diff options
author | Jason Wright <jason@cvs.openbsd.org> | 2001-09-08 22:33:52 +0000 |
---|---|---|
committer | Jason Wright <jason@cvs.openbsd.org> | 2001-09-08 22:33:52 +0000 |
commit | a7e6a29d369556fc025b65a733ded532aa2ee8f4 (patch) | |
tree | 0e4bad64720614d5df7ad7f7a6346c4b7eaf4adb /sys/arch | |
parent | c0ab76ae3bf9a1894020b69ba9c978d75d238d2c (diff) |
Import netbsd's fpu handling (modified to be separate from sparc); this is
for paranoia's sake (don't want to break sparc32 while hacking on it).
Real work by art.
Diffstat (limited to 'sys/arch')
-rw-r--r-- | sys/arch/sparc64/conf/files.sparc64 | 20 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu.c | 565 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_add.c | 217 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_arith.h | 97 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_compare.c | 165 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_div.c | 268 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_emu.h | 196 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_explode.c | 309 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_extern.h | 100 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_implode.c | 535 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_mul.c | 227 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_sqrt.c | 398 | ||||
-rw-r--r-- | sys/arch/sparc64/fpu/fpu_subr.c | 224 |
13 files changed, 3311 insertions, 10 deletions
diff --git a/sys/arch/sparc64/conf/files.sparc64 b/sys/arch/sparc64/conf/files.sparc64 index df251184862..9f49074074b 100644 --- a/sys/arch/sparc64/conf/files.sparc64 +++ b/sys/arch/sparc64/conf/files.sparc64 @@ -1,4 +1,4 @@ -# $OpenBSD: files.sparc64,v 1.13 2001/09/06 11:01:19 art Exp $ +# $OpenBSD: files.sparc64,v 1.14 2001/09/08 22:33:51 jason Exp $ # $NetBSD: files.sparc64,v 1.50 2001/08/10 20:53:50 eeh Exp $ # maxpartitions must be first item in files.${ARCH} @@ -105,15 +105,15 @@ file dev/sun/sunms.c ms needs-flag file dev/cons.c file arch/sparc64/dev/consinit.c -file arch/sparc/fpu/fpu.c -file arch/sparc/fpu/fpu_add.c -file arch/sparc/fpu/fpu_compare.c -file arch/sparc/fpu/fpu_div.c -file arch/sparc/fpu/fpu_explode.c -file arch/sparc/fpu/fpu_implode.c -file arch/sparc/fpu/fpu_mul.c -file arch/sparc/fpu/fpu_sqrt.c -file arch/sparc/fpu/fpu_subr.c +file arch/sparc64/fpu/fpu.c +file arch/sparc64/fpu/fpu_add.c +file arch/sparc64/fpu/fpu_compare.c +file arch/sparc64/fpu/fpu_div.c +file arch/sparc64/fpu/fpu_explode.c +file arch/sparc64/fpu/fpu_implode.c +file arch/sparc64/fpu/fpu_mul.c +file arch/sparc64/fpu/fpu_sqrt.c +file arch/sparc64/fpu/fpu_subr.c # N.B.: optimizer breaks pmap.c and/or cache.c somehow -- have not # identified the exact problem yet. NOOPT_C suffices for now. diff --git a/sys/arch/sparc64/fpu/fpu.c b/sys/arch/sparc64/fpu/fpu.c new file mode 100644 index 00000000000..2f4d8137fe9 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu.c @@ -0,0 +1,565 @@ +/* $OpenBSD: fpu.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu.c,v 1.11 2000/12/06 01:47:50 mrg Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu.c 8.1 (Berkeley) 6/11/93 + */ + +#include <sys/param.h> +#include <sys/proc.h> +#include <sys/signal.h> +#include <sys/systm.h> +#include <sys/syslog.h> +#include <sys/signalvar.h> + +#include <machine/instr.h> +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_emu.h> +#include <sparc64/fpu/fpu_extern.h> + +/* + * fpu_execute returns the following error numbers (0 = no error): + */ +#define FPE 1 /* take a floating point exception */ +#define NOTFPU 2 /* not an FPU instruction */ + +/* + * Translate current exceptions into `first' exception. The + * bits go the wrong way for ffs() (0x10 is most important, etc). + * There are only 5, so do it the obvious way. + */ +#define X1(x) x +#define X2(x) x,x +#define X4(x) x,x,x,x +#define X8(x) X4(x),X4(x) +#define X16(x) X8(x),X8(x) + +static char cx_to_trapx[] = { + X1(FSR_NX), + X2(FSR_DZ), + X4(FSR_UF), + X8(FSR_OF), + X16(FSR_NV) +}; +static u_char fpu_codes[] = { + X1(FPE_FLTINEX_TRAP), + X2(FPE_FLTDIV_TRAP), + X4(FPE_FLTUND_TRAP), + X8(FPE_FLTOVF_TRAP), + X16(FPE_FLTOPERR_TRAP) +}; + +static int fpu_types[] = { + FPE_FLTRES, + FPE_FLTDIV, + FPE_FLTUND, + FPE_FLTOVF, + FPE_FLTINV, +}; + +/* + * The FPU gave us an exception. Clean up the mess. Note that the + * fp queue can only have FPops in it, never load/store FP registers + * nor FBfcc instructions. Experiments with `crashme' prove that + * unknown FPops do enter the queue, however. + */ +void +fpu_cleanup(p, fs) + register struct proc *p; +#ifndef SUN4U + register struct fpstate *fs; +#else /* SUN4U */ + register struct fpstate64 *fs; +#endif /* SUN4U */ +{ + register int i, fsr = fs->fs_fsr, error; + union instr instr; + union sigval sv; + struct fpemu fe; + + sv.sival_int = p->p_md.md_tf->tf_pc; /* XXX only approximate */ + + switch ((fsr >> FSR_FTT_SHIFT) & FSR_FTT_MASK) { + + case FSR_TT_NONE: +#if 0 + /* XXX I'm not sure how we get here, but ignoring the trap */ + /* XXX seems to work in my limited tests */ + /* XXX More research to be done =) */ + panic("fpu_cleanup 1"); /* ??? */ +#else + printf("fpu_cleanup 1\n"); +#endif + break; + + case FSR_TT_IEEE: + if ((i = fsr & FSR_CX) == 0) + panic("fpu ieee trap, but no exception"); + trapsignal(p, SIGFPE, fpu_codes[i - 1], fpu_types[i - i], sv); + break; /* XXX should return, but queue remains */ + + case FSR_TT_UNFIN: +#ifdef SUN4U + if (fs->fs_qsize == 0) { + printf("fpu_cleanup: unfinished fpop"); + /* The book sez reexecute or emulate. */ + return; + } + break; +#endif /* SUN4U */ + case FSR_TT_UNIMP: + if (fs->fs_qsize == 0) + panic("fpu_cleanup: unimplemented fpop"); + break; + + case FSR_TT_SEQ: + panic("fpu sequence error"); + /* NOTREACHED */ + + case FSR_TT_HWERR: + log(LOG_ERR, "fpu hardware error (%s[%d])\n", + p->p_comm, p->p_pid); + uprintf("%s[%d]: fpu hardware error\n", p->p_comm, p->p_pid); + trapsignal(p, SIGFPE, -1, FPE_FLTINV, sv); /* ??? */ + goto out; + + default: + printf("fsr=0x%x\n", fsr); + panic("fpu error"); + } + + /* emulate the instructions left in the queue */ + fe.fe_fpstate = fs; + for (i = 0; i < fs->fs_qsize; i++) { + instr.i_int = fs->fs_queue[i].fq_instr; + if (instr.i_any.i_op != IOP_reg || + (instr.i_op3.i_op3 != IOP3_FPop1 && + instr.i_op3.i_op3 != IOP3_FPop2)) + panic("bogus fpu queue"); + error = fpu_execute(&fe, instr); + switch (error) { + + case 0: + continue; + + case FPE: + trapsignal(p, SIGFPE, + fpu_codes[(fs->fs_fsr & FSR_CX) - 1], + fpu_types[(fs->fs_fsr & FSR_CX) - 1], sv); + break; + + case NOTFPU: + trapsignal(p, SIGILL, 0, ILL_COPROC, sv); + break; + + default: + panic("fpu_cleanup 3"); + /* NOTREACHED */ + } + /* XXX should stop here, but queue remains */ + } +out: + fs->fs_qsize = 0; +} + +#ifdef notyet +/* + * If we have no FPU at all (are there any machines like this out + * there!?) we have to emulate each instruction, and we need a pointer + * to the trapframe so that we can step over them and do FBfcc's. + * We know the `queue' is empty, though; we just want to emulate + * the instruction at tf->tf_pc. + */ +fpu_emulate(p, tf, fs) + struct proc *p; + register struct trapframe *tf; +#ifndef SUN4U + register struct fpstate *fs; +#else /* SUN4U */ + register struct fpstate64 *fs; +#endif /* SUN4U */ +{ + + do { + fetch instr from pc + decode + if (integer instr) { + /* + * We do this here, rather than earlier, to avoid + * losing even more badly than usual. + */ + if (p->p_addr->u_pcb.pcb_uw) { + write_user_windows(); + if (rwindow_save(p)) + sigexit(p, SIGILL); + } + if (loadstore) { + do_it; + pc = npc, npc += 4 + } else if (fbfcc) { + do_annul_stuff; + } else + return; + } else if (fpu instr) { + fe.fe_fsr = fs->fs_fsr &= ~FSR_CX; + error = fpu_execute(&fe, fs, instr); + switch (error) { + etc; + } + } else + return; + if (want to reschedule) + return; + } while (error == 0); +} +#endif + +/* + * Execute an FPU instruction (one that runs entirely in the FPU; not + * FBfcc or STF, for instance). On return, fe->fe_fs->fs_fsr will be + * modified to reflect the setting the hardware would have left. + * + * Note that we do not catch all illegal opcodes, so you can, for instance, + * multiply two integers this way. + */ +int +fpu_execute(fe, instr) + register struct fpemu *fe; + union instr instr; +{ + register struct fpn *fp; +#ifndef SUN4U + register int opf, rs1, rs2, rd, type, mask, fsr, cx; + register struct fpstate *fs; +#else /* SUN4U */ + register int opf, rs1, rs2, rd, type, mask, fsr, cx, i, cond; + register struct fpstate64 *fs; +#endif /* SUN4U */ + u_int space[4]; + + /* + * `Decode' and execute instruction. Start with no exceptions. + * The type of any i_opf opcode is in the bottom two bits, so we + * squish them out here. + */ + opf = instr.i_opf.i_opf; + type = opf & 3; + mask = "\0\0\1\3"[type]; + rs1 = instr.i_opf.i_rs1 & ~mask; + rs2 = instr.i_opf.i_rs2 & ~mask; + rd = instr.i_opf.i_rd & ~mask; +#ifdef notdef + if ((rs1 | rs2 | rd) & mask) + return (BADREG); +#endif + fs = fe->fe_fpstate; + fe->fe_fsr = fs->fs_fsr & ~FSR_CX; + fe->fe_cx = 0; +#ifdef SUN4U + /* + * Check to see if we're dealing with a fancy cmove and handle + * it first. + */ + if (instr.i_op3.i_op3 == IOP3_FPop2 && (opf&0xff0) != (FCMP&0xff0)) { + switch (opf >>= 2) { + case FMVFC0 >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FMVFC0\n")); + cond = (fs->fs_fsr>>FSR_FCC_SHIFT)&FSR_FCC_MASK; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVFC1 >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FMVFC1\n")); + cond = (fs->fs_fsr>>FSR_FCC1_SHIFT)&FSR_FCC_MASK; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVFC2 >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FMVFC2\n")); + cond = (fs->fs_fsr>>FSR_FCC2_SHIFT)&FSR_FCC_MASK; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVFC3 >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FMVFC3\n")); + cond = (fs->fs_fsr>>FSR_FCC3_SHIFT)&FSR_FCC_MASK; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVIC >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVIC\n")); + cond = (curproc->p_md.md_tf->tf_tstate>>TSTATE_CCR_SHIFT)&PSR_ICC; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVXC >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVXC\n")); + cond = (curproc->p_md.md_tf->tf_tstate>>(TSTATE_CCR_SHIFT+XCC_SHIFT))&PSR_ICC; + if (instr.i_fmovcc.i_cond != cond) return(0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 != 0 && (int64_t)curproc->p_md.md_tf->tf_global[rs1] != 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRLEZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRLEZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 != 0 && (int64_t)curproc->p_md.md_tf->tf_global[rs1] > 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRLZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRLZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 == 0 || (int64_t)curproc->p_md.md_tf->tf_global[rs1] >= 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRNZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRNZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 == 0 || (int64_t)curproc->p_md.md_tf->tf_global[rs1] == 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRGZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRGZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 == 0 || (int64_t)curproc->p_md.md_tf->tf_global[rs1] <= 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + case FMVRGEZ >> 2: + /* Presume we're curproc */ + DPRINTF(FPE_INSN, ("fpu_execute: FMVRGEZ\n")); + rs1 = instr.i_fmovr.i_rs1; + if (rs1 != 0 && (int64_t)curproc->p_md.md_tf->tf_global[rs1] < 0) + return (0); /* success */ + rs1 = fs->fs_regs[rs2]; + goto mov; + default: + DPRINTF(FPE_INSN, + ("fpu_execute: unknown v9 FP inst %x opf %x\n", + instr.i_int, opf)); + return (NOTFPU); + } + } +#endif /* SUN4U */ + switch (opf >>= 2) { + + default: + DPRINTF(FPE_INSN, + ("fpu_execute: unknown basic FP inst %x opf %x\n", + instr.i_int, opf)); + return (NOTFPU); + + case FMOV >> 2: /* these should all be pretty obvious */ + DPRINTF(FPE_INSN, ("fpu_execute: FMOV\n")); + rs1 = fs->fs_regs[rs2]; + goto mov; + + case FNEG >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FNEG\n")); + rs1 = fs->fs_regs[rs2] ^ (1 << 31); + goto mov; + + case FABS >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FABS\n")); + rs1 = fs->fs_regs[rs2] & ~(1 << 31); + mov: +#ifndef SUN4U + fs->fs_regs[rd] = rs1; +#else /* SUN4U */ + i = 1<<type; + fs->fs_regs[rd++] = rs1; + while (--i) + fs->fs_regs[rd++] = fs->fs_regs[++rs2]; +#endif /* SUN4U */ + fs->fs_fsr = fe->fe_fsr; + return (0); /* success */ + + case FSQRT >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FSQRT\n")); + fpu_explode(fe, &fe->fe_f1, type, rs2); + fp = fpu_sqrt(fe); + break; + + case FADD >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FADD\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fp = fpu_add(fe); + break; + + case FSUB >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FSUB\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fp = fpu_sub(fe); + break; + + case FMUL >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FMUL\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fp = fpu_mul(fe); + break; + + case FDIV >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FDIV\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fp = fpu_div(fe); + break; + + case FCMP >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FCMP\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fpu_compare(fe, 0); + goto cmpdone; + + case FCMPE >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FCMPE\n")); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + fpu_compare(fe, 1); + cmpdone: + /* + * The only possible exception here is NV; catch it + * early and get out, as there is no result register. + */ + cx = fe->fe_cx; + fsr = fe->fe_fsr | (cx << FSR_CX_SHIFT); + if (cx != 0) { + if (fsr & (FSR_NV << FSR_TEM_SHIFT)) { + fs->fs_fsr = (fsr & ~FSR_FTT) | + (FSR_TT_IEEE << FSR_FTT_SHIFT); + return (FPE); + } + fsr |= FSR_NV << FSR_AX_SHIFT; + } + fs->fs_fsr = fsr; + return (0); + + case FSMULD >> 2: + case FDMULX >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FSMULx\n")); + if (type == FTYPE_EXT) + return (NOTFPU); + fpu_explode(fe, &fe->fe_f1, type, rs1); + fpu_explode(fe, &fe->fe_f2, type, rs2); + type++; /* single to double, or double to quad */ + fp = fpu_mul(fe); + break; + +#ifdef SUN4U + case FXTOS >> 2: + case FXTOD >> 2: + case FXTOQ >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FXTOx\n")); + type = FTYPE_LNG; + fpu_explode(fe, fp = &fe->fe_f1, type, rs2); + type = opf & 3; /* sneaky; depends on instruction encoding */ + break; + + case FTOX >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FTOx\n")); + fpu_explode(fe, fp = &fe->fe_f1, type, rs2); + type = FTYPE_LNG; + break; +#endif /* SUN4U */ + + case FTOS >> 2: + case FTOD >> 2: + case FTOQ >> 2: + case FTOI >> 2: + DPRINTF(FPE_INSN, ("fpu_execute: FTOx\n")); + fpu_explode(fe, fp = &fe->fe_f1, type, rs2); + type = opf & 3; /* sneaky; depends on instruction encoding */ + break; + } + + /* + * ALU operation is complete. Collapse the result and then check + * for exceptions. If we got any, and they are enabled, do not + * alter the destination register, just stop with an exception. + * Otherwise set new current exceptions and accrue. + */ + fpu_implode(fe, fp, type, space); + cx = fe->fe_cx; + fsr = fe->fe_fsr; + if (cx != 0) { + mask = (fsr >> FSR_TEM_SHIFT) & FSR_TEM_MASK; + if (cx & mask) { + /* not accrued??? */ + fs->fs_fsr = (fsr & ~FSR_FTT) | + (FSR_TT_IEEE << FSR_FTT_SHIFT) | + (cx_to_trapx[(cx & mask) - 1] << FSR_CX_SHIFT); + return (FPE); + } + fsr |= (cx << FSR_CX_SHIFT) | (cx << FSR_AX_SHIFT); + } + fs->fs_fsr = fsr; + fs->fs_regs[rd] = space[0]; + if (type >= FTYPE_DBL || type == FTYPE_LNG) { + fs->fs_regs[rd + 1] = space[1]; + if (type > FTYPE_DBL) { + fs->fs_regs[rd + 2] = space[2]; + fs->fs_regs[rd + 3] = space[3]; + } + } + return (0); /* success */ +} diff --git a/sys/arch/sparc64/fpu/fpu_add.c b/sys/arch/sparc64/fpu/fpu_add.c new file mode 100644 index 00000000000..3bbd5db4828 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_add.c @@ -0,0 +1,217 @@ +/* $OpenBSD: fpu_add.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_add.c,v 1.3 1996/03/14 19:41:52 christos Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_add.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * Perform an FPU add (return x + y). + * + * To subtract, negate y and call add. + */ + +#include <sys/types.h> +#ifdef DIAGNOSTIC +#include <sys/systm.h> +#endif + +#include <machine/reg.h> +#include <machine/instr.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> +#include <sparc64/fpu/fpu_extern.h> + +struct fpn * +fpu_add(fe) + register struct fpemu *fe; +{ + register struct fpn *x = &fe->fe_f1, *y = &fe->fe_f2, *r; + register u_int r0, r1, r2, r3; + register int rd; + + /* + * Put the `heavier' operand on the right (see fpu_emu.h). + * Then we will have one of the following cases, taken in the + * following order: + * + * - y = NaN. Implied: if only one is a signalling NaN, y is. + * The result is y. + * - y = Inf. Implied: x != NaN (is 0, number, or Inf: the NaN + * case was taken care of earlier). + * If x = -y, the result is NaN. Otherwise the result + * is y (an Inf of whichever sign). + * - y is 0. Implied: x = 0. + * If x and y differ in sign (one positive, one negative), + * the result is +0 except when rounding to -Inf. If same: + * +0 + +0 = +0; -0 + -0 = -0. + * - x is 0. Implied: y != 0. + * Result is y. + * - other. Implied: both x and y are numbers. + * Do addition a la Hennessey & Patterson. + */ + ORDER(x, y); + if (ISNAN(y)) + return (y); + if (ISINF(y)) { + if (ISINF(x) && x->fp_sign != y->fp_sign) + return (fpu_newnan(fe)); + return (y); + } + rd = ((fe->fe_fsr >> FSR_RD_SHIFT) & FSR_RD_MASK); + if (ISZERO(y)) { + if (rd != FSR_RD_RM) /* only -0 + -0 gives -0 */ + y->fp_sign &= x->fp_sign; + else /* any -0 operand gives -0 */ + y->fp_sign |= x->fp_sign; + return (y); + } + if (ISZERO(x)) + return (y); + /* + * We really have two numbers to add, although their signs may + * differ. Make the exponents match, by shifting the smaller + * number right (e.g., 1.011 => 0.1011) and increasing its + * exponent (2^3 => 2^4). Note that we do not alter the exponents + * of x and y here. + */ + r = &fe->fe_f3; + r->fp_class = FPC_NUM; + if (x->fp_exp == y->fp_exp) { + r->fp_exp = x->fp_exp; + r->fp_sticky = 0; + } else { + if (x->fp_exp < y->fp_exp) { + /* + * Try to avoid subtract case iii (see below). + * This also guarantees that x->fp_sticky = 0. + */ + SWAP(x, y); + } + /* now x->fp_exp > y->fp_exp */ + r->fp_exp = x->fp_exp; + r->fp_sticky = fpu_shr(y, x->fp_exp - y->fp_exp); + } + r->fp_sign = x->fp_sign; + if (x->fp_sign == y->fp_sign) { + FPU_DECL_CARRY + + /* + * The signs match, so we simply add the numbers. The result + * may be `supernormal' (as big as 1.111...1 + 1.111...1, or + * 11.111...0). If so, a single bit shift-right will fix it + * (but remember to adjust the exponent). + */ + /* r->fp_mant = x->fp_mant + y->fp_mant */ + FPU_ADDS(r->fp_mant[3], x->fp_mant[3], y->fp_mant[3]); + FPU_ADDCS(r->fp_mant[2], x->fp_mant[2], y->fp_mant[2]); + FPU_ADDCS(r->fp_mant[1], x->fp_mant[1], y->fp_mant[1]); + FPU_ADDC(r0, x->fp_mant[0], y->fp_mant[0]); + if ((r->fp_mant[0] = r0) >= FP_2) { + (void) fpu_shr(r, 1); + r->fp_exp++; + } + } else { + FPU_DECL_CARRY + + /* + * The signs differ, so things are rather more difficult. + * H&P would have us negate the negative operand and add; + * this is the same as subtracting the negative operand. + * This is quite a headache. Instead, we will subtract + * y from x, regardless of whether y itself is the negative + * operand. When this is done one of three conditions will + * hold, depending on the magnitudes of x and y: + * case i) |x| > |y|. The result is just x - y, + * with x's sign, but it may need to be normalized. + * case ii) |x| = |y|. The result is 0 (maybe -0) + * so must be fixed up. + * case iii) |x| < |y|. We goofed; the result should + * be (y - x), with the same sign as y. + * We could compare |x| and |y| here and avoid case iii, + * but that would take just as much work as the subtract. + * We can tell case iii has occurred by an overflow. + * + * N.B.: since x->fp_exp >= y->fp_exp, x->fp_sticky = 0. + */ + /* r->fp_mant = x->fp_mant - y->fp_mant */ + FPU_SET_CARRY(y->fp_sticky); + FPU_SUBCS(r3, x->fp_mant[3], y->fp_mant[3]); + FPU_SUBCS(r2, x->fp_mant[2], y->fp_mant[2]); + FPU_SUBCS(r1, x->fp_mant[1], y->fp_mant[1]); + FPU_SUBC(r0, x->fp_mant[0], y->fp_mant[0]); + if (r0 < FP_2) { + /* cases i and ii */ + if ((r0 | r1 | r2 | r3) == 0) { + /* case ii */ + r->fp_class = FPC_ZERO; + r->fp_sign = rd == FSR_RD_RM; + return (r); + } + } else { + /* + * Oops, case iii. This can only occur when the + * exponents