.file "atan2f.s" // Copyright (c) 2000, 2001, Intel Corporation // All rights reserved. // // Contributed 6/1/2000 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 //============================================================== // 6/01/00 Initial version // 8/15/00 Bundle added after call to __libm_error_support to properly // set [the previously overwritten] GR_Parameter_RESULT. // 8/17/00 Changed predicate register macro-usage to direct predicate // names due to an assembler bug. // 1/05/01 Fixed flag settings for denormal input. // 1/19/01 Added documentation // 1/30/01 Improved speed // Description //========================================= // The atan2 function computes the principle value of the arc tangent of y/x using // the signs of both arguments to determine the quadrant of the return value. // A domain error may occur if both arguments are zero. // The atan2 function returns the arc tangent of y/x in the range [-pi,+pi] radians. //.. //..Let (v,u) = (y,x) if |y| <= |x|, and (v,u) = (x,y) otherwise. Note that //..v and u can be negative. We state the relationship between atan2(y,x) and //..atan(v/u). //.. //..Let swap = false if v = y, and swap = true if v = x. //..Define C according to the matrix //.. //.. TABLE FOR C //.. x +ve x -ve //.. no swap (swap = false) sgn(y)*0 sgn(y)*pi //.. swap (swap = true ) sgn(y)*pi/2 sgn(y)*pi/2 //.. //.. atan2(y,x) = C + atan(v/u) if no swap //.. atan2(y,x) = C - atan(v/u) if swap //.. //..These relationship is more efficient to compute as we accommodate signs in v and u //..saving the need to obtain the absolute value before computation can proceed. //.. //..Suppose (v,u) = (y,x), we calculate atan(v/u) as follows: //..A = y * frcpa(x) (so A = (y/x)(1 - beta)) //..atan(y/x) = atan(A) + atan( ((y/x)-A))/(1 + (y/x)A) ), the second term is //..a correction. //..atan(A) is approximated by a polynomial //..A + p1 A^3 + p2 A^5 + ... + p10 A^21, //..atan(G) is approximated as follows: //..Let G = (y - Ax)/(x + Ay), atan(G) can be approximated by G + g * p1 //..where g is a limited precision approximation to G via g = (y - Ax)*frcpa(x + Ay). //.. //..Suppose (v,u) = (x,y), we calculate atan(v/u) as follows: //..Z = x * frcpa(y) (so Z = (x/y)(1 - beta)) //..atan(x/y) = atan(Z) + atan( ((x/y)-Z))/(1 + (x/y)Z) ), the second term is //..a correction. //..atan(Z) is approximated by a polynomial //..Z + p1 Z^3 + p2 Z^5 + ... + p10 Z^21, //..atan(T) is approximated as follows: //..Let T = (x - Ay)/(y + Ax), atan(T) can be approximated by T + t * p1 //..where t is a limited precision approximation to T via t = (x - Ay)*frcpa(y + Ax). //.. //.. //..A = y * frcpa(x) //..atan(A) ~=~ A + p1 A^3 + ... + P10 A^21 //.. //..This polynomial is computed as follows: //..Asq = A*A; Acub = A*Asq, A4 = Asq*Asq //..A5 = Asq*Acub, A6 = Asq*A4; A11 = A5 * A6 //.. //..poly_A1 = p9 + Asq*p10, poly_A2 = p7 + Asq*p8, poly_A3 = p5 + Asq*p6 //..poly_A1 = poly_A2 + A4 * poly_A1 //..poly_A1 = poly_A3 + A4 * poly_A1 //.. //..poly_A4 = p1 * A //,,poly_A5 = p3 + Asq * p4, poly_A4 = A + Asq*poly_A4 //..poly_A5 = p2 + Asq * poly_A5 //..poly_A4 = poly_A4 + A5 * poly_A5 //.. //..atan_A = poly_A4 + A11 * poly_A1 //.. //..atan(G) is approximated as follows: //..G_numer = y - A*x, G_denom = x + A*y //..H1 = frcpa(G_denom) //..H_beta = 1 - H1 * G_denom //..H2 = H1 + H1 * H_beta //..H_beta2 = H_beta*H_beta //..H3 = H2 + H2*H_beta2 //..g = H1 * G_numer; gsq = g*g; atan_G = g*p1, atan_G = atan_G*gsq //..atan_G = G_numer*H3 + atan_G //.. //.. //..A = y * frcpa(x) //..atan(A) ~=~ A + p1 A^3 + ... + P10 A^21 //.. //..This polynomial is computed as follows: //..Asq = A*A; Acub = A*Asq, A4 = Asq*Asq //..A5 = Asq*Acub, A6 = Asq*A4; A11 = A5 * A6 //.. //..poly_A1 = p9 + Asq*p10, poly_A2 = p7 + Asq*p8, poly_A3 = p5 + Asq*p6 //..poly_A1 = poly_A2 + A4 * poly_A1 //..poly_A1 = poly_A3 + A4 * poly_A1 //.. //..poly_A4 = p1 * A //,,poly_A5 = p3 + Asq * p4, poly_A4 = A + Asq*poly_A4 //..poly_A5 = p2 + Asq * poly_A5 //..poly_A4 = poly_A4 + A5 * poly_A5 //.. //..atan_A = poly_A4 + A11 * poly_A1 //.. //.. //..==================================================================== //.. COEFFICIENTS USED IN THE COMPUTATION //..==================================================================== //coef_pj, j = 1,2,...,10; atan(A) ~=~ A + p1 A^3 + p2 A^5 + ... + p10 A^21 // // coef_p1 = -.3333332707155439167401311806315789E+00 // coef_p1 in dbl = BFD5 5555 1219 1621 // // coef_p2 = .1999967670926658391827857030875748E+00 // coef_p2 in dbl = 3FC9 997E 7AFB FF4E // // coef_p3 = -.1427989384500152360161563301087296E+00 // coef_p3 in dbl = BFC2 473C 5145 EE38 // // coef_p4 = .1105852823460720770079031213661163E+00 // coef_p4 in dbl = 3FBC 4F51 2B18 65F5 // // coef_p5 = -.8811839915595312348625710228448363E-01 // coef_p5 in dbl = BFB6 8EED 6A8C FA32 // // coef_p6 = .6742329836955067042153645159059714E-01 // coef_p6 in dbl = 3FB1 42A7 3D7C 54E3 // // coef_p7 = -.4468571068774672908561591262231909E-01 // coef_p7 in dbl = BFA6 E10B A401 393F // // coef_p8 = .2252333246746511135532726960586493E-01 // coef_p8 in dbl = 3F97 105B 4160 F86B // // coef_p9 = -.7303884867007574742501716845542314E-02 // coef_p9 in dbl = BF7D EAAD AA33 6451 // // coef_p10 = .1109686868355312093949039454619058E-02 // coef_p10 in dbl = 3F52 2E5D 33BC 9BAA // // Special values //============================================================== // Y x Result // +number +inf +0 // -number +inf -0 // +number -inf +pi // -number -inf -pi // // +inf +number +pi/2 // -inf +number -pi/2 // +inf -number +pi/2 // -inf -number -pi/2 // // +inf +inf +pi/4 // -inf +inf -pi/4 // +inf -inf +3pi/4 // -inf -inf -3pi/4 // // +1 +1 +pi/4 // -1 +1 -pi/4 // +1 -1 +3pi/4 // -1 -1 -3pi/4 // // +number +0 +pi/2 // does not raise DBZ // -number +0 -pi/2 // does not raise DBZ // +number -0 +pi/2 // does not raise DBZ // -number -0 -pi/2 // does not raise DBZ // // +0 +number +0 // -0 +number -0 // +0 -number +pi // -0 -number -pi // // +0 +0 +0 // does not raise invalid // -0 +0 -0 // does not raise invalid // +0 -0 +pi // does not raise invalid // -0 -0 -pi // does not raise invalid // // Nan anything quiet Y // anything NaN quiet X // atan2(+-0/+-0) sets double error tag to 37 // atan2f(+-0/+-0) sets single error tag to 38 // These are domain errors. // // Assembly macros //========================================= // integer registers atan2f_GR_Addr_1 = r33 atan2f_GR_Addr_2 = r34 GR_SAVE_B0 = r35 GR_SAVE_PFS = r36 GR_SAVE_GP = r37 GR_Parameter_X = r38 GR_Parameter_Y = r39 GR_Parameter_RESULT = r40 GR_Parameter_TAG = r41 // floating point registers atan2f_coef_p1 = f32 atan2f_coef_p10 = f33 atan2f_coef_p7 = f34 atan2f_coef_p6 = f35 atan2f_coef_p3 = f36 atan2f_coef_p2 = f37 atan2f_coef_p9 = f38 atan2f_coef_p8 = f39 atan2f_coef_p5 = f40 atan2f_coef_p4 = f41 atan2f_const_piby2 = f42 atan2f_const_pi = f43 atan2f_const_piby4 = f44 atan2f_const_3piby4 = f45 atan2f_xsq = f46 atan2f_ysq = f47 atan2f_xy = f48 atan2f_const_1 = f49 atan2f_sgn_Y = f50 atan2f_Z0 = f51 atan2f_A0 = f52 atan2f_Z = f53 atan2f_A = f54 atan2f_C = f55 atan2f_U = f56 atan2f_Usq = f57 atan2f_U4 = f58 atan2f_U6 = f59 atan2f_U8 = f60 atan2f_poly_u109 = f61 atan2f_poly_u87 = f62 atan2f_poly_u65 = f63 atan2f_poly_u43 = f64 atan2f_poly_u21 = f65 atan2f_poly_u10to7 = f66 atan2f_poly_u6to3 = f67 atan2f_poly_u10to3 = f68 atan2f_poly_u10to0 = f69 atan2f_poly_u210 = f70 atan2f_T_numer = f71 atan2f_T_denom = f72 atan2f_G_numer = f73 atan2f_G_denom = f74 atan2f_p1rnum = f75 atan2f_R_denom = f76 atan2f_R_numer = f77 atan2f_pR = f78 atan2f_pRC = f79 atan2f_pQRC = f80 atan2f_Q1 = f81 atan2f_Q_beta = f82 atan2f_Q2 = f83 atan2f_Q_beta2 = f84 atan2f_Q3 = f85 atan2f_r = f86 atan2f_rsq = f87 atan2f_poly_atan_U = f88 // predicate registers //atan2f_Pred_Swap = p6 // |y| > |x| //atan2f_Pred_noSwap = p7 // |y| <= |x| //atan2f_Pred_Xpos = p8 // x >= 0 //atan2f_Pred_Xneg = p9 // x < 0 .data .align 16 atan2f_coef_table1: data8 0xBFD5555512191621 // p1 data8 0x3F522E5D33BC9BAA // p10 data8 0xBFA6E10BA401393F // p7 data8 0x3FB142A73D7C54E3 // p6 data8 0xBFC2473C5145EE38 // p3 data8 0x3FC9997E7AFBFF4E // p2 atan2f_coef_table2: data8 0xBF7DEAADAA336451 // p9 data8 0x3F97105B4160F86B // p8 data8 0xBFB68EED6A8CFA32 // p5 data8 0x3FBC4F512B1865F5 // p4 data8 0x3ff921fb54442d18 // pi/2 data8 0x400921fb54442d18 // pi data8 0x3fe921fb54442d18 // pi/4 data8 0x4002d97c7f3321d2 // 3pi/4 .global atan2f .text .proc atan2f .align 32 atan2f: { .mfi alloc r32 = ar.pfs,1,5,4,0 frcpa.s1 atan2f_Z0,p0 = f1,f8 // Approx