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authorUlrich Drepper <drepper@redhat.com>2001-02-19 09:09:18 +0000
committerUlrich Drepper <drepper@redhat.com>2001-02-19 09:09:18 +0000
commit8da2915d5dcfa51cb5f9e55f7716b49858c1d59d (patch)
treeaa219472cc41fcb82789b12723628cb6a33cc774 /sysdeps/ia64/fpu/s_atanl.S
parente208f556cad11f729533385e46e4191fcc49aa0a (diff)
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Update.
2001-02-19  Ulrich Drepper  <drepper@redhat.com>

	* libio/iogetline.c: Move return until after last statement.

	* localedata/show-ucs-data.c: Don't show < > for better readability.

	* sysdeps/ia64/fpu/Dist: New file.
	* sysdeps/ia64/fpu/Makefile: New file.
	* sysdeps/ia64/fpu/Versions: New file.
	* sysdeps/ia64/fpu/e_acos.S: New file.
	* sysdeps/ia64/fpu/e_acosf.S: New file.
	* sysdeps/ia64/fpu/e_acosl.S: New file.
	* sysdeps/ia64/fpu/e_asin.S: New file.
	* sysdeps/ia64/fpu/e_asinf.S: New file.
	* sysdeps/ia64/fpu/e_asinl.S: New file.
	* sysdeps/ia64/fpu/e_atan2.S: New file.
	* sysdeps/ia64/fpu/e_atan2f.S: New file.
	* sysdeps/ia64/fpu/e_atan2l.c: New file.
	* sysdeps/ia64/fpu/e_cosh.S: New file.
	* sysdeps/ia64/fpu/e_coshf.S: New file.
	* sysdeps/ia64/fpu/e_coshl.S: New file.
	* sysdeps/ia64/fpu/e_exp.S: New file.
	* sysdeps/ia64/fpu/e_expf.S: New file.
	* sysdeps/ia64/fpu/e_expl.c: New file.
	* sysdeps/ia64/fpu/e_fmod.S: New file.
	* sysdeps/ia64/fpu/e_fmodf.S: New file.
	* sysdeps/ia64/fpu/e_fmodl.S: New file.
	* sysdeps/ia64/fpu/e_hypot.S: New file.
	* sysdeps/ia64/fpu/e_hypotf.S: New file.
	* sysdeps/ia64/fpu/e_hypotl.S: New file.
	* sysdeps/ia64/fpu/e_log.S: New file.
	* sysdeps/ia64/fpu/e_log10.c: New file.
	* sysdeps/ia64/fpu/e_log10f.c: New file.
	* sysdeps/ia64/fpu/e_log10l.c: New file.
	* sysdeps/ia64/fpu/e_logf.S: New file.
	* sysdeps/ia64/fpu/e_logl.c: New file.
	* sysdeps/ia64/fpu/e_pow.S: New file.
	* sysdeps/ia64/fpu/e_powf.S: New file.
	* sysdeps/ia64/fpu/e_powl.S: New file.
	* sysdeps/ia64/fpu/e_rem_pio2.c: New file.
	* sysdeps/ia64/fpu/e_rem_pio2f.c: New file.
	* sysdeps/ia64/fpu/e_remainder.S: New file.
	* sysdeps/ia64/fpu/e_remainderf.S: New file.
	* sysdeps/ia64/fpu/e_remainderl.S: New file.
	* sysdeps/ia64/fpu/e_scalb.S: New file.
	* sysdeps/ia64/fpu/e_scalbf.S: New file.
	* sysdeps/ia64/fpu/e_scalbl.S: New file.
	* sysdeps/ia64/fpu/e_sinh.S: New file.
	* sysdeps/ia64/fpu/e_sinhf.S: New file.
	* sysdeps/ia64/fpu/e_sinhl.S: New file.
	* sysdeps/ia64/fpu/e_sqrt.S: New file.
	* sysdeps/ia64/fpu/e_sqrtf.S: New file.
	* sysdeps/ia64/fpu/e_sqrtl.S: New file.
	* sysdeps/ia64/fpu/k_rem_pio2.c: New file.
	* sysdeps/ia64/fpu/k_rem_pio2f.c: New file.
	* sysdeps/ia64/fpu/k_rem_pio2l.c: New file.
	* sysdeps/ia64/fpu/libm_atan2_reg.S: New file.
	* sysdeps/ia64/fpu/libm_error.c: New file.
	* sysdeps/ia64/fpu/libm_frexp4.S: New file.
	* sysdeps/ia64/fpu/libm_frexp4f.S: New file.
	* sysdeps/ia64/fpu/libm_frexp4l.S: New file.
	* sysdeps/ia64/fpu/libm_reduce.S: New file.
	* sysdeps/ia64/fpu/libm_support.h: New file.
	* sysdeps/ia64/fpu/libm_tan.S: New file.
	* sysdeps/ia64/fpu/s_atan.S: New file.
	* sysdeps/ia64/fpu/s_atanf.S: New file.
	* sysdeps/ia64/fpu/s_atanl.S: New file.
	* sysdeps/ia64/fpu/s_cbrt.S: New file.
	* sysdeps/ia64/fpu/s_cbrtf.S: New file.
	* sysdeps/ia64/fpu/s_cbrtl.S: New file.
	* sysdeps/ia64/fpu/s_ceil.S: New file.
	* sysdeps/ia64/fpu/s_ceilf.S: New file.
	* sysdeps/ia64/fpu/s_ceill.S: New file.
	* sysdeps/ia64/fpu/s_cos.S: New file.
	* sysdeps/ia64/fpu/s_cosf.S: New file.
	* sysdeps/ia64/fpu/s_cosl.S: New file.
	* sysdeps/ia64/fpu/s_expm1.S: New file.
	* sysdeps/ia64/fpu/s_expm1f.S: New file.
	* sysdeps/ia64/fpu/s_expm1l.S: New file.
	* sysdeps/ia64/fpu/s_floor.S: New file.
	* sysdeps/ia64/fpu/s_floorf.S: New file.
	* sysdeps/ia64/fpu/s_floorl.S: New file.
	* sysdeps/ia64/fpu/s_frexp.c: New file.
	* sysdeps/ia64/fpu/s_frexpf.c: New file.
	* sysdeps/ia64/fpu/s_frexpl.c: New file.
	* sysdeps/ia64/fpu/s_ilogb.S: New file.
	* sysdeps/ia64/fpu/s_ilogbf.S: New file.
	* sysdeps/ia64/fpu/s_ilogbl.S: New file.
	* sysdeps/ia64/fpu/s_ldexp.S: New file.
	* sysdeps/ia64/fpu/s_ldexpf.S: New file.
	* sysdeps/ia64/fpu/s_ldexpl.S: New file.
	* sysdeps/ia64/fpu/s_log1p.S: New file.
	* sysdeps/ia64/fpu/s_log1pf.S: New file.
	* sysdeps/ia64/fpu/s_log1pl.S: New file.
	* sysdeps/ia64/fpu/s_logb.S: New file.
	* sysdeps/ia64/fpu/s_logbf.S: New file.
	* sysdeps/ia64/fpu/s_logbl.S: New file.
	* sysdeps/ia64/fpu/s_matherrf.c: New file.
	* sysdeps/ia64/fpu/s_matherrl.c: New file.
	* sysdeps/ia64/fpu/s_modf.S: New file.
	* sysdeps/ia64/fpu/s_modff.S: New file.
	* sysdeps/ia64/fpu/s_modfl.S: New file.
	* sysdeps/ia64/fpu/s_nearbyint.S: New file.
	* sysdeps/ia64/fpu/s_nearbyintf.S: New file.
	* sysdeps/ia64/fpu/s_nearbyintl.S: New file.
	* sysdeps/ia64/fpu/s_rint.S: New file.
	* sysdeps/ia64/fpu/s_rintf.S: New file.
	* sysdeps/ia64/fpu/s_rintl.S: New file.
	* sysdeps/ia64/fpu/s_round.S: New file.
	* sysdeps/ia64/fpu/s_roundf.S: New file.
	* sysdeps/ia64/fpu/s_roundl.S: New file.
	* sysdeps/ia64/fpu/s_scalbn.S: New file.
	* sysdeps/ia64/fpu/s_scalbnf.S: New file.
	* sysdeps/ia64/fpu/s_scalbnl.S: New file.
	* sysdeps/ia64/fpu/s_significand.S: New file.
	* sysdeps/ia64/fpu/s_significandf.S: New file.
	* sysdeps/ia64/fpu/s_significandl.S: New file.
	* sysdeps/ia64/fpu/s_sin.c: New file.
	* sysdeps/ia64/fpu/s_sincos.c: New file.
	* sysdeps/ia64/fpu/s_sincosf.c: New file.
	* sysdeps/ia64/fpu/s_sincosl.c: New file.
	* sysdeps/ia64/fpu/s_sinf.c: New file.
	* sysdeps/ia64/fpu/s_sinl.c: New file.
	* sysdeps/ia64/fpu/s_tan.S: New file.
