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+.file "round.s"
+
+// Copyright (c) 2000, 2001, Intel Corporation
+// All rights reserved.
+// 
+// Contributed 10/25/2000 by John Harrison, Cristina Iordache, Ted Kubaska,
+// Bob Norin, Tom Rowan, 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
+//==============================================================
+// 10/25/2000: Created
+//==============================================================
+//
+// API
+//==============================================================
+// double round(double x)
+//
+
+#include "libm_support.h"
+
+// general input registers:  
+//
+round_GR_half      = r14
+round_GR_big       = r15
+round_GR_expmask   = r16
+round_GR_signexp   = r17
+round_GR_exp       = r18
+round_GR_expdiff   = r19
+
+// predicate registers used: 
+// p6 - p10
+
+// floating-point registers used: 
+
+ROUND_NORM_f8        = f9                        
+ROUND_TRUNC_f8       = f10
+ROUND_RINT_f8        = f11
+ROUND_FLOAT_TRUNC_f8 = f12
+ROUND_FLOAT_RINT_f8  = f13
+ROUND_REMAINDER      = f14
+ROUND_HALF           = f15
+
+// Overview of operation
+//==============================================================
+
+// double round(double x)
+// Return an integer value (represented as a double) that is x 
+// rounded to nearest integer, halfway cases rounded away from 
+// zero. 
+//  if x>0   result = trunc(x+0.5)
+//  if x<0   result = trunc(x-0.5)
+// *******************************************************************************
+
+// Set denormal flag for denormal input and
+// and take denormal fault if necessary.
+
+// If x is NAN, ZERO, INFINITY, or >= 2^52 then return
+
+// qnan snan inf norm     unorm 0 -+
+// 1    1    1   0        0     1 11     0xe7
+
+
+.align 32
+.global round#
+
+.section .text
+.proc  round#
+.align 32
+
+
+round: 
+	
+// Get exponent for +0.5
+// Truncate x to integer
+{ .mfi
+      addl           round_GR_half  = 0x0fffe, r0
+      fcvt.fx.trunc.s1     ROUND_TRUNC_f8 = f8
+      nop.i 999
+}
+	
+// Get signexp of x
+// Normalize input
+// Form exponent mask
+{ .mfi
+      getf.exp  round_GR_signexp = f8
+      fnorm     ROUND_NORM_f8 = f8                        
+      addl      round_GR_expmask  = 0x1ffff, r0 ;;
+}
+
+// Form +0.5
+// Round x to integer
+{ .mfi
+      setf.exp    ROUND_HALF  = round_GR_half                      
+      fcvt.fx.s1  ROUND_RINT_f8 = f8
+      nop.i 999 ;;
+}
+// Get exp of x
+// Test for NAN, INF, ZERO
+// Get exponent at which input has no fractional part
+{ .mfi
+      and         round_GR_exp = round_GR_expmask, round_GR_signexp
+      fclass.m    p8,p9 = f8,0xe7
+      addl        round_GR_big  = 0x10033, r0 ;;
+}
+
+// Get exp-bigexp
+// If exp is so big there is no fractional part, then turn on p8, off p9
+{ .mmi
+      sub    round_GR_expdiff = round_GR_exp, round_GR_big ;;
+#ifdef _LIBC
+(p9)  cmp.lt.or.andcm  p8,p9 = r0, round_GR_expdiff
+#else
+(p9)  cmp.ge.or.andcm  p8,p9 = round_GR_expdiff, r0
+#endif
+      nop.i 999 ;;
+}
+     
+// Set p6 if x<0, else set p7
+{ .mfi
+      nop.m 999
+(p9)  fcmp.lt.unc  p6,p7 = f8,f0
+      nop.i 999
+}
+	
+// If NAN, INF, ZERO, or no fractional part, result is just normalized input
+{ .mfi
+      nop.m 999
+(p8)  fnorm.d.s0  f8 = f8
+      nop.i 999 ;;
+}
+
+// Float the truncated integer
+{ .mfi
+      nop.m 999
+(p9)  fcvt.xf     ROUND_FLOAT_TRUNC_f8 = ROUND_TRUNC_f8
+      nop.i 999 ;;
+}
+
+// Float the rounded integer to get preliminary result
+{ .mfi
+      nop.m 999
+(p9)  fcvt.xf     ROUND_FLOAT_RINT_f8 = ROUND_RINT_f8
+      nop.i 999 ;;
+}
+
+// If x<0 and the difference of the truncated input minus the input is 0.5
+//    then result = truncated input - 1.0
+// Else if x>0 and the difference of the input minus truncated input is 0.5
+//    then result = truncated input + 1.0
+// Else 
+//    result = rounded input
+// Endif
+{ .mfi
+      nop.m 999
+(p6)  fsub.s1   ROUND_REMAINDER = ROUND_FLOAT_TRUNC_f8, ROUND_NORM_f8 
+      nop.i 999
+}
+	
+{ .mfi
+      nop.m 999
+(p7)  fsub.s1   ROUND_REMAINDER = ROUND_NORM_f8, ROUND_FLOAT_TRUNC_f8
+      nop.i 999 ;;
+}
+
+// Assume preliminary result is rounded integer
+{ .mfi
+      nop.m 999
+(p9)  fnorm.d.s0  f8 = ROUND_FLOAT_RINT_f8
+      nop.i 999 
+}
+
+// If x<0, test if result=0
+{ .mfi
+      nop.m 999
+(p6)  fcmp.eq.unc  p10,p0 = ROUND_FLOAT_RINT_f8,f0
+      nop.i 999 ;;
+}
+
+// If x<0 and result=0, set result=-0
+{ .mfi
+      nop.m 999
+(p10) fmerge.ns  f8 = f1,f8
+      nop.i 999
+}
+	
+// If x<0, test if remainder=0.5
+{ .mfi
+      nop.m 999
+(p6)  fcmp.eq.unc  p6,p0 = ROUND_REMAINDER, ROUND_HALF
+      nop.i 999 ;; 
+}
+	
+// If x>0, test if remainder=0.5
+{ .mfi
+      nop.m 999
+(p7)  fcmp.eq.unc  p7,p0 = ROUND_REMAINDER, ROUND_HALF
+      nop.i 999 ;;
+}
+
+// If x<0 and remainder=0.5, result=truncated-1.0
+// If x>0 and remainder=0.5, result=truncated+1.0
+// Exit
+.pred.rel "mutex",p6,p7
+{ .mfi
+      nop.m 999
+(p6)  fsub.d.s0  f8 = ROUND_FLOAT_TRUNC_f8,f1
+      nop.i 999 
+}
+	
+{ .mfb
+      nop.m 999
+(p7)  fadd.d.s0  f8 = ROUND_FLOAT_TRUNC_f8,f1
+      br.ret.sptk  b0 ;;
+}
+
+.endp round
+ASM_SIZE_DIRECTIVE(round)