glibc/sysdeps/ia64/fpu/s_expm1.S

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.file "exp_m1.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
//==============================================================
// 02/02/00 Initial Version
// 04/04/00 Unwind support added
// 08/15/00 Bundle added after call to __libm_error_support to properly
// set [the previously overwritten] GR_Parameter_RESULT.
// 07/07/01 Improved speed of all paths
// 05/20/02 Cleaned up namespace and sf0 syntax
// 11/20/02 Improved speed, algorithm based on exp
// 03/31/05 Reformatted delimiters between data tables
// API
//==============================================================
// double expm1(double)
// Overview of operation
//==============================================================
// 1. Inputs of Nan, Inf, Zero, NatVal handled with special paths
//
// 2. |x| < 2^-60
// Result = x, computed by x + x*x to handle appropriate flags and rounding
//
// 3. 2^-60 <= |x| < 2^-2
// Result determined by 13th order Taylor series polynomial
// expm1f(x) = x + Q2*x^2 + ... + Q13*x^13
//
// 4. x < -48.0
// Here we know result is essentially -1 + eps, where eps only affects
// rounded result. Set I.
//
// 5. x >= 709.7827
// Result overflows. Set I, O, and call error support
//
// 6. 2^-2 <= x < 709.7827 or -48.0 <= x < -2^-2
// This is the main path. The algorithm is described below:
// 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 series by 5th order polynomial
// r = x - n (log2/128)_high
// delta = - n (log2/128)_low
// Calculate exp(delta) as 1 + delta
// Special values
//==============================================================
// expm1(+0) = +0.0
// expm1(-0) = -0.0
// expm1(+qnan) = +qnan
// expm1(-qnan) = -qnan
// expm1(+snan) = +qnan
// expm1(-snan) = -qnan
// expm1(-inf) = -1.0
// expm1(+inf) = +inf
// Overflow and Underflow
//=======================
// expm1(x) = largest double normal when
// x = 709.7827 = 40862e42fefa39ef
//
// Underflow is handled as described in case 2 above.
// Registers used
//==============================================================
// Floating Point registers used:
// f8, input
// f9 -> f15, f32 -> f75
// 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_Ln2_lo = r17
rAD_P = r17
rN = r18
rIndex_1 = r19
rIndex_2_16 = r20
rM = r21
rBiased_M = r21
rIndex_1_16 = r22
rSignexp_x = r23
rExp_x = r24
rSig_inv_ln2 = r25
rAD_Q1 = r26
rAD_Q2 = r27
rTmp = r27
rExp_bias = r28
rExp_mask = r29
rRshf_2to56 = r30
rGt_ln = r31
rExp_2tom56 = r31
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 = f50
fP5432 = f50
fP4 = f13
fP3 = f14
fP32 = f14
fP2 = f15
fLn2_by_128_hi = f33
fLn2_by_128_lo = f34
fRSHF = f35
fNfloat = f36
fW = f37
fR = f38
fF = f39
fRsq = f40
fRcube = f41
f2M = f42
fS1 = f43
fT1 = f44
fMIN_DBL_OFLOW_ARG = f45
fMAX_DBL_MINUS_1_ARG = f46
fMAX_DBL_NORM_ARG = f47
fP_lo = f51
fP_hi = f52
fP = f53
fS = f54
fNormX = f56
fWre_urm_f8 = f57
fGt_pln = f58
fTmp = f58
fS2 = f59
fT2 = f60
fSm1 = f61
fXsq = f62
fX6 = f63
fX4 = f63
fQ7 = f64
fQ76 = f64
fQ7654 = f64
fQ765432 = f64
fQ6 = f65
fQ5 = f66
fQ54 = f66
fQ4 = f67
fQ3 = f68
fQ32 = f68
fQ2 = f69
fQD = f70
fQDC = f70
fQDCBA = f70
fQDCBA98 = f70
fQDCBA98765432 = f70
fQC = f71
fQB = f72
fQBA = f72
fQA = f73
fQ9 = f74
fQ98 = f74
fQ8 = f75
// 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
data8 0xc048000000000000 // approx largest arg for minus one result
data8 0x40862e42fefa39ef // largest dbl arg to give normal dbl result
data8 0x0 // pad
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)
LOCAL_OBJECT_START(exp_Q1_table)
data8 0x3de6124613a86d09 // QD = 1/13!
data8 0x3e21eed8eff8d898 // QC = 1/12!
data8 0x3ec71de3a556c734 // Q9 = 1/9!
data8 0x3efa01a01a01a01a // Q8 = 1/8!
data8 0x8888888888888889,0x3ff8 // Q5 = 1/5!
data8 0xaaaaaaaaaaaaaaab,0x3ffc // Q3 = 1/3!
data8 0x0,0x0 // Pad to avoid bank conflicts
LOCAL_OBJECT_END(exp_Q1_table)
LOCAL_OBJECT_START(exp_Q2_table)
data8 0x3e5ae64567f544e4 // QB = 1/11!
data8 0x3e927e4fb7789f5c // QA = 1/10!
data8 0x3f2a01a01a01a01a // Q7 = 1/7!
data8 0x3f56c16c16c16c17 // Q6 = 1/6!
data8 0xaaaaaaaaaaaaaaab,0x3ffa // Q4 = 1/4!
data8 0x8000000000000000,0x3ffe // Q2 = 1/2!
