[Bug target/21501] New: ICE in extract_insn, at recog.c:2082

[Bug target/21501] New: ICE in extract_insn, at recog.c:2082

[belyshev at depni dot sinp dot msu dot ru]

compile this with -O1 (note testcase reduced from real.c):
-------------------------------------------------------------------------------
int foo (int u)
{
  u = u - 67108864 - 128;
  return u;
}
-------------------------------------------------------------------------------

compiler output:

bug.i: In function ‘foo’:
bug.i:5: error: unrecognizable insn:
(insn 11 10 12 1 (set (reg:SI 105)
        (const_int 4227858432 [0xfc000000])) -1 (nil)
    (nil))
bug.i:5: internal compiler error: in extract_insn, at recog.c:2082

-- 
           Summary: ICE in extract_insn, at recog.c:2082
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, build
          Severity: normal
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: belyshev at depni dot sinp dot msu dot ru
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: arm-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] ICE in extract_insn, at recog.c:2082

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |richard dot earnshaw at arm
                   |                            |dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] ICE in extract_insn, at recog.c:2082

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-10 18:38 -------
I almost think this was caused by:
2005-05-09  Richard Earnshaw  <richard.earnshaw@arm.com>

        * arm.c (arm_gen_constant): Add new heuristic for generating
        constant integers that can be expressed as the difference of two
        valid immediates.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] ICE in extract_insn, at recog.c:2082

[rearnsha at gcc dot gnu dot org]

------- Additional Comments From rearnsha at gcc dot gnu dot org  2005-05-11 09:36 -------
This compiles without problems for me with today's compiler:

$ /work/rearnsha/gnu/egcs/gcc/cc1 -O1 diff.c
 foo

Execution times (seconds)
 symout                :   0.00 ( 0%) usr   0.01 (100%) sys   0.01 (50%) wall
 TOTAL                 :   0.01             0.01             0.02
$ cat diff.s
        .file   "diff.c"
        .text
        .align  2
        .global foo
        .type   foo, %function
foo:
        @ args = 0, pretend = 0, frame = 0
        @ frame_needed = 0, uses_anonymous_args = 0
        @ link register save eliminated.
        @ lr needed for prologue
        mov     r3, #-67108864
        sub     r3, r3, #128
        add     r0, r0, r3
        bx      lr
        .size   foo, .-foo
        .ident  "GCC: (GNU) 4.1.0 20050511 (experimental)"

While developing the other patch that I committed at about the same time

2005-05-09  Richard Earnshaw  <richard.earnshaw@arm.com>

        * arm.c (const_ok_for_arm): Use a faster algorithm.

I did find that one of my machines (a netbsd-2.99 based machine with libraries
compiled for an ARMv5 core) had a buggy implementation of ffs(3).  If your
ffs(3) does not correctly determine the bottom bit in a constant, then the code
in const_ok_for_arm may well fail in the manner you describe.  That would be a
host bug, though.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WORKSFORME


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] ICE in extract_insn, at recog.c:2082

[belyshev at depni dot sinp dot msu dot ru]

------- Additional Comments From belyshev at depni dot sinp dot msu dot ru  2005-05-11 22:41 -------
Not fixed, fails on x86_64-unknown-linux-gnu host.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |UNCONFIRMED
   GCC host triplet|                            |x86_64-unknown-linux-gnu
         Resolution|WORKSFORME                  |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] [4.1 regression] ICE in extract_insn, at recog.c:2082

[belyshev at depni dot sinp dot msu dot ru]

------- Additional Comments From belyshev at depni dot sinp dot msu dot ru  2005-05-11 23:13 -------
note reverting patch mentioned in comment #1
(http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/arm/arm.c.diff?cvsroot=gcc&r1=1.454&r2=1.455)
fixes the problem.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-05-11 23:13:11
               date|                            |
            Summary|ICE in extract_insn, at     |[4.1 regression] ICE in
                   |recog.c:2082                |extract_insn, at
                   |                            |recog.c:2082


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] [4.1 regression] ICE in extract_insn, at recog.c:2082

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-05-12 10:36 -------
Subject: Bug 21501

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	rearnsha@gcc.gnu.org	2005-05-12 10:36:15

Modified files:
	gcc            : ChangeLog 
	gcc/config/arm : arm.c 

Log message:
	PR target/21501
	* arm.c (arm_gen_constant): Sign-extend intermediate values when
	synthesizing a constant of the difference of two immediates.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.8743&r2=2.8744
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/arm/arm.c.diff?cvsroot=gcc&r1=1.456&r2=1.457



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] [4.1 regression] ICE in extract_insn, at recog.c:2082

[rearnsha at gcc dot gnu dot org]

------- Additional Comments From rearnsha at gcc dot gnu dot org  2005-05-12 10:40 -------
Now fixed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501

[Bug target/21501] [4.1 regression] ICE in extract_insn, at recog.c:2082

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21501