patch-2.3.16 linux/arch/ppc/math-emu/sfp-machine.h

• Lines: 378
• Date: Tue Aug 31 11:36:43 1999
• Orig file: v2.3.15/linux/arch/ppc/math-emu/sfp-machine.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.15/linux/arch/ppc/math-emu/sfp-machine.h linux/arch/ppc/math-emu/sfp-machine.h
@@ -0,0 +1,377 @@
+/* Machine-dependent software floating-point definitions.  PPC version.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If
+   not, write to the Free Software Foundation, Inc.,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  
+
+   Actually, this is a PPC (32bit) version, written based on the
+   i386, sparc, and sparc64 versions, by me, 
+   Peter Maydell (pmaydell@chiark.greenend.org.uk).
+   Comments are by and large also mine, although they may be inaccurate.
+
+   In picking out asm fragments I've gone with the lowest common
+   denominator, which also happens to be the hardware I have :->
+   That is, a SPARC without hardware multiply and divide.
+ */
+
+/* basic word size definitions */
+#define _FP_W_TYPE_SIZE		32
+#define _FP_W_TYPE		unsigned long
+#define _FP_WS_TYPE		signed long
+#define _FP_I_TYPE		long
+
+#define __ll_B			((UWtype) 1 << (W_TYPE_SIZE / 2))
+#define __ll_lowpart(t)		((UWtype) (t) & (__ll_B - 1))
+#define __ll_highpart(t)	((UWtype) (t) >> (W_TYPE_SIZE / 2))
+
+/* You can optionally code some things like addition in asm. For
+ * example, i386 defines __FP_FRAC_ADD_2 as asm. If you don't
+ * then you get a fragment of C code [if you change an #ifdef 0
+ * in op-2.h] or a call to add_ssaaaa (see below).
+ * Good places to look for asm fragments to use are gcc and glibc.
+ * gcc's longlong.h is useful.
+ */
+
+/* We need to know how to multiply and divide. If the host word size
+ * is >= 2*fracbits you can use FP_MUL_MEAT_n_imm(t,R,X,Y) which
+ * codes the multiply with whatever gcc does to 'a * b'.
+ * _FP_MUL_MEAT_n_wide(t,R,X,Y,f) is used when you have an asm 
+ * function that can multiply two 1W values and get a 2W result. 
+ * Otherwise you're stuck with _FP_MUL_MEAT_n_hard(t,R,X,Y) which
+ * does bitshifting to avoid overflow.
+ * For division there is FP_DIV_MEAT_n_imm(t,R,X,Y,f) for word size
+ * >= 2*fracbits, where f is either _FP_DIV_HELP_imm or 
+ * _FP_DIV_HELP_ldiv (see op-1.h).
+ * _FP_DIV_MEAT_udiv() is if you have asm to do 2W/1W => (1W, 1W).
+ * [GCC and glibc have longlong.h which has the asm macro udiv_qrnnd
+ * to do this.]
+ * In general, 'n' is the number of words required to hold the type,
+ * and 't' is either S, D or Q for single/double/quad.
+ *           -- PMM
+ */
+/* Example: SPARC64:
+ * #define _FP_MUL_MEAT_S(R,X,Y)	_FP_MUL_MEAT_1_imm(S,R,X,Y)
+ * #define _FP_MUL_MEAT_D(R,X,Y)	_FP_MUL_MEAT_1_wide(D,R,X,Y,umul_ppmm)
+ * #define _FP_MUL_MEAT_Q(R,X,Y)	_FP_MUL_MEAT_2_wide(Q,R,X,Y,umul_ppmm)
+ *
+ * #define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_imm(S,R,X,Y,_FP_DIV_HELP_imm)
+ * #define _FP_DIV_MEAT_D(R,X,Y)	_FP_DIV_MEAT_1_udiv(D,R,X,Y)
+ * #define _FP_DIV_MEAT_Q(R,X,Y)	_FP_DIV_MEAT_2_udiv_64(Q,R,X,Y)
+ *
+ * Example: i386:
+ * #define _FP_MUL_MEAT_S(R,X,Y)   _FP_MUL_MEAT_1_wide(S,R,X,Y,_i386_mul_32_64)
+ * #define _FP_MUL_MEAT_D(R,X,Y)   _FP_MUL_MEAT_2_wide(D,R,X,Y,_i386_mul_32_64)
+ *
+ * #define _FP_DIV_MEAT_S(R,X,Y)   _FP_DIV_MEAT_1_udiv(S,R,X,Y,_i386_div_64_32)
+ * #define _FP_DIV_MEAT_D(R,X,Y)   _FP_DIV_MEAT_2_udiv_64(D,R,X,Y)
+ */
+
+#define _FP_MUL_MEAT_S(R,X,Y)   _FP_MUL_MEAT_1_wide(S,R,X,Y,umul_ppmm)
+#define _FP_MUL_MEAT_D(R,X,Y)   _FP_MUL_MEAT_2_wide(D,R,X,Y,umul_ppmm)
+
+#define _FP_DIV_MEAT_S(R,X,Y)   _FP_DIV_MEAT_1_udiv(S,R,X,Y)
+#define _FP_DIV_MEAT_D(R,X,Y)   _FP_DIV_MEAT_2_udiv_64(D,R,X,Y)
+
+/* These macros define what NaN looks like. They're supposed to expand to 
+ * a comma-separated set of 32bit unsigned ints that encode NaN.
