patch-2.1.97 linux/arch/sparc/math-emu/sfp-machine.h

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diff -u --recursive --new-file v2.1.96/linux/arch/sparc/math-emu/sfp-machine.h linux/arch/sparc/math-emu/sfp-machine.h
@@ -0,0 +1,363 @@
+/* Machine-dependent software floating-point definitions.  Sparc 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 sparc (32bit) version, written based on the
+   i386 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
+
+/* 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)
+/* FIXME: This is not implemented, but should be soon */
+#define _FP_MUL_MEAT_Q(R,X,Y)   _FP_FRAC_SET_4(R, _FP_ZEROFRAC_4)
+#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)
+/* FIXME: This is not implemented, but should be soon */
+#define _FP_DIV_MEAT_Q(R,X,Y)   _FP_FRAC_SET_4(R, _FP_ZEROFRAC_4)
+
+/* 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)
+  
+#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_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_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_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)
+
+#define __FP_UNPACK_RAW_4(fs, X, val)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    X##_f[0] = _flo->bits.frac0;			\
+    X##_f[1] = _flo->bits.frac1;			\
+    X##_f[2] = _flo->bits.frac2;			\
+    X##_f[3] = _flo->bits.frac3;			\
+    X##_e  = _flo->bits.exp;				\
+    X##_s  = _flo->bits.sign;				\
+  } while (0)
+
+#define __FP_PACK_RAW_4(fs, val, X)			\
+  do {							\
+    union _FP_UNION_##fs *_flo =			\
+    	(union _FP_UNION_##fs *)val;			\
+							\
+    _flo->bits.frac0 = X##_f[0];			\
+    _flo->bits.frac1 = X##_f[1];			\
+    _flo->bits.frac2 = X##_f[2];			\
+    _flo->bits.frac3 = X##_f[3];			\
+    _flo->bits.exp   = X##_e;				\
+    _flo->bits.sign  = X##_s;				\
+  } 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_PACK_S(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(S,1,X);		\
+    __FP_PACK_RAW_1(S,val,X);		\
+  } while (0)
+
+#define __FP_UNPACK_D(X,val)		\
+  do {					\
+    __FP_UNPACK_RAW_2(D,X,val);		\
+    _FP_UNPACK_CANONICAL(D,2,X);	\
+  } while (0)
+
+#define __FP_PACK_D(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(D,2,X);		\
+    __FP_PACK_RAW_2(D,val,X);		\
+  } while (0)
+
+#define __FP_UNPACK_Q(X,val)		\
+  do {					\
+    __FP_UNPACK_RAW_4(Q,X,val);		\
+    _FP_UNPACK_CANONICAL(Q,4,X);	\
+  } while (0)
+
+#define __FP_PACK_Q(val,X)		\
+  do {					\
+    _FP_PACK_CANONICAL(Q,4,X);		\
+    __FP_PACK_RAW_4(Q,val,X);		\
+  } while (0)
+
+/* 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) \
+  __asm__ ("addcc %r4,%5,%1
+        addx %r2,%3,%0"                                                 \
+           : "=r" ((USItype)(sh)),                                      \
+             "=&r" ((USItype)(sl))                                      \
+           : "%rJ" ((USItype)(ah)),                                     \
+             "rI" ((USItype)(bh)),                                      \
+             "%rJ" ((USItype)(al)),                                     \
+             "rI" ((USItype)(bl))                                       \
+           : "cc")
+
+
+/* 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) \
+  __asm__ ("subcc %r4,%5,%1
+        subx %r2,%3,%0"                                                 \
+           : "=r" ((USItype)(sh)),                                      \
+             "=&r" ((USItype)(sl))                                      \
+           : "rJ" ((USItype)(ah)),                                      \
+             "rI" ((USItype)(bh)),                                      \
+             "rJ" ((USItype)(al)),                                      \
+             "rI" ((USItype)(bl))                                       \
+           : "cc")
+
+
+/* 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.
+ * These look ugly because the sun4/4c don't have umul/udiv/smul/sdiv in
+ * hardware. 
+ */
+#define umul_ppmm(w1, w0, u, v) \
+  __asm__ ("! Inlined umul_ppmm
+        wr      %%g0,%2,%%y     ! SPARC has 0-3 delay insn after a wr
+        sra     %3,31,%%g2      ! Don't move this insn
+        and     %2,%%g2,%%g2    ! Don't move this insn
+        andcc   %%g0,0,%%g1     ! Don't move this insn
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,%3,%%g1
+        mulscc  %%g1,0,%%g1
+        add     %%g1,%%g2,%0
+        rd      %%y,%1"                                                 \
+           : "=r" ((USItype)(w1)),                                      \
+             "=r" ((USItype)(w0))                                       \
+           : "%rI" ((USItype)(u)),                                      \
+             "r" ((USItype)(v))                                         \
+           : "%g1", "%g2", "cc")
+
+/* 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) \
+  __asm__ ("! Inlined udiv_qrnnd
+        mov     32,%%g1
+        subcc   %1,%2,%%g0
+1:      bcs     5f
+         addxcc %0,%0,%0        ! shift n1n0 and a q-bit in lsb
+        sub     %1,%2,%1        ! this kills msb of n
+        addx    %1,%1,%1        ! so this can't give carry
+        subcc   %%g1,1,%%g1
+2:      bne     1b
+         subcc  %1,%2,%%g0
+        bcs     3f
+         addxcc %0,%0,%0        ! shift n1n0 and a q-bit in lsb
+        b       3f
+         sub    %1,%2,%1        ! this kills msb of n
+4:      sub     %1,%2,%1
+5:      addxcc  %1,%1,%1
+        bcc     2b
+         subcc  %%g1,1,%%g1
+! Got carry from n.  Subtract next step to cancel this carry.
+        bne     4b
+         addcc  %0,%0,%0        ! shift n1n0 and a 0-bit in lsb
+        sub     %1,%2,%1
+3:      xnor    %0,0,%0
+        ! End of inline udiv_qrnnd"                                     \
+           : "=&r" ((USItype) (q)),                                     \
+             "=&r" ((USItype) (r))                                      \
+           : "r" ((USItype) (d)),                                       \
+             "1" ((USItype) (n1)),                                      \
+             "0" ((USItype) (n0)) : "%g1", "cc")
+
+#define UDIV_NEEDS_NORMALIZATION 0
+
+#define abort()								\
+	return 0
+
+#ifdef __BIG_ENDIAN
+#define __BYTE_ORDER __BIG_ENDIAN
+#else
+#define __BYTE_ORDER __LITTLE_ENDIAN
+#endif
+

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