[Bug target/85667] ms_abi rules aren't followed when returning short structs with float values

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85667

--- Comment #12 from H.J. Lu <hjl.tools at gmail dot com> ---
I am testing this

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index ffda3e8fd21..f769cb8f75e 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -3153,7 +3153,7 @@ function_arg_64 (const CUMULATIVE_ARGS *cum, machine_mode
mode,

 static rtx
 function_arg_ms_64 (const CUMULATIVE_ARGS *cum, machine_mode mode,
-         machine_mode orig_mode, bool named,
+         machine_mode orig_mode, bool named, const_tree type,
          HOST_WIDE_INT bytes)
 {
   unsigned int regno;
@@ -3173,7 +3173,10 @@ function_arg_ms_64 (const CUMULATIVE_ARGS *cum,
machine_mode mode,
   if (TARGET_SSE && (mode == SFmode || mode == DFmode))
     {
       if (named)
-  regno = cum->regno + FIRST_SSE_REG;
+  {
+    if (type == NULL_TREE || !AGGREGATE_TYPE_P (type))
+      regno = cum->regno + FIRST_SSE_REG;
+  }
       else
   {
     rtx t1, t2;
@@ -3253,7 +3256,8 @@ ix86_function_arg (cumulative_args_t cum_v, const
function_arg_info &arg)
       enum calling_abi call_abi = cum ? cum->call_abi : ix86_abi;

       if (call_abi == MS_ABI)
-  reg = function_arg_ms_64 (cum, mode, arg.mode, arg.named, bytes);
+  reg = function_arg_ms_64 (cum, mode, arg.mode, arg.named,
+             arg.type, bytes);
       else
   reg = function_arg_64 (cum, mode, arg.mode, arg.type, arg.named);
     }