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+.file "exp.s"
+
+
+// Copyright (c) 2000 - 2005, 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
+//==============================================================
+// 2/02/00  Initial version
+// 3/07/00  exp(inf)  = inf but now does NOT call error support
+//          exp(-inf) = 0   but now does NOT call error support
+// 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.
+// 11/30/00 Reworked to shorten main path, widen main path to include all
+//          args in normal range, and add quick exit for 0, nan, inf.
+// 12/05/00 Loaded constants earlier with setf to save 2 cycles.
+// 02/05/02 Corrected uninitialize predicate in POSSIBLE_UNDERFLOW path
+// 05/20/02 Cleaned up namespace and sf0 syntax
+// 09/07/02 Force inexact flag
+// 11/15/02 Split underflow path into zero/nonzero; eliminated fma in main path
+// 05/30/03 Set inexact flag on unmasked overflow/underflow
+// 03/31/05 Reformatted delimiters between data tables
+
+// API
+//==============================================================
+// double exp(double)
+
+// Overview of operation
+//==============================================================
+// Take the input x. w is "how many log2/128 in x?"
+//  w = x * 128/log2
+//  n = int(w)
+//  x = n log2/128 + r + delta
+
+//  n = 128M + index_1 + 2^4 index_2
+//  x = M log2 + (log2/128) index_1 + (log2/8) index_2 + r + delta
+
+//  exp(x) = 2^M  2^(index_1/128)  2^(index_2/8) exp(r) exp(delta)
+//       Construct 2^M
+//       Get 2^(index_1/128) from table_1;
+//       Get 2^(index_2/8)   from table_2;
+//       Calculate exp(r) by 5th order polynomial
+//          r = x - n (log2/128)_high
+//          delta = - n (log2/128)_low
+//       Calculate exp(delta) as 1 + delta
+
+
+// Special values
+//==============================================================
+// exp(+0)    = 1.0
+// exp(-0)    = 1.0
+
+// exp(+qnan) = +qnan
+// exp(-qnan) = -qnan
+// exp(+snan) = +qnan
+// exp(-snan) = -qnan
+
+// exp(-inf)  = +0
+// exp(+inf)  = +inf
+
+// Overflow and Underflow
+//=======================
+// exp(x) = largest double normal when
+//     x = 709.7827 = 0x40862e42fefa39ef
+
+// exp(x) = smallest double normal when
+//     x = -708.396 = 0xc086232bdd7abcd2
+
+// exp(x) = largest round-to-nearest single zero when
+//     x = -745.1332 = 0xc0874910d52d3052
+
+
+// Registers used
+//==============================================================
+// Floating Point registers used:
+// f8, input, output
+// f6 -> f15,  f32 -> f49
+
+// General registers used:
+// r14 -> r40
+
+// Predicate registers used:
+// p6 -> p15
+
+// Assembly macros
+//==============================================================
+
+rRshf                 = r14
+rAD_TB1               = r15
+rAD_T1                = r15
+rAD_TB2               = r16
+rAD_T2                = r16
+rAD_P                 = r17
+rN                    = r18
+rIndex_1              = r19
+rIndex_2_16           = r20
+rM                    = r21
+rBiased_M             = r21
+rIndex_1_16           = r21
+rSig_inv_ln2          = r22
+rExp_bias             = r23
+rExp_mask             = r24
+rTmp                  = r25
+rRshf_2to56           = r26
+rGt_ln                = r27
+rExp_2tom56           = r28
+
+
+GR_SAVE_B0            = r33