+ */
+#define _FP_NANFRAC_S		_FP_QNANBIT_S
+#define _FP_NANFRAC_D		_FP_QNANBIT_D, 0
+#define _FP_NANFRAC_Q           _FP_QNANBIT_Q, 0, 0, 0
+
+#define _FP_KEEPNANFRACP 1
+
+/* This macro appears to be called when both X and Y are NaNs, and 
+ * has to choose one and copy it to R. i386 goes for the larger of the
+ * two, sparc64 just picks Y. I don't understand this at all so I'll
+ * go with sparc64 because it's shorter :->   -- PMM 
+ */
+#define _FP_CHOOSENAN(fs, wc, R, X, Y)			\
+  do {							\
+    R##_s = Y##_s;					\
+    _FP_FRAC_COPY_##wc(R,Y);				\
+    R##_c = FP_CLS_NAN;					\
+  } while (0)
+  
+
+extern void fp_unpack_d(long *, unsigned long *, unsigned long *,
+			long *, long *, void *);
+extern int  fp_pack_d(void *, long, unsigned long, unsigned long, long, long);
+extern int  fp_pack_ds(void *, long, unsigned long, unsigned long, long, long);
+
+#define __FP_UNPACK_RAW_1(fs, X, val)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    X##_f = _flo->bits.frac;				\
+    X##_e = _flo->bits.exp;				\
+    X##_s = _flo->bits.sign;				\
+  } while (0)
+
+#define __FP_UNPACK_RAW_2(fs, X, val)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    X##_f0 = _flo->bits.frac0;				\
+    X##_f1 = _flo->bits.frac1;				\
+    X##_e  = _flo->bits.exp;				\
+    X##_s  = _flo->bits.sign;				\
+  } while (0)
+
+#define __FP_UNPACK_S(X,val)		\
+  do {					\
+    __FP_UNPACK_RAW_1(S,X,val);		\
+    _FP_UNPACK_CANONICAL(S,1,X);	\
+  } while (0)
+
+#define __FP_UNPACK_D(X,val)		\
+	fp_unpack_d(&X##_s, &X##_f1, &X##_f0, &X##_e, &X##_c, val)
+
+#define __FP_PACK_RAW_1(fs, val, X)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    _flo->bits.frac = X##_f;				\
+    _flo->bits.exp  = X##_e;				\
+    _flo->bits.sign = X##_s;				\
+  } while (0)
+  
+#define __FP_PACK_RAW_2(fs, val, X)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    _flo->bits.frac0 = X##_f0;				\
+    _flo->bits.frac1 = X##_f1;				\
+    _flo->bits.exp   = X##_e;				\
+    _flo->bits.sign  = X##_s;				\
+  } while (0)
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+
+#define __FPU_FPSCR	(current->tss.fpscr)
+
+/* We only actually write to the destination register
+ * if exceptions signalled (if any) will not trap.
