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-rw-r--r--sysdeps/ia64/fpu/e_expf.S957
1 files changed, 511 insertions, 446 deletions
diff --git a/sysdeps/ia64/fpu/e_expf.S b/sysdeps/ia64/fpu/e_expf.S
index 6fe0a833e2..2aad021335 100644
--- a/sysdeps/ia64/fpu/e_expf.S
+++ b/sysdeps/ia64/fpu/e_expf.S
@@ -1,10 +1,10 @@
.file "expf.s"
-
-// Copyright (c) 2000 - 2005, Intel Corporation
+// Copyright (C) 2000, 2001, Intel Corporation
// All rights reserved.
//
-// Contributed 2000 by the Intel Numerics Group, Intel Corporation
+// Contributed 2/2/2000 by John Harrison, Ted Kubaska, Bob Norin, Shane Story,
+// and Ping Tak Peter Tang of the Computational Software Lab, Intel Corporation.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
@@ -20,7 +20,7 @@
// * 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
@@ -35,503 +35,589 @@
//
// 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.
+// http://developer.intel.com/opensource.
// History
-//*********************************************************************
-// 02/02/00 Original version
-// 04/04/00 Unwind support added
-// 08/15/00 Bundle added after call to __libm_error_support to properly
+//==============================================================
+// 4/04/00 Unwind update
+// 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.
-// 08/21/00 Improvements to save 2 cycles on main path, and shorten x=0 case
+// 8/21/00 Improvements to save 2 cycles on main path, and shorten x=0 case
// 12/07/00 Widen main path, shorten x=inf, nan paths
-// 03/15/01 Fix monotonicity problem around x=0 for round to +inf
-// 02/05/02 Corrected uninitialize predicate in POSSIBLE_UNDERFLOW path
-// 05/20/02 Cleaned up namespace and sf0 syntax
-// 07/26/02 Algorithm changed, accuracy improved
-// 09/26/02 support of higher precision inputs added, underflow threshold
-// corrected
-// 11/15/02 Improved performance on Itanium 2, added possible over/under paths
-// 05/30/03 Set inexact flag on unmasked overflow/underflow
-// 03/31/05 Reformatted delimiters between data tables
-//
-//
-// API
-//*********************************************************************
-// float expf(float)
-//
-// Overview of operation
-//*********************************************************************
-// Take the input x. w is "how many log2/128 in x?"
-// w = x * 64/log2
-// NJ = int(w)
-// x = NJ*log2/64 + R
-
-// NJ = 64*n + j
-// x = n*log2 + (log2/64)*j + R
-//
-// So, exp(x) = 2^n * 2^(j/64)* exp(R)
-//
-// T = 2^n * 2^(j/64)
-// Construct 2^n
-// Get 2^(j/64) table
-// actually all the entries of 2^(j/64) table are stored in DP and
-// with exponent bits set to 0 -> multiplication on 2^n can be
-// performed by doing logical "or" operation with bits presenting 2^n
-
-// exp(R) = 1 + (exp(R) - 1)
-// P = exp(R) - 1 approximated by Taylor series of 3rd degree
-// P = A3*R^3 + A2*R^2 + R, A3 = 1/6, A2 = 1/2
//
-// The final result is reconstructed as follows
-// exp(x) = T + T*P
+#include "libm_support.h"
-// Special values
-//*********************************************************************
-// expf(+0) = 1.0
-// expf(-0) = 1.0
+// Assembly macros
+//==============================================================
+// integer registers used
-// expf(+qnan) = +qnan
-// expf(-qnan) = -qnan
-// expf(+snan) = +qnan
-// expf(-snan) = -qnan
+ exp_GR_0x0f = r33
+ exp_GR_0xf0 = r34
-// expf(-inf) = +0
-// expf(+inf) = +inf
+ EXP_AD_P_1 = r36
+ EXP_AD_P_2 = r37
+ EXP_AD_T1 = r38
+ EXP_AD_T2 = r39
+ exp_GR_Mint = r40
-// Overflow and Underflow
-//*********************************************************************
-// expf(x) = largest single normal when
-// x = 88.72283 = 0x42b17217
+ exp_GR_Mint_p_128 = r41
+ exp_GR_Ind1 = r42
+ EXP_AD_M1 = r43
+ exp_GR_Ind2 = r44
+ EXP_AD_M2 = r45
-// expf(x) = smallest single normal when
-// x = -87.33654 = 0xc2aeac4f
+ exp_GR_min_oflow = r46
+ exp_GR_max_zero = r47
+ exp_GR_max_norm = r48
+ exp_GR_max_uflow = r49
+ exp_GR_min_norm = r50
-// expf(x) = largest round-to-nearest single zero when
-// x = -103.97208 = 0xc2cff1b5
+ exp_GR_17ones = r51
+ exp_GR_gt_ln = r52
+ exp_GR_T2_size = r53
+ exp_GR_17ones_m1 = r56
+ exp_GR_one = r57
-// Registers used
-//*********************************************************************
-// Floating Point registers used:
-// f8, input
-// f6,f7, f9 -> f15, f32 -> f40
-// General registers used:
-// r3, r23 -> r38
