1 files changed, 30 insertions, 0 deletions
diff --git a/lib/builtins/i386/muldi3.S b/lib/builtins/i386/muldi3.S
new file mode 100644
index 000000000000..15b6b4998456
--- /dev/null
+++ b/lib/builtins/i386/muldi3.S
@@ -0,0 +1,30 @@
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+
+#include "../assembly.h"
+
+// di_int __muldi3(di_int a, di_int b);
+
+#ifdef __i386__
+
+.text
+.balign 4
+DEFINE_COMPILERRT_FUNCTION(__muldi3)
+	pushl	%ebx
+	movl  16(%esp),		%eax	// b.lo
+	movl  12(%esp),		%ecx	// a.hi
+	imull	%eax,		%ecx	// b.lo * a.hi
+	
+	movl   8(%esp),		%edx	// a.lo
+	movl  20(%esp),		%ebx	// b.hi
+	imull	%edx,		%ebx	// a.lo * b.hi
+	
+	mull	%edx				// EDX:EAX = a.lo * b.lo
+	addl	%ecx,		%ebx	// EBX = (a.lo*b.hi + a.hi*b.lo)
+	addl	%ebx,		%edx
+	
+	popl	%ebx
+	retl
+END_COMPILERRT_FUNCTION(__muldi3)
+
+#endif // __i386__