60 lines
1.2 KiB
ArmAsm
60 lines
1.2 KiB
ArmAsm
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.section .init
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.global _start
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.type _start,@function
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_start:
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// If we're on a multicore system, we need to wait for hart 0 to wake us up.
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#if TINYGO_CORES > 1
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csrr a0, mhartid
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// Hart 0 stack
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bnez a0, 1f
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la sp, _stack_top
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1:
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// Hart 1 stack
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li a1, 1
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bne a0, a1, 2f
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la sp, _stack1_top
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2:
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// Hart 2 stack
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#if TINYGO_CORES >= 3
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li a1, 2
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bne a0, a1, 3f
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la sp, _stack2_top
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#endif
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3:
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// Hart 3 stack
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#if TINYGO_CORES >= 4
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li a1, 3
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bne a0, a1, 4f
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la sp, _stack3_top
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#endif
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4:
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// done
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#if TINYGO_CORES > 4
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#error only up to 4 cores are supported at the moment!
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#endif
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#else
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// Load the stack pointer.
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la sp, _stack_top
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#endif
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// Load the globals pointer. The program will load pointers relative to this
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// register, so it must be set to the right value on startup.
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// See: https://gnu-mcu-eclipse.github.io/arch/riscv/programmer/#the-gp-global-pointer-register
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// Linker relaxations must be disabled to avoid the initialization beign
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// relaxed with an uninitialized global pointer: mv gp, gp
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.option push
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.option norelax
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la gp, __global_pointer$
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.option pop
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// Jump to runtime.main
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call main
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