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# --------------------------------------------
# FUNCTION: parse_file
# PURPOSE : Parses the file into the array format.
# INPUTS : rdi = File descriptor
# OUTPUTS : rax = address of array
# rdx = length of array in 8 byte chunks
# CLOBBERS: none
# NOTES : Preserves all registers.
# --------------------------------------------
.section .text
.globl parse_file
.type parse_file, @function
parse_file:
# Save registers
push %rbx
push %rbp
push %r12
push %r13
push %r14
push %r15
movq %rdi, %r15 # Save file descriptor in r15
movq %r15, %rdi # Select file descriptor
call getFileSize # Get the file size
movq %rax, %r14 # Save file size in r14
movq %r14, %rdi # Select file size
call allocate # Allocate memory for file contents
movq %rax, %r13 # Save file buffer in r13
movq %r15, %rdi # Select the file discriptor
movq %r13, %rsi # Select the buffer to store input
movq %r14, %rdx # Size to read from file
movq $0, %rax # Select read syscall
syscall # Read from the file
movq %r13, %rdi # Select buffer for file contents
movq %r14, %rsi # Select file size
call getLineCount # Count lines
movq %rax, %r12 # Save line count in r12
movq %r12, %rdi # Select number of coordinates
call make_coordinate_buffer # Create buffer
movq %rax, %r13 # Override file buffer with coordinate buffer
movq %r13, %rdi # Select coordinate buffer
movq %r12, %rsi # Select number of coordinates
call build_pointer_buffer # Create final array of pointers
movq %rax, %rax # Return pointer to array
movq %r12, %rdx # Return Number of coordinates
# Restore registers
pop %r15
pop %r14
pop %r13
pop %r12
pop %rbp
pop %rbx
ret
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