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-rw-r--r--kernel/arch/h8300/lib/muldi3.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/kernel/arch/h8300/lib/muldi3.c b/kernel/arch/h8300/lib/muldi3.c
new file mode 100644
index 000000000..790512243
--- /dev/null
+++ b/kernel/arch/h8300/lib/muldi3.c
@@ -0,0 +1,44 @@
+#include "libgcc.h"
+
+#define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
+#define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
+#define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
+
+#define umul_ppmm(w1, w0, u, v) \
+ do { \
+ UWtype __x0, __x1, __x2, __x3; \
+ UHWtype __ul, __vl, __uh, __vh; \
+ __ul = __ll_lowpart(u); \
+ __uh = __ll_highpart(u); \
+ __vl = __ll_lowpart(v); \
+ __vh = __ll_highpart(v); \
+ __x0 = (UWtype) __ul * __vl; \
+ __x1 = (UWtype) __ul * __vh; \
+ __x2 = (UWtype) __uh * __vl; \
+ __x3 = (UWtype) __uh * __vh; \
+ __x1 += __ll_highpart(__x0); \
+ __x1 += __x2; \
+ if (__x1 < __x2) \
+ __x3 += __ll_B; \
+ (w1) = __x3 + __ll_highpart(__x1); \
+ (w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0); \
+ } while (0)
+
+#define __umulsidi3(u, v) ( \
+ { \
+ DWunion __w; \
+ umul_ppmm(__w.s.high, __w.s.low, u, v); \
+ __w.ll; } \
+ )
+
+DWtype __muldi3(DWtype u, DWtype v)
+{
+ const DWunion uu = {.ll = u};
+ const DWunion vv = {.ll = v};
+ DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
+
+ w.s.high += ((UWtype) uu.s.low * (UWtype) vv.s.high
+ + (UWtype) uu.s.high * (UWtype) vv.s.low);
+
+ return w.ll;
+}