mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 21:10:07 +00:00
451 lines
11 KiB
ArmAsm
451 lines
11 KiB
ArmAsm
.file "libm_scalblnf.s"
|
|
|
|
|
|
// Copyright (c) 2001 - 2003, Intel Corporation
|
|
// All rights reserved.
|
|
//
|
|
// Contributed 2001 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
|
|
//==============================================================
|
|
// 08/03/01 Initial version
|
|
// 08/23/01 Corrected error tag number
|
|
// 02/06/02 Corrected to handle 32- or 64-bit integers
|
|
// 05/20/02 Cleaned up namespace and sf0 syntax
|
|
// 02/10/03 Reordered header: .section, .global, .proc, .align
|
|
// 08/25/03 Improved performance
|
|
//
|
|
// API
|
|
//==============================================================
|
|
// float __libm_scalblnf (float x, long int n, int long_int_type)
|
|
// input floating point f8 and long int n (r33)
|
|
// input long_int_type = 0 if long int defined as 32 bits, = 1 if 64 bits
|
|
// output floating point f8
|
|
//
|
|
// Returns x* 2**n using an fma and detects overflow
|
|
// and underflow.
|
|
//
|
|
//
|
|
// Strategy:
|
|
// Compute biased exponent of result exp_Result = N + exp_X
|
|
// Break into ranges:
|
|
// exp_Result > 0x1007e -> Certain overflow
|
|
// exp_Result = 0x1007e -> Possible overflow
|
|
// 0x0ff81 <= exp_Result < 0x1007e -> No over/underflow (main path)
|
|
// 0x0ff81 - 23 <= exp_Result < 0x0ff81 -> Possible underflow
|
|
// exp_Result < 0x0ff81 - 23 -> Certain underflow
|
|
|
|
FR_Big = f6
|
|
FR_NBig = f7
|
|
FR_Floating_X = f8
|
|
FR_Result = f8
|
|
FR_Result2 = f9
|
|
FR_Result3 = f10
|
|
FR_Norm_X = f11
|
|
FR_Two_N = f12
|
|
|
|
GR_neg_ov_limit= r14
|
|
GR_N_Biased = r15
|
|
GR_Big = r16
|
|
GR_NBig = r17
|
|
GR_exp_Result = r18
|
|
GR_pos_ov_limit= r19
|
|
GR_Bias = r20
|
|
GR_N_as_int = r21
|
|
GR_signexp_X = r22
|
|
GR_exp_X = r23
|
|
GR_exp_mask = r24
|
|
GR_max_exp = r25
|
|
GR_min_exp = r26
|
|
GR_min_den_exp = r27
|
|
|
|
GR_SAVE_B0 = r32
|
|
GR_SAVE_GP = r33
|
|
GR_SAVE_PFS = r34
|
|
GR_Parameter_X = r35
|
|
GR_Parameter_Y = r36
|
|
GR_Parameter_RESULT = r37
|
|
GR_Tag = r38
|
|
|
|
.section .text
|
|
GLOBAL_LIBM_ENTRY(__libm_scalblnf)
|
|
|
|
//
|
|
// Is x NAN, INF, ZERO, +-?
|
|
// Build the exponent Bias
|
|
//
|
|
{ .mfi
|
|
getf.exp GR_signexp_X = FR_Floating_X // Get signexp of x
|
|
fclass.m p6,p0 = FR_Floating_X, 0xe7 // @snan | @qnan | @inf | @zero
|
|
mov GR_Bias = 0x0ffff
|
|
}
|
|
//
|
|
// Normalize x
|
|
// Is long integer type 32 bits?
|
|
//
|
|
{ .mfi
|
|
mov GR_Big = 35000 // If N this big then certain overflow
|
|
fnorm.s1 FR_Norm_X = FR_Floating_X
|
|
cmp.eq p8,p9 = r34,r0
|
|
}
|
|
;;
|
|
|
|
// Sign extend N if long int is 32 bits
|
|
{ .mfi
|
|
(p9) mov GR_N_as_int = r33 // Copy N if long int is 64 bits
|
|
fclass.m p9,p0 = FR_Floating_X, 0x0b // Test for x=unorm
|
|
(p8) sxt4 GR_N_as_int = r33 // Sign extend N if long int is 32 bits
|
|
}
|
|
{ .mfi
|
|
mov GR_NBig = -35000 // If N this small then certain underflow
|
|
nop.f 0
|
|
mov GR_max_exp = 0x1007e // Exponent of maximum float
|
|
}
|
|
;;
|
|
|
|
// Create biased exponent for 2**N
|
|
{ .mfi
|
|
add GR_N_Biased = GR_Bias,GR_N_as_int
|
|
nop.f 0
|
|
cmp.ge p7, p0 = GR_N_as_int, GR_Big // Certain overflow?
|
|
}
|
|
{ .mib
|
|
cmp.le p8, p0 = GR_N_as_int, GR_NBig // Certain underflow?
|
|
mov GR_min_exp = 0x0ff81 // Exponent of minimum float
|
|
(p9) br.cond.spnt SCALBNF_UNORM // Branch if x=unorm
|
|
}
|
|
;;
|
|
|
|
SCALBNF_COMMON:
|
|
// Main path continues. Also return here from x=unorm path.
|
|
// Create 2**N
|
|
.pred.rel "mutex",p7,p8
|
|
{ .mfi
|
|
setf.exp FR_Two_N = GR_N_Biased
|
|
nop.f 0
|
|
(p7) mov GR_N_as_int = GR_Big // Limit max N
|
|
}
|
|
{ .mfi
|
|
(p8) mov GR_N_as_int = GR_NBig // Limit min N
|
|
nop.f 0
|
|
(p8) cmp.eq p7,p0 = r0,r0 // Set p7 if |N| big
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Create biased exponent for 2**N for N big
|
|
// Is N zero?
|
|
//
|
|
{ .mfi
|
|
(p7) add GR_N_Biased = GR_Bias,GR_N_as_int
|
|
nop.f 0
|
|
cmp.eq.or p6,p0 = r33,r0
|
|
}
|
|
{ .mfi
|
|
mov GR_pos_ov_limit = 0x1007f // Exponent for positive overflow
|
|
nop.f 0
|
|
mov GR_exp_mask = 0x1ffff // Exponent mask
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Create 2**N for N big
|
|
// Return x when N = 0 or X = Nan, Inf, Zero
|
|
//
|
|
{ .mfi
|
|
(p7) setf.exp FR_Two_N = GR_N_Biased
|
|
nop.f 0
|
|
mov GR_min_den_exp = 0x0ff81 - 23 // Exponent of min denorm float
|
|
}
|
|
{ .mfb
|
|
and GR_exp_X = GR_exp_mask, GR_signexp_X
|
|
(p6) fma.s.s0 FR_Result = FR_Floating_X, f1, f0
|
|
(p6) br.ret.spnt b0
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Raise Denormal operand flag with compare
|
|
// Compute biased result exponent
|
|
//
|
|
{ .mfi
|
|
add GR_exp_Result = GR_exp_X, GR_N_as_int
|
|
fcmp.ge.s0 p0,p11 = FR_Floating_X,f0
|
|
mov GR_neg_ov_limit = 0x3007f // Exponent for negative overflow
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Do final operation
|
|
//
|
|
{ .mfi
|
|
cmp.lt p7,p6 = GR_exp_Result, GR_max_exp // Test no overflow
|
|
fma.s.s0 FR_Result = FR_Two_N,FR_Norm_X,f0
|
|
cmp.lt p9,p0 = GR_exp_Result, GR_min_den_exp // Test sure underflow
|
|
}
|
|
{ .mfb
|
|
nop.m 0
|
|
nop.f 0
|
|
(p9) br.cond.spnt SCALBNF_UNDERFLOW // Branch if certain underflow
|
|
}
|
|
;;
|
|
|
|
{ .mib
|
|
(p6) cmp.gt.unc p6,p8 = GR_exp_Result, GR_max_exp // Test sure overflow
|
|
(p7) cmp.ge.unc p7,p9 = GR_exp_Result, GR_min_exp // Test no over/underflow
|
|
(p7) br.ret.sptk b0 // Return from main path
|
|
}
|
|
;;
|
|
|
|
{ .bbb
|
|
(p6) br.cond.spnt SCALBNF_OVERFLOW // Branch if certain overflow
|
|
(p8) br.cond.spnt SCALBNF_POSSIBLE_OVERFLOW // Branch if possible overflow
|
|
(p9) br.cond.spnt SCALBNF_POSSIBLE_UNDERFLOW // Branch if possible underflow
|
|
}
|
|
;;
|
|
|
|
// Here if possible underflow.
|
|
// Resulting exponent: 0x0ff81-23 <= exp_Result < 0x0ff81
|
|
SCALBNF_POSSIBLE_UNDERFLOW:
|
|
//
|
|
// Here if possible overflow.
|
|
// Resulting exponent: 0x1007e = exp_Result
|
|
SCALBNF_POSSIBLE_OVERFLOW:
|
|
|
|
// Set up necessary status fields
|
|
//
|
|
// S0 user supplied status
|
|
// S2 user supplied status + WRE + TD (Overflows)
|
|
// S3 user supplied status + FZ + TD (Underflows)
|
|
//
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s3 0x7F,0x41
|
|
nop.i 0
|
|
}
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s2 0x7F,0x42
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Do final operation with s2 and s3
|
|
//
|
|
{ .mfi
|
|
setf.exp FR_NBig = GR_neg_ov_limit
|
|
fma.s.s3 FR_Result3 = FR_Two_N,FR_Norm_X,f0
|
|
nop.i 0
|
|
}
|
|
{ .mfi
|
|
setf.exp FR_Big = GR_pos_ov_limit
|
|
fma.s.s2 FR_Result2 = FR_Two_N,FR_Norm_X,f0
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
// Check for overflow or underflow.
|
|
// Restore s3
|
|
// Restore s2
|
|
//
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s3 0x7F,0x40
|
|
nop.i 0
|
|
}
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s2 0x7F,0x40
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Is the result zero?
