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Diffstat (limited to 'src/internal/i386/syscall.s')
-rw-r--r--src/internal/i386/syscall.s81
1 files changed, 12 insertions, 69 deletions
diff --git a/src/internal/i386/syscall.s b/src/internal/i386/syscall.s
index 0ebf2218..004ddfef 100644
--- a/src/internal/i386/syscall.s
+++ b/src/internal/i386/syscall.s
@@ -1,78 +1,21 @@
-.hidden __sysinfo
-
-# The calling convention for __vsyscall has the syscall number
-# and 5 args arriving as: eax, edx, ecx, edi, esi, 4(%esp).
-# This ensures that the inline asm in the C code never has to touch
-# ebx or ebp (which are unavailable in PIC and frame-pointer-using
-# code, respectively), and optimizes for size/simplicity in the caller.
-
-.global __vsyscall
-.hidden __vsyscall
-.type __vsyscall,@function
-__vsyscall:
- push %edi
- push %ebx
- mov %edx,%ebx
- mov %edi,%edx
- mov 12(%esp),%edi
- push %eax
- call 1f
-2: mov %ebx,%edx
- pop %ebx
- pop %ebx
- pop %edi
- ret
-
-1: mov (%esp),%eax
- add $[__sysinfo-2b],%eax
- mov (%eax),%eax
- test %eax,%eax
- jz 1f
- push %eax
- mov 8(%esp),%eax
- ret # tail call to kernel vsyscall entry
-1: mov 4(%esp),%eax
- int $128
- ret
-
-# The __vsyscall6 entry point is used only for 6-argument syscalls.
-# Instead of passing the 5th argument on the stack, a pointer to the
-# 5th and 6th arguments is passed. This is ugly, but there are no
-# register constraints the inline asm could use that would make it
-# possible to pass two arguments on the stack.
-
-.global __vsyscall6
-.hidden __vsyscall6
-.type __vsyscall6,@function
-__vsyscall6:
- push %ebp
- push %eax
- mov 12(%esp), %ebp
- mov (%ebp), %eax
- mov 4(%ebp), %ebp
- push %eax
- mov 4(%esp),%eax
- call __vsyscall
- pop %ebp
- pop %ebp
- pop %ebp
- ret
-
.global __syscall
.hidden __syscall
.type __syscall,@function
__syscall:
- lea 24(%esp),%eax
+ push %ebx
push %esi
push %edi
- push %eax
- mov 16(%esp),%eax
- mov 20(%esp),%edx
- mov 24(%esp),%ecx
- mov 28(%esp),%edi
- mov 32(%esp),%esi
- call __vsyscall6
- pop %edi
+ push %ebp
+ mov 20(%esp),%eax
+ mov 24(%esp),%ebx
+ mov 28(%esp),%ecx
+ mov 32(%esp),%edx
+ mov 36(%esp),%esi
+ mov 40(%esp),%edi
+ mov 44(%esp),%ebp
+ call *%gs:16
+ pop %ebp
pop %edi
pop %esi
+ pop %ebx
ret