Initial import of compiler-rt.
 -

llvm-svn: 74292
diff --git a/compiler-rt/lib/udivmoddi4.c b/compiler-rt/lib/udivmoddi4.c
new file mode 100644
index 0000000..ad4d2aa
--- /dev/null
+++ b/compiler-rt/lib/udivmoddi4.c
@@ -0,0 +1,236 @@
+//===-- udivmoddi4.c - Implement __udivmoddi4 -----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __udivmoddi4 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+// Effects: if rem != 0, *rem = a % b
+// Returns: a / b
+
+// Translated from Figure 3-40 of The PowerPC Compiler Writer's Guide
+
+du_int
+__udivmoddi4(du_int a, du_int b, du_int* rem)
+{
+    const unsigned n_uword_bits = sizeof(su_int) * CHAR_BIT;
+    const unsigned n_udword_bits = sizeof(du_int) * CHAR_BIT;
+    udwords n;
+    n.all = a;
+    udwords d;
+    d.all = b;
+    udwords q;
+    udwords r;
+    unsigned sr;
+    // special cases, X is unknown, K != 0
+    if (n.high == 0)
+    {
+        if (d.high == 0)
+        {
+            // 0 X
+            // ---
+            // 0 X
+            if (rem)
+                *rem = n.low % d.low;
+            return n.low / d.low;
+        }
+        // 0 X
+        // ---
+        // K X
+        if (rem)
+            *rem = n.low;
+        return 0;
+    }
+    // n.high != 0
+    if (d.low == 0)
+    {
+        if (d.high == 0)
+        {
+            // K X
+            // ---
+            // 0 0
+            if (rem)
+                *rem = n.high % d.low;
+            return n.high / d.low;
+        }
+        // d.high != 0
+        if (n.low == 0)
+        {
+            // K 0
+            // ---
+            // K 0
+            if (rem)
+            {
+                r.high = n.high % d.high;
+                r.low = 0;
+                *rem = r.all;
+            }
+            return n.high / d.high;
+        }
+        // K K
+        // ---
+        // K 0
+        if ((d.high & (d.high - 1)) == 0)     // if d is a power of 2
+        {
+            if (rem)
+            {
+                r.low = n.low;
+                r.high = n.high & (d.high - 1);
+                *rem = r.all;
+            }
+            return n.high >> __builtin_ctz(d.high);
+        }
+        // K K
+        // ---
+        // K 0
+        sr = __builtin_clz(d.high) - __builtin_clz(n.high);
+        // 0 <= sr <= n_uword_bits - 2 or sr large
+        if (sr > n_uword_bits - 2)
+        {
+           if (rem)
+                *rem = n.all;
+            return 0;
+        }
+        ++sr;
+        // 1 <= sr <= n_uword_bits - 1
+        // q.all = n.all << (n_udword_bits - sr);
+        q.low = 0;
+        q.high = n.low << (n_uword_bits - sr);
+        // r.all = n.all >> sr;
+        r.high = n.high >> sr;
+        r.low = (n.high << (n_uword_bits - sr)) | (n.low >> sr);
+    }
+    else  // d.low != 0
+    {
+        if (d.high == 0)
+        {
+            // K X
+            // ---
+            // 0 K
+            if ((d.low & (d.low - 1)) == 0)     // if d is a power of 2
+            {
+                if (rem)
+                    *rem = n.low & (d.low - 1);
+                if (d.low == 1)
+                    return n.all;
+                unsigned sr = __builtin_ctz(d.low);
+                q.high = n.high >> sr;
+                q.low = (n.high << (n_uword_bits - sr)) | (n.low >> sr);
+                return q.all;
+            }
+            // K X
+            // ---
+            // 0 K
+            sr = 1 + n_uword_bits + __builtin_clz(d.low) - __builtin_clz(n.high);
+            // 2 <= sr <= n_udword_bits - 1
+            // q.all = n.all << (n_udword_bits - sr);
+            // r.all = n.all >> sr;
+            // if (sr == n_uword_bits)
+            // {
+            //     q.low = 0;
+            //     q.high = n.low;
+            //     r.high = 0;
+            //     r.low = n.high;
+            // }