LOCAL_OBJECT_END(exp_Q2_table)
.section .text
GLOBAL_IEEE754_ENTRY(expm1)
{ .mlx
getf.exp rSignexp_x = f8 // Must recompute if x unorm
movl rSig_inv_ln2 = 0xb8aa3b295c17f0bc // signif of 1/ln2
}
{ .mlx
addl rAD_TB1 = @ltoff(exp_Table_1), gp
movl rRshf_2to56 = 0x4768000000000000 // 1.10000 2^(63+56)
}
;;
// We do this fnorm right at the beginning to normalize
// any input unnormals so that SWA is not taken.
{ .mfi
ld8 rAD_TB1 = [rAD_TB1]
fclass.m p6,p0 = f8,0x0b // Test for x=unorm
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 p8,p0 = f8,0x07 // Test for x=0
nop.i 0
}
{ .mlx
setf.d fRSHF_2TO56 = rRshf_2to56 // Form 1.100 * 2^(63+56)
movl rRshf = 0x43e8000000000000 // 1.10000 2^63 for rshift
}
;;
{ .mfi
setf.exp f2TOM56 = rExp_2tom56 // form 2^-56 for scaling Nfloat
fclass.m p9,p0 = f8,0x22 // Test for x=-inf
add rAD_TB2 = 0x140, rAD_TB1 // Point to Table 2
}
{ .mib
add rAD_Q1 = 0x1e0, rAD_TB1 // Point to Q table for small path
add rAD_Ln2_lo = 0x30, rAD_TB1 // Point to ln2_by_128_lo
(p6) br.cond.spnt EXPM1_UNORM // Branch if x unorm
}
;;
EXPM1_COMMON:
{ .mfi
ldfpd fMIN_DBL_OFLOW_ARG, fMAX_DBL_MINUS_1_ARG = [rAD_TB1],16
fclass.m p10,p0 = f8,0x1e1 // Test for x=+inf, NaN, NaT
add rAD_Q2 = 0x50, rAD_Q1 // Point to Q table for small path
}
{ .mfb
nop.m 0
nop.f 0
(p8) br.ret.spnt b0 // Exit for x=0, return x
}
;;
{ .mfi
ldfd fMAX_DBL_NORM_ARG = [rAD_TB1],16
nop.f 0
and rExp_x = rExp_mask, rSignexp_x // Biased exponent of x
}
{ .mfb
setf.d fRSHF = rRshf // Form right shift const 1.100 * 2^63
(p9) fms.d.s0 f8 = f0,f0,f1 // quick exit for x=-inf
(p9) br.ret.spnt b0
}
;;
{ .mfi
ldfpd fQD, fQC = [rAD_Q1], 16 // Load coeff for small path
nop.f 0
sub rExp_x = rExp_x, rExp_bias // True exponent of x
}
{ .mfb
ldfpd fQB, fQA = [rAD_Q2], 16 // Load coeff for small path
(p10) fma.d.s0 f8 = f8, f1, f0 // For x=+inf, NaN, NaT
(p10) br.ret.spnt b0 // Exit for x=+inf, NaN, NaT
}
;;
{ .mfi
ldfpd fQ9, fQ8 = [rAD_Q1], 16 // Load coeff for small path
fma.s1 fXsq = fNormX, fNormX, f0 // x*x for small path
cmp.gt p7, p8 = -2, rExp_x // Test |x| < 2^(-2)
}
{ .mfi
ldfpd fQ7, fQ6 = [rAD_Q2], 16 // Load coeff for small path
nop.f 0
nop.i 0
}
;;
{ .mfi
ldfe fQ5 = [rAD_Q1], 16 // Load coeff for small path
nop.f 0
nop.i 0
}
{ .mib
ldfe fQ4 = [rAD_Q2], 16 // Load coeff for small path
(p7) cmp.gt.unc p6, p7 = -60, rExp_x // Test |x| < 2^(-60)
(p7) br.cond.spnt EXPM1_SMALL // Branch if 2^-60 <= |x| < 2^-2
}
;;
// 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
ldfe fLn2_by_128_hi = [rAD_TB1],32
fma.s1 fW_2TO56_RSH = fNormX, fINV_LN2_2TO63, fRSHF_2TO56
nop.i 0
}
{ .mfb
ldfe fLn2_by_128_lo = [rAD_Ln2_lo]
(p6) fma.d.s0 f8 = f8, f8, f8 // If x < 2^-60, result=x+x*x
(p6) br.ret.spnt b0 // Exit if x < 2^-60
}
;;
// Divide arguments into the following categories:
// Certain minus one p11 - -inf < x <= MAX_DBL_MINUS_1_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.
