RISC-V: Add ZVFH extension to the -march= option

This patch would like to add new sub extension (aka ZVFH) to the -march= option.
To make it simple, only the sub extension itself is involved in this patch, and
the underlying FP16 related RVV intrinsic API depends on the TARGET_ZVFH.

The Zvfh extension depends on the Zve32f and Zfhmin extensions. You can locate
more information about ZVFH from below spec doc.

https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#185-zvfh-vector-extension-for-half-precision-floating-point

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

gcc/ChangeLog:

	* common/config/riscv/riscv-common.cc:
	(riscv_implied_info): Add zvfh item.
	(riscv_ext_version_table): Ditto.
	(riscv_ext_flag_table): Ditto.
	* config/riscv/riscv-opts.h (MASK_ZVFH): New macro.
	(TARGET_ZVFH): Ditto.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/arch-21.c: New test.
	* gcc.target/riscv/predef-27.c: New test.

4 files changed, 66 insertions, 0 deletions

diff --git a/gcc/common/config/riscv/riscv-common.cc b/gcc/common/config/riscv/riscv-common.cc
index 92edafb..e6ed3df 100644
--- a/gcc/common/config/riscv/riscv-common.cc
+++ b/gcc/common/config/riscv/riscv-common.cc
@@ -105,6 +105,8 @@ static const riscv_implied_info_t riscv_implied_info[] =
   {"zfh", "zfhmin"},
   {"zfhmin", "f"},
   {"zvfhmin", "zve32f"},
+  {"zvfh", "zve32f"},
+  {"zvfh", "zfhmin"},
 
   {"zhinx", "zhinxmin"},
   {"zhinxmin", "zfinx"},
@@ -218,6 +220,7 @@ static const struct riscv_ext_version riscv_ext_version_table[] =
   {"zfh",       ISA_SPEC_CLASS_NONE, 1, 0},
   {"zfhmin",    ISA_SPEC_CLASS_NONE, 1, 0},
   {"zvfhmin",   ISA_SPEC_CLASS_NONE, 1, 0},
+  {"zvfh",      ISA_SPEC_CLASS_NONE, 1, 0},
 
   {"zmmul", ISA_SPEC_CLASS_NONE, 1, 0},
 
@@ -1262,6 +1265,7 @@ static const riscv_ext_flag_table_t riscv_ext_flag_table[] =
   {"zfhmin",    &gcc_options::x_riscv_zf_subext, MASK_ZFHMIN},
   {"zfh",       &gcc_options::x_riscv_zf_subext, MASK_ZFH},
   {"zvfhmin",   &gcc_options::x_riscv_zf_subext, MASK_ZVFHMIN},
+  {"zvfh",      &gcc_options::x_riscv_zf_subext, MASK_ZVFH},
 
   {"zmmul", &gcc_options::x_riscv_zm_subext, MASK_ZMMUL},
 
diff --git a/gcc/config/riscv/riscv-opts.h b/gcc/config/riscv/riscv-opts.h
index f34ca99..5f387d0 100644
--- a/gcc/config/riscv/riscv-opts.h
+++ b/gcc/config/riscv/riscv-opts.h
@@ -201,10 +201,12 @@ enum riscv_entity
 #define MASK_ZFHMIN   (1 << 0)
 #define MASK_ZFH      (1 << 1)
 #define MASK_ZVFHMIN  (1 << 2)
+#define MASK_ZVFH     (1 << 3)
 
 #define TARGET_ZFHMIN  ((riscv_zf_subext & MASK_ZFHMIN) != 0)
 #define TARGET_ZFH     ((riscv_zf_subext & MASK_ZFH) != 0)
 #define TARGET_ZVFHMIN ((riscv_zf_subext & MASK_ZVFHMIN) != 0)
+#define TARGET_ZVFH    ((riscv_zf_subext & MASK_ZVFH) != 0)
 
 #define MASK_ZMMUL      (1 << 0)
 #define TARGET_ZMMUL    ((riscv_zm_subext & MASK_ZMMUL) != 0)
diff --git a/gcc/testsuite/gcc.target/riscv/arch-21.c b/gcc/testsuite/gcc.target/riscv/arch-21.c
new file mode 100644
index 0000000..8a239a9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/arch-21.c
@@ -0,0 +1,5 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=rv32gcv_zvfh -mabi=ilp32 -mcmodel=medlow" } */
+int foo()
+{
+}
diff --git a/gcc/testsuite/gcc.target/riscv/predef-27.c b/gcc/testsuite/gcc.target/riscv/predef-27.c
new file mode 100644
index 0000000..0f9ab44
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-27.c
@@ -0,0 +1,55 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=rv64i_zvfh -mabi=lp64f -mcmodel=medlow -misa-spec=20191213" } */
+
+int main () {
+
+#ifndef __riscv_arch_test
+#error "__riscv_arch_test"
+#endif
+
+#if __riscv_xlen != 64
+#error "__riscv_xlen"
+#endif
+
+#if !defined(__riscv_i)
+#error "__riscv_i"
+#endif
+
+#if !defined(__riscv_f)
+#error "__riscv_f"
+#endif
+
+#if !defined(__riscv_zvfh)
+#error "__riscv_zvfh"
+#endif
+
+#if !defined(__riscv_zfhmin)
+#error "__riscv_zfhmin"
+#endif
+
+#if defined(__riscv_zvfhmin)
+#error "__riscv_zvfhmin"
+#endif
+
+#if defined(__riscv_v)
+#error "__riscv_v"
+#endif
+
+#if defined(__riscv_d)
+#error "__riscv_d"
+#endif
+
+#if defined(__riscv_c)
+#error "__riscv_c"
+#endif
+
+#if defined(__riscv_a)
+#error "__riscv_a"
+#endif
+
+#if defined(__riscv_zfh)
+#error "__riscv_zfh"
+#endif
+
+  return 0;
+}