+            // else if (sr < n_uword_bits)  // 2 <= sr <= n_uword_bits - 1
+            // {
+            //     q.low = 0;
+            //     q.high = n.low << (n_uword_bits - sr);
+            //     r.high = n.high >> sr;
+            //     r.low = (n.high << (n_uword_bits - sr)) | (n.low >> sr);
+            // }
+            // else              // n_uword_bits + 1 <= sr <= n_udword_bits - 1
+            // {
+            //     q.low = n.low << (n_udword_bits - sr);
+            //     q.high = (n.high << (n_udword_bits - sr)) |
+            //              (n.low >> (sr - n_uword_bits));
+            //     r.high = 0;
+            //     r.low = n.high >> (sr - n_uword_bits);
+            // }
+            q.low =  (n.low << (n_udword_bits - sr)) &
+                     ((si_int)(n_uword_bits - sr) >> (n_uword_bits-1));
+            q.high = ((n.low << ( n_uword_bits - sr))                       &
+                     ((si_int)(sr - n_uword_bits - 1) >> (n_uword_bits-1))) |
+                     (((n.high << (n_udword_bits - sr))                     |
+                     (n.low >> (sr - n_uword_bits)))                        &
+                     ((si_int)(n_uword_bits - sr) >> (n_uword_bits-1)));
+            r.high = (n.high >> sr) &
+                     ((si_int)(sr - n_uword_bits) >> (n_uword_bits-1));
+            r.low =  ((n.high >> (sr - n_uword_bits))                       &
+                     ((si_int)(n_uword_bits - sr - 1) >> (n_uword_bits-1))) |
+                     (((n.high << (n_uword_bits - sr))                      |
+                     (n.low >> sr))                                         &
+                     ((si_int)(sr - n_uword_bits) >> (n_uword_bits-1)));
+        }
+        else
+        {
+            // K X
+            // ---
+            // K K
+            sr = __builtin_clz(d.high) - __builtin_clz(n.high);
+            // 0 <= sr <= n_uword_bits - 1 or sr large
+            if (sr > n_uword_bits - 1)
+            {
+               if (rem)
+                    *rem = n.all;
+                return 0;
+            }
+            ++sr;
+            // 1 <= sr <= n_uword_bits
+            // q.all = n.all << (n_udword_bits - sr);
+            q.low = 0;
+            q.high = n.low << (n_uword_bits - sr);
+            // r.all = n.all >> sr;
+            // if (sr < n_uword_bits)
+            // {
+            //     r.high = n.high >> sr;
+            //     r.low = (n.high << (n_uword_bits - sr)) | (n.low >> sr);
+            // }
+            // else
+            // {
+            //     r.high = 0;
+            //     r.low = n.high;
+            // }
+            r.high = (n.high >> sr) &
+                     ((si_int)(sr - n_uword_bits) >> (n_uword_bits-1));
+            r.low = (n.high << (n_uword_bits - sr)) |
+                    ((n.low >> sr)                  &
+                    ((si_int)(sr - n_uword_bits) >> (n_uword_bits-1)));
+        }
+    }
+    // Not a special case
+    // q and r are initialized with:
+    // q.all = n.all << (n_udword_bits - sr);
+    // r.all = n.all >> sr;
+    // 1 <= sr <= n_udword_bits - 1
+    su_int carry = 0;
+    for (; sr > 0; --sr)
+    {
+        // r:q = ((r:q)  << 1) | carry
+        r.high = (r.high << 1) | (r.low  >> (n_uword_bits - 1));
+        r.low  = (r.low  << 1) | (q.high >> (n_uword_bits - 1));
+        q.high = (q.high << 1) | (q.low  >> (n_uword_bits - 1));
+        q.low  = (q.low  << 1) | carry;
+        // carry = 0;
+        // if (r.all >= d.all)
+        // {
+        //      r.all -= d.all;
+        //      carry = 1;
+        // }
+        const di_int s = (di_int)(d.all - r.all - 1) >> (n_udword_bits - 1);
+        carry = s & 1;
+        r.all -= d.all & s;
+    }
+    q.all = (q.all << 1) | carry;
+    if (rem)
+        *rem = r.all;
+    return q.all;
+}