1 files changed, 518 insertions, 0 deletions

diff --git a/arch/parisc/math-emu/sfadd.c b/arch/parisc/math-emu/sfadd.c
new file mode 100644
index 000000000000..008d721b5d22
--- /dev/null
+++ b/arch/parisc/math-emu/sfadd.c
@@ -0,0 +1,518 @@
+/*
+ * 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/sfadd.c               $Revision: 1.1 $
+ *
+ *  Purpose:
+ *      Single_add: add two single precision values.
+ *
+ *  External Interfaces:
+ *      sgl_fadd(leftptr, rightptr, 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_add: add two single precision values.
+ */
+int
+sgl_fadd(
+    sgl_floating_point *leftptr,
+    sgl_floating_point *rightptr,
+    sgl_floating_point *dstptr,
+    unsigned int *status)
+    {
+    register unsigned int left, right, result, extent;
+    register unsigned int signless_upper_left, signless_upper_right, save;
+    
+    
+    register int result_exponent, right_exponent, diff_exponent;
+    register int sign_save, jumpsize;
+    register boolean inexact = FALSE;
+    register boolean underflowtrap;
+        
+    /* Create local copies of the numbers */
+    left = *leftptr;
+    right = *rightptr;
+
+    /* A zero "save" helps discover equal operands (for later),  *
+     * and is used in swapping operands (if needed).             */
+    Sgl_xortointp1(left,right,/*to*/save);
+
+    /*
+     * check first operand for NaN's or infinity
+     */
+    if ((result_exponent = Sgl_exponent(left)) == SGL_INFINITY_EXPONENT)
+        {
+        if (Sgl_iszero_mantissa(left)) 
+            {
+            if (Sgl_isnotnan(right)) 
+                {
+                if (Sgl_isinfinity(right) && save!=0) 
+                    {
+                    /* 
+                     * invalid since operands are opposite signed infinity's
+                     */
+                    if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+                    Set_invalidflag();
+                    Sgl_makequietnan(result);
+                    *dstptr = result;
+                    return(NOEXCEPTION);
+                    }
+                /*
+                 * return infinity
+                 */
+                *dstptr = left;
+                return(NOEXCEPTION);
+                }
+            }
+        else 
+            {
+            /*
+             * is NaN; signaling or quiet?
+             */
+            if (Sgl_isone_signaling(left)) 
+                {
+                /* trap if INVALIDTRAP enabled */
+                if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+                /* make NaN quiet */
+                Set_invalidflag();
+                Sgl_set_quiet(left);
+                }
+            /* 
+             * is second operand a signaling NaN? 
+             */
+            else if (Sgl_is_signalingnan(right)) 
+                {
+                /* trap if INVALIDTRAP enabled */
+                if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+                /* make NaN quiet */
+                Set_invalidflag();
+                Sgl_set_quiet(right);
+                *dstptr = right;
+                return(NOEXCEPTION);
+                }
+            /*
+             * return quiet NaN
+             */
+            *dstptr = left;
+            return(NOEXCEPTION);
+            }
+        } /* End left NaN or Infinity processing */
+    /*
+     * check second operand for NaN's or infinity
+     */
+    if (Sgl_isinfinity_exponent(right)) 
+        {
+        if (Sgl_iszero_mantissa(right)) 
+            {
+            /* return infinity */
+            *dstptr = right;
+            return(NOEXCEPTION);
+            }
+        /*
+         * is NaN; signaling or quiet?
