sim: cgen: add remainder functions (needed for OR1K lf.rem.[sd])

* sim/common/ChangeLog:

2017-12-12  Peter Gavin  <pgavin@gmail.com>
	    Stafford Horne <shorne@gmail.com>

	* cgen-accfp.c (remsf, remdf): New function.
	(cgen_init_accurate_fpu): Add remsf and remdf.
	* cgen-fpu.h (cgen_fp_ops): Add remsf, remdf, remxf and remtf.
	* sim-fpu.c (sim_fpu_rem): New function.
	* sim-fpu.h (sim_fpu_status_invalid_irx): New enum.
	(sim_fpu_rem): New function.
	(sim_fpu_print_status): Add case for sim_fpu_status_invalid_irx.

1 files changed, 86 insertions, 0 deletions

diff --git a/sim/common/sim-fpu.c b/sim/common/sim-fpu.c
index 0d4d08a..8d0fb17 100644
--- a/sim/common/sim-fpu.c
+++ b/sim/common/sim-fpu.c
@@ -1551,6 +1551,89 @@ sim_fpu_div (sim_fpu *f,
 
 
 INLINE_SIM_FPU (int)
+sim_fpu_rem (sim_fpu *f,
+	     const sim_fpu *l,
+	     const sim_fpu *r)
+{
+  if (sim_fpu_is_snan (l))
+    {
+      *f = *l;
+      f->class = sim_fpu_class_qnan;
+      return sim_fpu_status_invalid_snan;
+    }
+  if (sim_fpu_is_snan (r))
+    {
+      *f = *r;
+      f->class = sim_fpu_class_qnan;
+      return sim_fpu_status_invalid_snan;
+    }
+  if (sim_fpu_is_qnan (l))
+    {
+      *f = *l;
+      f->class = sim_fpu_class_qnan;
+      return 0;
+    }
+  if (sim_fpu_is_qnan (r))
+    {
+      *f = *r;
+      f->class = sim_fpu_class_qnan;
+      return 0;
+    }
+  if (sim_fpu_is_infinity (l))
+    {
+      *f = sim_fpu_qnan;
+      return sim_fpu_status_invalid_irx;
+    }
+  if (sim_fpu_is_zero (r))
+    {
+      *f = sim_fpu_qnan;
+      return sim_fpu_status_invalid_div0;
+    }
+  if (sim_fpu_is_zero (l))
+    {
+      *f = *l;
+      return 0;
+    }
+  if (sim_fpu_is_infinity (r))
+    {
+      *f = *l;
+      return 0;
+    }
+  {
+    sim_fpu n, tmp;
+
+    /* Remainder is calculated as l-n*r, where n is l/r rounded to the
+       nearest integer.  The variable n is rounded half even.  */
+
+    sim_fpu_div (&n, l, r);
+    sim_fpu_round_64 (&n, 0, 0);
+
+    if (n.normal_exp < -1) /* If n looks like zero just return l.  */
+      {
+	*f = *l;
+	return 0;
+      }
+    else if (n.class == sim_fpu_class_number
+	     && n.normal_exp <= (NR_FRAC_GUARD)) /* If not too large round.  */
+      do_normal_round (&n, (NR_FRAC_GUARD) - n.normal_exp, sim_fpu_round_near);
+
+    /* Mark 0's as zero so multiply can detect zero.  */
+    if (n.fraction == 0)
+      n.class = sim_fpu_class_zero;
+
+    /* Calculate n*r.  */
+    sim_fpu_mul (&tmp, &n, r);
+    sim_fpu_round_64 (&tmp, 0, 0);
+
+    /* Finally calculate l-n*r.  */
+    sim_fpu_sub (f, l, &tmp);
+
+    return 0;
+  }
+}
+
+
+INLINE_SIM_FPU (int)
 sim_fpu_max (sim_fpu *f,
 	     const sim_fpu *l,
 	     const sim_fpu *r)
@@ -2533,6 +2616,9 @@ sim_fpu_print_status (int status,
 	case sim_fpu_status_invalid_sqrt:
 	  print (arg, "%sSQRT", prefix);
 	  break;
+	case sim_fpu_status_invalid_irx:
+	  print (arg, "%sIRX", prefix);
+	  break;
 	case sim_fpu_status_inexact:
 	  print (arg, "%sX", prefix);
 	  break;