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37 lines
1.4 KiB
Plaintext
37 lines
1.4 KiB
Plaintext
// Copyright Jamie Iles, 2017
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//
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// This file is part of s80x86.
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//
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// s80x86 is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// s80x86 is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with s80x86. If not, see <http://www.gnu.org/licenses/>.
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// BOUND
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.at 0x62;
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mar_write, mar_wr_sel EA, segment DS, jmp_rm_reg_mem bound_reg;
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.auto_address;
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bound_reg:
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b_sel IMMEDIATE, immediate 0x18, alu_op SELB, tmp_wr_en, jmp do_int;
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bound_mem:
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alu_op GETFLAGS, tmp_wr_en, segment DS, mem_read;
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a_sel MDR, b_sel RB, alu_op BOUNDL, update_flags CF;
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a_sel MAR, b_sel IMMEDIATE, immediate 0x2, alu_op ADD, mar_write,
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mar_wr_sel Q, segment DS, jmp_if_taken bound_fail;
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segment DS, mem_read;
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a_sel MDR, b_sel RB, alu_op BOUNDH, update_flags CF;
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jmp_if_taken bound_fail;
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b_sel TEMP, alu_op SELB, alu_op SETFLAGSB, update_flags CF, next_instruction;
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bound_fail:
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b_sel TEMP, alu_op SELB, alu_op SETFLAGSB, update_flags CF;
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b_sel IMMEDIATE, immediate 0x14, alu_op SELB, tmp_wr_en, jmp do_int;
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