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+# Copyright 2022-2023 Gabriel Jensen.
+# This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
+# If a copy of the MPL was not distributed with this file, You can obtain one at <https://mozilla.org/MPL/2.0>.
+
+.globl zap_syscall
+
+zap_syscall:
+ # System calls on AMD64 use the following registers:
+ # rax : System call identifier
+ # rdi : First parameter
+ # rsi : Second parameter
+ # rdx : Third parameter
+ # r10 : Fourth parameter
+ # r8 : Fifth parameter
+ # r9 : Sixth parameter
+ # eax : Return value
+ # No registers to save.
+ movq %rdi,%rax # Move the first parameter (the identifier) to rax.
+ movq %rsi,%rdi # Move parameters into their designated registers.
+ movq %rdx,%rsi
+ movq %rcx,%rdx
+ movq %r8,%r10 # System calls use r10 instead of rcx.
+ movq %r9,%r8
+ movq 0x8(%rsp),%r9 # Extract the sixth argument from the stack.
+ syscall # Slime incident
+ # No need to move the return value.
+ ret