were equal, in which case neither + * x nor y have sticky bits set. Flip the sign + * (to y's sign) and negate the result to get y - x. + */ +#ifdef DIAGNOSTIC + if (x->fp_exp != y->fp_exp || r->fp_sticky) + panic("fpu_add"); +#endif + r->fp_sign = y->fp_sign; + FPU_SUBS(r3, 0, r3); + FPU_SUBCS(r2, 0, r2); + FPU_SUBCS(r1, 0, r1); + FPU_SUBC(r0, 0, r0); + } + r->fp_mant[3] = r3; + r->fp_mant[2] = r2; + r->fp_mant[1] = r1; + r->fp_mant[0] = r0; + if (r0 < FP_1) + fpu_norm(r); + } + return (r); +} diff --git a/sys/arch/sparc64/fpu/fpu_arith.h b/sys/arch/sparc64/fpu/fpu_arith.h new file mode 100644 index 00000000000..f15960c0f38 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_arith.h @@ -0,0 +1,97 @@ +/* $OpenBSD: fpu_arith.h,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_arith.h,v 1.2 1994/11/20 20:52:35 deraadt Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_arith.h 8.1 (Berkeley) 6/11/93 + */ + +/* + * Extended-precision arithmetic. + * + * We hold the notion of a `carry register', which may or may not be a + * machine carry bit or register. On the SPARC, it is just the machine's + * carry bit. + * + * In the worst case, you can compute the carry from x+y as + * (unsigned)(x + y) < (unsigned)x + * and from x+y+c as + * ((unsigned)(x + y + c) <= (unsigned)x && (y|c) != 0) + * for example. + */ + +/* set up for extended-precision arithemtic */ +#define FPU_DECL_CARRY + +/* + * We have three kinds of add: + * add with carry: r = x + y + c + * add (ignoring current carry) and set carry: c'r = x + y + 0 + * add with carry and set carry: c'r = x + y + c + * The macros use `C' for `use carry' and `S' for `set carry'. + * Note that the state of the carry is undefined after ADDC and SUBC, + * so if all you have for these is `add with carry and set carry', + * that is OK. + * + * The same goes for subtract, except that we compute x - y - c. + * + * Finally, we have a way to get the carry into a `regular' variable, + * or set it from a value. SET_CARRY turns 0 into no-carry, nonzero + * into carry; GET_CARRY sets its argument to 0 or 1. + */ +#define FPU_ADDC(r, x, y) \ + asm volatile("addx %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) +#define FPU_ADDS(r, x, y) \ + asm volatile("addcc %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) +#define FPU_ADDCS(r, x, y) \ + asm volatile("addxcc %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) +#define FPU_SUBC(r, x, y) \ + asm volatile("subx %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) +#define FPU_SUBS(r, x, y) \ + asm volatile("subcc %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) +#define FPU_SUBCS(r, x, y) \ + asm volatile("subxcc %1,%2,%0" : "=r"(r) : "r"(x), "r"(y)) + +#define FPU_GET_CARRY(r) asm volatile("addx %%g0,%%g0,%0" : "=r"(r)) +#define FPU_SET_CARRY(v) asm volatile("addcc %0,-1,%%g0" : : "r"(v)) + +#define FPU_SHL1_BY_ADD /* shift left 1 faster by ADDC than (a<<1)|(b>>31) */ diff --git a/sys/arch/sparc64/fpu/fpu_compare.c b/sys/arch/sparc64/fpu/fpu_compare.c new file mode 100644 index 00000000000..2b2e462d569 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_compare.c @@ -0,0 +1,165 @@ +/* $OpenBSD: fpu_compare.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_compare.c,v 1.2 1994/11/20 20:52:37 deraadt Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_compare.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * CMP and CMPE instructions. + * + * These rely on the fact that our internal wide format is achieved by + * adding zero bits to the end of narrower mantissas. + */ + +#include <sys/types.h> + +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> + +/* + * Perform a compare instruction (with or without unordered exception). + * This updates the fcc field in the fsr. + * + * If either operand is NaN, the result is unordered. For cmpe, this + * causes an NV exception. Everything else is ordered: + * |Inf| > |numbers| > |0|. + * We already arranged for fp_class(Inf) > fp_class(numbers) > fp_class(0), + * so we get this directly. Note, however, that two zeros compare equal + * regardless of sign, while everything else depends on sign. + * + * Incidentally, two Infs of the same sign compare equal (per the 80387 + * manual---it would be nice if the SPARC documentation were more + * complete). + */ +void +fpu_compare(struct fpemu *fe, int cmpe) +{ + register struct fpn *a, *b; + register int cc, r3, r2, r1, r0; + FPU_DECL_CARRY + + a = &fe->fe_f1; + b = &fe->fe_f2; + + if (ISNAN(a) || ISNAN(b)) { + /* + * In any case, we already got an exception for signalling + * NaNs; here we may replace that one with an identical + * exception, but so what?. + */ + if (cmpe) + fe->fe_cx = FSR_NV; + cc = FSR_CC_UO; + goto done; + } + + /* + * Must handle both-zero early to avoid sign goofs. Otherwise, + * at most one is 0, and if the signs differ we are done. + */ + if (ISZERO(a) && ISZERO(b)) { + cc = FSR_CC_EQ; + goto done; + } + if (a->fp_sign) { /* a < 0 (or -0) */ + if (!b->fp_sign) { /* b >= 0 (or if a = -0, b > 0) */ + cc = FSR_CC_LT; + goto done; + } + } else { /* a > 0 (or +0) */ + if (b->fp_sign) { /* b <= -0 (or if a = +0, b < 0) */ + cc = FSR_CC_GT; + goto done; + } + } + + /* + * Now the signs are the same (but may both be negative). All + * we have left are these cases: + * + * |a| < |b| [classes or values differ] + * |a| > |b| [classes or values differ] + * |a| == |b| [classes and values identical] + * + * We define `diff' here to expand these as: + * + * |a| < |b|, a,b >= 0: a < b => FSR_CC_LT + * |a| < |b|, a,b < 0: a > b => FSR_CC_GT + * |a| > |b|, a,b >= 0: a > b => FSR_CC_GT + * |a| > |b|, a,b < 0: a < b => FSR_CC_LT + */ +#define opposite_cc(cc) ((cc) == FSR_CC_LT ? FSR_CC_GT : FSR_CC_LT) +#define diff(magnitude) (a->fp_sign ? opposite_cc(magnitude) : (magnitude)) + if (a->fp_class < b->fp_class) { /* |a| < |b| */ + cc = diff(FSR_CC_LT); + goto done; + } + if (a->fp_class > b->fp_class) { /* |a| > |b| */ + cc = diff(FSR_CC_GT); + goto done; + } + /* now none can be 0: only Inf and numbers remain */ + if (ISINF(a)) { /* |Inf| = |Inf| */ + cc = FSR_CC_EQ; + goto done; + } + /* + * Only numbers remain. To compare two numbers in magnitude, we + * simply subtract their mantissas. + */ + FPU_SUBS(r3, a->fp_mant[0], b->fp_mant[0]); + FPU_SUBCS(r2, a->fp_mant[1], b->fp_mant[1]); + FPU_SUBCS(r1, a->fp_mant[2], b->fp_mant[2]); + FPU_SUBC(r0, a->fp_mant[3], b->fp_mant[3]); + if (r0 < 0) /* underflow: |a| < |b| */ + cc = diff(FSR_CC_LT); + else if ((r0 | r1 | r2 | r3) != 0) /* |a| > |b| */ + cc = diff(FSR_CC_GT); + else + cc = FSR_CC_EQ; /* |a| == |b| */ +done: + fe->fe_fsr = (fe->fe_fsr & ~FSR_FCC) | (cc << FSR_FCC_SHIFT); +} diff --git a/sys/arch/sparc64/fpu/fpu_div.c b/sys/arch/sparc64/fpu/fpu_div.c new file mode 100644 index 00000000000..a7a622ffad3 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_div.c @@ -0,0 +1,268 @@ +/* $OpenBSD: fpu_div.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_div.c,v 1.2 1994/11/20 20:52:38 deraadt Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_div.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * Perform an FPU divide (return x / y). + */ + +#include <sys/types.h> + +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> + +/* + * Division of normal numbers is done as follows: + * + * x and y are floating point numbers, i.e., in the form 1.bbbb * 2^e. + * If X and Y are the mantissas (1.bbbb's), the quotient is then: + * + * q = (X / Y) * 2^((x exponent) - (y exponent)) + * + * Since X and Y are both in [1.0,2.0), the quotient's mantissa (X / Y) + * will be in [0.5,2.0). Moreover, it will be less than 1.0 if and only + * if X < Y. In that case, it will have to be shifted left one bit to + * become a normal number, and the exponent decremented. Thus, the + * desired exponent is: + * + * left_shift = x->fp_mant < y->fp_mant; + * result_exp = x->fp_exp - y->fp_exp - left_shift; + * + * The quotient mantissa X/Y can then be computed one bit at a time + * using the following algorithm: + * + * Q = 0; -- Initial quotient. + * R = X; -- Initial remainder, + * if (left_shift) -- but fixed up in advance. + * R *= 2; + * for (bit = FP_NMANT; --bit >= 0; R *= 2) { + * if (R >= Y) { + * Q |= 1 << bit; + * R -= Y; + * } + * } + * + * The subtraction R -= Y always removes the uppermost bit from R (and + * can sometimes remove additional lower-order 1 bits); this proof is + * left to the reader. + * + * This loop correctly calculates the guard and round bits since they are + * included in the expanded internal representation. The sticky bit + * is to be set if and only if any other bits beyond guard and round + * would be set. From the above it is obvious that this is true if and + * only if the remainder R is nonzero when the loop terminates. + * + * Examining the loop above, we can see that the quotient Q is built + * one bit at a time ``from the top down''. This means that we can + * dispense with the multi-word arithmetic and just build it one word + * at a time, writing each result word when it is done. + * + * Furthermore, since X and Y are both in [1.0,2.0), we know that, + * initially, R >= Y. (Recall that, if X < Y, R is set to X * 2 and + * is therefore at in [2.0,4.0).) Thus Q is sure to have bit FP_NMANT-1 + * set, and R can be set initially to either X - Y (when X >= Y) or + * 2X - Y (when X < Y). In addition, comparing R and Y is difficult, + * so we will simply calculate R - Y and see if that underflows. + * This leads to the following revised version of the algorithm: + * + * R = X; + * bit = FP_1; + * D = R - Y; + * if (D >= 0) { + * result_exp = x->fp_exp - y->fp_exp; + * R = D; + * q = bit; + * bit >>= 1; + * } else { + * result_exp = x->fp_exp - y->fp_exp - 1; + * q = 0; + * } + * R <<= 1; + * do { + * D = R - Y; + * if (D >= 0) { + * q |= bit; + * R = D; + * } + * R <<= 1; + * } while ((bit >>= 1) != 0); + * Q[0] = q; + * for (i = 1; i < 4; i++) { + * q = 0, bit = 1 << 31; + * do { + * D = R - Y; + * if (D >= 0) { + * q |= bit; + * R = D; + * } + * R <<= 1; + * } while ((bit >>= 1) != 0); + * Q[i] = q; + * } + * + * This can be refined just a bit further by moving the `R <<= 1' + * calculations to the front of the do-loops and eliding the first one. + * The process can be terminated immediately whenever R becomes 0, but + * this is relatively rare, and we do not bother. + */ + +struct fpn * +fpu_div(fe) + register struct fpemu *fe; +{ + register struct fpn *x = &fe->fe_f1, *y = &fe->fe_f2; + register