i386: Add GENERIC and GIMPLE folders of __builtin_ia32_{min,max}* [PR116738]

The following patch adds GENERIC and GIMPLE folders for various
x86 min/max builtins.
As discussed, these builtins have effectively x < y ? x : y
(or x > y ? x : y) behavior.
The GENERIC folding is done if all the (relevant) arguments are
constants (such as VECTOR_CST for vectors) and is done because
the GIMPLE folding can't easily handle masking, rounding and the
ss/sd cases (in a way that it would be pattern recognized back to the
corresponding instructions).  The GIMPLE folding is also done just
for TARGET_SSE4 or later when optimizing, otherwise it is apparently
not matched back.

2024-09-25  Jakub Jelinek  <jakub@redhat.com>

	PR target/116738
	* config/i386/i386.cc (ix86_fold_builtin): Handle
	IX86_BUILTIN_M{IN,AX}{S,P}{S,H,D}*.
	(ix86_gimple_fold_builtin): Handle IX86_BUILTIN_M{IN,AX}P{S,H,D}*.

	* gcc.target/i386/avx512f-pr116738-1.c: New test.
	* gcc.target/i386/avx512f-pr116738-2.c: New test.

3 files changed, 266 insertions, 0 deletions

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index cfa84ed..ad2e7b4 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -18514,6 +18514,8 @@ ix86_fold_builtin (tree fndecl, int n_args,
 	= (enum ix86_builtins) DECL_MD_FUNCTION_CODE (fndecl);
       enum rtx_code rcode;
       bool is_vshift;
+      enum tree_code tcode;
+      bool is_scalar;
       unsigned HOST_WIDE_INT mask;
 
       switch (fn_code)
@@ -18963,6 +18965,131 @@ ix86_fold_builtin (tree fndecl, int n_args,
 	    }
 	  break;
 
