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    SubjectRe: Runaway cron task on 2.5.63/4 bk?
    Linus Torvalds <> wrote:
    > On Tue, 11 Mar 2003, Andrew Morton wrote:
    > >
    > > gcc will generate 64bit * 64bit multiplies without resorting to
    > > any library code
    > However, gcc is unable to do-the-right-thing and generate 32x32->64
    > multiplies, or 32x64->64 multiplies, even though those are both a _lot_
    > faster than the full 64x64->64 case.

    2.95.3 and 3.2.1 seem to do it right?

    long a;
    long b;
    long long c;

    void foo(void)
    c = a * b;

    .file "t.c"
    .version "01.01"
    .align 4
    .globl foo
    .type foo,@function
    pushl %ebp
    movl %esp,%ebp
    movl a,%eax
    imull b,%eax
    movl %eax,c
    movl %edx,c+4
    movl %ebp,%esp
    popl %ebp
    .size foo,.Lfe1-foo
    .comm a,4,4
    .comm b,4,4
    .comm c,8,4
    .ident "GCC: (GNU) 2.95.3 20010315 (release)"

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      Last update: 2005-03-22 13:33    [W:0.022 / U:78.540 seconds]
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