From: Richard Earnshaw <rearnsha@arm.com>
Date: Thu, 24 Sep 2015 09:40:06 +0000 (+0000)
Subject: ARM: fp16 Fix PR 67624 - Incorrect conversion of float Infinity to __fp16
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4dfe21acc2072b7dd35cd57ced94cf880b896158;p=gcc.git

ARM: fp16 Fix PR 67624 - Incorrect conversion of float Infinity to __fp16

	PR libgcc/67624
	libgcc:
	* config/arm/fp16.c (__gnu_f2h_internal): Handle infinity correctly.
	gcc/testsuite:
	* gcc.target/arm/fp16-inf.c: New test.

From-SVN: r228082
---

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6dc9d9ea739..fe4f67f7000 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-09-24  Richard Earnshaw  <rearnsha@arm.com>
+
+	PR libgcc/67624
+	* gcc.target/arm/fp16-inf.c: New test.
+
 2015-09-24  Kirill Yukhin <kirill.yukhin@intel.com>
 
 	* gcc.target/i386/avx512vbmi-check.h (main): Fix register
diff --git a/gcc/testsuite/gcc.target/arm/fp16-inf.c b/gcc/testsuite/gcc.target/arm/fp16-inf.c
new file mode 100644
index 00000000000..ce5c197c121
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/fp16-inf.c
@@ -0,0 +1,14 @@
+/* { dg-do run } */
+/* { dg-options "-O -mfp16-format=ieee" } */
+
+/* Conversion of infinity to __fp16 and back again should preserve the
+   value.  */
+volatile float f = __builtin_inf ();
+
+int main ()
+{
+  __fp16 h = f;
+  if (h != __builtin_inf ())
+    __builtin_abort ();
+  return 0;
+}
diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog
index cc5c2c3903b..dee1c115280 100644
--- a/libgcc/ChangeLog
+++ b/libgcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-09-24  Richard Earnshaw  <rearnsha@arm.com>
+
+	PR libgcc/67624
+	* config/arm/fp16.c (__gnu_f2h_internal): Handle infinity correctly.
+
 2015-09-24  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* config.host (*-*-solaris2*): Add t-crtstuff-pic to tmake_file.
diff --git a/libgcc/config/arm/fp16.c b/libgcc/config/arm/fp16.c
index 86a6348aecf..8eaae2b84e7 100644
--- a/libgcc/config/arm/fp16.c
+++ b/libgcc/config/arm/fp16.c
@@ -35,9 +35,12 @@ __gnu_f2h_internal(unsigned int a, int ieee)
     {
       if (!ieee)
 	return sign;
+      if (mantissa == 0)
+	return sign | 0x7c00;	/* Infinity.  */
+      /* Remaining cases are NaNs.  Convert SNaN to QNaN.  */
       return sign | 0x7e00 | (mantissa >> 13);
     }
-  
+
   if (aexp == 0 && mantissa == 0)
     return sign;
 
@@ -49,7 +52,7 @@ __gnu_f2h_internal(unsigned int a, int ieee)
     {
       mask = 0x00ffffff;
       if (aexp >= -25)
-        mask >>= 25 + aexp;
+	mask >>= 25 + aexp;
     }
   else
     mask = 0x00001fff;