+	case IX86_BUILTIN_MINSS:
+	case IX86_BUILTIN_MINSH_MASK:
+	  tcode = LT_EXPR;
+	  is_scalar = true;
+	  goto do_minmax;
+
+	case IX86_BUILTIN_MAXSS:
+	case IX86_BUILTIN_MAXSH_MASK:
+	  tcode = GT_EXPR;
+	  is_scalar = true;
+	  goto do_minmax;
+
+	case IX86_BUILTIN_MINPS:
+	case IX86_BUILTIN_MINPD:
+	case IX86_BUILTIN_MINPS256:
+	case IX86_BUILTIN_MINPD256:
+	case IX86_BUILTIN_MINPS512:
+	case IX86_BUILTIN_MINPD512:
+	case IX86_BUILTIN_MINPS128_MASK:
+	case IX86_BUILTIN_MINPD128_MASK:
+	case IX86_BUILTIN_MINPS256_MASK:
+	case IX86_BUILTIN_MINPD256_MASK:
+	case IX86_BUILTIN_MINPH128_MASK:
+	case IX86_BUILTIN_MINPH256_MASK:
+	case IX86_BUILTIN_MINPH512_MASK:
+	  tcode = LT_EXPR;
+	  is_scalar = false;
+	  goto do_minmax;
+
+	case IX86_BUILTIN_MAXPS:
+	case IX86_BUILTIN_MAXPD:
+	case IX86_BUILTIN_MAXPS256:
+	case IX86_BUILTIN_MAXPD256:
+	case IX86_BUILTIN_MAXPS512:
+	case IX86_BUILTIN_MAXPD512:
+	case IX86_BUILTIN_MAXPS128_MASK:
+	case IX86_BUILTIN_MAXPD128_MASK:
+	case IX86_BUILTIN_MAXPS256_MASK:
+	case IX86_BUILTIN_MAXPD256_MASK:
+	case IX86_BUILTIN_MAXPH128_MASK:
+	case IX86_BUILTIN_MAXPH256_MASK:
+	case IX86_BUILTIN_MAXPH512_MASK:
+	  tcode = GT_EXPR;
+	  is_scalar = false;
+	do_minmax:
+	  gcc_assert (n_args >= 2);
+	  if (TREE_CODE (args[0]) != VECTOR_CST
+	      || TREE_CODE (args[1]) != VECTOR_CST)
+	    break;
+	  mask = HOST_WIDE_INT_M1U;
+	  if (n_args > 2)
+	    {
+	      gcc_assert (n_args >= 4);
+	      /* This is masked minmax.  */
+	      if (TREE_CODE (args[3]) != INTEGER_CST
+		  || TREE_SIDE_EFFECTS (args[2]))
+		break;
+	      mask = TREE_INT_CST_LOW (args[3]);
+	      unsigned elems = TYPE_VECTOR_SUBPARTS (TREE_TYPE (args[0]));
+	      mask |= HOST_WIDE_INT_M1U << elems;
+	      if (mask != HOST_WIDE_INT_M1U
+		  && TREE_CODE (args[2]) != VECTOR_CST)
+		break;
+	      if (n_args >= 5)
+		{
+		  if (!tree_fits_uhwi_p (args[4]))
+		    break;
+		  if (tree_to_uhwi (args[4]) != 4
+		      && tree_to_uhwi (args[4]) != 8)
+		    break;
+		}
+	      if (mask == (HOST_WIDE_INT_M1U << elems))
+		return args[2];
+	    }
+	  /* Punt on NaNs, unless exceptions are disabled.  */
+	  if (HONOR_NANS (args[0])
+	      && (n_args < 5 || tree_to_uhwi (args[4]) != 8))
+	    for (int i = 0; i < 2; ++i)
+	      {
+		unsigned count = vector_cst_encoded_nelts (args[i]);
+		for (unsigned j = 0; j < count; ++j)
+		  if (tree_expr_nan_p (VECTOR_CST_ENCODED_ELT (args[i], j)))
+		    return NULL_TREE;
+	      }
+	  {
+	    tree res = const_binop (tcode,
+				    truth_type_for (TREE_TYPE (args[0])),
+				    args[0], args[1]);
+	    if (res == NULL_TREE || TREE_CODE (res) != VECTOR_CST)
+	      break;
+	    res = fold_ternary (VEC_COND_EXPR, TREE_TYPE (args[0]), res,
+				args[0], args[1]);
+	    if (res == NULL_TREE || TREE_CODE (res) != VECTOR_CST)
+	      break;
+	    if (mask != HOST_WIDE_INT_M1U)
+	      {
+		unsigned nelts = TYPE_VECTOR_SUBPARTS (TREE_TYPE (args[0]));
+		vec_perm_builder sel (nelts, nelts, 1);
+		for (unsigned int i = 0; i < nelts; i++)
+		  if (mask & (HOST_WIDE_INT_1U << i))
+		    sel.quick_push (i);
+		  else
+		    sel.quick_push (nelts + i);
+		vec_perm_indices indices (sel, 2, nelts);
+		res = fold_vec_perm (TREE_TYPE (args[0]), res, args[2],
+				     indices);
+		if (res == NULL_TREE || TREE_CODE (res) != VECTOR_CST)
+		  break;
+	      }
+	    if (is_scalar)
+	      {
+		unsigned nelts = TYPE_VECTOR_SUBPARTS (TREE_TYPE (args[0]));
+		vec_perm_builder sel (nelts, nelts, 1);
+		sel.quick_push (0);
+		for (unsigned int i = 1; i < nelts; i++)
+		  sel.quick_push (nelts + i);
+		vec_perm_indices indices (sel, 2, nelts);
+		res = fold_vec_perm (TREE_TYPE (args[0]), res, args[0],
+				     indices);
+		if (res == NULL_TREE || TREE_CODE (res) != VECTOR_CST)
+		  break;
+	      }
+	    return res;
+	  }
+
 	default:
 	  break;
 	}
@@ -19508,6 +19635,74 @@ ix86_gimple_fold_builtin (gimple_stmt_iterator *gsi)
       }
       return true;
 
