[Bug optimization/15385] New: [3.5 regression] ICE in spill_failure

[Bug optimization/15385] New: [3.5 regression] ICE in spill_failure

[bangerth at dealii dot org]

With this little testcase 
---------------------- 
int foo(); 
 
void bar () { 
  int n = foo(); 
  double d; 
 
  if (d==0) 
    for (int i=0; i<n; ++i) 
      d = 1.; 
} 
----------------------- 
 
I get this with mainline: 
 
g/x> /home/bangerth/bin/gcc-3.5-pre/bin/c++ -O2 -funroll-loops -c x.cc 
x.cc: In function `void bar()': 
x.cc:10: error: unable to find a register to spill in class `AREG' 
x.cc:10: error: this is the insn: 
(jump_insn:HI 25 24 72 0 (parallel [ 
            (set (pc) 
                (if_then_else (ne (reg/v:DF 59 [ d ]) 
                        (reg:DF 8 st [60])) 
                    (label_ref 69) 
                    (pc))) 
            (clobber (reg:CCFP 18 fpsr)) 
            (clobber (reg:CCFP 17 flags)) 
            (clobber (scratch:HI)) 
        ]) 355 {*fp_jcc_5} (insn_list 24 (nil)) 
    (expr_list:REG_UNUSED (scratch:HI) 
        (expr_list:REG_UNUSED (reg:CCFP 17 flags) 
            (expr_list:REG_UNUSED (reg:CCFP 18 fpsr) 
                (expr_list:REG_DEAD (reg/v:DF 59 [ d ]) 
                    (expr_list:REG_DEAD (reg:DF 8 st [60]) 
                        (expr_list:REG_UNUSED (scratch:HI) 
                            (expr_list:REG_UNUSED (reg:CCFP 17 flags) 
                                (expr_list:REG_UNUSED (reg:CCFP 18 fpsr) 
                                    (expr_list:REG_BR_PROB (const_int 5000 [0x1388]) 
                                        (nil))))))))))) 
x.cc:10: internal compiler error: in spill_failure, at reload1.c:1887 
Please submit a full bug report, 
with preprocessed source if appropriate. 
See <URL:http://gcc.gnu.org/bugs.html> for instructions. 
 
That's a regression against 3.4 that didn't ICE. Note that my mainline version is 
slightly outdated: 
 
g/x> /home/bangerth/bin/gcc-3.5-pre/bin/c++ -v 
Reading specs from /home/bangerth/bin/gcc-3.5-pre/lib/gcc/i686-pc-linux-gnu/3.5.0/specs 
Configured with: ../gcc-3.5/configure --prefix=/home/bangerth/bin/gcc-3.5-pre --enable-checking 
--enable-languages=c,c++,f77 
Thread model: posix 
gcc version 3.5.0 20040421 (experimental) 
 
Someone may be able to confirm with a newer version. 
 
W.

-- 
           Summary: [3.5 regression] ICE in spill_failure
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bangerth at dealii dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-11 20:26 -------
Confirmed, still happens as of today.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
      Known to fail|                            |3.5.0 tree-ssa
      Known to work|                            |3.4.0
   Last reconfirmed|0000-00-00 00:00:00         |2004-05-11 20:26:55
               date|                            |
   Target Milestone|---                         |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-11 20:32 -------
Here is a better example which does not use an uninitailized variable and still ICEs:
int foo();

void bar (double d) {
  int n = foo();

  if (d==0)
    for (int i=0; i<n; ++i)
        ;
}

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-12 13:07 -------
Here is another sample of what is ICEing (derived from the tree-ssa's tree dump):
int foo();
void bar (double d) {
  int i;
  int n;

  n = foo ();
  if (d == 0.0) goto L6; else goto L3;
L6:;
  if (n > 0) goto L13; else goto L3;
L13:;
  i = 0;
L1:;
  i = i + 1;
  if (i < n) goto L1; else goto L3;
L3:;
  return;
}

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-12 13:10 -------
Also only -O1 -funroll-loops is needed to reproduce the ICE.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-12 19:30 -------
*** Bug 15404 has been marked as a duplicate of this bug. ***

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ludovic dot brenta at
                   |                            |insalien dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385

[Bug rtl-optimization/15385] [3.5 regression] ICE in spill_failure

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-08-03 06:16 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15385