re PR target/88521 (GCC from r266355 miscompiles x265 for mingw-w64 target)

PR target/88521
	* config/i386/i386.c (function_value_ms_64): Return small sturct in
	AX_REG and float/double in FIRST_SSE_REG for 4 or 8 byte modes.

From-SVN: r267622

gcc/ChangeLog

+2018-12-26  Mateusz B  <mateuszb@poczta.onet.pl>
+
+	PR target/88521
+	* config/i386/i386.c (function_value_ms_64): Return small sturct in
+	AX_REG and float/double in FIRST_SSE_REG for 4 or 8 byte modes.
+
 2019-01-05  Jan Hubicka  <hubicka@ucw.cz>
 
 	PR tree-opt/86020

gcc/config/i386/i386.c

@@ -9063,6 +9063,13 @@ function_value_ms_64 (machine_mode orig_mode, machine_mode mode,
 	      && !COMPLEX_MODE_P (mode))
 	    regno = FIRST_SSE_REG;
 	  break;
+	case 8:
+	case 4:
+	  if (valtype != NULL_TREE && AGGREGATE_TYPE_P (valtype))
+	    break;
+	  if (mode == SFmode || mode == DFmode)
+	    regno = FIRST_SSE_REG;
+	  break;
 	default:
 	  break;
         }

gcc/testsuite/ChangeLog

+2018-12-26  Mateusz B  <mateuszb@poczta.onet.pl>
+
+	PR target/88521
+	* gcc.target/i386/pr88521.c: New testcase.
+
 2019-01-06  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/88658

gcc/testsuite/gcc.target/i386/pr88521.c

+/* { dg-do compile { target lp64 } } */
+/* { dg-options "-O2" } */
+/* { dg-final { scan-assembler-times "movl\[^\n\r]*, %eax|mov\[ \t]*eax," 1 } } */
+/* { dg-final { scan-assembler-times "movss\[^\n\r]*, %xmm" 1 } } */
+/* { dg-final { scan-assembler-times "movsd\[^\n\r]*, %xmm" 1 } } */
+typedef struct
+{
+  float x;
+} Float;
+
+Float  __attribute__((ms_abi)) fn1()
+{
+  Float v;
+  v.x = 3.145F;
+  return v;
+}
+
+float  __attribute__((ms_abi))  fn2 ()
+{
+  float v;
+  v = 3.145F;
+  return v;
+}
+
+double  __attribute__((ms_abi))  fn3 ()
+{
+  double v;
+  v = 3.145;
+  return v;
+}