summaryrefslogtreecommitdiff
path: root/ports/sysdeps/ia64/fpu/s_atan.S
diff options
context:
space:
mode:
Diffstat (limited to 'ports/sysdeps/ia64/fpu/s_atan.S')
-rw-r--r--ports/sysdeps/ia64/fpu/s_atan.S753
1 files changed, 753 insertions, 0 deletions
diff --git a/ports/sysdeps/ia64/fpu/s_atan.S b/ports/sysdeps/ia64/fpu/s_atan.S
new file mode 100644
index 0000000000..720ecad28a
--- /dev/null
+++ b/ports/sysdeps/ia64/fpu/s_atan.S
@@ -0,0 +1,753 @@
+.file "atan.s"
+
+
+// Copyright (c) 2000 - 2003, Intel Corporation
+// All rights reserved.
+//
+// Contributed 2000 by the Intel Numerics Group, Intel Corporation
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//
+// * Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// * The name of Intel Corporation may not be used to endorse or promote
+// products derived from this software without specific prior written
+// permission.
+
+// 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://www.intel.com/software/products/opensource/libraries/num.htm.
+//
+// History
+//==============================================================
+// 02/02/00 Initial version
+// 04/13/00 Improved speed
+// 04/19/00 Removed the qualifying predicate from the fmerge.s that
+// takes the absolute value.
+// 06/16/00 Reassigned FP registers to eliminate stalls on loads
+// 08/30/00 Saved 5 cycles in main path by rearranging large argument logic
+// and delaying use of result of fcmp in load by 1 group
+// 05/20/02 Cleaned up namespace and sf0 syntax
+// 08/20/02 Use atan2 algorithm with x=1 for better accuracy
+// 02/06/03 Reordered header: .section, .global, .proc, .align
+//
+// API
+//==============================================================
+// double atan(double Y)
+//
+// Overview of operation
+//==============================================================
+//
+// The atan function returns values in the interval [-pi/2,+pi/2].
+//
+// The algorithm used is the atan2(Y,X) algorithm where we fix X=1.0.
+//
+// There are two basic paths: swap true and swap false.
+// atan2(Y,X) ==> atan2(V/U) where U >= V. If Y > X, we must swap.
+//
+// p6 swap True |Y| > |X|
+// p7 swap False |Y| <= |X|
+//
+//
+// Simple trigonometric identities show
+// Region 1
+// |Y|<=1.0, V=Y, U=1.0 atan2(Y,X) = sgnY * (0 + atan(V/U))
+//
+// Region 2
+// |Y|>1.0, V=1.0, U=Y atan2(Y,X) = sgnY * (pi/2 - atan(V/U))
+//
+//
+// We compute atan(V/U) from the identity
+// atan(z) + atan([(V/U)-z] / [1+(V/U)z])
+// where z is a limited precision approximation (16 bits) to V/U
+//
+// z is calculated with the assistance of the frcpa instruction.
+//
+// atan(z) is calculated by a polynomial z + z^3 * p(w), w=z^2
+// where p(w) = P0+P1*w+...+P22*w^22
+//
+// Let d = [(V/U)-z] / [1+(V/U)z]) = (V-U*z)/(U+V*z)
+//
+// Approximate atan(d) by d + P0*d^3
+// Let F = 1/(U+V*z) * (1-a), where |a|< 2^-8.8.
+// Compute q(a) = 1 + a + ... + a^5.
+// Then F*q(a) approximates the reciprocal to more than 50 bits.