	* sysdeps/ia64/fpu/s_tanf.S: New file.
	* sysdeps/ia64/fpu/s_tanl.S: New file.
	* sysdeps/ia64/fpu/s_trunc.S: New file.
	* sysdeps/ia64/fpu/s_truncf.S: New file.
	* sysdeps/ia64/fpu/s_truncl.S: New file.
	* sysdeps/ia64/fpu/w_acos.c: New file.
	* sysdeps/ia64/fpu/w_acosf.c: New file.
	* sysdeps/ia64/fpu/w_acosl.c: New file.
	* sysdeps/ia64/fpu/w_asin.c: New file.
	* sysdeps/ia64/fpu/w_asinf.c: New file.
	* sysdeps/ia64/fpu/w_asinl.c: New file.
	* sysdeps/ia64/fpu/w_atan2.c: New file.
	* sysdeps/ia64/fpu/w_atan2f.c: New file.
	* sysdeps/ia64/fpu/w_atan2l.c: New file.
	* sysdeps/ia64/fpu/w_cosh.c: New file.
	* sysdeps/ia64/fpu/w_coshf.c: New file.
	* sysdeps/ia64/fpu/w_coshl.c: New file.
	* sysdeps/ia64/fpu/w_exp.c: New file.
	* sysdeps/ia64/fpu/w_expf.c: New file.
	* sysdeps/ia64/fpu/w_fmod.c: New file.
	* sysdeps/ia64/fpu/w_fmodf.c: New file.
	* sysdeps/ia64/fpu/w_fmodl.c: New file.
	* sysdeps/ia64/fpu/w_hypot.c: New file.
	* sysdeps/ia64/fpu/w_hypotf.c: New file.
	* sysdeps/ia64/fpu/w_hypotl.c: New file.
	* sysdeps/ia64/fpu/w_log.c: New file.
	* sysdeps/ia64/fpu/w_log10.c: New file.
	* sysdeps/ia64/fpu/w_log10f.c: New file.
	* sysdeps/ia64/fpu/w_log10l.c: New file.
	* sysdeps/ia64/fpu/w_logf.c: New file.
	* sysdeps/ia64/fpu/w_logl.c: New file.
	* sysdeps/ia64/fpu/w_pow.c: New file.
	* sysdeps/ia64/fpu/w_powf.c: New file.
	* sysdeps/ia64/fpu/w_powl.c: New file.
	* sysdeps/ia64/fpu/w_remainder.c: New file.
	* sysdeps/ia64/fpu/w_remainderf.c: New file.
	* sysdeps/ia64/fpu/w_remainderl.c: New file.
	* sysdeps/ia64/fpu/w_scalb.c: New file.
	* sysdeps/ia64/fpu/w_scalbf.c: New file.
	* sysdeps/ia64/fpu/w_scalbl.c: New file.
	* sysdeps/ia64/fpu/w_sqrt.c: New file.
	* sysdeps/ia64/fpu/w_sqrtf.c: New file.
	* sysdeps/ia64/fpu/w_sqrtl.c: New file.
	* sysdeps/ia64/fpu/libm-test-ulps: Adjust for long double
	implementation.
	* sysdeps/ia64/fpu/bits/mathdef.h: Correct float_t and double_t types.
	Change FP_ILOGBNAN for new implementation.
	* Verions.def: Add 2.2.3 versions.
Diffstat (limited to 'sysdeps/ia64/fpu/s_atanl.S')
-rw-r--r--sysdeps/ia64/fpu/s_atanl.S1994
1 files changed, 1994 insertions, 0 deletions
diff --git a/sysdeps/ia64/fpu/s_atanl.S b/sysdeps/ia64/fpu/s_atanl.S
new file mode 100644
index 0000000000..0192ac6a18
--- /dev/null
+++ b/sysdeps/ia64/fpu/s_atanl.S
@@ -0,0 +1,1994 @@
+.file "atanl.s"
+
+// Copyright (c) 2000, 2001, Intel Corporation
+// All rights reserved.
+// 
+// Contributed 2/2/2000 by John Harrison, Ted Kubaska, Bob Norin, Shane Story,
+// and Ping Tak Peter Tang of the Computational Software Lab, Intel Corporation.
+// 
+// WARRANTY DISCLAIMER
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS 
+// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 
+// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+// 
+// Intel Corporation is the author of this code, and requests that all
+// problem reports or change requests be submitted to it directly at 
+// http://developer.intel.com/opensource.
+//
+//
+// *********************************************************************
+//
+// History
+// 2/02/00  (hand-optimized)
+// 4/04/00  Unwind support added
+// 8/15/00  Bundle added after call to __libm_error_support to properly
+//          set [the previously overwritten] GR_Parameter_RESULT.
+//
+// *********************************************************************
+//
+// Function:   atanl(x) = inverse tangent(x), for double extended x values
+// Function:   atan2l(y,x) = atan(y/x), for double extended x values
+//
+// *********************************************************************
+//
+// Resources Used:
+//
+//    Floating-Point Registers: f8 (Input and Return Value)
+//                              f9-f15
+//                              f32-f79
+//
+//    General Purpose Registers:
+//      r32-r48
+//      r49,r50,r51,r52 (Arguments to error support for 0,0 case)
+//
+//    Predicate Registers:      p6-p15
+//
+// *********************************************************************
+//
+// IEEE Special Conditions:
+//
+//    Denormal  fault raised on denormal inputs
+//    Underflow exceptions may occur 
+//    Special error handling for the y=0 and x=0 case
+//    Inexact raised when appropriate by algorithm
+//
+//    atanl(SNaN) = QNaN
+//    atanl(QNaN) = QNaN
+//    atanl(+/-0) = +/- 0
+//    atanl(+/-Inf) = +/-pi/2 
+//
+//    atan2l(Any NaN for x or y) = QNaN
+//    atan2l(+/-0,x) = +/-0 for x > 0 
+//    atan2l(+/-0,x) = +/-pi for x < 0 
+//    atan2l(+/-0,+0) = +/-0 
+//    atan2l(+/-0,-0) = +/-pi 
+//    atan2l(y,+/-0) = pi/2 y > 0
+//    atan2l(y,+/-0) = -pi/2 y < 0
+//    atan2l(+/-y, Inf) = +/-0 for finite y > 0
+//    atan2l(+/-Inf, x) = +/-pi/2 for finite x 
+//    atan2l(+/-y, -Inf) = +/-pi for finite  y > 0 
+//    atan2l(+/-Inf, Inf) = +/-pi/4
+//    atan2l(+/-Inf, -Inf) = +/-3pi/4
+//
+// *********************************************************************
+//
+// Mathematical Description
+// ---------------------------
+//
+// The function ATANL( Arg_Y, Arg_X ) returns the "argument"
+// or the "phase" of the complex number
+//
+//           Arg_X + i Arg_Y
+//
+// or equivalently, the angle in radians from the positive
+// x-axis to the line joining the origin and the point
+// (Arg_X,Arg_Y)
+//
+//
+//        (Arg_X, Arg_Y) x
+//                        \ 
+//                \ 
+//                 \ 
+//                  \ 
+//                   \ angle between is ATANL(Arg_Y,Arg_X)
+
+
+
+
+//                    \ 
+//                     ------------------> X-axis
+
+//                   Origin
+//
+// Moreover, this angle is reported in the range [-pi,pi] thus
+//
+//      -pi <= ATANL( Arg_Y, Arg_X ) <= pi.
+//
+// From the geometry, it is easy to define ATANL when one of
+// Arg_X or Arg_Y is +-0 or +-inf:
+//
+//
+//      \ Y |
+//     X \  |  +0  | -0  |  +inf |  -inf  |  finite non-zero
+//        \ |      |     |       |        |
+//    ______________________________________________________
+//          |            |       |        |
+//     +-0  |   Invalid/ |  pi/2 | -pi/2  |  sign(Y)*pi/2
+//          |    qNaN    |       |        |
+//  --------------------------------------------------------
+//          |      |     |       |        |
+//     +inf |  +0  | -0  |  pi/4 | -pi/4  |  sign(Y)*0
+//  --------------------------------------------------------
+//          |      |     |       |        |
+//     -inf |  +pi | -pi | 3pi/4 | -3pi/4 |  sign(Y)*pi
+//  --------------------------------------------------------
+//   finite |    X>0?    |  pi/2 | -pi/2  |  normal case
+//  non-zero| sign(Y)*0: |       |        |
+//       | sign(Y)*pi |       |        |
+//
+//
+// One must take note that ATANL is NOT the arctangent of the
+// value Arg_Y/Arg_X; but rather ATANL and arctan are related
+// in a slightly more complicated way as follows:
+//
+// Let U := max(|Arg_X|, |Arg_Y|);  V := min(|Arg_X|, |Arg_Y|);
+// sign_X be the sign bit of Arg_X, i.e., sign_X is 0 or 1;
+// s_X    be the sign     of Arg_X, i.e., s_X = (-1)^sign_X;
+//
+// sign_Y be the sign bit of Arg_Y, i.e., sign_Y is 0 or 1;
+// s_Y    be the sign     of Arg_Y, i.e., s_Y = (-1)^sign_Y;
+//
+// swap   be 0  if |Arg_X| >= |Arg_Y|  and 1 otherwise.
