| /* 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(_FP_WFRACBITS_S,R,X,Y,umul_ppmm) |
| #define _FP_MUL_MEAT_D(R,X,Y) _FP_MUL_MEAT_2_wide(_FP_WFRACBITS_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(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 << 1) - 1) |
| #define _FP_NANFRAC_D ((_FP_QNANBIT_D << 1) - 1), -1 |
| #define _FP_NANFRAC_Q ((_FP_QNANBIT_Q << 1) - 1), -1, -1, -1 |
| #define _FP_NANSIGN_S 0 |
| #define _FP_NANSIGN_D 0 |
| #define _FP_NANSIGN_Q 0 |
| |
| #define _FP_KEEPNANFRACP 1 |
| |
| /* Exception flags. We use the bit positions of the appropriate bits |
| in the FPSCR, which also correspond to the FE_* bits. This makes |
| everything easier ;-). */ |
| #define FP_EX_INVALID (1 << (31 - 2)) |
| #define FP_EX_INVALID_SNAN EFLAG_VXSNAN |
| #define FP_EX_INVALID_ISI EFLAG_VXISI |
| #define FP_EX_INVALID_IDI EFLAG_VXIDI |
| #define FP_EX_INVALID_ZDZ EFLAG_VXZDZ |
| #define FP_EX_INVALID_IMZ EFLAG_VXIMZ |
| #define FP_EX_OVERFLOW (1 << (31 - 3)) |
| #define FP_EX_UNDERFLOW (1 << (31 - 4)) |
| #define FP_EX_DIVZERO (1 << (31 - 5)) |
| #define FP_EX_INEXACT (1 << (31 - 6)) |
| |
| /* 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, OP) \ |
| do { \ |
| R##_s = Y##_s; \ |
| _FP_FRAC_COPY_##wc(R,Y); \ |
| R##_c = FP_CLS_NAN; \ |
| } while (0) |
| |
| |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| |
| #define __FPU_FPSCR (current->thread.fpscr.val) |
| |
| /* 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_P(S,val,X); \ |
| __exc; \ |
| }) |
| |
| #define __FP_PACK_D(val,X) \ |
| do { \ |
| _FP_PACK_CANONICAL(D, 2, X); \ |
| if (!FP_CUR_EXCEPTIONS || !__FPU_TRAP_P(FP_CUR_EXCEPTIONS)) \ |
| _FP_PACK_RAW_2_P(D, val, X); \ |
| } while (0) |
| |
| #define __FP_PACK_DS(val,X) \ |
| do { \ |
| FP_DECL_S(__X); \ |
| FP_CONV(S, D, 1, 2, __X, X); \ |
| _FP_PACK_CANONICAL(S, 1, __X); \ |
| if (!FP_CUR_EXCEPTIONS || !__FPU_TRAP_P(FP_CUR_EXCEPTIONS)) { \ |
| _FP_UNPACK_CANONICAL(S, 1, __X); \ |
| FP_CONV(D, S, 2, 1, X, __X); \ |
| _FP_PACK_CANONICAL(D, 2, X); \ |
| if (!FP_CUR_EXCEPTIONS || !__FPU_TRAP_P(FP_CUR_EXCEPTIONS)) \ |
| _FP_PACK_RAW_2_P(D, val, X); \ |
| } \ |
| } while (0) |
| |
| /* 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)) |