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Diffstat (limited to 'sysdeps/ia64/fpu/e_acos.S')
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diff --git a/sysdeps/ia64/fpu/e_acos.S b/sysdeps/ia64/fpu/e_acos.S new file mode 100644 index 0000000000..c2b31ab85e --- /dev/null +++ b/sysdeps/ia64/fpu/e_acos.S @@ -0,0 +1,878 @@ +.file "acos.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 +// 08/17/00 New and much faster algorithm. +// 08/30/00 Avoided bank conflicts on loads, shortened |x|=1 and x=0 paths, +// fixed mfb split issue stalls. +// 05/20/02 Cleaned up namespace and sf0 syntax +// 08/02/02 New and much faster algorithm II +// 02/06/03 Reordered header: .section, .global, .proc, .align + +// Description +//========================================= +// The acos function computes the principal value of the arc cosine of x. +// acos(0) returns Pi/2, acos(1) returns 0, acos(-1) returns Pi. +// A doman error occurs for arguments not in the range [-1,+1]. +// +// The acos function returns the arc cosine in the range [0, Pi] radians. +// +// There are 8 paths: +// 1. x = +/-0.0 +// Return acos(x) = Pi/2 + x +// +// 2. 0.0 < |x| < 0.625 +// Return acos(x) = Pi/2 - x - x^3 *PolA(x^2) +// where PolA(x^2) = A3 + A5*x^2 + A7*x^4 +...+ A35*x^32 +// +// 3. 0.625 <=|x| < 1.0 +// Return acos(x) = Pi/2 - asin(x) = +// = Pi/2 - sign(x) * ( Pi/2 - sqrt(R) * PolB(R)) +// Where R = 1 - |x|, +// PolB(R) = B0 + B1*R + B2*R^2 +...+B12*R^12 +// +// sqrt(R) is approximated using the following sequence: +// y0 = (1 + eps)/sqrt(R) - initial approximation by frsqrta, +// |eps| < 2^(-8) +// Then 3 iterations are used to refine the result: +// H0 = 0.5*y0 +// S0 = R*y0 +// +// d0 = 0.5 - H0*S0 +// H1 = H0 + d0*H0 +// S1 = S0 + d0*S0 +// +// d1 = 0.5 - H1*S1 +// H2 = H1 + d0*H1 +// S2 = S1 + d0*S1 +// +// d2 = 0.5 - H2*S2 +// S3 = S3 + d2*S3 +// +// S3 approximates sqrt(R) with enough accuracy for this algorithm +// +// So, the result should be reconstracted as follows: +// acos(x) = Pi/2 - sign(x) * (Pi/2 - S3*PolB(R)) +// +// But for optimization purposes the reconstruction step is slightly +// changed: +// acos(x) = Cpi + sign(x)*PolB(R)*S2 - sign(x)*d2*S2*PolB(R) +// where Cpi = 0 if x > 0 and Cpi = Pi if x < 0 +// +// 4. |x| = 1.0 +// Return acos(1.0) = 0.0, acos(-1.0) = Pi +// +// 5. 1.0 < |x| <= +INF +// A doman error occurs for arguments not in the range [-1,+1] +// +// 6. x = [S,Q]NaN +// Return acos(x) = QNaN +// +// 7. x is denormal +// Return acos(x) = Pi/2 - x, +// +// 8. x is unnormal +// Normalize input in f8 and return to the very beginning of the function +// +// Registers used +//============================================================== +// Floating Point registers used: +// f8, input, output +// f6, f7, f9 -> f15, f32 -> f64 + +// General registers used: +// r3, r21 -> r31, r32 -> r38 + +// Predicate registers used: +// p0, p6 -> p14 + +// +// Assembly macros +//========================================= +// integer registers used +// scratch +rTblAddr = r3 + +rPiBy2Ptr = r21 +rTmpPtr3 = r22 +rDenoBound = r23 +rOne = r24 +rAbsXBits = r25 +rHalf = r26 +r0625 = r27 +rSign = r28 +rXBits = r29 +rTmpPtr2 = r30 +rTmpPtr1 = r31 + +// stacked +GR_SAVE_PFS = r32 +GR_SAVE_B0 = r33 +GR_SAVE_GP = r34 +GR_Parameter_X = r35 +GR_Parameter_Y = r36 +GR_Parameter_RESULT = r37 +GR_Parameter_TAG = r38 + +// floating point registers used +FR_X = f10 +FR_Y = f1 +FR_RESULT = f8 + + +// scratch +fXSqr = f6 +fXCube = f7 +fXQuadr = f9 +f1pX = f10 +f1mX = f11 +f1pXRcp = f12 +f1mXRcp = f13 +fH = f14 +fS = f15 +// stacked +fA3 = f32 +fB1 = f32 +fA5 = f33 +fB2 = f33 +fA7 = f34 +fPiBy2 = f34 +fA9 = f35 +fA11 = f36 +fB10 = f35 +fB11 = f36 +fA13 = f37 +fA15 = f38 +fB4 = f37 +fB5 = f38 +fA17 = f39 +fA19 = f40 +fB6 = f39 +fB7 = f40 +fA21 = f41 +fA23 = f42 +fB3 = f41 +fB8 = f42 +fA25 = f43 +fA27 = f44 +fB9 = f43 +fB12 = f44 +fA29 = f45 +fA31 = f46 +fA33 = f47 +fA35 = f48 +fBaseP = f49 +fB0 = f50 +fSignedS = f51 +fD = f52 +fHalf = f53 +fR = f54 +fCloseTo1Pol = f55 +fSignX = f56 +fDenoBound = f57 +fNormX = f58 +fX8 = f59 +fRSqr = f60 +fRQuadr = f61 +fR8 = f62 +fX16 = f63 +fCpi = f64 + +// Data tables +//============================================================== +RODATA +.align 16 +LOCAL_OBJECT_START(acos_base_range_table) +// Ai: Polynomial coefficients for the acos(x), |x| < .625000 +// Bi: Polynomial coefficients for the acos(x), |x| > .625000 +data8 0xBFDAAB56C01AE468 //A29 +data8 0x3FE1C470B76A5B2B //A31 +data8 0xBFDC5FF82A0C4205 //A33 +data8 0x3FC71FD88BFE93F0 //A35 +data8 0xB504F333F9DE6487, 0x00003FFF //B0 +data8 0xAAAAAAAAAAAAFC18, 0x00003FFC //A3 +data8 0x3F9F1C71BC4A7823 //A9 +data8 0x3F96E8BBAAB216B2 //A11 +data8 0x3F91C4CA1F9F8A98 //A13 +data8 0x3F8C9DDCEDEBE7A6 //A15 +data8 0x3F877784442B1516 //A17 +data8 0x3F859C0491802BA2 //A19 +data8 0x9999999998C88B8F, 0x00003FFB //A5 +data8 0x3F6BD7A9A660BF5E //A21 +data8 0x3F9FC1659340419D //A23 +data8 0xB6DB6DB798149BDF, 0x00003FFA //A7 +data8 0xBFB3EF18964D3ED3 //A25 +data8 0x3FCD285315542CF2 //A27 +data8 0xF15BEEEFF7D2966A, 0x00003FFB //B1 +data8 0x3EF0DDA376D10FB3 //B10 +data8 0xBEB83CAFE05EBAC9 //B11 +data8 0x3F65FFB67B513644 //B4 +data8 0x3F5032FBB86A4501 //B5 +data8 0x3F392162276C7CBA //B6 +data8 0x3F2435949FD98BDF //B7 +data8 0xD93923D7FA08341C, 0x00003FF9 //B2 +data8 0x3F802995B6D90BDB //B3 +data8 0x3F10DF86B341A63F //B8 +data8 0xC90FDAA22168C235, 0x00003FFF // Pi/2 +data8 0x3EFA3EBD6B0ECB9D //B9 +data8 0x3EDE18BA080E9098 //B12 +LOCAL_OBJECT_END(acos_base_range_table) + +.section .text +GLOBAL_LIBM_ENTRY(acos) +acos_unnormal_back: +{ .mfi + getf.d rXBits = f8 // grab bits of input value + // set p12 = 1 if x is a NaN, denormal, or zero + fclass.m p12, p0 = f8, 0xcf + adds rSign = 1, r0 +} +{ .mfi + addl rTblAddr = @ltoff(acos_base_range_table),gp + // 1 - x = 1 - |x| for positive x + fms.s1 f1mX = f1, f1, f8 + addl rHalf = 0xFFFE, r0 // exponent of 1/2 +} +;; +{ .mfi + addl r0625 = 0x3FE4, r0 // high 16 bits of 0.625 + // set p8 = 1 if x < 0 + fcmp.lt.s1 p8, p9 = f8, f0 + shl rSign = rSign, 63 // sign bit +} +{ .mfi + // point to the beginning of the table + ld8 rTblAddr = [rTblAddr] + // 1 + x = 1 - |x| for negative x + fma.s1 f1pX = f1, f1, f8 + adds rOne = 0x3FF, r0 +} +;; +{ .mfi + andcm rAbsXBits = rXBits, rSign // bits of |x| + fmerge.s fSignX = f8, f1 // signum(x) + shl r0625 = r0625, 48 // bits of DP representation of 0.625 +} +{ .mfb + setf.exp fHalf = rHalf // load A2 to FP reg + fma.s1 fXSqr = f8, f8, f0 // x^2 + // branch on special path if x is a NaN, denormal, or zero +(p12) br.cond.spnt acos_special +} +;; +{ .mfi + adds rPiBy2Ptr = 272, rTblAddr + nop.f 0 + shl rOne = rOne, 52 // bits of 1.0 +} +{ .mfi + adds rTmpPtr1 = 16, rTblAddr + nop.f 0 + // set p6 = 1 if |x| < 0.625 + cmp.lt p6, p7 = rAbsXBits, r0625 +} +;; +{ .mfi + ldfpd fA29, fA31 = [rTblAddr] // A29, fA31 + // 1 - x = 1 - |x| for positive x +(p9) fms.s1 fR = f1, f1, f8 + // point to coefficient of "near 1" polynomial +(p7) adds rTmpPtr2 = 176, rTblAddr +} +{ .mfi + ldfpd fA33, fA35 = [rTmpPtr1], 16 // A33, fA35 + // 1 + x = 1 - |x| for negative x +(p8) fma.s1 fR = f1, f1, f8 +(p6) adds rTmpPtr2 = 48, rTblAddr +} +;; +{ .mfi + ldfe fB0 = [rTmpPtr1], 16 // B0 + nop.f 0 + nop.i 0 +} +{ .mib + adds rTmpPtr3 = 16, rTmpPtr2 + // set p10 = 1 if |x| = 1.0 + cmp.eq p10, p0 = rAbsXBits, rOne + // branch on special path for |x| = 1.0 +(p10) br.cond.spnt acos_abs_1 +} +;; +{ .mfi + ldfe fA3 = [rTmpPtr2], 48 // A3 or B1 + nop.f 0 + adds rTmpPtr1 = 64, rTmpPtr3 +} +{ .mib + ldfpd fA9, fA11 = [rTmpPtr3], 16 // A9, A11 or B10, B11 + // set p11 = 1 if |x| > 1.0 + cmp.gt p11, p0 = rAbsXBits, rOne + // branch on special path for |x| > 1.0 +(p11) br.cond.spnt acos_abs_gt_1 +} +;; +{ .mfi + ldfpd fA17, fA19 = [rTmpPtr2], 16 // A17, A19 or B6, B7 + // initial approximation of 1 / sqrt(1 - x) + frsqrta.s1 f1mXRcp, p0 = f1mX + nop.i 0 +} +{ .mfi + ldfpd fA13, fA15 = [rTmpPtr3] // A13, A15 or B4, B5 + fma.s1 fXCube = fXSqr, f8, f0 // x^3 + nop.i 0 +} +;; +{ .mfi + ldfe fA5 = [rTmpPtr2], 48 // A5 or B2 + // initial approximation of 1 / sqrt(1 + x) + frsqrta.s1 f1pXRcp, p0 = f1pX + nop.i 0 +} +{ .mfi + ldfpd fA21, fA23 = [rTmpPtr1], 16 // A21, A23 or B3, B8 + fma.s1 fXQuadr = fXSqr, fXSqr, f0 // x^4 + nop.i 0 +} +;; +{ .mfi + ldfe fA7 = [rTmpPtr1] // A7 or Pi/2 + fma.s1 fRSqr = fR, fR, f0 // R^2 + nop.i 0 +} +{ .mfb + ldfpd fA25, fA27 = [rTmpPtr2] // A25, A27 or B9, B12 + nop.f 0 +(p6) br.cond.spnt acos_base_range; +} +;; + +{ .mfi + nop.m 0 +(p9) fma.s1 fH = fHalf, f1mXRcp, f0 // H0 for x > 0 + nop.i 0 +} +{ .mfi + nop.m 0 +(p9) fma.s1 fS = f1mX, f1mXRcp, f0 // S0 for x > 0 + nop.i 0 +} +;; +{ .mfi + nop.m 0 +(p8) fma.s1 fH = fHalf, f1pXRcp, f0 // H0 for x < 0 + nop.i 0 +} +{ .mfi + nop.m 0 +(p8) fma.s1 fS = f1pX, f1pXRcp, f0 // S0 for x > 0 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fRQuadr = fRSqr, fRSqr, f0 // R^4 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fB11 = fB11, fR, fB10 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fB1 = fB1, fR, fB0 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fB5 = fB5, fR, fB4 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fB7 = fB7, fR, fB6 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fB3 = fB3, fR, fB2 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fnma.s1 fD = fH, fS, fHalf // d0 = 1/2 - H0*S0 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fR8 = fRQuadr, fRQuadr, f0 // R^4 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fB9 = fB9, fR, fB8 + nop.i 0 +} +;; +{.mfi + nop.m 0 + fma.s1 fB12 = fB12, fRSqr, fB11 + nop.i 0 +} +{.mfi + nop.m 0 + fma.s1 fB7 = fB7, fRSqr, fB5 + nop.i 0 +} +;; +{.mfi + nop.m 0 + fma.s1 fB3 = fB3, fRSqr, fB1 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fH = fH, fD, fH // H1 = H0 + H0*d0 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fS = fS, fD, fS // S1 = S0 + S0*d0 + nop.i 0 +} +;; +{.mfi + nop.m 0 +(p9) fma.s1 fCpi = f1, f0, f0 // Cpi = 0 if x > 0 + nop.i 0 +} +{ .mfi + nop.m 0 +(p8) fma.s1 fCpi = fPiBy2, f1, fPiBy2 // Cpi = Pi if x < 0 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fB12 = fB12, fRSqr, fB9 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fB7 = fB7, fRQuadr, fB3 + nop.i 0 +} +;; +{.mfi + nop.m 0 + fnma.s1 fD = fH, fS, fHalf // d1 = 1/2 - H1*S1 + nop.i 0 +} +{ .mfi + nop.m 0 + fnma.s1 fSignedS = fSignX, fS, f0 // -signum(x)*S1 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fCloseTo1Pol = fB12, fR8, fB7 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fH = fH, fD, fH // H2 = H1 + H1*d1 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fS = fS, fD, fS // S2 = S1 + S1*d1 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + // -signum(x)* S2 = -signum(x)*(S1 + S1*d1) + fma.s1 fSignedS = fSignedS, fD, fSignedS + nop.i 0 +} +;; +{.mfi + nop.m 0 + fnma.s1 fD = fH, fS, fHalf // d2 = 1/2 - H2*S2 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + // Cpi + signum(x)*PolB*S2 + fnma.s1 fCpi = fSignedS, fCloseTo1Pol, fCpi + nop.i 0 +} +{ .mfi + nop.m 0 + // signum(x)*PolB * S2 + fnma.s1 fCloseTo1Pol = fSignedS, fCloseTo1Pol, f0 + nop.i 0 +} +;; +{ .mfb + nop.m 0 + // final result for 0.625 <= |x| < 1 + fma.d.s0 f8 = fCloseTo1Pol, fD, fCpi + // exit here for 0.625 <= |x| < 1 + br.ret.sptk b0 +} +;; + + +// here if |x| < 0.625 +.align 32 +acos_base_range: +{ .mfi + ldfe fCpi = [rPiBy2Ptr] // Pi/2 + fma.s1 fA33 = fA33, fXSqr, fA31 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA15 = fA15, fXSqr, fA13 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA29 = fA29, fXSqr, fA27 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA25 = fA25, fXSqr, fA23 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA21 = fA21, fXSqr, fA19 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA9 = fA9, fXSqr, fA7 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA5 = fA5, fXSqr, fA3 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA35 = fA35, fXQuadr, fA33 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA17 = fA17, fXQuadr, fA15 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fX8 = fXQuadr, fXQuadr, f0 // x^8 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA25 = fA25, fXQuadr, fA21 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA9 = fA9, fXQuadr, fA5 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fms.s1 fCpi = fCpi, f1, f8 // Pi/2 - x + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA35 = fA35, fXQuadr, fA29 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA17 = fA17, fXSqr, fA11 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fX16 = fX8, fX8, f0 // x^16 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fA35 = fA35, fX8, fA25 + nop.i 0 +} +{ .mfi + nop.m 0 + fma.s1 fA17 = fA17, fX8, fA9 + nop.i 0 +} +;; +{ .mfi + nop.m 0 + fma.s1 fBaseP = fA35, fX16, fA17 + nop.i 0 +} +;; +{ .mfb + nop.m 0 + // final