-// Predicate registers used:
-// p10 -> p15
+GR_SAVE_B0 = r53
+GR_SAVE_PFS = r55
+GR_SAVE_GP = r54
+
+GR_Parameter_X = r59
+GR_Parameter_Y = r60
+GR_Parameter_RESULT = r61
+GR_Parameter_TAG = r62
+
+FR_X = f10
+FR_Y = f1
+FR_RESULT = f8
-// Assembly macros
-//*********************************************************************
-// integer registers used
-// scratch
-rNJ = r3
-
-rTmp = r23
-rJ = r23
-rN = r24
-rTblAddr = r25
-rA3 = r26
-rExpHalf = r27
-rLn2Div64 = r28
-r17ones_m1 = r29
-rGt_ln = r29
-rRightShifter = r30
-r64DivLn2 = 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
-fRightShifter = f6
-f64DivLn2 = f7
-fNormX = f9
-fNint = f10
-fN = f11
-fR = f12
-fLn2Div64 = f13
-fA2 = f14
-fA3 = f15
-// stacked
-fP = f32
-fT = f33
-fMIN_SGL_OFLOW_ARG = f34
-fMAX_SGL_ZERO_ARG = f35
-fMAX_SGL_NORM_ARG = f36
-fMIN_SGL_NORM_ARG = f37
-fRSqr = f38
-fTmp = f39
-fGt_pln = f39
-fWre_urm_f8 = f40
-fFtz_urm_f8 = f40
-
-
-RODATA
+
+ EXP_MIN_SGL_OFLOW_ARG = f11
+ EXP_MAX_SGL_ZERO_ARG = f12
+ EXP_MAX_SGL_NORM_ARG = f13
+ EXP_MAX_SGL_UFLOW_ARG = f14
+ EXP_MIN_SGL_NORM_ARG = f15
+
+ exp_coeff_P5 = f32
+ exp_coeff_P6 = f33
+ exp_coeff_P3 = f34
+ exp_coeff_P4 = f35
+
+ exp_coeff_P1 = f36
+ exp_coeff_P2 = f37
+ exp_Mx = f38
+ exp_Mfloat = f39
+ exp_R = f40
+
+ exp_P1 = f41
+ exp_P2 = f42
+ exp_P3 = f43
+ exp_Rsq = f44
+ exp_R4 = f45
+
+ exp_P4 = f46
+ exp_P5 = f47
+ exp_P6 = f48
+ exp_P7 = f49
+ exp_T1 = f50
+
+ exp_T2 = f51
+ exp_T = f52
+ exp_A = f53
+ exp_norm_f8 = f54
+ exp_wre_urm_f8 = f55
+
+ exp_ftz_urm_f8 = f56
+ exp_gt_pln = f57
+
+
+#ifdef _LIBC
+.rodata
+#else
+.data
+#endif
+
.align 16
-LOCAL_OBJECT_START(_expf_table)
-data4 0x42b17218 // Smallest sgl arg to overflow sgl result, +88.7228
-data4 0xc2cff1b5 // Largest sgl for rnd-to-nearest 0 result, -103.9720
-data4 0x42b17217 // Largest sgl arg to give normal sgl result, +88.7228
-data4 0xc2aeac4f // Smallest sgl arg to give normal sgl result, -87.3365
+exp_coeff_1_table:
+ASM_TYPE_DIRECTIVE(exp_coeff_1_table,@object)
+data8 0x3F56F35FDE4F8563 // p5
+data8 0x3F2A378BEFECCFDD // p6
+data8 0x3FE00000258C581D // p1
+data8 0x3FC555557AE7B3D4 // p2
+ASM_SIZE_DIRECTIVE(exp_coeff_1_table)
+
+
+exp_coeff_2_table:
+ASM_TYPE_DIRECTIVE(exp_coeff_2_table,@object)
+data8 0x3FA5551BB6592FAE // p3
+data8 0x3F8110E8EBFFD485 // p4
+ASM_SIZE_DIRECTIVE(exp_coeff_2_table)
+
+
+exp_T2_table:
+ASM_TYPE_DIRECTIVE(exp_T2_table,@object)
+data8 0xa175cf9cd7d85844 , 0x00003f46 // exp(-128)
+data8 0xdb7279415a1f9eed , 0x00003f47 // exp(-127)
+data8 0x95213b242bd8ca5f , 0x00003f49 // exp(-126)
+data8 0xcab03c968c989f83 , 0x00003f4a // exp(-125)
+data8 0x89bdb674702961ad , 0x00003f4c // exp(-124)
+data8 0xbb35a2eec278be35 , 0x00003f4d // exp(-123)
+data8 0xfe71b17f373e7e7a , 0x00003f4e // exp(-122)
+data8 0xace9a6ec52a39b63 , 0x00003f50 // exp(-121)
+data8 0xeb03423fe393cf1c , 0x00003f51 // exp(-120)
+data8 0x9fb52c5bcaef1693 , 0x00003f53 // exp(-119)
+data8 0xd910b6377ed60bf1 , 0x00003f54 // exp(-118)
+data8 0x9382dad8a9fdbfe4 , 0x00003f56 // exp(-117)
+data8 0xc87d0a84dea869a3 , 0x00003f57 // exp(-116)
+data8 0x883efb4c6d1087b0 , 0x00003f59 // exp(-115)
+data8 0xb92d7373dce9a502 , 0x00003f5a // exp(-114)
+data8 0xfbaeb020577fb0cb , 0x00003f5b // exp(-113)
+ASM_SIZE_DIRECTIVE(exp_T2_table)
+
+
+exp_T1_table:
+ASM_TYPE_DIRECTIVE(exp_T1_table,@object)
+data8 0x8000000000000000 , 0x00003fff // exp(16 * 0)
+data8 0x87975e8540010249 , 0x00004016 // exp(16 * 1)
+data8 0x8fa1fe625b3163ec , 0x0000402d // exp(16 * 2)
+data8 0x9826b576512a59d7 , 0x00004044 // exp(16 * 3)
+data8 0xa12cc167acbe6902 , 0x0000405b // exp(16 * 4)
+data8 0xaabbcdcc279f59e4 , 0x00004072 // exp(16 * 5)
+data8 0xb4dbfaadc045d16f , 0x00004089 // exp(16 * 6)
+data8 0xbf95e372ccdbf146 , 0x000040a0 // exp(16 * 7)
+data8 0xcaf2a62eea10bbfb , 0x000040b7 // exp(16 * 8)
+data8 0xd6fbeb62fddbd340 , 0x000040ce // exp(16 * 9)
+data8 0xe3bbee32e4a440ea , 0x000040e5 // exp(16 * 10)
+data8 0xf13d8517c34199a8 , 0x000040fc // exp(16 * 11)
+data8 0xff8c2b166241eedd , 0x00004113 // exp(16 * 12)
+data8 0x875a04c0b38d6129 , 0x0000412b // exp(16 * 13)
+data8 0x8f610127db6774d7 , 0x00004142 // exp(16 * 14)
+data8 0x97e1dd87e5c20bb6 , 0x00004159 // exp(16 * 15)
+ASM_SIZE_DIRECTIVE(exp_T1_table)
+
+// Argument Reduction
+// exp_Mx = (int)f8 ==> The value of f8 rounded to int is placed into the
+// significand of exp_Mx as a two's
+// complement number.