+ */
+#define __FPU_ENABLED_EXC \
+({						\
+	(__FPU_FPSCR >> 3) & 0x1f;	\
+})
+
+#define __FPU_TRAP_P(bits) \
+	((__FPU_ENABLED_EXC & (bits)) != 0)
+
+#define __FP_PACK_S(val,X)			\
+({  int __exc = _FP_PACK_CANONICAL(S,1,X);	\
+    if(!__exc || !__FPU_TRAP_P(__exc))		\
+        __FP_PACK_RAW_1(S,val,X);		\
+    __exc;					\
+})
+
+#define __FP_PACK_D(val,X)			\
+	fp_pack_d(val, X##_s, X##_f1, X##_f0, X##_e, X##_c)
+
+#define __FP_PACK_DS(val,X)			\
+	fp_pack_ds(val, X##_s, X##_f1, X##_f0, X##_e, X##_c)
+
+/* Obtain the current rounding mode. */
+#define FP_ROUNDMODE			\
+({					\
+	__FPU_FPSCR & 0x3;		\
+})
+
+/* the asm fragments go here: all these are taken from glibc-2.0.5's
+ * stdlib/longlong.h
+ */
+
+#include <linux/types.h>
+#include <asm/byteorder.h>
+
+/* add_ssaaaa is used in op-2.h and should be equivalent to
+ * #define add_ssaaaa(sh,sl,ah,al,bh,bl) (sh = ah+bh+ (( sl = al+bl) < al))
+ * add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
+ * high_addend_2, low_addend_2) adds two UWtype integers, composed by
+ * HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and LOW_ADDEND_2
+ * respectively.  The result is placed in HIGH_SUM and LOW_SUM.  Overflow
+ * (i.e. carry out) is not stored anywhere, and is lost.
+ */
+#define add_ssaaaa(sh, sl, ah, al, bh, bl)				\
+  do {									\
+    if (__builtin_constant_p (bh) && (bh) == 0)				\
+      __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{aze|addze} %0,%2"		\
+	     : "=r" ((USItype)(sh)),					\
+	       "=&r" ((USItype)(sl))					\
+	     : "%r" ((USItype)(ah)),					\
+	       "%r" ((USItype)(al)),					\
+	       "rI" ((USItype)(bl)));					\
+    else if (__builtin_constant_p (bh) && (bh) ==~(USItype) 0)		\
+      __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{ame|addme} %0,%2"		\
+	     : "=r" ((USItype)(sh)),					\
+	       "=&r" ((USItype)(sl))					\
+	     : "%r" ((USItype)(ah)),					\
+	       "%r" ((USItype)(al)),					\
+	       "rI" ((USItype)(bl)));					\
+    else								\
+      __asm__ ("{a%I5|add%I5c} %1,%4,%5\n\t{ae|adde} %0,%2,%3"		\
+	     : "=r" ((USItype)(sh)),					\
+	       "=&r" ((USItype)(sl))					\
+	     : "%r" ((USItype)(ah)),					\
+	       "r" ((USItype)(bh)),					\
+	       "%r" ((USItype)(al)),					\
+	       "rI" ((USItype)(bl)));					\
+  } while (0)
+
+/* sub_ddmmss is used in op-2.h and udivmodti4.c and should be equivalent to
+ * #define sub_ddmmss(sh, sl, ah, al, bh, bl) (sh = ah-bh - ((sl = al-bl) > al))
+ * sub_ddmmss(high_difference, low_difference, high_minuend, low_minuend,
+ * high_subtrahend, low_subtrahend) subtracts two two-word UWtype integers,
+ * composed by HIGH_MINUEND_1 and LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and
+ * LOW_SUBTRAHEND_2 respectively.  The result is placed in HIGH_DIFFERENCE
+ * and LOW_DIFFERENCE.  Overflow (i.e. carry out) is not stored anywhere,
+ * and is lost.
+ */
+#define sub_ddmmss(sh, sl, ah, al, bh, bl)				\
+  do {									\
+    if (__builtin_constant_p (ah) && (ah) == 0)				\
+      __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfze|subfze} %0,%2"	\
+	       : "=r" ((USItype)(sh)),					\
+		 "=&r" ((USItype)(sl))					\
+	       : "r" ((USItype)(bh)),					\
+		 "rI" ((USItype)(al)),					\
+		 "r" ((USItype)(bl)));					\
+    else if (__builtin_constant_p (ah) && (ah) ==~(USItype) 0)		\
+      __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfme|subfme} %0,%2"	\
+	       : "=r" ((USItype)(sh)),					\
+		 "=&r" ((USItype)(sl))					\
+	       : "r" ((USItype)(bh)),					\
+		 "rI" ((USItype)(al)),					\
+		 "r" ((USItype)(bl)));					\
+    else if (__builtin_constant_p (bh) && (bh) == 0)			\
+      __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{ame|addme} %0,%2"		\
+	       : "=r" ((USItype)(sh)),					\
+		 "=&r" ((USItype)(sl))					\
+	       : "r" ((USItype)(ah)),					\
+		 "rI" ((USItype)(al)),					\
+		 "r" ((USItype)(bl)));					\
+    else if (__builtin_constant_p (bh) && (bh) ==~(USItype) 0)		\
+      __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{aze|addze} %0,%2"		\
+	       : "=r" ((USItype)(sh)),					\
+		 "=&r" ((USItype)(sl))					\
+	       : "r" ((USItype)(ah)),					\
+		 "rI" ((USItype)(al)),					\
+		 "r" ((USItype)(bl)));					\
+    else								\
+      __asm__ ("{sf%I4|subf%I4c} %1,%5,%4\n\t{sfe|subfe} %0,%3,%2"	\
+	       : "=r" ((USItype)(sh)),					\
+		 "=&r" ((USItype)(sl))					\
+	       : "r" ((USItype)(ah)),					\
+		 "r" ((USItype)(bh)),					\
+		 "rI" ((USItype)(al)),					\
+		 "r" ((USItype)(bl)));					\
+  } while (0)
+
+/* asm fragments for mul and div */	 
+
+/* umul_ppmm(high_prod, low_prod, multipler, multiplicand) multiplies two
+ * UWtype integers MULTIPLER and MULTIPLICAND, and generates a two UWtype
+ * word product in HIGH_PROD and LOW_PROD.
