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64 lines
3.7 KiB
Plaintext
64 lines
3.7 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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#define SHIFT1(alu_func, flags) \
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.auto_address; \
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alu_func ## d0_d1_reg: \
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a_sel RA, b_sel IMMEDIATE, immediate 0x1, alu_op alu_func, \
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rd_sel_source MODRM_RM_REG, update_flags flags, \
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width WAUTO, next_instruction; \
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alu_func ## d0_d1_mem: \
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segment DS, mem_read, width WAUTO; \
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width WAUTO, a_sel MDR, b_sel IMMEDIATE, immediate 0x1, alu_op alu_func, \
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mdr_write, update_flags flags, segment DS, jmp write_complete;
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// Variable shifts first write the number of shifts into the temporary
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// register, then when processing, the ALU will perform a subtraction of the
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// count (which is an input to the ALU), and output the decremented value
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// along with a single bit-shifted value, stalling until complete. The
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// temporary register needs to be written each cycle, as does the result.
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#define SHIFTN(alu_func, flags) \
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alu_func ## d2_d3: \
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ra_modrm_rm_reg, b_sel RB, alu_op SELB, tmp_wr_en, width WAUTO, \
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segment DS, jmp_rm_reg_mem alu_func ## d2_d3_reg; \
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alu_func ## d2_d3_reg: \
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a_sel RA, b_sel RB, alu_op alu_func, rd_sel_source MODRM_RM_REG, \
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update_flags flags, width WAUTO, tmp_wr_sel Q_HIGH, \
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tmp_wr_en, next_instruction, ra_modrm_rm_reg; \
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alu_func ## d2_d3_mem: \
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segment DS, mem_read, width WAUTO, rb_cl; \
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width WAUTO, a_sel MDR, b_sel RB, alu_op alu_func, mdr_write, \
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update_flags flags, segment DS, tmp_wr_sel Q_HIGH, tmp_wr_en, \
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jmp write_complete;
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#define SHIFTN_IMM8(alu_func, flags) \
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alu_func ## c0_reg: \
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a_sel RA, b_sel IMMEDIATE, alu_op alu_func, rd_sel_source MODRM_RM_REG, \
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update_flags flags, width WAUTO, tmp_wr_sel Q_HIGH, \
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tmp_wr_en, next_instruction, ra_modrm_rm_reg; \
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alu_func ## c0_mem: \
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segment DS, mem_read, width WAUTO; \
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width WAUTO, a_sel MDR, b_sel IMMEDIATE, alu_op alu_func, mdr_write, \
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update_flags flags, segment DS, tmp_wr_sel Q_HIGH, tmp_wr_en, \
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jmp write_complete;
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#define SHIFTN_IMM16(alu_func, flags) \
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alu_func ## c1: \
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tmp_wr_en, alu_op SELB, b_sel IMMEDIATE, ra_modrm_rm_reg, segment DS, \
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jmp_rm_reg_mem alu_func ## c0_reg;
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