+
+// Later we want to have exp_Mx in a general register. Do this with a getf.sig
+// and call the general register exp_GR_Mint
+
+// exp_Mfloat = (float)(int)f8 ==> the two's complement number in
+// significand of exp_Mx is turned
+// into a floating point number.
+// R = 1 - exp_Mfloat ==> reduced argument
+
+// Core Approximation
+// Calculate a series in R
+// R * p6 + p5
+// R * p4 + p3
+// R * p2 + p1
+// R^2
+// R^4
+// R^2(R * p6 + p5) + (R * p4 + p3)
+// R^2(R * p2 + p1)
+// R^4(R^2(R * p6 + p5) + (R * p4 + p3)) + (R^2(R * p2 + p1))
+// R + 1
+// exp(R) = (1 + R) + R^4(R^2(R * p6 + p5) + (R * p4 + p3)) + (R^2(R * p2 + p1))
+// exp(R) = 1 + R + R^2 * p1 + R^3 * p2 + R^4 * p3 + R^5 * p4 + R^6 * p5 + R^7 * p6
+
+// Reconstruction
+// signficand of exp_Mx is two's complement,
+// -103 < x < 89
+// The smallest single denormal is 2^-149 = ssdn
+// For e^x = ssdn
+// x = log(ssdn) = -103.279
+// But with rounding result goes to ssdn until -103.972079
+// The largest single normal is 1.<23 1's> 2^126 ~ 2^127 = lsn
+// For e^x = lsn
+// x = log(lsn) = 88.7228
//
-// 2^(j/64) table, j goes from 0 to 63
-data8 0x0000000000000000 // 2^(0/64)
-data8 0x00002C9A3E778061 // 2^(1/64)
-data8 0x000059B0D3158574 // 2^(2/64)
-data8 0x0000874518759BC8 // 2^(3/64)
-data8 0x0000B5586CF9890F // 2^(4/64)
-data8 0x0000E3EC32D3D1A2 // 2^(5/64)
-data8 0x00011301D0125B51 // 2^(6/64)
-data8 0x0001429AAEA92DE0 // 2^(7/64)
-data8 0x000172B83C7D517B // 2^(8/64)
-data8 0x0001A35BEB6FCB75 // 2^(9/64)
-data8 0x0001D4873168B9AA // 2^(10/64)
-data8 0x0002063B88628CD6 // 2^(11/64)
-data8 0x0002387A6E756238 // 2^(12/64)
-data8 0x00026B4565E27CDD // 2^(13/64)
-data8 0x00029E9DF51FDEE1 // 2^(14/64)
-data8 0x0002D285A6E4030B // 2^(15/64)
-data8 0x000306FE0A31B715 // 2^(16/64)
-data8 0x00033C08B26416FF // 2^(17/64)
-data8 0x000371A7373AA9CB // 2^(18/64)
-data8 0x0003A7DB34E59FF7 // 2^(19/64)
-data8 0x0003DEA64C123422 // 2^(20/64)
-data8 0x0004160A21F72E2A // 2^(21/64)
-data8 0x00044E086061892D // 2^(22/64)
-data8 0x000486A2B5C13CD0 // 2^(23/64)
-data8 0x0004BFDAD5362A27 // 2^(24/64)
-data8 0x0004F9B2769D2CA7 // 2^(25/64)
-data8 0x0005342B569D4F82 // 2^(26/64)
-data8 0x00056F4736B527DA // 2^(27/64)
-data8 0x0005AB07DD485429 // 2^(28/64)
-data8 0x0005E76F15AD2148 // 2^(29/64)
-data8 0x0006247EB03A5585 // 2^(30/64)
-data8 0x0006623882552225 // 2^(31/64)
-data8 0x0006A09E667F3BCD // 2^(32/64)
-data8 0x0006DFB23C651A2F // 2^(33/64)
-data8 0x00071F75E8EC5F74 // 2^(34/64)
-data8 0x00075FEB564267C9 // 2^(35/64)
-data8 0x0007A11473EB0187 // 2^(36/64)
-data8 0x0007E2F336CF4E62 // 2^(37/64)
-data8 0x00082589994CCE13 // 2^(38/64)
-data8 0x000868D99B4492ED // 2^(39/64)
-data8 0x0008ACE5422AA0DB // 2^(40/64)
-data8 0x0008F1AE99157736 // 2^(41/64)
-data8 0x00093737B0CDC5E5 // 2^(42/64)
-data8 0x00097D829FDE4E50 // 2^(43/64)
-data8 0x0009C49182A3F090 // 2^(44/64)
-data8 0x000A0C667B5DE565 // 2^(45/64)
-data8 0x000A5503B23E255D // 2^(46/64)
-data8 0x000A9E6B5579FDBF // 2^(47/64)
-data8 0x000AE89F995AD3AD // 2^(48/64)
-data8 0x000B33A2B84F15FB // 2^(49/64)
-data8 0x000B7F76F2FB5E47 // 2^(50/64)
