[Bug target/20928] New: ICE: unrecognoizable insns

[Bug target/20928] New: ICE: unrecognoizable insns

[aj at gcc dot gnu dot org]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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Compiling clisp with gcc 4 CVS fails with the following ICE.  This is a
regression from GCC 3.3.

$ gcc -fPIC -D_GNU_SOURCE  -W -Wswitch -Wcomment -Wpointer-arith -Wimplicit
-Wreturn-type   -O -DUNICODE -DDYNAMIC_FFI -DDYNAMIC_MODULES -DNO_SIGSEGV -I. -c
spvw.c -save-temps -v
Using built-in specs.
Target: x86_64-suse-linux
Configured with: ../configure --enable-threads=posix --prefix=/usr
--with-local-prefix=/usr/local --infodir=/usr/share/info --mandir=/usr/share/man
--libdir=/usr/lib64 --libexecdir=/usr/lib64
--enable-languages=c,c++,objc,f95,java,ada --enable-checking
--with-gxx-include-dir=/usr/include/c++/4.0.0 --with-slibdir=/lib64
--with-system-zlib --enable-shared --enable-__cxa_atexit
--without-system-libunwind --host=x86_64-suse-linux
Thread model: posix
gcc version 4.0.0 20050410 (prerelease) (SUSE Linux)
 /usr/lib64/gcc/x86_64-suse-linux/4.0.0/cc1 -E -quiet -v -I. -D_GNU_SOURCE
-DUNICODE -DDYNAMIC_FFI -DDYNAMIC_MODULES -DNO_SIGSEGV spvw.c -mtune=k8 -W
-Wswitch -Wcomment -Wpointer-arith -Wimplicit -Wreturn-type -fPIC -O
-fpch-preprocess -o spvw.i
#include "..." search starts here:
#include <...> search starts here:
 .
 /usr/local/include
 /usr/lib64/gcc/x86_64-suse-linux/4.0.0/include
 /usr/lib64/gcc/x86_64-suse-linux/4.0.0/../../../../x86_64-suse-linux/include
 /usr/include
End of search list.
 /usr/lib64/gcc/x86_64-suse-linux/4.0.0/cc1 -fpreprocessed spvw.i -quiet
-dumpbase spvw.c -mtune=k8 -auxbase spvw -O -W -Wswitch -Wcomment
-Wpointer-arith -Wimplicit -Wreturn-type -version -fPIC -o spvw.s
GNU C version 4.0.0 20050410 (prerelease) (SUSE Linux) (x86_64-suse-linux)
        compiled by GNU C version 4.0.0 20050410 (prerelease) (SUSE Linux).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
In file included from spvw.d:25:
lispbibl.d:7430: warning: volatile register variables don’t work as you might wish
In file included from spvw.d:563:
spvw_typealloc.d: In function ‘allocate_vector’:
spvw_typealloc.d:94: error: unrecognizable insn:
(insn 93 92 88 4 (set (reg/f:DI 87)
        (plus:DI (reg:DI 91)
            (const_int 1125899906842624 [0x4000000000000]))) -1
(insn_list:REG_DEP_TRUE 92 (nil))
    (expr_list:REG_DEAD (reg:DI 91)
        (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI
("symbol_tab_data") [flags 0x40] <var_decl 0x2aaaab1cc750 symbol_tab_data>)
                    (const_int 1125899906842624 [0x4000000000000])))
            (nil))))
spvw_typealloc.d:94: internal compiler error: in extract_insn, at recog.c:2060
Please submit a full bug report,
with preprocessed source if appropriate.

-- 
           Summary: ICE: unrecognoizable insns
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: aj at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org,hubicka at gcc dot gnu
                    dot org,matz at suse dot de
 GCC build triplet: x86_64-linux-gnu
  GCC host triplet: x86_64-linux-gnu
GCC target triplet: x86_64-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] ICE: unrecognizable insns

[aj at gcc dot gnu dot org]

------- Additional Comments From aj at gcc dot gnu dot org  2005-04-10 15:08 -------
Created an attachment (id=8579)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=8579&action=view)
Preprocessed source file


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] ICE: unrecognizable insns

[aj at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|ICE: unrecognoizable insns  |ICE: unrecognizable insns


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 16:01 -------
Also happens with mainline. 
 
