math.c
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上传日期:2013-02-24
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- /* $Id: math.c,v 1.11 1999/12/20 05:02:25 davem Exp $
- * arch/sparc64/math-emu/math.c
- *
- * Copyright (C) 1997,1999 Jakub Jelinek (jj@ultra.linux.cz)
- * Copyright (C) 1999 David S. Miller (davem@redhat.com)
- *
- * Emulation routines originate from soft-fp package, which is part
- * of glibc and has appropriate copyrights in it.
- */
- #include <linux/types.h>
- #include <linux/sched.h>
- #include <asm/fpumacro.h>
- #include <asm/ptrace.h>
- #include <asm/uaccess.h>
- #include "sfp-util.h"
- #include <math-emu/soft-fp.h>
- #include <math-emu/single.h>
- #include <math-emu/double.h>
- #include <math-emu/quad.h>
- /* QUAD - ftt == 3 */
- #define FMOVQ 0x003
- #define FNEGQ 0x007
- #define FABSQ 0x00b
- #define FSQRTQ 0x02b
- #define FADDQ 0x043
- #define FSUBQ 0x047
- #define FMULQ 0x04b
- #define FDIVQ 0x04f
- #define FDMULQ 0x06e
- #define FQTOX 0x083
- #define FXTOQ 0x08c
- #define FQTOS 0x0c7
- #define FQTOD 0x0cb
- #define FITOQ 0x0cc
- #define FSTOQ 0x0cd
- #define FDTOQ 0x0ce
- #define FQTOI 0x0d3
- /* SUBNORMAL - ftt == 2 */
- #define FSQRTS 0x029
- #define FSQRTD 0x02a
- #define FADDS 0x041
- #define FADDD 0x042
- #define FSUBS 0x045
- #define FSUBD 0x046
- #define FMULS 0x049
- #define FMULD 0x04a
- #define FDIVS 0x04d
- #define FDIVD 0x04e
- #define FSMULD 0x069
- #define FSTOX 0x081
- #define FDTOX 0x082
- #define FDTOS 0x0c6
- #define FSTOD 0x0c9
- #define FSTOI 0x0d1
- #define FDTOI 0x0d2
- /* FPOP2 */
- #define FCMPQ 0x053
- #define FCMPEQ 0x057
- #define FMOVQ0 0x003
- #define FMOVQ1 0x043
- #define FMOVQ2 0x083
- #define FMOVQ3 0x0c3
- #define FMOVQI 0x103
- #define FMOVQX 0x183
- #define FMOVQZ 0x027
- #define FMOVQLE 0x047
- #define FMOVQLZ 0x067
- #define FMOVQNZ 0x0a7
- #define FMOVQGZ 0x0c7
- #define FMOVQGE 0x0e7
- #define FSR_TEM_SHIFT 23UL
- #define FSR_TEM_MASK (0x1fUL << FSR_TEM_SHIFT)
- #define FSR_AEXC_SHIFT 5UL
- #define FSR_AEXC_MASK (0x1fUL << FSR_AEXC_SHIFT)
- #define FSR_CEXC_SHIFT 0UL
- #define FSR_CEXC_MASK (0x1fUL << FSR_CEXC_SHIFT)
- /* All routines returning an exception to raise should detect
- * such exceptions _before_ rounding to be consistant with
- * the behavior of the hardware in the implemented cases
- * (and thus with the recommendations in the V9 architecture
- * manual).
- *
- * We return 0 if a SIGFPE should be sent, 1 otherwise.
- */
- static inline int record_exception(struct pt_regs *regs, int eflag)
- {
- u64 fsr = current->thread.xfsr[0];
- int would_trap;
- /* Determine if this exception would have generated a trap. */
- would_trap = (fsr & ((long)eflag << FSR_TEM_SHIFT)) != 0UL;
- /* If trapping, we only want to signal one bit. */
- if(would_trap != 0) {
- eflag &= ((fsr & FSR_TEM_MASK) >> FSR_TEM_SHIFT);
- if((eflag & (eflag - 1)) != 0) {
- if(eflag & FP_EX_INVALID)
- eflag = FP_EX_INVALID;
- else if(eflag & FP_EX_OVERFLOW)
- eflag = FP_EX_OVERFLOW;
- else if(eflag & FP_EX_UNDERFLOW)
- eflag = FP_EX_UNDERFLOW;
- else if(eflag & FP_EX_DIVZERO)
- eflag = FP_EX_DIVZERO;
- else if(eflag & FP_EX_INEXACT)
- eflag = FP_EX_INEXACT;
- }
- }
- /* Set CEXC, here is the rule:
- *
- * In general all FPU ops will set one and only one
- * bit in the CEXC field, this is always the case
- * when the IEEE exception trap is enabled in TEM.