+ */
+#define umul_ppmm(ph, pl, m0, m1)					\
+  do {									\
+    USItype __m0 = (m0), __m1 = (m1);					\
+    __asm__ ("mulhwu %0,%1,%2"						\
+	     : "=r" ((USItype)(ph))					\
+	     : "%r" (__m0),						\
+               "r" (__m1));						\
+    (pl) = __m0 * __m1;							\
+  } while (0)
+
+/* udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
+ * denominator) divides a UDWtype, composed by the UWtype integers
+ * HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and places the quotient
+ * in QUOTIENT and the remainder in REMAINDER.  HIGH_NUMERATOR must be less
+ * than DENOMINATOR for correct operation.  If, in addition, the most
+ * significant bit of DENOMINATOR must be 1, then the pre-processor symbol
+ * UDIV_NEEDS_NORMALIZATION is defined to 1.
+ */
+#define udiv_qrnnd(q, r, n1, n0, d)					\
+  do {									\
+    UWtype __d1, __d0, __q1, __q0, __r1, __r0, __m;			\
+    __d1 = __ll_highpart (d);						\
+    __d0 = __ll_lowpart (d);						\
+									\
+    __r1 = (n1) % __d1;							\
+    __q1 = (n1) / __d1;							\
+    __m = (UWtype) __q1 * __d0;						\
+    __r1 = __r1 * __ll_B | __ll_highpart (n0);				\
+    if (__r1 < __m)							\
+      {									\
+	__q1--, __r1 += (d);						\
+	if (__r1 >= (d)) /* we didn't get carry when adding to __r1 */	\
+	  if (__r1 < __m)						\
+	    __q1--, __r1 += (d);					\
+      }									\
+    __r1 -= __m;							\
+									\
+    __r0 = __r1 % __d1;							\
+    __q0 = __r1 / __d1;							\
+    __m = (UWtype) __q0 * __d0;						\
+    __r0 = __r0 * __ll_B | __ll_lowpart (n0);				\
+    if (__r0 < __m)							\
+      {									\
+	__q0--, __r0 += (d);						\
+	if (__r0 >= (d))						\
+	  if (__r0 < __m)						\
+	    __q0--, __r0 += (d);					\
+      }									\
+    __r0 -= __m;							\
+									\
+    (q) = (UWtype) __q1 * __ll_B | __q0;				\
+    (r) = __r0;								\
+  } while (0)
+
+#define UDIV_NEEDS_NORMALIZATION 1
+
+#define abort()								\
+	return 0
+
+#ifdef __BIG_ENDIAN
+#define __BYTE_ORDER __BIG_ENDIAN
+#else
+#define __BYTE_ORDER __LITTLE_ENDIAN
+#endif
+
+/* Exception flags. */
+#define EFLAG_INVALID		(1 << (31 - 2))
+#define EFLAG_OVERFLOW		(1 << (31 - 3))
+#define EFLAG_UNDERFLOW		(1 << (31 - 4))
+#define EFLAG_DIVZERO		(1 << (31 - 5))
+#define EFLAG_INEXACT		(1 << (31 - 6))
+
+#define EFLAG_VXSNAN		(1 << (31 - 7))
+#define EFLAG_VXISI		(1 << (31 - 8))
+#define EFLAG_VXIDI		(1 << (31 - 9))
+#define EFLAG_VXZDZ		(1 << (31 - 10))
+#define EFLAG_VXIMZ		(1 << (31 - 11))
+#define EFLAG_VXVC		(1 << (31 - 12))
+#define EFLAG_VXSOFT		(1 << (31 - 21))
+#define EFLAG_VXSQRT		(1 << (31 - 22))
+#define EFLAG_VXCVI		(1 << (31 - 23))