+
+// Special values
+//==============================================================
+// atan(QNAN) = QNAN
+// atan(SNAN) = quieted SNAN
+// atan(+-inf) = +- pi/2
+// atan(+-0) = +-0
+
+// Registers used
+//==============================================================
+
+// predicate registers used:
+// p6 -> p15
+
+// floating-point registers used:
+// f8, input
+// f32 -> f116
+
+// general registers used
+// r14 -> r16
+
+// Assembly macros
+//==============================================================
+
+EXP_AD_P1 = r14
+EXP_AD_P2 = r15
+rsig_near_one = r16
+
+atan2_Y = f8
+atan2_X = f1
+
+atan2_u1_X = f32
+atan2_u1_Y = f33
+atan2_z2_X = f34
+
+atan2_two = f36
+atan2_B1sq_Y = f37
+atan2_z1_X = f38
+atan2_B1X = f40
+
+atan2_B1Y = f41
+atan2_wp_X = f42
+atan2_B1sq_X = f43
+atan2_z = f44
+atan2_w = f45
+
+atan2_P0 = f46
+atan2_P1 = f47
+atan2_P2 = f48
+atan2_P3 = f49
+atan2_P4 = f50
+
+atan2_P5 = f51
+atan2_P6 = f52
+atan2_P7 = f53
+atan2_P8 = f54
+atan2_P9 = f55
+
+atan2_P10 = f56
+atan2_P11 = f57
+atan2_P12 = f58
+atan2_P13 = f59
+atan2_P14 = f60
+
+atan2_P15 = f61
+atan2_P16 = f62
+atan2_P17 = f63
+atan2_P18 = f64
+atan2_P19 = f65
+
+atan2_P20 = f66
+atan2_P21 = f67
+atan2_P22 = f68
+atan2_pi_by_2 = f69
+atan2_sgn_pi_by_2 = f69
+atan2_V13 = f70
+
+atan2_W11 = f71
+atan2_E = f72
+atan2_wp_Y = f73
+atan2_V11 = f74
+atan2_V12 = f75
+
+atan2_V7 = f76
+atan2_V8 = f77
+atan2_W7 = f78
+atan2_W8 = f79
+atan2_W3 = f80
+
+atan2_W4 = f81
+atan2_V3 = f82
+atan2_V4 = f83
+atan2_F = f84
+atan2_gV = f85
+
+atan2_V10 = f86
+atan2_zcub = f87
+atan2_V6 = f88
+atan2_V9 = f89
+atan2_W10 = f90
+
+atan2_W6 = f91
+atan2_W2 = f92
+atan2_V2 = f93
+atan2_alpha = f94
+atan2_alpha_1 = f95
+
+atan2_gVF = f96
+atan2_V5 = f97
+atan2_W12 = f98
+atan2_W5 = f99
+atan2_alpha_sq = f100
+
+atan2_Cp = f101
+atan2_V1 = f102
+atan2_ysq = f103
+atan2_W1 = f104
+atan2_alpha_cub = f105
+
+atan2_C = f106
+atan2_d = f108
+atan2_A_hi = f109
+atan2_dsq = f110
+
+atan2_pd = f111
+atan2_A_lo = f112
+atan2_A = f113
+atan2_Pp = f114
+atan2_sgnY = f115
+
+atan2_sig_near_one = f116
+atan2_near_one = f116
+
+/////////////////////////////////////////////////////////////
+
+
+RODATA
+
+.align 16
+
+LOCAL_OBJECT_START(atan2_tb1)
+data8 0xA21922DC45605EA1 , 0x00003FFA // P11
+data8 0xB199DD6D2675C40F , 0x0000BFFA // P10
+data8 0xC2F01E5DDD100DBE , 0x00003FFA // P9
+data8 0xD78F28FC2A592781 , 0x0000BFFA // P8
+data8 0xF0F03ADB3FC930D3 , 0x00003FFA // P7
+data8 0x88887EBB209E3543 , 0x0000BFFB // P6
+data8 0x9D89D7D55C3287A5 , 0x00003FFB // P5
+data8 0xBA2E8B9793955C77 , 0x0000BFFB // P4
+data8 0xE38E38E320A8A098 , 0x00003FFB // P3
+data8 0x9249249247E37913 , 0x0000BFFC // P2
+data8 0xCCCCCCCCCCC906CD , 0x00003FFC // P1
+data8 0xAAAAAAAAAAAAA8A9 , 0x0000BFFD // P0
+data8 0x0000000000000000 , 0x00000000 // pad to avoid bank conflict
+LOCAL_OBJECT_END(atan2_tb1)
+
+LOCAL_OBJECT_START(atan2_tb2)
+data8 0xCE585A259BD8374C , 0x00003FF0 // P21
+data8 0x9F90FB984D8E39D0 , 0x0000BFF3 // P20