- */
- fsr &= ~(FSR_CEXC_MASK);
- fsr |= ((long)eflag << FSR_CEXC_SHIFT);
- /* Set the AEXC field, rule is:
- *
- * If a trap would not be generated, the
- * CEXC just generated is OR'd into the
- * existing value of AEXC.
- */
- if(would_trap == 0)
- fsr |= ((long)eflag << FSR_AEXC_SHIFT);
- /* If trapping, indicate fault trap type IEEE. */
- if(would_trap != 0)
- fsr |= (1UL << 14);
- current->thread.xfsr[0] = fsr;
- /* If we will not trap, advance the program counter over
- * the instruction being handled.
- */
- if(would_trap == 0) {
- regs->tpc = regs->tnpc;
- regs->tnpc += 4;
- }
- return (would_trap ? 0 : 1);
- }
- typedef union {
- u32 s;
- u64 d;
- u64 q[2];
- } *argp;
- int do_mathemu(struct pt_regs *regs, struct fpustate *f)
- {
- unsigned long pc = regs->tpc;
- unsigned long tstate = regs->tstate;
- u32 insn = 0;
- int type = 0;
- /* ftt tells which ftt it may happen in, r is rd, b is rs2 and a is rs1. The *u arg tells
- whether the argument should be packed/unpacked (0 - do not unpack/pack, 1 - unpack/pack)
- non-u args tells the size of the argument (0 - no argument, 1 - single, 2 - double, 3 - quad */
- #define TYPE(ftt, r, ru, b, bu, a, au) type = (au << 2) | (a << 0) | (bu << 5) | (b << 3) | (ru << 8) | (r << 6) | (ftt << 9)
- int freg;
- static u64 zero[2] = { 0L, 0L };
- int flags;
- FP_DECL_EX;
- FP_DECL_S(SA); FP_DECL_S(SB); FP_DECL_S(SR);
- FP_DECL_D(DA); FP_DECL_D(DB); FP_DECL_D(DR);
- FP_DECL_Q(QA); FP_DECL_Q(QB); FP_DECL_Q(QR);
- int IR;
- long XR, xfsr;
- if(tstate & TSTATE_PRIV)
- die_if_kernel("FPQuad from kernel", regs);
- if(current->thread.flags & SPARC_FLAG_32BIT)
- pc = (u32)pc;
- if (get_user(insn, (u32 *)pc) != -EFAULT) {
- if ((insn & 0xc1f80000) == 0x81a00000) /* FPOP1 */ {
- switch ((insn >> 5) & 0x1ff) {
- /* QUAD - ftt == 3 */
- case FMOVQ:
- case FNEGQ:
- case FABSQ: TYPE(3,3,0,3,0,0,0); break;
- case FSQRTQ: TYPE(3,3,1,3,1,0,0); break;
- case FADDQ:
- case FSUBQ:
- case FMULQ:
- case FDIVQ: TYPE(3,3,1,3,1,3,1); break;
- case FDMULQ: TYPE(3,3,1,2,1,2,1); break;
- case FQTOX: TYPE(3,2,0,3,1,0,0); break;
- case FXTOQ: TYPE(3,3,1,2,0,0,0); break;
- case FQTOS: TYPE(3,1,1,3,1,0,0); break;
- case FQTOD: TYPE(3,2,1,3,1,0,0); break;
- case FITOQ: TYPE(3,3,1,1,0,0,0); break;
- case FSTOQ: TYPE(3,3,1,1,1,0,0); break;
- case FDTOQ: TYPE(3,3,1,2,1,0,0); break;
- case FQTOI: TYPE(3,1,0,3,1,0,0); break;
- /* SUBNORMAL - ftt == 2 */
- case FSQRTS: TYPE(2,1,1,1,1,0,0); break;
- case FSQRTD: TYPE(2,2,1,2,1,0,0); break;
- case FADDD:
- case FSUBD:
- case FMULD:
- case FDIVD: TYPE(2,2,1,2,1,2,1); break;
- case FADDS:
- case FSUBS:
- case FMULS:
- case FDIVS: TYPE(2,1,1,1,1,1,1); break;
- case FSMULD: TYPE(2,2,1,1,1,1,1); break;
