[PATCH] Remove __builtin_ia32_readeflags_u32/__builtin_ia32_writeeflags_u32 builtins for TARGET_64BIT (PR target/85511)

[Jakub Jelinek]

Hi!

These two *_u32 builtins are defined also in -m64 mode, but share the
builtin codes with the *_u64 ones and the expansion of them uses word_mode.

The following patch just removes them, ia32intrin.h uses the u32 suffixed
ones only when __x86_64__ is not defined, bootstrapped/regtested on
x86_64-linux and i686-linux, ok for trunk?

A variant would be to use separate IX86_BUILTIN_ codes for the 32-bit and
64-bit builtins and add separate expansion for them, but that looks like
overkill to me, people should use __readeflags/__writeeflags anyway and
those do the right thing.

2018-04-24  Jakub Jelinek  <ja...@redhat.com>

        PR target/85511
        * config/i386/i386.c (ix86_init_mmx_sse_builtins): Don't define
        __builtin_ia32_readeflags_u32 and __builtin_ia32_writeeflags_u32
        if TARGET_64BIT.

        * gcc.target/i386/pr85511.c: New test.

--- gcc/config/i386/i386.c.jj   2018-04-24 09:37:36.029459208 +0200
+++ gcc/config/i386/i386.c      2018-04-24 10:37:01.258882134 +0200
@@ -31934,14 +31934,20 @@ ix86_init_mmx_sse_builtins (void)
               IX86_BUILTIN_SBB64);
 
   /* Read/write FLAGS.  */
-  def_builtin (0, "__builtin_ia32_readeflags_u32",
-               UNSIGNED_FTYPE_VOID, IX86_BUILTIN_READ_FLAGS);
-  def_builtin (OPTION_MASK_ISA_64BIT, "__builtin_ia32_readeflags_u64",
-               UINT64_FTYPE_VOID, IX86_BUILTIN_READ_FLAGS);
-  def_builtin (0, "__builtin_ia32_writeeflags_u32",
-               VOID_FTYPE_UNSIGNED, IX86_BUILTIN_WRITE_FLAGS);
-  def_builtin (OPTION_MASK_ISA_64BIT, "__builtin_ia32_writeeflags_u64",
-               VOID_FTYPE_UINT64, IX86_BUILTIN_WRITE_FLAGS);
+  if (TARGET_64BIT)
+    {
+      def_builtin (OPTION_MASK_ISA_64BIT, "__builtin_ia32_readeflags_u64",
+                  UINT64_FTYPE_VOID, IX86_BUILTIN_READ_FLAGS);
+      def_builtin (OPTION_MASK_ISA_64BIT, "__builtin_ia32_writeeflags_u64",
+                  VOID_FTYPE_UINT64, IX86_BUILTIN_WRITE_FLAGS);
+    }
+  else
+    {
+      def_builtin (0, "__builtin_ia32_readeflags_u32",
+                  UNSIGNED_FTYPE_VOID, IX86_BUILTIN_READ_FLAGS);
+      def_builtin (0, "__builtin_ia32_writeeflags_u32",
+                  VOID_FTYPE_UNSIGNED, IX86_BUILTIN_WRITE_FLAGS);
+    }
 
   /* CLFLUSHOPT.  */
   def_builtin (OPTION_MASK_ISA_CLFLUSHOPT, "__builtin_ia32_clflushopt",
--- gcc/testsuite/gcc.target/i386/pr85511.c.jj  2018-04-24 10:45:18.099260629 
+0200
+++ gcc/testsuite/gcc.target/i386/pr85511.c     2018-04-24 10:47:46.069374103 
+0200
@@ -0,0 +1,15 @@
+/* PR target/85511 */
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-function-declaration" } */
+
+unsigned int
+foo (void)
+{
+  return __builtin_ia32_readeflags_u32 ();     /* { dg-warning "implicit 
declaration of function" "" { target { ! ia32 } } } */
+}
+
+void
+bar (unsigned int x)
+{
+  __builtin_ia32_writeeflags_u32 (x);          /* { dg-warning "implicit 
declaration of function" "" { target { ! ia32 } } } */
+}

        Jakub