|
|
//
|
|
{ .mfi
|
|
nop.m 0
|
|
fclass.m p6, p0 = FR_Result3, 0x007
|
|
nop.i 0
|
|
}
|
|
{ .mfi
|
|
nop.m 0
|
|
fcmp.ge.s1 p7, p8 = FR_Result2 , FR_Big
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Detect masked underflow - Tiny + Inexact Only
|
|
//
|
|
{ .mfi
|
|
nop.m 0
|
|
(p6) fcmp.neq.unc.s1 p6, p0 = FR_Result , FR_Result2
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Is result bigger the allowed range?
|
|
// Branch out for underflow
|
|
//
|
|
{ .mfb
|
|
nop.m 0
|
|
(p8) fcmp.le.unc.s1 p9, p10 = FR_Result2 , FR_NBig
|
|
(p6) br.cond.spnt SCALBNF_UNDERFLOW
|
|
}
|
|
;;
|
|
|
|
//
|
|
// Branch out for overflow
|
|
//
|
|
{ .bbb
|
|
(p7) br.cond.spnt SCALBNF_OVERFLOW
|
|
(p9) br.cond.spnt SCALBNF_OVERFLOW
|
|
br.ret.sptk b0 // Return from main path.
|
|
}
|
|
;;
|
|
|
|
// Here if result overflows
|
|
SCALBNF_OVERFLOW:
|
|
{ .mib
|
|
alloc r32=ar.pfs,3,0,4,0
|
|
addl GR_Tag = 205, r0 // Set error tag for overflow
|
|
br.cond.sptk __libm_error_region // Call error support for overflow
|
|
}
|
|
;;
|
|
|
|
// Here if result underflows
|
|
SCALBNF_UNDERFLOW:
|
|
{ .mib
|
|
alloc r32=ar.pfs,3,0,4,0
|
|
addl GR_Tag = 206, r0 // Set error tag for underflow
|
|
br.cond.sptk __libm_error_region // Call error support for underflow
|
|
}
|
|
;;
|
|
|
|
// Here if x=unorm
|
|
SCALBNF_UNORM:
|
|
{ .mib
|
|
getf.exp GR_signexp_X = FR_Norm_X // Get signexp of normalized x
|
|
nop.i 0
|
|
br.cond.sptk SCALBNF_COMMON // Return to main path
|
|
}
|
|
;;
|
|
|
|
|
|
GLOBAL_LIBM_END(__libm_scalblnf)
|
|
LOCAL_LIBM_ENTRY(__libm_error_region)
|
|
|
|
//
|
|
// Get stack address of N
|
|
//
|
|
.prologue
|
|
{ .mfi
|
|
add GR_Parameter_Y=-32,sp
|
|
nop.f 0
|
|
.save ar.pfs,GR_SAVE_PFS
|
|
mov GR_SAVE_PFS=ar.pfs
|
|
}
|
|
//
|
|
// Adjust sp
|
|
//
|
|
{ .mfi
|
|
.fframe 64
|
|
add sp=-64,sp
|
|
nop.f 0
|
|
mov GR_SAVE_GP=gp
|
|
};;
|
|
|
|
//
|
|
// Store N on stack in correct position
|
|
// Locate the address of x on stack
|
|
//
|
|
{ .mmi
|
|
st8 [GR_Parameter_Y] = GR_N_as_int,16
|
|
add GR_Parameter_X = 16,sp
|
|
.save b0, GR_SAVE_B0
|
|
mov GR_SAVE_B0=b0
|
|
};;
|
|
|
|
//
|
|
// Store x on the stack.
|
|
// Get address for result on stack.
|
|
//
|
|
.body
|
|
{ .mib
|
|
stfs [GR_Parameter_X] = FR_Norm_X
|
|
add GR_Parameter_RESULT = 0,GR_Parameter_Y
|
|
nop.b 0
|
|
}
|
|
{ .mib
|
|
stfs [GR_Parameter_Y] = FR_Result
|
|
add GR_Parameter_Y = -16,GR_Parameter_Y
|
|
br.call.sptk b0=__libm_error_support#
|
|
};;
|
|
|
|
//
|
|
// Get location of result on stack
|
|
//
|
|
{ .mmi
|
|
add GR_Parameter_RESULT = 48,sp
|
|
nop.m 0
|
|
nop.i 0
|
|
};;
|
|
|
|
//
|
|
// Get the new result
|
|
//
|
|
{ .mmi
|
|
ldfs FR_Result = [GR_Parameter_RESULT]
|
|
.restore sp
|
|
add sp = 64,sp
|
|
mov b0 = GR_SAVE_B0
|
|
};;
|
|
|
|
//
|
|
// Restore gp, ar.pfs and return
|
|
//
|
|
{ .mib
|
|
mov gp = GR_SAVE_GP
|
|
mov ar.pfs = GR_SAVE_PFS
|
|
br.ret.sptk b0
|
|
};;
|
|
|
|
LOCAL_LIBM_END(__libm_error_region)
|
|
|
|
.type __libm_error_support#,@function
|
|
.global __libm_error_support#
|