u_int q, bit; + register u_int r0, r1, r2, r3, d0, d1, d2, d3, y0, y1, y2, y3; + FPU_DECL_CARRY + + /* + * Since divide is not commutative, we cannot just use ORDER. + * Check either operand for NaN first; if there is at least one, + * order the signalling one (if only one) onto the right, then + * return it. Otherwise we have the following cases: + * + * Inf / Inf = NaN, plus NV exception + * Inf / num = Inf [i.e., return x] + * Inf / 0 = Inf [i.e., return x] + * 0 / Inf = 0 [i.e., return x] + * 0 / num = 0 [i.e., return x] + * 0 / 0 = NaN, plus NV exception + * num / Inf = 0 + * num / num = num (do the divide) + * num / 0 = Inf, plus DZ exception + */ + if (ISNAN(x) || ISNAN(y)) { + ORDER(x, y); + return (y); + } + if (ISINF(x) || ISZERO(x)) { + if (x->fp_class == y->fp_class) + return (fpu_newnan(fe)); + return (x); + } + + /* all results at this point use XOR of operand signs */ + x->fp_sign ^= y->fp_sign; + if (ISINF(y)) { + x->fp_class = FPC_ZERO; + return (x); + } + if (ISZERO(y)) { + fe->fe_cx = FSR_DZ; + x->fp_class = FPC_INF; + return (x); + } + + /* + * Macros for the divide. See comments at top for algorithm. + * Note that we expand R, D, and Y here. + */ + +#define SUBTRACT /* D = R - Y */ \ + FPU_SUBS(d3, r3, y3); FPU_SUBCS(d2, r2, y2); \ + FPU_SUBCS(d1, r1, y1); FPU_SUBC(d0, r0, y0) + +#define NONNEGATIVE /* D >= 0 */ \ + ((int)d0 >= 0) + +#ifdef FPU_SHL1_BY_ADD +#define SHL1 /* R <<= 1 */ \ + FPU_ADDS(r3, r3, r3); FPU_ADDCS(r2, r2, r2); \ + FPU_ADDCS(r1, r1, r1); FPU_ADDC(r0, r0, r0) +#else +#define SHL1 \ + r0 = (r0 << 1) | (r1 >> 31), r1 = (r1 << 1) | (r2 >> 31), \ + r2 = (r2 << 1) | (r3 >> 31), r3 <<= 1 +#endif + +#define LOOP /* do ... while (bit >>= 1) */ \ + do { \ + SHL1; \ + SUBTRACT; \ + if (NONNEGATIVE) { \ + q |= bit; \ + r0 = d0, r1 = d1, r2 = d2, r3 = d3; \ + } \ + } while ((bit >>= 1) != 0) + +#define WORD(r, i) /* calculate r->fp_mant[i] */ \ + q = 0; \ + bit = 1 << 31; \ + LOOP; \ + (x)->fp_mant[i] = q + + /* Setup. Note that we put our result in x. */ + r0 = x->fp_mant[0]; + r1 = x->fp_mant[1]; + r2 = x->fp_mant[2]; + r3 = x->fp_mant[3]; + y0 = y->fp_mant[0]; + y1 = y->fp_mant[1]; + y2 = y->fp_mant[2]; + y3 = y->fp_mant[3]; + + bit = FP_1; + SUBTRACT; + if (NONNEGATIVE) { + x->fp_exp -= y->fp_exp; + r0 = d0, r1 = d1, r2 = d2, r3 = d3; + q = bit; + bit >>= 1; + } else { + x->fp_exp -= y->fp_exp + 1; + q = 0; + } + LOOP; + x->fp_mant[0] = q; + WORD(x, 1); + WORD(x, 2); + WORD(x, 3); + x->fp_sticky = r0 | r1 | r2 | r3; + + return (x); +} diff --git a/sys/arch/sparc64/fpu/fpu_emu.h b/sys/arch/sparc64/fpu/fpu_emu.h new file mode 100644 index 00000000000..90c9f3babe5 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_emu.h @@ -0,0 +1,196 @@ +/* $OpenBSD: fpu_emu.h,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_emu.h,v 1.4 2000/08/03 18:32:07 eeh Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_emu.h 8.1 (Berkeley) 6/11/93 + */ + +/* + * Floating point emulator (tailored for SPARC, but structurally + * machine-independent). + * + * Floating point numbers are carried around internally in an `expanded' + * or `unpacked' form consisting of: + * - sign + * - unbiased exponent + * - mantissa (`1.' + 112-bit fraction + guard + round) + * - sticky bit + * Any implied `1' bit is inserted, giving a 113-bit mantissa that is + * always nonzero. Additional low-order `guard' and `round' bits are + * scrunched in, making the entire mantissa 115 bits long. This is divided + * into four 32-bit words, with `spare' bits left over in the upper part + * of the top word (the high bits of fp_mant[0]). An internal `exploded' + * number is thus kept within the half-open interval [1.0,2.0) (but see + * the `number classes' below). This holds even for denormalized numbers: + * when we explode an external denorm, we normalize it, introducing low-order + * zero bits, so that the rest of the code always sees normalized values. + * + * Note that a number of our algorithms use the `spare' bits at the top. + * The most demanding algorithm---the one for sqrt---depends on two such + * bits, so that it can represent values up to (but not including) 8.0, + * and then it needs a carry on top of that, so that we need three `spares'. + * + * The sticky-word is 32 bits so that we can use `OR' operators to goosh + * whole words from the mantissa into it. + * + * All operations are done in this internal extended precision. According + * to Hennesey & Patterson, Appendix A, rounding can be repeated---that is, + * it is OK to do a+b in extended precision and then round the result to + * single precision---provided single, double, and extended precisions are + * `far enough apart' (they always are), but we will try to avoid any such + * extra work where possible. + */ +struct fpn { + int fp_class; /* see below */ + int fp_sign; /* 0 => positive, 1 => negative */ + int fp_exp; /* exponent (unbiased) */ + int fp_sticky; /* nonzero bits lost at right end */ + u_int fp_mant[4]; /* 115-bit mantissa */ +}; + +#define FP_NMANT 115 /* total bits in mantissa (incl g,r) */ +#define FP_NG 2 /* number of low-order guard bits */ +#define FP_LG ((FP_NMANT - 1) & 31) /* log2(1.0) for fp_mant[0] */ +#define FP_LG2 ((FP_NMANT - 1) & 63) /* log2(1.0) for fp_mant[0] and fp_mant[1] */ +#define FP_QUIETBIT (1 << (FP_LG - 1)) /* Quiet bit in NaNs (0.5) */ +#define FP_1 (1 << FP_LG) /* 1.0 in fp_mant[0] */ +#define FP_2 (1 << (FP_LG + 1)) /* 2.0 in fp_mant[0] */ + +/* + * Number classes. Since zero, Inf, and NaN cannot be represented using + * the above layout, we distinguish these from other numbers via a class. + * In addition, to make computation easier and to follow Appendix N of + * the SPARC Version 8 standard, we give each kind of NaN a separate class. + */ +#define FPC_SNAN -2 /* signalling NaN (sign irrelevant) */ +#define FPC_QNAN -1 /* quiet NaN (sign irrelevant) */ +#define FPC_ZERO 0 /* zero (sign matters) */ +#define FPC_NUM 1 /* number (sign matters) */ +#define FPC_INF 2 /* infinity (sign matters) */ + +#define ISNAN(fp) ((fp)->fp_class < 0) +#define ISZERO(fp) ((fp)->fp_class == 0) +#define ISINF(fp) ((fp)->fp_class == FPC_INF) + +/* + * ORDER(x,y) `sorts' a pair of `fpn *'s so that the right operand (y) points + * to the `more significant' operand for our purposes. Appendix N says that + * the result of a computation involving two numbers are: + * + * If both are SNaN: operand 2, converted to Quiet + * If only one is SNaN: the SNaN operand, converted to Quiet + * If both are QNaN: operand 2 + * If only one is QNaN: the QNaN operand + * + * In addition, in operations with an Inf operand, the result is usually + * Inf. The class numbers are carefully arranged so that if + * (unsigned)class(op1) > (unsigned)class(op2) + * then op1 is the one we want; otherwise op2 is the one we want. + */ +#define ORDER(x, y) { \ + if ((u_int)(x)->fp_class > (u_int)(y)->fp_class) \ + SWAP(x, y); \ +} +#define SWAP(x, y) { \ + register struct fpn *swap; \ + swap = (x), (x) = (y), (y) = swap; \ +} + +/* + * Emulator state. + */ +struct fpemu { +#ifndef SUN4U + struct fpstate *fe_fpstate; /* registers, etc */ +#else /* SUN4U */ + struct fpstate64 *fe_fpstate; /* registers, etc */ +#endif /* SUN4U */ + int fe_fsr; /* fsr copy (modified during op) */ + int fe_cx; /* exceptions */ + struct fpn fe_f1; /* operand 1 */ + struct fpn fe_f2; /* operand 2, if required */ + struct fpn fe_f3; /* available storage for result */ +}; + +/* + * Arithmetic functions. + * Each of these may modify its inputs (f1,f2) and/or the temporary. + * Each returns a pointer to the result and/or sets exceptions. + */ +struct fpn *fpu_add(struct fpemu *); +#define fpu_sub(fe) ((fe)->fe_f2.fp_sign ^= 1, fpu_add(fe)) +struct fpn *fpu_mul(struct fpemu *); +struct fpn *fpu_div(struct fpemu *); +struct fpn *fpu_sqrt(struct fpemu *); + +/* + * Other functions. + */ + +/* Perform a compare instruction (with or without unordered exception). */ +void fpu_compare(struct fpemu *, int); + +/* Build a new Quiet NaN (sign=0, frac=all 1's). */ +struct fpn *fpu_newnan(struct fpemu *); + +/* + * Shift a number right some number of bits, taking care of round/sticky. + * Note that the result is probably not a well-formed number (it will lack + * the normal 1-bit mant[0]&FP_1). + */ +int fpu_shr(struct fpn *, int); + +void fpu_explode(struct fpemu *, struct fpn *, int, int); +void fpu_implode(struct fpemu *, struct fpn *, int, u_int *); + +#ifdef DEBUG +#define FPE_INSN 0x1 +#define FPE_REG 0x2 +extern int fpe_debug; +void fpu_dumpfpn(struct fpn *); +#define DPRINTF(x, y) if (fpe_debug & (x)) printf y +#define DUMPFPN(x, f) if (fpe_debug & (x)) fpu_dumpfpn((f)) +#else +#define DPRINTF(x, y) +#define DUMPFPN(x, f) +#endif diff --git a/sys/arch/sparc64/fpu/fpu_explode.c b/sys/arch/sparc64/fpu/fpu_explode.c new file mode 100644 index 00000000000..2cc92a1fbef --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_explode.c @@ -0,0 +1,309 @@ +/* $OpenBSD: fpu_explode.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_explode.c,v 1.5 2000/08/03 18:32:08 eeh Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_explode.