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58 lines
1.7 KiB
Plaintext
58 lines
1.7 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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// LOOP
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.at 0xe2;
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ra_sel CX, jmp loop;
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.auto_address;
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loop:
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a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
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rd_sel_source MICROCODE_RD_SEL, rd_sel CX,
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rb_cl;
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jmp_rb_zero loop_not_taken;
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a_sel IP, b_sel IMMEDIATE, alu_op ADD, load_ip, next_instruction;
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loop_not_taken:
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next_instruction;
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// LOOPE
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.at 0xe1;
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ra_sel CX, jmp loope;
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.auto_address;
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loope:
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a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
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rd_sel_source MICROCODE_RD_SEL, rd_sel CX, rb_cl,
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jmp_if_zero loope_maybe_taken;
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jmp loop_not_taken;
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loope_maybe_taken:
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jmp_rb_zero loop_not_taken;
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a_sel IP, b_sel IMMEDIATE, alu_op ADD, load_ip, next_instruction;
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// LOOPNE
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.at 0xe0;
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ra_sel CX, jmp loopne;
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.auto_address;
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loopne:
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a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op SUB,
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rd_sel_source MICROCODE_RD_SEL, rd_sel CX, rb_cl,
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jmp_if_zero loop_not_taken;
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jmp_rb_zero loop_not_taken;
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loopne_taken:
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a_sel IP, b_sel IMMEDIATE, alu_op ADD, load_ip, next_instruction;
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