[PATCH v1] RISC-V: Support RVV VFMSUB rounding mode intrinsic API

[pan2.li@intel.com]

From: Pan Li <pan2.li@intel.com>

This patch would like to support the rounding mode API for the
VFMSUB as the below samples.

* __riscv_vfmsub_vv_f32m1_rm
* __riscv_vfmsub_vv_f32m1_rm_m
* __riscv_vfmsub_vf_f32m1_rm
* __riscv_vfmsub_vf_f32m1_rm_m

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

gcc/ChangeLog:

	* config/riscv/riscv-vector-builtins-bases.cc
	(class vfmsub_frm): New class for vfmsub frm.
	(vfmsub_frm): New declaration.
	(BASE): Ditto.
	* config/riscv/riscv-vector-builtins-bases.h: Ditto.
	* config/riscv/riscv-vector-builtins-functions.def
	(vfmsub_frm): New function declaration.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/base/float-point-msub.c: New test.
---
 .../riscv/riscv-vector-builtins-bases.cc      | 25 ++++++++++
 .../riscv/riscv-vector-builtins-bases.h       |  1 +
 .../riscv/riscv-vector-builtins-functions.def |  2 +
 .../riscv/rvv/base/float-point-msub.c         | 47 +++++++++++++++++++
 4 files changed, 75 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/float-point-msub.c

diff --git a/gcc/config/riscv/riscv-vector-builtins-bases.cc b/gcc/config/riscv/riscv-vector-builtins-bases.cc
index b085ba4f52d..381bc72c784 100644
--- a/gcc/config/riscv/riscv-vector-builtins-bases.cc
+++ b/gcc/config/riscv/riscv-vector-builtins-bases.cc
@@ -493,6 +493,29 @@ public:
   }
 };
 
+/* Implements below instructions for frm
+   - vfmsub
+*/
+class vfmsub_frm : public function_base
+{
+public:
+  bool has_rounding_mode_operand_p () const override { return true; }
+
+  bool has_merge_operand_p () const override { return false; }
+
+  rtx expand (function_expander &e) const override
+  {
+    if (e.op_info->op == OP_TYPE_vf)
+      return e.use_ternop_insn (
+	false, code_for_pred_mul_scalar (MINUS, e.vector_mode ()));
+    if (e.op_info->op == OP_TYPE_vv)
+      return e.use_ternop_insn (
+	false, code_for_pred_mul (MINUS, e.vector_mode ()));
+
+    gcc_unreachable ();
+  }
+};
+
 /* Implements vrsub.  */
 class vrsub : public function_base
 {
@@ -2266,6 +2289,7 @@ static CONSTEXPR const vfmsac_frm vfmsac_frm_obj;
 static CONSTEXPR const vfnmadd vfnmadd_obj;
 static CONSTEXPR const vfnmadd_frm vfnmadd_frm_obj;
 static CONSTEXPR const vfmsub vfmsub_obj;
+static CONSTEXPR const vfmsub_frm vfmsub_frm_obj;
 static CONSTEXPR const vfwmacc vfwmacc_obj;
 static CONSTEXPR const vfwnmacc vfwnmacc_obj;
 static CONSTEXPR const vfwmsac vfwmsac_obj;
@@ -2507,6 +2531,7 @@ BASE (vfmsac_frm)
 BASE (vfnmadd)
 BASE (vfnmadd_frm)
 BASE (vfmsub)
+BASE (vfmsub_frm)
 BASE (vfwmacc)
 BASE (vfwnmacc)
 BASE (vfwmsac)
diff --git a/gcc/config/riscv/riscv-vector-builtins-bases.h b/gcc/config/riscv/riscv-vector-builtins-bases.h
index 4ade0ace7b2..99cfbfd78c8 100644
--- a/gcc/config/riscv/riscv-vector-builtins-bases.h
+++ b/gcc/config/riscv/riscv-vector-builtins-bases.h
@@ -173,6 +173,7 @@ extern const function_base *const vfmsac_frm;
 extern const function_base *const vfnmadd;
 extern const function_base *const vfnmadd_frm;
 extern const function_base *const vfmsub;
+extern const function_base *const vfmsub_frm;
 extern const function_base *const vfwmacc;
 extern const function_base *const vfwnmacc;
 extern const function_base *const vfwmsac;
diff --git a/gcc/config/riscv/riscv-vector-builtins-functions.def b/gcc/config/riscv/riscv-vector-builtins-functions.def
index e9b16f99180..75235ec01d3 100644
--- a/gcc/config/riscv/riscv-vector-builtins-functions.def
+++ b/gcc/config/riscv/riscv-vector-builtins-functions.def
@@ -361,6 +361,8 @@ DEF_RVV_FUNCTION (vfmadd_frm, alu_frm, full_preds, f_vvvv_ops)
 DEF_RVV_FUNCTION (vfmadd_frm, alu_frm, full_preds, f_vvfv_ops)
 DEF_RVV_FUNCTION (vfnmadd_frm, alu_frm, full_preds, f_vvvv_ops)
 DEF_RVV_FUNCTION (vfnmadd_frm, alu_frm, full_preds, f_vvfv_ops)
+DEF_RVV_FUNCTION (vfmsub_frm, alu_frm, full_preds, f_vvvv_ops)
+DEF_RVV_FUNCTION (vfmsub_frm, alu_frm, full_preds, f_vvfv_ops)
 