+//
+// Then, ATANL(Arg_Y, Arg_X) =
+//
+//       /    arctan(V/U)     \      sign_X = 0 & swap = 0
+//       | pi/2 - arctan(V/U) |      sign_X = 0 & swap = 1
+// s_Y * |                    |
+//       |  pi  - arctan(V/U) |      sign_X = 1 & swap = 0
+//       \ pi/2 + arctan(V/U) /      sign_X = 1 & swap = 1
+//
+//
+// This relationship also suggest that the algorithm's major
+// task is to calculate arctan(V/U) for 0 < V <= U; and the
+// final Result is given by
+//
+//      s_Y * { (P_hi + P_lo) + sigma * arctan(V/U) }
+//
+// where
+//
+//   (P_hi,P_lo) represents M(sign_X,swap)*(pi/2) accurately
+//
+//   M(sign_X,swap) = 0  for sign_X = 0 and swap = 0
+//              1  for swap   = 1
+//              2  for sign_X = 1 and swap = 0
+//
+// and
+//
+//   sigma = { (sign_X  XOR  swap) :  -1.0 : 1.0 }
+//
+//      =  (-1) ^ ( sign_X XOR swap )
+//
+// Both (P_hi,P_lo) and sigma can be stored in a table and fetched
+// using (sign_X,swap) as an index. (P_hi, P_lo) can be stored as a
+// double-precision, and single-precision pair; and sigma can
+// obviously be just a single-precision number.
+//
+// In the algorithm we propose, arctan(V/U) is calculated to high accuracy
+// as A_hi + A_lo. Consequently, the Result ATANL( Arg_Y, Arg_X ) is
+// given by
+//
+//    s_Y*P_hi + s_Y*sigma*A_hi + s_Y*(sigma*A_lo + P_lo)
+//
+// We now discuss the calculation of arctan(V/U) for 0 < V <= U.
+//
+// For (V/U) < 2^(-3), we use a simple polynomial of the form
+//
+//      z + z^3*(P_1 + z^2*(P_2 + z^2*(P_3 + ... + P_8)))
+//
+// where z = V/U.
+//
+// For the sake of accuracy, the first term "z" must approximate V/U to
+// extra precision. For z^3 and higher power, a working precision
+// approximation to V/U suffices. Thus, we obtain:
+//
+//      z_hi + z_lo = V/U  to extra precision and
+//      z           = V/U  to working precision
+//
+// The value arctan(V/U) is delivered as two pieces (A_hi, A_lo)
+//
+//      (A_hi,A_lo) = (z_hi, z^3*(P_1 + ... + P_8) + z_lo).
+//
+//
+// For 2^(-3) <= (V/U) <= 1, we use a table-driven approach.
+// Consider
+//
+//      (V/U) = 2^k * 1.b_1 b_2 .... b_63 b_64 b_65 ....
+//
+// Define
+//
+//       z_hi = 2^k * 1.b_1 b_2 b_3 b_4 1
+//
+// then
+//                                            /                \ 
+//                                            |  (V/U) - z_hi  |
+
+//      arctan(V/U) = arctan(z_hi) + acrtan| -------------- |
+//                                            | 1 + (V/U)*z_hi |
+//                                            \                /
+//
+//                                            /                \ 
+//                                            |   V - z_hi*U   |
+
+//                  = arctan(z_hi) + acrtan| -------------- |
+//                                            |   U + V*z_hi   |
+//                                            \                /
+//
+//                  = arctan(z_hi) + acrtan( V' / U' )
+//
+//
+// where
+//
+//      V' = V - U*z_hi;   U' = U + V*z_hi.
+//
+// Let
+//
+//      w_hi + w_lo  = V'/U' to extra precision and
+//           w       = V'/U' to working precision
+//
+// then we can approximate arctan(V'/U') by
+//
+//      arctan(V'/U') = w_hi + w_lo
+//                     + w^3*(Q_1 + w^2*(Q_2 + w^2*(Q_3 + w^2*Q_4)))
+//
+//                       = w_hi + w_lo + poly
+//
+// Finally, arctan(z_hi) is calculated beforehand and stored in a table
+// as Tbl_hi, Tbl_lo. Thus,
+//
+//      (A_hi, A_lo) = (Tbl_hi, w_hi+(poly+(w_lo+Tbl_lo)))
+//
+// This completes the mathematical description.
+//
+//
+// Algorithm
+// -------------
+//
+// Step 0. Check for unsupported format.
+//
+//    If
+//       ( expo(Arg_X) not zero AND msb(Arg_X) = 0 ) OR
+//       ( expo(Arg_Y) not zero AND msb(Arg_Y) = 0 )
+//
+//    then one of the arguments is unsupported. Generate an
+//    invalid and return qNaN.
+//
+// Step 1. Initialize
+//
+//    Normalize Arg_X and Arg_Y and set the following
+//
+//    sign_X :=  sign_bit(Arg_X)
+//    s_Y    := (sign_bit(Arg_Y)==0? 1.0 : -1.0)
+//    swap   := (|Arg_X| >= |Arg_Y|?   0 :  1  )
+//    U      := max( |Arg_X|, |Arg_Y| )
+//    V      := min( |Arg_X|, |Arg_Y| )
+//
+//    execute: frcap E, pred, V, U
+//    If pred is 0, go to Step 5 for special cases handling.
+//
+// Step 2. Decide on branch.
+//
+//    Q := E * V
+//    If Q < 2^(-3) go to Step 4 for simple polynomial case.
+//
+// Step 3. Table-driven algorithm.
+//
+//    Q is represented as
+//
+//      2^(-k) * 1.b_1 b_2 b_3 ... b_63; k = 0,-1,-2,-3
+//
+// and that if k = 0, b_1 = b_2 = b_3 = b_4 = 0.
+//
+// Define
+//
+//      z_hi := 2^(-k) * 1.b_1 b_2 b_3 b_4 1
+//
+// (note that there are 49 possible values of z_hi).
+//
+//      ...We now calculate V' and U'. While V' is representable
+//      ...as a 64-bit number because of cancellation, U' is
+//      ...not in general a 64-bit number. Obtaining U' accurately
+//      ...requires two working precision numbers
+//
+//      U_prime_hi := U + V * z_hi            ...WP approx. to U'
+//      U_prime_lo := ( U - U_prime_hi ) + V*z_hi ...observe order
+//      V_prime    := V - U * z_hi             ...this is exact
+//
+//         C_hi := frcpa (1.0, U_prime_hi)  ...C_hi approx 1/U'_hi
+//
+//      loop 3 times
+//         C_hi := C_hi + C_hi*(1.0 - C_hi*U_prime_hi)
+//
+//      ...at this point C_hi is (1/U_prime_hi) to roughly 64 bits
+//
+//      w_hi := V_prime * C_hi     ...w_hi is V_prime/U_prime to
+//                     ...roughly working precision
+//
+//         ...note that we want w_hi + w_lo to approximate
+//      ...V_prime/(U_prime_hi + U_prime_lo) to extra precision
+//         ...but for now, w_hi is good enough for the polynomial
+//      ...calculation.
+//
+//         wsq  := w_hi*w_hi
+//      poly := w_hi*wsq*(Q_1 + wsq*(Q_2 + wsq*(Q_3 + wsq*Q_4)))
+//
+//      Fetch
+//      (Tbl_hi, Tbl_lo) = atan(z_hi) indexed by (k,b_1,b_2,b_3,b_4)
+//      ...Tbl_hi is a double-precision number
+//      ...Tbl_lo is a single-precision number
+//
+//         (P_hi, P_lo) := M(sign_X,swap)*(Pi_by_2_hi, Pi_by_2_lo)
+//      ...as discussed previous. Again; the implementation can
+//      ...chose to fetch P_hi and P_lo from a table indexed by
+//      ...(sign_X, swap).
+//      ...P_hi is a double-precision number;
+//      ...P_lo is a single-precision number.
+//
+//      ...calculate w_lo so that w_hi + w_lo is V'/U' accurately
+//         w_lo := ((V_prime - w_hi*U_prime_hi) -
+//              w_hi*U_prime_lo) * C_hi     ...observe order
+//
+//
+//      ...Ready to deliver arctan(V'/U') as A_hi, A_lo
+//      A_hi := Tbl_hi
+//      A_lo := w_hi + (poly + (Tbl_lo + w_lo)) ...observe order
+//
+//      ...Deliver final Result
+//      ...s_Y*P_hi + s_Y*sigma*A_hi + s_Y*(sigma*A_lo + P_lo)
+//
+//      sigma := ( (sign_X XOR swap) ? -1.0 : 1.0 )
+//      ...sigma can be obtained by a table lookup using
+//      ...(sign_X,swap) as index and stored as single precision
+//         ...sigma should be calculated earlier
+//
+//      P_hi := s_Y*P_hi
+//      A_hi := s_Y*A_hi
+//
+//      Res_hi := P_hi + sigma*A_hi     ...this is exact because
+//                          ...both P_hi and Tbl_hi
+//                          ...are double-precision
+//                          ...and |Tbl_hi| > 2^(-4)
+//                          ...P_hi is either 0 or
+//                          ...between (1,4)
+//
+//      Res_lo := sigma*A_lo + P_lo
+//
+//      Return Res_hi + s_Y*Res_lo in user-defined rounding control
+//
+// Step 4. Simple polynomial case.
