[PATCH, i386]: Fix PR 60205: No ABI warning for AVX-512

[Uros Bizjak]

Hello!

Just following what AVX warnings do.

2014-02-18  Uros Bizjak  <ubiz...@gmail.com>

    PR target/60205
    * config/i386/i386.h (struct ix86_args): Add warn_avx512f.
    * config/i386/i386.c (init_cumulative_args): Initialize warn_avx512f.
    (type_natural_mode): Warn ABI change when %zmm register is not
    available for AVX512F vector value passing.

testsuite/ChangeLog:

2014-02-18  Uros Bizjak  <ubiz...@gmail.com>

    PR target/60205
    * gcc.target/i386/pr60205-1.c: New test.
    * gcc.target/i386/pr60205-2.c: Ditto.

Bootstrapped and regression tested on x86_64-pc-linux-gnu {,-m32} ,
will commit to mainline later today.

Uros.

Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c  (revision 207846)
+++ config/i386/i386.c  (working copy)
@@ -6129,6 +6129,7 @@ init_cumulative_args (CUMULATIVE_ARGS *cum,  /* Ar
     }
   if (TARGET_MMX)
     cum->mmx_nregs = MMX_REGPARM_MAX;
+  cum->warn_avx512f = true;
   cum->warn_avx = true;
   cum->warn_sse = true;
   cum->warn_mmx = true;
@@ -6154,6 +6155,7 @@ init_cumulative_args (CUMULATIVE_ARGS *cum,  /* Ar
          cum->nregs = 0;
          cum->sse_nregs = 0;
          cum->mmx_nregs = 0;
+         cum->warn_avx512f = 0;
          cum->warn_avx = 0;
          cum->warn_sse = 0;
          cum->warn_mmx = 0;
@@ -6211,7 +6213,7 @@ type_natural_mode (const_tree type, const CUMULATI
   if (TREE_CODE (type) == VECTOR_TYPE && !VECTOR_MODE_P (mode))
     {
       HOST_WIDE_INT size = int_size_in_bytes (type);
-      if ((size == 8 || size == 16 || size == 32)
+      if ((size == 8 || size == 16 || size == 32 || size == 64)
          /* ??? Generic code allows us to create width 1 vectors.  Ignore.  */
          && TYPE_VECTOR_SUBPARTS (type) > 1)
        {
@@ -6227,8 +6229,30 @@ type_natural_mode (const_tree type, const CUMULATI
            if (GET_MODE_NUNITS (mode) == TYPE_VECTOR_SUBPARTS (type)
                && GET_MODE_INNER (mode) == innermode)
              {
-               if (size == 32 && !TARGET_AVX)
+               if (size == 64 && !TARGET_AVX512F)
                  {
+                   static bool warnedavx512f;
+                   static bool warnedavx512f_ret;
+
+                   if (cum
+                       && !warnedavx512f
+                       && cum->warn_avx512f)
+                     {
+                       warnedavx512f = true;
+                       warning (0, "AVX512F vector argument without AVX512F "
+                                "enabled changes the ABI");
+                     }
+                   else if (in_return & !warnedavx512f_ret)
+                     {
+                       warnedavx512f_ret = true;
+                       warning (0, "AVX512F vector return without AVX512F "
+                                "enabled changes the ABI");
+                     }
+
+                   return TYPE_MODE (type);
+                 }
+               else if (size == 32 && !TARGET_AVX)
+                 {
                    static bool warnedavx;
                    static bool warnedavx_ret;
 
Index: config/i386/i386.h
===================================================================
--- config/i386/i386.h  (revision 207846)
+++ config/i386/i386.h  (working copy)
@@ -1606,6 +1606,8 @@ typedef struct ix86_args {
                                   is used */
   int sse_words;               /* # sse words passed so far */
   int sse_nregs;               /* # sse registers available for passing */
+  int warn_avx512f;            /* True when we want to warn
+                                  about AVX512F ABI.  */
   int warn_avx;                        /* True when we want to warn about AVX 
ABI.  */
   int warn_sse;                        /* True when we want to warn about SSE 
ABI.  */
   int warn_mmx;                        /* True when we want to warn about MMX 
ABI.  */
Index: testsuite/gcc.target/i386/pr60205-1.c
===================================================================
--- testsuite/gcc.target/i386/pr60205-1.c       (revision 0)
+++ testsuite/gcc.target/i386/pr60205-1.c       (working copy)
@@ -0,0 +1,14 @@
+/* PR target/60205 */
+/* { dg-options "-O2 -mno-avx512f -Wno-psabi" } */
+/* { dg-skip-if "no AVX512F vector" { *-*-mingw* } } */
+
+typedef int __v16si __attribute__ ((__vector_size__ (64)));
+
+extern __v16si x;
+
+extern void bar (__v16si);
+void
+foo (void)
+{
+  bar (x); /* { dg-message "warning: AVX512F vector argument without AVX512F 
enabled changes the ABI" } */
+}
Index: testsuite/gcc.target/i386/pr60205-2.c
===================================================================
--- testsuite/gcc.target/i386/pr60205-2.c       (revision 0)
+++ testsuite/gcc.target/i386/pr60205-2.c       (working copy)
@@ -0,0 +1,13 @@
+/* PR target/60205 */
+/* { dg-options "-O2 -mno-avx512f" } */
+/* { dg-skip-if "no AVX512F vector" { *-*-mingw* } } */
+
+typedef int __v16si __attribute__ ((__vector_size__ (64)));
+
+extern __v16si x;
+
+__v16si
+foo (void)
+{ /* { dg-warning "AVX512F vector return without AVX512F enabled changes the 
ABI" } */
+  return x;
+}