From 5653b767f0dd94cb0441dd326c4c2fb795b996c8 Mon Sep 17 00:00:00 2001 From: jjsuperpower Date: Sat, 17 Sep 2022 10:00:23 -0500 Subject: finished testing jump control --- hdl/core/jump_ctl.py | 180 ++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 157 insertions(+), 23 deletions(-) (limited to 'hdl/core') diff --git a/hdl/core/jump_ctl.py b/hdl/core/jump_ctl.py index 4dd037b..6a7cf1b 100644 --- a/hdl/core/jump_ctl.py +++ b/hdl/core/jump_ctl.py @@ -2,10 +2,11 @@ from amaranth import * from amaranth.sim import Simulator, Settle, Delay from enum import Enum, unique -from hdl.utils import cmd, step, sim +from hdl.utils import cmd, step, eval, sim, rand_bits_mix from hdl.lib.in_out_buff import InOutBuff # used for timing analysis -from hdl.core.alu import ALUFlags, ALU +from hdl.core.alu import ALUFlags, ALU, AluOpCodes #ALUOpCodes is for simulation only, not used in hardware +from hdl.config import NUM_RAND_TESTS @unique class JumpOpCodes(Enum): @@ -16,16 +17,17 @@ class JumpOpCodes(Enum): j_lt_s = 4 j_lte_s = 5 -class HDL(Elaboratable): +class JumpCtl(Elaboratable): def __init__(self, **kargs): self.alu_flags = Signal(ALU().alu_flags.width, reset_less=True) - self.jump_op = Signal(3, reset_less=True) + self.op = Signal(3, reset_less=True) + self.signed_bits = Signal(2, reset_less=True) - self.jump = Signal(reset_less=True) # true if jump condition is met + self.cond_true = Signal(reset_less=True) # true if jump condition is met - ports_in = [self.alu_flags, self.jump_op] - ports_out = [self.jump] + ports_in = [self.alu_flags, self.op, self.signed_bits] + ports_out = [self.cond_true] self.ports = {'in': ports_in, 'out': ports_out} self.sim = kargs["sim"] if "sim" in kargs else False @@ -38,36 +40,168 @@ class HDL(Elaboratable): dummy = Signal() m.d.sync += dummy.eq(~dummy) - with m.Switch(self.jump_op): + # xor the bits if both are positive or negative, this is needed to prevent problems with overflow + diff_sign = Signal(reset_less=True) + m.d.comb += diff_sign.eq(self.signed_bits.xor()) + + # checks conditions for ALU in1 and in2 + # e.g. in1 less than in2 + # this is done by in1 - in2 and reading the negative and zero flags + with m.Switch(self.op): with m.Case(JumpOpCodes.j_eq.value): - m.d.comb += self.jump.eq(self.alu_flags[ALUFlags.zero]) + m.d.comb += self.cond_true.eq(self.alu_flags[ALUFlags.zero.value]) + with m.Case(JumpOpCodes.j_ne.value): - m.d.comb += self.jump.eq(~self.alu_flags[ALUFlags.zero]) + m.d.comb += self.cond_true.eq(~self.alu_flags[ALUFlags.zero.value]) + with m.Case(JumpOpCodes.j_lt_u.value): - m.d.comb += self.jump.eq(self.alu_flags[ALUFlags.negative] & ~self.alu_flags[ALUFlags.zero]) + m.d.comb += self.cond_true.eq(self.alu_flags[ALUFlags.carry.value] & ~self.alu_flags[ALUFlags.zero.value]) + with m.Case(JumpOpCodes.j_lte_u.value): - m.d.comb += self.jump.eq(self.alu_flags[ALUFlags.negative] | self.alu_flags[ALUFlags.zero]) + m.d.comb += self.cond_true.eq(self.alu_flags[ALUFlags.carry.value] | self.alu_flags[ALUFlags.zero.value]) + with m.Case(JumpOpCodes.j_lt_s.value): - pass + with m.If(diff_sign): + m.d.comb += self.cond_true.eq(self.signed_bits[0] & ~self.alu_flags[ALUFlags.zero.value]) # signed bits are different, so use sign as condition to branch + with m.Else(): + m.d.comb += self.cond_true.eq(self.alu_flags[ALUFlags.negative.value] & ~self.alu_flags[ALUFlags.zero.value]) + with m.Case(JumpOpCodes.j_lte_s.value): - pass + with m.If(diff_sign): + m.d.comb += self.cond_true.eq(self.signed_bits[0] | self.alu_flags[ALUFlags.zero.value]) + with m.Else(): + m.d.comb += self.cond_true.eq(self.alu_flags[ALUFlags.negative.value] | self.alu_flags[ALUFlags.zero.value]) + with