+//
+//    ...E and Q are inherited from Step 2.
+//
+//    A_hi := Q     ...Q is inherited from Step 2 Q approx V/U
+//
+//    loop 3 times
+//       E := E + E2(1.0 - E*U1
+//    ...at this point E approximates 1/U to roughly working precision
+//
+//    z := V * E     ...z approximates V/U to roughly working precision
+//    zsq := z * z
+//    z8 := zsq * zsq; z8 := z8 * z8
+//
+//    poly1 := P_4 + zsq*(P_5 + zsq*(P_6 + zsq*(P_7 + zsq*P_8)))
+//    poly2 := zsq*(P_1 + zsq*(P_2 + zsq*P_3))
+//
+//    poly  := poly1 + z8*poly2
+//
+//    z_lo := (V - A_hi*U)*E
+//
+//    A_lo := z*poly + z_lo
+//    ...A_hi, A_lo approximate arctan(V/U) accurately
+//
+//    (P_hi, P_lo) := M(sign_X,swap)*(Pi_by_2_hi, Pi_by_2_lo)
+//    ...one can store the M(sign_X,swap) as single precision
+//    ...values
+//
+//    ...Deliver final Result
+//    ...s_Y*P_hi + s_Y*sigma*A_hi + s_Y*(sigma*A_lo + P_lo)
+//
+//    sigma := ( (sign_X XOR swap) ? -1.0 : 1.0 )
+//    ...sigma can be obtained by a table lookup using
+//    ...(sign_X,swap) as index and stored as single precision
+//    ...sigma should be calculated earlier
+//
+//    P_hi := s_Y*P_hi
+//    A_hi := s_Y*A_hi
+//
+//    Res_hi := P_hi + sigma*A_hi          ...need to compute
+//                          ...P_hi + sigma*A_hi
+//                          ...exactly
+//
+//    tmp    := (P_hi - Res_hi) + sigma*A_hi
+//
+//    Res_lo := s_Y*(sigma*A_lo + P_lo) + tmp
+//
+//    Return Res_hi + Res_lo in user-defined rounding control
+//
+// Step 5. Special Cases
+//
+//    If pred is 0 where pred is obtained in
+//        frcap E, pred, V, U
+//
+//    we are in one of those special cases of 0,+-inf or NaN
+//
+//    If one of U and V is NaN, return U+V (which will generate
+//    invalid in case one is a signaling NaN). Otherwise,
+//    return the Result as described in the table
+//
+//
+//
+//      \ Y |
+//     X \  |  +0  | -0  |  +inf |  -inf  |  finite non-zero
+//        \ |      |     |       |        |
+//    ______________________________________________________
+//          |            |       |        |
+//     +-0  |   Invalid/ |  pi/2 | -pi/2  |  sign(Y)*pi/2
+//          |    qNaN    |       |        |
+//  --------------------------------------------------------
+//          |      |     |       |        |
+//     +inf |  +0  | -0  |  pi/4 | -pi/4  |  sign(Y)*0
+//  --------------------------------------------------------
+//          |      |     |       |        |
+//     -inf |  +pi | -pi | 3pi/4 | -3pi/4 |  sign(Y)*pi
+//  --------------------------------------------------------
+//   finite |    X>0?    |  pi/2 | -pi/2  |
+//  non-zero| sign(Y)*0: |       |        |      N/A
+//       | sign(Y)*pi |       |        |
+//
+//
+
+#include "libm_support.h"
+
+ArgY_orig   =   f8
+Result      =   f8
+FR_RESULT   =   f8
+ArgX_orig   =   f9
+ArgX        =   f10
+FR_X        =   f10
+ArgY        =   f11
+FR_Y        =   f11
+s_Y         =   f12
+U           =   f13
+V           =   f14
+E           =   f15
+Q           =   f32
+z_hi        =   f33
+U_prime_hi  =   f34
+U_prime_lo  =   f35
+V_prime     =   f36
+C_hi        =   f37
+w_hi        =   f38
+w_lo        =   f39
+wsq         =   f40
+poly        =   f41
+Tbl_hi      =   f42
+Tbl_lo      =   f43
+P_hi        =   f44
+P_lo        =   f45
+A_hi        =   f46
+A_lo        =   f47
+sigma       =   f48
+Res_hi      =   f49
+Res_lo      =   f50
+Z           =   f52
+zsq         =   f53
+z8          =   f54
+poly1       =   f55
+poly2       =   f56
+z_lo        =   f57
+tmp         =   f58
+P_1         =   f59
+Q_1         =   f60
+P_2         =   f61
+Q_2         =   f62
+P_3         =   f63
+Q_3         =   f64
+P_4         =   f65
+Q_4         =   f66
+P_5         =   f67
+P_6         =   f68
+P_7         =   f69
+P_8         =   f70
+TWO_TO_NEG3 =   f71
+U_hold      =   f72
+C_hi_hold   =   f73
+E_hold      =   f74
+M           =   f75
+ArgX_abs    =   f76
+ArgY_abs    =   f77
+Result_lo   =   f78
+A_temp      =   f79
+GR_SAVE_PFS   = r33
+GR_SAVE_B0    = r34
+GR_SAVE_GP    = r35
+sign_X        = r36
+sign_Y        = r37 
+swap          = r38 
+table_ptr1    = r39 
+table_ptr2    = r40 
+k             = r41 
+lookup        = r42 
+exp_ArgX      = r43 
+exp_ArgY      = r44 
+exponent_Q    = r45 
+significand_Q = r46 
+special       = r47 
+special1      = r48 
+GR_Parameter_X      = r49
+GR_Parameter_Y      = r50
+GR_Parameter_RESULT = r51
+GR_Parameter_TAG    = r52
+int_temp            = r52
+
+#ifdef _LIBC
+.rodata
+#else
+.data
+#endif
+.align 64 
+
+Constants_atan:
+ASM_TYPE_DIRECTIVE(Constants_atan,@object)
+data4    0x54442D18, 0x3FF921FB, 0x248D3132, 0x3E000000
+//       double pi/2, single lo_pi/2, two**(-3)
+data4    0xAAAAAAA3, 0xAAAAAAAA, 0x0000BFFD, 0x00000000 // P_1
+data4    0xCCCC54B2, 0xCCCCCCCC, 0x00003FFC, 0x00000000 // P_2
+data4    0x47E4D0C2, 0x92492492, 0x0000BFFC, 0x00000000 // P_3
+data4    0x58870889, 0xE38E38E0, 0x00003FFB, 0x00000000 // P_4
+data4    0x290149F8, 0xBA2E895B, 0x0000BFFB, 0x00000000 // P_5
+data4    0x250F733D, 0x9D88E6D4, 0x00003FFB, 0x00000000 // P_6
+data4    0xFB8745A0, 0x884E51FF, 0x0000BFFB, 0x00000000 // P_7
+data4    0x394396BD, 0xE1C7412B, 0x00003FFA, 0x00000000 // P_8
+data4    0xAAAAA52F, 0xAAAAAAAA, 0x0000BFFD, 0x00000000 // Q_1
+data4    0xC75B60D3, 0xCCCCCCCC, 0x00003FFC, 0x00000000 // Q_2
+data4    0x011F1940, 0x924923AD, 0x0000BFFC, 0x00000000 // Q_3
+data4    0x2A5F89BD, 0xE36F716D, 0x00003FFB, 0x00000000 // Q_4
+//
+//    Entries Tbl_hi  (double precision)
+//    B = 1+Index/16+1/32  Index = 0
+//    Entries Tbl_lo (single precision)
+//    B = 1+Index/16+1/32  Index = 0
+//
+data4   0xA935BD8E, 0x3FE9A000, 0x23ACA08F, 0x00000000
+//
+//    Entries Tbl_hi  (double precision) Index = 0,1,...,15
+//    B = 2^(-1)*(1+Index/16+1/32)
+//    Entries Tbl_lo (single precision)
+//    Index = 0,1,...,15  B = 2^(-1)*(1+Index/16+1/32)