+         */
+        if (Sgl_isone_signaling(right)) 
+            {
+            /* trap if INVALIDTRAP enabled */
+            if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+            /* make NaN quiet */
+            Set_invalidflag();
+            Sgl_set_quiet(right);
+            }
+        /*
+         * return quiet NaN
+         */
+        *dstptr = right;
+        return(NOEXCEPTION);
+        } /* End right NaN or Infinity processing */
+
+    /* Invariant: Must be dealing with finite numbers */
+
+    /* Compare operands by removing the sign */
+    Sgl_copytoint_exponentmantissa(left,signless_upper_left);
+    Sgl_copytoint_exponentmantissa(right,signless_upper_right);
+
+    /* sign difference selects add or sub operation. */
+    if(Sgl_ismagnitudeless(signless_upper_left,signless_upper_right))
+        {
+        /* Set the left operand to the larger one by XOR swap *
+         *  First finish the first word using "save"          */
+        Sgl_xorfromintp1(save,right,/*to*/right);
+        Sgl_xorfromintp1(save,left,/*to*/left);
+        result_exponent = Sgl_exponent(left);
+        }
+    /* Invariant:  left is not smaller than right. */ 
+
+    if((right_exponent = Sgl_exponent(right)) == 0)
+        {
+        /* Denormalized operands.  First look for zeroes */
+        if(Sgl_iszero_mantissa(right)) 
+            {
+            /* right is zero */
+            if(Sgl_iszero_exponentmantissa(left))
+                {
+                /* Both operands are zeros */
+                if(Is_rounding_mode(ROUNDMINUS))
+                    {
+                    Sgl_or_signs(left,/*with*/right);
+                    }
+                else
+                    {
+                    Sgl_and_signs(left,/*with*/right);
+                    }
+                }
+            else 
+                {
+                /* Left is not a zero and must be the result.  Trapped
+                 * underflows are signaled if left is denormalized.  Result
+                 * is always exact. */
+                if( (result_exponent == 0) && Is_underflowtrap_enabled() )
+                    {
+                    /* need to normalize results mantissa */
+                    sign_save = Sgl_signextendedsign(left);
+                    Sgl_leftshiftby1(left);
+                    Sgl_normalize(left,result_exponent);
+                    Sgl_set_sign(left,/*using*/sign_save);
+                    Sgl_setwrapped_exponent(left,result_exponent,unfl);
+                    *dstptr = left;
+                    return(UNDERFLOWEXCEPTION);
+                    }
+                }
+            *dstptr = left;
+            return(NOEXCEPTION);
+            }
+
+        /* Neither are zeroes */
+        Sgl_clear_sign(right);  /* Exponent is already cleared */
+        if(result_exponent == 0 )
+            {
+            /* Both operands are denormalized.  The result must be exact
+             * and is simply calculated.  A sum could become normalized and a
+             * difference could cancel to a true zero. */
+            if( (/*signed*/int) save < 0 )
+                {
+                Sgl_subtract(left,/*minus*/right,/*into*/result);
+                if(Sgl_iszero_mantissa(result))
+                    {
+                    if(Is_rounding_mode(ROUNDMINUS))
+                        {
+                        Sgl_setone_sign(result);
+                        }
+                    else
+                        {
+                        Sgl_setzero_sign(result);
+                        }
+                    *dstptr = result;
+                    return(NOEXCEPTION);
+                    }
+                }
+            else
+                {
+                Sgl_addition(left,right,/*into*/result);
+                if(Sgl_isone_hidden(result))
+                    {
+                    *dstptr = result;
+                    return(NOEXCEPTION);
+                    }
+                }
+            if(Is_underflowtrap_enabled())
+                {
+                /* need to normalize result */
+                sign_save = Sgl_signextendedsign(result);
+                Sgl_leftshiftby1(result);
+                Sgl_normalize(result,result_exponent);
+                Sgl_set_sign(result,/*using*/sign_save);
+                Sgl_setwrapped_exponent(result,result_exponent,unfl);
+                *dstptr = result;
+                return(UNDERFLOWEXCEPTION);
+                }
+            *dstptr = result;
+            return(NOEXCEPTION);
+            }
+        right_exponent = 1;     /* Set exponent to reflect different bias
+                                 * with denomalized numbers. */
+        }
+    else
+        {
+        Sgl_clear_signexponent_set_hidden(right);
+        }
+    Sgl_clear_exponent_set_hidden(left);
+    diff_exponent = result_exponent - right_exponent;
+
+    /* 
+     * Special case alignment of operands that would force alignment 
+     * beyond the extent of the extension.  A further optimization
+     * could special case this but only reduces the path length for this
+     * infrequent case.
