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[Bug middle-end/24969] tmpdir-gcc.dg-struct-layout-1/t026 fails execution



------- Comment #5 from rguenth at gcc dot gnu dot org  2005-11-21 14:06 -------
Disassembly with the first two checks removed (only the third aborts):

foo:
.LFB2:
        subq    $24, %rsp       #,
.LCFI0:
        movl    x+8(%rip), %eax #, tmp62
        movl    16(%rsp), %edx  #, tmp60
        movq    %rdi, 8(%rsp)   # a, a
        andl    $2147483647, %eax       #, tmp62
        andl    $2147483647, %edx       #, tmp60
        cmpl    %eax, %edx      # tmp62, tmp60
        jne     .L6     #,
        addq    $24, %rsp       #,
        ret
.L6:
        call    abort   #

main:
.LFB3:
        subq    $8, %rsp        #,
.LCFI1:
        movl    x+8(%rip), %eax #, tmp62
        movw    $30216, x(%rip) #, x.a
        movb    $1, x+4(%rip)   #, x.b.c.d
        movq    x(%rip), %rdi   # x, x
        andl    $-2147483648, %eax      #, tmp62
        orl     $32766, %eax    #, tmp62
        movl    %eax, x+8(%rip) # tmp62,
        call    foo     #
        xorl    %eax, %eax      # <result>
        addq    $8, %rsp        #,
        ret


it looks like we are confused on where we passed the structure by value.
It's in %rdi and %eax, while we think it got passed on stack(!?) in foo.

Someone with more x86_64 ABI knowledge has to look into this.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hubicka at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24969


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