>From bb149b430c83e697732749f75965d83edb82d43d Mon Sep 17 00:00:00 2001
From: Szabolcs Nagy <nsz@port70.net>
Date: Fri, 30 Nov 2018 21:15:23 +0000
Subject: [PATCH 08/18] math: add double precision error handling functions

---
 src/internal/libm.h       | 5 +++++
 src/math/__math_divzero.c | 6 ++++++
 src/math/__math_invalid.c | 6 ++++++
 src/math/__math_oflow.c   | 6 ++++++
 src/math/__math_uflow.c   | 6 ++++++
 src/math/__math_xflow.c   | 6 ++++++
 6 files changed, 35 insertions(+)
 create mode 100644 src/math/__math_divzero.c
 create mode 100644 src/math/__math_invalid.c
 create mode 100644 src/math/__math_oflow.c
 create mode 100644 src/math/__math_uflow.c
 create mode 100644 src/math/__math_xflow.c

diff --git a/src/internal/libm.h b/src/internal/libm.h
index a52a0b83..62da4bdb 100644
--- a/src/internal/libm.h
+++ b/src/internal/libm.h
@@ -222,5 +222,10 @@ hidden float __math_uflowf(uint32_t);
 hidden float __math_oflowf(uint32_t);
 hidden float __math_divzerof(uint32_t);
 hidden float __math_invalidf(float);
+hidden double __math_xflow(uint32_t, double);
+hidden double __math_uflow(uint32_t);
+hidden double __math_oflow(uint32_t);
+hidden double __math_divzero(uint32_t);
+hidden double __math_invalid(double);
 
 #endif
diff --git a/src/math/__math_divzero.c b/src/math/__math_divzero.c
new file mode 100644
index 00000000..59d21350
--- /dev/null
+++ b/src/math/__math_divzero.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+double __math_divzero(uint32_t sign)
+{
+	return fp_barrier(sign ? -1.0 : 1.0) / 0.0;
+}
diff --git a/src/math/__math_invalid.c b/src/math/__math_invalid.c
new file mode 100644
index 00000000..17740490
--- /dev/null
+++ b/src/math/__math_invalid.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+double __math_invalid(double x)
+{
+	return (x - x) / (x - x);
+}
diff --git a/src/math/__math_oflow.c b/src/math/__math_oflow.c
new file mode 100644
index 00000000..c85dbf98
--- /dev/null
+++ b/src/math/__math_oflow.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+double __math_oflow(uint32_t sign)
+{
+	return __math_xflow(sign, 0x1p769);
+}
diff --git a/src/math/__math_uflow.c b/src/math/__math_uflow.c
new file mode 100644
index 00000000..b90594ae
--- /dev/null
+++ b/src/math/__math_uflow.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+double __math_uflow(uint32_t sign)
+{
+	return __math_xflow(sign, 0x1p-767);
+}
diff --git a/src/math/__math_xflow.c b/src/math/__math_xflow.c
new file mode 100644
index 00000000..744203c4
--- /dev/null
+++ b/src/math/__math_xflow.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+double __math_xflow(uint32_t sign, double y)
+{
+	return eval_as_double(fp_barrier(sign ? -y : y) * y);
+}
-- 
2.19.1