[sim]

	* rx: New directory.
	* configure.ac: Add entry for Renesas RX.
	* configure: Regenerate.

[include/gdb]
	* sim-rx.h: New.

1 files changed, 791 insertions, 0 deletions

diff --git a/sim/rx/fpu.c b/sim/rx/fpu.c
new file mode 100644
index 0000000..391a6a5
--- /dev/null
+++ b/sim/rx/fpu.c
@@ -0,0 +1,791 @@
+/* fpu.c --- FPU emulator for stand-alone RX simulator.
+
+Copyright (C) 2008, 2009 Free Software Foundation, Inc.
+Contributed by Red Hat, Inc.
+
+This file is part of the GNU simulators.
+
+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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "cpu.h"
+#include "fpu.h"
+
+/* FPU encodings are as follows:
+
+   S EXPONENT MANTISSA
+   1 12345678 12345678901234567890123
+
+   0 00000000 00000000000000000000000	+0
+   1 00000000 00000000000000000000000	-0
+
+   X 00000000 00000000000000000000001	Denormals
+   X 00000000 11111111111111111111111
+ 
+   X 00000001 XXXXXXXXXXXXXXXXXXXXXXX	Normals
+   X 11111110 XXXXXXXXXXXXXXXXXXXXXXX
+
+   0 11111111 00000000000000000000000	+Inf
+   1 11111111 00000000000000000000000	-Inf
+
+   X 11111111 0XXXXXXXXXXXXXXXXXXXXXX	SNaN (X != 0)
+   X 11111111 1XXXXXXXXXXXXXXXXXXXXXX	QNaN (X != 0)
+
+*/
+
+#define trace 0
+#define tprintf if (trace) printf
+
+/* Some magic numbers.  */
+#define PLUS_MAX   0x7f7fffffUL
+#define MINUS_MAX  0xff7fffffUL
+#define PLUS_INF   0x7f800000UL
+#define MINUS_INF  0xff800000UL
+#define PLUS_ZERO  0x00000000UL
+#define MINUS_ZERO 0x80000000UL
+
+#define FP_RAISE(e) fp_raise(FPSWBITS_C##e)
+static void
+fp_raise (int mask)
+{
+  regs.r_fpsw |= mask;
+  if (mask != FPSWBITS_CE)
+    {
+      if (regs.r_fpsw & (mask << FPSW_CESH))
+	regs.r_fpsw |= (mask << FPSW_CFSH);
+      if (regs.r_fpsw & FPSWBITS_FMASK)
+	regs.r_fpsw |= FPSWBITS_FSUM;
+      else
+	regs.r_fpsw &= ~FPSWBITS_FSUM;
+    }
+}
+
+/* We classify all numbers as one of these.  They correspond to the
+   rows/colums in the exception tables.  */
+typedef enum {
+  FP_NORMAL,
+  FP_PZERO,
+  FP_NZERO,
+  FP_PINFINITY,
+  FP_NINFINITY,
+  FP_DENORMAL,
+  FP_QNAN,
+  FP_SNAN
+} FP_Type;
+
+#if defined DEBUG0
+static const char *fpt_names[] = {
+  "Normal", "+0", "-0", "+Inf", "-Inf", "Denormal", "QNaN", "SNaN"
+};
+#endif
+
+#define EXP_BIAS  127
+#define EXP_ZERO -127
+#define EXP_INF   128
+
+#define MANT_BIAS 0x00080000UL
+
+typedef struct {
+  int exp;
+  unsigned int mant; /* 24 bits */
+  char type;
+  char sign;
+  fp_t orig_value;
+} FP_Parts;
+
+static void
+fp_explode (fp_t f, FP_Parts *p)
+{
+  int exp, mant, sign;
+
+  exp = ((f & 0x7f800000UL) >> 23);
+  mant = f & 0x007fffffUL;
+  sign = f & 0x80000000UL;
+  /*printf("explode: %08x %x %2x %6x\n", f, sign, exp, mant);*/
