[Bug target/67756] New: ICE compiling Linux Kernel fs/namei.c on ARM

[Bug target/67756] New: ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

            Bug ID: 67756
           Summary: ICE compiling Linux Kernel fs/namei.c on ARM
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bernd.edlinger at hotmail dot de
  Target Milestone: ---

arm-linux-gnueabihf-gcc -v
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/home/ed/gnu/arm-linux-gnueabihf-linux64/libexec/gcc/arm-linux-gnueabihf/6.0.0/lto-wrapper
Target: arm-linux-gnueabihf
Configured with: ../gcc-6-20150927/configure
--prefix=/home/ed/gnu/arm-linux-gnueabihf-linux64 --target=arm-linux-gnueabihf
--enable-languages=c,c++,fortran,ada --with-arch=armv7-a --with-tune=cortex-a9
--with-fpu=vfpv3-d16 --with-float=hard
Thread model: posix
gcc version 6.0.0 20150927 (experimental) (GCC) 

arm-linux-gnueabihf-gcc -Wp,-MD,fs/.namei.o.d  -nostdinc -isystem
/home/ed/gnu/arm-linux-gnueabihf-linux64/lib/gcc/arm-linux-gnueabihf/6.0.0/include
-I./arch/arm/include -Iarch/arm/include/generated  -Iinclude
-I./arch/arm/include/uapi -Iarch/arm/include/generated/uapi -I./include/uapi
-Iinclude/generated/uapi -include ./include/linux/kconfig.h -D__KERNEL__
-mlittle-endian -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs
-fno-strict-aliasing -fno-common -Werror-implicit-function-declaration
-Wno-format-security -std=gnu89 -fno-dwarf2-cfi-asm -fno-omit-frame-pointer
-mapcs -mno-sched-prolog -mabi=aapcs-linux -mno-thumb-interwork -mfpu=vfp
-funwind-tables -marm -D__LINUX_ARM_ARCH__=7 -march=armv7-a -msoft-float -Uarm
-fno-delete-null-pointer-checks -O2 --param=allow-store-data-races=0
-Wframe-larger-than=1024 -fstack-protector -Wno-unused-but-set-variable
-fno-omit-frame-pointer -fno-optimize-sibling-calls
-fno-var-tracking-assignments -g -pg -Wdeclaration-after-statement
-Wno-pointer-sign -fno-strict-overflow -fconserve-stack -Werror=implicit-int
-Werror=strict-prototypes -Werror=date-time -DCC_HAVE_ASM_GOTO   
-D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(namei)" 
-D"KBUILD_MODNAME=KBUILD_STR(namei)" -c -o fs/namei.o fs/namei.c
fs/namei.c: In function 'vfs_link':
fs/namei.c:3934:1: error: insn does not satisfy its constraints:
 }
 ^
(insn 85 281 86 12 (parallel [
            (set (reg/v:SI 1 r1 [orig:113 max_links ] [113])
                (and:SI (ne:SI (reg/v:SI 1 r1 [orig:113 max_links ] [113])
                        (const_int 0 [0]))
                    (leu:SI (reg/v:SI 1 r1 [orig:113 max_links ] [113])
                        (reg:SI 2 r2 [orig:125 _25 ] [125]))))
            (clobber (reg:CC 100 cc))
        ]) fs/namei.c:3917 262 {*and_scc_scc_nodom}
     (nil))
fs/namei.c:3934:1: internal compiler error: in extract_constrain_insn, at
recog.c:2200
0xa3db48 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc-6-20150927/gcc/rtl-error.c:109
0xa3db6f _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
        ../../gcc-6-20150927/gcc/rtl-error.c:120
0xa1028d extract_constrain_insn(rtx_insn*)
        ../../gcc-6-20150927/gcc/recog.c:2200
0x9efc9d reload_cse_simplify_operands
        ../../gcc-6-20150927/gcc/postreload.c:408
0x9f29b5 reload_cse_simplify
        ../../gcc-6-20150927/gcc/postreload.c:194
0x9f29b5 reload_cse_regs_1
        ../../gcc-6-20150927/gcc/postreload.c:233
0x9f2acb reload_cse_regs
        ../../gcc-6-20150927/gcc/postreload.c:81
0x9f2acb execute
        ../../gcc-6-20150927/gcc/postreload.c:2350
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug target/67756] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #1 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
Created attachment 36411
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36411&action=edit
preprocessed source file

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |6.0
            Summary|ICE compiling Linux Kernel  |[6 Regression] ICE
                   |fs/namei.c on ARM           |compiling Linux Kernel
                   |                            |fs/namei.c on ARM

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ktkachov at gcc dot gnu.org

--- Comment #2 from ktkachov at gcc dot gnu.org ---
Created attachment 36412
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36412&action=edit
Reduced testcase

Confirmed.
Attaching reduced testcase. Needs -O2 -mapcs

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-09-29
     Ever confirmed|0                           |1

--- Comment #3 from ktkachov at gcc dot gnu.org ---
Changing status...

