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    SubjectRe: [RFC: 2.6 patch] add -fno-tree-scev-cprop to KBUILD_CFLAGS
    Adrian Bunk wrote:
    > The gcc from svn that will become gcc 4.3 generates libgcc calls in
    > cases like the following (on 32bit architectures):
    >
    > <-- snip -->
    >
    > static inline void timespec_add_ns(struct timespec *a, u64 ns)
    > {
    > ...
    > while(ns >= NSEC_PER_SEC) {
    > ns -= NSEC_PER_SEC;
    > a->tv_sec++;
    > }
    > ...
    >
    > <-- snip -->
    >
    > It can make sense to emit assembler code doing division for such C code -
    > that doesn't seem to be something that would generally be wrong.

    It can be a pretty huge performance regression, so gcc ought to be fixed.


    Bernd
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