4.3BSD - /usr/src/usr.lib/libm/VAX/sincos.s

   1: #
   2: # Copyright (c) 1985 Regents of the University of California.
   3: #
   4: # Use and reproduction of this software are granted  in  accordance  with
   5: # the terms and conditions specified in  the  Berkeley  Software  License
   6: # Agreement (in particular, this entails acknowledgement of the programs'
   7: # source, and inclusion of this notice) with the additional understanding
   8: # that  all  recipients  should regard themselves as participants  in  an
   9: # ongoing  research  project and hence should  feel  obligated  to report
  10: # their  experiences (good or bad) with these elementary function  codes,
  11: # using "sendbug 4bsd-bugs@BERKELEY", to the authors.
  12: #
  13: 
  14: # @(#)sincos.s	1.1 (Berkeley) 8/21/85
  15: 
  16: #  This is the implementation of Peter Tang's double precision
  17: #  sine and cosine for the VAX using Bob Corbett's argument reduction.
  18: #
  19: #  Notes:
  20: #       under 1,024,000 random arguments testing on [0,2*pi]
  21: #       sin() observed maximum error = 0.814 ulps
  22: #       cos() observed maximum error = 0.792 ulps
  23: #
  24: # double sin(arg)
  25: # double arg;
  26: # method: true range reduction to [-pi/4,pi/4], P. Tang  &  B. Corbett
  27: # S. McDonald, April 4,  1985
  28: #
  29:         .globl  _sin
  30:         .text
  31:         .align  1
  32: 
  33: _sin:   .word   0xffc           # save r2-r11
  34:         movq    4(ap),r0
  35:         bicw3   $0x807f,r0,r2
  36:         beql    1f              # if x is zero or reserved operand then return x
  37: #
  38: # Save the PSL's IV & FU bits on the stack.
  39: #
  40:         movpsl  r2
  41:         bicw3   $0xff9f,r2,-(sp)
  42: #
  43: # Clear the IV & FU bits.
  44: #
  45:         bicpsw  $0x0060
  46: #
  47: #  Entered by  sine    ; save  0  in  r4 .
  48: #
  49:         jsb     libm$argred
  50:         movl    $0,r4
  51:         jsb     libm$sincos
  52:         bispsw  (sp)+
  53: 1:      ret
  54: 
  55: #
  56: # double cos(arg)
  57: # double arg;
  58: # method: true range reduction to [-pi/4,pi/4], P. Tang  &  B. Corbett
  59: # S. McDonald, April 4,  1985
  60: #
  61:         .globl  _cos
  62:         .text
  63:         .align  1
  64: 
  65: _cos:   .word   0xffc           # save r2-r11
  66:         movq    4(ap),r0
  67:         bicw3   $0x7f,r0,r2
  68:         cmpw    $0x8000,r2
  69:         beql    1f              # if x is reserved operand then return x
  70: #
  71: # Save the PSL's IV & FU bits on the stack.
  72: #
  73:         movpsl  r2
  74:         bicw3   $0xff9f,r2,-(sp)
  75: #
  76: # Clear the IV & FU bits.
  77: #
  78:         bicpsw  $0x0060
  79: #
  80: #  Entered by  cosine  ; save  1  in  r4 .
  81: #
  82:         jsb     libm$argred
  83:         movl    $1,r4
  84:         jsb     libm$sincos
  85:         bispsw  (sp)+
  86: 1:      ret

Defined functions