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #4 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
necessary compiler options to trigger the ICE: -O2 and -mapcs
arm-linux-gnueabihf-gcc -O2 -mapcs -S kernel-ice.c

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

Bernd Edlinger <bernd.edlinger at hotmail dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vmakarov at redhat dot com

--- Comment #5 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
kernel-ice.c.231r.ira:
(insn 47 45 48 6 (parallel [
            (set (reg:SI 138)
                (and:SI (ne:SI (reg/v:SI 112 [ max_linksD.4175 ])
                        (const_int 0 [0]))
                    (leu:SI (reg/v:SI 112 [ max_linksD.4175 ])
                        (reg:SI 114 [ _15 ]))))
            (clobber (reg:CC 100 cc))
        ]) kernel-ice.c:49 262 {*and_scc_scc_nodom}
     (expr_list:REG_DEAD (reg:SI 114 [ _15 ])

which looks like alternative#0

kernel-ice.c.232r.reload:
(insn 47 118 48 6 (parallel [
            (set (reg/v:SI 1 r1 [orig:112 max_linksD.4175 ] [112])
                (and:SI (ne:SI (reg/v:SI 1 r1 [orig:112 max_linksD.4175 ]
[112])
                        (const_int 0 [0]))
                    (leu:SI (reg/v:SI 1 r1 [orig:112 max_linksD.4175 ] [112])
                        (reg:SI 2 r2 [orig:114 _15 ] [114]))))
            (clobber (reg:CC 100 cc))
        ]) kernel-ice.c:49 262 {*and_scc_scc_nodom}
     (nil))

which looks wrong, because
(define_insn_and_split "*and_scc_scc_nodom"
  [(set (match_operand:SI 0 "s_register_operand" "=&Ts,&Ts,&Ts")
        (and:SI (match_operator:SI 3 "arm_comparison_operator"
                 [(match_operand:SI 1 "s_register_operand" "r,r,0")
                  (match_operand:SI 2 "arm_add_operand" "rIL,0,rIL")])
                (match_operator:SI 6 "arm_comparison_operator"
                 [(match_operand:SI 4 "s_register_operand" "r,r,r")
                  (match_operand:SI 5 "arm_add_operand" "rIL,rIL,rIL")])))

reload uses alternative#2 which defines op[0] as early clobber "&Ts",
and op[1] identical to op[0], but now we have op[4] clobbered.

This seems to be another LRA bug.  Right?

My patch from yesterday makes no difference here, but what's funny is,
that the set register was originally r138 but now the dump says
"set (reg/v:SI 1 r1 [orig:112 ...".

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #6 from ktkachov at gcc dot gnu.org ---
Perhaps a bisection to the revision that started this could shed some light

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #7 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
(In reply to ktkachov from comment #6)
> Perhaps a bisection to the revision that started this could shed some light

absolutely, but my computer powers are too limited for that.  could you help?

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |trippels at gcc dot gnu.org

--- Comment #8 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #7)
> (In reply to ktkachov from comment #6)
> > Perhaps a bisection to the revision that started this could shed some light
> 
> absolutely, but my computer powers are too limited for that.  could you help?

You could use the compile farm machines, e.g. building a cross on gcc112, which
has 152 "cores".

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #9 from ktkachov at gcc dot gnu.org ---
(In reply to Bernd Edlinger from comment #7)
> (In reply to ktkachov from comment #6)
> > Perhaps a bisection to the revision that started this could shed some light
> 
> absolutely, but my computer powers are too limited for that.  could you help?

I'll give it a shot

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #10 from ktkachov at gcc dot gnu.org ---
The ICE started with:
Author: vmakarov <vmakarov@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Tue Sep 1 19:37:52 2015 +0000

    2015-09-01  Vladimir Makarov  <vmakarov@redhat.com>

        PR target/61578
        * lra-lives.c (process_bb_lives): Process move pseudos with the
        same value for copies and preferences
        * lra-constraints.c (match_reload): Create match reload pseudo
        with the same value from single dying input pseudo.



