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-rw-r--r--arch/arm/vfp/vfpsingle.c1224
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diff --git a/arch/arm/vfp/vfpsingle.c b/arch/arm/vfp/vfpsingle.c
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+++ b/arch/arm/vfp/vfpsingle.c
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+/*
+ * linux/arch/arm/vfp/vfpsingle.c
+ *
+ * This code is derived in part from John R. Housers softfloat library, which
+ * carries the following notice:
+ *
+ * ===========================================================================
+ * This C source file is part of the SoftFloat IEC/IEEE Floating-point
+ * Arithmetic Package, Release 2.
+ *
+ * Written by John R. Hauser. This work was made possible in part by the
+ * International Computer Science Institute, located at Suite 600, 1947 Center
+ * Street, Berkeley, California 94704. Funding was partially provided by the
+ * National Science Foundation under grant MIP-9311980. The original version
+ * of this code was written as part of a project to build a fixed-point vector
+ * processor in collaboration with the University of California at Berkeley,
+ * overseen by Profs. Nelson Morgan and John Wawrzynek. More information
+ * is available through the web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
+ * arithmetic/softfloat.html'.
+ *
+ * THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
+ * has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
+ * TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
+ * PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
+ * AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
+ *
+ * Derivative works are acceptable, even for commercial purposes, so long as
+ * (1) they include prominent notice that the work is derivative, and (2) they
+ * include prominent notice akin to these three paragraphs for those parts of
+ * this code that are retained.
+ * ===========================================================================
+ */
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <asm/ptrace.h>
+#include <asm/vfp.h>
+
+#include "vfpinstr.h"
+#include "vfp.h"
+
+static struct vfp_single vfp_single_default_qnan = {
+ .exponent = 255,
+ .sign = 0,
+ .significand = VFP_SINGLE_SIGNIFICAND_QNAN,
+};
+
+static void vfp_single_dump(const char *str, struct vfp_single *s)
+{
+ pr_debug("VFP: %s: sign=%d exponent=%d significand=%08x\n",
+ str, s->sign != 0, s->exponent, s->significand);
+}
+
+static void vfp_single_normalise_denormal(struct vfp_single *vs)
+{
+ int bits = 31 - fls(vs->significand);
+
+ vfp_single_dump("normalise_denormal: in", vs);
+
+ if (bits) {
+ vs->exponent -= bits - 1;
+ vs->significand <<= bits;
+ }
+
+ vfp_single_dump("normalise_denormal: out", vs);
+}
+
+#ifndef DEBUG
+#define vfp_single_normaliseround(sd,vsd,fpscr,except,func) __vfp_single_normaliseround(sd,vsd,fpscr,except)
+u32 __vfp_single_normaliseround(int sd, struct vfp_single *vs, u32 fpscr, u32 exceptions)
+#else
+u32 vfp_single_normaliseround(int sd, struct vfp_single *vs, u32 fpscr, u32 exceptions, const char *func)
+#endif
+{
+ u32 significand, incr, rmode;
+ int exponent, shift, underflow;
+
+ vfp_single_dump("pack: in", vs);
+
+ /*
+ * Infinities and NaNs are a special case.
+ */
+ if (vs->exponent == 255 && (vs->significand == 0 || exceptions))
+ goto pack;
+
+ /*
+ * Special-case zero.
+ */
+ if (vs->significand == 0) {
+ vs->exponent = 0;
+ goto pack;
+ }
+
+ exponent = vs->exponent;
+ significand = vs->significand;
+
+ /*
+ * Normalise first. Note that we shift the significand up to
+ * bit 31, so we have VFP_SINGLE_LOW_BITS + 1 below the least
+ * significant bit.
+ */
+ shift = 32 - fls(significand);
+ if (shift < 32 && shift) {
+ exponent -= shift;
+ significand <<= shift;
+ }
+
+#ifdef DEBUG
+ vs->exponent = exponent;
+ vs->significand = significand;
+ vfp_single_dump("pack: normalised", vs);
+#endif
+
+ /*
+ * Tiny number?
+ */
+ underflow = exponent < 0;
+ if (underflow) {
+ significand = vfp_shiftright32jamming(significand, -exponent);
+ exponent = 0;
+#ifdef DEBUG
+ vs->exponent = exponent;
+ vs->significand = significand;
+ vfp_single_dump("pack: tiny number", vs);
+#endif
+ if (!(significand & ((1 << (VFP_SINGLE_LOW_BITS + 1)) - 1)))
+ underflow = 0;
+ }
+
+ /*
+ * Select rounding increment.
+ */
+ incr = 0;
+ rmode = fpscr & FPSCR_RMODE_MASK;
+
+ if (rmode == FPSCR_ROUND_NEAREST) {
+ incr = 1 << VFP_SINGLE_LOW_BITS;
+ if ((significand & (1 << (VFP_SINGLE_LOW_BITS + 1))) == 0)
+ incr -= 1;
+ } else if (rmode == FPSCR_ROUND_TOZERO) {
+ incr = 0;
+ } else if ((rmode == FPSCR_ROUND_PLUSINF) ^ (vs->sign != 0))
+ incr = (1 << (VFP_SINGLE_LOW_BITS + 1)) - 1;
+
+ pr_debug("VFP: rounding increment = 0x%08x\n", incr);
+
+ /*
+ * Is our rounding going to overflow?