+GR_SAVE_PFS           = r34
+GR_SAVE_GP            = r35
+GR_SAVE_SP            = r36
+
+GR_Parameter_X        = r37
+GR_Parameter_Y        = r38
+GR_Parameter_RESULT   = r39
+GR_Parameter_TAG      = r40
+
+
+FR_X                  = f10
+FR_Y                  = f1
+FR_RESULT             = f8
+
+fRSHF_2TO56           = f6
+fINV_LN2_2TO63        = f7
+fW_2TO56_RSH          = f9
+f2TOM56               = f11
+fP5                   = f12
+fP54                  = f12
+fP5432                = f12
+fP4                   = f13
+fP3                   = f14
+fP32                  = f14
+fP2                   = f15
+fP                    = f15
+
+fLn2_by_128_hi        = f33
+fLn2_by_128_lo        = f34
+
+fRSHF                 = f35
+fNfloat               = f36
+fNormX                = f37
+fR                    = f38
+fF                    = f39
+
+fRsq                  = f40
+f2M                   = f41
+fS1                   = f42
+fT1                   = f42
+fS2                   = f43
+fT2                   = f43
+fS                    = f43
+fWre_urm_f8           = f44
+fFtz_urm_f8           = f44
+
+fMIN_DBL_OFLOW_ARG    = f45
+fMAX_DBL_ZERO_ARG     = f46
+fMAX_DBL_NORM_ARG     = f47
+fMIN_DBL_NORM_ARG     = f48
+fGt_pln               = f49
+fTmp                  = f49
+
+
+// Data tables
+//==============================================================
+
+RODATA
+.align 16
+
+// ************* DO NOT CHANGE ORDER OF THESE TABLES ********************
+
+// double-extended 1/ln(2)
+// 3fff b8aa 3b29 5c17 f0bb be87fed0691d3e88
+// 3fff b8aa 3b29 5c17 f0bc
+// For speed the significand will be loaded directly with a movl and setf.sig
+//   and the exponent will be bias+63 instead of bias+0.  Thus subsequent
+//   computations need to scale appropriately.
+// The constant 128/ln(2) is needed for the computation of w.  This is also
+//   obtained by scaling the computations.
+//
+// Two shifting constants are loaded directly with movl and setf.d.
+//   1. fRSHF_2TO56 = 1.1000..00 * 2^(63-7)
+//        This constant is added to x*1/ln2 to shift the integer part of
+//        x*128/ln2 into the rightmost bits of the significand.
+//        The result of this fma is fW_2TO56_RSH.
+//   2. fRSHF       = 1.1000..00 * 2^(63)
+//        This constant is subtracted from fW_2TO56_RSH * 2^(-56) to give
+//        the integer part of w, n, as a floating-point number.
+//        The result of this fms is fNfloat.
+
+
+LOCAL_OBJECT_START(exp_table_1)
+data8 0x40862e42fefa39f0 // smallest dbl overflow arg, +709.7827
+data8 0xc0874910d52d3052 // largest arg for rnd-to-nearest 0 result, -745.133
+data8 0x40862e42fefa39ef // largest dbl arg to give normal dbl result, +709.7827
+data8 0xc086232bdd7abcd2 // smallest dbl arg to give normal dbl result, -708.396
+data8 0xb17217f7d1cf79ab , 0x00003ff7 // ln2/128 hi
+data8 0xc9e3b39803f2f6af , 0x00003fb7 // ln2/128 lo
+//
+// Table 1 is 2^(index_1/128) where
+// index_1 goes from 0 to 15
+//
+data8 0x8000000000000000 , 0x00003FFF
+data8 0x80B1ED4FD999AB6C , 0x00003FFF
+data8 0x8164D1F3BC030773 , 0x00003FFF
+data8 0x8218AF4373FC25EC , 0x00003FFF
+data8 0x82CD8698AC2BA1D7 , 0x00003FFF
+data8 0x8383594EEFB6EE37 , 0x00003FFF
+data8 0x843A28C3ACDE4046 , 0x00003FFF
+data8 0x84F1F656379C1A29 , 0x00003FFF
+data8 0x85AAC367CC487B15 , 0x00003FFF
