From a3a9592c194896b47e28203e10ee3568ffb49144 Mon Sep 17 00:00:00 2001 From: Donald Sebastian Leung Date: Tue, 4 Aug 2020 12:47:35 +0800 Subject: [PATCH] Add SRA instruction --- insns/insn_sra.py | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 insns/insn_sra.py diff --git a/insns/insn_sra.py b/insns/insn_sra.py new file mode 100644 index 0000000..c3075d9 --- /dev/null +++ b/insns/insn_sra.py @@ -0,0 +1,23 @@ +from insn_R import * + +class rvfi_insn_sra(rvfi_insn_R): + def __init__(self): + super(rvfi_insn_sra, self).__init__() + def ports(self): + return super(rvfi_insn_sra, self).ports() + def elaborate(self, platform): + m = super(rvfi_insn_sra, self).elaborate(platform) + + # SRA instruction + shamt = Signal(6) + m.d.comb += shamt.eq(self.rvfi_rs2_rdata[:5]) + result = Signal(32) + m.d.comb += result.eq((self.rvfi_rs1_rdata >> shamt) | (-(self.rvfi_rs1_rdata < 0) << (32 - shamt))) # https://stackoverflow.com/a/25207042 + m.d.comb += self.spec_valid.eq(self.rvfi_valid & (~self.insn_padding) & (self.insn_funct7 == 0b0100000) & (self.insn_funct3 == 0b101) & (self.insn_opcode == 0b0110011)) + m.d.comb += self.spec_rs1_addr.eq(self.insn_rs1) + m.d.comb += self.spec_rs2_addr.eq(self.insn_rs2) + m.d.comb += self.spec_rd_addr.eq(self.insn_rd) + m.d.comb += self.spec_rd_wdata.eq(Mux(self.spec_rd_addr, result, 0)) + m.d.comb += self.spec_pc_wdata.eq(self.rvfi_pc_rdata + 4) + + return m