1 files changed, 143 insertions, 0 deletions
diff --git a/arch/mips/math-emu/dp_div.c b/arch/mips/math-emu/dp_div.c
new file mode 100644
index 000000000..ac1ecc462
--- /dev/null
+++ b/arch/mips/math-emu/dp_div.c
@@ -0,0 +1,143 @@
+// 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"
+
+union ieee754dp ieee754dp_div(union ieee754dp x, union ieee754dp y)
+{
+	u64 rm;
+	int re;
+	u64 bm;
+
+	COMPXDP;
+	COMPYDP;
+
+	EXPLODEXDP;
+	EXPLODEYDP;
+
+	ieee754_clearcx();
+
+	FLUSHXDP;
+	FLUSHYDP;
+
+	switch (CLPAIR(xc, yc)) {
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
+		return ieee754dp_nanxcpt(y);
+
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
+	case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
+		return ieee754dp_nanxcpt(x);
+
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
+		return y;
+
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
+	case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
+		return x;
+
+
+	/*
+	 * Infinity handling
+	 */
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+		ieee754_setcx(IEEE754_INVALID_OPERATION);
+		return ieee754dp_indef();
+
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+		return ieee754dp_zero(xs ^ ys);
+
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
+		return ieee754dp_inf(xs ^ ys);
+
+	/*
+	 * Zero handling
+	 */
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+		ieee754_setcx(IEEE754_INVALID_OPERATION);
+		return ieee754dp_indef();
+
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+		ieee754_setcx(IEEE754_ZERO_DIVIDE);
+		return ieee754dp_inf(xs ^ ys);
+
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+		return ieee754dp_zero(xs == ys ? 0 : 1);
+
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
+		DPDNORMX;
+		fallthrough;
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
+		DPDNORMY;
+		break;
+
+	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
+		DPDNORMX;
+		break;
+
+	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
+		break;
+	}
+	assert(xm & DP_HIDDEN_BIT);
+	assert(ym & DP_HIDDEN_BIT);
+
+	/* provide rounding space */
+	xm <<= 3;
+	ym <<= 3;
+
+	/* now the dirty work */
+
+	rm = 0;
+	re = xe - ye;
+
+	for (bm = DP_MBIT(DP_FBITS + 2); bm; bm >>= 1) {
+		if (xm >= ym) {
+			xm -= ym;
+			rm |= bm;
+			if (xm == 0)
+				break;
+		}
+		xm <<= 1;
+	}
+
+	rm <<= 1;
+	if (xm)
+		rm |= 1;	/* have remainder, set sticky */
+
+	assert(rm);
+
+	/*
+	 * Normalise rm to rounding precision ?
+	 */
+	while ((rm >> (DP_FBITS + 3)) == 0) {
+		rm <<= 1;
+		re--;
+	}
+
+	return ieee754dp_format(xs == ys ? 0 : 1, re, rm);
+}