+     */
+    if(diff_exponent > SGL_THRESHOLD)
+        {
+        diff_exponent = SGL_THRESHOLD;
+        }
+    
+    /* Align right operand by shifting to right */
+    Sgl_right_align(/*operand*/right,/*shifted by*/diff_exponent,
+     /*and lower to*/extent);
+
+    /* Treat sum and difference of the operands separately. */
+    if( (/*signed*/int) save < 0 )
+        {
+        /*
+         * Difference of the two operands.  Their can be no overflow.  A
+         * borrow can occur out of the hidden bit and force a post
+         * normalization phase.
+         */
+        Sgl_subtract_withextension(left,/*minus*/right,/*with*/extent,/*into*/result);
+        if(Sgl_iszero_hidden(result))
+            {
+            /* Handle normalization */
+            /* A straight foward algorithm would now shift the result
+             * and extension left until the hidden bit becomes one.  Not
+             * all of the extension bits need participate in the shift.
+             * Only the two most significant bits (round and guard) are
+             * needed.  If only a single shift is needed then the guard
+             * bit becomes a significant low order bit and the extension
+             * must participate in the rounding.  If more than a single 
+             * shift is needed, then all bits to the right of the guard 
+             * bit are zeros, and the guard bit may or may not be zero. */
+            sign_save = Sgl_signextendedsign(result);
+            Sgl_leftshiftby1_withextent(result,extent,result);
+
+            /* Need to check for a zero result.  The sign and exponent
+             * fields have already been zeroed.  The more efficient test
+             * of the full object can be used.
+             */
+            if(Sgl_iszero(result))
+                /* Must have been "x-x" or "x+(-x)". */
+                {
+                if(Is_rounding_mode(ROUNDMINUS)) Sgl_setone_sign(result);
+                *dstptr = result;
+                return(NOEXCEPTION);
+                }
+            result_exponent--;
+            /* Look to see if normalization is finished. */
+            if(Sgl_isone_hidden(result))
+                {
+                if(result_exponent==0)
+                    {
+                    /* Denormalized, exponent should be zero.  Left operand *
+                     * was normalized, so extent (guard, round) was zero    */
+                    goto underflow;
+                    }
+                else
+                    {
+                    /* No further normalization is needed. */
+                    Sgl_set_sign(result,/*using*/sign_save);
+                    Ext_leftshiftby1(extent);
+                    goto round;
+                    }
+                }
+
+            /* Check for denormalized, exponent should be zero.  Left    * 
+             * operand was normalized, so extent (guard, round) was zero */
+            if(!(underflowtrap = Is_underflowtrap_enabled()) &&
+               result_exponent==0) goto underflow;
+
+            /* Shift extension to complete one bit of normalization and
+             * update exponent. */
+            Ext_leftshiftby1(extent);
+
+            /* Discover first one bit to determine shift amount.  Use a
+             * modified binary search.  We have already shifted the result
+             * one position right and still not found a one so the remainder
+             * of the extension must be zero and simplifies rounding. */
+            /* Scan bytes */
+            while(Sgl_iszero_hiddenhigh7mantissa(result))
+                {
+                Sgl_leftshiftby8(result);
+                if((result_exponent -= 8) <= 0  && !underflowtrap)
+                    goto underflow;
+                }
+            /* Now narrow it down to the nibble */
+            if(Sgl_iszero_hiddenhigh3mantissa(result))
+                {
+                /* The lower nibble contains the normalizing one */
+                Sgl_leftshiftby4(result);
+                if((result_exponent -= 4) <= 0 && !underflowtrap)
+                    goto underflow;
+                }
+            /* Select case were first bit is set (already normalized)
+             * otherwise select the proper shift. */
+            if((jumpsize = Sgl_hiddenhigh3mantissa(result)) > 7)
+                {
+                /* Already normalized */
+                if(result_exponent <= 0) goto underflow;
+                Sgl_set_sign(result,/*using*/sign_save);
+                Sgl_set_exponent(result,/*using*/result_exponent);
+                *dstptr = result;
+                return(NOEXCEPTION);
+                }
+            Sgl_sethigh4bits(result,/*using*/sign_save);
+            switch(jumpsize) 
+                {
+                case 1:
+                    {
+                    Sgl_leftshiftby3(result);
+                    result_exponent -= 3;
+                    break;
+                    }
+                case 2:
+                case 3:
+                    {
+                    Sgl_leftshiftby2(result);
+                    result_exponent -= 2;
+                    break;
+                    }
+                case 4:
+                case 5:
+                case 6:
+                case 7:
+                    {
+                    Sgl_leftshiftby1(result);
+                    result_exponent -= 1;
+                    break;
+                    }
+                }
+            if(result_exponent > 0) 
+                {
+                Sgl_set_exponent(result,/*using*/result_exponent);
+                *dstptr = result;
+                return(NOEXCEPTION); /* Sign bit is already set */
+                }
+            /* Fixup potential underflows */
+          underflow:
+            if(Is_underflowtrap_enabled())
+                {
+                Sgl_set_sign(result,sign_save);
+                Sgl_setwrapped_exponent(result,result_exponent,unfl);
+                *dstptr = result;
+                /* inexact = FALSE; */
+                return(UNDERFLOWEXCEPTION);
+                }
+            /* 
+             * Since we cannot get an inexact denormalized result,
+             * we can now return.