+data8 0x9D3436AABE218776 , 0x00003FF5 // P19
+data8 0xDEC343E068A6D2A8 , 0x0000BFF6 // P18
+data8 0xF396268151CFB11C , 0x00003FF7 // P17
+data8 0xD818B4BB43D84BF2 , 0x0000BFF8 // P16
+data8 0xA2270D30A90AA220 , 0x00003FF9 // P15
+data8 0xD5F4F2182E7A8725 , 0x0000BFF9 // P14
+data8 0x80D601879218B53A , 0x00003FFA // P13
+data8 0x9297B23CCFFB291F , 0x0000BFFA // P12
+data8 0xFE7E52D2A89995B3 , 0x0000BFEC // P22
+data8 0xC90FDAA22168C235 , 0x00003FFF // pi/2
+LOCAL_OBJECT_END(atan2_tb2)
+
+
+
+
+.section .text
+GLOBAL_LIBM_ENTRY(atan)
+
+{ .mfi
+ nop.m 999
+ frcpa.s1 atan2_u1_Y,p7 = f1,atan2_Y
+ nop.i 999
+}
+{ .mfi
+ addl EXP_AD_P1 = @ltoff(atan2_tb1), gp
+ fma.s1 atan2_two = f1,f1,f1
+ nop.i 999
+;;
+}
+
+{ .mfi
+ ld8 EXP_AD_P1 = [EXP_AD_P1]
+ frcpa.s1 atan2_u1_X,p6 = f1,atan2_X
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_ysq = atan2_Y,atan2_Y,f0
+ nop.i 999
+}
+;;
+
+{ .mfi
+ add EXP_AD_P2 = 0xd0,EXP_AD_P1
+ fmerge.s atan2_sgnY = atan2_Y,f1
+ nop.i 999
+}
+;;
+
+
+{ .mfi
+ ldfe atan2_P11 = [EXP_AD_P1],16
+ fclass.m p10,p0 = atan2_Y, 0xc3 // Test for y=nan
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P21 = [EXP_AD_P2],16
+ nop.f 999
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ ldfe atan2_P10 = [EXP_AD_P1],16
+ fnma.s1 atan2_B1Y = atan2_u1_Y, atan2_Y, atan2_two
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P20 = [EXP_AD_P2],16
+ fma.s1 atan2_wp_Y = atan2_u1_Y, atan2_u1_Y, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ ldfe atan2_P9 = [EXP_AD_P1],16
+ fma.s1 atan2_z1_X = atan2_u1_X, atan2_Y, f0
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P19 = [EXP_AD_P2],16
+ fnma.s1 atan2_B1X = atan2_u1_X, atan2_X, atan2_two
+ nop.i 999
+}
+;;
+
+{ .mfi
+ ldfe atan2_P8 = [EXP_AD_P1],16
+ fma.s1 atan2_z2_X = atan2_u1_X, atan2_ysq, f0
+ nop.i 999
+}
+{ .mfb
+ ldfe atan2_P18 = [EXP_AD_P2],16
+(p10) fma.d.s0 f8 = atan2_Y,atan2_X,f0 // If y=nan, result quietized y
+(p10) br.ret.spnt b0 // Exit if y=nan
+}
+;;
+
+// p6 true if swap, means |y| > 1.0 or ysq > 1.0
+// p7 true if no swap, means 1.0 >= |y| or 1.0 >= ysq
+{ .mfi
+ ldfe atan2_P7 = [EXP_AD_P1],16
+ fcmp.ge.s1 p7,p6 = f1, atan2_ysq
+ nop.i 999
+}
+{ .mmf
+ ldfe atan2_P17 = [EXP_AD_P2],16
+ nop.m 999
+ nop.f 999
+}
+;;
+
+{ .mfi
+ ldfe atan2_P6 = [EXP_AD_P1],16
+ fma.s1 atan2_E = atan2_u1_Y, atan2_B1Y, atan2_Y
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P16 = [EXP_AD_P2],16
+ fma.s1 atan2_B1sq_Y = atan2_B1Y, atan2_B1Y, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ ldfe atan2_P5 = [EXP_AD_P1],16
+(p7) fma.s1 atan2_wp_X = atan2_z1_X, atan2_z1_X, f0
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P15 = [EXP_AD_P2],16
+(p7) fma.s1 atan2_B1sq_X = atan2_B1X, atan2_B1X, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ ldfe atan2_P4 = [EXP_AD_P1],16
+(p6) fma.s1 atan2_z = atan2_u1_Y, atan2_B1Y, f0
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P14 = [EXP_AD_P2],16
+(p7) fma.s1 atan2_E = atan2_z2_X, atan2_B1X, atan2_X
