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diff --git a/arch/parisc/math-emu/sfmpy.c b/arch/parisc/math-emu/sfmpy.c
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+/*
+ * Linux/PA-RISC Project (http://www.parisc-linux.org/)
+ *
+ * Floating-point emulation code
+ * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+/*
+ * BEGIN_DESC
+ *
+ * File:
+ * @(#) pa/spmath/sfmpy.c $Revision: 1.1 $
+ *
+ * Purpose:
+ * Single Precision Floating-point Multiply
+ *
+ * External Interfaces:
+ * sgl_fmpy(srcptr1,srcptr2,dstptr,status)
+ *
+ * Internal Interfaces:
+ *
+ * Theory:
+ * <<please update with a overview of the operation of this file>>
+ *
+ * END_DESC
+*/
+
+
+#include "float.h"
+#include "sgl_float.h"
+
+/*
+ * Single Precision Floating-point Multiply
+ */
+
+int
+sgl_fmpy(
+ sgl_floating_point *srcptr1,
+ sgl_floating_point *srcptr2,
+ sgl_floating_point *dstptr,
+ unsigned int *status)
+{
+ register unsigned int opnd1, opnd2, opnd3, result;
+ register int dest_exponent, count;
+ register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
+ boolean is_tiny;
+
+ opnd1 = *srcptr1;
+ opnd2 = *srcptr2;
+ /*
+ * set sign bit of result
+ */
+ if (Sgl_sign(opnd1) ^ Sgl_sign(opnd2)) Sgl_setnegativezero(result);
+ else Sgl_setzero(result);
+ /*
+ * check first operand for NaN's or infinity
+ */
+ if (Sgl_isinfinity_exponent(opnd1)) {
+ if (Sgl_iszero_mantissa(opnd1)) {
+ if (Sgl_isnotnan(opnd2)) {
+ if (Sgl_iszero_exponentmantissa(opnd2)) {
+ /*
+ * invalid since operands are infinity
+ * and zero
+ */
+ if (Is_invalidtrap_enabled())
+ return(INVALIDEXCEPTION);
+ Set_invalidflag();
+ Sgl_makequietnan(result);
+ *dstptr = result;
+ return(NOEXCEPTION);
+ }
+ /*
+ * return infinity
+ */
+ Sgl_setinfinity_exponentmantissa(result);
+ *dstptr = result;
+ return(NOEXCEPTION);
+ }
+ }
+ else {
+ /*
+ * is NaN; signaling or quiet?
+ */
+ if (Sgl_isone_signaling(opnd1)) {
+ /* trap if INVALIDTRAP enabled */
+ if (Is_invalidtrap_enabled())
+ return(INVALIDEXCEPTION);
+ /* make NaN quiet */
+ Set_invalidflag();
+ Sgl_set_quiet(opnd1);
+ }
+ /*
+ * is second operand a signaling NaN?
+ */
+ else if (Sgl_is_signalingnan(opnd2)) {
+ /* trap if INVALIDTRAP enabled */
+ if (Is_invalidtrap_enabled())
+ return(INVALIDEXCEPTION);
+ /* make NaN quiet */
+ Set_invalidflag();
+ Sgl_set_quiet(opnd2);
+ *dstptr = opnd2;
+ return(NOEXCEPTION);
+ }
+ /*
+ * return quiet NaN
+ */
+ *dstptr = opnd1;
+ return(NOEXCEPTION);
+ }
+ }
+ /*
+ * check second operand for NaN's or infinity
+ */
+ if (Sgl_isinfinity_exponent(opnd2)) {
+ if (Sgl_iszero_mantissa(opnd2)) {
+ if (Sgl_iszero_exponentmantissa(opnd1)) {
+ /* invalid since operands are zero & infinity */
+ if (Is_invalidtrap_enabled())
+ return(INVALIDEXCEPTION);
+ Set_invalidflag();
+ Sgl_makequietnan(opnd2);
+ *dstptr = opnd2;
+ return(NOEXCEPTION);
+ }
+ /*
+ * return infinity
+ */
+ Sgl_setinfinity_exponentmantissa(result);
+ *dstptr = result;
+ return(NOEXCEPTION);
+ }
+ /*
+ * is NaN; signaling or quiet?