- case FSTOX: TYPE(2,2,0,1,1,0,0); break;
- case FDTOX: TYPE(2,2,0,2,1,0,0); break;
- case FDTOS: TYPE(2,1,1,2,1,0,0); break;
- case FSTOD: TYPE(2,2,1,1,1,0,0); break;
- case FSTOI: TYPE(2,1,0,1,1,0,0); break;
- case FDTOI: TYPE(2,1,0,2,1,0,0); break;
- }
- }
- else if ((insn & 0xc1f80000) == 0x81a80000) /* FPOP2 */ {
- IR = 2;
- switch ((insn >> 5) & 0x1ff) {
- case FCMPQ: TYPE(3,0,0,3,1,3,1); break;
- case FCMPEQ: TYPE(3,0,0,3,1,3,1); break;
- /* Now the conditional fmovq support */
- case FMOVQ0:
- case FMOVQ1:
- case FMOVQ2:
- case FMOVQ3:
- /* fmovq %fccX, %fY, %fZ */
- if (!((insn >> 11) & 3))
- XR = current->thread.xfsr[0] >> 10;
- else
- XR = current->thread.xfsr[0] >> (30 + ((insn >> 10) & 0x6));
- XR &= 3;
- IR = 0;
- switch ((insn >> 14) & 0x7) {
- /* case 0: IR = 0; break; */ /* Never */
- case 1: if (XR) IR = 1; break; /* Not Equal */
- case 2: if (XR == 1 || XR == 2) IR = 1; break; /* Less or Greater */
- case 3: if (XR & 1) IR = 1; break; /* Unordered or Less */
- case 4: if (XR == 1) IR = 1; break; /* Less */
- case 5: if (XR & 2) IR = 1; break; /* Unordered or Greater */
- case 6: if (XR == 2) IR = 1; break; /* Greater */
- case 7: if (XR == 3) IR = 1; break; /* Unordered */
- }
- if ((insn >> 14) & 8)
- IR ^= 1;
- break;
- case FMOVQI:
- case FMOVQX:
- /* fmovq %[ix]cc, %fY, %fZ */
- XR = regs->tstate >> 32;
- if ((insn >> 5) & 0x80)
- XR >>= 4;
- XR &= 0xf;
- IR = 0;
- freg = ((XR >> 2) ^ XR) & 2;
- switch ((insn >> 14) & 0x7) {
- /* case 0: IR = 0; break; */ /* Never */
- case 1: if (XR & 4) IR = 1; break; /* Equal */
- case 2: if ((XR & 4) || freg) IR = 1; break; /* Less or Equal */
- case 3: if (freg) IR = 1; break; /* Less */
- case 4: if (XR & 5) IR = 1; break; /* Less or Equal Unsigned */
- case 5: if (XR & 1) IR = 1; break; /* Carry Set */
- case 6: if (XR & 8) IR = 1; break; /* Negative */
- case 7: if (XR & 2) IR = 1; break; /* Overflow Set */
- }
- if ((insn >> 14) & 8)
- IR ^= 1;
- break;
- case FMOVQZ:
- case FMOVQLE:
- case FMOVQLZ:
- case FMOVQNZ:
- case FMOVQGZ:
- case FMOVQGE:
- freg = (insn >> 14) & 0x1f;
- if (!freg)
- XR = 0;
- else if (freg < 16)
- XR = regs->u_regs[freg];
- else if (current->thread.flags & SPARC_FLAG_32BIT) {
- struct reg_window32 *win32;
- flushw_user ();
- win32 = (struct reg_window32 *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
- get_user(XR, &win32->locals[freg - 16]);
- } else {
- struct reg_window *win;
- flushw_user ();
- win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
- get_user(XR, &win->locals[freg - 16]);
- }
- IR = 0;
- switch ((insn >> 10) & 3) {
- case 1: if (!XR) IR = 1; break; /* Register Zero */
- case 2: if (XR <= 0) IR = 1; break; /* Register Less Than or Equal to Zero */