+    case IX86_BUILTIN_MINPS:
+    case IX86_BUILTIN_MINPD:
+    case IX86_BUILTIN_MINPS256:
+    case IX86_BUILTIN_MINPD256:
+    case IX86_BUILTIN_MINPS512:
+    case IX86_BUILTIN_MINPD512:
+    case IX86_BUILTIN_MINPS128_MASK:
+    case IX86_BUILTIN_MINPD128_MASK:
+    case IX86_BUILTIN_MINPS256_MASK:
+    case IX86_BUILTIN_MINPD256_MASK:
+    case IX86_BUILTIN_MINPH128_MASK:
+    case IX86_BUILTIN_MINPH256_MASK:
+    case IX86_BUILTIN_MINPH512_MASK:
+      tcode = LT_EXPR;
+      goto do_minmax;
+
+    case IX86_BUILTIN_MAXPS:
+    case IX86_BUILTIN_MAXPD:
+    case IX86_BUILTIN_MAXPS256:
+    case IX86_BUILTIN_MAXPD256:
+    case IX86_BUILTIN_MAXPS512:
+    case IX86_BUILTIN_MAXPD512:
+    case IX86_BUILTIN_MAXPS128_MASK:
+    case IX86_BUILTIN_MAXPD128_MASK:
+    case IX86_BUILTIN_MAXPS256_MASK:
+    case IX86_BUILTIN_MAXPD256_MASK:
+    case IX86_BUILTIN_MAXPH128_MASK:
+    case IX86_BUILTIN_MAXPH256_MASK:
+    case IX86_BUILTIN_MAXPH512_MASK:
+      tcode = GT_EXPR;
+    do_minmax:
+      gcc_assert (n_args >= 2);
+      /* Without SSE4.1 we often aren't able to pattern match it back to the
+	 desired instruction.  */
+      if (!gimple_call_lhs (stmt) || !optimize || !TARGET_SSE4_1)
+	break;
+      arg0 = gimple_call_arg (stmt, 0);
+      arg1 = gimple_call_arg (stmt, 1);
+      elems = TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0));
+      /* For masked minmax, only optimize if the mask is all ones.  */
+      if (n_args > 2
+	  && !ix86_masked_all_ones (elems, gimple_call_arg (stmt, 3)))
+	break;
+      if (n_args >= 5)
+	{
+	  tree arg4 = gimple_call_arg (stmt, 4);
+	  if (!tree_fits_uhwi_p (arg4))
+	    break;
+	  if (tree_to_uhwi (arg4) == 4)
+	    /* Ok.  */;
+	  else if (tree_to_uhwi (arg4) != 8)
+	    /* Invalid round argument.  */
+	    break;
+	  else if (HONOR_NANS (arg0))
+	    /* Lowering to comparison would raise exceptions which
+	       shouldn't be raised.  */
+	    break;
+	}
+      {
+	tree type = truth_type_for (TREE_TYPE (arg0));
+	tree cmpres = gimple_build (&stmts, tcode, type, arg0, arg1);
+	gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
+	g = gimple_build_assign (gimple_call_lhs (stmt),
+				 VEC_COND_EXPR, cmpres, arg0, arg1);
+	gsi_replace (gsi, g, false);
+      }
+      return true;
+
     default:
       break;
     }
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-pr116738-1.c b/gcc/testsuite/gcc.target/i386/avx512f-pr116738-1.c
new file mode 100644
index 0000000..9b58614
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-pr116738-1.c
@@ -0,0 +1,56 @@
+/* PR target/116738 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -mavx512f -fdump-tree-optimized" } */
+/* { dg-final { scan-tree-dump-not "__builtin_ia32_min" "optimized" } } */
+/* { dg-final { scan-tree-dump-not "__builtin_ia32_max" "optimized" } } */
