RISCV: Add vector psabi checking.

gcc/config/riscv/riscv.cc

@@ -3728,6 +3728,98 @@ riscv_pass_fpr_pair (machine_mode mode, unsigned regno1,
 				   GEN_INT (offset2))));
 }
 
+/* Use the TYPE_SIZE to distinguish the type with vector_size attribute and
+   intrinsic vector type.  Because we can't get the decl for the params.  */
+
+static bool
+riscv_scalable_vector_type_p (const_tree type)
+{
+  tree size = TYPE_SIZE (type);
+  if (size && TREE_CODE (size) == INTEGER_CST)
+    return false;
+
+  /* For the data type like vint32m1_t, the size code is POLY_INT_CST.  */
+  return true;
+}
+
+static bool
+riscv_arg_has_vector (const_tree type)
+{
+  bool is_vector = false;
+
+  switch (TREE_CODE (type))
+    {
+    case RECORD_TYPE:
+      if (!COMPLETE_TYPE_P (type))
+	break;
+
+      for (tree f = TYPE_FIELDS (type); f; f = DECL_CHAIN (f))
+	if (TREE_CODE (f) == FIELD_DECL)
+	  {
+	    tree field_type = TREE_TYPE (f);
+	    if (!TYPE_P (field_type))
+	      break;
+
+	    /* Ignore it if it's fixed length vector.  */
+	    if (VECTOR_TYPE_P (field_type))
+	      is_vector = riscv_scalable_vector_type_p (field_type);
+	    else
+	      is_vector = riscv_arg_has_vector (field_type);
+	  }
+
+      break;
+
+    case VECTOR_TYPE:
+      is_vector = riscv_scalable_vector_type_p (type);
+      break;
+
+    default:
+      is_vector = false;
+      break;
+    }
+
+  return is_vector;
+}
+
+/* Pass the type to check whether it's a vector type or contains vector type.
+   Only check the value type and no checking for vector pointer type.  */
+
+static void
+riscv_pass_in_vector_p (const_tree type)
+{
+  static int warned = 0;
+
+  if (type && riscv_arg_has_vector (type) && !warned)
+    {
+      warning (OPT_Wpsabi, "ABI for the scalable vector type is currently in "
+	       "experimental stage and may changes in the upcoming version of "
+	       "GCC.");
+      warned = 1;
+    }
+}
+
+/* Initialize a variable CUM of type CUMULATIVE_ARGS
+   for a call to a function whose data type is FNTYPE.
+   For a library call, FNTYPE is 0.  */
+
+void
+init_cumulative_args (CUMULATIVE_ARGS *cum,  /* Argument info to initialize */
+		      tree fntype,	/* tree ptr for function decl */
+		      rtx libname,	/* SYMBOL_REF of library name or 0 */
+		      tree fndecl,
+		      int caller)
+{
+  memset (cum, 0, sizeof (*cum));
+
+  if (fndecl)
+    {
+      const tree_function_decl &fn = FUNCTION_DECL_CHECK (fndecl)->function_decl;
+
+      if (fn.built_in_class == NOT_BUILT_IN)
+	  cum->rvv_psabi_warning = 1;
+    }
+}
+
 /* Fill INFO with information about a single argument, and return an
    RTL pattern to pass or return the argument.  CUM is the cumulative
    state for earlier arguments.  MODE is the mode of this argument and
@@ -3812,6 +3904,12 @@ riscv_get_arg_info (struct riscv_arg_info *info, const CUMULATIVE_ARGS *cum,
 	}
     }
 
+  if (cum->rvv_psabi_warning)
+    {
+      /* Only check existing of vector type.  */
+      riscv_pass_in_vector_p (type);
+    }
+
   /* Work out the size of the argument.  */
   num_bytes = type ? int_size_in_bytes (type) : GET_MODE_SIZE (mode).to_constant ();
   num_words = (num_bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
@@ -3899,7 +3997,18 @@ riscv_function_value (const_tree type, const_tree func, machine_mode mode)
     }
 
   memset (&args, 0, sizeof args);
-  return riscv_get_arg_info (&info, &args, mode, type, true, true);
+
+  const_tree arg_type = type;
+  if (func && DECL_RESULT (func))
+    {
+      const tree_function_decl &fn = FUNCTION_DECL_CHECK(func)->function_decl;
+      if (fn.built_in_class == NOT_BUILT_IN)
+	args.rvv_psabi_warning = 1;
+
+      arg_type = TREE_TYPE (DECL_RESULT (func));
+    }
+
+  return riscv_get_arg_info (&info, &args, mode, arg_type, true, true);
 }
 
 /* Implement TARGET_PASS_BY_REFERENCE. */

gcc/config/riscv/riscv.h

@@ -671,14 +671,18 @@ typedef struct {
 
   /* Number of floating-point registers used so far, likewise.  */
   unsigned int num_fprs;
+
+  bool rvv_psabi_warning;
 } CUMULATIVE_ARGS;
 
 /* Initialize a variable CUM of type CUMULATIVE_ARGS
    for a call to a function whose data type is FNTYPE.
    For a library call, FNTYPE is 0.  */
 
+void init_cumulative_args (CUMULATIVE_ARGS *, tree, rtx, tree, int);
 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
-  memset (&(CUM), 0, sizeof (CUM))
+  init_cumulative_args (&(CUM), (FNTYPE), (LIBNAME), (INDIRECT), \
+			(N_NAMED_ARGS) != -1)
 
 #define EPILOGUE_USES(REGNO)	riscv_epilogue_uses (REGNO)
 

gcc/testsuite/gcc.target/riscv/vector-abi-1.c

@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O0 -march=rv64gcv -mabi=lp64d" } */
+
+#include "riscv_vector.h"
+
+void
+fun (vint32m1_t a) { } /* { dg-warning "the vector type" } */
+
+void
+bar ()
+{
+  vint32m1_t a;
+  fun (a);
+}

gcc/testsuite/gcc.target/riscv/vector-abi-2.c

@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d" } */
+
+#include "riscv_vector.h"
+
+vint32m1_t
+fun (vint32m1_t* a) {  return *a; }  /* { dg-warning "the vector type" } */
+
+void
+bar ()
+{
+  vint32m1_t a;
+  fun (&a);
+}

gcc/testsuite/gcc.target/riscv/vector-abi-3.c

@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d" } */
+
+#include "riscv_vector.h"
+
+vint32m1_t*
+fun (vint32m1_t* a) {  return a; }  /* { dg-bogus "the vector type" } */
+
+void
+bar ()
+{
+  vint32m1_t a;
+  fun (&a);
+}

gcc/testsuite/gcc.target/riscv/vector-abi-4.c

@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d" } */
+
+#include "riscv_vector.h"
+
+typedef int v4si __attribute__ ((vector_size (16)));
+
+v4si
+fun (v4si a) {  return a; }  /* { dg-bogus "the vector type" } */
+
+void
+bar ()
+{
+  v4si a;
+  fun (a);
+}

gcc/testsuite/gcc.target/riscv/vector-abi-5.c

@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d" } */
+
+typedef int v4si __attribute__ ((vector_size (16)));
+struct A { int a; v4si b; };
+
+void
+fun (struct A a) {} /* { dg-bogus "the vector type" } */
+
+void
+bar ()
+{
+  struct A a;
+  fun (a);
+}