From 9ef6ca4235b7a66aefa432295c02b4df64a53f2e Mon Sep 17 00:00:00 2001
From: Szabolcs Nagy <nsz@port70.net>
Date: Sun, 22 Oct 2017 13:51:35 +0000
Subject: math: add single precision error handling functions

These are supposed to be used in tail call positions when handling
special cases in new code. (fp exceptions may be raised "naturally"
by the common code path if special casing is more effort.)

This implements the error handling apis used in
https://github.com/ARM-software/optimized-routines
without errno setting.
---
 src/internal/libm.h        | 7 +++++++
 src/math/__math_divzerof.c | 6 ++++++
 src/math/__math_invalidf.c | 6 ++++++
 src/math/__math_oflowf.c   | 6 ++++++
 src/math/__math_uflowf.c   | 6 ++++++
 src/math/__math_xflowf.c   | 6 ++++++
 6 files changed, 37 insertions(+)
 create mode 100644 src/math/__math_divzerof.c
 create mode 100644 src/math/__math_invalidf.c
 create mode 100644 src/math/__math_oflowf.c
 create mode 100644 src/math/__math_uflowf.c
 create mode 100644 src/math/__math_xflowf.c

(limited to 'src')

diff --git a/src/internal/libm.h b/src/internal/libm.h
index 09fcfde3..a52a0b83 100644
--- a/src/internal/libm.h
+++ b/src/internal/libm.h
@@ -216,4 +216,11 @@ extern int __signgam;
 hidden double __lgamma_r(double, int *);
 hidden float __lgammaf_r(float, int *);
 
+/* error handling functions */
+hidden float __math_xflowf(uint32_t, float);
+hidden float __math_uflowf(uint32_t);
+hidden float __math_oflowf(uint32_t);
+hidden float __math_divzerof(uint32_t);
+hidden float __math_invalidf(float);
+
 #endif
diff --git a/src/math/__math_divzerof.c b/src/math/__math_divzerof.c
new file mode 100644
index 00000000..ce046f3e
--- /dev/null
+++ b/src/math/__math_divzerof.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+float __math_divzerof(uint32_t sign)
+{
+	return fp_barrierf(sign ? -1.0f : 1.0f) / 0.0f;
+}
diff --git a/src/math/__math_invalidf.c b/src/math/__math_invalidf.c
new file mode 100644
index 00000000..357d4b12
--- /dev/null
+++ b/src/math/__math_invalidf.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+float __math_invalidf(float x)
+{
+	return (x - x) / (x - x);
+}
diff --git a/src/math/__math_oflowf.c b/src/math/__math_oflowf.c
new file mode 100644
index 00000000..fa7d0620
--- /dev/null
+++ b/src/math/__math_oflowf.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+float __math_oflowf(uint32_t sign)
+{
+	return __math_xflowf(sign, 0x1p97f);
+}
diff --git a/src/math/__math_uflowf.c b/src/math/__math_uflowf.c
new file mode 100644
index 00000000..94d50f2b
--- /dev/null
+++ b/src/math/__math_uflowf.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+float __math_uflowf(uint32_t sign)
+{
+	return __math_xflowf(sign, 0x1p-95f);
+}
diff --git a/src/math/__math_xflowf.c b/src/math/__math_xflowf.c
new file mode 100644
index 00000000..f2c84784
--- /dev/null
+++ b/src/math/__math_xflowf.c
@@ -0,0 +1,6 @@
+#include "libm.h"
+
+float __math_xflowf(uint32_t sign, float y)
+{
+	return eval_as_float(fp_barrierf(sign ? -y : y) * y);
+}
-- 
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