24 lines
1.1 KiB
Python
24 lines
1.1 KiB
Python
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from insn_R import *
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class rvfi_insn_sra(rvfi_insn_R):
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def __init__(self):
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super(rvfi_insn_sra, self).__init__()
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def ports(self):
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return super(rvfi_insn_sra, self).ports()
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def elaborate(self, platform):
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m = super(rvfi_insn_sra, self).elaborate(platform)
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# SRA instruction
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shamt = Signal(6)
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m.d.comb += shamt.eq(self.rvfi_rs2_rdata[:5])
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result = Signal(32)
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m.d.comb += result.eq((self.rvfi_rs1_rdata >> shamt) | (-(self.rvfi_rs1_rdata < 0) << (32 - shamt))) # https://stackoverflow.com/a/25207042
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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))
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m.d.comb += self.spec_rs1_addr.eq(self.insn_rs1)
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m.d.comb += self.spec_rs2_addr.eq(self.insn_rs2)
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m.d.comb += self.spec_rd_addr.eq(self.insn_rd)
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m.d.comb += self.spec_rd_wdata.eq(Mux(self.spec_rd_addr, result, 0))
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m.d.comb += self.spec_pc_wdata.eq(self.rvfi_pc_rdata + 4)
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return m
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