+//
+data4   0x7F175A34, 0x3FDE77EB, 0x238729EE, 0x00000000
+data4   0x73C1A40B, 0x3FE0039C, 0x249334DB, 0x00000000
+data4   0x5B5B43DA, 0x3FE0C614, 0x22CBA7D1, 0x00000000
+data4   0x88BE7C13, 0x3FE1835A, 0x246310E7, 0x00000000
+data4   0xE2CC9E6A, 0x3FE23B71, 0x236210E5, 0x00000000
+data4   0x8406CBCA, 0x3FE2EE62, 0x2462EAF5, 0x00000000
+data4   0x1CD41719, 0x3FE39C39, 0x24B73EF3, 0x00000000
+data4   0x5B795B55, 0x3FE44506, 0x24C11260, 0x00000000
+data4   0x5BB6EC04, 0x3FE4E8DE, 0x242519EE, 0x00000000
+data4   0x1F732FBA, 0x3FE587D8, 0x24D4346C, 0x00000000
+data4   0x115D7B8D, 0x3FE6220D, 0x24ED487B, 0x00000000
+data4   0x920B3D98, 0x3FE6B798, 0x2495FF1E, 0x00000000
+data4   0x8FBA8E0F, 0x3FE74897, 0x223D9531, 0x00000000
+data4   0x289FA093, 0x3FE7D528, 0x242B0411, 0x00000000
+data4   0x576CC2C5, 0x3FE85D69, 0x2335B374, 0x00000000
+data4   0xA99CC05D, 0x3FE8E17A, 0x24C27CFB, 0x00000000
+//
+//    Entries Tbl_hi  (double precision) Index = 0,1,...,15
+//    B = 2^(-2)*(1+Index/16+1/32)
+//    Entries Tbl_lo (single precision)
+//    Index = 0,1,...,15  B = 2^(-2)*(1+Index/16+1/32)
+//
+data4    0x510665B5, 0x3FD025FA, 0x24263482, 0x00000000
+data4    0x362431C9, 0x3FD1151A, 0x242C8DC9, 0x00000000
+data4    0x67E47C95, 0x3FD20255, 0x245CF9BA, 0x00000000
+data4    0x7A823CFE, 0x3FD2ED98, 0x235C892C, 0x00000000
+data4    0x29271134, 0x3FD3D6D1, 0x2389BE52, 0x00000000
+data4    0x586890E6, 0x3FD4BDEE, 0x24436471, 0x00000000
+data4    0x175E0F4E, 0x3FD5A2E0, 0x2389DBD4, 0x00000000
+data4    0x9F5FA6FD, 0x3FD68597, 0x2476D43F, 0x00000000
+data4    0x52817501, 0x3FD76607, 0x24711774, 0x00000000
+data4    0xB8DF95D7, 0x3FD84422, 0x23EBB501, 0x00000000
+data4    0x7CD0C662, 0x3FD91FDE, 0x23883A0C, 0x00000000
+data4    0x66168001, 0x3FD9F930, 0x240DF63F, 0x00000000
+data4    0x5422058B, 0x3FDAD00F, 0x23FE261A, 0x00000000
+data4    0x378624A5, 0x3FDBA473, 0x23A8CD0E, 0x00000000
+data4    0x0AAD71F8, 0x3FDC7655, 0x2422D1D0, 0x00000000
+data4    0xC9EC862B, 0x3FDD45AE, 0x2344A109, 0x00000000
+//
+//    Entries Tbl_hi  (double precision) Index = 0,1,...,15
+//    B = 2^(-3)*(1+Index/16+1/32)
+//    Entries Tbl_lo (single precision)
+//    Index = 0,1,...,15  B = 2^(-3)*(1+Index/16+1/32)
+//
+data4    0x84212B3D, 0x3FC068D5, 0x239874B6, 0x00000000
+data4    0x41060850, 0x3FC16465, 0x2335E774, 0x00000000
+data4    0x171A535C, 0x3FC25F6E, 0x233E36BE, 0x00000000
+data4    0xEDEB99A3, 0x3FC359E8, 0x239680A3, 0x00000000
+data4    0xC6092A9E, 0x3FC453CE, 0x230FB29E, 0x00000000
+data4    0xBA11570A, 0x3FC54D18, 0x230C1418, 0x00000000
+data4    0xFFB3AA73, 0x3FC645BF, 0x23F0564A, 0x00000000
+data4    0xE8A7D201, 0x3FC73DBD, 0x23D4A5E1, 0x00000000
+data4    0xE398EBC7, 0x3FC8350B, 0x23D4ADDA, 0x00000000
+data4    0x7D050271, 0x3FC92BA3, 0x23BCB085, 0x00000000
+data4    0x601081A5, 0x3FCA217E, 0x23BC841D, 0x00000000
+data4    0x574D780B, 0x3FCB1696, 0x23CF4A8E, 0x00000000
+data4    0x4D768466, 0x3FCC0AE5, 0x23BECC90, 0x00000000
+data4    0x4E1D5395, 0x3FCCFE65, 0x2323DCD2, 0x00000000
+data4    0x864C9D9D, 0x3FCDF110, 0x23F53F3A, 0x00000000
+data4    0x451D980C, 0x3FCEE2E1, 0x23CCB11F, 0x00000000
+
+data4    0x54442D18, 0x400921FB, 0x33145C07, 0x3CA1A626 // PI two doubles
+data4    0x54442D18, 0x3FF921FB, 0x33145C07, 0x3C91A626 // PI_by_2 two dbles
+data4    0x54442D18, 0x3FE921FB, 0x33145C07, 0x3C81A626 // PI_by_4 two dbles
+data4    0x7F3321D2, 0x4002D97C, 0x4C9E8A0A, 0x3C9A7939 // 3PI_by_4 two dbles
+ASM_SIZE_DIRECTIVE(Constants_atan)
+
+
+.text
+.proc atanl#
+.global atanl#
+.align 64
+
+atanl: 
+{ .mfb
+	nop.m 999
+(p0)   mov ArgX_orig = f1 
+(p0)   br.cond.sptk atan2l ;;
+}
+.endp atanl
+ASM_SIZE_DIRECTIVE(atanl)
+
+.text
+.proc atan2l#
+.global atan2l#
+#ifdef _LIBC
+.proc __atan2l#
+.global __atan2l#
+.proc __ieee754_atan2l#
+.global __ieee754_atan2l#
+#endif
+.align 64 
+
+
+atan2l:
+#ifdef _LIBC
+__atan2l:
+__ieee754_atan2l:
+#endif
+{ .mfi
+alloc r32 = ar.pfs, 0, 17 , 4, 0
+(p0)  mov   ArgY = ArgY_orig
+}
+{ .mfi
+	nop.m 999
+(p0)  mov   ArgX = ArgX_orig
+	nop.i 999
+};;
+{ .mfi
+	nop.m 999
+(p0)   fclass.m.unc p7,p0 = ArgY_orig, 0x103
+	nop.i 999 
+}
+{ .mfi
+	nop.m 999
+//
+//
+//  Save original input args and load table ptr.
+//
+(p0)   fclass.m.unc p6,p0 = ArgX_orig, 0x103
+	nop.i 999
+};;
+{ .mfi
+(p0)   addl      table_ptr1   = @ltoff(Constants_atan#), gp
+(p0)   fclass.m.unc p0,p9 = ArgY_orig, 0x1FF
+	nop.i 999 ;;
+}
+{ .mfi
+       ld8 table_ptr1 = [table_ptr1]
+(p0)   fclass.m.unc p0,p8 = ArgX_orig, 0x1FF
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fclass.m.unc p13,p0 = ArgY_orig, 0x0C3
+	nop.i 999 ;;
+}
+{ .mfi
+(p0)   fclass.m.unc p12,p0 = ArgX_orig, 0x0C3
+	nop.i 999
+}
+
+
+//
+//     Check for NatVals.
+//     Check for everything - if false, then must be pseudo-zero
+//     or pseudo-nan (IA unsupporteds).
+//
+{ .mib
+	nop.m 999
+	nop.i 999
+(p6)   br.cond.spnt L(ATANL_NATVAL) ;;
+}
+
+{ .mib
+	nop.m 999
+	nop.i 999
+(p7)   br.cond.spnt L(ATANL_NATVAL) ;;
+}
+{ .mib
+(p0)   ldfd P_hi = [table_ptr1],8
+	nop.i 999
+(p8)   br.cond.spnt L(ATANL_UNSUPPORTED) ;;
+}
+{ .mbb
+(p0)   add table_ptr2 = 96, table_ptr1
+(p9)   br.cond.spnt L(ATANL_UNSUPPORTED)
+//
+//     Load double precision high-order part of pi
+//
+(p12)  br.cond.spnt L(ATANL_NAN) ;;
+}
+{ .mfb
+	nop.m 999
+(p0)   fnorm.s1 ArgX = ArgX
+(p13)  br.cond.spnt L(ATANL_NAN) ;;
+}
+//
+//     Normalize the input argument.
+//     Branch out if NaN inputs
+//
+{ .mmf
+(p0)   ldfs P_lo = [table_ptr1], 4
+	nop.m 999
+(p0)   fnorm.s1 ArgY = ArgY ;;
+}
+{ .mmf
+	nop.m 999
+(p0)   ldfs TWO_TO_NEG3 = [table_ptr1], 180
+//
+//     U = max(ArgX_abs,ArgY_abs)
+//     V = min(ArgX_abs,ArgY_abs)
+//     if PR1, swap = 0
+//     if PR2, swap = 1
+//
+(p0)   mov M = f1 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Get exp and sign of ArgX
+//     Get exp and sign of ArgY
+//     Load 2**(-3) and increment ptr to Q_4.