    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@227382
138bc75d-0d04-0410-961f-82ee72b054a4


So it seems like an LRA issue

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #11 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
I must admit, that I don't know what I am doing here,
... but this (completely untested) patch seems to fix the ICE:
(and at least my linux kernel compiles without ICE now)

--- lra-assigns.c.jj    2015-07-16 17:26:35.000000000 +0200
+++ lra-assigns.c       2015-10-01 14:40:06.262300720 +0200
@@ -576,7 +576,7 @@ find_hard_regno_for_1 (int regno, int *c
        /* Remember about multi-register pseudos.  For example, 2 hard
           register pseudos can start on the same hard register but can
           not start on HR and HR+1/HR-1.  */
-       for (hr = conflict_hr + 1;
+       for (hr = conflict_hr;
             hr < FIRST_PSEUDO_REGISTER && hr < conflict_hr + nregs;
             hr++)
          SET_HARD_REG_BIT (impossible_start_hard_regs, hr);



The problem starts when lra assigns r143 and r144 to r1
although both have obviously conflicting live ranges.

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[vmakarov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

Vladimir Makarov <vmakarov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vmakarov at gcc dot gnu.org

--- Comment #12 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #0)
> 
> fs/namei.c:3934:1: internal compiler error: in extract_constrain_insn, at
> recog.c:2200
> 0xa3db48 _fatal_insn(char const*, rtx_def const*, char const*, int, char
> const*)
> 	../../gcc-6-20150927/gcc/rtl-error.c:109
> 0xa3db6f _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
> 	../../gcc-6-20150927/gcc/rtl-error.c:120
> 0xa1028d extract_constrain_insn(rtx_insn*)
> 	../../gcc-6-20150927/gcc/recog.c:2200
> 0x9efc9d reload_cse_simplify_operands
> 	../../gcc-6-20150927/gcc/postreload.c:408
> 0x9f29b5 reload_cse_simplify
> 	../../gcc-6-20150927/gcc/postreload.c:194
> 0x9f29b5 reload_cse_regs_1
> 	../../gcc-6-20150927/gcc/postreload.c:233
> 0x9f2acb reload_cse_regs
> 	../../gcc-6-20150927/gcc/postreload.c:81
> 0x9f2acb execute
> 	../../gcc-6-20150927/gcc/postreload.c:2350
> Please submit a full bug report,
> with preprocessed source if appropriate.
> Please include the complete backtrace with any bug report.
> See <http://gcc.gnu.org/bugs.html> for instructions.

Thanks for reporting this.  I'll try to fix it this week.
>From gcc-bugs-return-498513-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Thu Oct 01 15:30:35 2015
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Subject: [Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM
Date: Thu, 01 Oct 2015 15:30:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #13 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #11)
> I must admit, that I don't know what I am doing here,
> ... but this (completely untested) patch seems to fix the ICE:
> (and at least my linux kernel compiles without ICE now)
> 

This is a wrong fix.  If the pseudos has the same value, they should not
conflict if they start with the same register.  This part of code concerns
exactly about the pseudos with the same value.

The root of the problem is in that the pseudos should not have the same value.

> --- lra-assigns.c.jj	2015-07-16 17:26:35.000000000 +0200
> +++ lra-assigns.c	2015-10-01 14:40:06.262300720 +0200
> @@ -576,7 +576,7 @@ find_hard_regno_for_1 (int regno, int *c
>  	/* Remember about multi-register pseudos.  For example, 2 hard
>  	   register pseudos can start on the same hard register but can
>  	   not start on HR and HR+1/HR-1.  */
> -	for (hr = conflict_hr + 1;
> +	for (hr = conflict_hr;
>  	     hr < FIRST_PSEUDO_REGISTER && hr < conflict_hr + nregs;
>  	     hr++)
>  	  SET_HARD_REG_BIT (impossible_start_hard_regs, hr);
> 
> 
> 
> The problem starts when lra assigns r143 and r144 to r1
> although both have obviously conflicting live ranges.
>From gcc-bugs-return-498514-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Thu Oct 01 15:36:45 2015
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Subject: [Bug c++/67796] Definition for custom std::swap found by ADL but not used
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idg796

--- Comment #2 from rkirchge at gmail dot com ---
Thank you for the quick reply.

Defining the swap overload in std does violate the standard, but it is the
shortest example that reproduces the behavior I am seeing.

