mirror of https://github.com/YosysHQ/picorv32.git
86 lines
1.3 KiB
ArmAsm
86 lines
1.3 KiB
ArmAsm
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.section .text
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.global _start
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.global _pvstart
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.global _data
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.global _data_lma
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_pvstart:
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/* zero-initialize all registers */
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addi x1, zero, 0
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addi x2, zero, 0
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addi x3, zero, 0
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addi x4, zero, 0
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addi x5, zero, 0
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addi x6, zero, 0
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addi x7, zero, 0
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addi x8, zero, 0
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addi x9, zero, 0
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addi x10, zero, 0
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addi x11, zero, 0
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addi x12, zero, 0
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addi x13, zero, 0
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addi x14, zero, 0
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addi x15, zero, 0
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addi x16, zero, 0
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addi x17, zero, 0
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addi x18, zero, 0
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addi x19, zero, 0
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addi x20, zero, 0
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addi x21, zero, 0
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addi x22, zero, 0
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addi x23, zero, 0
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addi x24, zero, 0
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addi x25, zero, 0
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addi x26, zero, 0
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addi x27, zero, 0
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addi x28, zero, 0
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addi x29, zero, 0
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addi x30, zero, 0
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addi x31, zero, 0
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/* set stack pointer */
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lui sp, %hi(4*1024*1024)
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addi sp, sp, %lo(4*1024*1024)
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/*
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lui sp, %hi(0x100000)
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addi sp, sp, %lo(0x100000)
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*/
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/* push zeros on the stack for argc and argv */
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/* (stack is aligned to 16 bytes in riscv calling convention) */
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addi sp,sp,-16
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sw zero,0(sp)
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sw zero,4(sp)
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sw zero,8(sp)
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sw zero,12(sp)
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/*
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// Load data section
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la a0, _data_lma
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la a1, _data
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la a2, _edata
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bgeu a1, a2, 2f
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1:
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lw t0, (a0)
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sw t0, (a1)
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addi a0, a0, 4
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addi a1, a1, 4
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bltu a1, a2, 1b
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2:
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// Clear bss section
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la a0, _bss_start
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la a1, _bss_end
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bgeu a0, a1, 2f
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1:
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sw zero, (a0)
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addi a0, a0, 4
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bltu a0, a1, 1b
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2:
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*/
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/* jump to libc init */
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/*j _ftext
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*/
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j _start
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