+data8 0x8664915B923FBA04 , 0x00003FFF
+data8 0x871F61969E8D1010 , 0x00003FFF
+data8 0x87DB357FF698D792 , 0x00003FFF
+data8 0x88980E8092DA8527 , 0x00003FFF
+data8 0x8955EE03618E5FDD , 0x00003FFF
+data8 0x8A14D575496EFD9A , 0x00003FFF
+data8 0x8AD4C6452C728924 , 0x00003FFF
+LOCAL_OBJECT_END(exp_table_1)
+
+// Table 2 is 2^(index_1/8) where
+// index_2 goes from 0 to 7
+LOCAL_OBJECT_START(exp_table_2)
+data8 0x8000000000000000 , 0x00003FFF
+data8 0x8B95C1E3EA8BD6E7 , 0x00003FFF
+data8 0x9837F0518DB8A96F , 0x00003FFF
+data8 0xA5FED6A9B15138EA , 0x00003FFF
+data8 0xB504F333F9DE6484 , 0x00003FFF
+data8 0xC5672A115506DADD , 0x00003FFF
+data8 0xD744FCCAD69D6AF4 , 0x00003FFF
+data8 0xEAC0C6E7DD24392F , 0x00003FFF
+LOCAL_OBJECT_END(exp_table_2)
+
+
+LOCAL_OBJECT_START(exp_p_table)
+data8 0x3f8111116da21757 //P5
+data8 0x3fa55555d787761c //P4
+data8 0x3fc5555555555414 //P3
+data8 0x3fdffffffffffd6a //P2
+LOCAL_OBJECT_END(exp_p_table)
+
+
+.section .text
+GLOBAL_IEEE754_ENTRY(exp)
+
+{ .mlx
+      nop.m           0
+      movl            rSig_inv_ln2 = 0xb8aa3b295c17f0bc  // significand of 1/ln2
+}
+{ .mlx
+      addl            rAD_TB1    = @ltoff(exp_table_1), gp
+      movl            rRshf_2to56 = 0x4768000000000000   // 1.10000 2^(63+56)
+}
+;;
+
+{ .mfi
+      ld8             rAD_TB1    = [rAD_TB1]
+      fclass.m        p8,p0 = f8,0x07  // Test for x=0
+      mov             rExp_mask = 0x1ffff
+}
+{ .mfi
+      mov             rExp_bias = 0xffff
+      fnorm.s1        fNormX   = f8
+      mov             rExp_2tom56 = 0xffff-56
+}
+;;
+
+// Form two constants we need
+//  1/ln2 * 2^63  to compute  w = x * 1/ln2 * 128
+//  1.1000..000 * 2^(63+63-7) to right shift int(w) into the significand
+
+{ .mfi
+      setf.sig        fINV_LN2_2TO63 = rSig_inv_ln2 // form 1/ln2 * 2^63
+      fclass.m        p9,p0 = f8,0x22  // Test for x=-inf
+      nop.i           0
+}
+{ .mlx
+      setf.d          fRSHF_2TO56 = rRshf_2to56 // Form const 1.100 * 2^(63+56)
+      movl            rRshf = 0x43e8000000000000 // 1.10000 2^63 for right shift
+}
+;;
+
+{ .mfi
+      ldfpd           fMIN_DBL_OFLOW_ARG, fMAX_DBL_ZERO_ARG = [rAD_TB1],16
+      fclass.m        p10,p0 = f8,0x1e1  // Test for x=+inf, nan, NaT
+      nop.i           0
+}
+{ .mfb
+      setf.exp        f2TOM56 = rExp_2tom56 // form 2^-56 for scaling Nfloat
+(p9)  fma.d.s0        f8 = f0,f0,f0           // quick exit for x=-inf
+(p9)  br.ret.spnt     b0
+}
+;;
+
+{ .mfi
+      ldfpd           fMAX_DBL_NORM_ARG, fMIN_DBL_NORM_ARG = [rAD_TB1],16
+      nop.f           0
+      nop.i           0
+}
+{ .mfb
+      setf.d          fRSHF = rRshf // Form right shift const 1.100 * 2^63
+(p8)  fma.d.s0        f8 = f1,f1,f0           // quick exit for x=0
+(p8)  br.ret.spnt     b0
+}
+;;
+
+{ .mfb
+      ldfe            fLn2_by_128_hi  = [rAD_TB1],16
+(p10) fma.d.s0        f8 = f8,f8,f0  // Result if x=+inf, nan, NaT
+(p10) br.ret.spnt     b0               // quick exit for x=+inf, nan, NaT
+}
+;;
+
+{ .mfi
+      ldfe            fLn2_by_128_lo  = [rAD_TB1],16
+      fcmp.eq.s0      p6,p0 = f8, f0       // Dummy to set D
+      nop.i           0
+}
+;;
+
+// After that last load, rAD_TB1 points to the beginning of table 1
+
+// W = X * Inv_log2_by_128
+// By adding 1.10...0*2^63 we shift and get round_int(W) in significand.
