i386: Allow MMX register modes in SSE registers

In 64-bit mode, SSE2 can be used to emulate MMX instructions without
3DNOW.  We can use SSE2 to support MMX register modes.

	PR target/89021
	* config/i386/i386-c.c (ix86_target_macros_internal): Define
	__MMX_WITH_SSE__ for TARGET_MMX_WITH_SSE.
	* config/i386/i386.c (ix86_set_reg_reg_cost): Add support for
	TARGET_MMX_WITH_SSE with VALID_MMX_REG_MODE.
	(ix86_vector_mode_supported_p): Likewise.
	* config/i386/i386.h (TARGET_MMX_WITH_SSE): New.

From-SVN: r271213

gcc/ChangeLog

+2019-05-15  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/89021
+	* config/i386/i386-c.c (ix86_target_macros_internal): Define
+	__MMX_WITH_SSE__ for TARGET_MMX_WITH_SSE.
+	* config/i386/i386.c (ix86_set_reg_reg_cost): Add support for
+	TARGET_MMX_WITH_SSE with VALID_MMX_REG_MODE.
+	(ix86_vector_mode_supported_p): Likewise.
+	* config/i386/i386.h (TARGET_MMX_WITH_SSE): New.
+
 2019-05-15  Martin Liska  <mliska@suse.cz>
 
 	PR middle-end/90478

gcc/config/i386/i386-c.c

@@ -550,6 +550,8 @@ ix86_target_macros_internal (HOST_WIDE_INT isa_flag,
     def_or_undef (parse_in, "__PTWRITE__");
   if (isa_flag2 & OPTION_MASK_ISA_AVX512BF16)
     def_or_undef (parse_in, "__AVX512BF16__");
+  if (TARGET_MMX_WITH_SSE)
+    def_or_undef (parse_in, "__MMX_WITH_SSE__");
   if (TARGET_IAMCU)
     {
       def_or_undef (parse_in, "__iamcu");

gcc/config/i386/i386.c

@@ -18882,7 +18882,8 @@ ix86_set_reg_reg_cost (machine_mode mode)
 	  || (TARGET_AVX && VALID_AVX256_REG_MODE (mode))
 	  || (TARGET_SSE2 && VALID_SSE2_REG_MODE (mode))
 	  || (TARGET_SSE && VALID_SSE_REG_MODE (mode))
-	  || (TARGET_MMX && VALID_MMX_REG_MODE (mode)))
+	  || ((TARGET_MMX || TARGET_MMX_WITH_SSE)
+	      && VALID_MMX_REG_MODE (mode)))
 	units = GET_MODE_SIZE (mode);
     }
 
@@ -20611,7 +20612,7 @@ ix86_vector_mode_supported_p (machine_mode mode)
     return true;
   if (TARGET_AVX512F && VALID_AVX512F_REG_MODE (mode))
     return true;
-  if (TARGET_MMX && VALID_MMX_REG_MODE (mode))
+  if ((TARGET_MMX || TARGET_MMX_WITH_SSE) && VALID_MMX_REG_MODE (mode))
     return true;
   if (TARGET_3DNOW && VALID_MMX_REG_MODE_3DNOW (mode))
     return true;

gcc/config/i386/i386.h

@@ -203,6 +203,8 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #define TARGET_16BIT	TARGET_CODE16
 #define TARGET_16BIT_P(x)	TARGET_CODE16_P(x)
 
+#define TARGET_MMX_WITH_SSE	(TARGET_64BIT && TARGET_SSE2)
+
 #include "config/vxworks-dummy.h"
 
 #include "config/i386/i386-opts.h"