1 files changed, 29 insertions, 0 deletions
diff --git a/win32/lib/chkstk.S b/win32/lib/chkstk.S
new file mode 100644
index 0000000..8e16d74
--- /dev/null
+++ b/win32/lib/chkstk.S
@@ -0,0 +1,29 @@
+// =================================================
+// chkstk.s
+
+.text
+.globl __chkstk
+
+__chkstk:
+	xchg    (%esp), %ebp   // store ebp, get ret.addr
+	push    %ebp           // push ret.addr
+	lea     4(%esp), %ebp  // setup frame ptr
+	push    %ecx           // save ecx
+	mov     %ebp, %ecx
+P0:
+	sub     $4096,%ecx
+	test    %eax,(%ecx)
+	sub     $4096,%eax
+	cmp     $4096,%eax
+	jge     P0
+
+	sub     %eax,%ecx
+	mov     %esp,%eax
+	test    %eax,(%ecx)
+	mov     %ecx,%esp
+
+	mov     (%eax),%ecx     // restore ecx
+	mov     4(%eax),%eax
+	push    %eax
+	ret
+