+ */
+ if ((significand + incr) < significand) {
+ exponent += 1;
+ significand = (significand >> 1) | (significand & 1);
+ incr >>= 1;
+#ifdef DEBUG
+ vs->exponent = exponent;
+ vs->significand = significand;
+ vfp_single_dump("pack: overflow", vs);
+#endif
+ }
+
+ /*
+ * If any of the low bits (which will be shifted out of the
+ * number) are non-zero, the result is inexact.
+ */
+ if (significand & ((1 << (VFP_SINGLE_LOW_BITS + 1)) - 1))
+ exceptions |= FPSCR_IXC;
+
+ /*
+ * Do our rounding.
+ */
+ significand += incr;
+
+ /*
+ * Infinity?
+ */
+ if (exponent >= 254) {
+ exceptions |= FPSCR_OFC | FPSCR_IXC;
+ if (incr == 0) {
+ vs->exponent = 253;
+ vs->significand = 0x7fffffff;
+ } else {
+ vs->exponent = 255; /* infinity */
+ vs->significand = 0;
+ }
+ } else {
+ if (significand >> (VFP_SINGLE_LOW_BITS + 1) == 0)
+ exponent = 0;
+ if (exponent || significand > 0x80000000)
+ underflow = 0;
+ if (underflow)
+ exceptions |= FPSCR_UFC;
+ vs->exponent = exponent;
+ vs->significand = significand >> 1;
+ }
+
+ pack:
+ vfp_single_dump("pack: final", vs);
+ {
+ s32 d = vfp_single_pack(vs);
+ pr_debug("VFP: %s: d(s%d)=%08x exceptions=%08x\n", func,
+ sd, d, exceptions);
+ vfp_put_float(sd, d);
+ }
+
+ return exceptions & ~VFP_NAN_FLAG;
+}
+
+/*
+ * Propagate the NaN, setting exceptions if it is signalling.
+ * 'n' is always a NaN. 'm' may be a number, NaN or infinity.
+ */
+static u32
+vfp_propagate_nan(struct vfp_single *vsd, struct vfp_single *vsn,
+ struct vfp_single *vsm, u32 fpscr)
+{
+ struct vfp_single *nan;
+ int tn, tm = 0;
+
+ tn = vfp_single_type(vsn);
+
+ if (vsm)
+ tm = vfp_single_type(vsm);
+
+ if (fpscr & FPSCR_DEFAULT_NAN)
+ /*
+ * Default NaN mode - always returns a quiet NaN
+ */
+ nan = &vfp_single_default_qnan;
+ else {
+ /*
+ * Contemporary mode - select the first signalling
+ * NAN, or if neither are signalling, the first
+ * quiet NAN.
+ */
+ if (tn == VFP_SNAN || (tm != VFP_SNAN && tn == VFP_QNAN))
+ nan = vsn;
+ else
+ nan = vsm;
+ /*
+ * Make the NaN quiet.
+ */
+ nan->significand |= VFP_SINGLE_SIGNIFICAND_QNAN;
+ }
+
+ *vsd = *nan;
+
+ /*
+ * If one was a signalling NAN, raise invalid operation.
+ */
+ return tn == VFP_SNAN || tm == VFP_SNAN ? FPSCR_IOC : VFP_NAN_FLAG;
+}
+
+
+/*
+ * Extended operations
+ */
+static u32 vfp_single_fabs(int sd, int unused, s32 m, u32 fpscr)
+{
+ vfp_put_float(sd, vfp_single_packed_abs(m));
+ return 0;
+}
+
+static u32 vfp_single_fcpy(int sd, int unused, s32 m, u32 fpscr)
+{
+ vfp_put_float(sd, m);
+ return 0;
+}
+
+static u32 vfp_single_fneg(int sd, int unused, s32 m, u32 fpscr)
+{
+ vfp_put_float(sd, vfp_single_packed_negate(m));
+ return 0;
+}
+
+static const u16 sqrt_oddadjust[] = {
+ 0x0004, 0x0022, 0x005d, 0x00b1, 0x011d, 0x019f, 0x0236, 0x02e0,
+ 0x039c, 0x0468, 0x0545, 0x0631, 0x072b, 0x0832, 0x0946, 0x0a67
+};
+
+static const u16 sqrt_evenadjust[] = {
+ 0x0a2d, 0x08af, 0x075a, 0x0629, 0x051a, 0x0429, 0x0356, 0x029e,
+ 0x0200, 0x0179, 0x0109, 0x00af, 0x0068, 0x0034, 0x0012, 0x0002
+};
+
+u32 vfp_estimate_sqrt_significand(u32 exponent, u32 significand)
+{
+ int index;
+ u32 z, a;
+
+ if ((significand & 0xc0000000) != 0x40000000) {
+ printk(KERN_WARNING "VFP: estimate_sqrt: invalid significand\n");
+ }
+
+ a = significand << 1;
+ index = (a >> 27) & 15;
+ if (exponent & 1) {
+ z = 0x4000 + (a >> 17) - sqrt_oddadjust[index];
+ z = ((a / z) << 14) + (z << 15);
+ a >>= 1;
+ } else {
+ z = 0x8000 + (a >> 17) - sqrt_evenadjust[index];
+ z = a / z + z;
+ z = (z >= 0x20000) ? 0xffff8000 : (z << 15);
+ if (z <= a)
+ return (s32)a >> 1;
+ }
+ return (u32)(((u64)a << 31) / z) + (z >> 1);
+}
+
+static u32 vfp_single_fsqrt(int sd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vsm, vsd;
+ int ret, tm;
+
+ vfp_single_unpack(&vsm, m);
+ tm = vfp_single_type(&vsm);
+ if (tm & (VFP_NAN|VFP_INFINITY)) {
+ struct vfp_single *vsp = &vsd;
+
+ if (tm & VFP_NAN)
+ ret = vfp_propagate_nan(vsp, &vsm, NULL, fpscr);
+ else if (vsm.sign == 0) {
+ sqrt_copy:
+ vsp = &vsm;
+ ret = 0;
+ } else {
+ sqrt_invalid:
+ vsp = &vfp_single_default_qnan;
+ ret = FPSCR_IOC;
+ }
+ vfp_put_float(sd, vfp_single_pack(vsp));
+ return ret;
+ }
+
+ /*
+ * sqrt(+/- 0) == +/- 0
+ */
+ if (tm & VFP_ZERO)
+ goto sqrt_copy;
+
+ /*
+ * Normalise a denormalised number
+ */
+ if (tm & VFP_DENORMAL)
+ vfp_single_normalise_denormal(&vsm);
+
+ /*
+ * sqrt(<0) = invalid
+ */
+ if (vsm.sign)
+ goto sqrt_invalid;
+
+ vfp_single_dump("sqrt", &vsm);
+
+ /*
+ * Estimate the square root.
