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 6dc9d9ea7391fc9c78afad60ff3f2492664b6426..fe4f67f70009cfb51dff1706921210ca3dc6a9be 100644 (file)
--- 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 (file)
index 0000000..ce5c197
--- /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 cc5c2c3903b1e4301f6c757e5f1721bbe83621b7..dee1c11528035df53c416025c846c8132b69d69c 100644 (file)
--- 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 86a6348aecf9db181bf2d9d9f99ebe798c21fe59..8eaae2b84e76b2efd4a7dfb156396b34f1ce04ec 100644 (file)
--- 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;