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+.file "significand.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
+// 4/04/00 Unwind support added
+// 5/31/00: Fixed bug when x a double-extended denormal
+//
+// API
+//==============================================================
+// double significand(double x)
+//
+// Overview of operation
+//==============================================================
+// If x = sig * 2**n with 1 <= sig < 2
+// significand returns sig
+//
+// predicate registers used:
+// p6, p7
+//
+// floating-point registers used:
+// f8, f9, f10
+
+#include "libm_support.h"
+
+.align 32
+.global significand#
+
+.section .text
+.proc significand#
+.align 32
+
+significand:
+
+// qnan snan inf norm unorm 0 -+
+// 1 1 1 0 0 1 11
+
+// f10 gets f8(sign) with f1(exp,significand)
+{ .mfi
+ nop.m 999
+(p0) fmerge.s f10 = f8,f1
+ nop.i 999
+}
+{ .mfi
+ nop.m 999
+(p0) fnorm f9 = f8
+ nop.i 999 ;;
+}
+
+// Test for denormal input
+{ .mfi
+ nop.m 999
+(p0) fclass.m.unc p7,p0 = f8, 0x0b
+ nop.i 999 ;;
+}
+
+// p6 = TRUE ==> x is not (nan,inf,0)
+// return sign(f8) exp(f1) significand(f8)
+// else x is (nan,inf,0)
+// return sign(f8) exp(f8) significand(f8), normalized.
+{ .mfi
+ nop.m 999
+(p0) fclass.m.unc p0,p6 = f8, 0xe7
+ nop.i 999 ;;
+}
+
+{ .mmb
+ nop.m 999
+ nop.m 999
+(p7) br.cond.spnt L(SIGNIFICAND_DENORM) ;; // Branch if x denormal
+}
+
+{ .mfi
+ nop.m 999
+(p6) fmerge.se f8 = f10,f8
+ nop.i 999 ;;
+}
+
+{ .mfb
+ nop.m 999
+(p0) fnorm.d f8 = f8
+(p0) br.ret.sptk b0 ;;
+}
+
+L(SIGNIFICAND_DENORM):
+// Here if x denorm
+{ .mfi
+ nop.m 999
+(p0) fmerge.se f8 = f10,f9
+ nop.i 999 ;;
+}
+
+// Check if fnorm(x) still denormal, means x double-extended denormal
+{ .mfi
+ nop.m 999
+(p0) fclass.m.unc p7,p0 = f9, 0x0b
+ nop.i 999 ;;
+}
+
+// This will be the final result unless x double-extended denormal
+{ .mfi
+ nop.m 999
+(p0) fnorm.d f8 = f8
+ nop.i 999 ;;
+}
+
+// If x double-extended denorm, then significand ok, but must merge in
+// correct signexp
+{ .mfi
+ nop.m 999
+(p7) fmerge.se f8 = f10,f8
+ nop.i 999 ;;
+}
+
+// Final normalization if x double-extended denorm
+{ .mfb
+ nop.m 999
+(p7) fnorm.d f8 = f8
+(p0) br.ret.sptk b0 ;;
+}
+
+.endp significand
+ASM_SIZE_DIRECTIVE(significand)