+ */
+ vsd.sign = 0;
+ vsd.exponent = ((vsm.exponent - 127) >> 1) + 127;
+ vsd.significand = vfp_estimate_sqrt_significand(vsm.exponent, vsm.significand) + 2;
+
+ vfp_single_dump("sqrt estimate", &vsd);
+
+ /*
+ * And now adjust.
+ */
+ if ((vsd.significand & VFP_SINGLE_LOW_BITS_MASK) <= 5) {
+ if (vsd.significand < 2) {
+ vsd.significand = 0xffffffff;
+ } else {
+ u64 term;
+ s64 rem;
+ vsm.significand <<= !(vsm.exponent & 1);
+ term = (u64)vsd.significand * vsd.significand;
+ rem = ((u64)vsm.significand << 32) - term;
+
+ pr_debug("VFP: term=%016llx rem=%016llx\n", term, rem);
+
+ while (rem < 0) {
+ vsd.significand -= 1;
+ rem += ((u64)vsd.significand << 1) | 1;
+ }
+ vsd.significand |= rem != 0;
+ }
+ }
+ vsd.significand = vfp_shiftright32jamming(vsd.significand, 1);
+
+ return vfp_single_normaliseround(sd, &vsd, fpscr, 0, "fsqrt");
+}
+
+/*
+ * Equal := ZC
+ * Less than := N
+ * Greater than := C
+ * Unordered := CV
+ */
+static u32 vfp_compare(int sd, int signal_on_qnan, s32 m, u32 fpscr)
+{
+ s32 d;
+ u32 ret = 0;
+
+ d = vfp_get_float(sd);
+ if (vfp_single_packed_exponent(m) == 255 && vfp_single_packed_mantissa(m)) {
+ ret |= FPSCR_C | FPSCR_V;
+ if (signal_on_qnan || !(vfp_single_packed_mantissa(m) & (1 << (VFP_SINGLE_MANTISSA_BITS - 1))))
+ /*
+ * Signalling NaN, or signalling on quiet NaN
+ */
+ ret |= FPSCR_IOC;
+ }
+
+ if (vfp_single_packed_exponent(d) == 255 && vfp_single_packed_mantissa(d)) {
+ ret |= FPSCR_C | FPSCR_V;
+ if (signal_on_qnan || !(vfp_single_packed_mantissa(d) & (1 << (VFP_SINGLE_MANTISSA_BITS - 1))))
+ /*
+ * Signalling NaN, or signalling on quiet NaN
+ */
+ ret |= FPSCR_IOC;
+ }
+
+ if (ret == 0) {
+ if (d == m || vfp_single_packed_abs(d | m) == 0) {
+ /*
+ * equal
+ */
+ ret |= FPSCR_Z | FPSCR_C;
+ } else if (vfp_single_packed_sign(d ^ m)) {
+ /*
+ * different signs
+ */
+ if (vfp_single_packed_sign(d))
+ /*
+ * d is negative, so d < m
+ */
+ ret |= FPSCR_N;
+ else
+ /*
+ * d is positive, so d > m
+ */
+ ret |= FPSCR_C;
+ } else if ((vfp_single_packed_sign(d) != 0) ^ (d < m)) {
+ /*
+ * d < m
+ */
+ ret |= FPSCR_N;
+ } else if ((vfp_single_packed_sign(d) != 0) ^ (d > m)) {
+ /*
+ * d > m
+ */
+ ret |= FPSCR_C;
+ }
+ }
+ return ret;
+}
+
+static u32 vfp_single_fcmp(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_compare(sd, 0, m, fpscr);
+}
+
+static u32 vfp_single_fcmpe(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_compare(sd, 1, m, fpscr);
+}
+
+static u32 vfp_single_fcmpz(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_compare(sd, 0, 0, fpscr);
+}
+
+static u32 vfp_single_fcmpez(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_compare(sd, 1, 0, fpscr);
+}
+
+static u32 vfp_single_fcvtd(int dd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vsm;
+ struct vfp_double vdd;
+ int tm;
+ u32 exceptions = 0;
+
+ vfp_single_unpack(&vsm, m);
+
+ tm = vfp_single_type(&vsm);
+
+ /*
+ * If we have a signalling NaN, signal invalid operation.