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ ldfe atan2_P3 = [EXP_AD_P1],16
+ fcmp.eq.s0 p14,p15=atan2_X,atan2_Y // Dummy for denorm and invalid
+ nop.i 999
+}
+{ .mmf
+ ldfe atan2_P13 = [EXP_AD_P2],16
+ nop.m 999
+(p7) fma.s1 atan2_z = atan2_z1_X, atan2_B1X, f0
+;;
+}
+
+{ .mfi
+ ldfe atan2_P2 = [EXP_AD_P1],16
+(p6) fma.s1 atan2_w = atan2_wp_Y, atan2_B1sq_Y,f0
+ nop.i 999
+}
+{ .mlx
+ ldfe atan2_P12 = [EXP_AD_P2],16
+ movl rsig_near_one = 0x8000000000000001 // signif near 1.0
+;;
+}
+
+{ .mfi
+ ldfe atan2_P1 = [EXP_AD_P1],16
+ fclass.m p9,p0 = atan2_Y, 0x23 // test if y inf
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_P22 = [EXP_AD_P2],16
+(p7) fma.s1 atan2_w = atan2_wp_X, atan2_B1sq_X,f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ ldfe atan2_P0 = [EXP_AD_P1],16
+ frcpa.s1 atan2_F,p0 = f1, atan2_E
+ nop.i 999
+}
+{ .mfi
+ ldfe atan2_pi_by_2 = [EXP_AD_P2],16
+(p6) fnma.s1 atan2_gV = atan2_Y, atan2_z, atan2_X
+ nop.i 999
+;;
+}
+
+{ .mfi
+ setf.sig atan2_sig_near_one = rsig_near_one
+(p7) fnma.s1 atan2_gV = atan2_X, atan2_z, atan2_Y
+ nop.i 999
+}
+{ .mfb
+ nop.m 999
+(p9) fma.d.s0 f8 = atan2_sgnY, atan2_pi_by_2, f0 // +-pi/2 if y inf
+(p9) br.ret.spnt b0 // exit if y inf, result is +-pi/2
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V13 = atan2_w, atan2_P11, atan2_P10
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W11 = atan2_w, atan2_P21, atan2_P20
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V11 = atan2_w, atan2_P9, atan2_P8
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V12 = atan2_w, atan2_w, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V8 = atan2_w, atan2_P7 , atan2_P6
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W8 = atan2_w, atan2_P19, atan2_P18
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fnma.s1 atan2_alpha = atan2_E, atan2_F, f1
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fnma.s1 atan2_alpha_1 = atan2_E, atan2_F, atan2_two
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V7 = atan2_w, atan2_P5 , atan2_P4
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W7 = atan2_w, atan2_P17, atan2_P16
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V4 = atan2_w, atan2_P3 , atan2_P2
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W4 = atan2_w, atan2_P15, atan2_P14
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V3 = atan2_w, atan2_P1 , atan2_P0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W3 = atan2_w, atan2_P13, atan2_P12
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V10 = atan2_V12, atan2_V13, atan2_V11
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_gVF = atan2_gV, atan2_F, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_alpha_sq = atan2_alpha, atan2_alpha, f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_Cp = atan2_alpha, atan2_alpha_1, f1
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V9 = atan2_V12, atan2_V12, f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W10 = atan2_V12, atan2_P22 , atan2_W11
