[PATCH 2/3] [x86] implement TARGET_MODE_CAN_TRANSFER_BITS

[Richard Biener]

The following implements the hook, excluding x87 modes for scalar
and complex float modes.

Bootstrapped and tested on x86_64-unknown-linux-gnu.

OK this way?

Thanks,
Richard.

        * i386.cc (TARGET_MODE_CAN_TRANSFER_BITS): Define.
        (ix86_mode_can_transfer_bits): New function.
---
 gcc/config/i386/i386.cc | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 12d15feb5e9..9869c44ee15 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -26113,6 +26113,25 @@ ix86_have_ccmp ()
   return (bool) TARGET_APX_CCMP;
 }
 
+/* Implement TARGET_MODE_CAN_TRANSFER_BITS.  */
+static bool
+ix86_mode_can_transfer_bits (machine_mode mode)
+{
+  if (GET_MODE_CLASS (mode) == MODE_FLOAT
+      || GET_MODE_CLASS (mode) == MODE_COMPLEX_FLOAT)
+    switch (GET_MODE_INNER (mode))
+      {
+      case SFmode:
+      case DFmode:
+       /* These suffer from normalization upon load when not using SSE.  */
+       return !(ix86_fpmath & FPMATH_387);
+      default:
+       return true;
+      }
+
+  return true;
+}
+
 /* Target-specific selftests.  */
 
 #if CHECKING_P
@@ -26959,6 +26978,9 @@ ix86_libgcc_floating_mode_supported_p
 #undef TARGET_HAVE_CCMP
 #define TARGET_HAVE_CCMP ix86_have_ccmp
 
+#undef TARGET_MODE_CAN_TRANSFER_BITS
+#define TARGET_MODE_CAN_TRANSFER_BITS ix86_mode_can_transfer_bits
+
 static bool
 ix86_libc_has_fast_function (int fcode ATTRIBUTE_UNUSED)
 {
-- 
2.43.0