x86 libc: fix the wrong return value of syscall
According to Intel ABI spec, there is no need to save %eax, %ecx, %edx
on the stack. Worse, popping %eax will wipe out the return value.
Change-Id: Ida536c3b98174b8deef88f8f3b9352eaaeb7c0c0
diff --git a/libc/arch-x86/bionic/syscall.S b/libc/arch-x86/bionic/syscall.S
index 71abe6b..3cca85c 100644
--- a/libc/arch-x86/bionic/syscall.S
+++ b/libc/arch-x86/bionic/syscall.S
@@ -20,18 +20,15 @@
.align 4
syscall:
- push %eax
push %ebx
- push %ecx
- push %edx
push %esi
push %edi
- mov 28(%esp),%eax
- mov 32(%esp),%ebx
- mov 36(%esp),%ecx
- mov 40(%esp),%edx
- mov 44(%esp),%esi
- mov 48(%esp),%edi
+ mov 16(%esp),%eax
+ mov 20(%esp),%ebx
+ mov 24(%esp),%ecx
+ mov 28(%esp),%edx
+ mov 32(%esp),%esi
+ mov 36(%esp),%edi
int $0x80
@@ -45,8 +42,5 @@
1:
pop %edi
pop %esi
- pop %edx
- pop %ecx
pop %ebx
- pop %eax
ret