Reverse Engineering challenge #84.

What does this code do?

Optimizing GCC 4.8.4 (x64, SSE enabled):


f:
.LFB0:
	mulsd	xmm0, QWORD PTR .LC0[rip]
	divsd	xmm0, QWORD PTR .LC1[rip]
	ret
.LC0:
	.long	1413754136
	.long	1074340347
.LC1:
	.long	0
	.long	1080459264

Optimizing GCC 4.8.4 (FPU code (-mfpmath=387 key)):


f:
	movsd	QWORD PTR [rsp-24], xmm0
	fldpi
	fld	QWORD PTR [rsp-24]
	fmulp	st(1), st
	fdiv	DWORD PTR .LC1[rip]
	fstp	QWORD PTR [rsp-16]
	movsd	xmm0, QWORD PTR [rsp-16]
	ret
.LC1:
	.long	1127481344

Optimizing GCC 4.9.3 for ARM64:


f:
        ldr     d1, .LC0
        fmul    d0, d0, d1
        ldr     d1, .LC1
        fdiv    d0, d0, d1
        ret
.LC0:
        .word   1413754136
        .word   1074340347
.LC1:
        .word   0
        .word   1080459264

(ARM) Optimizing Keil 5.05 (ARM mode):


f PROC
        PUSH     {r4,lr}
        LDR      r2,|L0.32|
        LDR      r3,|L0.36|
        BL       __aeabi_dmul
        POP      {r4,lr}
        LDR      r3,|L0.40|
        MOV      r2,#0
        B        __aeabi_ddiv
        ENDP

|L0.32|
        DCD      0x54442d18
|L0.36|
        DCD      0x400921fb
|L0.40|
        DCD      0x40668000

        DCD      0x00000000

(ARM) Optimizing Keil 5.05 (Thumb mode):

... the code is almost the same as for ARM mode.

Optimizing GCC 4.4.5 for MIPS:


f:
        lui     $2,%hi($LC0)
        lwc1    $f0,%lo($LC0+4)($2)
        nop
        lwc1    $f1,%lo($LC0)($2)
        lui     $2,%hi($LC1)
        mul.d   $f0,$f12,$f0
        lwc1    $f2,%lo($LC1+4)($2)
        nop
        lwc1    $f3,%lo($LC1)($2)
        j       $31
        div.d   $f0,$f0,$f2
$LC0:
        .word   1074340347
        .word   1413754136
$LC1:
        .word   1080459264
        .word   0

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