From 7d906d07ed736abc854db2e770d5e5e07730581c Mon Sep 17 00:00:00 2001 From: Segher Boessenkool Date: Tue, 24 Nov 2015 07:43:20 +0100 Subject: [PATCH] combine: Handle aborts in is_parallel_of_n_reg_sets (PR68381) Some users of is_parallel_of_n_reg_sets disregard the clobbers in a parallel after it has returned "yes, this is a parallel of N sets and maybe some clobbers". But combine uses a clobber of const0_rtx to indicate substitution failure, so this leads to disaster. Fix this by checking for such special clobbers in is_parallel_of_n_reg_sets. PR rtl-optimization/68381 * combine.c (is_parallel_of_n_reg_sets): Return false if the pattern is poisoned. From-SVN: r230786 --- gcc/ChangeLog | 6 ++++++ gcc/combine.c | 3 ++- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index e770638354d..b3538c48735 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2015-11-24 Segher Boessenkool + + PR rtl-optimization/68381 + * combine.c (is_parallel_of_n_reg_sets): Return false if the pattern + is poisoned. + 2015-11-23 Nick Clifton Jeff Law diff --git a/gcc/combine.c b/gcc/combine.c index 2a66fd5c8bd..4958d3bfc63 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -2512,7 +2512,8 @@ is_parallel_of_n_reg_sets (rtx pat, int n) || !REG_P (SET_DEST (XVECEXP (pat, 0, i)))) return false; for ( ; i < len; i++) - if (GET_CODE (XVECEXP (pat, 0, i)) != CLOBBER) + if (GET_CODE (XVECEXP (pat, 0, i)) != CLOBBER + || XEXP (XVECEXP (pat, 0, i), 0) == const0_rtx) return false; return true; -- 2.30.2