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-rw-r--r--arch/sparc/math-emu/math_64.c525
1 files changed, 525 insertions, 0 deletions
diff --git a/arch/sparc/math-emu/math_64.c b/arch/sparc/math-emu/math_64.c
new file mode 100644
index 000000000..1379dee26
--- /dev/null
+++ b/arch/sparc/math-emu/math_64.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 <linux/errno.h>
+#include <linux/perf_event.h>
+
+#include <asm/fpumacro.h>
+#include <asm/ptrace.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+
+#include "sfp-util_64.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
+#define FXTOS 0x084 /* Only Ultra-III generates this. */
+#define FXTOD 0x088 /* Only Ultra-III generates this. */
+#if 0 /* Optimized inline in sparc64/kernel/entry.S */
+#define FITOS 0x0c4 /* Only Ultra-III generates this. */
+#endif
+#define FITOD 0x0c8 /* Only Ultra-III generates this. */
+/* 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 consistent 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_info()->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_info()->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, bool illegal_insn_trap)
+{
+ 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("unfinished/unimplemented FPop from kernel", regs);
+ perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
+ if (test_thread_flag(TIF_32BIT))
+ pc = (u32)pc;
+ if (get_user(insn, (u32 __user *) 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;
+
+ /* We can get either unimplemented or unfinished
+ * for these cases. Pre-Niagara systems generate
+ * unfinished fpop for SUBNORMAL cases, and Niagara
+ * always gives unimplemented fpop for fsqrt{s,d}.
+ */
+ case FSQRTS: {
+ unsigned long x = current_thread_info()->xfsr[0];
+
+ x = (x >> 14) & 0x7;
+ TYPE(x,1,1,1,1,0,0);
+ break;
+ }
+
+ case FSQRTD: {
+ unsigned long x = current_thread_info()->xfsr[0];
+
+ x = (x >> 14) & 0x7;
+ TYPE(x,2,1,2,1,0,0);
+ break;
+ }
+
+ /* SUBNORMAL - ftt == 2 */
+ 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;
+
+ /* Only Ultra-III generates these */
+ case FXTOS: TYPE(2,1,1,2,0,0,0); break;
+ case FXTOD: TYPE(2,2,1,2,0,0,0); break;
+#if 0 /* Optimized inline in sparc64/kernel/entry.S */
+ case FITOS: TYPE(2,1,1,1,0,0,0); break;
+#endif
+ case FITOD: TYPE(2,2,1,1,0,0,0); 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_info()->xfsr[0] >> 10;
+ else
+ XR = current_thread_info()->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 (!test_thread_64bit_stack(regs->u_regs[UREG_FP])) {
+ struct reg_window32 __user *win32;
+ flushw_user ();
+ win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
+ get_user(XR, &win32->locals[freg - 16]);
+ } else {
+ struct reg_window __user *win;
+ flushw_user ();
+ win = (struct reg_window __user *)(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_info()->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;
+
+ /* Starting with UltraSPARC-T2, the cpu does not set the FP Trap
+ * Type field in the %fsr to unimplemented_FPop. Nor does it
+ * use the fp_exception_other trap. Instead it signals an
+ * illegal instruction and leaves the FP trap type field of
+ * the %fsr unchanged.
+ */
+ if (!illegal_insn_trap) {
+ int ftt = (current_thread_info()->xfsr[0] >> 14) & 0x7;
+ if (ftt != (type >> 9))
+ goto err;
+ }
+ current_thread_info()->xfsr[0] &= ~0x1c000;
+ freg = ((insn >> 14) & 0x1f);
+ switch (type & 0x3) {
+ case 3: if (freg & 2) {
+ current_thread_info()->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_info()->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_info()->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_info()->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_info()->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_info()->fpsaved[0] & FPRS_FEF)) {
+ current_thread_info()->fpsaved[0] = FPRS_FEF;
+ current_thread_info()->gsr[0] = 0;
+ }
+ if (!(current_thread_info()->fpsaved[0] & flags)) {
+ if (freg < 32)
+ memset(f->regs, 0, 32*sizeof(u32));
+ else
+ memset(f->regs+32, 0, 32*sizeof(u32));
+ }
+ current_thread_info()->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;
+ /* Only Ultra-III generates these */
+ case FXTOS: XR = rs2->d; FP_FROM_INT_S (SR, XR, 64, long); break;
+ case FXTOD: XR = rs2->d; FP_FROM_INT_D (DR, XR, 64, long); break;
+#if 0 /* Optimized inline in sparc64/kernel/entry.S */
+ case FITOS: IR = rs2->s; FP_FROM_INT_S (SR, IR, 32, int); break;
+#endif
+ case FITOD: IR = rs2->s; FP_FROM_INT_D (DR, IR, 32, int); 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_info()->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_info()->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_info()->xfsr[0] &= ~(FSR_CEXC_MASK);
+ regs->tpc = regs->tnpc;
+ regs->tnpc += 4;
+ return 1;
+ }
+err: return 0;
+}