+
+  p->sign = sign ? -1 : 1;
+  p->exp = exp - EXP_BIAS;
+  p->orig_value = f;
+  p->mant = mant | 0x00800000UL;
+
+  if (p->exp == EXP_ZERO)
+    {
+      if (regs.r_fpsw & FPSWBITS_DN)
+	mant = 0;
+      if (mant)
+	p->type = FP_DENORMAL;
+      else
+	{
+	  p->mant = 0;
+	  p->type = sign ? FP_NZERO : FP_PZERO;
+	}
+    }
+  else if (p->exp == EXP_INF)
+    {
+      if (mant == 0)
+	p->type = sign ? FP_NINFINITY : FP_PINFINITY;
+      else if (mant & 0x00400000UL)
+	p->type = FP_QNAN;
+      else
+	p->type = FP_SNAN;
+    }
+  else
+    p->type = FP_NORMAL;
+}
+
+static fp_t
+fp_implode (FP_Parts *p)
+{
+  int exp, mant;
+
+  exp = p->exp + EXP_BIAS;
+  mant = p->mant;
+  /*printf("implode: exp %d mant 0x%x\n", exp, mant);*/
+  if (p->type == FP_NORMAL)
+    {
+      while (mant
+	     && exp > 0
+	     && mant < 0x00800000UL)
+	{
+	  mant <<= 1;
+	  exp --;
+	}
+      while (mant > 0x00ffffffUL)
+	{
+	  mant >>= 1;
+	  exp ++;
+	}
+      if (exp < 0)
+	{
+	  /* underflow */
+	  exp = 0;
+	  mant = 0;
+	  FP_RAISE (E);
+	}
+      if (exp >= 255)
+	{
+	  /* overflow */
+	  exp = 255;
+	  mant = 0;
+	  FP_RAISE (O);
+	}
+    }
+  mant &= 0x007fffffUL;
+  exp &= 0xff;
+  mant |= exp << 23;
+  if (p->sign < 0)
+    mant |= 0x80000000UL;
+
+  return mant;
+}
+
+typedef union {
+  unsigned long long ll;
+  double d;
+} U_d_ll;
+
+static int checked_format = 0;
+
+/* We assume a double format like this:
+   S[1] E[11] M[52]
+*/
+
+static double
+fp_to_double (FP_Parts *p)
+{
+  U_d_ll u;
+
+  if (!checked_format)
+    {
+      u.d = 1.5;
+      if (u.ll != 0x3ff8000000000000ULL)
+	abort ();
+      u.d = -225;
+      if (u.ll != 0xc06c200000000000ULL)
+	abort ();
+      u.d = 10.1;
+      if (u.ll != 0x4024333333333333ULL)
+	abort ();
+      checked_format = 1;
+    }
+
+  u.ll = 0;
+  if (p->sign < 0)
+    u.ll |= (1ULL << 63);
+  /* Make sure a zero encoding stays a zero.  */
+  if (p->exp != -EXP_BIAS)
+    u.ll |= ((unsigned long long)p->exp + 1023ULL) << 52;
+  u.ll |= (unsigned long long) (p->mant & 0x007fffffUL) << (52 - 23);
+  return u.d;
+}
+
+static void
+double_to_fp (double d, FP_Parts *p)
+{
+  int exp;
+  U_d_ll u;
+  int sign;
+
+  u.d = d;
+
+  sign = (u.ll & 0x8000000000000000ULL) ? 1 : 0;
+  exp = u.ll >> 52;
+  exp = (exp & 0x7ff);
+
+  if (exp == 0)
+    {
+      /* A generated denormal should show up as an underflow, not
+	 here.  */
+      if (sign)
+	fp_explode (MINUS_ZERO, p);
+      else
+	fp_explode (PLUS_ZERO, p);
+      return;
+    }
+
+  exp = exp - 1023;
+  if ((exp + EXP_BIAS) > 254)
+    {
+      FP_RAISE (O);
+      switch (regs.r_fpsw & FPSWBITS_RM)
+	{
+	case FPRM_NEAREST:
+	  if (sign)
+	    fp_explode (MINUS_INF, p);
+	  else
+	    fp_explode (PLUS_INF, p);
+	  break;
+	case FPRM_ZERO:
+	  if (sign)
+	    fp_explode (MINUS_MAX, p);
+	  else
+	    fp_explode (PLUS_MAX, p);
+	  break;
+	case FPRM_PINF:
+	  if (sign)
+	    fp_explode (MINUS_MAX, p);
+	  else
+	    fp_explode (PLUS_INF, p);
+	  break;
+	case FPRM_NINF:
+	  if (sign)
+	    fp_explode (MINUS_INF, p);
+	  else
+	    fp_explode (PLUS_MAX, p);
+	  break;
+	}
+      return;
+    }
+  if ((exp + EXP_BIAS) < 1)
+    {
+      if (sign)
+	fp_explode (MINUS_ZERO, p);
+      else
+	fp_explode (PLUS_ZERO, p);
+      FP_RAISE (U);
+    }
+
+  p->sign = sign ? -1 : 1;
+  p->exp = exp;
+  p->mant = u.ll >> (52-23) & 0x007fffffUL;
+  p->mant |= 0x00800000UL;
+  p->type = FP_NORMAL;
+
+  if (u.ll & 0x1fffffffULL)
+    {
+      switch (regs.r_fpsw & FPSWBITS_RM)
+	{
+	case FPRM_NEAREST:
+	  if (u.ll & 0x10000000ULL)
+	    p->mant ++;
+	  break;
+	case FPRM_ZERO:
+	  break;
+	case FPRM_PINF:
+	  if (sign == 1)
+	    p->mant ++;
+	  break;
+	case FPRM_NINF:
+	  if (sign == -1)
+	    p->mant ++;
+	  break;
+	}
+      FP_RAISE (X);
+    }
+
+}
+
+typedef enum {
+  eNR,		/* Use the normal result.  */
+  ePZ, eNZ,	/* +- zero */
+  eSZ,		/* signed zero - XOR signs of ops together.  */
+  eRZ,		/* +- zero depending on rounding mode.  */
+  ePI, eNI,	/* +- Infinity */
+  eSI,		/* signed infinity - XOR signs of ops together.  */
+  eQN, eSN,	/* Quiet/Signalling NANs */
+  eIn,		/* Invalid.  */
+  eUn,		/* Unimplemented.  */
+  eDZ,		/* Divide-by-zero.  */
+  eLT,		/* less than */
+  eGT,		/* greater than */
+  eEQ,		/* equal to */
+} FP_ExceptionCases;
+
+#if defined DEBUG0
+static const char *ex_names[] = {
+  "NR", "PZ", "NZ", "SZ", "RZ", "PI", "NI", "SI", "QN", "SN", "IN", "Un", "DZ", "LT", "GT", "EQ"
+};
+#endif
+
+/* This checks for all exceptional cases (not all FP exceptions) and
+   returns TRUE if it is providing the result in *c.  If it returns
+   FALSE, the caller should do the "normal" operation.  */
+int
+check_exceptions (FP_Parts *a, FP_Parts *b, fp_t *c,
+		  FP_ExceptionCases ex_tab[5][5], 
+		  FP_ExceptionCases *case_ret)
+{
+  FP_ExceptionCases fpec;
+
+  if (a->type == FP_SNAN
+      || b->type == FP_SNAN)
+    fpec = eIn;
+  else if (a->type == FP_QNAN
+	   || b->type == FP_QNAN)
+    fpec = eQN;
+  else if (a->type == FP_DENORMAL
+	   || b->type == FP_DENORMAL)
+    fpec = eUn;
+  else
+    fpec = ex_tab[(int)(a->type)][(int)(b->type)];
+
+  /*printf("%s %s -> %s\n", fpt_names[(int)(a->type)], fpt_names[(int)(b->type)], ex_names[(int)(fpec)]);*/
+
+  if (case_ret)
+    *case_ret = fpec;
+
+  switch (fpec)
+    {
+    case eNR:	/* Use the normal result.  */
+      return 0;
+
+    case ePZ:	/* + zero */