-data8 0x000BCC1E904BC1D2 // 2^(51/64)
-data8 0x000C199BDD85529C // 2^(52/64)
-data8 0x000C67F12E57D14B // 2^(53/64)
-data8 0x000CB720DCEF9069 // 2^(54/64)
-data8 0x000D072D4A07897C // 2^(55/64)
-data8 0x000D5818DCFBA487 // 2^(56/64)
-data8 0x000DA9E603DB3285 // 2^(57/64)
-data8 0x000DFC97337B9B5F // 2^(58/64)
-data8 0x000E502EE78B3FF6 // 2^(59/64)
-data8 0x000EA4AFA2A490DA // 2^(60/64)
-data8 0x000EFA1BEE615A27 // 2^(61/64)
-data8 0x000F50765B6E4540 // 2^(62/64)
-data8 0x000FA7C1819E90D8 // 2^(63/64)
-LOCAL_OBJECT_END(_expf_table)
+// expf overflows when x > 42b17218 = 88.7228
+// expf returns largest single denormal when x = c2aeac50
+// expf goes to zero when x < c2cff1b5
+
+// Consider range of 8-bit two's complement, -128 ---> 127
+// Add 128; range becomes 0 ---> 255
+
+// The number (=i) in 0 ---> 255 is used as offset into two tables.
+// i = abcd efgh = abcd * 16 + efgh = i1 * 16 + i2
+
+// i1 = (exp_GR_Mint + 128) & 0xf0 (show 0xf0 as -0x10 to avoid assembler error)
+// (The immediate in the AND is an 8-bit two's complement)
+// i1 = i1 + start of T1 table (EXP_AD_T1)
+// Note that the entries in T1 are double-extended numbers on 16-byte boundaries
+// and that i1 is already shifted left by 16 after the AND.
+
+// i2 must be shifted left by 4 before adding to the start of the table.
+// i2 = ((exp_GR_Mint + 128) & 0x0f) << 4
+// i2 = i2 + start of T2 table (EXP_AD_T2)
+
+// T = T1 * T2
+// A = T * (1 + R)
+// answer = T * (R^2 * p1 + R^3 * p2 + R^4 * p3 + R^5 * p4 + R^6 * p5 + R^7 * p6) +
+// T * (1 + R)
+// = T * exp(R)
+
+
+.global expf#
.section .text
-GLOBAL_IEEE754_ENTRY(expf)
-
-{ .mlx
- addl rTblAddr = @ltoff(_expf_table),gp
- movl r64DivLn2 = 0x40571547652B82FE // 64/ln(2)
+.proc expf#
+.align 32
+expf:
+#ifdef _LIBC
+.global __ieee754_expf#
+__ieee754_expf:
+#endif
+
+{ .mfi
+ alloc r32 = ar.pfs,1,26,4,0
+ fcvt.fx.s1 exp_Mx = f8
+ mov exp_GR_17ones = 0x1FFFF
}
{ .mlx
- addl rA3 = 0x3E2AA, r0 // high bits of 1.0/6.0 rounded to SP
- movl rRightShifter = 0x43E8000000000000 // DP Right Shifter
+ addl EXP_AD_P_1 = @ltoff(exp_coeff_1_table),gp
+ movl exp_GR_min_oflow = 0x42b17218
}
;;
+// Fnorm done to take any enabled faults
{ .mfi
- // point to the beginning of the table
- ld8 rTblAddr = [rTblAddr]
- fclass.m p14, p0 = f8, 0x22 // test for -INF
- shl rA3 = rA3, 12 // 0x3E2AA000, approx to 1.0/6.0 in SP
+ ld8 EXP_AD_P_1 = [EXP_AD_P_1]
+ fclass.m p6,p0 = f8, 0x07 //@zero
+ nop.i 999
}
{ .mfi
- nop.m 0
- fnorm.s1 fNormX = f8 // normalized x
- addl rExpHalf = 0xFFFE, r0 // exponent of 1/2
+ add exp_GR_max_norm = -1, exp_GR_min_oflow // 0x42b17217
+ fnorm exp_norm_f8 = f8
+ nop.i 999
}
;;
{ .mfi
- setf.d f64DivLn2 = r64DivLn2 // load 64/ln(2) to FP reg
- fclass.m p15, p0 = f8, 0x1e1 // test for NaT,NaN,+Inf
- nop.i 0
+ setf.s EXP_MIN_SGL_OFLOW_ARG = exp_GR_min_oflow // 0x42b17218
+ fclass.m p7,p0 = f8, 0x22 // Test for x=-inf
+ mov exp_GR_0xf0 = 0x0f0
}
{ .mlx
- // load Right Shifter to FP reg
- setf.d fRightShifter = rRightShifter
- movl rLn2Div64 = 0x3F862E42FEFA39EF // DP ln(2)/64 in GR
+ setf.s EXP_MAX_SGL_NORM_ARG = exp_GR_max_norm
