97.tar.bz2 | |
* combine.c (distribute_links): Handle multiple SETs.
From-SVN: r218242
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/combine.c | 52 |
2 files changed, 41 insertions, 15 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index bd31731..f1e029e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,9 @@ 2014-12-01 Segher Boessenkool <segher@kernel.crashing.org> + * combine.c (distribute_links): Handle multiple SETs. + +2014-12-01 Segher Boessenkool <segher@kernel.crashing.org> + * combine.c (struct insn_link): New field `regno'. (alloc_insn_link): New parameter `regno'. Use it. (find_single_use): Check the new field. diff --git a/gcc/combine.c b/gcc/combine.c index f94d877..afcb91e 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -13817,24 +13817,46 @@ distribute_links (struct insn_link *links) next_link = link->next; - /* If the insn that this link points to is a NOTE or isn't a single - set, ignore it. In the latter case, it isn't clear what we - can do other than ignore the link, since we can't tell which - register it was for. Such links wouldn't be used by combine - anyway. - - It is not possible for the destination of the target of the link to - have been changed by combine. The only potential of this is if we - replace I3, I2, and I1 by I3 and I2. But in that case the - destination of I2 also remains unchanged. */ - - if (NOTE_P (link->insn) - || (set = single_set (link->insn)) == 0) + /* If the insn that this link points to is a NOTE, ignore it. */ + if (NOTE_P (link->insn)) + continue; + + set = 0; + rtx pat = PATTERN (link->insn); + if (GET_CODE (pat) == SET) + set = pat; + else if (GET_CODE (pat) == PARALLEL) + { + int i; + for (i = 0; i < XVECLEN (pat, 0); i++) + { + set = XVECEXP (pat, 0, i); + if (GET_CODE (set) != SET) + continue; + + reg = SET_DEST (set); + while (GET_CODE (reg) == ZERO_EXTRACT + || GET_CODE (reg) == STRICT_LOW_PART + || GET_CODE (reg) == SUBREG) + reg = XEXP (reg, 0); + + if (!REG_P (reg)) + continue; + + if (REGNO (reg) == link->regno) + break; + } + if (i == XVECLEN (pat, 0)) + continue; + } + else continue; reg = SET_DEST (set); - while (GET_CODE (reg) == SUBREG || GET_CODE (reg) == ZERO_EXTRACT - || GET_CODE (reg) == STRICT_LOW_PART) + + while (GET_CODE (reg) == ZERO_EXTRACT + || GET_CODE (reg) == STRICT_LOW_PART + || GET_CODE (reg) == SUBREG) reg = XEXP (reg, 0); /* A LOG_LINK is defined as being placed on the first insn that uses |