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From: Henrik Grubbström <grubba@grubba.org>

Date: Thu, 29 Sep 2016 17:25:06 +0200

Subject: [PATCH] Compiler [optimizer]: Disabled some broken peep rules.

Bug-Debian: https://bugs.debian.org/836673

Forwarded: yes

Origin: http://pike-librarian.lysator.liu.se/index.xml?checkins=e0fcf06129c03fb51d6da6b13200232a15df7e0d

These peep hole optimizer rules weren't protected against

negation overflow.

Disabled since INT32_NEG_OVERFLOW() doesn't exist in Pike 7.8.

Cf Pike 7.9.5 and later commit c63deca838788875b37d48a4faa044b5d6cafa0b.

Thanks to Magnus Holmgren for the report.

Potential fix for [LysLysKOM 21868180] (infinite optimizer loop).

---

 src/peep.in | 8 ++++----

 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/peep.in b/src/peep.in

index f32f7cd..9279d77 100644

--- a/src/peep.in

+++ b/src/peep.in

@@ -36,8 +36,8 @@ CONST1 NEGATE : CONST_1

 CONST_1 NEGATE : CONST1

 NUMBER NEGATE : NEG_NUMBER($1a)

 NEG_NUMBER NEGATE : NUMBER ($1a)

-NUMBER [(-$1a) > 0] : NEG_NUMBER (-$1a)

-NEG_NUMBER [(-$1a) >= 0] : NUMBER (-$1a)

+// NUMBER [(-$1a) > 0] : NEG_NUMBER (-$1a)

+// NEG_NUMBER [(-$1a) >= 0] : NUMBER (-$1a)

 NEGATE NEGATE :

 COMPL COMPL :

 NEGATE CONST_1 ADD_INTS : COMPL

@@ -238,8 +238,8 @@ CONST_1 INDEX: NEG_INT_INDEX (1)

 CONST1 INDEX: POS_INT_INDEX (1)

 NUMBER INDEX: POS_INT_INDEX ($1a)

 NEG_NUMBER INDEX: NEG_INT_INDEX ($1a)

-POS_INT_INDEX [$1a < 0]: NEG_INT_INDEX (-$1a)

-NEG_INT_INDEX [-$1a >= 0]: POS_INT_INDEX (-$1a)

+// POS_INT_INDEX [$1a < 0]: NEG_INT_INDEX (-$1a)

+// NEG_INT_INDEX [-$1a >= 0]: POS_INT_INDEX (-$1a)

 BRANCH_WHEN_ZERO BRANCH LABEL ($1a): BRANCH_WHEN_NON_ZERO($2a) LABEL($1a)

 BRANCH_WHEN_NON_ZERO BRANCH LABEL ($1a): BRANCH_WHEN_ZERO($2a) LABEL($1a)

-- 

2.9.3