+ movl exp_GR_max_zero = 0xc2cff1b5
}
;;
-{ .mfi
- nop.m 0
- fcmp.eq.s1 p13, p0 = f0, f8 // test for x = 0.0
- nop.i 0
+
+{ .mlx
+ mov exp_GR_0x0f = 0x00f
+ movl exp_GR_max_uflow = 0xc2aeac50
}
{ .mfb
- setf.s fA3 = rA3 // load A3 to FP reg
-(p14) fma.s.s0 f8 = f0, f1, f0 // result if x = -inf
-(p14) br.ret.spnt b0 // exit here if x = -inf
+ nop.m 999
+(p6) fma.s f8 = f1,f1,f0
+(p6) br.ret.spnt b0 // quick exit for x=0
}
;;
{ .mfi
- setf.exp fA2 = rExpHalf // load A2 to FP reg
- fcmp.eq.s0 p6, p0 = f8, f0 // Dummy to flag denorm
- nop.i 0
+ setf.s EXP_MAX_SGL_ZERO_ARG = exp_GR_max_zero
+ fclass.m p8,p0 = f8, 0x21 // Test for x=+inf
+ adds exp_GR_min_norm = 1, exp_GR_max_uflow // 0xc2aeac51
}
{ .mfb
- setf.d fLn2Div64 = rLn2Div64 // load ln(2)/64 to FP reg
-(p15) fma.s.s0 f8 = f8, f1, f0 // result if x = NaT,NaN,+Inf
-(p15) br.ret.spnt b0 // exit here if x = NaT,NaN,+Inf
+ ldfpd exp_coeff_P5,exp_coeff_P6 = [EXP_AD_P_1],16
+(p7) fma.s f8 = f0,f0,f0
+(p7) br.ret.spnt b0 // quick exit for x=-inf
}
;;
-{ .mfb
- // overflow and underflow_zero threshold
- ldfps fMIN_SGL_OFLOW_ARG, fMAX_SGL_ZERO_ARG = [rTblAddr], 8
-(p13) fma.s.s0 f8 = f1, f1, f0 // result if x = 0.0
-(p13) br.ret.spnt b0 // exit here if x =0.0
+{ .mmf
+ ldfpd exp_coeff_P1,exp_coeff_P2 = [EXP_AD_P_1],16
+ setf.s EXP_MAX_SGL_UFLOW_ARG = exp_GR_max_uflow
+ fclass.m p9,p0 = f8, 0xc3 // Test for x=nan
}
;;
- // max normal and underflow_denorm threshold
-{ .mfi
- ldfps fMAX_SGL_NORM_ARG, fMIN_SGL_NORM_ARG = [rTblAddr], 8
- nop.f 0
- nop.i 0
+{ .mmb
+ ldfpd exp_coeff_P3,exp_coeff_P4 = [EXP_AD_P_1],16
+ setf.s EXP_MIN_SGL_NORM_ARG = exp_GR_min_norm
+(p8) br.ret.spnt b0 // quick exit for x=+inf
}
;;
+// EXP_AD_P_1 now points to exp_T2_table
{ .mfi
- nop.m 0
- // x*(64/ln(2)) + Right Shifter
- fma.s1 fNint = fNormX, f64DivLn2, fRightShifter
- nop.i 0
+ mov exp_GR_T2_size = 0x100
+ fcvt.xf exp_Mfloat = exp_Mx
+ nop.i 999
+}
+;;
+
+{ .mfb
+ getf.sig exp_GR_Mint = exp_Mx
+(p9) fmerge.s f8 = exp_norm_f8, exp_norm_f8
+(p9) br.ret.spnt b0 // quick exit for x=nan
}
;;
+{ .mmi
+ nop.m 999
+ mov EXP_AD_T2 = EXP_AD_P_1
+ add EXP_AD_T1 = exp_GR_T2_size,EXP_AD_P_1 ;;
+}
+
+
+{ .mmi
+ adds exp_GR_Mint_p_128 = 0x80,exp_GR_Mint ;;
+ and exp_GR_Ind1 = exp_GR_Mint_p_128, exp_GR_0xf0
+ and exp_GR_Ind2 = exp_GR_Mint_p_128, exp_GR_0x0f ;;
+}
+
// Divide arguments into the following categories:
-// Certain Underflow p11 - -inf < x <= MAX_SGL_ZERO_ARG
-// Possible Underflow p13 - MAX_SGL_ZERO_ARG < x < MIN_SGL_NORM_ARG
+// Certain Underflow/zero p11 - -inf < x <= MAX_SGL_ZERO_ARG
+// Certain Underflow p12 - MAX_SGL_ZERO_ARG < x <= MAX_SGL_UFLOW_ARG
+// Possible Underflow p13 - MAX_SGL_UFLOW_ARG < x < MIN_SGL_NORM_ARG
// Certain Safe - MIN_SGL_NORM_ARG <= x <= MAX_SGL_NORM_ARG
// Possible Overflow p14 - MAX_SGL_NORM_ARG < x < MIN_SGL_OFLOW_ARG
// Certain Overflow p15 - MIN_SGL_OFLOW_ARG <= x < +inf
//
-// If the input is really a single arg, then there will never be
-// "Possible Overflow" arguments.
+// If the input is really a single arg, then there will never be "Possible
+// Underflow" or "Possible Overflow" arguments.