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * FPU subroutines: `explode' the machine's `packed binary' format numbers + * into our internal format. + */ + +#include <sys/types.h> +#include <sys/systm.h> + +#include <machine/ieee.h> +#include <machine/instr.h> +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> +#include <sparc64/fpu/fpu_extern.h> + +/* + * N.B.: in all of the following, we assume the FP format is + * + * --------------------------- + * | s | exponent | fraction | + * --------------------------- + * + * (which represents -1**s * 1.fraction * 2**exponent), so that the + * sign bit is way at the top (bit 31), the exponent is next, and + * then the remaining bits mark the fraction. A zero exponent means + * zero or denormalized (0.fraction rather than 1.fraction), and the + * maximum possible exponent, 2bias+1, signals inf (fraction==0) or NaN. + * + * Since the sign bit is always the topmost bit---this holds even for + * integers---we set that outside all the *tof functions. Each function + * returns the class code for the new number (but note that we use + * FPC_QNAN for all NaNs; fpu_explode will fix this if appropriate). + */ + +/* + * int -> fpn. + */ +int +fpu_itof(fp, i) + register struct fpn *fp; + register u_int i; +{ + + if (i == 0) + return (FPC_ZERO); + /* + * The value FP_1 represents 2^FP_LG, so set the exponent + * there and let normalization fix it up. Convert negative + * numbers to sign-and-magnitude. Note that this relies on + * fpu_norm()'s handling of `supernormals'; see fpu_subr.c. + */ + fp->fp_exp = FP_LG; + fp->fp_mant[0] = (int)i < 0 ? -i : i; + fp->fp_mant[1] = 0; + fp->fp_mant[2] = 0; + fp->fp_mant[3] = 0; + fpu_norm(fp); + return (FPC_NUM); +} + +#ifdef SUN4U +/* + * 64-bit int -> fpn. + */ +int +fpu_xtof(fp, i) + register struct fpn *fp; + register u_int64_t i; +{ + + if (i == 0) + return (FPC_ZERO); + /* + * The value FP_1 represents 2^FP_LG, so set the exponent + * there and let normalization fix it up. Convert negative + * numbers to sign-and-magnitude. Note that this relies on + * fpu_norm()'s handling of `supernormals'; see fpu_subr.c. + */ + fp->fp_exp = FP_LG2; + *((int64_t*)fp->fp_mant) = (int64_t)i < 0 ? -i : i; + fp->fp_mant[2] = 0; + fp->fp_mant[3] = 0; + fpu_norm(fp); + return (FPC_NUM); +} +#endif /* SUN4U */ + +#define mask(nbits) ((1L << (nbits)) - 1) + +/* + * All external floating formats convert to internal in the same manner, + * as defined here. Note that only normals get an implied 1.0 inserted. + */ +#define FP_TOF(exp, expbias, allfrac, f0, f1, f2, f3) \ + if (exp == 0) { \ + if (allfrac == 0) \ + return (FPC_ZERO); \ + fp->fp_exp = 1 - expbias; \ + fp->fp_mant[0] = f0; \ + fp->fp_mant[1] = f1; \ + fp->fp_mant[2] = f2; \ + fp->fp_mant[3] = f3; \ + fpu_norm(fp); \ + return (FPC_NUM); \ + } \ + if (exp == (2 * expbias + 1)) { \ + if (allfrac == 0) \ + return (FPC_INF); \ + fp->fp_mant[0] = f0; \ + fp->fp_mant[1] = f1; \ + fp->fp_mant[2] = f2; \ + fp->fp_mant[3] = f3; \ + return (FPC_QNAN); \ + } \ + fp->fp_exp = exp - expbias; \ + fp->fp_mant[0] = FP_1 | f0; \ + fp->fp_mant[1] = f1; \ + fp->fp_mant[2] = f2; \ + fp->fp_mant[3] = f3; \ + return (FPC_NUM) + +/* + * 32-bit single precision -> fpn. + * We assume a single occupies at most (64-FP_LG) bits in the internal + * format: i.e., needs at most fp_mant[0] and fp_mant[1]. + */ +int +fpu_stof(fp, i) + register struct fpn *fp; + register u_int i; +{ + register int exp; + register u_int frac, f0, f1; +#define SNG_SHIFT (SNG_FRACBITS - FP_LG) + + exp = (i >> (32 - 1 - SNG_EXPBITS)) & mask(SNG_EXPBITS); + frac = i & mask(SNG_FRACBITS); + f0 = frac >> SNG_SHIFT; + f1 = frac << (32 - SNG_SHIFT); + FP_TOF(exp, SNG_EXP_BIAS, frac, f0, f1, 0, 0); +} + +/* + * 64-bit double -> fpn. + * We assume this uses at most (96-FP_LG) bits. + */ +int +fpu_dtof(fp, i, j) + register struct fpn *fp; + register u_int i, j; +{ + register int exp; + register u_int frac, f0, f1, f2; +#define DBL_SHIFT (DBL_FRACBITS - 32 - FP_LG) + + exp = (i >> (32 - 1 - DBL_EXPBITS)) & mask(DBL_EXPBITS); + frac = i & mask(DBL_FRACBITS - 32); + f0 = frac >> DBL_SHIFT; + f1 = (frac << (32 - DBL_SHIFT)) | (j >> DBL_SHIFT); + f2 = j << (32 - DBL_SHIFT); + frac |= j; + FP_TOF(exp, DBL_EXP_BIAS, frac, f0, f1, f2, 0); +} + +/* + * 128-bit extended -> fpn. + */ +int +fpu_qtof(fp, i, j, k, l) + register struct fpn *fp; + register u_int i, j, k, l; +{ + register int exp; + register u_int frac, f0, f1, f2, f3; +#define EXT_SHIFT (-(EXT_FRACBITS - 3 * 32 - FP_LG)) /* left shift! */ + + /* + * Note that ext and fpn `line up', hence no shifting needed. + */ + exp = (i >> (32 - 1 - EXT_EXPBITS)) & mask(EXT_EXPBITS); + frac = i & mask(EXT_FRACBITS - 3 * 32); + f0 = (frac << EXT_SHIFT) | (j >> (32 - EXT_SHIFT)); + f1 = (j << EXT_SHIFT) | (k >> (32 - EXT_SHIFT)); + f2 = (k << EXT_SHIFT) | (l >> (32 - EXT_SHIFT)); + f3 = l << EXT_SHIFT; + frac |= j | k | l; + FP_TOF(exp, EXT_EXP_BIAS, frac, f0, f1, f2, f3); +} + +/* + * Explode the contents of a register / regpair / regquad. + * If the input is a signalling NaN, an NV (invalid) exception + * will be set. (Note that nothing but NV can occur until ALU + * operations are performed.) + */ +void +fpu_explode(fe, fp, type, reg) + register struct fpemu *fe; + register struct fpn *fp; + int type, reg; +{ + register u_int s, *space; +#ifdef SUN4U + u_int64_t l, *xspace; + + xspace = (u_int64_t *)&fe->fe_fpstate->fs_regs[reg & ~1]; + l = xspace[0]; +#endif /* SUN4U */ + space = &fe->fe_fpstate->fs_regs[reg]; + s = space[0]; + fp->fp_sign = s >> 31; + fp->fp_sticky = 0; + switch (type) { +#ifdef SUN4U + case FTYPE_LNG: + s = fpu_xtof(fp, l); + break; +#endif /* SUN4U */ + + case FTYPE_INT: + s = fpu_itof(fp, s); + break; + + case FTYPE_SNG: + s = fpu_stof(fp, s); + break; + + case FTYPE_DBL: + s = fpu_dtof(fp, s, space[1]); + break; + + case FTYPE_EXT: + s = fpu_qtof(fp, s, space[1], space[2], space[3]); + break; + + default: + panic("fpu_explode"); + } + + if (s == FPC_QNAN && (fp->fp_mant[0] & FP_QUIETBIT) == 0) { + /* + * Input is a signalling NaN. All operations that return + * an input NaN operand put it through a ``NaN conversion'', + * which basically just means ``turn on the quiet bit''. + * We do this here so that all NaNs internally look quiet + * (we can tell signalling ones by their class). + */ + fp->fp_mant[0] |= FP_QUIETBIT; + fe->fe_cx = FSR_NV; /* assert invalid operand */ + s = FPC_SNAN; + } + fp->fp_class = s; + DPRINTF(FPE_REG, ("fpu_explode: %%%c%d => ", (type == FTYPE_LNG) ? 'x' : + ((type == FTYPE_INT) ? 'i' : + ((type == FTYPE_SNG) ? 's' : + ((type == FTYPE_DBL) ? 'd' : + ((type == FTYPE_EXT) ? 'q' : '?')))), + reg)); + DUMPFPN(FPE_REG, fp); + DPRINTF(FPE_REG, ("\n")); +} diff --git a/sys/arch/sparc64/fpu/fpu_extern.h b/sys/arch/sparc64/fpu/fpu_extern.h new file mode 100644 index 00000000000..633c435efdb --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_extern.h @@ -0,0 +1,100 @@ +/* $OpenBSD: fpu_extern.h,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_extern.h,v 1.4 2000/08/03 18:32:08 eeh Exp $ */ + +/*- + * Copyright (c) 1995 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Christos Zoulas. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the NetBSD + * Foundation, Inc. and its contributors. + * 4. Neither the name of The NetBSD Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +struct proc; +#ifndef SUN4U +struct fpstate; +struct trapframe; +#else /* SUN4U */ +struct fpstate64; +struct trapframe64; +#endif /* SUN4U */ +union instr; +struct fpemu; +struct fpn; + +/* fpu.c */ +#ifndef SUN4U +void fpu_cleanup __P((struct proc *, struct fpstate *)); +int fpu_emulate __P((struct proc *, struct trapframe *, struct fpstate *)); +#else /* SUN4U */ +void fpu_cleanup __P((struct proc *, struct fpstate64 *)); +int fpu_emulate __P((struct proc *, struct trapframe64 *, struct fpstate64 *)); +#endif /* SUN4U */ +int fpu_execute __P((struct fpemu *, union instr)); + +/* fpu_add.c */ +struct fpn *fpu_add __P((struct fpemu *)); + +/* fpu_compare.c */ +void fpu_compare __P((struct fpemu *, int)); + +/* fpu_div.c */ +struct fpn *fpu_div __P((struct fpemu *)); + +/* fpu_explode.c */ +int fpu_itof __P((struct fpn *, u_int)); +#ifdef SUN4U +int fpu_xtof __P((struct fpn *, u_int64_t)); +#endif /* SUN4U */ +int fpu_stof __P((struct fpn *, u_int)); +int fpu_dtof __P((struct fpn *, u_int, u_int )); +int fpu_qtof __P((struct fpn *, u_int, u_int , u_int , u_int )); +void fpu_explode __P((struct fpemu *, struct fpn *, int, int )); + +/* fpu_implode.c */ +u_int fpu_ftoi __P((struct fpemu *, struct fpn *)); +#ifdef SUN4U +u_int fpu_ftox __P((struct fpemu *, struct fpn *, u_int *)); +#endif /* SUN4U */ +u_int fpu_ftos __P((struct fpemu *, struct fpn *)); +u_int fpu_ftod __P((struct fpemu *, struct fpn *, u_int *)); +u_int fpu_ftoq __P((struct fpemu *, struct fpn *, u_int *)); +void fpu_implode __P((struct fpemu *, struct fpn *, int, u_int *)); + +/* fpu_mul.c */ +struct fpn *fpu_mul __P((struct fpemu *)); + +/* fpu_sqrt.c */ +struct fpn *fpu_sqrt __P((struct fpemu *)); + +/* fpu_subr.c */ +int fpu_shr __P((register struct fpn *, register int)); +void fpu_norm __P((register struct fpn *)); +struct fpn *fpu_newnan __P((register struct fpemu *)); diff --git a/sys/arch/sparc64/fpu/fpu_implode.c b/sys/arch/sparc64/fpu/fpu_implode.c new file mode 100644 index 00000000000..1b7522b0637 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_implode.c @@ -0,0 +1,535 @@ +/* $OpenBSD: fpu_implode.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_implode.c,v 1.7 2000/08/03 18:32:08 eeh Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_implode.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * FPU subroutines: `implode' internal format numbers into the machine's + * `packed binary' format. + */ + +#include <sys/types.h> +#include <sys/systm.h> + +#include <machine/ieee.h> +#include <machine/instr.h> +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> +#include <sparc64/fpu/fpu_extern.h> + +static int round __P((register struct fpemu *, register struct fpn *)); +static int toinf __P((struct fpemu *, int)); + +/* + * Round a number (algorithm from Motorola MC68882 manual, modified for + * our internal format). Set inexact exception if rounding is required. + * Return true iff we rounded up. + * + * After rounding, we discard the guard and round bits by shifting right + * 2 bits (a la fpu_shr(), but we do not bother with fp->fp_sticky). + * This saves effort later. + * + * Note that we may leave the value 2.0 in fp->fp_mant; it is the caller's + * responsibility to fix this if necessary. + */ +static int +round(register struct fpemu *fe, register struct fpn *fp) +{ + register u_int m0, m1, m2, m3; + register int gr, s; + + m0 = fp->fp_mant[0]; + m1 = fp->fp_mant[1]; + m2 = fp->fp_mant[2]; + m3 = fp->fp_mant[3]; + gr = m3 & 3; + s = fp->fp_sticky; + + /* mant >>= FP_NG */ + m3 = (m3 >> FP_NG) | (m2 << (32 - FP_NG)); + m2 = (m2 >> FP_NG) | (m1 << (32 - FP_NG)); + m1 = (m1 >> FP_NG) | (m0 << (32 - FP_NG)); + m0 >>= FP_NG; + + if ((gr | s) == 0) /* result is exact: no rounding needed */ + goto rounddown; + + fe->fe_cx |= FSR_NX; /* inexact */ + + /* Go to rounddown to round down; break to round up. */ + switch ((fe->fe_fsr >> FSR_RD_SHIFT) & FSR_RD_MASK) { + + case FSR_RD_RN: + default: + /* + * Round only if guard is set (gr & 2). If guard is set, + * but round & sticky both clear, then we want to round + * but have a tie, so round to even, i.e., add 1 iff odd. + */ + if ((gr & 2) == 0) + goto rounddown; + if ((gr & 1) || fp->fp_sticky || (m3 & 1)) + break; + goto rounddown; + + case FSR_RD_RZ: + /* Round towards zero, i.e., down. */ + goto rounddown; + + case FSR_RD_RM: + /* Round towards -Inf: up if negative, down if positive. */ + if (fp->fp_sign) + break; + goto rounddown; + + case