- case 3: if (XR < 0) IR = 1; break; /* Register Less Than Zero */
- }
- if ((insn >> 10) & 4)
- IR ^= 1;
- break;
- }
- if (IR == 0) {
- /* The fmov test was false. Do a nop instead */
- current->thread.xfsr[0] &= ~(FSR_CEXC_MASK);
- regs->tpc = regs->tnpc;
- regs->tnpc += 4;
- return 1;
- } else if (IR == 1) {
- /* Change the instruction into plain fmovq */
- insn = (insn & 0x3e00001f) | 0x81a00060;
- TYPE(3,3,0,3,0,0,0);
- }
- }
- }
- if (type) {
- argp rs1 = NULL, rs2 = NULL, rd = NULL;
-
- freg = (current->thread.xfsr[0] >> 14) & 0xf;
- if (freg != (type >> 9))
- goto err;
- current->thread.xfsr[0] &= ~0x1c000;
- freg = ((insn >> 14) & 0x1f);
- switch (type & 0x3) {
- case 3: if (freg & 2) {
- current->thread.xfsr[0] |= (6 << 14) /* invalid_fp_register */;
- goto err;
- }
- case 2: freg = ((freg & 1) << 5) | (freg & 0x1e);
- case 1: rs1 = (argp)&f->regs[freg];
- flags = (freg < 32) ? FPRS_DL : FPRS_DU;
- if (!(current->thread.fpsaved[0] & flags))
- rs1 = (argp)&zero;
- break;
- }
- switch (type & 0x7) {
- case 7: FP_UNPACK_QP (QA, rs1); break;
- case 6: FP_UNPACK_DP (DA, rs1); break;
- case 5: FP_UNPACK_SP (SA, rs1); break;
- }
- freg = (insn & 0x1f);
- switch ((type >> 3) & 0x3) {
- case 3: if (freg & 2) {
- current->thread.xfsr[0] |= (6 << 14) /* invalid_fp_register */;
- goto err;
- }
- case 2: freg = ((freg & 1) << 5) | (freg & 0x1e);
- case 1: rs2 = (argp)&f->regs[freg];
- flags = (freg < 32) ? FPRS_DL : FPRS_DU;
- if (!(current->thread.fpsaved[0] & flags))
- rs2 = (argp)&zero;
- break;
- }
- switch ((type >> 3) & 0x7) {
- case 7: FP_UNPACK_QP (QB, rs2); break;
- case 6: FP_UNPACK_DP (DB, rs2); break;
- case 5: FP_UNPACK_SP (SB, rs2); break;
- }
- freg = ((insn >> 25) & 0x1f);
- switch ((type >> 6) & 0x3) {
- case 3: if (freg & 2) {
- current->thread.xfsr[0] |= (6 << 14) /* invalid_fp_register */;
- goto err;
- }
- case 2: freg = ((freg & 1) << 5) | (freg & 0x1e);
- case 1: rd = (argp)&f->regs[freg];
- flags = (freg < 32) ? FPRS_DL : FPRS_DU;
- if (!(current->thread.fpsaved[0] & FPRS_FEF)) {
- current->thread.fpsaved[0] = FPRS_FEF;
- current->thread.gsr[0] = 0;
- }
- if (!(current->thread.fpsaved[0] & flags)) {
- if (freg < 32)
- memset(f->regs, 0, 32*sizeof(u32));
- else
- memset(f->regs+32, 0, 32*sizeof(u32));
- }
- current->thread.fpsaved[0] |= flags;
- break;
- }
- switch ((insn >> 5) & 0x1ff) {
- /* + */
- case FADDS: FP_ADD_S (SR, SA, SB); break;
- case FADDD: FP_ADD_D (DR, DA, DB); break;
- case FADDQ: FP_ADD_Q (QR, QA, QB); break;
- /* - */
- case FSUBS: FP_SUB_S (SR, SA, SB); break;
- case FSUBD: FP_SUB_D (DR, DA, DB); break;
- case FSUBQ: FP_SUB_Q (QR, QA, QB); break;
- /* * */