+ */
+ if (tm == VFP_SNAN)
+ exceptions = FPSCR_IOC;
+
+ if (tm & VFP_DENORMAL)
+ vfp_single_normalise_denormal(&vsm);
+
+ vdd.sign = vsm.sign;
+ vdd.significand = (u64)vsm.significand << 32;
+
+ /*
+ * If we have an infinity or NaN, the exponent must be 2047.
+ */
+ if (tm & (VFP_INFINITY|VFP_NAN)) {
+ vdd.exponent = 2047;
+ if (tm & VFP_NAN)
+ vdd.significand |= VFP_DOUBLE_SIGNIFICAND_QNAN;
+ goto pack_nan;
+ } else if (tm & VFP_ZERO)
+ vdd.exponent = 0;
+ else
+ vdd.exponent = vsm.exponent + (1023 - 127);
+
+ /*
+ * Technically, if bit 0 of dd is set, this is an invalid
+ * instruction. However, we ignore this for efficiency.
+ */
+ return vfp_double_normaliseround(dd, &vdd, fpscr, exceptions, "fcvtd");
+
+ pack_nan:
+ vfp_put_double(dd, vfp_double_pack(&vdd));
+ return exceptions;
+}
+
+static u32 vfp_single_fuito(int sd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vs;
+
+ vs.sign = 0;
+ vs.exponent = 127 + 31 - 1;
+ vs.significand = (u32)m;
+
+ return vfp_single_normaliseround(sd, &vs, fpscr, 0, "fuito");
+}
+
+static u32 vfp_single_fsito(int sd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vs;
+
+ vs.sign = (m & 0x80000000) >> 16;
+ vs.exponent = 127 + 31 - 1;
+ vs.significand = vs.sign ? -m : m;
+
+ return vfp_single_normaliseround(sd, &vs, fpscr, 0, "fsito");
+}
+
+static u32 vfp_single_ftoui(int sd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vsm;
+ u32 d, exceptions = 0;
+ int rmode = fpscr & FPSCR_RMODE_MASK;
+ int tm;
+
+ vfp_single_unpack(&vsm, m);
+ vfp_single_dump("VSM", &vsm);
+
+ /*
+ * Do we have a denormalised number?
+ */
+ tm = vfp_single_type(&vsm);
+ if (tm & VFP_DENORMAL)
+ exceptions |= FPSCR_IDC;
+
+ if (tm & VFP_NAN)
+ vsm.sign = 0;
+
+ if (vsm.exponent >= 127 + 32) {
+ d = vsm.sign ? 0 : 0xffffffff;
+ exceptions = FPSCR_IOC;
+ } else if (vsm.exponent >= 127 - 1) {
+ int shift = 127 + 31 - vsm.exponent;
+ u32 rem, incr = 0;
+
+ /*
+ * 2^0 <= m < 2^32-2^8
+ */
+ d = (vsm.significand << 1) >> shift;
+ rem = vsm.significand << (33 - shift);
+
+ if (rmode == FPSCR_ROUND_NEAREST) {
+ incr = 0x80000000;
+ if ((d & 1) == 0)
+ incr -= 1;
+ } else if (rmode == FPSCR_ROUND_TOZERO) {
+ incr = 0;
+ } else if ((rmode == FPSCR_ROUND_PLUSINF) ^ (vsm.sign != 0)) {
+ incr = ~0;
+ }
+
+ if ((rem + incr) < rem) {
+ if (d < 0xffffffff)
+ d += 1;
+ else
+ exceptions |= FPSCR_IOC;
+ }
+
+ if (d && vsm.sign) {
+ d = 0;
+ exceptions |= FPSCR_IOC;
+ } else if (rem)
+ exceptions |= FPSCR_IXC;
+ } else {
+ d = 0;
+ if (vsm.exponent | vsm.significand) {
+ exceptions |= FPSCR_IXC;
+ if (rmode == FPSCR_ROUND_PLUSINF && vsm.sign == 0)
+ d = 1;
+ else if (rmode == FPSCR_ROUND_MINUSINF && vsm.sign) {
+ d = 0;
+ exceptions |= FPSCR_IOC;
+ }
+ }
+ }
+
+ pr_debug("VFP: ftoui: d(s%d)=%08x exceptions=%08x\n", sd, d, exceptions);
+
+ vfp_put_float(sd, d);
+
+ return exceptions;
+}
+
+static u32 vfp_single_ftouiz(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_single_ftoui(sd, unused, m, FPSCR_ROUND_TOZERO);
+}
+
+static u32 vfp_single_ftosi(int sd, int unused, s32 m, u32 fpscr)
+{
+ struct vfp_single vsm;
+ u32 d, exceptions = 0;
+ int rmode = fpscr & FPSCR_RMODE_MASK;
+
+ vfp_single_unpack(&vsm, m);
+ vfp_single_dump("VSM", &vsm);
+
+ /*
+ * Do we have a denormalised number?