m.Case(): - m.d.comb += self.jump.eq(0) + m.d.comb += self.cond_true.eq(0) return m -# test addition -def test_hdl(): - dut = HDL(sim=True) +class DUT(Elaboratable): + def __init__(self, **kargs): # DUT will ONLY be used for simulation + self.alu = ALU(sim=True) + self.jump = JumpCtl(sim=True) + + def elaborate(self, platform=None): + m = Module() + m.submodules.alu = self.alu + m.submodules.jump = self.jump + + m.d.comb += self.jump.alu_flags.eq(self.alu.alu_flags) + m.d.comb += self.jump.signed_bits.eq(Cat(self.alu.in1[31], self.alu.in2[31])) + return m + +def _init_dut(dut): + yield dut.alu.in1.eq(0) + yield dut.alu.in2.eq(0) + yield dut.alu.op.eq(AluOpCodes.sub) + yield Settle() + + +# test jump if equal +def test_jump_eq(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) # sim=True is not needed, but I am trying to be consistent def proc(): - yield from step #step clock - yield Settle() #needed if for combinatorial logic - yield dut.something #read value + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_eq.value) + + for _ in range(tests): + in1 = rand_bits_mix(32) + in2 = rand_bits_mix(32) + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 == in2), f"jump_eq failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + sim(dut, proc) +# test jump if not equal +def test_jump_ne(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) + def proc(): + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_ne.value) + + for _ in range(tests): + in1 = rand_bits_mix(32) + in2 = rand_bits_mix(32) + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 != in2), f"jump_ne failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + + sim(dut, proc) + +# test jump if less than unsigned +def test_jump_lt_u(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) + def proc(): + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_lt_u.value) + + for _ in range(tests): + in1 = rand_bits_mix(32, sus='u') + in2 = rand_bits_mix(32, sus='u') + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 < in2), f"jump_lt_u failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + + sim(dut, proc) + +# test jump if less than or equal to unsigned +def test_jump_lte_u(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) + def proc(): + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_lte_u.value) + + for _ in range(tests): + in1 = rand_bits_mix(32, sus='u') + in2 = rand_bits_mix(32, sus='u') + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 <= in2), f"jump_lte_u failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + + sim(dut, proc) + +# test jump if less than signed +def test_jump_lt_s(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) + def proc(): + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_lt_s.value) + + for _ in range(tests): + in1 = rand_bits_mix(32, sus='s') + in2 = rand_bits_mix(32, sus='s') + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 < in2), f"jump_lt_s failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + + sim(dut, proc) + +# test jump if less than or equal to signed +def test_jump_lte_s(tests=NUM_RAND_TESTS): + dut = DUT(sim=True) + def proc(): + yield from _init_dut(dut) + yield dut.jump.op.eq(JumpOpCodes.j_lte_s.value) + + for _ in range(tests): + in1 = rand_bits_mix(32, sus='s') + in2 = rand_bits_mix(32, sus='s') + yield dut.alu.in1.eq(in1) + yield dut.alu.in2.eq(in2) + yield from eval() + assert (yield dut.jump.cond_true) == (in1 <= in2), f"jump_lte_s failed: in1={hex(in1)}, in2={hex(in2)}, cond_true={(yield dut.jump.cond_true)}" + + sim(dut, proc) if __name__ == '__main__': - hdl = InOutBuff(HDL()) - cmd(hdl) + hdl = JumpCtl() + cmd(hdl) \ No newline at end of file -- cgit v1.2.3