You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
298 lines
7.7 KiB
298 lines
7.7 KiB
.file "logbf.s"
|
|
|
|
// Copyright (c) 2000, 2001, Intel Corporation
|
|
// All rights reserved.
|
|
//
|
|
// 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.
|
|
//
|
|
// WARRANTY DISCLAIMER
|
|
//
|
|
// 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://developer.intel.com/opensource.
|
|
//
|
|
// History
|
|
//==============================================================
|
|
// 2/02/00 Initial version
|
|
// 2/16/00 Modified to conform to C9X
|
|
// 3/16/00 Improved speed
|
|
// 4/04/00 Unwind support added
|
|
// 5/30/00 Fixed bug when x double-extended denormal
|
|
// 8/15/00 Bundle added after call to __libm_error_support to properly
|
|
// set [the previously overwritten] GR_Parameter_RESULT.
|
|
//
|
|
// API
|
|
//==============================================================
|
|
// float _logbf( float x);
|
|
//
|
|
// Overview of operation
|
|
//==============================================================
|
|
// The logbf function extracts the exponent of x as an integer in
|
|
// floating-point format.
|
|
// logbf computes log2 of x as a float
|
|
|
|
// logbf is similar to ilogbf but differs in the following ways:
|
|
// +-inf
|
|
// ilogbf: returns INT_MAX
|
|
// logbf: returns +inf
|
|
// Nan returns FP_LOGBNAN (which is either INT_MAX or INT_MIN)
|
|
// ilogbf: returns INT_MAX (7fffffff)
|
|
// logbf: returns QNAN (quietized SNAN)
|
|
// 0 returns FP_ILOGB0 (which is either INT_MIN or -INT_MAX)
|
|
// ilogbf: returns -INT_MAX (80000001)
|
|
// logbf: returns -inf, raises the divide-by-zero exception,
|
|
// and calls libm_error_support to set domain error
|
|
//
|
|
// Registers used
|
|
//==============================================================
|
|
// general registers used:
|
|
// ar.pfs r32
|
|
// r33 -> r37
|
|
// r38 -> r41 used as parameters to error path
|
|
//
|
|
// predicate registers used:
|
|
// p6, p7, p8
|
|
//
|
|
// floating-point registers used:
|
|
// f9, f10, f11
|
|
// f8, input
|
|
|
|
GR_SAVE_B0 = r34
|
|
// r40 is address of table of coefficients
|
|
GR_SAVE_PFS = r32
|
|
GR_SAVE_GP = r35
|
|
|
|
GR_Parameter_X = r38
|
|
GR_Parameter_Y = r39
|
|
GR_Parameter_RESULT = r40
|
|
GR_Parameter_TAG = r41
|
|
|
|
FR_X = f8
|
|
FR_Y = f0
|
|
FR_RESULT = f10
|
|
|
|
|
|
.align 32
|
|
.global _logbf#
|
|
|
|
.section .text
|
|
.proc _logbf#
|
|
.align 32
|
|
|
|
|
|
_logbf:
|
|
|
|
// qnan snan inf norm unorm 0 -+
|
|
// 0 0 0 0 1 0 11
|
|
// 0 b
|
|
{ .mfi
|
|
alloc r32=ar.pfs,1,5,4,0
|
|
fclass.m.unc p8,p0 = f8, 0x0b
|
|
nop.i 999
|
|
}
|
|
// X NORMAL
|
|
// r37 = exp(f8) - - 0xffff
|
|
// sig(f8) = r37
|
|
// f8 = convert_to_fp (sig))
|
|
{ .mfi
|
|
getf.exp r35 = f8
|
|
fnorm f10=f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// qnan snan inf norm unorm 0 -+
|
|
// 1 1 1 0 0 0 11
|
|
// e 3
|
|
{ .mmf
|
|
mov r33 = 0xffff
|
|
mov r34 = 0x1ffff
|
|
fclass.m.unc p6,p0 = f8, 0xe3 ;;
|
|
}
|
|
|
|
{ .mfb
|
|
and r36 = r35, r34
