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-rw-r--r--usr/klibc/arch/i386/setjmp.S58
1 files changed, 58 insertions, 0 deletions
diff --git a/usr/klibc/arch/i386/setjmp.S b/usr/klibc/arch/i386/setjmp.S
new file mode 100644
index 0000000..b766792
--- /dev/null
+++ b/usr/klibc/arch/i386/setjmp.S
@@ -0,0 +1,58 @@
+#
+# arch/i386/setjmp.S
+#
+# setjmp/longjmp for the i386 architecture
+#
+
+#
+# The jmp_buf is assumed to contain the following, in order:
+# %ebx
+# %esp
+# %ebp
+# %esi
+# %edi
+# <return address>
+#
+
+ .text
+ .align 4
+ .globl setjmp
+ .type setjmp, @function
+setjmp:
+#ifdef _REGPARM
+ movl %eax,%edx
+#else
+ movl 4(%esp),%edx
+#endif
+ popl %ecx # Return address, and adjust the stack
+ xorl %eax,%eax # Return value
+ movl %ebx,(%edx)
+ movl %esp,4(%edx) # Post-return %esp!
+ pushl %ecx # Make the call/return stack happy
+ movl %ebp,8(%edx)
+ movl %esi,12(%edx)
+ movl %edi,16(%edx)
+ movl %ecx,20(%edx) # Return address
+ ret
+
+ .size setjmp,.-setjmp
+
+ .text
+ .align 4
+ .globl longjmp
+ .type longjmp, @function
+longjmp:
+#ifdef _REGPARM
+ xchgl %eax,%edx
+#else
+ movl 4(%esp),%edx # jmp_ptr address
+ movl 8(%esp),%eax # Return value
+#endif
+ movl (%edx),%ebx
+ movl 4(%edx),%esp
+ movl 8(%edx),%ebp
+ movl 12(%edx),%esi
+ movl 16(%edx),%edi
+ jmp *20(%edx)
+
+ .size longjmp,.-longjmp