FSR_RD_RP: + /* Round towards +Inf: up if positive, down otherwise. */ + if (!fp->fp_sign) + break; + goto rounddown; + } + + /* Bump low bit of mantissa, with carry. */ + FPU_ADDS(m3, m3, 1); + FPU_ADDCS(m2, m2, 0); + FPU_ADDCS(m1, m1, 0); + FPU_ADDC(m0, m0, 0); + fp->fp_mant[0] = m0; + fp->fp_mant[1] = m1; + fp->fp_mant[2] = m2; + fp->fp_mant[3] = m3; + return (1); + +rounddown: + fp->fp_mant[0] = m0; + fp->fp_mant[1] = m1; + fp->fp_mant[2] = m2; + fp->fp_mant[3] = m3; + return (0); +} + +/* + * For overflow: return true if overflow is to go to +/-Inf, according + * to the sign of the overflowing result. If false, overflow is to go + * to the largest magnitude value instead. + */ +static int +toinf(struct fpemu *fe, int sign) +{ + int inf; + + /* look at rounding direction */ + switch ((fe->fe_fsr >> FSR_RD_SHIFT) & FSR_RD_MASK) { + + default: + case FSR_RD_RN: /* the nearest value is always Inf */ + inf = 1; + break; + + case FSR_RD_RZ: /* toward 0 => never towards Inf */ + inf = 0; + break; + + case FSR_RD_RP: /* toward +Inf iff positive */ + inf = sign == 0; + break; + + case FSR_RD_RM: /* toward -Inf iff negative */ + inf = sign; + break; + } + return (inf); +} + +/* + * fpn -> int (int value returned as return value). + * + * N.B.: this conversion always rounds towards zero (this is a peculiarity + * of the SPARC instruction set). + */ +u_int +fpu_ftoi(fe, fp) + struct fpemu *fe; + register struct fpn *fp; +{ + register u_int i; + register int sign, exp; + + sign = fp->fp_sign; + switch (fp->fp_class) { + + case FPC_ZERO: + return (0); + + case FPC_NUM: + /* + * If exp >= 2^32, overflow. Otherwise shift value right + * into last mantissa word (this will not exceed 0xffffffff), + * shifting any guard and round bits out into the sticky + * bit. Then ``round'' towards zero, i.e., just set an + * inexact exception if sticky is set (see round()). + * If the result is > 0x80000000, or is positive and equals + * 0x80000000, overflow; otherwise the last fraction word + * is the result. + */ + if ((exp = fp->fp_exp) >= 32) + break; + /* NB: the following includes exp < 0 cases */ + if (fpu_shr(fp, FP_NMANT - 1 - exp) != 0) + fe->fe_cx |= FSR_NX; + i = fp->fp_mant[3]; + if (i >= ((u_int)0x80000000 + sign)) + break; + return (sign ? -i : i); + + default: /* Inf, qNaN, sNaN */ + break; + } + /* overflow: replace any inexact exception with invalid */ + fe->fe_cx = (fe->fe_cx & ~FSR_NX) | FSR_NV; + return (0x7fffffff + sign); +} + +#ifdef SUN4U +/* + * fpn -> extended int (high bits of int value returned as return value). + * + * N.B.: this conversion always rounds towards zero (this is a peculiarity + * of the SPARC instruction set). + */ +u_int +fpu_ftox(fe, fp, res) + struct fpemu *fe; + register struct fpn *fp; + u_int *res; +{ + register u_int64_t i; + register int sign, exp; + + sign = fp->fp_sign; + switch (fp->fp_class) { + + case FPC_ZERO: + res[1] = 0; + return (0); + + case FPC_NUM: + /* + * If exp >= 2^64, overflow. Otherwise shift value right + * into last mantissa word (this will not exceed 0xffffffffffffffff), + * shifting any guard and round bits out into the sticky + * bit. Then ``round'' towards zero, i.e., just set an + * inexact exception if sticky is set (see round()). + * If the result is > 0x8000000000000000, or is positive and equals + * 0x8000000000000000, overflow; otherwise the last fraction word + * is the result. + */ + if ((exp = fp->fp_exp) >= 64) + break; + /* NB: the following includes exp < 0 cases */ + if (fpu_shr(fp, FP_NMANT - 1 - exp) != 0) + fe->fe_cx |= FSR_NX; + i = ((u_int64_t)fp->fp_mant[2]<<32)|fp->fp_mant[3]; + if (i >= ((u_int64_t)0x8000000000000000LL + sign)) + break; + return (sign ? -i : i); + + default: /* Inf, qNaN, sNaN */ + break; + } + /* overflow: replace any inexact exception with invalid */ + fe->fe_cx = (fe->fe_cx & ~FSR_NX) | FSR_NV; + return (0x7fffffffffffffffLL + sign); +} +#endif /* SUN4U */ + +/* + * fpn -> single (32 bit single returned as return value). + * We assume <= 29 bits in a single-precision fraction (1.f part). + */ +u_int +fpu_ftos(fe, fp) + struct fpemu *fe; + register struct fpn *fp; +{ + register u_int sign = fp->fp_sign << 31; + register int exp; + +#define SNG_EXP(e) ((e) << SNG_FRACBITS) /* makes e an exponent */ +#define SNG_MASK (SNG_EXP(1) - 1) /* mask for fraction */ + + /* Take care of non-numbers first. */ + if (ISNAN(fp)) { + /* + * Preserve upper bits of NaN, per SPARC V8 appendix N. + * Note that fp->fp_mant[0] has the quiet bit set, + * even if it is classified as a signalling NaN. + */ + (void) fpu_shr(fp, FP_NMANT - 1 - SNG_FRACBITS); + exp = SNG_EXP_INFNAN; + goto done; + } + if (ISINF(fp)) + return (sign | SNG_EXP(SNG_EXP_INFNAN)); + if (ISZERO(fp)) + return (sign); + + /* + * Normals (including subnormals). Drop all the fraction bits + * (including the explicit ``implied'' 1 bit) down into the + * single-precision range. If the number is subnormal, move + * the ``implied'' 1 into the explicit range as well, and shift + * right to introduce leading zeroes. Rounding then acts + * differently for normals and subnormals: the largest subnormal + * may round to the smallest normal (1.0 x 2^minexp), or may + * remain subnormal. In the latter case, signal an underflow + * if the result was inexact or if underflow traps are enabled. + * + * Rounding a normal, on the other hand, always produces another + * normal (although either way the result might be too big for + * single precision, and cause an overflow). If rounding a + * normal produces 2.0 in the fraction, we need not adjust that + * fraction at all, since both 1.0 and 2.0 are zero under the + * fraction mask. + * + * Note that the guard and round bits vanish from the number after + * rounding. + */ + if ((exp = fp->fp_exp + SNG_EXP_BIAS) <= 0) { /* subnormal */ + /* -NG for g,r; -SNG_FRACBITS-exp for fraction */ + (void) fpu_shr(fp, FP_NMANT - FP_NG - SNG_FRACBITS - exp); + if (round(fe, fp) && fp->fp_mant[3] == SNG_EXP(1)) + return (sign | SNG_EXP(1) | 0); + if ((fe->fe_cx & FSR_NX) || + (fe->fe_fsr & (FSR_UF << FSR_TEM_SHIFT))) + fe->fe_cx |= FSR_UF; + return (sign | SNG_EXP(0) | fp->fp_mant[3]); + } + /* -FP_NG for g,r; -1 for implied 1; -SNG_FRACBITS for fraction */ + (void) fpu_shr(fp, FP_NMANT - FP_NG - 1 - SNG_FRACBITS); +#ifdef DIAGNOSTIC + if ((fp->fp_mant[3] & SNG_EXP(1 << FP_NG)) == 0) + panic("fpu_ftos"); +#endif + if (round(fe, fp) && fp->fp_mant[3] == SNG_EXP(2)) + exp++; + if (exp >= SNG_EXP_INFNAN) { + /* overflow to inf or to max single */ + fe->fe_cx |= FSR_OF | FSR_NX; + if (toinf(fe, sign)) + return (sign | SNG_EXP(SNG_EXP_INFNAN)); + return (sign | SNG_EXP(SNG_EXP_INFNAN - 1) | SNG_MASK); + } +done: + /* phew, made it */ + return (sign | SNG_EXP(exp) | (fp->fp_mant[3] & SNG_MASK)); +} + +/* + * fpn -> double (32 bit high-order result returned; 32-bit low order result + * left in res[1]). Assumes <= 61 bits in double precision fraction. + * + * This code mimics fpu_ftos; see it for comments. + */ +u_int +fpu_ftod(fe, fp, res) + struct fpemu *fe; + register struct fpn *fp; + u_int *res; +{ + register u_int sign = fp->fp_sign << 31; + register int exp; + +#define DBL_EXP(e) ((e) << (DBL_FRACBITS & 31)) +#define DBL_MASK (DBL_EXP(1) - 1) + + if (ISNAN(fp)) { + (void) fpu_shr(fp, FP_NMANT - 1 - DBL_FRACBITS); + exp = DBL_EXP_INFNAN; + goto done; + } + if (ISINF(fp)) { + sign |= DBL_EXP(DBL_EXP_INFNAN); + goto zero; + } + if (ISZERO(fp)) { +zero: res[1] = 0; + return (sign); + } + + if ((exp = fp->fp_exp + DBL_EXP_BIAS) <= 0) { + (void) fpu_shr(fp, FP_NMANT - FP_NG - DBL_FRACBITS - exp); + if (round(fe, fp) && fp->fp_mant[2] == DBL_EXP(1)) { + res[1] = 0; + return (sign | DBL_EXP(1) | 0); + } + if ((fe->fe_cx & FSR_NX) || + (fe->fe_fsr & (FSR_UF << FSR_TEM_SHIFT))) + fe->fe_cx |= FSR_UF; + exp = 0; + goto done; + } + (void) fpu_shr(fp, FP_NMANT - FP_NG - 1 - DBL_FRACBITS); + if (round(fe, fp) && fp->fp_mant[2] == DBL_EXP(2)) + exp++; + if (exp >= DBL_EXP_INFNAN) { + fe->fe_cx |= FSR_OF | FSR_NX; + if (toinf(fe, sign)) { + res[1] = 0; + return (sign | DBL_EXP(DBL_EXP_INFNAN) | 0); + } + res[1] = ~0; + return (sign | DBL_EXP(DBL_EXP_INFNAN) | DBL_MASK); + } +done: + res[1] = fp->fp_mant[3]; + return (sign | DBL_EXP(exp) | (fp->fp_mant[2] & DBL_MASK)); +} + +/* + * fpn -> extended (32 bit high-order result returned; low-order fraction + * words left in res[1]..res[3]). Like ftod, which is like ftos ... but + * our internal format *is* extended precision, plus 2 bits for guard/round, + * so we can avoid a small bit of work. + */ +u_int +fpu_ftoq(fe, fp, res) + struct fpemu *fe; + register struct fpn *fp; + u_int *res; +{ + register u_int sign = fp->fp_sign << 31; + register int exp; + +#define EXT_EXP(e) ((e) << (EXT_FRACBITS & 31)) +#define EXT_MASK (EXT_EXP(1) - 1) + + if (ISNAN(fp)) { + (void) fpu_shr(fp, 2); /* since we are not rounding */ + exp = EXT_EXP_INFNAN; + goto done; + } + if (ISINF(fp)) { + sign |= EXT_EXP(EXT_EXP_INFNAN); + goto zero; + } + if (ISZERO(fp)) { +zero: res[1] = res[2] = res[3] = 0; + return (sign); + } + + if ((exp = fp->fp_exp + EXT_EXP_BIAS) <= 0) { + (void) fpu_shr(fp, FP_NMANT - FP_NG - EXT_FRACBITS - exp); + if (round(fe, fp) && fp->fp_mant[0] == EXT_EXP(1)) { + res[1] = res[2] = res[3] = 0; + return (sign | EXT_EXP(1) | 0); + } + if ((fe->fe_cx & FSR_NX) || + (fe->fe_fsr & (FSR_UF << FSR_TEM_SHIFT))) + fe->fe_cx |= FSR_UF; + exp = 0; + goto done; + } + /* Since internal == extended, no need to shift here. */ + if (round(fe, fp) && fp->fp_mant[0] == EXT_EXP(2)) + exp++; + if (exp >= EXT_EXP_INFNAN) { + fe->fe_cx |= FSR_OF | FSR_NX; + if (toinf(fe, sign)) { + res[1] = res[2] = res[3] = 0; + return (sign | EXT_EXP(EXT_EXP_INFNAN) | 0); + } + res[1] = res[2] = res[3] = ~0; + return (sign | EXT_EXP(EXT_EXP_INFNAN) | EXT_MASK); + } +done: + res[1] = fp->fp_mant[1]; + res[2] = fp->fp_mant[2]; + res[3] = fp->fp_mant[3]; + return (sign | EXT_EXP(exp) | (fp->fp_mant[0] & EXT_MASK)); +} + +/* + * Implode an fpn, writing the result into the given space. + */ +void +fpu_implode(fe, fp, type, space) + struct fpemu *fe; + register struct fpn *fp; + int type; + register u_int *space; +{ + + switch (type) { + +#ifdef SUN4U + case FTYPE_LNG: + space[0] = fpu_ftox(fe, fp, space); + break; +#endif /* SUN4U */ + + case FTYPE_INT: + space[0] = fpu_ftoi(fe, fp); + break; + + case FTYPE_SNG: + space[0] = fpu_ftos(fe, fp); + break; + + case FTYPE_DBL: + space[0] = fpu_ftod(fe, fp, space); + break; + + case FTYPE_EXT: + /* funky rounding precision options ?? */ + space[0] = fpu_ftoq(fe, fp, space); + break; + + default: + panic("fpu_implode"); + } +} diff --git a/sys/arch/sparc64/fpu/fpu_mul.c b/sys/arch/sparc64/fpu/fpu_mul.c new file mode 100644 index 00000000000..150120b00e6 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_mul.c @@ -0,0 +1,227 @@ +/* $OpenBSD: fpu_mul.