|
|
fclass.m.unc p7,p0 = f8, 0x07
|
|
(p8) br.cond.spnt LOGB_DENORM ;;
|
|
}
|
|
|
|
{ .mib
|
|
sub r37 = r36, r33
|
|
nop.i 999
|
|
(p6) br.cond.spnt LOGB_NAN_INF ;;
|
|
}
|
|
|
|
{ .mib
|
|
setf.sig f9 = r37
|
|
nop.i 999
|
|
(p7) br.cond.spnt LOGB_ZERO ;;
|
|
}
|
|
|
|
{ .mfi
|
|
nop.m 999
|
|
fcvt.xf f10 = f9
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfb
|
|
nop.m 999
|
|
fnorm.s f8 = f10
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
LOGB_DENORM:
|
|
// Form signexp of 2^64 in case need to scale denormal
|
|
// Check to see if double-extended denormal
|
|
{ .mfi
|
|
mov r38 = 0x1003f
|
|
fclass.m.unc p8,p0 = f10, 0x0b
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Form 2^64 in case need to scale denormal
|
|
{ .mfi
|
|
setf.exp f11 = r38
|
|
nop.f 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// If double-extended denormal add 64 to exponent bias for scaling
|
|
// If double-extended denormal form x * 2^64 which is normal
|
|
{ .mfi
|
|
(p8) add r33 = 64, r33
|
|
(p8) fmpy f10 = f10, f11
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
// Logic is the same as normal path but use normalized input
|
|
{ .mmi
|
|
getf.exp r35 = f10 ;;
|
|
nop.m 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mmi
|
|
and r36 = r35, r34 ;;
|
|
sub r37 = r36, r33
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mmi
|
|
setf.sig f9 = r37
|
|
nop.m 999
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfi
|
|
nop.m 999
|
|
fcvt.xf f10 = f9
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfb
|
|
nop.m 999
|
|
fnorm.s f8 = f10
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
LOGB_NAN_INF:
|
|
|
|
// X NAN or INFINITY, return f8 * f8
|
|
{ .mfb
|
|
nop.m 999
|
|
fma.s f8= f8,f8,f0
|
|
br.ret.sptk b0 ;;
|
|
}
|
|
|
|
LOGB_ZERO:
|
|
|
|
// X ZERO
|
|
// return -1.0/fabs(f8)=-inf, set divide-by-zero flag, call error support
|
|
{ .mfi
|
|
nop.m 999
|
|
fmerge.s f9 = f0,f8
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfi
|
|
nop.m 999
|
|
fmerge.ns f10 = f0,f9
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
{ .mfi
|
|
nop.m 999
|
|
frcpa f10,p6 = f1,f10
|
|
nop.i 999 ;;
|
|
}
|
|
|
|
.endp _logbf
|
|
|
|
|
|
.proc __libm_error_region
|
|
__libm_error_region:
|
|
.prologue
|
|
{ .mii
|
|
add GR_Parameter_Y=-32,sp // Parameter 2 value
|
|
mov GR_Parameter_TAG = 152
|
|
.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
|
|
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
|
|
};;
|
|
.body
|
|
{ .mib
|
|
stfs [GR_Parameter_X] = FR_X // Store Parameter 1 on stack
|
|
add GR_Parameter_RESULT = 0,GR_Parameter_Y
|
|
nop.b 0 // 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
|
|
};;
|
|
{ .mmi
|
|
nop.m 0
|
|
nop.m 0
|
|
add GR_Parameter_RESULT = 48,sp
|
|
};;
|
|
{ .mmi
|
|
ldfs f8 = [GR_Parameter_RESULT] // Get return result off stack
|
|
.restore
|
|
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
|
|
};;
|
|
|
|
.endp __libm_error_region
|
|
|
|
|
|
|
|
.type __libm_error_support#,@function
|
|
.global __libm_error_support#
|