//
{ .mfi
- nop.m 0
- // check for overflow
- fcmp.ge.s1 p15, p0 = fNormX, fMIN_SGL_OFLOW_ARG
- nop.i 0
+ add EXP_AD_M1 = exp_GR_Ind1,EXP_AD_T1
+ fcmp.ge.s1 p15,p14 = exp_norm_f8,EXP_MIN_SGL_OFLOW_ARG
+ nop.i 999
+}
+{ .mfi
+ shladd EXP_AD_M2 = exp_GR_Ind2,4,EXP_AD_T2
+ fms.s1 exp_R = f1,f8,exp_Mfloat
+ nop.i 999 ;;
}
-;;
{ .mfi
- nop.m 0
- // check for underflow and tiny (+0) result
- fcmp.le.s1 p11, p0 = fNormX, fMAX_SGL_ZERO_ARG
- nop.i 0
+ ldfe exp_T1 = [EXP_AD_M1]
+ fcmp.le.s1 p11,p12 = exp_norm_f8,EXP_MAX_SGL_ZERO_ARG
+ nop.i 999 ;;
}
+
{ .mfb
- nop.m 0
- fms.s1 fN = fNint, f1, fRightShifter // n in FP register
- // branch out if overflow
-(p15) br.cond.spnt EXP_CERTAIN_OVERFLOW
+ ldfe exp_T2 = [EXP_AD_M2]
+(p14) fcmp.gt.s1 p14,p0 = exp_norm_f8,EXP_MAX_SGL_NORM_ARG
+(p15) br.cond.spnt L(EXP_CERTAIN_OVERFLOW) ;;
}
-;;
{ .mfb
- getf.sig rNJ = fNint // bits of n, j
- // check for underflow and deno result
- fcmp.lt.s1 p13, p0 = fNormX, fMIN_SGL_NORM_ARG
- // branch out if underflow and tiny (+0) result
-(p11) br.cond.spnt EXP_CERTAIN_UNDERFLOW
+ nop.m 999
+(p12) fcmp.le.s1 p12,p0 = exp_norm_f8,EXP_MAX_SGL_UFLOW_ARG
+(p11) br.cond.spnt L(EXP_CERTAIN_UNDERFLOW_ZERO)
}
;;
{ .mfi
- nop.m 0
- // check for possible overflow
- fcmp.gt.s1 p14, p0 = fNormX, fMAX_SGL_NORM_ARG
- extr.u rJ = rNJ, 0, 6 // bits of j
+ nop.m 999
+(p13) fcmp.lt.s1 p13,p0 = exp_norm_f8,EXP_MIN_SGL_NORM_ARG
+ nop.i 999
}
+;;
+
+
{ .mfi
- addl rN = 0xFFFF - 63, rNJ // biased and shifted n
- fnma.s1 fR = fLn2Div64, fN, fNormX // R = x - N*ln(2)/64
- nop.i 0
+ nop.m 999
+ fma.s1 exp_Rsq = exp_R,exp_R,f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 exp_P3 = exp_R,exp_coeff_P2,exp_coeff_P1
+ nop.i 999
}
;;
{ .mfi
- shladd rJ = rJ, 3, rTblAddr // address in the 2^(j/64) table
- nop.f 0
- shr rN = rN, 6 // biased n
+ nop.m 999
+ fma.s1 exp_P1 = exp_R,exp_coeff_P6,exp_coeff_P5
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 exp_P2 = exp_R,exp_coeff_P4,exp_coeff_P3
+ nop.i 999
}
;;
+
{ .mfi
- ld8 rJ = [rJ]
- nop.f 0
- shl rN = rN, 52 // 2^n bits in DP format
+ nop.m 999
+ fma.s1 exp_P7 = f1,exp_R,f1
+ nop.i 999
}
;;
+
{ .mfi
- or rN = rN, rJ // bits of 2^n * 2^(j/64) in DP format
- nop.f 0
- nop.i 0
+ nop.m 999
+ fma.s1 exp_P5 = exp_Rsq,exp_P3,f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 exp_R4 = exp_Rsq,exp_Rsq,f0
+ nop.i 999
}
;;
{ .mfi
- setf.d fT = rN // 2^n * 2^(j/64)
- fma.s1 fP = fA3, fR, fA2 // A3*R + A2
- nop.i 0
+ nop.m 999
+ fma.s1 exp_T = exp_T1,exp_T2,f0
+ nop.i 999
}
{ .mfi
- nop.m 0
- fma.s1 fRSqr = fR, fR, f0 // R^2
- nop.i 0
+ nop.m 999
+ fma.s1 exp_P4 = exp_Rsq,exp_P1,exp_P2
+ nop.i 999
}
;;
{ .mfi
- nop.m 0
- fma.s1 fP = fP, fRSqr, fR // P = (A3*R + A2)*R^2 + R
- nop.i 0
+ nop.m 999
+ fma.s1 exp_A = exp_T,exp_P7,f0
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+ fma.s1 exp_P6 = exp_R4,exp_P4,exp_P5
+ nop.i 999
}
;;
-{ .mbb
- nop.m 0
- // branch out if possible underflow
-(p13) br.cond.spnt EXP_POSSIBLE_UNDERFLOW
- // branch out if possible overflow result
-(p14) br.cond.spnt EXP_POSSIBLE_OVERFLOW
+{ .bbb
+(p12) br.cond.spnt L(EXP_CERTAIN_UNDERFLOW)
+(p13) br.cond.spnt L(EXP_POSSIBLE_UNDERFLOW)
+(p14) br.cond.spnt L(EXP_POSSIBLE_OVERFLOW)
}
;;
{ .mfb
- nop.m 0
- // final result in the absence of over- and underflow
- fma.s.s0 f8 = fP, fT, fT
- // exit here in the absence of over- and underflow
- br.ret.sptk b0
+ nop.m 999
+ fma.s f8 = exp_T,exp_P6,exp_A
+ br.ret.sptk b0
}
;;
-EXP_POSSIBLE_OVERFLOW:
+L(EXP_POSSIBLE_OVERFLOW):
+
+// We got an answer. EXP_MAX_SGL_NORM_ARG < x < EXP_MIN_SGL_OFLOW_ARG
+// overflow is a possibility, not a certainty
+// Set wre in s2 and perform the last operation with s2
+
+// We define an overflow when the answer with
+// WRE set
+// user-defined rounding mode
+// is lsn +1
+
+// Is the exponent 1 more than the largest single?
