RISC-V: Bugfix ICE for RVV intrinisc vfw on _Float16 scalar

For the vfw vx format RVV intrinsic, the scalar type _Float16 also
requires the zvfh extension.  Unfortunately,  we only check the
vector tree type and miss the scalar _Float16 type checking.  For
example:

vfloat32mf2_t test_vfwsub_wf_f32mf2(vfloat32mf2_t vs2, _Float16 rs1, size_t vl)
{
  return __riscv_vfwsub_wf_f32mf2(vs2, rs1, vl);
}

It should report some error message like zvfh extension is required
instead of ICE for unreg insn.

This patch would like to make up such kind of validation for _Float16
in the RVV intrinsic API.  It will report some error like below when
there is no zvfh enabled.

error: built-in function '__riscv_vfwsub_wf_f32mf2(vs2,  rs1,  vl)'
  requires the zvfhmin or zvfh ISA extension

Passed the rv64gcv fully regression tests, included c/c++/fortran.

	PR target/114988

gcc/ChangeLog:

	* config/riscv/riscv-vector-builtins.cc
	(validate_instance_type_required_extensions): New func impl to
	validate the intrinisc func type ops.
	(expand_builtin): Validate instance type before expand.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/base/pr114988-1.c: New test.
	* gcc.target/riscv/rvv/base/pr114988-2.c: New test.

Signed-off-by: Pan Li <pan2.li@intel.com>

3 files changed, 69 insertions, 0 deletions

diff --git a/gcc/config/riscv/riscv-vector-builtins.cc b/gcc/config/riscv/riscv-vector-builtins.cc
index 192a6c2..3fdb440 100644
--- a/gcc/config/riscv/riscv-vector-builtins.cc
+++ b/gcc/config/riscv/riscv-vector-builtins.cc
@@ -4632,6 +4632,54 @@ gimple_fold_builtin (unsigned int code, gimple_stmt_iterator *gsi, gcall *stmt)
   return gimple_folder (rfn.instance, rfn.decl, gsi, stmt).fold ();
 }
 
+static bool
+validate_instance_type_required_extensions (const rvv_type_info type,
+					    tree exp)
+{
+  uint64_t exts = type.required_extensions;
+
+  if ((exts & RVV_REQUIRE_ELEN_FP_16) &&
+    !TARGET_VECTOR_ELEN_FP_16_P (riscv_vector_elen_flags))
+    {
+      error_at (EXPR_LOCATION (exp),
+		"built-in function %qE requires the "
+		"zvfhmin or zvfh ISA extension",
+		exp);
+      return false;
+    }
+
+  if ((exts & RVV_REQUIRE_ELEN_FP_32) &&
+    !TARGET_VECTOR_ELEN_FP_32_P (riscv_vector_elen_flags))
+    {
+      error_at (EXPR_LOCATION (exp),
+		"built-in function %qE requires the "
+		"zve32f, zve64f, zve64d or v ISA extension",
+		exp);
+      return false;
+    }
+
+  if ((exts & RVV_REQUIRE_ELEN_FP_64) &&
+    !TARGET_VECTOR_ELEN_FP_64_P (riscv_vector_elen_flags))
+    {
+      error_at (EXPR_LOCATION (exp),
+		"built-in function %qE requires the zve64d or v ISA extension",
+		exp);
+      return false;
+    }
+
+  if ((exts & RVV_REQUIRE_ELEN_64) &&
+    !TARGET_VECTOR_ELEN_64_P (riscv_vector_elen_flags))
+    {
+      error_at (EXPR_LOCATION (exp),
+		"built-in function %qE requires the "
+		"zve64x, zve64f, zve64d or v ISA extension",
+		exp);
+      return false;
+    }
+
+  return true;
+}
+
 /* Expand a call to the RVV function with subcode CODE.  EXP is the call
    expression and TARGET is the preferred location for the result.
    Return the value of the lhs.  */
@@ -4649,6 +4697,9 @@ expand_builtin (unsigned int code, tree exp, rtx target)
       return target;
     }
 
+  if (!validate_instance_type_required_extensions (rfn.instance.type, exp))
+    return target;
+
   return function_expander (rfn.instance, rfn.decl, exp, target).expand ();
 }
 
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-1.c b/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-1.c
new file mode 100644
index 0000000..b847480
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-1.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d -O3" } */
+
+#include "riscv_vector.h"
+
+vfloat32mf2_t test_vfwsub_wf_f32mf2(vfloat32mf2_t vs2, _Float16 rs1, size_t vl)
+{
+  return __riscv_vfwsub_wf_f32mf2(vs2, rs1, vl); /* { dg-error {built-in function '__riscv_vfwsub_wf_f32mf2\(vs2,  rs1,  vl\)' requires the zvfhmin or zvfh ISA extension} } */
+}
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-2.c b/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-2.c
new file mode 100644
index 0000000..49aa314
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr114988-2.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d -O3" } */
+
+#include "riscv_vector.h"
+
+vfloat32mf2_t test_vfwadd_wf_f32mf2(vfloat32mf2_t vs2, _Float16 rs1, size_t vl)
+{
+  return __riscv_vfwadd_wf_f32mf2(vs2, rs1, vl); /* { dg-error {built-in function '__riscv_vfwadd_wf_f32mf2\(vs2,  rs1,  vl\)' requires the zvfhmin or zvfh ISA extension} } */
+}