extern struct symbol_tab_ 
{ 
  void *S_nil; 
} symbol_tab_data; 
 
typedef struct 
{ 
  unsigned int length; 
  void *data[0]; 
} s; 
 
void * 
allocate_vector (unsigned int len) 
{ 
  unsigned int need; 
  s *ptr; 
  void *obj; 
  ptr->length = len; 
  void **p = &ptr->data[0]; 
  do { 
    *p++ = ((((unsigned char *) ((&symbol_tab_data.S_nil)) + 
              ((unsigned long int) (((1L << (2)))) << 48)))); 
  } while (!(--len == 0)); 
  return obj; 
} 
 
t.c: In function 'allocate_vector': 
t.c:25: error: unrecognizable insn: 
(insn 56 55 51 0 (set (reg/f:DI 70) 
        (plus:DI (reg:DI 73) 
            (const_int 1125899906842624 [0x4000000000000]))) -1 
(insn_list:REG_DEP_TRUE 55 (nil)) 
    (expr_list:REG_DEAD (reg:DI 73) 
        (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI 
("symbol_tab_data") [flags 0x40] <var_decl 0x2a95a36270 symbol_tab_data>) 
                    (const_int 1125899906842624 [0x4000000000000]))) 
            (nil)))) 
t.c:25: internal compiler error: in extract_insn, at recog.c:2082 
 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-04-10 16:01:50
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 16:03 -------
Needs "-O -mtune=k8 -fPIC" of course.  -fPIC seems to cause the problem. 

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
            Summary|ICE: unrecognizable insns   |[4.0/4.1 regression] ICE:
                   |                            |unrecognizable insns
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 16:08 -------
Double *sigh*. 
The old loop optimizer introduces the offending insn.  From the .loop dump: 
 
Insn 26: regno 70 (life 1), move-insn forces 25 savings 1  moved to 56 
Hoisted regno 74 r/o from (mem/u/c:DI (const:DI (unspec:DI [ 
                (symbol_ref:DI ("symbol_tab_data") [flags 0x40] <var_decl 
0x2a95a36270 symbol_tab_data>) 
            ] 2)) [0 S8 A8]) 
... 
(insn 56 55 51 0 (set (reg/f:DI 70) 
        (plus:DI (reg:DI 73) 
            (const_int 1125899906842624 [0x4000000000000]))) -1 (nil) 
    (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI ("symbol_tab_data") 
[flags 0x40] <var_decl 0x2a95a36270 symbol_tab_data>) 
                (const_int 1125899906842624 [0x4000000000000]))) 
        (nil))) 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 17:24 -------
After CSE1 (t.c.04.cse) we have: 
 
(insn 20 18 22 1 (set (reg:DI 66) 
        (mem/u/c:DI (const:DI (unspec:DI [ 
                        (symbol_ref:DI ("bar") [flags 0x40] <var_decl 
0x2a95a2f000 bar>) 
                    ] 2)) [0 S8 A8])) 81 {*movdi_1_rex64} (nil) 
    (nil)) 
 
(insn 22 20 23 1 (set (reg:DI 68) 
        (const_int 2147483648 [0x80000000])) 81 {*movdi_1_rex64} (nil) 
    (nil)) 
 
(insn 23 22 24 1 (parallel [ 
            (set (reg:DI 67) 
                (plus:DI (reg:DI 66) 
                    (reg:DI 68))) 
            (clobber (reg:CC 17 flags)) 
        ]) 193 {*adddi_1_rex64} (nil) 
    (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI ("bar") [flags 
0x40] <var_decl 0x2a95a2f000 bar>) 
                (const_int 2147483648 [0x80000000]))) 
        (nil))) 
 
but old loop (t.c.06.loop) somehow turns this into: 
 
(insn 45 48 46 0 (set (reg:DI 69) 
        (mem/u/c:DI (const:DI (unspec:DI [ 
                        (symbol_ref:DI ("bar") [flags 0x40] <var_decl 
0x2a95a2f000 bar>) 
                    ] 2)) [0 S8 A8])) -1 (nil) 
    (nil)) 
 
(insn 46 45 41 0 (set (reg/f:DI 67) 
        (plus:DI (reg:DI 69) 
            (const_int 2147483648 [0x80000000]))) -1 (nil) 
    (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI ("bar") [flags 
0x40] <var_decl 0x2a95a2f000 bar>) 
                (const_int 2147483648 [0x80000000]))) 
        (nil))) 
 
Note how we have lost a clobber and turned a reg+reg addition into a reg+imm; 
from: 
(set (reg:DI 66) (mem:DI (const:DI (unspec:DI [(symbol_ref:DI ("bar"))])))) 
(set (reg:DI 68) (const_int 2147483648 [0x80000000])) 
(parallel [ 
  (set (reg:DI 67) (plus:DI (reg:DI 66) (reg:DI 68))) 
  (clobber (reg:CC 17 flags))]) 
 
to: 
(set (reg:DI 69) (mem:DI (const:DI (unspec:DI [(symbol_ref:DI ("bar"))])))) 
(set (reg/f:DI 67) (plus:DI (reg:DI 69) (const_int 2147483648 [0x80000000]))) 
 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 17:39 -------
The offending insn is created by emit_move_insn in loop.c, here: 
2354                start_sequence (); 
2355                emit_move_insn (m->insert_temp ? newreg : m->set_dest, 
2356                                m->set_src); 
2357                seq = get_insns (); 
2358                end_sequence (); 
 