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_mul.c,v 1.2 1994/11/20 20:52:44 deraadt Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_mul.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * Perform an FPU multiply (return x * y). + */ + +#include <sys/types.h> + +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> + +/* + * The multiplication algorithm for normal numbers is as follows: + * + * The fraction of the product is built in the usual stepwise fashion. + * Each step consists of shifting the accumulator right one bit + * (maintaining any guard bits) and, if the next bit in y is set, + * adding the multiplicand (x) to the accumulator. Then, in any case, + * we advance one bit leftward in y. Algorithmically: + * + * A = 0; + * for (bit = 0; bit < FP_NMANT; bit++) { + * sticky |= A & 1, A >>= 1; + * if (Y & (1 << bit)) + * A += X; + * } + * + * (X and Y here represent the mantissas of x and y respectively.) + * The resultant accumulator (A) is the product's mantissa. It may + * be as large as 11.11111... in binary and hence may need to be + * shifted right, but at most one bit. + * + * Since we do not have efficient multiword arithmetic, we code the + * accumulator as four separate words, just like any other mantissa. + * We use local `register' variables in the hope that this is faster + * than memory. We keep x->fp_mant in locals for the same reason. + * + * In the algorithm above, the bits in y are inspected one at a time. + * We will pick them up 32 at a time and then deal with those 32, one + * at a time. Note, however, that we know several things about y: + * + * - the guard and round bits at the bottom are sure to be zero; + * + * - often many low bits are zero (y is often from a single or double + * precision source); + * + * - bit FP_NMANT-1 is set, and FP_1*2 fits in a word. + * + * We can also test for 32-zero-bits swiftly. In this case, the center + * part of the loop---setting sticky, shifting A, and not adding---will + * run 32 times without adding X to A. We can do a 32-bit shift faster + * by simply moving words. Since zeros are common, we optimize this case. + * Furthermore, since A is initially zero, we can omit the shift as well + * until we reach a nonzero word. + */ +struct fpn * +fpu_mul(fe) + register struct fpemu *fe; +{ + register struct fpn *x = &fe->fe_f1, *y = &fe->fe_f2; + register u_int a3, a2, a1, a0, x3, x2, x1, x0, bit, m; + register int sticky; + FPU_DECL_CARRY + + /* + * Put the `heavier' operand on the right (see fpu_emu.h). + * Then we will have one of the following cases, taken in the + * following order: + * + * - y = NaN. Implied: if only one is a signalling NaN, y is. + * The result is y. + * - y = Inf. Implied: x != NaN (is 0, number, or Inf: the NaN + * case was taken care of earlier). + * If x = 0, the result is NaN. Otherwise the result + * is y, with its sign reversed if x is negative. + * - x = 0. Implied: y is 0 or number. + * The result is 0 (with XORed sign as usual). + * - other. Implied: both x and y are numbers. + * The result is x * y (XOR sign, multiply bits, add exponents). + */ + ORDER(x, y); + if (ISNAN(y)) { + y->fp_sign ^= x->fp_sign; + return (y); + } + if (ISINF(y)) { + if (ISZERO(x)) + return (fpu_newnan(fe)); + y->fp_sign ^= x->fp_sign; + return (y); + } + if (ISZERO(x)) { + x->fp_sign ^= y->fp_sign; + return (x); + } + + /* + * Setup. In the code below, the mask `m' will hold the current + * mantissa byte from y. The variable `bit' denotes the bit + * within m. We also define some macros to deal with everything. + */ + x3 = x->fp_mant[3]; + x2 = x->fp_mant[2]; + x1 = x->fp_mant[1]; + x0 = x->fp_mant[0]; + sticky = a3 = a2 = a1 = a0 = 0; + +#define ADD /* A += X */ \ + FPU_ADDS(a3, a3, x3); \ + FPU_ADDCS(a2, a2, x2); \ + FPU_ADDCS(a1, a1, x1); \ + FPU_ADDC(a0, a0, x0) + +#define SHR1 /* A >>= 1, with sticky */ \ + sticky |= a3 & 1, a3 = (a3 >> 1) | (a2 << 31), \ + a2 = (a2 >> 1) | (a1 << 31), a1 = (a1 >> 1) | (a0 << 31), a0 >>= 1 + +#define SHR32 /* A >>= 32, with sticky */ \ + sticky |= a3, a3 = a2, a2 = a1, a1 = a0, a0 = 0 + +#define STEP /* each 1-bit step of the multiplication */ \ + SHR1; if (bit & m) { ADD; }; bit <<= 1 + + /* + * We are ready to begin. The multiply loop runs once for each + * of the four 32-bit words. Some words, however, are special. + * As noted above, the low order bits of Y are often zero. Even + * if not, the first loop can certainly skip the guard bits. + * The last word of y has its highest 1-bit in position FP_NMANT-1, + * so we stop the loop when we move past that bit. + */ + if ((m = y->fp_mant[3]) == 0) { + /* SHR32; */ /* unneeded since A==0 */ + } else { + bit = 1 << FP_NG; + do { + STEP; + } while (bit != 0); + } + if ((m = y->fp_mant[2]) == 0) { + SHR32; + } else { + bit = 1; + do { + STEP; + } while (bit != 0); + } + if ((m = y->fp_mant[1]) == 0) { + SHR32; + } else { + bit = 1; + do { + STEP; + } while (bit != 0); + } + m = y->fp_mant[0]; /* definitely != 0 */ + bit = 1; + do { + STEP; + } while (bit <= m); + + /* + * Done with mantissa calculation. Get exponent and handle + * 11.111...1 case, then put result in place. We reuse x since + * it already has the right class (FP_NUM). + */ + m = x->fp_exp + y->fp_exp; + if (a0 >= FP_2) { + SHR1; + m++; + } + x->fp_sign ^= y->fp_sign; + x->fp_exp = m; + x->fp_sticky = sticky; + x->fp_mant[3] = a3; + x->fp_mant[2] = a2; + x->fp_mant[1] = a1; + x->fp_mant[0] = a0; + return (x); +} diff --git a/sys/arch/sparc64/fpu/fpu_sqrt.c b/sys/arch/sparc64/fpu/fpu_sqrt.c new file mode 100644 index 00000000000..9b296814187 --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_sqrt.c @@ -0,0 +1,398 @@ +/* $OpenBSD: fpu_sqrt.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_sqrt.c,v 1.2 1994/11/20 20:52:46 deraadt Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_sqrt.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * Perform an FPU square root (return sqrt(x)). + */ + +#include <sys/types.h> + +#include <machine/reg.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> + +/* + * Our task is to calculate the square root of a floating point number x0. + * This number x normally has the form: + * + * exp + * x = mant * 2 (where 1 <= mant < 2 and exp is an integer) + * + * This can be left as it stands, or the mantissa can be doubled and the + * exponent decremented: + * + * exp-1 + * x = (2 * mant) * 2 (where 2 <= 2 * mant < 4) + * + * If the exponent `exp' is even, the square root of the number is best + * handled using the first form, and is by definition equal to: + * + * exp/2 + * sqrt(x) = sqrt(mant) * 2 + * + * If exp is odd, on the other hand, it is convenient to use the second + * form, giving: + * + * (exp-1)/2 + * sqrt(x) = sqrt(2 * mant) * 2 + * + * In the first case, we have + * + * 1 <= mant < 2 + * + * and therefore + * + * sqrt(1) <= sqrt(mant) < sqrt(2) + * + * while in the second case we have + * + * 2 <= 2*mant < 4 + * + * and therefore + * + * sqrt(2) <= sqrt(2*mant) < sqrt(4) + * + * so that in any case, we are sure that + * + * sqrt(1) <= sqrt(n * mant) < sqrt(4), n = 1 or 2 + * + * or + * + * 1 <= sqrt(n * mant) < 2, n = 1 or 2. + * + * This root is therefore a properly formed mantissa for a floating + * point number. The exponent of sqrt(x) is either exp/2 or (exp-1)/2 + * as above. This leaves us with the problem of finding the square root + * of a fixed-point number in the range [1..4). + * + * Though it may not be instantly obvious, the following square root + * algorithm works for any integer x of an even number of bits, provided + * that no overflows occur: + * + * let q = 0 + * for k = NBITS-1 to 0 step -1 do -- for each digit in the answer... + * x *= 2 -- multiply by radix, for next digit + * if x >= 2q + 2^k then -- if adding 2^k does not + * x -= 2q + 2^k -- exceed the correct root, + * q += 2^k -- add 2^k and adjust x + * fi + * done + * sqrt = q / 2^(NBITS/2) -- (and any remainder is in x) + * + * If NBITS is odd (so that k is initially even), we can just add another + * zero bit at the top of x. Doing so means that q is not going to acquire + * a 1 bit in the first trip around the loop (since x0 < 2^NBITS). If the + * final value in x is not needed, or can be off by a factor of 2, this is + * equivalant to moving the `x *= 2' step to the bottom of the loop: + * + * for k = NBITS-1 to 0 step -1 do if ... fi; x *= 2; done + * + * and the result q will then be sqrt(x0) * 2^floor(NBITS / 2). + * (Since the algorithm is destructive on x, we will call x's initial + * value, for which q is some power of two times its square root, x0.) + * + * If we insert a loop invariant y = 2q, we can then rewrite this using + * C notation as: + * + * q = y = 0; x = x0; + * for (k = NBITS; --k >= 0;) { + * #if (NBITS is even) + * x *= 2; + * #endif + * t = y + (1 << k); + * if (x >= t) { + * x -= t; + * q += 1 << k; + * y += 1 << (k + 1); + * } + * #if (NBITS is odd) + * x *= 2; + * #endif + * } + * + * If x0 is fixed point, rather than an integer, we can simply alter the + * scale factor between q and sqrt(x0). As it happens, we can easily arrange + * for the scale factor to be 2**0 or 1, so that sqrt(x0) == q. + * + * In our case, however, x0 (and therefore x, y, q, and t) are multiword + * integers, which adds some complication. But note that q is built one + * bit at a time, from the top down, and is not used itself in the loop + * (we use 2q as held in y instead). This means we can build our answer + * in an integer, one word at a time, which saves a bit of work. Also, + * since 1 << k is always a `new' bit in q, 1 << k and 1 << (k+1) are + * `new' bits in y and we can set them with an `or' operation rather than + * a full-blown multiword add. + * + * We are almost done, except for one snag. We must prove that none of our + * intermediate calculations can overflow. We know that x0 is in [1..4) + * and therefore the square root in q will be in [1..2), but what about x, + * y, and t? + * + * We know that y = 2q at the beginning of each loop. (The relation only + * fails temporarily while y and q are being updated.) Since