+             */
+            Sgl_right_align(result,/*by*/(1-result_exponent),extent);
+            Sgl_clear_signexponent(result);
+            Sgl_set_sign(result,sign_save);
+            *dstptr = result;
+            return(NOEXCEPTION);
+            } /* end if(hidden...)... */
+        /* Fall through and round */
+        } /* end if(save < 0)... */
+    else 
+        {
+        /* Add magnitudes */
+        Sgl_addition(left,right,/*to*/result);
+        if(Sgl_isone_hiddenoverflow(result))
+            {
+            /* Prenormalization required. */
+            Sgl_rightshiftby1_withextent(result,extent,extent);
+            Sgl_arithrightshiftby1(result);
+            result_exponent++;
+            } /* end if hiddenoverflow... */
+        } /* end else ...add magnitudes... */
+    
+    /* Round the result.  If the extension is all zeros,then the result is
+     * exact.  Otherwise round in the correct direction.  No underflow is
+     * possible. If a postnormalization is necessary, then the mantissa is
+     * all zeros so no shift is needed. */
+  round:
+    if(Ext_isnotzero(extent))
+        {
+        inexact = TRUE;
+        switch(Rounding_mode())
+            {
+            case ROUNDNEAREST: /* The default. */
+            if(Ext_isone_sign(extent))
+                {
+                /* at least 1/2 ulp */
+                if(Ext_isnotzero_lower(extent)  ||
+                  Sgl_isone_lowmantissa(result))
+                    {
+                    /* either exactly half way and odd or more than 1/2ulp */
+                    Sgl_increment(result);
+                    }
+                }
+            break;
+
+            case ROUNDPLUS:
+            if(Sgl_iszero_sign(result))
+                {
+                /* Round up positive results */
+                Sgl_increment(result);
+                }
+            break;
+            
+            case ROUNDMINUS:
+            if(Sgl_isone_sign(result))
+                {
+                /* Round down negative results */
+                Sgl_increment(result);
+                }
+            
+            case ROUNDZERO:;
+            /* truncate is simple */
+            } /* end switch... */
+        if(Sgl_isone_hiddenoverflow(result)) result_exponent++;
+        }
+    if(result_exponent == SGL_INFINITY_EXPONENT)
+        {
+        /* Overflow */
+        if(Is_overflowtrap_enabled())
+            {
+            Sgl_setwrapped_exponent(result,result_exponent,ovfl);
+            *dstptr = result;
+            if (inexact)
+                if (Is_inexacttrap_enabled())
+                    return(OVERFLOWEXCEPTION | INEXACTEXCEPTION);
+                else Set_inexactflag();
+            return(OVERFLOWEXCEPTION);
+            }
+        else
+            {
+            Set_overflowflag();
+            inexact = TRUE;
+            Sgl_setoverflow(result);
+            }
+        }
+    else Sgl_set_exponent(result,result_exponent);
+    *dstptr = result;
+    if(inexact) 
+        if(Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
+        else Set_inexactflag();
+    return(NOEXCEPTION);
+    }