+// We actually add 1.10...0*2^56 to X * Inv_log2 to do the same thing.
+
+{ .mfi
+      nop.m           0
+      fma.s1          fW_2TO56_RSH  = fNormX, fINV_LN2_2TO63, fRSHF_2TO56
+      nop.i           0
+}
+;;
+
+// Divide arguments into the following categories:
+//  Certain Underflow       p11 - -inf < x <= MAX_DBL_ZERO_ARG
+//  Possible Underflow      p13 - MAX_DBL_ZERO_ARG < x < MIN_DBL_NORM_ARG
+//  Certain Safe                - MIN_DBL_NORM_ARG <= x <= MAX_DBL_NORM_ARG
+//  Possible Overflow       p14 - MAX_DBL_NORM_ARG < x < MIN_DBL_OFLOW_ARG
+//  Certain Overflow        p15 - MIN_DBL_OFLOW_ARG <= x < +inf
+//
+// If the input is really a double arg, then there will never be
+// "Possible Overflow" arguments.
+//
+
+{ .mfi
+      add             rAD_TB2 = 0x100, rAD_TB1
+      fcmp.ge.s1      p15,p0 = fNormX,fMIN_DBL_OFLOW_ARG
+      nop.i           0
+}
+;;
+
+{ .mfi
+      add             rAD_P = 0x80, rAD_TB2
+      fcmp.le.s1      p11,p0 = fNormX,fMAX_DBL_ZERO_ARG
+      nop.i           0
+}
+;;
+
+{ .mfb
+      ldfpd           fP5, fP4  = [rAD_P] ,16
+      fcmp.gt.s1      p14,p0 = fNormX,fMAX_DBL_NORM_ARG
+(p15) br.cond.spnt    EXP_CERTAIN_OVERFLOW
+}
+;;
+
+// Nfloat = round_int(W)
+// The signficand of fW_2TO56_RSH contains the rounded integer part of W,
+// as a twos complement number in the lower bits (that is, it may be negative).
+// That twos complement number (called N) is put into rN.
+
+// Since fW_2TO56_RSH is scaled by 2^56, it must be multiplied by 2^-56
+// before the shift constant 1.10000 * 2^63 is subtracted to yield fNfloat.
+// Thus, fNfloat contains the floating point version of N
+
+{ .mfb
+      ldfpd           fP3, fP2  = [rAD_P]
+      fms.s1          fNfloat = fW_2TO56_RSH, f2TOM56, fRSHF
+(p11) br.cond.spnt    EXP_CERTAIN_UNDERFLOW
+}
+;;
+
+{ .mfi
+      getf.sig        rN        = fW_2TO56_RSH
+      nop.f           0
+      nop.i           0
+}
+;;
+
+// rIndex_1 has index_1
+// rIndex_2_16 has index_2 * 16
+// rBiased_M has M
+// rIndex_1_16 has index_1 * 16
+
+// rM has true M
+// r = x - Nfloat * ln2_by_128_hi
+// f = 1 - Nfloat * ln2_by_128_lo
+{ .mfi
+      and             rIndex_1 = 0x0f, rN
+      fnma.s1         fR   = fNfloat, fLn2_by_128_hi, fNormX
+      shr             rM = rN,  0x7
+}
+{ .mfi
+      and             rIndex_2_16 = 0x70, rN
+      fnma.s1         fF   = fNfloat, fLn2_by_128_lo, f1
+      nop.i           0
+}
+;;
+
+// rAD_T1 has address of T1
+// rAD_T2 has address if T2
+
+{ .mmi
+      add             rBiased_M = rExp_bias, rM
+      add             rAD_T2 = rAD_TB2, rIndex_2_16
+      shladd          rAD_T1 = rIndex_1, 4, rAD_TB1
+}
+;;
+
+// Create Scale = 2^M
+{ .mmi
+      setf.exp        f2M = rBiased_M
+      ldfe            fT2  = [rAD_T2]
+      nop.i           0
+}
+;;
+
+// Load T1 and T2
+{ .mfi
+      ldfe            fT1  = [rAD_T1]
+      fmpy.s0         fTmp = fLn2_by_128_lo, fLn2_by_128_lo // Force inexact
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fma.s1          fRsq = fR, fR, f0
+      nop.i           0
+}
+{ .mfi
+      nop.m           0
+      fma.s1          fP54 = fR, fP5, fP4