- case FMULS: FP_MUL_S (SR, SA, SB); break;
- case FSMULD: FP_CONV (D, S, 1, 1, DA, SA);
- FP_CONV (D, S, 1, 1, DB, SB);
- case FMULD: FP_MUL_D (DR, DA, DB); break;
- case FDMULQ: FP_CONV (Q, D, 2, 1, QA, DA);
- FP_CONV (Q, D, 2, 1, QB, DB);
- case FMULQ: FP_MUL_Q (QR, QA, QB); break;
- /* / */
- case FDIVS: FP_DIV_S (SR, SA, SB); break;
- case FDIVD: FP_DIV_D (DR, DA, DB); break;
- case FDIVQ: FP_DIV_Q (QR, QA, QB); break;
- /* sqrt */
- case FSQRTS: FP_SQRT_S (SR, SB); break;
- case FSQRTD: FP_SQRT_D (DR, DB); break;
- case FSQRTQ: FP_SQRT_Q (QR, QB); break;
- /* mov */
- case FMOVQ: rd->q[0] = rs2->q[0]; rd->q[1] = rs2->q[1]; break;
- case FABSQ: rd->q[0] = rs2->q[0] & 0x7fffffffffffffffUL; rd->q[1] = rs2->q[1]; break;
- case FNEGQ: rd->q[0] = rs2->q[0] ^ 0x8000000000000000UL; rd->q[1] = rs2->q[1]; break;
- /* float to int */
- case FSTOI: FP_TO_INT_S (IR, SB, 32, 1); break;
- case FDTOI: FP_TO_INT_D (IR, DB, 32, 1); break;
- case FQTOI: FP_TO_INT_Q (IR, QB, 32, 1); break;
- case FSTOX: FP_TO_INT_S (XR, SB, 64, 1); break;
- case FDTOX: FP_TO_INT_D (XR, DB, 64, 1); break;
- case FQTOX: FP_TO_INT_Q (XR, QB, 64, 1); break;
- /* int to float */
- case FITOQ: IR = rs2->s; FP_FROM_INT_Q (QR, IR, 32, int); break;
- case FXTOQ: XR = rs2->d; FP_FROM_INT_Q (QR, XR, 64, long); break;
- /* float to float */
- case FSTOD: FP_CONV (D, S, 1, 1, DR, SB); break;
- case FSTOQ: FP_CONV (Q, S, 2, 1, QR, SB); break;
- case FDTOQ: FP_CONV (Q, D, 2, 1, QR, DB); break;
- case FDTOS: FP_CONV (S, D, 1, 1, SR, DB); break;
- case FQTOS: FP_CONV (S, Q, 1, 2, SR, QB); break;
- case FQTOD: FP_CONV (D, Q, 1, 2, DR, QB); break;
- /* comparison */
- case FCMPQ:
- case FCMPEQ:
- FP_CMP_Q(XR, QB, QA, 3);
- if (XR == 3 &&
- (((insn >> 5) & 0x1ff) == FCMPEQ ||
- FP_ISSIGNAN_Q(QA) ||
- FP_ISSIGNAN_Q(QB)))
- FP_SET_EXCEPTION (FP_EX_INVALID);
- }
- if (!FP_INHIBIT_RESULTS) {
- switch ((type >> 6) & 0x7) {
- case 0: xfsr = current->thread.xfsr[0];
- if (XR == -1) XR = 2;
- switch (freg & 3) {
- /* fcc0, 1, 2, 3 */
- case 0: xfsr &= ~0xc00; xfsr |= (XR << 10); break;
- case 1: xfsr &= ~0x300000000UL; xfsr |= (XR << 32); break;
- case 2: xfsr &= ~0xc00000000UL; xfsr |= (XR << 34); break;
- case 3: xfsr &= ~0x3000000000UL; xfsr |= (XR << 36); break;
- }
- current->thread.xfsr[0] = xfsr;
- break;
- case 1: rd->s = IR; break;
- case 2: rd->d = XR; break;
- case 5: FP_PACK_SP (rd, SR); break;
- case 6: FP_PACK_DP (rd, DR); break;
- case 7: FP_PACK_QP (rd, QR); break;
- }
- }
- if(_fex != 0)
- return record_exception(regs, _fex);
- /* Success and no exceptions detected. */
- current->thread.xfsr[0] &= ~(FSR_CEXC_MASK);
- regs->tpc = regs->tnpc;
- regs->tnpc += 4;
- return 1;
- }
- err: return 0;
- }