+//
+(p0)   fmerge.s ArgX_abs = f1, ArgX
+	nop.i 999 ;;
+}
+//
+//     load single precision low-order part of pi = P_lo
+//
+{ .mfi
+(p0)   getf.exp sign_X = ArgX
+(p0)   fmerge.s ArgY_abs = f1, ArgY
+	nop.i 999 ;;
+}
+{ .mii
+(p0)   getf.exp sign_Y = ArgY
+	nop.i 999 ;;
+(p0)   shr sign_X = sign_X, 17 ;;
+}
+{ .mii
+	nop.m 999
+(p0)   shr sign_Y = sign_Y, 17 ;;
+(p0)   cmp.eq.unc p8, p9 = 0x00000, sign_Y ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Is ArgX_abs >= ArgY_abs
+//     Is sign_Y == 0?
+//
+(p0)   fmax.s1 U = ArgX_abs, ArgY_abs
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+//
+//     ArgX_abs = |ArgX|
+//     ArgY_abs = |ArgY|
+//     sign_X is sign bit of ArgX
+//     sign_Y is sign bit of ArgY
+//
+(p0)   fcmp.ge.s1 p6, p7 = ArgX_abs, ArgY_abs
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fmin.s1 V = ArgX_abs, ArgY_abs
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p8)   fadd.s1 s_Y = f0, f1
+(p6)   cmp.eq.unc p10, p11 = 0x00000, sign_X
+}
+{ .mii
+(p6)   add swap = r0, r0
+	nop.i 999 ;;
+(p7)   add swap = 1, r0
+}
+{ .mfi
+	nop.m 999
+//
+//     Let M = 1.0
+//     if p8, s_Y = 1.0
+//     if p9, s_Y = -1.0
+//
+(p10)  fsub.s1 M = M, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p9)   fsub.s1 s_Y = f0, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   frcpa.s1 E, p6 = V, U
+	nop.i 999 ;;
+}
+{ .mbb
+	nop.m 999
+//
+//     E = frcpa(V,U)
+//
+(p6)   br.cond.sptk L(ATANL_STEP2)
+(p0)   br.cond.spnt L(ATANL_SPECIAL_HANDLING) ;;
+}
+L(ATANL_STEP2): 
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 Q = E, V
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fcmp.eq.s0     p0, p9 = f1, ArgY_orig
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Is Q < 2**(-3)?
+//
+(p0)   fcmp.eq.s0     p0, p8 = f1, ArgX_orig
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p11)  fadd.s1 M = M, f1
+	nop.i 999 ;;
+}
+{ .mlx
+	nop.m 999
+// *************************************************
+// ********************* STEP2 *********************
+// *************************************************
+(p0)   movl special = 0x8400000000000000
+}
+{ .mlx
+	nop.m 999
+//
+//     lookup = b_1 b_2 b_3 B_4
+//
+(p0)   movl special1 = 0x0000000000000100 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Do fnorms to raise any denormal operand
+//     exceptions.
+//
+(p0)   fmpy.s1 P_hi = M, P_hi
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 P_lo = M, P_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Q = E * V
+//
+(p0)   fcmp.lt.unc.s1 p6, p7 = Q, TWO_TO_NEG3
+	nop.i 999 ;;
+}
+{ .mmb
+(p0)   getf.sig significand_Q = Q
+(p0)   getf.exp exponent_Q =  Q
+	nop.b 999 ;;
+}
+{ .mmi
+	nop.m 999 ;;
+(p0)   andcm k = 0x0003, exponent_Q
+(p0)   extr.u lookup = significand_Q, 59, 4 ;;
+}
+{ .mib
+	nop.m 999
+(p0)   dep special = lookup, special, 59, 4
+//
+//     Generate 1.b_1 b_2 b_3 b_4 1 0 0 0 ... 0
+//
+(p6)   br.cond.spnt L(ATANL_POLY) ;;
+}
+{ .mfi
+(p0)   cmp.eq.unc p8, p9 = 0x0000, k
+(p0)   fmpy.s1 P_hi = s_Y, P_hi
+//
+//     We waited a few extra cycles so P_lo and P_hi could be calculated.
+//     Load the constant 256 for loading up table entries.
+//
+// *************************************************
+// ******************** STEP3 **********************
+// *************************************************
+(p0)   add table_ptr2 = 16, table_ptr1
+}
+//
+//     Let z_hi have exponent and sign of original Q
+//     Load the Tbl_hi(0) else, increment pointer.
+//
+{ .mii
+(p0)   ldfe Q_4 = [table_ptr1], -16
+(p0)   xor swap = sign_X, swap ;;
+(p9)   sub k = k, r0, 1
+}
+{ .mmi
+(p0)   setf.sig z_hi = special
+(p0)   ldfe Q_3 = [table_ptr1], -16
+(p9)   add table_ptr2 = 16, table_ptr2 ;;
+}
+//
+//     U_hold = U - U_prime_hi
+//     k = k * 256 - Result can be 0, 256, or 512.
+//
+{ .mmb
+(p0)   ldfe Q_2 = [table_ptr1], -16
+(p8)   ldfd Tbl_hi = [table_ptr2], 8
+	nop.b 999 ;;
+}
+//
+//     U_prime_lo =  U_hold + V * z_hi
+//     lookup -> lookup * 16 + k
+//
+{ .mmi
+(p0)   ldfe Q_1 = [table_ptr1], -16 ;;
+(p8)   ldfs Tbl_lo = [table_ptr2], 8
+//
+//     U_prime_hi = U + V * z_hi
+//     Load the Tbl_lo(0)
+//
+(p9)   pmpy2.r k = k, special1 ;;
+}
+{ .mii
+	nop.m 999
+	nop.i 999 
+	nop.i 999 ;;
+}
+{ .mii
+	nop.m 999
+	nop.i 999 
+	nop.i 999 ;;
+}
+{ .mii
+	nop.m 999
+	nop.i 999 
+	nop.i 999 ;;
+}
+{ .mii
+	nop.m 999
+	nop.i 999 ;;
+(p9)   shladd lookup = lookup, 0x0004, k ;;
+}
+{ .mmi
+(p9)   add table_ptr2 = table_ptr2, lookup ;;
+//
+//     V_prime =  V - U * z_hi
+//
+(p9)   ldfd Tbl_hi = [table_ptr2], 8
+	nop.i 999 ;;
+}
+{ .mmf
+	nop.m 999
+//
+//     C_hi = frcpa(1,U_prime_hi)
+//
+(p9)   ldfs Tbl_lo = [table_ptr2], 8
+//
+//     z_hi = s exp 1.b_1 b_2 b_3 b_4 1 0 0 0 ... 0
+//     Point to beginning of Tbl_hi entries - k = 0.
+//
+(p0)   fmerge.se z_hi = Q, z_hi ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 U_prime_hi = V, z_hi, U
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fnma.s1 V_prime = U, z_hi, V
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   mov A_hi = Tbl_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fsub.s1 U_hold = U, U_prime_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   frcpa.s1 C_hi, p6 = f1, U_prime_hi
+	nop.i 999 ;;
+}
+{ .mfi
+(p0)   cmp.eq.unc p7, p6 = 0x00000, swap
+(p0)   fmpy.s1 A_hi = s_Y, A_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly = wsq * poly
+//
+(p7)   fadd.s1 sigma = f0, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 U_prime_lo = z_hi, V, U_hold
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p6)   fsub.s1 sigma = f0, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fnma.s1 C_hi_hold = C_hi, U_prime_hi, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     A_lo = A_lo + w_hi
+//     A_hi = s_Y * A_hi
+//
+(p0)   fma.s1 Res_hi = sigma, A_hi, P_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi_hold = 1 - C_hi * U_prime_hi (1)
+//
+(p0)   fma.s1 C_hi = C_hi_hold, C_hi, C_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi = C_hi + C_hi * C_hi_hold    (1)
+//
+(p0)   fnma.s1 C_hi_hold = C_hi, U_prime_hi, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi_hold = 1 - C_hi * U_prime_hi (2)
+//
+(p0)   fma.s1 C_hi = C_hi_hold, C_hi, C_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi = C_hi + C_hi * C_hi_hold    (2)
+//
+(p0)   fnma.s1 C_hi_hold = C_hi, U_prime_hi, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi_hold = 1 - C_hi * U_prime_hi (3)
+//
+(p0)   fma.s1 C_hi = C_hi_hold, C_hi, C_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     C_hi = C_hi + C_hi * C_hi_hold    (3)
+//
+(p0)   fmpy.s1 w_hi = V_prime, C_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     w_hi = V_prime * C_hi
+//
+(p0)   fmpy.s1 wsq = w_hi, w_hi
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fnma.s1 w_lo = w_hi, U_prime_hi, V_prime
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     wsq = w_hi * w_hi
+//     w_lo =  = V_prime - w_hi * U_prime_hi
+//
+(p0)   fma.s1 poly =  wsq, Q_4, Q_3
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fnma.s1 w_lo = w_hi, U_prime_lo, w_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly = Q_3 + wsq * Q_4
+//     w_lo =  = w_lo - w_hi * U_prime_lo
+//
+(p0)   fma.s1 poly = wsq, poly, Q_2
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 w_lo = C_hi, w_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly = Q_2 + wsq * poly
+//     w_lo =  = w_lo * C_hi
+//
+(p0)   fma.s1 poly = wsq, poly, Q_1
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fadd.s1 A_lo = Tbl_lo, w_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Result  =  Res_hi + Res_lo * s_Y  (User Supplied Rounding Mode)
+//
+(p0)   fmpy.s0 Q_1 =  Q_1, Q_1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly = Q_1 + wsq * poly
+//     A_lo = Tbl_lo + w_lo
+//     swap = xor(swap,sign_X)
+//
+(p0)   fmpy.s1 poly = wsq, poly
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Is (swap) != 0 ?
