1 files changed, 100 insertions, 0 deletions

diff --git a/arch/mips/math-emu/dp_tlong.c b/arch/mips/math-emu/dp_tlong.c
new file mode 100644
index 000000000..c61ef02d4
--- /dev/null
+++ b/arch/mips/math-emu/dp_tlong.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* IEEE754 floating point arithmetic
+ * double precision: common utilities
+ */
+/*
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.
+ */
+
+#include "ieee754dp.h"
+
+s64 ieee754dp_tlong(union ieee754dp x)
+{
+        u64 residue;
+        int round;
+        int sticky;
+        int odd;
+
+        COMPXDP;
+
+        ieee754_clearcx();
+
+        EXPLODEXDP;
+        FLUSHXDP;
+
+        switch (xc) {
+        case IEEE754_CLASS_SNAN:
+        case IEEE754_CLASS_QNAN:
+                ieee754_setcx(IEEE754_INVALID_OPERATION);
+                return ieee754di_indef();
+
+        case IEEE754_CLASS_INF:
+                ieee754_setcx(IEEE754_INVALID_OPERATION);
+                return ieee754di_overflow(xs);
+
+        case IEEE754_CLASS_ZERO:
+                return 0;
+
+        case IEEE754_CLASS_DNORM:
+        case IEEE754_CLASS_NORM:
+                break;
+        }
+        if (xe >= 63) {
+                /* look for valid corner case */
+                if (xe == 63 && xs && xm == DP_HIDDEN_BIT)
+                        return -0x8000000000000000LL;
+                /* Set invalid. We will only use overflow for floating
+                   point overflow */
+                ieee754_setcx(IEEE754_INVALID_OPERATION);
+                return ieee754di_overflow(xs);
+        }
+        /* oh gawd */
+        if (xe > DP_FBITS) {
+                xm <<= xe - DP_FBITS;
+        } else if (xe < DP_FBITS) {
+                if (xe < -1) {
+                        residue = xm;
+                        round = 0;
+                        sticky = residue != 0;
+                        xm = 0;
+                } else {
+                        /* Shifting a u64 64 times does not work,
+                        * so we do it in two steps. Be aware that xe
+                        * may be -1 */
+                        residue = xm << (xe + 1);
+                        residue <<= 63 - DP_FBITS;
+                        round = (residue >> 63) != 0;
+                        sticky = (residue << 1) != 0;
+                        xm >>= DP_FBITS - xe;
+                }
+                odd = (xm & 0x1) != 0x0;
+                switch (ieee754_csr.rm) {
+                case FPU_CSR_RN:
+                        if (round && (sticky || odd))
+                                xm++;
+                        break;
+                case FPU_CSR_RZ:
+                        break;
+                case FPU_CSR_RU:        /* toward +Infinity */
+                        if ((round || sticky) && !xs)
+                                xm++;
+                        break;
+                case FPU_CSR_RD:        /* toward -Infinity */
+                        if ((round || sticky) && xs)
+                                xm++;
+                        break;
+                }
+                if ((xm >> 63) != 0) {
+                        /* This can happen after rounding */
+                        ieee754_setcx(IEEE754_INVALID_OPERATION);
+                        return ieee754di_overflow(xs);
+                }
+                if (round || sticky)
+                        ieee754_setcx(IEEE754_INEXACT);
+        }
+        if (xs)
+                return -xm;
+        else
+                return xm;
+}