Rev 2479 | Show entire file | Ignore whitespace | Details | Blame | Last modification | View Log | RSS feed
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| 26 | # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
26 | # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | # |
27 | # |
| 28 | 28 | ||
| 29 | .text |
29 | .text |
| 30 | 30 | ||
| 31 | .globl __syscall |
31 | .global __syscall |
| 32 | - | ||
| 33 | 32 | ||
| - | 33 | ## Make a system call. |
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| - | 34 | # |
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| - | 35 | # @param rdi First argument. |
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| - | 36 | # @param rsi Second argument. |
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| - | 37 | # @param rdx Third argument. |
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| - | 38 | # @param rcx Fourth argument. |
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| - | 39 | # @param r8 Fifth argument. |
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| - | 40 | # @param r9 Sixth argument. |
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| - | 41 | # @param 8(%rsp) Syscall number. |
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| - | 42 | # |
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| - | 43 | # @return The return value will be stored in RAX. |
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| - | 44 | # |
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| 34 | __syscall: |
45 | __syscall: |
| - | 46 | # |
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| 35 | # rcx gets rewritten on syscall |
47 | # Move the syscall number into RAX. |
| - | 48 | movslq 8(%rsp), %rax |
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| - | 49 | ||
| - | 50 | # |
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| - | 51 | # Save RCX, the 4th argument, aside because RCX gets rewritten by the |
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| - | 52 | # SYSCALL instruction. |
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| - | 53 | # |
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| 36 | movq %rcx, %r9 |
54 | movq %rcx, %r10 |
| 37 | syscall |
55 | syscall |
| 38 | ret |
56 | ret |
| 39 | 57 | ||
| 40 | .end __syscall |
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