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V6 = atan2_V12, atan2_V8 , atan2_V7
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W6 = atan2_V12, atan2_W8 , atan2_W7
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V2 = atan2_V12, atan2_V4 , atan2_V3
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W2 = atan2_V12, atan2_W4 , atan2_W3
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_alpha_cub = atan2_alpha, atan2_alpha_sq, f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_C = atan2_gVF, atan2_Cp, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W12 = atan2_V9, atan2_V9, f0
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V5 = atan2_V9, atan2_V10, atan2_V6
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W5 = atan2_V9, atan2_W10, atan2_W6
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fclass.m p8,p0 = atan2_Y, 0x07 // Test for y=0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_d = atan2_alpha_cub, atan2_C, atan2_C
+ nop.i 999
+}
+;;
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W12 = atan2_V9, atan2_W12, f0
+ nop.i 999
+}
+;;
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_V1 = atan2_V9, atan2_V5, atan2_V2
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_W1 = atan2_V9, atan2_W5, atan2_W2
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+(p8) fmerge.s f8 = atan2_sgnY, f0 // +-0 if y=0
+ nop.i 999
+}
+{ .mfb
+ nop.m 999
+ fma.s1 atan2_zcub = atan2_z, atan2_w, f0
+(p8) br.ret.spnt b0 // Exit if y=0
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_pd = atan2_P0, atan2_d, f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_dsq = atan2_d, atan2_d, f0
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ nop.m 999
+ fmerge.se atan2_near_one = f1, atan2_sig_near_one // Const ~1.0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_Pp = atan2_W12, atan2_W1, atan2_V1
+ nop.i 999
+;;
+}
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_sgn_pi_by_2 = atan2_pi_by_2, atan2_sgnY, f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_A_lo = atan2_pd, atan2_dsq, atan2_d
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ nop.m 999
+ fma.s1 atan2_A_hi = atan2_zcub, atan2_Pp, atan2_z
+ nop.i 999
+;;
+}
+
+
+{ .mfi
+ nop.m 999
+(p6) fma.s1 atan2_A = atan2_A_hi, f1, atan2_A_lo
+ nop.i 999
+}
+// For |Y| <= |X| and X > 0, result is A_hi + A_lo
+{ .mfi
+ nop.m 999
+(p7) fma.d.s0 f8 = atan2_A_hi, f1, atan2_A_lo
+ nop.i 999
+;;
+}
+
+// For |Y| > |X|, result is +- pi/2 - (A_hi + A_lo)
+// We perturb A by multiplying by 1.0+1ulp as we produce the result
+// in order to get symmetrically rounded results in directed rounding modes.
+// If we don't do this, there are a few cases where the trailing 11 bits of
+// the significand of the result, before converting to double, are zero. These
+// cases do not round symmetrically in round to +infinity or round to -infinity.
+{ .mfb
+ nop.m 999
+(p6) fnma.d.s0 f8 = atan2_A, atan2_near_one, atan2_sgn_pi_by_2
+ br.ret.sptk b0
+;;
+}
+
+GLOBAL_LIBM_END(atan)