result for |x| < 0.625 + fnma.d.s0 f8 = fBaseP, fXCube, fCpi + // exit here for |x| < 0.625 path + br.ret.sptk b0 +} +;; + +// here if |x| = 1 +// acos(1) = 0 +// acos(-1) = Pi +.align 32 +acos_abs_1: +{ .mfi + ldfe fPiBy2 = [rPiBy2Ptr] // Pi/2 + nop.f 0 + nop.i 0 +} +;; +.pred.rel "mutex", p8, p9 +{ .mfi + nop.m 0 + // result for x = 1.0 +(p9) fma.d.s0 f8 = f1, f0, f0 // 0.0 + nop.i 0 +} +{.mfb + nop.m 0 + // result for x = -1.0 +(p8) fma.d.s0 f8 = fPiBy2, f1, fPiBy2 // Pi + // exit here for |x| = 1.0 + br.ret.sptk b0 +} +;; + +// here if x is a NaN, denormal, or zero +.align 32 +acos_special: +{ .mfi + // point to Pi/2 + adds rPiBy2Ptr = 272, rTblAddr + // set p12 = 1 if x is a NaN + fclass.m p12, p0 = f8, 0xc3 + nop.i 0 +} +{ .mlx + nop.m 0 + // smallest positive DP normalized number + movl rDenoBound = 0x0010000000000000 +} +;; +{ .mfi + ldfe fPiBy2 = [rPiBy2Ptr] // Pi/2 + // set p13 = 1 if x = 0.0 + fclass.m p13, p0 = f8, 0x07 + nop.i 0 +} +{ .mfi + nop.m 0 + fnorm.s1 fNormX = f8 + nop.i 0 +} +;; +{ .mfb + // load smallest normal to FP reg + setf.d fDenoBound = rDenoBound + // answer if x is a NaN +(p12) fma.d.s0 f8 = f8,f1,f0 + // exit here if x is a NaN +(p12) br.ret.spnt b0 +} +;; +{ .mfi + nop.m 0 + // absolute value of normalized x + fmerge.s fNormX = f1, fNormX + nop.i 0 +} +;; +{ .mfb + nop.m 0 + // final result for x = 0 +(p13) fma.d.s0 f8 = fPiBy2, f1, f8 + // exit here if x = 0.0 +(p13) br.ret.spnt b0 +} +;; +// if we still here then x is denormal or unnormal +{ .mfi + nop.m 0 + // set p14 = 1 if normalized x is greater than or + // equal to the smallest denormalized value + // So, if p14 is set to 1 it means that we deal with + // unnormal rather than with "true" denormal + fcmp.ge.s1 p14, p0 = fNormX, fDenoBound + nop.i 0 +} +;; +{ .mfi + nop.m 0 +(p14) fcmp.eq.s0 p6, p0 = f8, f0 // Set D flag if x unnormal + nop.i 0 +} +{ .mfb + nop.m 0 + // normalize unnormal input +(p14) fnorm.s1 f8 = f8 + // return to the main path +(p14) br.cond.sptk acos_unnormal_back +} +;; +// if we still here it means that input is "true" denormal +{ .mfb + nop.m 0 + // final result if x is denormal + fms.d.s0 f8 = fPiBy2, f1, f8 // Pi/2 - x + // exit here if x is denormal + br.ret.sptk b0 +} +;; + +// here if |x| > 1.0 +// error handler should be called +.align 32 +acos_abs_gt_1: +{ .mfi + alloc r32 = ar.pfs, 0, 3, 4, 0 // get some registers + fmerge.s FR_X = f8,f8 + nop.i 0 +} +{ .mfb + mov GR_Parameter_TAG = 58 // error code + frcpa.s0 FR_RESULT, p0 = f0,f0 + // call error handler routine + br.cond.sptk __libm_error_region +} +;; +GLOBAL_LIBM_END(acos) + + + +LOCAL_LIBM_ENTRY(__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 + stfd [GR_Parameter_Y] = FR_Y,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 + stfd [GR_Parameter_X] = FR_X // STORE Parameter 1 on stack + add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address + nop.b 0 +} +{ .mib + stfd [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 + add GR_Parameter_RESULT = 48,sp + nop.m 0 + nop.i 0 +};; +{ .mmi + ldfd 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 +};; + +LOCAL_LIBM_END(__libm_error_region) +.type __libm_error_support#,@function +.global __libm_error_support# |