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[Bug target/17619] Non-optimal code for -mfpmath=387,sse


------- Additional Comments From uros at gcc dot gnu dot org  2004-12-01 14:07 -------
With "GCC: (GNU) 4.0.0 20041201 (experimental)", following code is produced
(without -ffast-math):

_Z6foobarv:
.LFB2:
        pushl   %ebp
.LCFI0:
        movl %esp, %ebp
.LCFI1:
        subl $4, %esp
.LCFI2:
        flds b+12
        fmuls   a+12
        movss   b, %xmm1
        mulss   a, %xmm1
        addss   .LC0, %xmm1
        movss   b+4, %xmm0
        mulss   a+4, %xmm0
        addss   %xmm0, %xmm1
        movss   b+8, %xmm0
        mulss   a+8, %xmm0
        addss   %xmm0, %xmm1
        movss   %xmm1, -4(%ebp)
        flds -4(%ebp)
        faddp   %st, %st(1)
        leave
        ret

Please note, that we should return the result in fp reg, so final flds is needed
in any case. I think, this code is optimal.

Should we close this bug?

Uros.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17619


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