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    SubjectRe: Runaway cron task on 2.5.63/4 bk?
    Linus Torvalds <torvalds@transmeta.com> wrote:
    >
    >
    > On Tue, 11 Mar 2003, Andrew Morton wrote:
    > >
    > > 2.95.3 and 3.2.1 seem to do it right?
    >
    > Try the "64x32->64" version. gcc didn't use to get that one right, but
    > maybe it does now.
    >


    long a;
    long long b;
    long long c;

    void foo(void)
    {
    c = a * b;
    }

    It seems to get that wrong. At least, there are three multiplies in there.
    3.2.1 is similar.


    .file "t.c"
    .version "01.01"
    gcc2_compiled.:
    .text
    .align 4
    .globl foo
    .type foo,@function
    foo:
    pushl %ebp
    movl %esp,%ebp
    subl $16,%esp
    pushl %esi
    pushl %ebx
    movl a,%eax
    movl %eax,%ebx
    movl %eax,%esi
    sarl $31,%esi
    movl %ebx,%eax
    mull b
    movl %eax,-8(%ebp)
    movl %edx,-4(%ebp)
    movl %ebx,%eax
    imull b+4,%eax
    addl %eax,%edx
    movl %edx,-4(%ebp)
    movl b,%eax
    imull %esi,%eax
    addl %eax,-4(%ebp)
    movl -8(%ebp),%eax
    movl -4(%ebp),%edx
    movl %eax,c
    movl %edx,c+4
    popl %ebx
    popl %esi
    movl %ebp,%esp
    popl %ebp
    ret
    .Lfe1:
    .size foo,.Lfe1-foo
    .comm a,4,4
    .comm b,8,4
    .comm c,8,4
    .ident "GCC: (GNU) 2.95.3 20010315 (release)"

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