+      *c = 0x00000000;
+      return 1;
+
+    case eNZ:	/* - zero */
+      *c = 0x80000000;
+      return 1;
+
+    case eSZ:	/* signed zero */
+      *c = (a->sign == b->sign) ? PLUS_ZERO : MINUS_ZERO;
+      return 1;
+
+    case eRZ:	/* +- zero depending on rounding mode.  */
+      if ((regs.r_fpsw & FPSWBITS_RM) == FPRM_NINF)
+	*c = 0x80000000;
+      else
+	*c = 0x00000000;
+      return 1;
+
+    case ePI:	/* + Infinity */
+      *c = 0x7F800000;
+      return 1;
+
+    case eNI:	/* - Infinity */
+      *c = 0xFF800000;
+      return 1;
+
+    case eSI:	/* sign Infinity */
+      *c = (a->sign == b->sign) ? PLUS_INF : MINUS_INF;
+      return 1;
+
+    case eQN:	/* Quiet NANs */
+      if (a->type == FP_QNAN)
+	*c = a->orig_value;
+      else
+	*c = b->orig_value;
+      return 1;
+
+    case eSN:	/* Signalling NANs */
+      if (a->type == FP_SNAN)
+	*c = a->orig_value;
+      else
+	*c = b->orig_value;
+      FP_RAISE (V);
+      return 1;
+
+    case eIn:	/* Invalid.  */
+      FP_RAISE (V);
+      if (a->type == FP_SNAN)
+	*c = a->orig_value | 0x00400000;
+      else if  (a->type == FP_SNAN)
+	*c = b->orig_value | 0x00400000;
+      else
+	*c = 0x7fc00000;
+      return 1;
+
+    case eUn:	/* Unimplemented.  */
+      FP_RAISE (E);
+      return 1;
+
+    case eDZ:	/* Division-by-zero.  */
+      *c = (a->sign == b->sign) ? PLUS_INF : MINUS_INF;
+      FP_RAISE (Z);
+      return 1;
+
+    default:
+      return 0;
+    }
+}
+
+#define CHECK_EXCEPTIONS(FPPa, FPPb, fpc, ex_tab) \
+  if (check_exceptions (&FPPa, &FPPb, &fpc, ex_tab, 0))	\
+    return fpc;
+
+/* For each operation, we have two tables of how nonnormal cases are
+   handled.  The DN=0 case is first, followed by the DN=1 case, with
+   each table using the following layout: */
+
+static FP_ExceptionCases ex_add_tab[5][5] = {
+  /* N   +0   -0   +In  -In */
+  { eNR, eNR, eNR, ePI, eNI }, /* Normal */
+  { eNR, ePZ, eRZ, ePI, eNI }, /* +0   */
+  { eNR, eRZ, eNZ, ePI, eNI }, /* -0   */
+  { ePI, ePI, ePI, ePI, eIn }, /* +Inf */
+  { eNI, eNI, eNI, eIn, eNI }, /* -Inf */
+};
+
+fp_t
+rxfp_add (fp_t fa, fp_t fb)
+{
+  FP_Parts a, b, c;
+  fp_t rv;
+  double da, db;
+
+  fp_explode (fa, &a);
+  fp_explode (fb, &b);
+  CHECK_EXCEPTIONS (a, b, rv, ex_add_tab);
+
+  da = fp_to_double (&a);
+  db = fp_to_double (&b);
+  tprintf("%g + %g = %g\n", da, db, da+db);
+
+  double_to_fp (da+db, &c);
+  rv = fp_implode (&c);
+  return rv;
+}
+
+static FP_ExceptionCases ex_sub_tab[5][5] = {
+  /* N   +0   -0   +In  -In */
+  { eNR, eNR, eNR, eNI, ePI }, /* Normal */
+  { eNR, eRZ, ePZ, eNI, ePI }, /* +0   */
+  { eNR, eNZ, eRZ, eNI, ePI }, /* -0   */
+  { ePI, ePI, ePI, eIn, ePI }, /* +Inf */