+//     poly = wsq * poly
+//     A_hi = Tbl_hi
+//
+(p0)   fmpy.s1 poly = w_hi, poly
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     if (PR_1) sigma = -1.0
+//     if (PR_2) sigma =  1.0
+//
+(p0)   fadd.s1 A_lo = A_lo, poly
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     P_hi = s_Y * P_hi
+//     A_lo = A_lo + poly
+//
+(p0)   fadd.s1 A_lo = A_lo, w_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 Res_lo = sigma, A_lo, P_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+//
+//     Res_hi = P_hi + sigma * A_hi
+//     Res_lo = P_lo + sigma * A_lo
+//
+(p0)   fma.s0 Result = Res_lo, s_Y, Res_hi
+//
+//     Raise inexact.
+//
+br.ret.sptk   b0 ;;
+}
+//
+//     poly1 = P_5 + zsq * poly1
+//     poly2 = zsq * poly2
+//
+L(ATANL_POLY): 
+{ .mmf
+(p0)   xor swap = sign_X, swap
+	nop.m 999
+(p0)   fnma.s1 E_hold = E, U, f1 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   mov A_temp = Q
+//
+//     poly1 = P_4 + zsq * poly1
+//     swap = xor(swap,sign_X)
+//
+//     sign_X            gr_002
+//     swap              gr_004
+//     poly1 = poly1 <== Done with poly1
+//     poly1 = P_4 + zsq * poly1
+//     swap = xor(swap,sign_X)
+//
+(p0)   cmp.eq.unc p7, p6 = 0x00000, swap
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 P_hi = s_Y, P_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)   fsub.s1 sigma = f0, f1
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p7)   fadd.s1 sigma = f0, f1
+	nop.i 999 ;;
+}
+
+// ***********************************************
+// ******************** STEP4 ********************
+// ***********************************************
+
+{ .mmi
+      nop.m 999
+(p0)  addl           table_ptr1   = @ltoff(Constants_atan#), gp
+      nop.i 999
+}
+;;
+
+{ .mmi
+      ld8 table_ptr1 = [table_ptr1]
+      nop.m 999
+      nop.i 999
+}
+;;
+
+
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 E = E, E_hold, E
+//
+//     Following:
+//     Iterate 3 times E = E + E*(1.0 - E*U)
+//     Also load P_8, P_7, P_6, P_5, P_4
+//     E_hold = 1.0 - E * U     (1)
+//     A_temp = Q
+//
+(p0)   add table_ptr1 = 128, table_ptr1 ;;
+}
+{ .mmf
+	nop.m 999
+//
+//     E = E + E_hold*E         (1)
+//     Point to P_8.
+//
+(p0)   ldfe P_8 = [table_ptr1], -16
+//
+//     poly = z8*poly1 + poly2  (Typo in writeup)
+//     Is (swap) != 0 ?
+//
+(p0)   fnma.s1 z_lo = A_temp, U, V ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     E_hold = 1.0 - E * U     (2)
+//
+(p0)   ldfe P_7 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     E = E + E_hold*E         (2)
+//
+(p0)   ldfe P_6 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     E_hold = 1.0 - E * U     (3)
+//
+(p0)   ldfe P_5 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mmf
+	nop.m 999
+//
+//     E = E + E_hold*E         (3)
+//
+//
+// At this point E approximates 1/U to roughly working precision
+// z = V*E approximates V/U
+//
+(p0)   ldfe P_4 = [table_ptr1], -16
+(p0)   fnma.s1 E_hold = E, U, f1 ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     Z =   V * E
+//
+(p0)   ldfe P_3 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     zsq = Z * Z
+//
+(p0)   ldfe P_2 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mmb
+	nop.m 999
+//
+//     z8 = zsq * zsq
+//
+(p0)   ldfe P_1 = [table_ptr1], -16
+	nop.b 999 ;;
+}
+{ .mlx
+	nop.m 999
+(p0)   movl         int_temp = 0x24005
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 E = E, E_hold, E
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fnma.s1 E_hold = E, U, f1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 E = E, E_hold, E
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 Z = V, E
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+//
+//     z_lo = V - A_temp * U
+//     if (PR_2) sigma =  1.0
+//
+(p0)   fmpy.s1 z_lo = z_lo, E
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 zsq = Z, Z
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+//
+//     z_lo = z_lo * E
+//     if (PR_1) sigma = -1.0
+//
+(p0)   fadd.s1 A_hi = A_temp, z_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     z8 = z8 * z8
+//
+//
+//     Now what we want to do is
+//     poly1 = P_4 + zsq*(P_5 + zsq*(P_6 + zsq*(P_7 + zsq*P_8)))
+//     poly2 = zsq*(P_1 + zsq*(P_2 + zsq*P_3))
+//
+(p0)   fma.s1 poly1 = zsq, P_8, P_7
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 poly2 = zsq, P_3, P_2
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 z8 = zsq, zsq
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fsub.s1 A_temp = A_temp, A_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     A_lo = Z * poly + z_lo
+//
+(p0)   fmerge.s     tmp = A_hi, A_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly1 = P_7 + zsq * P_8
+//     poly2 = P_2 + zsq * P_3
+//
+(p0)   fma.s1 poly1 = zsq, poly1, P_6
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 poly2 = zsq, poly2, P_1
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 z8 = z8, z8
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fadd.s1 z_lo = A_temp, z_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     poly1 = P_6 + zsq * poly1
+//     poly2 = P_2 + zsq * poly2
+//
+(p0)   fma.s1 poly1 = zsq, poly1, P_5
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 poly2 = poly2, zsq
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Result  =  Res_hi + Res_lo  (User Supplied Rounding Mode)
+//
+(p0)   fmpy.s1 P_5 = P_5, P_5
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 poly1 = zsq, poly1, P_4
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 poly = z8, poly1, poly2
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Fixup added to force inexact later -
+//     A_hi = A_temp + z_lo
+//     z_lo = (A_temp - A_hi) + z_lo
+//
+(p0)   fma.s1 A_lo = Z, poly, z_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fadd.s1      A_hi = tmp, A_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fsub.s1      tmp = tmp, A_hi
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fmpy.s1 A_hi = s_Y, A_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fadd.s1      A_lo = tmp, A_lo
+	nop.i 999
+}
+{ .mfi
+(p0)   setf.exp     tmp = int_temp
+//
+//     P_hi = s_Y * P_hi
+//     A_hi = s_Y * A_hi
+//
+(p0)   fma.s1 Res_hi = sigma, A_hi, P_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fclass.m.unc p6,p0 = A_lo, 0x007
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)   mov          A_lo = tmp
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+//
+//     Res_hi = P_hi + sigma * A_hi
+//
+(p0)   fsub.s1 tmp =  P_hi, Res_hi
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     tmp = P_hi - Res_hi
+//
+(p0)   fma.s1 tmp = A_hi, sigma, tmp
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fma.s1 sigma =  A_lo, sigma, P_lo
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     tmp   = sigma * A_hi  + tmp
+//     sigma = A_lo * sigma  + P_lo
+//
+(p0)   fma.s1 Res_lo = s_Y, sigma, tmp
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+//
+//     Res_lo = s_Y * sigma + tmp
+//
+(p0)   fadd.s0 Result = Res_lo, Res_hi
+br.ret.sptk   b0 ;;
+}
+L(ATANL_NATVAL): 
+L(ATANL_UNSUPPORTED): 
+L(ATANL_NAN): 
+{ .mfb
+	nop.m 999
+(p0)   fmpy.s0 Result = ArgX,ArgY 