In my code, I have defined a wrapper around std::tuple, and defined my own swap
and get function in the associated namespace. I am trying to get std::sort to
call my swap function to allow me to swap values stored in tuples of
references. In clang my code works. In gcc if I do not include my swap(...)
definition the compiler returns an error, but if I do include it it gives no
error but uses some default std::swap implementation which does not work with
tuples of references.

My overload of get(...) is called correctly in gcc, but swap(...) is not.

It will take me some time to cleanup my code, but I will post the example as
requested as soon as possible.

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[vmakarov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #14 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #5)

> 
> My patch from yesterday makes no difference here, but what's funny is,
> that the set register was originally r138 but now the dump says
> "set (reg/v:SI 1 r1 [orig:112 ...".

LRA creates a pseudo for matching reload operands and on the subsequent
sub-pass assign a hard register to it.  When we create the pseudo it can be
originated only from one pseudo p138 or p112 (matching pseudo operands). 
Therefore we have such result.

It could be fixed but I don't see the efforts needed to spend on this is worth
to fix this.  This discrepancy exists only between the insn and the
corresponding output reload.

[Bug target/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #15 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
(In reply to Vladimir Makarov from comment #14)
> (In reply to Bernd Edlinger from comment #5)
> 
> > 
> > My patch from yesterday makes no difference here, but what's funny is,
> > that the set register was originally r138 but now the dump says
> > "set (reg/v:SI 1 r1 [orig:112 ...".
> 
> LRA creates a pseudo for matching reload operands and on the subsequent
> sub-pass assign a hard register to it.  When we create the pseudo it can be
> originated only from one pseudo p138 or p112 (matching pseudo operands). 
> Therefore we have such result.
> 
> It could be fixed but I don't see the efforts needed to spend on this is
> worth to fix this.  This discrepancy exists only between the insn and the
> corresponding output reload.

I agree, that was a bit surprising deja-vu when I looked closely at the dump,
but this alias should not really hurt in deed.

[Bug rtl-optimization/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #16 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
(In reply to Vladimir Makarov from comment #13)
> (In reply to Bernd Edlinger from comment #11)
> > I must admit, that I don't know what I am doing here,
> > ... but this (completely untested) patch seems to fix the ICE:
> > (and at least my linux kernel compiles without ICE now)
> > 
> 
> This is a wrong fix.  If the pseudos has the same value, they should not
> conflict if they start with the same register.  This part of code concerns
> exactly about the pseudos with the same value.
> 
> The root of the problem is in that the pseudos should not have the same
> value.
> 

OK, now I see the problem.

How about this?

--- lra-constraints.c.jj        2015-09-25 23:06:08.000000000 +0200
+++ lra-constraints.c   2015-10-02 12:18:51.346267777 +0200
@@ -160,6 +160,8 @@ static machine_mode curr_operand_mode[MA
    (e.g. constant) and whose subreg is given operand of the current
    insn.  VOIDmode in all other cases.  */
 static machine_mode original_subreg_reg_mode[MAX_RECOG_OPERANDS];
+/* True if the operand is early clobber.  */
+static bool goal_alt_early_clobber[MAX_RECOG_OPERANDS];




@@ -949,8 +951,10 @@ match_reload (signed char out, signed ch
              in the output, e.g. as an address part in memory,
              becuase output reload will actually extend the pseudo
              liveness.  We don't care about eliminable hard regs here
-             as we are interesting only in pseudos.  */
-          && (out < 0 || regno_use_in (REGNO (in_rtx), out_rtx) == NULL_RTX)
+             as we are interesting only in pseudos.  This does not work
+             for early clobber outputs.  */
+          && (out < 0 || (regno_use_in (REGNO (in_rtx), out_rtx) == NULL_RTX
+                          && ! goal_alt_early_clobber[out]))
           ? lra_create_new_reg (inmode, in_rtx, goal_class, "")
           : lra_create_new_reg_with_unique_value (outmode, out_rtx,
                                                   goal_class, ""));
@@ -1693,6 +1697,7 @@ process_alt_operands (int only_alternati
   bool curr_alt_win[MAX_RECOG_OPERANDS];
   bool curr_alt_offmemok[MAX_RECOG_OPERANDS];
   int curr_alt_matches[MAX_RECOG_OPERANDS];
+  bool curr_alt_early_clobber[MAX_RECOG_OPERANDS];
   /* The number of elements in the following array.  */
   int curr_alt_dont_inherit_ops_num;
   /* Numbers of operands whose reload pseudos should not be inherited. */
@@ -1803,6 +1808,7 @@ process_alt_operands (int only_alternati
              curr_alt_match_win[nop] = false;
              curr_alt_offmemok[nop] = false;
              curr_alt_matches[nop] = -1;
+             curr_alt_early_clobber[nop] = false;
              continue;
            }