+  { eNI, eNI, eNI, eNI, eIn }, /* -Inf */
+};
+
+fp_t
+rxfp_sub (fp_t fa, fp_t fb)
+{
+  FP_Parts a, b, c;
+  fp_t rv;
+  double da, db;
+
+  fp_explode (fa, &a);
+  fp_explode (fb, &b);
+  CHECK_EXCEPTIONS (a, b, rv, ex_sub_tab);
+
+  da = fp_to_double (&a);
+  db = fp_to_double (&b);
+  tprintf("%g - %g = %g\n", da, db, da-db);
+
+  double_to_fp (da-db, &c);
+  rv = fp_implode (&c);
+
+  return rv;
+}
+
+static FP_ExceptionCases ex_mul_tab[5][5] = {
+  /* N   +0   -0   +In  -In */
+  { eNR, eNR, eNR, eSI, eSI }, /* Normal */
+  { eNR, ePZ, eNZ, eIn, eIn }, /* +0   */
+  { eNR, eNZ, ePZ, eIn, eIn }, /* -0   */
+  { eSI, eIn, eIn, ePI, eNI }, /* +Inf */
+  { eSI, eIn, eIn, eNI, ePI }, /* -Inf */
+};
+
+fp_t
+rxfp_mul (fp_t fa, fp_t fb)
+{
+  FP_Parts a, b, c;
+  fp_t rv;
+  double da, db;
+
+  fp_explode (fa, &a);
+  fp_explode (fb, &b);
+  CHECK_EXCEPTIONS (a, b, rv, ex_mul_tab);
+
+  da = fp_to_double (&a);
+  db = fp_to_double (&b);
+  tprintf("%g x %g = %g\n", da, db, da*db);
+
+  double_to_fp (da*db, &c);
+  rv = fp_implode (&c);
+
+  return rv;
+}
+
+static FP_ExceptionCases ex_div_tab[5][5] = {
+  /* N   +0   -0   +In  -In */
+  { eNR, eDZ, eDZ, eSZ, eSZ }, /* Normal */
+  { eSZ, eIn, eIn, ePZ, eNZ }, /* +0   */
+  { eSZ, eIn, eIn, eNZ, ePZ }, /* -0   */
+  { eSI, ePI, eNI, eIn, eIn }, /* +Inf */
+  { eSI, eNI, ePI, eIn, eIn }, /* -Inf */
+};
+
+fp_t
+rxfp_div (fp_t fa, fp_t fb)
+{
+  FP_Parts a, b, c;
+  fp_t rv;
+  double da, db;
+
+  fp_explode (fa, &a);
+  fp_explode (fb, &b);
+  CHECK_EXCEPTIONS (a, b, rv, ex_div_tab);
+
+  da = fp_to_double (&a);
+  db = fp_to_double (&b);
+  tprintf("%g / %g = %g\n", da, db, da/db);
+
+  double_to_fp (da/db, &c);
+  rv = fp_implode (&c);
+
+  return rv;
+}
+
+static FP_ExceptionCases ex_cmp_tab[5][5] = {
+  /* N   +0   -0   +In  -In */
+  { eNR, eNR, eNR, eLT, eGT }, /* Normal */
+  { eNR, eEQ, eEQ, eLT, eGT }, /* +0   */
+  { eNR, eEQ, eEQ, eLT, eGT }, /* -0   */
+  { eGT, eGT, eGT, eEQ, eGT }, /* +Inf */
+  { eLT, eLT, eLT, eLT, eEQ }, /* -Inf */
+};
+
+void
+rxfp_cmp (fp_t fa, fp_t fb)
+{
+  FP_Parts a, b;
+  fp_t c;
+  FP_ExceptionCases reason;
+  int flags = 0;
+  double da, db;
+
+  fp_explode (fa, &a);
+  fp_explode (fb, &b);
+
+  if (check_exceptions (&a, &b, &c, ex_cmp_tab, &reason))
+    {
+      if (reason == eQN)
+	{
+	  /* Special case - incomparable.  */
+	  set_flags (FLAGBIT_Z | FLAGBIT_S | FLAGBIT_O, FLAGBIT_O);
+	  return;
+	}
+      return;
+    }
+
+  switch (reason)
+    {
+    case eEQ:
+      flags = FLAGBIT_Z;
+      break;
+    case eLT:
+      flags = FLAGBIT_S;
+      break;
+    case eGT:
+      flags = 0;
+      break;
+    case eNR:
+      da = fp_to_double (&a);
+      db = fp_to_double (&b);
