riscv64,exec,muldiv: add mulhsu

src/isa/riscv64/exec/all-instr.h

@@ -30,6 +30,7 @@ make_EHelper(priv);
 
 make_EHelper(mul);
 make_EHelper(mulh);
+make_EHelper(mulhsu);
 make_EHelper(mulhu);
 make_EHelper(div);
 make_EHelper(divu);
@@ -45,4 +46,4 @@ make_EHelper(remw);
 make_EHelper(divuw);
 make_EHelper(remuw);
 make_EHelper(sraw);
-make_EHelper(srlw);
\ No newline at end of file
+make_EHelper(srlw);

src/isa/riscv64/exec/exec.c

@@ -44,7 +44,7 @@ static OpcodeEntry op2_table [8] = {
 };
 
 static OpcodeEntry muldiv_table [8] = {
-  EX(mul), EX(mulh), EMPTY, EX(mulhu), EX(div), EX(divu), EX(rem), EX(remu)
+  EX(mul), EX(mulh), EX(mulhsu), EX(mulhu), EX(div), EX(divu), EX(rem), EX(remu)
 };
 
 static make_EHelper(op) {

src/isa/riscv64/exec/muldiv.c

@@ -21,6 +21,25 @@ make_EHelper(mulhu) {
   print_asm_template3(mulh);
 }
 
+make_EHelper(mulhsu) {
+  //rtl_msb(&s0, &id_src->val, 8);
+  //rtl_li(&s1, 0);
+  //rtl_sub(&s1, &s1, &id_src->val); // s1 = -id_src->val
+  //rtl_mux(&s1, &s0, &s1, &id_src->val); // s1 = |id_src->val|
+
+  //rtl_mul_hi(&id_dest->val, &s1, &id_src2->val);
+
+  //rtl_li(&s1, 0);
+  //rtl_sub(&s1, &s1, &id_dest->val); // s1 = -id_dest->val
+  //rtl_mux(&s0, &s0, &s1, &id_dest->val);
+
+  s0 = ((__int128_t)(sword_t)id_src->val * id_src2->val) >> 64;
+
+  rtl_sr(id_dest->reg, &s0, 4);
+
+  print_asm_template3(mulhsu);
+}
+
 make_EHelper(div) {
   rtl_idiv_q(&s0, &id_src->val, &id_src2->val);
   rtl_sr(id_dest->reg, &s0, 4);