+ */
+ if (vfp_single_type(&vsm) & VFP_DENORMAL)
+ exceptions |= FPSCR_IDC;
+
+ if (vsm.exponent >= 127 + 32) {
+ /*
+ * m >= 2^31-2^7: invalid
+ */
+ d = 0x7fffffff;
+ if (vsm.sign)
+ d = ~d;
+ exceptions |= FPSCR_IOC;
+ } else if (vsm.exponent >= 127 - 1) {
+ int shift = 127 + 31 - vsm.exponent;
+ u32 rem, incr = 0;
+
+ /* 2^0 <= m <= 2^31-2^7 */
+ d = (vsm.significand << 1) >> shift;
+ rem = vsm.significand << (33 - shift);
+
+ if (rmode == FPSCR_ROUND_NEAREST) {
+ incr = 0x80000000;
+ if ((d & 1) == 0)
+ incr -= 1;
+ } else if (rmode == FPSCR_ROUND_TOZERO) {
+ incr = 0;
+ } else if ((rmode == FPSCR_ROUND_PLUSINF) ^ (vsm.sign != 0)) {
+ incr = ~0;
+ }
+
+ if ((rem + incr) < rem && d < 0xffffffff)
+ d += 1;
+ if (d > 0x7fffffff + (vsm.sign != 0)) {
+ d = 0x7fffffff + (vsm.sign != 0);
+ exceptions |= FPSCR_IOC;
+ } else if (rem)
+ exceptions |= FPSCR_IXC;
+
+ if (vsm.sign)
+ d = -d;
+ } else {
+ d = 0;
+ if (vsm.exponent | vsm.significand) {
+ exceptions |= FPSCR_IXC;
+ if (rmode == FPSCR_ROUND_PLUSINF && vsm.sign == 0)
+ d = 1;
+ else if (rmode == FPSCR_ROUND_MINUSINF && vsm.sign)
+ d = -1;
+ }
+ }
+
+ pr_debug("VFP: ftosi: d(s%d)=%08x exceptions=%08x\n", sd, d, exceptions);
+
+ vfp_put_float(sd, (s32)d);
+
+ return exceptions;
+}
+
+static u32 vfp_single_ftosiz(int sd, int unused, s32 m, u32 fpscr)
+{
+ return vfp_single_ftosi(sd, unused, m, FPSCR_ROUND_TOZERO);
+}
+
+static u32 (* const fop_extfns[32])(int sd, int unused, s32 m, u32 fpscr) = {
+ [FEXT_TO_IDX(FEXT_FCPY)] = vfp_single_fcpy,
+ [FEXT_TO_IDX(FEXT_FABS)] = vfp_single_fabs,
+ [FEXT_TO_IDX(FEXT_FNEG)] = vfp_single_fneg,
+ [FEXT_TO_IDX(FEXT_FSQRT)] = vfp_single_fsqrt,
+ [FEXT_TO_IDX(FEXT_FCMP)] = vfp_single_fcmp,
+ [FEXT_TO_IDX(FEXT_FCMPE)] = vfp_single_fcmpe,
+ [FEXT_TO_IDX(FEXT_FCMPZ)] = vfp_single_fcmpz,
+ [FEXT_TO_IDX(FEXT_FCMPEZ)] = vfp_single_fcmpez,
+ [FEXT_TO_IDX(FEXT_FCVT)] = vfp_single_fcvtd,
+ [FEXT_TO_IDX(FEXT_FUITO)] = vfp_single_fuito,
+ [FEXT_TO_IDX(FEXT_FSITO)] = vfp_single_fsito,
+ [FEXT_TO_IDX(FEXT_FTOUI)] = vfp_single_ftoui,
+ [FEXT_TO_IDX(FEXT_FTOUIZ)] = vfp_single_ftouiz,
+ [FEXT_TO_IDX(FEXT_FTOSI)] = vfp_single_ftosi,
+ [FEXT_TO_IDX(FEXT_FTOSIZ)] = vfp_single_ftosiz,
+};
+
+
+
+
+
+static u32
+vfp_single_fadd_nonnumber(struct vfp_single *vsd, struct vfp_single *vsn,
+ struct vfp_single *vsm, u32 fpscr)
+{
+ struct vfp_single *vsp;
+ u32 exceptions = 0;
+ int tn, tm;
+
+ tn = vfp_single_type(vsn);
+ tm = vfp_single_type(vsm);
+
+ if (tn & tm & VFP_INFINITY) {
+ /*
+ * Two infinities. Are they different signs?
+ */
+ if (vsn->sign ^ vsm->sign) {
+ /*
+ * different signs -> invalid
+ */
+ exceptions = FPSCR_IOC;
+ vsp = &vfp_single_default_qnan;
+ } else {
+ /*
+ * same signs -> valid
+ */
+ vsp = vsn;
+ }
+ } else if (tn & VFP_INFINITY && tm & VFP_NUMBER) {
+ /*
+ * One infinity and one number -> infinity
+ */
+ vsp = vsn;
+ } else {
+ /*
+ * 'n' is a NaN of some type
+ */
+ return vfp_propagate_nan(vsd, vsn, vsm, fpscr);
+ }
+ *vsd = *vsp;
+ return exceptions;
+}
+
+static u32
+vfp_single_add(struct vfp_single *vsd, struct vfp_single *vsn,
+ struct vfp_single *vsm, u32 fpscr)
+{
+ u32 exp_diff, m_sig;
+
+ if (vsn->significand & 0x80000000 ||
+ vsm->significand & 0x80000000) {
+ pr_info("VFP: bad FP values in %s\n", __func__);
+ vfp_single_dump("VSN", vsn);
+ vfp_single_dump("VSM", vsm);
+ }
+
+ /*
+ * Ensure that 'n' is the largest magnitude number. Note that
+ * if 'n' and 'm' have equal exponents, we do not swap them.
+ * This ensures that NaN propagation works correctly.
+ */
+ if (vsn->exponent < vsm->exponent) {
+ struct vfp_single *t = vsn;
+ vsn = vsm;
+ vsm = t;
+ }
+
+ /*
+ * Is 'n' an infinity or a NaN? Note that 'm' may be a number,
+ * infinity or a NaN here.
