38 lines
837 B
ArmAsm
38 lines
837 B
ArmAsm
# We will be using R0 request a number of bytes
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# The pointer to the block of that size is to be
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# passed back in R0, for simplicity sake
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# R15 will be used as the stack pointer
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:start
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LOADUI R15 @stack
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LOADUI R0 22 ; Allocate 22 bytes
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CALLI R15 @malloc
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LOADUI R0 42 ; Allocate 42 bytes
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CALLI R15 @malloc
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HALT
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;; Our simple malloc function
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:malloc
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;; Preserve registers
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PUSHR R1 R15
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;; Get current malloc pointer
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LOADR R1 @malloc_pointer
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;; Deal with special case
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CMPSKIPI.NE R1 0 ; If Zero set to our start of heap space
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LOADUI R1 0x600
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;; update malloc pointer
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SWAP R0 R1
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ADD R1 R0 R1
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STORER R1 @malloc_pointer
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;; Done
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;; Restore registers
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POPR R1 R15
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RET R15
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;; Our static value for malloc pointer
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:malloc_pointer
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NOP
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;; Start stack at end of instructions
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:stack
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