+      tprintf("fcmp: %g cmp %g\n", da, db);
+      if (da < db)
+	flags = FLAGBIT_S;
+      else if (da == db)
+	flags = FLAGBIT_Z;
+      else
+	flags = 0;
+      break;
+    default:
+      abort();
+    }
+
+  set_flags (FLAGBIT_Z | FLAGBIT_S | FLAGBIT_O, flags);
+}
+
+long
+rxfp_ftoi (fp_t fa, int round_mode)
+{
+  FP_Parts a;
+  fp_t rv;
+  int sign;
+  int whole_bits, frac_bits;
+
+  fp_explode (fa, &a);
+  sign = fa & 0x80000000UL;
+
+  switch (a.type)
+    {
+    case FP_NORMAL:
+      break;
+    case FP_PZERO:
+    case FP_NZERO:
+      return 0;
+    case FP_PINFINITY:
+      FP_RAISE (V);
+      return 0x7fffffffL;
+    case FP_NINFINITY:
+      FP_RAISE (V);
+      return 0x80000000L;
+    case FP_DENORMAL:
+      FP_RAISE (E);
+      return 0;
+    case FP_QNAN:
+    case FP_SNAN:
+      FP_RAISE (V);
+      return sign ? 0x80000000U : 0x7fffffff;
+    }
+
+  if (a.exp >= 31)
+    {
+      FP_RAISE (V);
+      return sign ? 0x80000000U : 0x7fffffff;
+    }
+
+  a.exp -= 23;
+
+  if (a.exp <= -25)
+    {
+      /* Less than 0.49999 */
+      frac_bits = a.mant;
+      whole_bits = 0;
+    }
+  else if (a.exp < 0)
+    {
+      frac_bits = a.mant << (32 + a.exp);
+      whole_bits = a.mant >> (-a.exp);
+    }
+  else
+    {
+      frac_bits = 0;
+      whole_bits = a.mant << a.exp;
+    }
+
+  if (frac_bits)
+    {
+      switch (round_mode & 3)
+	{
+	case FPRM_NEAREST:
+	  if (frac_bits & 0x80000000UL)
+	    whole_bits ++;
+	  break;
+	case FPRM_ZERO:
+	  break;
+	case FPRM_PINF:
+	  if (!sign)
+	    whole_bits ++;
+	  break;
+	case FPRM_NINF:
+	  if (sign)
+	    whole_bits ++;
+	  break;
+	}
+    }
+
+  rv = sign ? -whole_bits : whole_bits;
+  
+  return rv;
+}
+
+fp_t
+rxfp_itof (long fa, int round_mode)
+{
+  fp_t rv;
+  int sign = 0;
+  unsigned int frac_bits;
+  volatile unsigned int whole_bits;
+  FP_Parts a;
+
+  if (fa == 0)
+    return PLUS_ZERO;
+
+  if (fa < 0)
+    {
+      fa = -fa;
+      sign = 1;
+      a.sign = -1;
+    }
+  else
+    a.sign = 1;
+
+  whole_bits = fa;
+  a.exp = 31;
+
+  while (! (whole_bits & 0x80000000UL))
+    {
+      a.exp --;
+      whole_bits <<= 1;
+    }
+  frac_bits = whole_bits & 0xff;
+  whole_bits = whole_bits >> 8;
+
+  if (frac_bits)
+    {
+      /* We must round */
+      switch (round_mode & 3)
+	{
+	case FPRM_NEAREST:
+	  if (frac_bits & 0x80)
+	    whole_bits ++;
+	  break;
+	case FPRM_ZERO:
+	  break;
+	case FPRM_PINF:
+	  if (!sign)
+	    whole_bits ++;
+	  break;
+	case FPRM_NINF:
+	  if (sign)
+	    whole_bits ++;
+	  break;
+	}
+    }
+
+  a.mant = whole_bits;
+  if (whole_bits & 0xff000000UL)
+    {
+      a.mant >>= 1;
+      a.exp ++;
+    }
+
+  rv = fp_implode (&a);
+  return rv;
+}
+