+(p0)   br.ret.sptk   b0 ;;
+}
+L(ATANL_SPECIAL_HANDLING): 
+{ .mfi
+	nop.m 999
+(p0)   fcmp.eq.s0     p0, p6 = f1, ArgY_orig
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)   fcmp.eq.s0     p0, p5 = f1, ArgX_orig
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)   fclass.m.unc p6, p7 = ArgY, 0x007
+	nop.i 999
+}
+{ .mlx
+	nop.m 999
+(p0)   movl special = 992
+}
+;;
+
+
+{ .mmi
+      nop.m 999
+(p0)  addl           table_ptr1   = @ltoff(Constants_atan#), gp
+      nop.i 999
+}
+;;
+
+{ .mmi
+      ld8 table_ptr1 = [table_ptr1]
+      nop.m 999
+      nop.i 999
+}
+;;
+
+
+{ .mib
+(p0)   add table_ptr1 = table_ptr1, special
+	nop.i 999
+(p7)   br.cond.spnt L(ATANL_ArgY_Not_ZERO) ;;
+}
+{ .mmf
+(p0)   ldfd  Result = [table_ptr1], 8
+	nop.m 999
+(p6)   fclass.m.unc p14, p0 = ArgX, 0x035 ;;
+}
+{ .mmf
+	nop.m 999
+(p0)   ldfd  Result_lo = [table_ptr1], -8
+(p6)   fclass.m.unc p15, p0 = ArgX, 0x036 ;;
+}
+{ .mfi
+	nop.m 999
+(p14)  fmerge.s Result = ArgY, f0
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p6)   fclass.m.unc p13, p0 = ArgX, 0x007
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p14)  fmerge.s Result_lo = ArgY, f0
+	nop.i 999 ;;
+}
+{ .mfi
+(p13)  mov GR_Parameter_TAG = 36 
+	nop.f 999
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//     Return sign_Y * 0 when  ArgX > +0
+//
+(p15)  fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p15)  fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+//
+//     Return sign_Y * 0 when  ArgX < -0
+//
+(p0)   fadd.s0 Result = Result, Result_lo
+(p13)  br.cond.spnt __libm_error_region ;;
+}
+{ .mib
+	nop.m 999
+	nop.i 999
+//
+//     Call error support funciton for atan(0,0)
+//
+(p0)    br.ret.sptk   b0 ;;
+}
+L(ATANL_ArgY_Not_ZERO): 
+{ .mfi
+	nop.m 999
+(p0)   fclass.m.unc p9, p10 = ArgY, 0x023
+	nop.i 999 ;;
+}
+{ .mib
+	nop.m 999
+	nop.i 999
+(p10)  br.cond.spnt  L(ATANL_ArgY_Not_INF) ;;
+}
+{ .mfi
+	nop.m 999
+(p9)   fclass.m.unc p6, p0 = ArgX, 0x017
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p9)   fclass.m.unc p7, p0 = ArgX, 0x021
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p9)   fclass.m.unc p8, p0 = ArgX, 0x022
+	nop.i 999 ;;
+}
+{ .mmi
+(p6)   add table_ptr1 =  16, table_ptr1 ;;
+(p0)   ldfd Result = [table_ptr1], 8
+	nop.i 999 ;;
+}
+{ .mfi
+(p0)   ldfd Result_lo = [table_ptr1], -8
+	nop.f 999
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)   fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)   fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p6)    fadd.s0 Result = Result, Result_lo
+(p6)    br.ret.sptk   b0 ;;
+}
+//
+//     Load PI/2 and adjust its sign.
+//     Return +PI/2 when ArgY = +Inf and ArgX = +/-0 or normal
+//     Return -PI/2 when ArgY = -Inf and ArgX = +/-0 or normal
+//
+{ .mmi
+(p7)   add table_ptr1 = 32, table_ptr1 ;;
+(p7)   ldfd Result = [table_ptr1], 8
+	nop.i 999 ;;
+}
+{ .mfi
+(p7)   ldfd Result_lo = [table_ptr1], -8
+	nop.f 999
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p7)   fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p7)   fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p7)    fadd.s0 Result = Result, Result_lo
+(p7)    br.ret.sptk   b0 ;;
+}
+//
+//     Load PI/4 and adjust its sign.
+//     Return +PI/4 when ArgY = +Inf and ArgX = +Inf
+//     Return -PI/4 when ArgY = -Inf and ArgX = +Inf
+//
+{ .mmi
+(p8)   add table_ptr1 = 48, table_ptr1 ;;
+(p8)   ldfd Result = [table_ptr1], 8
+	nop.i 999 ;;
+}
+{ .mfi
+(p8)   ldfd Result_lo = [table_ptr1], -8
+	nop.f 999
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p8)   fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p8)   fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p8)   fadd.s0 Result = Result, Result_lo
+(p8)   br.ret.sptk   b0 ;; 
+}
+L(ATANL_ArgY_Not_INF): 
+{ .mfi
+	nop.m 999
+//
+//     Load PI/4 and adjust its sign.
+//     Return +3PI/4 when ArgY = +Inf and ArgX = -Inf
+//     Return -3PI/4 when ArgY = -Inf and ArgX = -Inf
+//
+(p0)  fclass.m.unc p6, p0 = ArgX, 0x007
+	nop.i 999
+}
+{ .mfi
+	nop.m 999
+(p0)  fclass.m.unc p7, p0 = ArgX, 0x021
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p0)  fclass.m.unc p8, p0 = ArgX, 0x022
+	nop.i 999 ;;
+}
+{ .mmi
+(p6)  add table_ptr1 = 16, table_ptr1 ;;
+(p6)  ldfd Result = [table_ptr1], 8
+	nop.i 999 ;;
+}
+{ .mfi
+(p6)  ldfd Result_lo = [table_ptr1], -8
+	nop.f 999
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)  fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p6)  fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p6)  fadd.s0 Result = Result, Result_lo
+(p6)  br.ret.spnt   b0 ;;
+}
+{ .mfi
+	nop.m 999
+//
+//    return = sign_Y * PI/2 when ArgX = 0
+//
+(p7)  fmerge.s Result = ArgY, f0
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p7)  fnorm.s0 Result = Result
+(p7)  br.ret.spnt   b0 ;;
+}
+//
+//    return = sign_Y * 0 when ArgX = Inf
+//
+{ .mmi
+(p8)  ldfd Result = [table_ptr1], 8 ;;
+(p8)  ldfd Result_lo = [table_ptr1], -8
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p8)  fmerge.s Result = ArgY, Result
+	nop.i 999 ;;
+}
+{ .mfi
+	nop.m 999
+(p8)  fmerge.s Result_lo = ArgY, Result_lo
+	nop.i 999 ;;
+}
+{ .mfb
+	nop.m 999
+(p8)  fadd.s0 Result = Result, Result_lo
+(p8)  br.ret.sptk   b0 ;;
+}
+//
+//    return = sign_Y * PI when ArgX = -Inf
+//
+.endp atan2l
+ASM_SIZE_DIRECTIVE(atan2l)
+ASM_SIZE_DIRECTIVE(__atan2l)
+ASM_SIZE_DIRECTIVE(__ieee754_atan2l)
+ 
+.proc __libm_error_region
+__libm_error_region:
+.prologue
+{ .mfi
+        add   GR_Parameter_Y=-32,sp             // Parameter 2 value
+        nop.f 0
+.save   ar.pfs,GR_SAVE_PFS
+        mov  GR_SAVE_PFS=ar.pfs                 // Save ar.pfs
+}
+{ .mfi
+.fframe 64
+        add sp=-64,sp                           // Create new stack
+        nop.f 0
+        mov GR_SAVE_GP=gp                       // Save gp
+};;
+{ .mmi
+        stfe [GR_Parameter_Y] = FR_Y,16         // Save Parameter 2 on stack
+        add GR_Parameter_X = 16,sp              // Parameter 1 address
+.save   b0, GR_SAVE_B0
+        mov GR_SAVE_B0=b0                       // Save b0
+};;
+.body
+{ .mib
+        stfe [GR_Parameter_X] = FR_X            // Store Parameter 1 on stack
+        add   GR_Parameter_RESULT = 0,GR_Parameter_Y
+        nop.b 0                                 // Parameter 3 address
+}
+{ .mib
+        stfe [GR_Parameter_Y] = FR_RESULT      // Store Parameter 3 on stack
+        add   GR_Parameter_Y = -16,GR_Parameter_Y
+        br.call.sptk b0=__libm_error_support#  // Call error handling function
+};;
+{ .mmi
+        nop.m 0
+        nop.m 0
+        add   GR_Parameter_RESULT = 48,sp
+};;
+{ .mmi
+        ldfe  f8 = [GR_Parameter_RESULT]       // Get return result off stack
+.restore sp
+        add   sp = 64,sp                       // Restore stack pointer
+        mov   b0 = GR_SAVE_B0                  // Restore return address
+};;
+{ .mib
+        mov   gp = GR_SAVE_GP                  // Restore gp
+        mov   ar.pfs = GR_SAVE_PFS             // Restore ar.pfs
+        br.ret.sptk     b0                     // Return
+};;
+
+.endp __libm_error_region
+ASM_SIZE_DIRECTIVE(__libm_error_region) 
+.type   __libm_error_support#,@function
+.global __libm_error_support#