+ */
+ if (Sgl_isone_signaling(opnd2)) {
+ /* trap if INVALIDTRAP enabled */
+ if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+
+ /* make NaN quiet */
+ Set_invalidflag();
+ Sgl_set_quiet(opnd2);
+ }
+ /*
+ * return quiet NaN
+ */
+ *dstptr = opnd2;
+ return(NOEXCEPTION);
+ }
+ /*
+ * Generate exponent
+ */
+ dest_exponent = Sgl_exponent(opnd1) + Sgl_exponent(opnd2) - SGL_BIAS;
+
+ /*
+ * Generate mantissa
+ */
+ if (Sgl_isnotzero_exponent(opnd1)) {
+ /* set hidden bit */
+ Sgl_clear_signexponent_set_hidden(opnd1);
+ }
+ else {
+ /* check for zero */
+ if (Sgl_iszero_mantissa(opnd1)) {
+ Sgl_setzero_exponentmantissa(result);
+ *dstptr = result;
+ return(NOEXCEPTION);
+ }
+ /* is denormalized, adjust exponent */
+ Sgl_clear_signexponent(opnd1);
+ Sgl_leftshiftby1(opnd1);
+ Sgl_normalize(opnd1,dest_exponent);
+ }
+ /* opnd2 needs to have hidden bit set with msb in hidden bit */
+ if (Sgl_isnotzero_exponent(opnd2)) {
+ Sgl_clear_signexponent_set_hidden(opnd2);
+ }
+ else {
+ /* check for zero */
+ if (Sgl_iszero_mantissa(opnd2)) {
+ Sgl_setzero_exponentmantissa(result);
+ *dstptr = result;
+ return(NOEXCEPTION);
+ }
+ /* is denormalized; want to normalize */
+ Sgl_clear_signexponent(opnd2);
+ Sgl_leftshiftby1(opnd2);
+ Sgl_normalize(opnd2,dest_exponent);
+ }
+
+ /* Multiply two source mantissas together */
+
+ Sgl_leftshiftby4(opnd2); /* make room for guard bits */
+ Sgl_setzero(opnd3);
+ /*
+ * Four bits at a time are inspected in each loop, and a
+ * simple shift and add multiply algorithm is used.
+ */
+ for (count=1;count<SGL_P;count+=4) {
+ stickybit |= Slow4(opnd3);
+ Sgl_rightshiftby4(opnd3);
+ if (Sbit28(opnd1)) Sall(opnd3) += (Sall(opnd2) << 3);
+ if (Sbit29(opnd1)) Sall(opnd3) += (Sall(opnd2) << 2);
+ if (Sbit30(opnd1)) Sall(opnd3) += (Sall(opnd2) << 1);
+ if (Sbit31(opnd1)) Sall(opnd3) += Sall(opnd2);
+ Sgl_rightshiftby4(opnd1);
+ }
+ /* make sure result is left-justified */
+ if (Sgl_iszero_sign(opnd3)) {
+ Sgl_leftshiftby1(opnd3);
+ }
+ else {
+ /* result mantissa >= 2. */
+ dest_exponent++;
+ }
+ /* check for denormalized result */
+ while (Sgl_iszero_sign(opnd3)) {
+ Sgl_leftshiftby1(opnd3);
+ dest_exponent--;
+ }
+ /*
+ * check for guard, sticky and inexact bits
+ */
+ stickybit |= Sgl_all(opnd3) << (SGL_BITLENGTH - SGL_EXP_LENGTH + 1);
+ guardbit = Sbit24(opnd3);
+ inexact = guardbit | stickybit;
+
+ /* re-align mantissa */
+ Sgl_rightshiftby8(opnd3);
+
+ /*
+ * round result
+ */
+ if (inexact && (dest_exponent>0 || Is_underflowtrap_enabled())) {
+ Sgl_clear_signexponent(opnd3);
+ switch (Rounding_mode()) {
+ case ROUNDPLUS:
+ if (Sgl_iszero_sign(result))
+ Sgl_increment(opnd3);
+ break;
+ case ROUNDMINUS:
+ if (Sgl_isone_sign(result))
+ Sgl_increment(opnd3);
+ break;