+// If so, go to ERROR RETURN, else (no overflow) get the answer and
+// leave.
+
+// Largest single is FE (biased single)
+// FE - 7F + FFFF = 1007E
+
+// Create + largest_single_plus_ulp
+// Create - largest_single_plus_ulp
-// Here if fMAX_SGL_NORM_ARG < x < fMIN_SGL_OFLOW_ARG
-// This cannot happen if input is a single, only if input higher precision.
-// Overflow is a possibility, not a certainty.
+// Calculate answer with WRE set.
-// Recompute result using status field 2 with user's rounding mode,
-// and wre set. If result is larger than largest single, then we have
-// overflow
+// Cases when answer is lsn+1 are as follows:
+
+// midpoint
+// |
+// lsn | lsn+1
+// --+----------|----------+------------
+// |
+// +inf +inf -inf
+// RN RN
+// RZ
+// exp_gt_pln contains the floating point number lsn+1.
+// The setf.exp puts 0x1007f in the exponent and 0x800... in the significand.
+
+// If the answer is >= lsn+1, we have overflowed.
+// Then p6 is TRUE. Set the overflow tag, save input in FR_X,
+// do the final calculation for IEEE result, and branch to error return.
{ .mfi
- mov rGt_ln = 0x1007f // Exponent for largest single + 1 ulp
- fsetc.s2 0x7F,0x42 // Get user's round mode, set wre
- nop.i 0
+ mov exp_GR_gt_ln = 0x1007F
+ fsetc.s2 0x7F,0x42
+ nop.i 999
}
;;
{ .mfi
- setf.exp fGt_pln = rGt_ln // Create largest single + 1 ulp
- fma.s.s2 fWre_urm_f8 = fP, fT, fT // Result with wre set
- nop.i 0
+ setf.exp exp_gt_pln = exp_GR_gt_ln
+ fma.s.s2 exp_wre_urm_f8 = exp_T, exp_P6, exp_A
+ nop.i 999
}
;;
{ .mfi
- nop.m 0
- fsetc.s2 0x7F,0x40 // Turn off wre in sf2
- nop.i 0
+ nop.m 999
+ fsetc.s2 0x7F,0x40
+ nop.i 999
}
;;
{ .mfi
- nop.m 0
- fcmp.ge.s1 p6, p0 = fWre_urm_f8, fGt_pln // Test for overflow
- nop.i 0
+ nop.m 999
+ fcmp.ge.unc.s1 p6, p0 = exp_wre_urm_f8, exp_gt_pln
+ nop.i 999
}
;;
{ .mfb
- nop.m 0
- nop.f 0
-(p6) br.cond.spnt EXP_CERTAIN_OVERFLOW // Branch if overflow
+ nop.m 999
+ nop.f 999
+(p6) br.cond.spnt L(EXP_CERTAIN_OVERFLOW) // Branch if really overflow
}
;;
{ .mfb
- nop.m 0
- fma.s.s0 f8 = fP, fT, fT
- br.ret.sptk b0 // Exit if really no overflow
+ nop.m 999
+ fma.s f8 = exp_T, exp_P6, exp_A
+ br.ret.sptk b0 // Exit if really no overflow
}
;;
-// here if overflow
-EXP_CERTAIN_OVERFLOW:
+L(EXP_CERTAIN_OVERFLOW):
{ .mmi
- addl r17ones_m1 = 0x1FFFE, r0
-;;
- setf.exp fTmp = r17ones_m1
- nop.i 0
+ sub exp_GR_17ones_m1 = exp_GR_17ones, r0, 1 ;;
+ setf.exp f9 = exp_GR_17ones_m1
+ nop.i 999 ;;
}
-;;
{ .mfi
- alloc r32=ar.pfs,0,3,4,0
- fmerge.s FR_X = f8,f8
- nop.i 0
+ nop.m 999
+ fmerge.s FR_X = f8,f8
+ nop.i 999
}
{ .mfb
- mov GR_Parameter_TAG = 16
- fma.s.s0 FR_RESULT = fTmp, fTmp, fTmp // Set I,O and +INF result
- br.cond.sptk __libm_error_region
+ mov GR_Parameter_TAG = 16
+ fma.s FR_RESULT = f9, f9, f0 // Set I,O and +INF result
+ br.cond.sptk __libm_error_region ;;
}
-;;
-EXP_POSSIBLE_UNDERFLOW:
+L(EXP_POSSIBLE_UNDERFLOW):
-// Here if fMAX_SGL_ZERO_ARG < x < fMIN_SGL_NORM_ARG
-// Underflow is a possibility, not a certainty
+// We got an answer. EXP_MAX_SGL_UFLOW_ARG < x < EXP_MIN_SGL_NORM_ARG
+// underflow is a possibility, not a certainty
// We define an underflow when the answer with
// ftz set
@@ -551,165 +637,144 @@ EXP_POSSIBLE_UNDERFLOW:
// E
// -----+--------------------+--------------------+-----
// | | |
-// 1.1...10 2^-3fff 1.1...11 2^-3fff 1.0...00 2^-3ffe
-// 0.1...11 2^-3ffe (biased, 1)
+// 1.1...10 2^-7f 1.1...11 2^-7f 1.0...00 2^-7e
+// 0.1...11 2^-7e (biased, 1)
// largest dn smallest normal
-{ .mfi
- nop.m 0
- fsetc.s2 0x7F,0x41 // Get user's round mode, set ftz
- nop.i 0
-}
-;;
+// If the answer is = 0, we have underflowed.
