• Julia Lawall's avatar
    [S390] s390: Remove redundant test · acfa922c
    Julia Lawall authored
    The loop above the modified code only terminates when rc is a valid pointer.
    
    A simplified version of the semantic patch that makes this change is as
    follows: (http://www.emn.fr/x-info/coccinelle/)
    
    // <smpl>
    @r exists@
    local idexpression x;
    expression E;
    position p1,p2;
    @@
    
    if (x@p1 == NULL || ...) { ... when forall
       return ...; }
    ... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
    (
    x@p2 == NULL
    |
    x@p2 != NULL
    )
    
    // another path to the test that is not through p1?
    @s exists@
    local idexpression r.x;
    position r.p1,r.p2;
    @@
    
    ... when != x@p1
    (
    x@p2 == NULL
    |
    x@p2 != NULL
    )
    
    @fix depends on !s@
    position r.p1,r.p2;
    expression x,E;
    statement S1,S2;
    @@
    
    (
    - if ((x@p2 != NULL) || ...)
      S1
    |
    - if ((x@p2 == NULL) && ...) S1
    |
    - BUG_ON(x@p2 == NULL);
    )
    // </smpl>
    Signed-off-by: default avatarJulia Lawall <julia@diku.dk>
    Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    acfa922c
qeth_core_main.c 123 KB