+ case ROUNDNEAREST:
+ if (guardbit) {
+ if (stickybit || Sgl_isone_lowmantissa(opnd3))
+ Sgl_increment(opnd3);
+ }
+ }
+ if (Sgl_isone_hidden(opnd3)) dest_exponent++;
+ }
+ Sgl_set_mantissa(result,opnd3);
+
+ /*
+ * Test for overflow
+ */
+ if (dest_exponent >= SGL_INFINITY_EXPONENT) {
+ /* trap if OVERFLOWTRAP enabled */
+ if (Is_overflowtrap_enabled()) {
+ /*
+ * Adjust bias of result
+ */
+ Sgl_setwrapped_exponent(result,dest_exponent,ovfl);
+ *dstptr = result;
+ if (inexact)
+ if (Is_inexacttrap_enabled())
+ return(OVERFLOWEXCEPTION | INEXACTEXCEPTION);
+ else Set_inexactflag();
+ return(OVERFLOWEXCEPTION);
+ }
+ inexact = TRUE;
+ Set_overflowflag();
+ /* set result to infinity or largest number */
+ Sgl_setoverflow(result);
+ }
+ /*
+ * Test for underflow
+ */
+ else if (dest_exponent <= 0) {
+ /* trap if UNDERFLOWTRAP enabled */
+ if (Is_underflowtrap_enabled()) {
+ /*
+ * Adjust bias of result
+ */
+ Sgl_setwrapped_exponent(result,dest_exponent,unfl);
+ *dstptr = result;
+ if (inexact)
+ if (Is_inexacttrap_enabled())
+ return(UNDERFLOWEXCEPTION | INEXACTEXCEPTION);
+ else Set_inexactflag();
+ return(UNDERFLOWEXCEPTION);
+ }
+
+ /* Determine if should set underflow flag */
+ is_tiny = TRUE;
+ if (dest_exponent == 0 && inexact) {
+ switch (Rounding_mode()) {
+ case ROUNDPLUS:
+ if (Sgl_iszero_sign(result)) {
+ Sgl_increment(opnd3);
+ if (Sgl_isone_hiddenoverflow(opnd3))
+ is_tiny = FALSE;
+ Sgl_decrement(opnd3);
+ }
+ break;
+ case ROUNDMINUS:
+ if (Sgl_isone_sign(result)) {
+ Sgl_increment(opnd3);
+ if (Sgl_isone_hiddenoverflow(opnd3))
+ is_tiny = FALSE;
+ Sgl_decrement(opnd3);
+ }
+ break;
+ case ROUNDNEAREST:
+ if (guardbit && (stickybit ||
+ Sgl_isone_lowmantissa(opnd3))) {
+ Sgl_increment(opnd3);
+ if (Sgl_isone_hiddenoverflow(opnd3))
+ is_tiny = FALSE;
+ Sgl_decrement(opnd3);
+ }
+ break;
+ }
+ }
+
+ /*
+ * denormalize result or set to signed zero
+ */
+ stickybit = inexact;
+ Sgl_denormalize(opnd3,dest_exponent,guardbit,stickybit,inexact);
+
+ /* return zero or smallest number */
+ if (inexact) {
+ switch (Rounding_mode()) {
+ case ROUNDPLUS:
+ if (Sgl_iszero_sign(result)) {
+ Sgl_increment(opnd3);
+ }
+ break;
+ case ROUNDMINUS:
+ if (Sgl_isone_sign(result)) {
+ Sgl_increment(opnd3);
+ }
+ break;
+ case ROUNDNEAREST:
+ if (guardbit && (stickybit ||
+ Sgl_isone_lowmantissa(opnd3))) {
+ Sgl_increment(opnd3);
+ }
+ break;
+ }
+ if (is_tiny) Set_underflowflag();
+ }
+ Sgl_set_exponentmantissa(result,opnd3);
+ }
+ else Sgl_set_exponent(result,dest_exponent);
+ *dstptr = result;
+
+ /* check for inexact */
+ if (inexact) {
+ if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
+ else Set_inexactflag();
+ }
+ return(NOEXCEPTION);
+}
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