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 diff --git a/arch/m68k/fpsp040/sasin.S b/arch/m68k/fpsp040/sasin.Snew file mode 100644index 00000000000..5647a604390--- /dev/null+++ b/arch/m68k/fpsp040/sasin.S@@ -0,0 +1,104 @@+|+| sasin.sa 3.3 12/19/90+|+| Description: The entry point sAsin computes the inverse sine of+| an input argument; sAsind does the same except for denormalized+| input.+|+| Input: Double-extended number X in location pointed to+| by address register a0.+|+| Output: The value arcsin(X) returned in floating-point register Fp0.+|+| Accuracy and Monotonicity: The returned result is within 3 ulps in+| 64 significant bit, i.e. within 0.5001 ulp to 53 bits if the+| result is subsequently rounded to double precision. The+| result is provably monotonic in double precision.+|+| Speed: The program sASIN takes approximately 310 cycles.+|+| Algorithm:+|+| ASIN+| 1. If |X| >= 1, go to 3.+|+| 2. (|X| < 1) Calculate asin(X) by+| z := sqrt( [1-X][1+X] )+| asin(X) = atan( x / z ).+| Exit.+|+| 3. If |X| > 1, go to 5.+|+| 4. (|X| = 1) sgn := sign(X), return asin(X) := sgn * Pi/2. Exit.+|+| 5. (|X| > 1) Generate an invalid operation by 0 * infinity.+| Exit.+|++| Copyright (C) Motorola, Inc. 1990+| All Rights Reserved+|+| THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA+| The copyright notice above does not evidence any+| actual or intended publication of such source code.++|SASIN idnt 2,1 | Motorola 040 Floating Point Software Package++ |section 8++PIBY2: .long 0x3FFF0000,0xC90FDAA2,0x2168C235,0x00000000++ |xref t_operr+ |xref t_frcinx+ |xref t_extdnrm+ |xref satan++ .global sasind+sasind:+|--ASIN(X) = X FOR DENORMALIZED X++ bra t_extdnrm++ .global sasin+sasin:+ fmovex (%a0),%fp0 | ...LOAD INPUT++ movel (%a0),%d0+ movew 4(%a0),%d0+ andil #0x7FFFFFFF,%d0+ cmpil #0x3FFF8000,%d0+ bges asinbig++|--THIS IS THE USUAL CASE, |X| < 1+|--ASIN(X) = ATAN( X / SQRT( (1-X)(1+X) ) )++ fmoves #0x3F800000,%fp1+ fsubx %fp0,%fp1 | ...1-X+ fmovemx %fp2-%fp2,-(%a7)+ fmoves #0x3F800000,%fp2+ faddx %fp0,%fp2 | ...1+X+ fmulx %fp2,%fp1 | ...(1+X)(1-X)+ fmovemx (%a7)+,%fp2-%fp2+ fsqrtx %fp1 | ...SQRT([1-X][1+X])+ fdivx %fp1,%fp0 | ...X/SQRT([1-X][1+X])+ fmovemx %fp0-%fp0,(%a0)+ bsr satan+ bra t_frcinx++asinbig:+ fabsx %fp0 | ...|X|+ fcmps #0x3F800000,%fp0+ fbgt t_operr |cause an operr exception++|--|X| = 1, ASIN(X) = +- PI/2.++ fmovex PIBY2,%fp0+ movel (%a0),%d0+ andil #0x80000000,%d0 | ...SIGN BIT OF X+ oril #0x3F800000,%d0 | ...+-1 IN SGL FORMAT+ movel %d0,-(%sp) | ...push SIGN(X) IN SGL-FMT+ fmovel %d1,%FPCR+ fmuls (%sp)+,%fp0+ bra t_frcinx++ |end