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fcmp.lt.s1      p13,p0 = fNormX,fMIN_DBL_NORM_ARG
+      nop.i           0
+}
+{ .mfi
+      nop.m           0
+      fma.s1          fP32 = fR, fP3, fP2
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fma.s1          fP5432  = fRsq, fP54, fP32
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fma.s1          fS1  = f2M,fT1,f0
+      nop.i           0
+}
+{ .mfi
+      nop.m           0
+      fma.s1          fS2  = fF,fT2,f0
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fma.s1          fP     = fRsq, fP5432, fR
+      nop.i           0
+}
+{ .mfi
+      nop.m           0
+      fma.s1          fS   = fS1,fS2,f0
+      nop.i           0
+}
+;;
+
+{ .mbb
+      nop.m           0
+(p13) br.cond.spnt    EXP_POSSIBLE_UNDERFLOW
+(p14) br.cond.spnt    EXP_POSSIBLE_OVERFLOW
+}
+;;
+
+{ .mfb
+      nop.m           0
+      fma.d.s0        f8 = fS, fP, fS
+      br.ret.sptk     b0                  // Normal path exit
+}
+;;
+
+
+EXP_POSSIBLE_OVERFLOW:
+
+// Here if fMAX_DBL_NORM_ARG < x < fMIN_DBL_OFLOW_ARG
+// This cannot happen if input is a double, only if input higher precision.
+// Overflow is a possibility, not a certainty.
+
+// Recompute result using status field 2 with user's rounding mode,
+// and wre set.  If result is larger than largest double, then we have
+// overflow
+
+{ .mfi
+      mov             rGt_ln  = 0x103ff // Exponent for largest dbl + 1 ulp
+      fsetc.s2        0x7F,0x42         // Get user's round mode, set wre
+      nop.i           0
+}
+;;
+
+{ .mfi
+      setf.exp        fGt_pln = rGt_ln  // Create largest double + 1 ulp
+      fma.d.s2        fWre_urm_f8 = fS, fP, fS    // Result with wre set
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fsetc.s2        0x7F,0x40                   // Turn off wre in sf2
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fcmp.ge.s1      p6, p0 =  fWre_urm_f8, fGt_pln // Test for overflow
+      nop.i           0
+}
+;;
+
+{ .mfb
+      nop.m           0
+      nop.f           0
+(p6)  br.cond.spnt    EXP_CERTAIN_OVERFLOW // Branch if overflow
+}
+;;
+
+{ .mfb
+      nop.m           0
+      fma.d.s0        f8 = fS, fP, fS
+      br.ret.sptk     b0                     // Exit if really no overflow
+}
+;;
+
+EXP_CERTAIN_OVERFLOW:
+{ .mmi
+      sub             rTmp = rExp_mask, r0, 1
+;;
+      setf.exp        fTmp = rTmp
+      nop.i           0
+}
+;;
+
+{ .mfi
+      alloc           r32=ar.pfs,1,4,4,0
+      fmerge.s        FR_X = f8,f8
+      nop.i           0
+}
+{ .mfb
+      mov             GR_Parameter_TAG = 14
+      fma.d.s0        FR_RESULT = fTmp, fTmp, fTmp    // Set I,O and +INF result
+      br.cond.sptk    __libm_error_region
+}
+;;
+
+EXP_POSSIBLE_UNDERFLOW:
+
+// Here if fMAX_DBL_ZERO_ARG < x < fMIN_DBL_NORM_ARG
+// Underflow is a possibility, not a certainty
+
+// We define an underflow when the answer with
+//    ftz set
+// is zero (tiny numbers become zero)
+
+// Notice (from below) that if we have an unlimited exponent range,
+// then there is an extra machine number E between the largest denormal and
+// the smallest normal.
