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From: "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/108552] Linux i386 kernel 5.14 memory corruption for
 pre_compound_page() when gcov is enabled
Date: Fri, 27 Jan 2023 12:23:44 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108552

--- Comment #16 from Uro=C5=A1 Bizjak <ubizjak at gmail dot com> ---
        addl    $1, __gcov0.prep_compound_page+48
        adcl    $0, __gcov0.prep_compound_page+52
        cmpl    $1, %ebx
        jle     .L1470
        leal    1(%edi), %eax
        movl    __gcov0.prep_compound_page+60, %edx  <- load %eax/%edx from=
 $
        movl    %eax, -24(%ebp)
        movl    __gcov0.prep_compound_page+56, %eax
        leal    40(%edi), %ecx
        movl    %edi, -32(%ebp)
        addl    $1, %eax         <- add $1 to %eax/%edx
        movl    %eax, -20(%ebp)  <- save to stack frame loc 20
        adcl    $0, %edx
        movl    __gcov0.prep_compound_page+56, %eax  <- load again %eax/%edx
from $
        movl    %edx, -16(%ebp)
        movl    __gcov0.prep_compound_page+60, %edx
        subl    $2, %ebx         <- subtract $2 to %ebx, zext to %ebx/%esi
        xorl    %esi, %esi
        addl    $2, %eax         <- add $2 to %eax/%edx
        adcl    $0, %edx
        addl    %eax, %ebx       <- move %eax/%edx to %ebx/%esi
        movl    -20(%ebp), %eax  <- load %eax/%edx from stack frame loc 20
        adcl    %edx, %esi
        movl    -16(%ebp), %edx
        movl    %esi, %edi       <- move %ebx/%esi to %esi/%edi
        movl    %ebx, %esi=