368ddbcd4f
* lib/linux/arm-mes-gcc/crt1.c (_start): Replace manual initialization of __stdin, __stdout, __stderr, and environ with __init_io (). * lib/linux/arm-mes-m2/crt1.M1 (_start): Likewise. * lib/linux/arm-mes-mescc/crt1.c (_start): Likewise.
135 lines
4.7 KiB
Plaintext
135 lines
4.7 KiB
Plaintext
### GNU Mes --- Maxwell Equations of Software
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### Copyright (C) 2016 Jeremiah Orians
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### Copyright © 2022,2023 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
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###
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### This file is part of GNU Mes.
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###
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### GNU Mes is free software; you can redistribute it and/or modify it
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### 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 (at
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### your option) any later version.
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###
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### GNU Mes is distributed in the hope that it will be useful, but
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### 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 GNU Mes. If not, see <http://www.gnu.org/licenses/>.
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:_start
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'0' SP BP NO_SHIFT MOVE_ALWAYS ; Setup Base Pointer
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;; Prepare argv
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!4 R0 ADD BP ARITH_ALWAYS ; ARGV_address = BP + 4
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{R0} PUSH_ALWAYS ; Put argv on the stack
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;; Prepare envp
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'0' BP R0 NO_SHIFT MOVE_ALWAYS ; Address we need to load from
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!0 R0 LOAD32 R0 MEMORY ; Get ARGC
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!2 R0 ADD R0 ARITH_ALWAYS ; OFFSET = ARGC + 2
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'0' R0 R0 '1' MOVE_ALWAYS ; OFFSET = OFFSET * WORDSIZE
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'0' R0 R0 ADD BP ARITH2_ALWAYS ; ENVP_address = BP + OFFSET
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{R0} PUSH_ALWAYS ; Put envp on the stack
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;; Stack offset
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!4 BP ADD BP ARITH_ALWAYS ; Fix BP
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^~FUNCTION___init_io CALL_ALWAYS ; Init libc
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^~FUNCTION_main CALL_ALWAYS ; Jump right into main
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SYS_exit mov____$i8,%r7
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swi____$0
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# Unsigned Divide
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:divide
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{R4} PUSH_ALWAYS ; Protect R4
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{R3} PUSH_ALWAYS ; Protect R3
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{R2} PUSH_ALWAYS ; Protect R2
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'0' R0 R3 NO_SHIFT MOVE_ALWAYS ; MOV R3,R0
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'0' R1 R2 NO_SHIFT MOVE_ALWAYS ; MOV R2,R1
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!0 R0 LOADI8_ALWAYS ; MOV R0,#0
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!0 CMPI8 R2 IMM_ALWAYS ; CMP R2,#0
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!1 R0 SUB R0 ARITH_LT ; SUBLT R0,R0,#1
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!0 CMPI8 R3 IMM_ALWAYS ; CMP R3,#0
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!0 R3 RSUB R3 ARITH_LT ; RSBLT R3,R3,#0
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'0' R0 R0 MVN_LT ; MVNLT R0,R0
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'0' R0 R4 NO_SHIFT MOVE_ALWAYS ; MOV R4,R0
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!32 R0 LOADI8_ALWAYS ; MOV R0,#32.
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!0 R1 LOADI8_ALWAYS ; MOV R1,#0
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:divide_loop
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'0' R2 R2 ADDS R2 ARITH2_ALWAYS ; ADDS R2,R2,R2
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'0' R1 R1 ADCS R1 ARITH2_ALWAYS ; ADCS R1,R1,R1
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'0' R3 CMP R1 AUX_ALWAYS ; CMP R1,R3
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'0' R3 R1 SUB R1 ARITH2_GE ; SUBGE R1,R1,R3
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!1 R2 ADD R2 ARITH_GE ; ADDGE R2,R2,#1
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!1 R0 SUB R0 ARITH_ALWAYS ; SUB R0,R0,#1
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!0 CMPI8 R0 IMM_ALWAYS ; CMP R0,#0
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^~divide_loop JUMP_NE ; BNE loop
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'0' R2 R0 NO_SHIFT MOVE_ALWAYS ; MOV R0,R2
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{R2} POP_ALWAYS ; Restore R2
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{R3} POP_ALWAYS ; Restore R3
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{R4} POP_ALWAYS ; Restore R4
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'1' LR RETURN
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# Signed Divide
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:divides
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{R4} PUSH_ALWAYS ; Protect R4
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{R3} PUSH_ALWAYS ; Protect R3
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{R2} PUSH_ALWAYS ; Protect R2
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'0' R0 R3 NO_SHIFT MOVE_ALWAYS ; MOV R3,R0
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'0' R1 R2 NO_SHIFT MOVE_ALWAYS ; MOV R2,R1
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!0 R0 LOADI8_ALWAYS ; MOV R0,#0
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!0 CMPI8 R2 IMM_ALWAYS ; CMP R2,#0
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!0 R2 RSUB R2 ARITH_LT ; RSBLT R2,R2,#0
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!1 R0 SUB R0 ARITH_LT ; SUBLT R0,R0,#1
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!0 CMPI8 R3 IMM_ALWAYS ; CMP R3,#0
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!0 R3 RSUB R3 ARITH_LT ; RSBLT R3,R3,#0
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'0' R0 R0 MVN_LT ; MVNLT R0,R0
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'0' R0 R4 NO_SHIFT MOVE_ALWAYS ; MOV R4,R0
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!32 R0 LOADI8_ALWAYS ; MOV R0,#32.
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!0 R1 LOADI8_ALWAYS ; MOV R1,#0
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:divides_loop
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'0' R2 R2 ADDS R2 ARITH2_ALWAYS ; ADDS R2,R2,R2
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'0' R1 R1 ADCS R1 ARITH2_ALWAYS ; ADCS R1,R1,R1
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'0' R3 CMP R1 AUX_ALWAYS ; CMP R1,R3
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'0' R3 R1 SUB R1 ARITH2_GE ; SUBGE R1,R1,R3
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!1 R2 ADD R2 ARITH_GE ; ADDGE R2,R2,#1
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!1 R0 SUB R0 ARITH_ALWAYS ; SUB R0,R0,#1
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!0 CMPI8 R0 IMM_ALWAYS ; CMP R0,#0
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^~divides_loop JUMP_NE ; BNE loop
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!0 CMPI8 R4 IMM_ALWAYS ; CMP R4,#0
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!0 R2 RSUB R2 ARITH_NE ; RSBNE R2,R2,#0
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'0' R2 R0 NO_SHIFT MOVE_ALWAYS ; MOV R0,R2
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{R2} POP_ALWAYS ; Restore R2
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{R3} POP_ALWAYS ; Restore R3
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{R4} POP_ALWAYS ; Restore R4
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'1' LR RETURN
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# Unsigned Modulus
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:modulus
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{LR} PUSH_ALWAYS ; Prepare to leverage divide
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^~divide CALL_ALWAYS ; Use divide
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'0' R1 R0 NO_SHIFT MOVE_ALWAYS ; MOV R0,R1
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{LR} POP_ALWAYS ; Prepare for return
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'1' LR RETURN
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# Signed Modulus
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:moduluss
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{LR} PUSH_ALWAYS ; Prepare to leverage divide
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^~divides CALL_ALWAYS ; Use divides
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'0' R1 R0 NO_SHIFT MOVE_ALWAYS ; MOV R0,R1
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{LR} POP_ALWAYS ; Prepare for return
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'1' LR RETURN
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