+
+// So if with unbounded exponent we round to E or below, then we are
+// tiny and underflow has occurred.
+
+// But notice that you can be in a situation where we are tiny, namely
+// rounded to E, but when the exponent is bounded we round to smallest
+// normal. So the answer can be the smallest normal with underflow.
+
+//                           E
+// -----+--------------------+--------------------+-----
+//      |                    |                    |
+//   1.1...10 2^-3fff    1.1...11 2^-3fff    1.0...00 2^-3ffe
+//   0.1...11 2^-3ffe                                   (biased, 1)
+//    largest dn                               smallest normal
+
+{ .mfi
+      nop.m           0
+      fsetc.s2        0x7F,0x41                // Get user's round mode, set ftz
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fma.d.s2        fFtz_urm_f8 = fS, fP, fS // Result with ftz set
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fsetc.s2        0x7F,0x40                // Turn off ftz in sf2
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fcmp.eq.s1      p6, p7 = fFtz_urm_f8, f0 // Test for underflow
+      nop.i           0
+}
+{ .mfi
+      nop.m           0
+      fma.d.s0        f8 = fS, fP, fS          // Compute result, set I, maybe U
+      nop.i           0
+}
+;;
+
+{ .mbb
+      nop.m           0
+(p6)  br.cond.spnt    EXP_UNDERFLOW_COMMON     // Branch if really underflow
+(p7)  br.ret.sptk     b0                       // Exit if really no underflow
+}
+;;
+
+EXP_CERTAIN_UNDERFLOW:
+// Here if  x < fMAX_DBL_ZERO_ARG
+// Result will be zero (or smallest denorm if round to +inf) with I, U set
+{ .mmi
+      mov             rTmp = 1
+;;
+      setf.exp        fTmp = rTmp               // Form small normal
+      nop.i           0
+}
+;;
+
+{ .mfi
+      nop.m           0
+      fmerge.se       fTmp = fTmp, fLn2_by_128_lo // Small with signif lsb 1
+      nop.i           0
+}
+;;
+
+{ .mfb
+      nop.m           0
+      fma.d.s0        f8 = fTmp, fTmp, f0 // Set I,U, tiny (+0.0) result
+      br.cond.sptk    EXP_UNDERFLOW_COMMON
+}
+;;
+
+EXP_UNDERFLOW_COMMON:
+// Determine if underflow result is zero or nonzero
+{ .mfi
+      alloc           r32=ar.pfs,1,4,4,0
+      fcmp.eq.s1      p6, p0 =  f8, f0
+      nop.i           0
+}
+;;
+
+{ .mfb
+      nop.m           0
+      fmerge.s        FR_X = fNormX,fNormX
+(p6)  br.cond.spnt    EXP_UNDERFLOW_ZERO
+}
+;;
+
+EXP_UNDERFLOW_NONZERO:
+// Here if  x < fMIN_DBL_NORM_ARG and result nonzero;
+// I, U are set
+{ .mfb
+      mov             GR_Parameter_TAG = 15
+      nop.f           0                         // FR_RESULT already set
+      br.cond.sptk    __libm_error_region
+}
+;;
+
+EXP_UNDERFLOW_ZERO:
+// Here if x < fMIN_DBL_NORM_ARG and result zero;
+// I, U are set
+{ .mfb
+      mov             GR_Parameter_TAG = 15
+      nop.f           0                         // FR_RESULT already set
+      br.cond.sptk    __libm_error_region
+}
+;;
+
+GLOBAL_IEEE754_END(exp)
+
+
+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#