+ */
+ if (vsn->exponent == 255)
+ return vfp_single_fadd_nonnumber(vsd, vsn, vsm, fpscr);
+
+ /*
+ * We have two proper numbers, where 'vsn' is the larger magnitude.
+ *
+ * Copy 'n' to 'd' before doing the arithmetic.
+ */
+ *vsd = *vsn;
+
+ /*
+ * Align both numbers.
+ */
+ exp_diff = vsn->exponent - vsm->exponent;
+ m_sig = vfp_shiftright32jamming(vsm->significand, exp_diff);
+
+ /*
+ * If the signs are different, we are really subtracting.
+ */
+ if (vsn->sign ^ vsm->sign) {
+ m_sig = vsn->significand - m_sig;
+ if ((s32)m_sig < 0) {
+ vsd->sign = vfp_sign_negate(vsd->sign);
+ m_sig = -m_sig;
+ } else if (m_sig == 0) {
+ vsd->sign = (fpscr & FPSCR_RMODE_MASK) ==
+ FPSCR_ROUND_MINUSINF ? 0x8000 : 0;
+ }
+ } else {
+ m_sig = vsn->significand + m_sig;
+ }
+ vsd->significand = m_sig;
+
+ return 0;
+}
+
+static u32
+vfp_single_multiply(struct vfp_single *vsd, struct vfp_single *vsn, struct vfp_single *vsm, u32 fpscr)
+{
+ vfp_single_dump("VSN", vsn);
+ vfp_single_dump("VSM", vsm);
+
+ /*
+ * Ensure that 'n' is the largest magnitude number. Note that
+ * if 'n' and 'm' have equal exponents, we do not swap them.
+ * This ensures that NaN propagation works correctly.
+ */
+ if (vsn->exponent < vsm->exponent) {
+ struct vfp_single *t = vsn;
+ vsn = vsm;
+ vsm = t;
+ pr_debug("VFP: swapping M <-> N\n");
+ }
+
+ vsd->sign = vsn->sign ^ vsm->sign;
+
+ /*
+ * If 'n' is an infinity or NaN, handle it. 'm' may be anything.
+ */
+ if (vsn->exponent == 255) {
+ if (vsn->significand || (vsm->exponent == 255 && vsm->significand))
+ return vfp_propagate_nan(vsd, vsn, vsm, fpscr);
+ if ((vsm->exponent | vsm->significand) == 0) {
+ *vsd = vfp_single_default_qnan;
+ return FPSCR_IOC;
+ }
+ vsd->exponent = vsn->exponent;
+ vsd->significand = 0;
+ return 0;
+ }
+
+ /*
+ * If 'm' is zero, the result is always zero. In this case,
+ * 'n' may be zero or a number, but it doesn't matter which.
+ */
+ if ((vsm->exponent | vsm->significand) == 0) {
+ vsd->exponent = 0;
+ vsd->significand = 0;
+ return 0;
+ }
+
+ /*
+ * We add 2 to the destination exponent for the same reason as
+ * the addition case - though this time we have +1 from each
+ * input operand.
+ */
+ vsd->exponent = vsn->exponent + vsm->exponent - 127 + 2;
+ vsd->significand = vfp_hi64to32jamming((u64)vsn->significand * vsm->significand);
+
+ vfp_single_dump("VSD", vsd);
+ return 0;
+}
+
+#define NEG_MULTIPLY (1 << 0)
+#define NEG_SUBTRACT (1 << 1)
+
+static u32
+vfp_single_multiply_accumulate(int sd, int sn, s32 m, u32 fpscr, u32 negate, char *func)
+{
+ struct vfp_single vsd, vsp, vsn, vsm;
+ u32 exceptions;
+ s32 v;
+
+ v = vfp_get_float(sn);
+ pr_debug("VFP: s%u = %08x\n", sn, v);
+ vfp_single_unpack(&vsn, v);
+ if (vsn.exponent == 0 && vsn.significand)
+ vfp_single_normalise_denormal(&vsn);
+
+ vfp_single_unpack(&vsm, m);
+ if (vsm.exponent == 0 && vsm.significand)
+ vfp_single_normalise_denormal(&vsm);
+
+ exceptions = vfp_single_multiply(&vsp, &vsn, &vsm, fpscr);
+ if (negate & NEG_MULTIPLY)
+ vsp.sign = vfp_sign_negate(vsp.sign);
+
+ v = vfp_get_float(sd);
+ pr_debug("VFP: s%u = %08x\n", sd, v);
+ vfp_single_unpack(&vsn, v);
+ if (negate & NEG_SUBTRACT)
+ vsn.sign = vfp_sign_negate(vsn.sign);
+
+ exceptions |= vfp_single_add(&vsd, &vsn, &vsp, fpscr);
+
+ return vfp_single_normaliseround(sd, &vsd, fpscr, exceptions, func);
+}
+
+/*
+ * Standard operations
+ */
+
+/*
+ * sd = sd + (sn * sm)
+ */
+static u32 vfp_single_fmac(int sd, int sn, s32 m, u32 fpscr)
+{
+ return vfp_single_multiply_accumulate(sd, sn, m, fpscr, 0, "fmac");
+}
+
+/*
+ * sd = sd - (sn * sm)
+ */
+static u32 vfp_single_fnmac(int sd, int sn, s32 m, u32 fpscr)
+{
+ return vfp_single_multiply_accumulate(sd, sn, m, fpscr, NEG_MULTIPLY, "fnmac");