+// Then p6 is TRUE. Set the underflow tag, save input in FR_X,
+// do the final calculation for IEEE result, and branch to error return.
{ .mfi
- nop.m 0
- fma.s.s2 fFtz_urm_f8 = fP, fT, fT // Result with ftz set
- nop.i 0
+ nop.m 999
+ fsetc.s2 0x7F,0x41
+ nop.i 999
}
;;
{ .mfi
- nop.m 0
- fsetc.s2 0x7F,0x40 // Turn off ftz in sf2
- nop.i 0
+ nop.m 999
+ fma.s.s2 exp_ftz_urm_f8 = exp_T, exp_P6, exp_A
+ nop.i 999
}
;;
+
{ .mfi
- nop.m 0
- fcmp.eq.s1 p6, p7 = fFtz_urm_f8, f0 // Test for underflow
- nop.i 0
-}
-{ .mfi
- nop.m 0
- fma.s.s0 f8 = fP, fT, fT // Compute result, set I, maybe U
- nop.i 0
+ nop.m 999
+ fsetc.s2 0x7F,0x40
+ nop.i 999
}
;;
-{ .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
+{ .mfi
+ nop.m 999
+ fcmp.eq.unc.s1 p6, p0 = exp_ftz_urm_f8, f0
+ nop.i 999
}
;;
-EXP_CERTAIN_UNDERFLOW:
-// Here if x < fMAX_SGL_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
+{ .mfb
+ nop.m 999
+ nop.f 999
+(p6) br.cond.spnt L(EXP_CERTAIN_UNDERFLOW) // Branch if really underflow
}
;;
-{ .mfi
- nop.m 0
- fmerge.se fTmp = fTmp, f64DivLn2 // Small with non-trial signif
- nop.i 0
-}
-;;
-
{ .mfb
- nop.m 0
- fma.s.s0 f8 = fTmp, fTmp, f0 // Set I,U, tiny (+0.0) result
- br.cond.sptk EXP_UNDERFLOW_COMMON
+ nop.m 999
+ fma.s f8 = exp_T, exp_P6, exp_A
+ br.ret.sptk b0 // Exit if really no underflow
}
;;
-EXP_UNDERFLOW_COMMON:
-// Determine if underflow result is zero or nonzero
+L(EXP_CERTAIN_UNDERFLOW):
{ .mfi
- alloc r32=ar.pfs,0,3,4,0
- fcmp.eq.s1 p6, p0 = f8, f0
- nop.i 0
+ nop.m 999
+ fmerge.s FR_X = f8,f8
+ nop.i 999
}
-;;
-
{ .mfb
- nop.m 0
- fmerge.s FR_X = fNormX,fNormX
-(p6) br.cond.spnt EXP_UNDERFLOW_ZERO
+ mov GR_Parameter_TAG = 17
+ fma.s FR_RESULT = exp_T, exp_P6, exp_A // Set I,U and tiny result
+ br.cond.sptk __libm_error_region ;;
}
-;;
-EXP_UNDERFLOW_NONZERO:
-// Here if x < fMIN_SGL_NORM_ARG and result nonzero;
-// I, U are set
-{ .mfb
- mov GR_Parameter_TAG = 17
- nop.f 0 // FR_RESULT already set
- br.cond.sptk __libm_error_region
+L(EXP_CERTAIN_UNDERFLOW_ZERO):
+{ .mmi
+ mov exp_GR_one = 1 ;;
+ setf.exp f9 = exp_GR_one
+ nop.i 999 ;;
}
-;;
-EXP_UNDERFLOW_ZERO:
-// Here if x < fMIN_SGL_NORM_ARG and result zero;
-// I, U are set
+{ .mfi
+ nop.m 999
+ fmerge.s FR_X = f8,f8
+ nop.i 999
+}
{ .mfb
- mov GR_Parameter_TAG = 17
- nop.f 0 // FR_RESULT already set
- br.cond.sptk __libm_error_region
+ mov GR_Parameter_TAG = 17
+ fma.s FR_RESULT = f9, f9, f0 // Set I,U and tiny (+0.0) result
+ br.cond.sptk __libm_error_region ;;
}
-;;
-GLOBAL_IEEE754_END(expf)
+.endp expf
+ASM_SIZE_DIRECTIVE(expf)
-LOCAL_LIBM_ENTRY(__libm_error_region)
+.proc __libm_error_region
+__libm_error_region:
.prologue
{ .mfi
- add GR_Parameter_Y=-32,sp // Parameter 2 value
- nop.f 0
+ 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
+ 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
+ add sp=-64,sp // Create new stack
+ nop.f 0
+ mov GR_SAVE_GP=gp // Save gp
};;
{ .mmi
- stfs [GR_Parameter_Y] = FR_Y,16 // Store Parameter 2 on stack
- add GR_Parameter_X = 16,sp // Parameter 1 address
+ stfs [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
+ mov GR_SAVE_B0=b0 // Save b0
};;
.body
{ .mfi
- stfs [GR_Parameter_X] = FR_X // Store Parameter 1 on stack
- nop.f 0
- add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address
+ stfs [GR_Parameter_X] = FR_X // Store Parameter 1 on stack
+ nop.f 0
+ add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address
}
{ .mib
- stfs [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
+ stfs [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
+ nop.m 0
+ nop.m 0
+ add GR_Parameter_RESULT = 48,sp
};;
{ .mmi
- ldfs f8 = [GR_Parameter_RESULT] // Get return result off stack
+ ldfs 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
+ 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
-};;
+ 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)
+.endp __libm_error_region
+ASM_SIZE_DIRECTIVE(__libm_error_region)
.type __libm_error_support#,@function