to 1/y nop.i 999 } { .mfi addl atan2f_GR_Addr_1 = @ltoff(atan2f_coef_table1),gp fma.s1 atan2f_xsq = f9,f9,f0 nop.i 999 ;; } { .mfi ld8 atan2f_GR_Addr_1 = [atan2f_GR_Addr_1] frcpa.s1 atan2f_A0,p0 = f1,f9 // Approx to 1/x nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_ysq = f8,f8,f0 nop.i 999 ;; } { .mfi nop.m 999 fcmp.ge.s1 p8,p9 = f9,f0 // Set p8 if x>=0, p9 if x<0 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_xy = f9,f8,f0 nop.i 999 ;; } { .mfi add atan2f_GR_Addr_2 = 0x30, atan2f_GR_Addr_1 fmerge.s atan2f_sgn_Y = f8,f1 nop.i 999 ;; } { .mmf ldfpd atan2f_coef_p1,atan2f_coef_p10 = [atan2f_GR_Addr_1],16 ldfpd atan2f_coef_p9,atan2f_coef_p8 = [atan2f_GR_Addr_2],16 fclass.m p10,p0 = f9,0xe7 // Test x @inf|@snan|@qnan|@zero } ;; { .mfi ldfpd atan2f_coef_p7,atan2f_coef_p6 = [atan2f_GR_Addr_1],16 fma.s1 atan2f_T_denom = atan2f_Z0,atan2f_xsq,f8 nop.i 999 } { .mfi ldfpd atan2f_coef_p5,atan2f_coef_p4 = [atan2f_GR_Addr_2],16 fma.s1 atan2f_Z = atan2f_Z0,f9,f0 nop.i 999 ;; } { .mfi ldfpd atan2f_coef_p3,atan2f_coef_p2 = [atan2f_GR_Addr_1],16 fma.s1 atan2f_G_denom = atan2f_A0,atan2f_ysq,f9 nop.i 999 } { .mfi ldfpd atan2f_const_piby2,atan2f_const_pi = [atan2f_GR_Addr_2],16 fma.s1 atan2f_A = atan2f_A0,f8,f0 nop.i 999 ;; } { .mfi ldfpd atan2f_const_piby4,atan2f_const_3piby4 = [atan2f_GR_Addr_2] fclass.m p11,p0 = f8,0xe7 // Test y @inf|@snan|@qnan|@zero nop.i 999 } { .mfb nop.m 999 fnma.s1 atan2f_T_numer = atan2f_Z0,atan2f_xy,f9 (p10) br.cond.spnt ATAN2F_XY_INF_NAN_ZERO ;; // Branch on x nan,inf,zero } // p6 if |y|>|x|, p7 if |x|>=|y| , use xsq and ysq for test { .mfi nop.m 999 fcmp.gt.s1 p6,p7 = atan2f_ysq,atan2f_xsq nop.i 999 } { .mfb nop.m 999 fnma.s1 atan2f_G_numer = atan2f_A0,atan2f_xy,f8 (p11) br.cond.spnt ATAN2F_XY_INF_NAN_ZERO ;; // Branch on y nan,inf,zero } { .mfi nop.m 999 (p8) fma.s1 atan2f_const_1 = atan2f_sgn_Y,f0,f0 nop.i 999 } { .mfi nop.m 999 (p9) fma.s1 atan2f_const_1 = atan2f_sgn_Y,f1,f0 nop.i 999 ;; } { .mfi nop.m 999 (p6) fnma.s1 atan2f_U = atan2f_Z,f1,f0 nop.i 999 } { .mfi nop.m 999 (p6) fma.s1 atan2f_Usq = atan2f_Z,atan2f_Z,f0 nop.i 999 ;; } { .mfi nop.m 999 (p7) fma.s1 atan2f_U = atan2f_A,f1,f0 nop.i 999 } { .mfi nop.m 999 (p7) fma.s1 atan2f_Usq = atan2f_A,atan2f_A,f0 nop.i 999 ;; } { .mfi nop.m 999 (p6) frcpa.s1 atan2f_Q1,p0 = f1,atan2f_T_denom nop.i 999 } { .mfi nop.m 999 (p6) fma.s1 atan2f_R_denom = atan2f_T_denom,f1,f0 nop.i 999 ;; } { .mfi nop.m 999 (p7) frcpa.s1 atan2f_Q1,p0 = f1,atan2f_G_denom nop.i 999 } { .mfi nop.m 999 (p7) fma.s1 atan2f_R_denom = atan2f_G_denom,f1,f0 nop.i 999 ;; } { .mfi nop.m 999 (p6) fnma.s1 atan2f_R_numer = atan2f_T_numer,f1,f0 nop.i 999 } { .mfi nop.m 999 (p7) fma.s1 atan2f_R_numer = atan2f_G_numer,f1,f0 nop.i 999 ;; } { .mfi nop.m 999 (p6) fnma.s1 atan2f_p1rnum = atan2f_T_numer,atan2f_coef_p1,f0 nop.i 999 ;; } { .mfi nop.m 999 (p7) fma.s1 atan2f_p1rnum = atan2f_G_numer,atan2f_coef_p1,f0 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_U4 = atan2f_Usq,atan2f_Usq,f0 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_poly_u109 = atan2f_Usq,atan2f_coef_p10,atan2f_coef_p9 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u87 = atan2f_Usq,atan2f_coef_p8,atan2f_coef_p7 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_poly_u65 = atan2f_Usq,atan2f_coef_p6,atan2f_coef_p5 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u43 = atan2f_Usq,atan2f_coef_p4,atan2f_coef_p3 nop.i 999 } { .mfi nop.m 999 fnma.s1 atan2f_Q_beta = atan2f_Q1,atan2f_R_denom,f1 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u21 = atan2f_Usq,atan2f_coef_p2,atan2f_coef_p1 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_r = atan2f_Q1,atan2f_R_numer,f0 nop.i 999 ;; } { .mfi nop.m 999 (p6) fma.s1 atan2f_C = atan2f_sgn_Y,atan2f_const_piby2,f0 nop.i 999 } { .mfi nop.m 999 (p7) fma.s1 atan2f_C = atan2f_const_1,atan2f_const_pi,f0 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_U6 = atan2f_U4,atan2f_Usq,f0 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_U8 = atan2f_U4,atan2f_U4,f0 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u10to7 = atan2f_U4,atan2f_poly_u109,atan2f_poly_u87 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_pR = atan2f_p1rnum,atan2f_Q1,f0 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u6to3 = atan2f_U4,atan2f_poly_u65,atan2f_poly_u43 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_Q2 = atan2f_Q1,atan2f_Q_beta,atan2f_Q1 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_Q_beta2 = atan2f_Q_beta,atan2f_Q_beta,f0 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_rsq = atan2f_r,atan2f_r,f0 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u210 = atan2f_Usq,atan2f_poly_u21,f1 nop.i 999 ;; } { .mfi nop.m 999 fcmp.eq.s0 p8,p0 = f8,f9 // Dummy op to set flag on denormal inputs nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_poly_u10to3 = atan2f_U8,atan2f_poly_u10to7,atan2f_poly_u6to3 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_Q3 = atan2f_Q2,atan2f_Q_beta2,atan2f_Q2 nop.i 999 } { .mfi nop.m 999 fma.s1 atan2f_pRC = atan2f_rsq,atan2f_pR,atan2f_C nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_poly_u10to0 = atan2f_U6,atan2f_poly_u10to3,atan2f_poly_u210 nop.i 999 ;; } { .mfi nop.m 999 fma.s1 atan2f_pQRC = atan2f_R_numer,atan2f_Q3,atan2f_pRC nop.i 999 ;; } { .mfb nop.m 999 fma.s.s0 f8 = atan2f_U,atan2f_poly_u10to0,atan2f_pQRC br.ret.sptk b0 ;; } ATAN2F_XY_INF_NAN_ZERO: { .mfi nop.m 999 fclass.m p10,p0 = f8,0xc3 // Is y nan nop.i 999 } ;; { .mfi nop.m 999 fclass.m p12,p0 = f9,0xc3 // Is x nan nop.i 999 } ;; { .mfi nop.m 999 fclass.m p6,p0 = f9,0x21 // Is x +inf nop.i 999 } { .mfb nop.m 999 (p10) fma.s f8 = f9,f8,f0 // Result quietized y if y is nan (p10) br.ret.spnt b0 // Exit if y is nan } ;; { .mfi nop.m 999 (p6) fclass.m.unc p7,p8 = f8,0x23 // x +inf, is y inf nop.i 999 } { .mfb nop.m 999 (p12) fnorm.s f8 = f9 // Result quietized x if x is nan, y not nan (p12) br.ret.spnt b0 // Exit if x is nan, y not nan } ;; // Here if x or y inf, or x or y zero { .mfi nop.m 999 fcmp.eq.s0 p15,p0 = f8,f9 // Dummy op to set flag on denormal inputs nop.i 999 } ;; { .mfi nop.m 999 fclass.m p11,p12 = f9,0x22 // Is x -inf nop.i 999 } { .mfb nop.m 999 (p7) fma.s f8 = atan2f_sgn_Y, atan2f_const_piby4,f0 // Result +-pi/4 (p7) br.ret.spnt b0 // Exit if x +inf and y inf } ;; { .mfb nop.m 999 (p8) fmerge.s f8 = f8,f0 // If x +inf and y not inf, result +-0 (p8) br.ret.spnt b0 // Exit if x +inf and y not inf } ;; { .mfi nop.m 999 (p12) fclass.m.unc p13,p0 = f8,0x23 // x not -inf, is y inf nop.i 999 } ;; { .mfi nop.m 999 (p11) fclass.m.unc p14,p15 = f8,0x23 // x -inf, is y inf nop.i 999 } ;; { .mfi nop.m 999 fclass.m p6,p7 = f9,0x7 // Is x zero nop.i 999 } { .mfb nop.m 999 (p13) fma.s f8 = atan2f_sgn_Y, atan2f_const_piby2,f0 // Result +-pi/2 (p13) br.ret.spnt b0 // Exit if x not -inf and y inf } ;; { .mfi nop.m 999 (p14) fma.s f8 = atan2f_sgn_Y, atan2f_const_3piby4,f0 // Result +-3pi/4 nop.i 999 } { .mfb nop.m 999 (p15) fma.s f8 = atan2f_sgn_Y, atan2f_const_pi,f0 // Result +-pi (p11) br.ret.spnt b0 // Exit if x -inf } ;; // Here if x or y zero { .mfi nop.m 999 (p7) fclass.m.unc p8,p9 = f9,0x19 // x not zero, y zero, is x > zero nop.i 999 } ;; { .mfi nop.m 999 (p6) fclass.m.unc p10,p11 = f8,0x7 // x zero, is y zero nop.i 999 } ;; { .mfi nop.m 999 (p8) fmerge.s f8 = f8, f0 // x > zero and y zero, result is +-zero nop.i 999 } { .mfb nop.m 999 (p9) fma.s f8 = atan2f_sgn_Y, atan2f_const_pi,f0 // x < 0, y 0, result +-pi (p10) br.cond.spnt __libm_error_region // Branch if x zero and y zero } ;; { .mfb nop.m 999 (p11) fma.s f8 = atan2f_sgn_Y, atan2f_const_piby2,f0 // x zero, y not zero br.ret.sptk b0 // Final special case exit } ;; .endp atan2f .proc __libm_error_region __libm_error_region: .prologue mov GR_Parameter_TAG = 38 fclass.m p10,p11 = f9,0x5 // @zero | @pos ;; (p10) fmerge.s f10 = f8, f0 (p11) fma.s f10 = atan2f_sgn_Y, atan2f_const_pi,f0 ;; { .mfi add GR_Parameter_Y=-32,sp // Parameter 2 value nop.f 999 .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 stfs [GR_Parameter_Y] = f9,16 // Store 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 stfs [GR_Parameter_X] = f8 // Store Parameter 1 on stack add GR_Parameter_RESULT = 0,GR_Parameter_Y nop.b 0 // Parameter 3 address } { .mib stfs [GR_Parameter_Y] = f10 // 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 ldfs f8 = [GR_Parameter_RESULT] // Get return result off stack .restore 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 .type __libm_error_support#,@function .global __libm_error_support#