[PATCH 1/2] RISC-V: Add arch flags for T-HEAD.

[Jojo R <rjiejie@linux.alibaba.com>]

	gcc/
	* gcc/config/riscv/riscv.opt (riscv_x_subext): New.
	* gcc/config/riscv/riscv-opts.h (MASK_XTHEAD_C): New.
	(TARGET_XTHEAD_C): Likewise.
	* gcc/common/config/riscv/riscv-common.c
	(riscv_ext_flag_table): Use riscv_x_subext & MASK_XTHEAD_C.
---
 gcc/common/config/riscv/riscv-common.c | 2 ++
 gcc/config/riscv/riscv-opts.h          | 3 +++
 gcc/config/riscv/riscv.opt             | 3 +++
 3 files changed, 8 insertions(+)

diff --git a/gcc/common/config/riscv/riscv-common.c b/gcc/common/config/riscv/riscv-common.c
index 10868fd417dc..a62080129259 100644
--- a/gcc/common/config/riscv/riscv-common.c
+++ b/gcc/common/config/riscv/riscv-common.c
@@ -906,6 +906,8 @@ static const riscv_ext_flag_table_t riscv_ext_flag_table[] =
   {"zicsr",    &gcc_options::x_riscv_zi_subext, MASK_ZICSR},
   {"zifencei", &gcc_options::x_riscv_zi_subext, MASK_ZIFENCEI},
 
+  {"xtheadc", &gcc_options::x_riscv_x_subext, MASK_XTHEAD_C},
+
   {NULL, NULL, 0}
 };
 
diff --git a/gcc/config/riscv/riscv-opts.h b/gcc/config/riscv/riscv-opts.h
index f4cf6ca4b823..a2d84a66f037 100644
--- a/gcc/config/riscv/riscv-opts.h
+++ b/gcc/config/riscv/riscv-opts.h
@@ -73,4 +73,7 @@ enum stack_protector_guard {
 #define TARGET_ZICSR    ((riscv_zi_subext & MASK_ZICSR) != 0)
 #define TARGET_ZIFENCEI ((riscv_zi_subext & MASK_ZIFENCEI) != 0)
 
+#define MASK_XTHEAD_C (1 << 0)
+#define TARGET_XTHEAD_C ((riscv_x_subext & MASK_XTHEAD_C) != 0)
+
 #endif /* ! GCC_RISCV_OPTS_H */
diff --git a/gcc/config/riscv/riscv.opt b/gcc/config/riscv/riscv.opt
index 5ff85c214307..84176aea05e9 100644
--- a/gcc/config/riscv/riscv.opt
+++ b/gcc/config/riscv/riscv.opt
@@ -195,6 +195,9 @@ long riscv_stack_protector_guard_offset = 0
 TargetVariable
 int riscv_zi_subext
 
+TargetVariable
+int riscv_x_subext
+
 Enum
 Name(isa_spec_class) Type(enum riscv_isa_spec_class)
 Supported ISA specs (for use with the -misa-spec= option):
-- 
2.24.3 (Apple Git-128)