DBT-RISE-TGC/riscv/gen_input/RV32M.core_desc

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import "RV32IBase.core_desc"
InsructionSet RV32M extends RV32IBase {
constants {
MAXLEN:=128
}
instructions{
MUL{
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b000 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
val res[MAXLEN] <= zext(X[rs1], MAXLEN) * zext(X[rs2], MAXLEN);
X[rd]<= zext(res , XLEN);
}
}
MULH {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b001 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
val res[MAXLEN] <= sext(X[rs1], MAXLEN) * sext(X[rs2], MAXLEN);
X[rd]<= zext(res >> XLEN, XLEN);
}
}
MULHSU {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b010 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
val res[MAXLEN] <= sext(X[rs1], MAXLEN) * zext(X[rs2], MAXLEN);
X[rd]<= zext(res >> XLEN, XLEN);
}
}
MULHU {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b011 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
val res[MAXLEN] <= zext(X[rs1], MAXLEN) * zext(X[rs2], MAXLEN);
X[rd]<= zext(res >> XLEN, XLEN);
}
}
DIV {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b100 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0){
val M1[XLEN] <= -1;
val XLM1[8] <= XLEN-1;
val ONE[XLEN] <= 1;
val MMIN[XLEN] <= ONE<<XLM1;
if(X[rs1]==MMIN && X[rs2]==M1)
X[rd] <= MMIN;
else
X[rd] <= X[rs1]s / X[rs2]s;
}else
X[rd] <= -1;
}
}
DIVU {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b101 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0)
X[rd] <= X[rs1] / X[rs2];
else
X[rd] <= -1;
}
}
REM {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b110 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0) {
val M1[XLEN] <= -1; // constant -1
val XLM1[32] <= XLEN-1;
val ONE[XLEN] <= 1;
val MMIN[XLEN] <= ONE<<XLM1; // -2^(XLEN-1)
if(X[rs1]==MMIN && X[rs2]==M1)
X[rd] <= 0;
else
X[rd] <= X[rs1]'s % X[rs2]'s;
} else
X[rd] <= X[rs1];
}
}
REMU {
encoding: b0000001 | rs2[4:0] | rs1[4:0] | b111 | rd[4:0] | b0110011;
args_disass:"{name(rd)}, {name(rs1)}, {name(rs2)}";
if(rd != 0){
if(X[rs2]!=0)
X[rd] <= X[rs1] % X[rs2];
else
X[rd] <= X[rs1];
}
}
}
}