35 lines
578 B
ArmAsm
35 lines
578 B
ArmAsm
/
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/ .data
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/ .asciz "@(#)exp.s 1.1 92/07/30 SMI"
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/ .even
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/ .text
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/
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/ Copyright (c) 1987 by Sun Microsystems, Inc.
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.text
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.globl exp
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exp:
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fldl 4(%esp) / push arg
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fldl2e / push log2(e)
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fmulp %st,%st(1) / z = arg*log2(e)
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fld %st(0) / duplicate stack top
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frndint / [z],z
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fxch / z,[z]
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fucom
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fnstsw %ax
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sahf
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je L1
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fsub %st(1),%st / z-[z],[z]
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f2xm1 / 2**(z-[z])-1, [z]
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fld1 / 1,2**(z-[z])-1, [z]
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faddp %st,%st(1) / 2**(z-[z]),[z]
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fscale / 2**z = 2**(arg*log2e) = exp(arg)
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fstp %st(1)
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ret
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L1:
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fstp %st(0)
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fld1
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fscale
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fstp %st(1)
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ret
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