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* [Bug tree-optimization/67949] New: Regression in GCC-6.0.0's optimizer
@ 2015-10-13  9:54 ishiura-compiler at ml dot kwansei.ac.jp
  2015-10-13 10:48 ` [Bug tree-optimization/67949] " mpolacek at gcc dot gnu.org
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: ishiura-compiler at ml dot kwansei.ac.jp @ 2015-10-13  9:54 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67949

            Bug ID: 67949
           Summary: Regression in GCC-6.0.0's optimizer
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ishiura-compiler at ml dot kwansei.ac.jp
  Target Milestone: ---

We compiled a program (A.c) by GCC-5.1.0 and GCC-6.0.0 with -O3 option.
GCC-5.1.0 performed better optimization than GCC-6.0.0.

(A.c)
#include <stdio.h>
int x110 = 0;
int main (void)
{
        volatile int x129 = 1;
        int t0 = 1;

        t0 = (x129==1)<=(2U^(-(1-x110<<2)));

        if (t0 == 1) { } 
        else { __builtin_abort(); }

    return 0;
}

+-----------------------------------------+-----------------------------------------+
|    gcc-5.1.0.s (gcc-5.1.0 A.c -O3 -S)   |   gcc-6.0.0.s (gcc-6.0.0 A.c -O3
-S)    |
+-----------------------------------------+-----------------------------------------+
|        .globl  main                     |        .globl  main                
    |
|        .type   main, @function          |        .type   main, @function     
    |
|main:                                    |main:                               
    |
|.LFB23:                                  |.LFB11:                             
    |
|        .cfi_startproc                   |        .cfi_startproc              
    |
|        movl    $1, -4(%rsp)             |        subq    $24, %rsp           
    |
|        movl    -4(%rsp), %eax           |        .cfi_def_cfa_offset 32      
    |
|                                         |        xorl    %edx, %edx          
    |
|                                         |        movl    $1, 12(%rsp)        
    |
|                                         |        movl    12(%rsp), %eax      
    |
|                                         |        cmpl    $1, %eax            
    |
|                                         |        movl    $1, %eax            
    |
|                                         |        sete    %dl                 
    |
|                                         |        subl    x110(%rip), %eax    
    |
|                                         |        sall    $2, %eax            
    |
|                                         |        negl    %eax                
    |
|                                         |        xorl    $2, %eax            
    |
|                                         |        cmpl    %eax, %edx          
    |
|                                         |        ja      .L5                 
    |
|        xorl    %eax, %eax               |        xorl    %eax, %eax          
    |
|                                         |        addq    $24, %rsp           
    |
|                                         |        .cfi_remember_state         
    |
|                                         |        .cfi_def_cfa_offset 8       
    |
|        ret                              |        ret                         
    |
|                                         |.L5:                                
    |
|                                         |        .cfi_restore_state          
    |
|                                         |        call    abort               
    |
|        .cfi_endproc                     |        .cfi_endproc                
    |
|.LFE23:                                  |.LFE11:                             
    |
|        .size   main, .-main             |        .size   main, .-main        
    |
|        .section        .text.unlikely   |        .section       
.text.unlikely   |
|.LCOLDE0:                                |.LCOLDE0:                           
    |
|        .size   x110, 4                  |        .size   x110, 4             
    |
|x110:                                    |x110:                               
    |
|        .zero   4                        |        .zero   4                   
    |
+-----------------------------------------+-----------------------------------------+

Using built-in specs.
COLLECT_GCC=gcc-5
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu
5.1.0-0ubuntu11~14.04.1' --with-bugurl=file:///usr/share/doc/gcc-5/README.Bugs
--enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-5 --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=c++98 --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib
--disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo
--with-java-home=/usr/lib/jvm/java-1.5.0-gcj-5-amd64/jre --enable-java-home
--with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-5-amd64
--with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-5-amd64
--with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar
--enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686
--with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib
--with-tune=generic --enable-checking=release --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 5.1.0 (Ubuntu 5.1.0-0ubuntu11~14.04.1) 

Using built-in specs.
COLLECT_GCC=gcc-6.0.0
COLLECT_LTO_WRAPPER=/home/iwatsuji/opt/gcc-6.0.0/libexec/gcc/x86_64-unknown-linux-gnu/6.0.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-build/gcc-master/configure
--prefix=/home/iwatsuji/opt/gcc-6.0.0 --enable-language=c --disable-nls
--disable-multilib
Thread model: posix
gcc version 6.0.0 20150416 (experimental) (GCC)


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/67949] Regression in GCC-6.0.0's optimizer
  2015-10-13  9:54 [Bug tree-optimization/67949] New: Regression in GCC-6.0.0's optimizer ishiura-compiler at ml dot kwansei.ac.jp
@ 2015-10-13 10:48 ` mpolacek at gcc dot gnu.org
  2015-10-13 13:01 ` rguenth at gcc dot gnu.org
  2015-10-15  1:42 ` ishiura-compiler at ml dot kwansei.ac.jp
  2 siblings, 0 replies; 4+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2015-10-13 10:48 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67949

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

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

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I can't reproduce, with the current trunk I see

    .p2align 4,,15
    .globl  main
    .type   main, @function
main:
.LFB11:
    .cfi_startproc
    movl    $1, -4(%rsp)
    movl    -4(%rsp), %eax
    xorl    %eax, %eax
    ret
    .cfi_endproc
.LFE11:
    .size   main, .-main
    .globl  x110
    .bss
    .align 4
    .type   x110, @object
    .size   x110, 4
x110:
    .zero   4


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/67949] Regression in GCC-6.0.0's optimizer
  2015-10-13  9:54 [Bug tree-optimization/67949] New: Regression in GCC-6.0.0's optimizer ishiura-compiler at ml dot kwansei.ac.jp
  2015-10-13 10:48 ` [Bug tree-optimization/67949] " mpolacek at gcc dot gnu.org
@ 2015-10-13 13:01 ` rguenth at gcc dot gnu.org
  2015-10-15  1:42 ` ishiura-compiler at ml dot kwansei.ac.jp
  2 siblings, 0 replies; 4+ messages in thread
From: rguenth at gcc dot gnu.org @ 2015-10-13 13:01 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67949

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

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

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Seems to be fixed if it was ever broken.


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/67949] Regression in GCC-6.0.0's optimizer
  2015-10-13  9:54 [Bug tree-optimization/67949] New: Regression in GCC-6.0.0's optimizer ishiura-compiler at ml dot kwansei.ac.jp
  2015-10-13 10:48 ` [Bug tree-optimization/67949] " mpolacek at gcc dot gnu.org
  2015-10-13 13:01 ` rguenth at gcc dot gnu.org
@ 2015-10-15  1:42 ` ishiura-compiler at ml dot kwansei.ac.jp
  2 siblings, 0 replies; 4+ messages in thread
From: ishiura-compiler at ml dot kwansei.ac.jp @ 2015-10-15  1:42 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67949

--- Comment #3 from Ishiura Lab Compiler Team <ishiura-compiler at ml dot kwansei.ac.jp> ---
We are very sorry that somehow we failed to do final check with the latest
trunk before submitting the report.


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2015-10-15  1:42 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2015-10-13  9:54 [Bug tree-optimization/67949] New: Regression in GCC-6.0.0's optimizer ishiura-compiler at ml dot kwansei.ac.jp
2015-10-13 10:48 ` [Bug tree-optimization/67949] " mpolacek at gcc dot gnu.org
2015-10-13 13:01 ` rguenth at gcc dot gnu.org
2015-10-15  1:42 ` ishiura-compiler at ml dot kwansei.ac.jp

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