//
// After that last load, rAD_TB1 points to the beginning of table 1
{ .mfi
nop.m 0
fcmp.ge.s1 p15,p14 = fNormX,fMIN_DBL_OFLOW_ARG
nop.i 0
}
;;
{ .mfi
add rAD_P = 0x80, rAD_TB2
fcmp.le.s1 p11,p0 = fNormX,fMAX_DBL_MINUS_1_ARG
nop.i 0
}
;;
{ .mfb
ldfpd fP5, fP4 = [rAD_P] ,16
(p14) fcmp.gt.unc.s1 p14,p0 = fNormX,fMAX_DBL_NORM_ARG
(p15) br.cond.spnt EXPM1_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 EXPM1_CERTAIN_MINUS_ONE
}
;;
{ .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
// 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
// Load T1 and T2
{ .mmi
setf.exp f2M = rBiased_M
ldfe fT2 = [rAD_T2]
nop.i 0
}
;;
{ .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 fP54 = fR, fP5, fP4
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fP32 = fR, fP3, fP2
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fRsq = fR, fR, f0
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fP5432 = fRsq, fP54, fP32
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fS2 = fF,fT2,f0
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fS1 = f2M,fT1,f0
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fP = fRsq, fP5432, fR
nop.i 0
}
;;
{ .mfi
nop.m 0
fms.s1 fSm1 = fS1,fS2,f1 // S - 1.0
nop.i 0
}
{ .mfb
nop.m 0
fma.s1 fS = fS1,fS2,f0
(p14) br.cond.spnt EXPM1_POSSIBLE_OVERFLOW
}
;;
{ .mfb
nop.m 0
fma.d.s0 f8 = fS, fP, fSm1
br.ret.sptk b0 // Normal path exit
}
;;
// Here if 2^-60 <= |x| <2^-2
// Compute 13th order polynomial
EXPM1_SMALL:
{ .mmf
ldfe fQ3 = [rAD_Q1], 16
ldfe fQ2 = [rAD_Q2], 16
fma.s1 fX4 = fXsq, fXsq, f0
}
;;
{ .mfi
nop.m 0
fma.s1 fQDC = fQD, fNormX, fQC
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fQBA = fQB, fNormX, fQA
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fQ98 = fQ9, fNormX, fQ8
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fQ76= fQ7, fNormX, fQ6
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fQ54 = fQ5, fNormX, fQ4
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fX6 = fX4, fXsq, f0
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fQ32= fQ3, fNormX, fQ2
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fQDCBA = fQDC, fXsq, fQBA
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fQ7654 = fQ76, fXsq, fQ54
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fQDCBA98 = fQDCBA, fXsq, fQ98
nop.i 0
}
{ .mfi
nop.m 0
fma.s1 fQ765432 = fQ7654, fXsq, fQ32
nop.i 0
}
;;
{ .mfi
nop.m 0
fma.s1 fQDCBA98765432 = fQDCBA98, fX6, fQ765432
nop.i 0
}
;;
{ .mfb
nop.m 0
fma.d.s0 f8 = fQDCBA98765432, fXsq, fNormX
br.ret.sptk b0 // Exit small branch
}
;;
EXPM1_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, fSm1 // 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 EXPM1_CERTAIN_OVERFLOW // Branch if overflow
}
;;
{ .mfb
nop.m 0
fma.d.s0 f8 = fS, fP, fSm1
br.ret.sptk b0 // Exit if really no overflow
}
;;
EXPM1_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 = 41
fma.d.s0 FR_RESULT = fTmp, fTmp, f0 // Set I,O and +INF result
br.cond.sptk __libm_error_region
}
;;
// Here if x unorm
EXPM1_UNORM:
{ .mfb
getf.exp rSignexp_x = fNormX // Must recompute if x unorm
fcmp.eq.s0 p6, p0 = f8, f0 // Set D flag
br.cond.sptk EXPM1_COMMON
}
;;
// here if result will be -1 and inexact, x <= -48.0
EXPM1_CERTAIN_MINUS_ONE:
{ .mmi
mov rTmp = 1
;;
setf.exp fTmp = rTmp
nop.i 0
}
;;
{ .mfb
nop.m 0
fms.d.s0 FR_RESULT = fTmp, fTmp, f1 // Set I, rounded -1+eps result
br.ret.sptk b0
}
;;
GLOBAL_IEEE754_END(expm1)
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#