(gdb) p debug_rtx_list (seq, 10) 
(insn 45 0 46 (set (reg:DI 69) 
        (mem/u/c:DI (const:DI (unspec:DI [ 
                        (symbol_ref:DI ("bar") [flags 0x40] <var_decl 
0x2a95a2f000 bar>) 
                    ] 2)) [0 S8 A8])) -1 (nil) 
    (nil)) 
 
(insn 46 45 0 (set (reg/f:DI 67) 
        (plus:DI (reg:DI 69) 
            (const_int 2147483648 [0x80000000]))) -1 (nil) 
    (expr_list:REG_EQUAL (const:DI (plus:DI (symbol_ref:DI ("bar") [flags 
0x40] <var_decl 0x2a95a2f000 bar>) 
                (const_int 2147483648 [0x80000000]))) 
        (nil))) 
 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 17:52 -------
My RTL-fu is way below par, so perhaps this doesn't make sense at all, but... 
 
It seems that emit_move_insn must always produce valid move insns.  So it 
should check that an immediate is a valid PIC operand if -fPIC.  In this case 
I'd say LEGITIMATE_CONSTANT_P is the wrong target macro to use.  So you would 
have this instead: 
 
Index: expr.c 
=================================================================== 
RCS file: /cvs/gcc/gcc/gcc/expr.c,v 
retrieving revision 1.783 
diff -u -3 -p -r1.783 expr.c 
--- expr.c      30 Mar 2005 21:34:23 -0000      1.783 
+++ expr.c      10 Apr 2005 17:51:01 -0000 
@@ -3093,7 +3093,8 @@ emit_move_insn (rtx x, rtx y) 
 
       y_cst = y; 
 
-      if (!LEGITIMATE_CONSTANT_P (y)) 
+      if ((!flag_pic && !LEGITIMATE_CONSTANT_P (y)) 
+          || (flag_pic && !LEGITIMATE_PIC_OPERAND_P (y))) 
        { 
          y = force_const_mem (mode, y); 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 19:03 -------
FWIW, smallest test case I could find: 
 
extern struct bar_t bar; 
void 
foo (void) 
{ 
  void **p; 
  do { 
    *p++ = ((unsigned char *) &bar + ((unsigned long int) 1L << 31)); 
  } while (p); 
} 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-04-10 21:05 -------
Alexandre Oliva pointed out to me that it was probably the expander who 
should produce a proper legitimate insn.  I looked at this some more and 
found that in legitimize_pic_address we do not check if a displacement 
is a valid PIC displacement: 
 
Index: config/i386/i386.c 
=================================================================== 
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.c,v 
retrieving revision 1.807 
diff -u -3 -p -r1.807 i386.c 
--- config/i386/i386.c  9 Apr 2005 17:19:48 -0000       1.807 
+++ config/i386/i386.c  10 Apr 2005 21:01:26 -0000 
@@ -5612,7 +5612,13 @@ legitimize_pic_address (rtx orig, rtx re 
                                             base == reg ? NULL_RTX : reg); 
 
              if (GET_CODE (new) == CONST_INT) 
-               new = plus_constant (base, INTVAL (new)); 
+               { 
+                 if (legitimate_pic_address_disp_p (new)) 
+                   new = plus_constant (base, INTVAL (new)); 
+                 else 
+                   new = gen_rtx_PLUS (Pmode, base, 
+                                       copy_to_mode_reg (Pmode, new)); 
+               } 
              else 
                { 
                  if (GET_CODE (new) == PLUS && CONSTANT_P (XEXP (new, 1))) 
 
This looks to me like much better hack (maybe even a proper fix!) so I'll 
test this to see what happens... 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[mmitchel at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.0                       |4.0.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[aj at gcc dot gnu dot org]

------- Additional Comments From aj at gcc dot gnu dot org  2005-05-21 07:00 -------
Steven, any update on this one?  Would you like to get it assigned to? 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[rth at gcc dot gnu dot org]

------- Additional Comments From rth at gcc dot gnu dot org  2005-06-08 00:08 -------
This patch trivially "fixes" the problem because the argument to 
legitimate_pic_address_disp_p is incorrect, and it will always
return false.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2005-07-06 17:03 -------
Postponed until 4.0.2.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.1                       |4.0.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[mmitchel at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.2                       |4.0.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
  GCC build triplet|x86_64-linux-gnu            |
   GCC host triplet|x86_64-linux-gnu            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928

[Bug target/20928] [4.0/4.1 regression] ICE: unrecognizable insns

[kazu at gcc dot gnu dot org]

------- Comment #13 from kazu at gcc dot gnu dot org  2005-10-10 03:20 -------
The testcase in comment #8 still triggers an ICE if run with -O -mtune=k8
-fPIC.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20928