diff mbox

[8/17] Make _Float16 available if HFmode is available

Message ID 1478878647-22547-9-git-send-email-james.greenhalgh@arm.com
State New
Headers show

Commit Message

James Greenhalgh Nov. 11, 2016, 3:37 p.m. UTC 
---
This patch was approved:
  https://gcc.gnu.org/ml/gcc-patches/2016-09/msg02403.html
---

Hi,

Now that we've worked on -fexcess-precision, the comment in targhooks.c
no longer holds. We can now permit _Float16 on any target which provides
HFmode and supports HFmode in libgcc.

Bootstrapped and tested on x86-64, and in series on AArch64.

Thanks,
James

---
2016-11-09  James Greenhalgh  <james.greenhalgh@arm.com>

	* targhooks.c (default_floatn_mode): Enable _Float16 if a target
	provides HFmode.
diff mbox

Patch

diff --git a/gcc/targhooks.c b/gcc/targhooks.c
index 73e1c25..a80b301 100644
--- a/gcc/targhooks.c
+++ b/gcc/targhooks.c
@@ -514,10 +514,12 @@  default_floatn_mode (int n, bool extended)
       switch (n)
 	{
 	case 16:
-	  /* We do not use HFmode for _Float16 by default because the
-	     required excess precision support is not present and the
-	     interactions with promotion of the older __fp16 need to
-	     be worked out.  */
+	  /* Always enable _Float16 if we have basic support for the mode.
+	     Targets can control the range and precision of operations on
+	     the _Float16 type using TARGET_C_EXCESS_PRECISION.  */
+#ifdef HAVE_HFmode
+	  cand = HFmode;
+#endif
 	  break;
 
 	case 32: