[PATCH] RISCV:Create zmmul extension

[shihua@iscas.ac.cn]

From: Liaoshihua <shihua@iscas.ac.cn>

The Zmmul extension implements the multiplication subset of the M extension.I had added it in Gcc and Binutils.This patch is the realization of Zmmul.  
You can see them in https://github.com/Liaoshihua/riscv-binutils-gdb/tree/riscv-binutils-2.37-zmmul and https://github.com/Liaoshihua/riscv-gcc/tree/riscv-gcc-11.1.0-zmmul. The run results are in https://ci.rvperf.org/job/gnu-toolchain-zmmul-extension/. 

 bfd/elfxx-riscv.c      |  2 +-
 gas/config/tc-riscv.c  |  5 +++++
 include/opcode/riscv.h |  1 +
 opcodes/riscv-opc.c    | 10 +++++-----
 4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
index 39b69e2b0a..616c759487 100644
--- a/bfd/elfxx-riscv.c
+++ b/bfd/elfxx-riscv.c
@@ -1077,7 +1077,7 @@ static struct riscv_implicit_subset riscv_implicit_subsets[] =
 
 static const char * const riscv_std_z_ext_strtab[] =
 {
-  "zba", "zbb", "zbc", "zicsr", "zifencei", "zihintpause", NULL
+  "zba", "zbb", "zbc", "zicsr", "zifencei", "zihintpause", "zmmul", NULL
 };
 
 static const char * const riscv_std_s_ext_strtab[] =
diff --git a/gas/config/tc-riscv.c b/gas/config/tc-riscv.c
index 70cbc8190f..f904c6baa0 100644
--- a/gas/config/tc-riscv.c
+++ b/gas/config/tc-riscv.c
@@ -143,6 +143,8 @@ static const struct riscv_ext_version ext_version_table[] =
   {"zba",   ISA_SPEC_CLASS_DRAFT, 0, 93},
   {"zbc",   ISA_SPEC_CLASS_DRAFT, 0, 93},
 
+  {"zmmul",   ISA_SPEC_CLASS_DRAFT, 0, 1},  
+
   /* Terminate the list.  */
   {NULL, 0, 0, 0}
 };
@@ -343,6 +345,9 @@ riscv_multi_subset_supports (enum riscv_insn_class insn_class)
     case INSN_CLASS_ZBC:
       return riscv_subset_supports ("zbc");
 
+    case INSN_CLASS_ZMMUL:
+      return riscv_subset_supports ("zmmul");
+
     default:
       as_fatal ("internal: unreachable");
       return false;
diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h
index fdf3df4f5c..6b62f059ea 100644
--- a/include/opcode/riscv.h
+++ b/include/opcode/riscv.h
@@ -319,6 +319,7 @@ enum riscv_insn_class
   INSN_CLASS_ZBA,
   INSN_CLASS_ZBB,
   INSN_CLASS_ZBC,
+  INSN_CLASS_ZMMUL,
 };
 
 /* This structure holds information for a particular instruction.  */
diff --git a/opcodes/riscv-opc.c b/opcodes/riscv-opc.c
index f55a01b071..9781e400ca 100644
--- a/opcodes/riscv-opc.c
+++ b/opcodes/riscv-opc.c
@@ -489,15 +489,15 @@ const struct riscv_opcode riscv_opcodes[] =
 {"amominu.d.aqrl", 64, INSN_CLASS_A, "d,t,0(s)", MATCH_AMOMINU_D|MASK_AQRL, MASK_AMOMINU_D|MASK_AQRL, match_opcode, INSN_DREF|INSN_8_BYTE },
 
 /* Multiply/Divide instruction subset.  */
-{"mul",        0, INSN_CLASS_M,   "d,s,t",     MATCH_MUL, MASK_MUL, match_opcode, 0 },
-{"mulh",       0, INSN_CLASS_M,   "d,s,t",     MATCH_MULH, MASK_MULH, match_opcode, 0 },
-{"mulhu",      0, INSN_CLASS_M,   "d,s,t",     MATCH_MULHU, MASK_MULHU, match_opcode, 0 },
-{"mulhsu",     0, INSN_CLASS_M,   "d,s,t",     MATCH_MULHSU, MASK_MULHSU, match_opcode, 0 },
+{"mul",        0, INSN_CLASS_M || INSN_CLASS_ZMMUL,   "d,s,t",     MATCH_MUL, MASK_MUL, match_opcode, 0 },
+{"mulh",       0, INSN_CLASS_M || INSN_CLASS_ZMMUL,   "d,s,t",     MATCH_MULH, MASK_MULH, match_opcode, 0 },
+{"mulhu",      0, INSN_CLASS_M || INSN_CLASS_ZMMUL,   "d,s,t",     MATCH_MULHU, MASK_MULHU, match_opcode, 0 },
+{"mulhsu",     0, INSN_CLASS_M || INSN_CLASS_ZMMUL,   "d,s,t",     MATCH_MULHSU, MASK_MULHSU, match_opcode, 0 },
 {"div",        0, INSN_CLASS_M,   "d,s,t",     MATCH_DIV, MASK_DIV, match_opcode, 0 },
 {"divu",       0, INSN_CLASS_M,   "d,s,t",     MATCH_DIVU, MASK_DIVU, match_opcode, 0 },
 {"rem",        0, INSN_CLASS_M,   "d,s,t",     MATCH_REM, MASK_REM, match_opcode, 0 },
 {"remu",       0, INSN_CLASS_M,   "d,s,t",     MATCH_REMU, MASK_REMU, match_opcode, 0 },
-{"mulw",      64, INSN_CLASS_M,   "d,s,t",     MATCH_MULW, MASK_MULW, match_opcode, 0 },
+{"mulw",      64, INSN_CLASS_M || INSN_CLASS_ZMMUL,   "d,s,t",     MATCH_MULW, MASK_MULW, match_opcode, 0 },
 {"divw",      64, INSN_CLASS_M,   "d,s,t",     MATCH_DIVW, MASK_DIVW, match_opcode, 0 },
 {"divuw",     64, INSN_CLASS_M,   "d,s,t",     MATCH_DIVUW, MASK_DIVUW, match_opcode, 0 },
 {"remw",      64, INSN_CLASS_M,   "d,s,t",     MATCH_REMW, MASK_REMW, match_opcode, 0 },
-- 
2.31.1.windows.1