q < 2, y < 4. + * The sum in t can, in our case, be as much as y+(1<<1) = y+2 < 6, and. + * Furthermore, we can prove with a bit of work that x never exceeds y by + * more than 2, so that even after doubling, 0 <= x < 8. (This is left as + * an exercise to the reader, mostly because I have become tired of working + * on this comment.) + * + * If our floating point mantissas (which are of the form 1.frac) occupy + * B+1 bits, our largest intermediary needs at most B+3 bits, or two extra. + * In fact, we want even one more bit (for a carry, to avoid compares), or + * three extra. There is a comment in fpu_emu.h reminding maintainers of + * this, so we have some justification in assuming it. + */ +struct fpn * +fpu_sqrt(fe) + struct fpemu *fe; +{ + register struct fpn *x = &fe->fe_f1; + register u_int bit, q, tt; + register u_int x0, x1, x2, x3; + register u_int y0, y1, y2, y3; + register u_int d0, d1, d2, d3; + register int e; + + /* + * Take care of special cases first. In order: + * + * sqrt(NaN) = NaN + * sqrt(+0) = +0 + * sqrt(-0) = -0 + * sqrt(x < 0) = NaN (including sqrt(-Inf)) + * sqrt(+Inf) = +Inf + * + * Then all that remains are numbers with mantissas in [1..2). + */ + if (ISNAN(x) || ISZERO(x)) + return (x); + if (x->fp_sign) + return (fpu_newnan(fe)); + if (ISINF(x)) + return (x); + + /* + * Calculate result exponent. As noted above, this may involve + * doubling the mantissa. We will also need to double x each + * time around the loop, so we define a macro for this here, and + * we break out the multiword mantissa. + */ +#ifdef FPU_SHL1_BY_ADD +#define DOUBLE_X { \ + FPU_ADDS(x3, x3, x3); FPU_ADDCS(x2, x2, x2); \ + FPU_ADDCS(x1, x1, x1); FPU_ADDC(x0, x0, x0); \ +} +#else +#define DOUBLE_X { \ + x0 = (x0 << 1) | (x1 >> 31); x1 = (x1 << 1) | (x2 >> 31); \ + x2 = (x2 << 1) | (x3 >> 31); x3 <<= 1; \ +} +#endif +#if (FP_NMANT & 1) != 0 +# define ODD_DOUBLE DOUBLE_X +# define EVEN_DOUBLE /* nothing */ +#else +# define ODD_DOUBLE /* nothing */ +# define EVEN_DOUBLE DOUBLE_X +#endif + x0 = x->fp_mant[0]; + x1 = x->fp_mant[1]; + x2 = x->fp_mant[2]; + x3 = x->fp_mant[3]; + e = x->fp_exp; + if (e & 1) /* exponent is odd; use sqrt(2mant) */ + DOUBLE_X; + /* THE FOLLOWING ASSUMES THAT RIGHT SHIFT DOES SIGN EXTENSION */ + x->fp_exp = e >> 1; /* calculates (e&1 ? (e-1)/2 : e/2 */ + + /* + * Now calculate the mantissa root. Since x is now in [1..4), + * we know that the first trip around the loop will definitely + * set the top bit in q, so we can do that manually and start + * the loop at the next bit down instead. We must be sure to + * double x correctly while doing the `known q=1.0'. + * + * We do this one mantissa-word at a time, as noted above, to + * save work. To avoid `(1 << 31) << 1', we also do the top bit + * outside of each per-word loop. + * + * The calculation `t = y + bit' breaks down into `t0 = y0, ..., + * t3 = y3, t? |= bit' for the appropriate word. Since the bit + * is always a `new' one, this means that three of the `t?'s are + * just the corresponding `y?'; we use `#define's here for this. + * The variable `tt' holds the actual `t?' variable. + */ + + /* calculate q0 */ +#define t0 tt + bit = FP_1; + EVEN_DOUBLE; + /* if (x >= (t0 = y0 | bit)) { */ /* always true */ + q = bit; + x0 -= bit; + y0 = bit << 1; + /* } */ + ODD_DOUBLE; + while ((bit >>= 1) != 0) { /* for remaining bits in q0 */ + EVEN_DOUBLE; + t0 = y0 | bit; /* t = y + bit */ + if (x0 >= t0) { /* if x >= t then */ + x0 -= t0; /* x -= t */ + q |= bit; /* q += bit */ + y0 |= bit << 1; /* y += bit << 1 */ + } + ODD_DOUBLE; + } + x->fp_mant[0] = q; +#undef t0 + + /* calculate q1. note (y0&1)==0. */ +#define t0 y0 +#define t1 tt + q = 0; + y1 = 0; + bit = 1 << 31; + EVEN_DOUBLE; + t1 = bit; + FPU_SUBS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); /* d = x - t */ + if ((int)d0 >= 0) { /* if d >= 0 (i.e., x >= t) then */ + x0 = d0, x1 = d1; /* x -= t */ + q = bit; /* q += bit */ + y0 |= 1; /* y += bit << 1 */ + } + ODD_DOUBLE; + while ((bit >>= 1) != 0) { /* for remaining bits in q1 */ + EVEN_DOUBLE; /* as before */ + t1 = y1 | bit; + FPU_SUBS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); + if ((int)d0 >= 0) { + x0 = d0, x1 = d1; + q |= bit; + y1 |= bit << 1; + } + ODD_DOUBLE; + } + x->fp_mant[1] = q; +#undef t1 + + /* calculate q2. note (y1&1)==0; y0 (aka t0) is fixed. */ +#define t1 y1 +#define t2 tt + q = 0; + y2 = 0; + bit = 1 << 31; + EVEN_DOUBLE; + t2 = bit; + FPU_SUBS(d2, x2, t2); + FPU_SUBCS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); + if ((int)d0 >= 0) { + x0 = d0, x1 = d1, x2 = d2; + q |= bit; + y1 |= 1; /* now t1, y1 are set in concrete */ + } + ODD_DOUBLE; + while ((bit >>= 1) != 0) { + EVEN_DOUBLE; + t2 = y2 | bit; + FPU_SUBS(d2, x2, t2); + FPU_SUBCS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); + if ((int)d0 >= 0) { + x0 = d0, x1 = d1, x2 = d2; + q |= bit; + y2 |= bit << 1; + } + ODD_DOUBLE; + } + x->fp_mant[2] = q; +#undef t2 + + /* calculate q3. y0, t0, y1, t1 all fixed; y2, t2, almost done. */ +#define t2 y2 +#define t3 tt + q = 0; + y3 = 0; + bit = 1 << 31; + EVEN_DOUBLE; + t3 = bit; + FPU_SUBS(d3, x3, t3); + FPU_SUBCS(d2, x2, t2); + FPU_SUBCS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); + ODD_DOUBLE; + if ((int)d0 >= 0) { + x0 = d0, x1 = d1, x2 = d2; + q |= bit; + y2 |= 1; + } + while ((bit >>= 1) != 0) { + EVEN_DOUBLE; + t3 = y3 | bit; + FPU_SUBS(d3, x3, t3); + FPU_SUBCS(d2, x2, t2); + FPU_SUBCS(d1, x1, t1); + FPU_SUBC(d0, x0, t0); + if ((int)d0 >= 0) { + x0 = d0, x1 = d1, x2 = d2; + q |= bit; + y3 |= bit << 1; + } + ODD_DOUBLE; + } + x->fp_mant[3] = q; + + /* + * The result, which includes guard and round bits, is exact iff + * x is now zero; any nonzero bits in x represent sticky bits. + */ + x->fp_sticky = x0 | x1 | x2 | x3; + return (x); +} diff --git a/sys/arch/sparc64/fpu/fpu_subr.c b/sys/arch/sparc64/fpu/fpu_subr.c new file mode 100644 index 00000000000..9d9903cd95a --- /dev/null +++ b/sys/arch/sparc64/fpu/fpu_subr.c @@ -0,0 +1,224 @@ +/* $OpenBSD: fpu_subr.c,v 1.1 2001/09/08 22:33:51 jason Exp $ */ +/* $NetBSD: fpu_subr.c,v 1.3 1996/03/14 19:42:01 christos Exp $ */ + +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Lawrence Berkeley Laboratory. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)fpu_subr.c 8.1 (Berkeley) 6/11/93 + */ + +/* + * FPU subroutines. + */ + +#include <sys/types.h> +#ifdef DIAGNOSTIC +#include <sys/systm.h> +#endif + +#include <machine/reg.h> +#include <machine/instr.h> + +#include <sparc64/fpu/fpu_arith.h> +#include <sparc64/fpu/fpu_emu.h> +#include <sparc64/fpu/fpu_extern.h> + +/* + * Shift the given number right rsh bits. Any bits that `fall off' will get + * shoved into the sticky field; we return the resulting sticky. Note that + * shifting NaNs is legal (this will never shift all bits out); a NaN's + * sticky field is ignored anyway. + */ +int +fpu_shr(register struct fpn *fp, register int rsh) +{ + register u_int m0, m1, m2, m3, s; + register int lsh; + +#ifdef DIAGNOSTIC + if (rsh <= 0 || (fp->fp_class != FPC_NUM && !ISNAN(fp))) + panic("fpu_rightshift 1"); +#endif + + m0 = fp->fp_mant[0]; + m1 = fp->fp_mant[1]; + m2 = fp->fp_mant[2]; + m3 = fp->fp_mant[3]; + + /* If shifting all the bits out, take a shortcut. */ + if (rsh >= FP_NMANT) { +#ifdef DIAGNOSTIC + if ((m0 | m1 | m2 | m3) == 0) + panic("fpu_rightshift 2"); +#endif + fp->fp_mant[0] = 0; + fp->fp_mant[1] = 0; + fp->fp_mant[2] = 0; + fp->fp_mant[3] = 0; +#ifdef notdef + if ((m0 | m1 | m2 | m3) == 0) + fp->fp_class = FPC_ZERO; + else +#endif + fp->fp_sticky = 1; + return (1); + } + + /* Squish out full words. */ + s = fp->fp_sticky; + if (rsh >= 32 * 3) { + s |= m3 | m2 | m1; + m3 = m0, m2 = 0, m1 = 0, m0 = 0; + } else if (rsh >= 32 * 2) { + s |= m3 | m2; + m3 = m1, m2 = m0, m1 = 0, m0 = 0; + } else if (rsh >= 32) { + s |= m3; + m3 = m2, m2 = m1, m1 = m0, m0 = 0; + } + + /* Handle any remaining partial word. */ + if ((rsh &= 31) != 0) { + lsh = 32 - rsh; + s |= m3 << lsh; + m3 = (m3 >> rsh) | (m2 << lsh); + m2 = (m2 >> rsh) | (m1 << lsh); + m1 = (m1 >> rsh) | (m0 << lsh); + m0 >>= rsh; + } + fp->fp_mant[0] = m0; + fp->fp_mant[1] = m1; + fp->fp_mant[2] = m2; + fp->fp_mant[3] = m3; + fp->fp_sticky = s; + return (s); +} + +/* + * Force a number to be normal, i.e., make its fraction have all zero + * bits before FP_1, then FP_1, then all 1 bits. This is used for denorms + * and (sometimes) for intermediate results. + * + * Internally, this may use a `supernormal' -- a number whose fp_mant + * is greater than or equal to 2.0 -- so as a side effect you can hand it + * a supernormal and it will fix it (provided fp->fp_mant[3] == 0). + */ +void +fpu_norm(register struct fpn *fp) +{ + register u_int m0, m1, m2, m3, top, sup, nrm; + register int lsh, rsh, exp; + + exp = fp->fp_exp; + m0 = fp->fp_mant[0]; + m1 = fp->fp_mant[1]; + m2 = fp->fp_mant[2]; + m3 = fp->fp_mant[3]; + + /* Handle severe subnormals with 32-bit moves. */ + if (m0 == 0) { + if (m1) + m0 = m1, m1 = m2, m2 = m3, m3 = 0, exp -= 32; + else if (m2) + m0 = m2, m1 = m3, m2 = 0, m3 = 0, exp -= 2 * 32; + else if (m3) + m0 = m3, m1 = 0, m2 = 0, m3 = 0, exp -= 3 * 32; + else { + fp->fp_class = FPC_ZERO; + return; + } + } + + /* Now fix any supernormal or remaining subnormal. */ + nrm = FP_1; + sup = nrm << 1; + if (m0 >= sup) { + /* + * We have a supernormal number. We need to shift it right. + * We may assume m3==0. + */ + for (rsh = 1, top = m0 >> 1; top >= sup; rsh++) /* XXX slow */ + top >>= 1; + exp += rsh; + lsh = 32 - rsh; + m3 = m2 << lsh; + m2 = (m2 >> rsh) | (m1 << lsh); + m1 = (m1 >> rsh) | (m0 << lsh); + m0 = top; + } else if (m0 < nrm) { + /* + * We have a regular denorm (a subnormal number), and need + * to shift it left. + */ + for (lsh = 1, top = m0 << 1; top < nrm; lsh++) /* XXX slow */ + top <<= 1; + exp -= lsh; + rsh = 32 - lsh; + m0 = top | (m1 >> rsh); + m1 = (m1 << lsh) | (m2 >> rsh); + m2 = (m2 << lsh) | (m3 >> rsh); + m3 <<= lsh; + } + + fp->fp_exp = exp; + fp->fp_mant[0] = m0; + fp->fp_mant[1] = m1; + fp->fp_mant[2] = m2; + fp->fp_mant[3] = m3; +} + +/* + * Concoct a `fresh' Quiet NaN per Appendix N. + * As a side effect, we set NV (invalid) for the current exceptions. + */ +struct fpn * +fpu_newnan(register struct fpemu *fe) +{ + register struct fpn *fp; + + fe->fe_cx = FSR_NV; + fp = &fe->fe_f3; + fp->fp_class = FPC_QNAN; + fp->fp_sign = 0; + fp->fp_mant[0] = FP_1 - 1; + fp->fp_mant[1] = fp->fp_mant[2] = fp->fp_mant[3] = ~0; + return (fp); +} |