+}
+
+/*
+ * sd = -sd + (sn * sm)
+ */
+static u32 vfp_single_fmsc(int sd, int sn, s32 m, u32 fpscr)
+{
+ return vfp_single_multiply_accumulate(sd, sn, m, fpscr, NEG_SUBTRACT, "fmsc");
+}
+
+/*
+ * sd = -sd - (sn * sm)
+ */
+static u32 vfp_single_fnmsc(int sd, int sn, s32 m, u32 fpscr)
+{
+ return vfp_single_multiply_accumulate(sd, sn, m, fpscr, NEG_SUBTRACT | NEG_MULTIPLY, "fnmsc");
+}
+
+/*
+ * sd = sn * sm
+ */
+static u32 vfp_single_fmul(int sd, int sn, s32 m, u32 fpscr)
+{
+ struct vfp_single vsd, vsn, vsm;
+ u32 exceptions;
+ s32 n = vfp_get_float(sn);
+
+ pr_debug("VFP: s%u = %08x\n", sn, n);
+
+ vfp_single_unpack(&vsn, n);
+ if (vsn.exponent == 0 && vsn.significand)
+ vfp_single_normalise_denormal(&vsn);
+
+ vfp_single_unpack(&vsm, m);
+ if (vsm.exponent == 0 && vsm.significand)
+ vfp_single_normalise_denormal(&vsm);
+
+ exceptions = vfp_single_multiply(&vsd, &vsn, &vsm, fpscr);
+ return vfp_single_normaliseround(sd, &vsd, fpscr, exceptions, "fmul");
+}
+
+/*
+ * sd = -(sn * sm)
+ */
+static u32 vfp_single_fnmul(int sd, int sn, s32 m, u32 fpscr)
+{
+ struct vfp_single vsd, vsn, vsm;
+ u32 exceptions;
+ s32 n = vfp_get_float(sn);
+
+ pr_debug("VFP: s%u = %08x\n", sn, n);
+
+ vfp_single_unpack(&vsn, n);
+ if (vsn.exponent == 0 && vsn.significand)
+ vfp_single_normalise_denormal(&vsn);
+
+ vfp_single_unpack(&vsm, m);
+ if (vsm.exponent == 0 && vsm.significand)
+ vfp_single_normalise_denormal(&vsm);
+
+ exceptions = vfp_single_multiply(&vsd, &vsn, &vsm, fpscr);
+ vsd.sign = vfp_sign_negate(vsd.sign);
+ return vfp_single_normaliseround(sd, &vsd, fpscr, exceptions, "fnmul");
+}
+
+/*
+ * sd = sn + sm
+ */
+static u32 vfp_single_fadd(int sd, int sn, s32 m, u32 fpscr)
+{
+ struct vfp_single vsd, vsn, vsm;
+ u32 exceptions;
+ s32 n = vfp_get_float(sn);
+
+ pr_debug("VFP: s%u = %08x\n", sn, n);
+
+ /*
+ * Unpack and normalise denormals.
+ */
+ vfp_single_unpack(&vsn, n);
+ if (vsn.exponent == 0 && vsn.significand)
+ vfp_single_normalise_denormal(&vsn);
+
+ vfp_single_unpack(&vsm, m);
+ if (vsm.exponent == 0 && vsm.significand)
+ vfp_single_normalise_denormal(&vsm);
+
+ exceptions = vfp_single_add(&vsd, &vsn, &vsm, fpscr);
+
+ return vfp_single_normaliseround(sd, &vsd, fpscr, exceptions, "fadd");
+}
+
+/*
+ * sd = sn - sm
+ */
+static u32 vfp_single_fsub(int sd, int sn, s32 m, u32 fpscr)
+{
+ /*
+ * Subtraction is addition with one sign inverted.
+ */
+ return vfp_single_fadd(sd, sn, vfp_single_packed_negate(m), fpscr);
+}
+
+/*
+ * sd = sn / sm
+ */
+static u32 vfp_single_fdiv(int sd, int sn, s32 m, u32 fpscr)
+{
+ struct vfp_single vsd, vsn, vsm;
+ u32 exceptions = 0;
+ s32 n = vfp_get_float(sn);
+ int tm, tn;
+
+ pr_debug("VFP: s%u = %08x\n", sn, n);
+
+ vfp_single_unpack(&vsn, n);
+ vfp_single_unpack(&vsm, m);
+
+ vsd.sign = vsn.sign ^ vsm.sign;
+
+ tn = vfp_single_type(&vsn);
+ tm = vfp_single_type(&vsm);
+
+ /*
+ * Is n a NAN?
+ */
+ if (tn & VFP_NAN)
+ goto vsn_nan;
+
+ /*
+ * Is m a NAN?
+ */
+ if (tm & VFP_NAN)
+ goto vsm_nan;
+
+ /*
+ * If n and m are infinity, the result is invalid
+ * If n and m are zero, the result is invalid
+ */
+ if (tm & tn & (VFP_INFINITY|VFP_ZERO))
+ goto invalid;
+
+ /*
+ * If n is infinity, the result is infinity
+ */
+ if (tn & VFP_INFINITY)
+ goto infinity;
+
+ /*
+ * If m is zero, raise div0 exception
+ */
+ if (tm & VFP_ZERO)
+ goto divzero;
+
+ /*
+ * If m is infinity, or n is zero, the result is zero
+ */
+ if (tm & VFP_INFINITY || tn & VFP_ZERO)
+ goto zero;
+
+ if (tn & VFP_DENORMAL)
+ vfp_single_normalise_denormal(&vsn);
+ if (tm & VFP_DENORMAL)
+ vfp_single_normalise_denormal(&vsm);
+
+ /*
+ * Ok, we have two numbers, we can perform division.
