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Diffstat (limited to 'c/src/lib/libcpu/m68k/m68040/fpsp/sacos.S')
| -rw-r--r-- | c/src/lib/libcpu/m68k/m68040/fpsp/sacos.S | 117 |
1 files changed, 0 insertions, 117 deletions
diff --git a/c/src/lib/libcpu/m68k/m68040/fpsp/sacos.S b/c/src/lib/libcpu/m68k/m68040/fpsp/sacos.S deleted file mode 100644 index fa9409db52..0000000000 --- a/c/src/lib/libcpu/m68k/m68040/fpsp/sacos.S +++ /dev/null @@ -1,117 +0,0 @@ -#include "fpsp-namespace.h" -// -// -// sacos.sa 3.3 12/19/90 -// -// Description: The entry point sAcos computes the inverse cosine of -// an input argument; sAcosd does the same except for denormalized -// input. -// -// Input: Double-extended number X in location pointed to -// by address register a0. -// -// Output: The value arccos(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 sCOS takes approximately 310 cycles. -// -// Algorithm: -// -// ACOS -// 1. If |X| >= 1, go to 3. -// -// 2. (|X| < 1) Calculate acos(X) by -// z := (1-X) / (1+X) -// acos(X) = 2 * atan( sqrt(z) ). -// Exit. -// -// 3. If |X| > 1, go to 5. -// -// 4. (|X| = 1) If X > 0, return 0. Otherwise, return Pi. 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 -// - -// Copyright (C) Motorola, Inc. 1990 -// All Rights Reserved -// -// THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA -// The copyright notice above does not evidence any -// actual or intended publication of such source code. - -//SACOS idnt 2,1 | Motorola 040 Floating Point Software Package - - |section 8 - -PI: .long 0x40000000,0xC90FDAA2,0x2168C235,0x00000000 -PIBY2: .long 0x3FFF0000,0xC90FDAA2,0x2168C235,0x00000000 - - |xref t_operr - |xref t_frcinx - |xref satan - - .global sacosd -sacosd: -//--ACOS(X) = PI/2 FOR DENORMALIZED X - fmovel %d1,%fpcr // ...load user's rounding mode/precision - fmovex PIBY2,%fp0 - bra t_frcinx - - .global sacos -sacos: - fmovex (%a0),%fp0 // ...LOAD INPUT - - movel (%a0),%d0 // ...pack exponent with upper 16 fraction - movew 4(%a0),%d0 - andil #0x7FFFFFFF,%d0 - cmpil #0x3FFF8000,%d0 - bges ACOSBIG - -//--THIS IS THE USUAL CASE, |X| < 1 -//--ACOS(X) = 2 * ATAN( SQRT( (1-X)/(1+X) ) ) - - fmoves #0x3F800000,%fp1 - faddx %fp0,%fp1 // ...1+X - fnegx %fp0 // ... -X - fadds #0x3F800000,%fp0 // ...1-X - fdivx %fp1,%fp0 // ...(1-X)/(1+X) - fsqrtx %fp0 // ...SQRT((1-X)/(1+X)) - fmovemx %fp0-%fp0,(%a0) // ...overwrite input - movel %d1,-(%sp) //save original users fpcr - clrl %d1 - bsr satan // ...ATAN(SQRT([1-X]/[1+X])) - fmovel (%sp)+,%fpcr //restore users exceptions - faddx %fp0,%fp0 // ...2 * ATAN( STUFF ) - bra t_frcinx - -ACOSBIG: - fabsx %fp0 - fcmps #0x3F800000,%fp0 - fbgt t_operr //cause an operr exception - -//--|X| = 1, ACOS(X) = 0 OR PI - movel (%a0),%d0 // ...pack exponent with upper 16 fraction - movew 4(%a0),%d0 - cmpl #0,%d0 //D0 has original exponent+fraction - bgts ACOSP1 - -//--X = -1 -//Returns PI and inexact exception - fmovex PI,%fp0 - fmovel %d1,%FPCR - fadds #0x00800000,%fp0 //cause an inexact exception to be put -// ;into the 040 - will not trap until next -// ;fp inst. - bra t_frcinx - -ACOSP1: - fmovel %d1,%FPCR - fmoves #0x00000000,%fp0 - rts //Facos ; of +1 is exact - - |end |