 // 13.7. Vector Widening Floating-Point Fused Multiply-Add Instructions
 DEF_RVV_FUNCTION (vfwmacc, alu, full_preds, f_wwvv_ops)
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/float-point-msub.c b/gcc/testsuite/gcc.target/riscv/rvv/base/float-point-msub.c
new file mode 100644
index 00000000000..e58519d0742
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/float-point-msub.c
@@ -0,0 +1,47 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64 -O3 -Wno-psabi" } */
+
+#include "riscv_vector.h"
+
+typedef float float32_t;
+
+vfloat32m1_t
+test_riscv_vfmsub_vv_f32m1_rm (vfloat32m1_t vd, vfloat32m1_t op1,
+			       vfloat32m1_t op2, size_t vl) {
+  return __riscv_vfmsub_vv_f32m1_rm (vd, op1, op2, 0, vl);
+}
+
+vfloat32m1_t
+test_vfmsub_vv_f32m1_rm_m (vbool32_t mask, vfloat32m1_t vd, vfloat32m1_t op1,
+			   vfloat32m1_t op2, size_t vl) {
+  return __riscv_vfmsub_vv_f32m1_rm_m (mask, vd, op1, op2, 1, vl);
+}
+
+vfloat32m1_t
+test_vfmsub_vf_f32m1_rm (vfloat32m1_t vd, float32_t op1, vfloat32m1_t op2,
+			 size_t vl) {
+  return __riscv_vfmsub_vf_f32m1_rm (vd, op1, op2, 2, vl);
+}
+
+vfloat32m1_t
+test_vfmsub_vf_f32m1_rm_m (vfloat32m1_t vd, vbool32_t mask, float32_t op1,
+			   vfloat32m1_t op2, size_t vl) {
+  return __riscv_vfmsub_vf_f32m1_rm_m (mask, vd, op1, op2, 3, vl);
+}
+
+vfloat32m1_t
+test_riscv_vfmsub_vv_f32m1 (vfloat32m1_t vd, vfloat32m1_t op1,
+			    vfloat32m1_t op2, size_t vl) {
+  return __riscv_vfmsub_vv_f32m1 (vd, op1, op2, vl);
+}
+
+vfloat32m1_t
+test_vfmsub_vv_f32m1_m (vbool32_t mask, vfloat32m1_t vd, vfloat32m1_t op1,
+			vfloat32m1_t op2, size_t vl) {
+  return __riscv_vfmsub_vv_f32m1_m (mask, vd, op1, op2, vl);
+}
+
+/* { dg-final { scan-assembler-times {vfmsub\.v[vf]\s+v[0-9]+,\s*[fav]+[0-9]+,\s*v[0-9]+} 6 } } */
+/* { dg-final { scan-assembler-times {frrm\s+[axs][0-9]+} 4 } } */
+/* { dg-final { scan-assembler-times {fsrm\s+[axs][0-9]+} 4 } } */
+/* { dg-final { scan-assembler-times {fsrmi\s+[01234]} 4 } } */
-- 
2.34.1