+ */
+ vsd.exponent = vsn.exponent - vsm.exponent + 127 - 1;
+ vsm.significand <<= 1;
+ if (vsm.significand <= (2 * vsn.significand)) {
+ vsn.significand >>= 1;
+ vsd.exponent++;
+ }
+ vsd.significand = ((u64)vsn.significand << 32) / vsm.significand;
+ if ((vsd.significand & 0x3f) == 0)
+ vsd.significand |= ((u64)vsm.significand * vsd.significand != (u64)vsn.significand << 32);
+
+ return vfp_single_normaliseround(sd, &vsd, fpscr, 0, "fdiv");
+
+ vsn_nan:
+ exceptions = vfp_propagate_nan(&vsd, &vsn, &vsm, fpscr);
+ pack:
+ vfp_put_float(sd, vfp_single_pack(&vsd));
+ return exceptions;
+
+ vsm_nan:
+ exceptions = vfp_propagate_nan(&vsd, &vsm, &vsn, fpscr);
+ goto pack;
+
+ zero:
+ vsd.exponent = 0;
+ vsd.significand = 0;
+ goto pack;
+
+ divzero:
+ exceptions = FPSCR_DZC;
+ infinity:
+ vsd.exponent = 255;
+ vsd.significand = 0;
+ goto pack;
+
+ invalid:
+ vfp_put_float(sd, vfp_single_pack(&vfp_single_default_qnan));
+ return FPSCR_IOC;
+}
+
+static u32 (* const fop_fns[16])(int sd, int sn, s32 m, u32 fpscr) = {
+ [FOP_TO_IDX(FOP_FMAC)] = vfp_single_fmac,
+ [FOP_TO_IDX(FOP_FNMAC)] = vfp_single_fnmac,
+ [FOP_TO_IDX(FOP_FMSC)] = vfp_single_fmsc,
+ [FOP_TO_IDX(FOP_FNMSC)] = vfp_single_fnmsc,
+ [FOP_TO_IDX(FOP_FMUL)] = vfp_single_fmul,
+ [FOP_TO_IDX(FOP_FNMUL)] = vfp_single_fnmul,
+ [FOP_TO_IDX(FOP_FADD)] = vfp_single_fadd,
+ [FOP_TO_IDX(FOP_FSUB)] = vfp_single_fsub,
+ [FOP_TO_IDX(FOP_FDIV)] = vfp_single_fdiv,
+};
+
+#define FREG_BANK(x) ((x) & 0x18)
+#define FREG_IDX(x) ((x) & 7)
+
+u32 vfp_single_cpdo(u32 inst, u32 fpscr)
+{
+ u32 op = inst & FOP_MASK;
+ u32 exceptions = 0;
+ unsigned int sd = vfp_get_sd(inst);
+ unsigned int sn = vfp_get_sn(inst);
+ unsigned int sm = vfp_get_sm(inst);
+ unsigned int vecitr, veclen, vecstride;
+ u32 (*fop)(int, int, s32, u32);
+
+ veclen = fpscr & FPSCR_LENGTH_MASK;
+ vecstride = 1 + ((fpscr & FPSCR_STRIDE_MASK) == FPSCR_STRIDE_MASK);
+
+ /*
+ * If destination bank is zero, vector length is always '1'.
+ * ARM DDI0100F C5.1.3, C5.3.2.
+ */
+ if (FREG_BANK(sd) == 0)
+ veclen = 0;
+
+ pr_debug("VFP: vecstride=%u veclen=%u\n", vecstride,
+ (veclen >> FPSCR_LENGTH_BIT) + 1);
+
+ fop = (op == FOP_EXT) ? fop_extfns[sn] : fop_fns[FOP_TO_IDX(op)];
+ if (!fop)
+ goto invalid;
+
+ for (vecitr = 0; vecitr <= veclen; vecitr += 1 << FPSCR_LENGTH_BIT) {
+ s32 m = vfp_get_float(sm);
+ u32 except;
+
+ if (op == FOP_EXT)
+ pr_debug("VFP: itr%d (s%u) = op[%u] (s%u=%08x)\n",
+ vecitr >> FPSCR_LENGTH_BIT, sd, sn, sm, m);
+ else
+ pr_debug("VFP: itr%d (s%u) = (s%u) op[%u] (s%u=%08x)\n",
+ vecitr >> FPSCR_LENGTH_BIT, sd, sn,
+ FOP_TO_IDX(op), sm, m);
+
+ except = fop(sd, sn, m, fpscr);
+ pr_debug("VFP: itr%d: exceptions=%08x\n",
+ vecitr >> FPSCR_LENGTH_BIT, except);
+
+ exceptions |= except;
+
+ /*
+ * This ensures that comparisons only operate on scalars;
+ * comparisons always return with one FPSCR status bit set.
+ */
+ if (except & (FPSCR_N|FPSCR_Z|FPSCR_C|FPSCR_V))
+ break;
+
+ /*
+ * CHECK: It appears to be undefined whether we stop when
+ * we encounter an exception. We continue.
+ */
+
+ sd = FREG_BANK(sd) + ((FREG_IDX(sd) + vecstride) & 7);
+ sn = FREG_BANK(sn) + ((FREG_IDX(sn) + vecstride) & 7);
+ if (FREG_BANK(sm) != 0)
+ sm = FREG_BANK(sm) + ((FREG_IDX(sm) + vecstride) & 7);
+ }
+ return exceptions;
+
+ invalid:
+ return (u32)-1;
+}
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