@@ -2483,6 +2489,7 @@ process_alt_operands (int only_alternati
          curr_alt_match_win[nop] = this_alternative_match_win;
          curr_alt_offmemok[nop] = this_alternative_offmemok;
          curr_alt_matches[nop] = this_alternative_matches;
+         curr_alt_early_clobber[nop] = early_clobber_p;

          if (this_alternative_matches >= 0
              && !did_match && !this_alternative_win)
@@ -2642,6 +2649,7 @@ process_alt_operands (int only_alternati
              goal_alt_win[nop] = curr_alt_win[nop];
              goal_alt_match_win[nop] = curr_alt_match_win[nop];
              goal_alt_matches[nop] = curr_alt_matches[nop];
+             goal_alt_early_clobber[nop] = curr_alt_early_clobber[nop];
              goal_alt[nop] = curr_alt[nop];
              goal_alt_offmemok[nop] = curr_alt_offmemok[nop];
            }
@@ -3366,6 +3374,7 @@ curr_insn_transform (bool check_only_p)
     {
       goal_alt_matched[i][0] = -1;
       goal_alt_matches[i] = -1;
+      goal_alt_early_clobber[i] = false;
     }

   commutative = curr_static_id->commutative;

[Bug rtl-optimization/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[vmakarov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #17 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
(In reply to Bernd Edlinger from comment #16)
> (In reply to Vladimir Makarov from comment #13)
> > (In reply to Bernd Edlinger from comment #11)
> > > I must admit, that I don't know what I am doing here,
> > > ... but this (completely untested) patch seems to fix the ICE:
> > > (and at least my linux kernel compiles without ICE now)
> > > 
> > 
> > This is a wrong fix.  If the pseudos has the same value, they should not
> > conflict if they start with the same register.  This part of code concerns
> > exactly about the pseudos with the same value.
> > 
> > The root of the problem is in that the pseudos should not have the same
> > value.
> > 
> 
> OK, now I see the problem.
> 
> How about this?
> 
The patch can be a solution.  It is a right direction.  Thanks for working on
this.  I have a patch already too.  I am just testing it.  I'll commit it in a
few hours.

[Bug rtl-optimization/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[vmakarov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #18 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
Author: vmakarov
Date: Fri Oct  2 15:04:59 2015
New Revision: 228396

URL: https://gcc.gnu.org/viewcvs?rev=228396&root=gcc&view=rev
Log:
2015-10-02  Vladimir Makarov  <vmakarov@redhat.com>

        PR rtl-optimization/67756
        * lra-constraints.c (match_reload): Add a new parameter.  Use it
        for creating a pseudo with the same value.
        (curr_insn_transform): Pass a new argument to match_reload.

2015-10-02  Vladimir Makarov  <vmakarov@redhat.com>

        PR rtl-optimization/67756
        * gcc.target/arm/pr67756.c: New.


Added:
    trunk/gcc/testsuite/gcc.target/arm/pr67756.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/lra-constraints.c
    trunk/gcc/testsuite/ChangeLog

[Bug rtl-optimization/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

--- Comment #19 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
ok, but now we have because of the warnings:

FAIL: gcc.target/arm/pr67756.c (test for excess errors)

I think something like this could fix it:

Index: pr67756.c
===================================================================
--- pr67756.c   (revision 228404)
+++ pr67756.c   (working copy)
@@ -2,6 +2,8 @@
 /* { dg-require-effective-target arm_hard_vfp_ok } */
 /* { dg-options "-O2 -mapcs -march=armv7-a -mfloat-abi=hard -mfpu=vfpv3-d16" }
*/

+int inode_permission (), try_break_deleg ();
+int mutex_lock (), mutex_unlock ();
 struct mutex
 {
 };

[Bug rtl-optimization/67756] [6 Regression] ICE compiling Linux Kernel fs/namei.c on ARM

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67756

Bernd Edlinger <bernd.edlinger at hotmail dot de> changed:

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

--- Comment #21 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
(In reply to Vladimir Makarov from comment #20)
> Thanks for checking.  Could you commit it.  Thanks.

OK, done, r228445.