+
+#include <x86intrin.h>
+
+void
+test_pr116738 (void)
+{
+  __m512 a = _mm512_setr_ps (1.f, 2.f, 0.f, -0.f, -0.f, 0.f, 5.f, 6.f, 7.f,
+			     8.f, 9.f, 10.f, 11.f, -__builtin_inff (),
+			     __builtin_inff (), -42.f);
+  __m512 b = _mm512_setr_ps (-0.f, 3.f, -0.f, 0.f, -0.f, 0.f, 5.f, 5.f, 8.f,
+			     7.f, 10.f, -9.f, 12.f, 0.f, -0.f, 42.f);
+  __m512 w = _mm512_setr_ps (4.f, 5.f, 6.f, 7.f, 8.f, 9.f, 10.f, 0.f, 1.f,
+			     2.f, 3.f, 4.f, 5.f, 6.f, 7.f, 8.f);
+  __m512 c = _mm512_mask_min_ps (w, -1, a, b);
+  __m512 d = _mm512_mask_min_ps (w, 18658, a, b);
+  __m512 e = _mm512_mask_min_ps (w, 54649, a, b);
+  __m512 f = _mm512_mask_max_ps (w, -1, a, b);
+  __m512 g = _mm512_mask_max_ps (w, 18658, a, b);
+  __m512 h = _mm512_mask_max_ps (w, 54649, a, b);
+  __m128 i = _mm_setr_ps (1.f, 2.f, 0.f, -0.f);
+  __m128 j = _mm_setr_ps (-0.f, 3.f, -0.f, 0.f);
+  __m128 k = _mm_min_ss (i, j);
+  __m128 l = _mm_max_ss (j, i);
+  __m512 ce = _mm512_setr_ps (-0.f, 2.f, -0.f, 0.f, -0.f, 0.f, 5.f, 5.f, 7.f,
+			      7.f, 9.f, -9.f, 11.f, -__builtin_inff (),
+			      -0.f, -42.f);
+  __m512 de = _mm512_setr_ps (4.f, 2.f, 6.f, 7.f, 8.f, 0.f, 5.f, 5.f, 1.f,
+			      2.f, 3.f, -9.f, 5.f, 6.f, -0.f, 8.f); 
+  __m512 ee = _mm512_setr_ps (-0.f, 5.f, 6.f, 0.f, -0.f, 0.f, 5.f, 0.f, 7.f,
+			      2.f, 9.f, 4.f, 11.f, 6.f, -0.f, -42.f);
+  __m512 fe = _mm512_setr_ps (1.f, 3.f, -0.f, 0.f, -0.f, 0.f, 5.f, 6.f, 8.f,
+			      8.f, 10.f, 10.f, 12.f, 0.f, __builtin_inff (),
+			      42.f);
+  __m512 ge = _mm512_setr_ps (4.f, 3.f, 6.f, 7.f, 8.f, 0.f, 5.f, 6.f, 1.f,
+			      2.f, 3.f, 10.f, 5.f, 6.f, __builtin_inff (),
+			      8.f);
+  __m512 he = _mm512_setr_ps (1.f, 5.f, 6.f, 0.f, -0.f, 0.f, 5.f, 0.f, 8.f,
+			      2.f, 10.f, 4.f, 12.f, 6.f, __builtin_inff (),
+			      42.f);
+  __m128 ke = _mm_setr_ps (-0.f, 2.f, 0.f, -0.f);
+  __m128 le = _mm_setr_ps (1.f, 3.f, -0.f, 0.f);
+  if (__builtin_memcmp (&c, &ce, sizeof (c))
+      || __builtin_memcmp (&d, &de, sizeof (d))
+      || __builtin_memcmp (&e, &ee, sizeof (e))
+      || __builtin_memcmp (&f, &fe, sizeof (f))
+      || __builtin_memcmp (&g, &ge, sizeof (g))
+      || __builtin_memcmp (&h, &he, sizeof (h))
+      || __builtin_memcmp (&k, &ke, sizeof (k))
+      || __builtin_memcmp (&l, &le, sizeof (l)))
+    __builtin_abort ();
+}
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-pr116738-2.c b/gcc/testsuite/gcc.target/i386/avx512f-pr116738-2.c
new file mode 100644
index 0000000..8a429a2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-pr116738-2.c
@@ -0,0 +1,15 @@
+/* PR target/116738 */
+/* { dg-do run } */
+/* { dg-options "-O2 -mavx512f" } */
+/* { dg-require-effective-target avx512f } */
+
+#define AVX512F
+#include "avx512f-helper.h"
+
+#include "avx512f-pr116738-1.c"
+
+void
+TEST (void)
+{
+  test_pr116738 ();
+}