[PATCH] RISC-V: Implement ZTSO extension.

[shihua]

From: LiaoShihua <shi...@iscas.ac.cn>

      ZTSO is the extension of tatol store order model.
      This extension adds no new instructions to the ISA, and you can use it 
with arch "ztso".
      If you use it, TSO flag will be generate in the ELF header.

gcc/ChangeLog:

        * common/config/riscv/riscv-common.cc: define new arch.
        * config/riscv/riscv-opts.h (MASK_ZTSO): Ditto.
        (TARGET_ZTSO):Ditto.
        * config/riscv/riscv.opt:Ditto.

---
 gcc/common/config/riscv/riscv-common.cc | 4 +++-
 gcc/config/riscv/riscv-opts.h           | 3 +++
 gcc/config/riscv/riscv.opt              | 3 +++
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/common/config/riscv/riscv-common.cc 
b/gcc/common/config/riscv/riscv-common.cc
index a904893b9ed..f4730b991d7 100644
--- a/gcc/common/config/riscv/riscv-common.cc
+++ b/gcc/common/config/riscv/riscv-common.cc
@@ -185,6 +185,8 @@ static const struct riscv_ext_version 
riscv_ext_version_table[] =
   {"zvl32768b", ISA_SPEC_CLASS_NONE, 1, 0},
   {"zvl65536b", ISA_SPEC_CLASS_NONE, 1, 0},
 
+  {"ztso", ISA_SPEC_CLASS_NONE, 0, 1},
+
   /* Terminate the list.  */
   {NULL, ISA_SPEC_CLASS_NONE, 0, 0}
 };
@@ -1080,7 +1082,7 @@ static const riscv_ext_flag_table_t 
riscv_ext_flag_table[] =
   {"zvl32768b", &gcc_options::x_riscv_zvl_flags, MASK_ZVL32768B},
   {"zvl65536b", &gcc_options::x_riscv_zvl_flags, MASK_ZVL65536B},
 
-
+  {"ztso", &gcc_options::x_riscv_ztso_subext, MASK_ZTSO},
   {NULL, NULL, 0}
 };
 
diff --git a/gcc/config/riscv/riscv-opts.h b/gcc/config/riscv/riscv-opts.h
index 929e4e3a7c5..9cb5f2a550a 100644
--- a/gcc/config/riscv/riscv-opts.h
+++ b/gcc/config/riscv/riscv-opts.h
@@ -136,4 +136,7 @@ enum stack_protector_guard {
 #define TARGET_ZVL32768B ((riscv_zvl_flags & MASK_ZVL32768B) != 0)
 #define TARGET_ZVL65536B ((riscv_zvl_flags & MASK_ZVL65536B) != 0)
 
+#define MASK_ZTSO    (1 <<  0)
+#define TARGET_ZTSO    ((riscv_ztso_subext & MASK_ZTSO) != 0)
+
 #endif /* ! GCC_RISCV_OPTS_H */
diff --git a/gcc/config/riscv/riscv.opt b/gcc/config/riscv/riscv.opt
index 9fffc08220d..6128bfa31dc 100644
--- a/gcc/config/riscv/riscv.opt
+++ b/gcc/config/riscv/riscv.opt
@@ -209,6 +209,9 @@ int riscv_vector_eew_flags
 TargetVariable
 int riscv_zvl_flags
 
+TargetVariable
+int riscv_ztso_subext
+
 Enum
 Name(isa_spec_class) Type(enum riscv_isa_spec_class)
 Supported ISA specs (for use with the -misa-spec= option):
-- 
2.31.1.windows.1