Add __divmodti4 to match libgcc.

gcc has used this on x86-64 since at least version 7.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D80506

diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index 8dbe15364ab8ea92cc8a956466651afa5675a943..3c50df1797640ba3d2b8ba69c3ce76d64c7279d9 100644 (file)
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -71,6 +71,7 @@ set(GENERIC_SOURCES
   divdi3.c
   divmoddi4.c
   divmodsi4.c
+  divmodti4.c
   divsc3.c
   divsf3.c
   divsi3.c

diff --git a/compiler-rt/lib/builtins/README.txt b/compiler-rt/lib/builtins/README.txt
index f9e1bc805092e648e48270434825cc6be4f3f1ca..d66d725e7ab59a8c1fba93976301a5312bd02f39 100644 (file)
--- a/compiler-rt/lib/builtins/README.txt
+++ b/compiler-rt/lib/builtins/README.txt
@@ -87,6 +87,8 @@ du_int __udivmoddi4(du_int a, du_int b, du_int* rem);  // a / b, *rem = a % b  u
 tu_int __udivmodti4(tu_int a, tu_int b, tu_int* rem);  // a / b, *rem = a % b  unsigned
 su_int __udivmodsi4(su_int a, su_int b, su_int* rem);  // a / b, *rem = a % b  unsigned
 si_int __divmodsi4(si_int a, si_int b, si_int* rem);   // a / b, *rem = a % b  signed
+di_int __divmoddi4(di_int a, di_int b, di_int* rem);   // a / b, *rem = a % b  signed
+ti_int __divmodti4(ti_int a, ti_int b, ti_int* rem);   // a / b, *rem = a % b  signed
 
 
 

diff --git a/compiler-rt/lib/builtins/divmodti4.c b/compiler-rt/lib/builtins/divmodti4.c
new file mode 100644 (file)
index 0000000..b243ba4
--- /dev/null
+++ b/compiler-rt/lib/builtins/divmodti4.c
@@ -0,0 +1,32 @@
+//===-- divmodti4.c - Implement __divmodti4 -------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __divmodti4 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+#ifdef CRT_HAS_128BIT
+
+// Returns: a / b, *rem = a % b
+
+COMPILER_RT_ABI ti_int __divmodti4(ti_int a, ti_int b, ti_int *rem) {
+  const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1;
+  ti_int s_a = a >> bits_in_tword_m1;                   // s_a = a < 0 ? -1 : 0
+  ti_int s_b = b >> bits_in_tword_m1;                   // s_b = b < 0 ? -1 : 0
+  a = (a ^ s_a) - s_a;                                  // negate if s_a == -1
+  b = (b ^ s_b) - s_b;                                  // negate if s_b == -1
+  s_b ^= s_a;                                           // sign of quotient
+  tu_int r;
+  ti_int q = (__udivmodti4(a, b, &r) ^ s_b) - s_b;      // negate if s_b == -1
+  *rem = (r ^ s_a) - s_a;                               // negate if s_a == -1
+  return q;
+}
+
+#endif // CRT_HAS_128BIT

diff --git a/compiler-rt/test/builtins/Unit/divmodti4_test.c b/compiler-rt/test/builtins/Unit/divmodti4_test.c
new file mode 100644 (file)
index 0000000..a9f70dc
--- /dev/null
+++ b/compiler-rt/test/builtins/Unit/divmodti4_test.c
@@ -0,0 +1,91 @@
+// RUN: %clang_builtins %s %librt -o %t && %run %t
+// REQUIRES: librt_has_divmodti4
+// REQUIRES: int128
+//===-- divmodti4_test.c - Test __divmodti4 -------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file tests __divmodti4 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+#include <stdio.h>
+
+#ifdef CRT_HAS_128BIT
+
+// Effects: if rem != 0, *rem = a % b
+// Returns: a / b
+
+COMPILER_RT_ABI ti_int __divmodti4(ti_int a, ti_int b, ti_int* rem);
+
+int test__divmodti4(ti_int a, ti_int b, ti_int expected_q, ti_int expected_r) {
+    ti_int r;
+    ti_int q = __divmodti4(a, b, &r);
+    if (q != expected_q || r != expected_r)
+    {
+        utwords at;
+        at.all = a;
+        utwords bt;
+        bt.all = b;
+        utwords expected_qt;
+        expected_qt.all = expected_q;
+        utwords expected_rt;
+        expected_rt.all = expected_r;
+        utwords qt;
+        qt.all = q;
+        utwords rt;
+        rt.all = r;
+        printf("error in __divmodti4: 0x%.16llX%.16llX / 0x%.16llX%.16llX = "
+               "0x%.16llX%.16llX, R = 0x%.16llX%.16llX, expected 0x%.16llX%.16llX, "
+               "0x%.16llX%.16llX\n",
+               at.s.high, at.s.low, bt.s.high, bt.s.low, qt.s.high, qt.s.low,
+               rt.s.high, rt.s.low, expected_qt.s.high, expected_qt.s.low,
+               expected_rt.s.high, expected_rt.s.low);
+    }
+    return !(q == expected_q && r == expected_r);
+}
+
+char assumption_1[sizeof(ti_int) == 2*sizeof(di_int)] = {0};
+
+tu_int tests[][4] =
+{
+{ (ti_int) 0,                             (ti_int) 1, (ti_int) 0,                                                (ti_int) 0 },
+{ (ti_int) 0,                             (ti_int)-1, (ti_int) 0,                                                (ti_int) 0 },
+{ (ti_int) 2,                             (ti_int) 1, (ti_int) 2,                                                (ti_int) 0 },
+{ (ti_int) 2,                             (ti_int)-1, (ti_int)-2,                                                (ti_int) 0 },
+{ (ti_int)-2,                             (ti_int) 1, (ti_int)-2,                                                (ti_int) 0 },
+{ (ti_int)-2,                             (ti_int)-1, (ti_int) 2,                                                (ti_int) 0 },
+{ (ti_int) 5,                             (ti_int) 3, (ti_int) 1,                                                (ti_int) 2 },
+{ (ti_int) 5,                             (ti_int)-3, (ti_int)-1,                                                (ti_int) 2 },
+{ (ti_int)-5,                             (ti_int) 3, (ti_int)-1,                                                (ti_int)-2 },
+{ (ti_int)-5,                             (ti_int)-3, (ti_int) 1,                                                (ti_int)-2 },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int) 1, (ti_int)0x8000000000000000LL << 64 | 0,                    (ti_int)0x0LL },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int)-1, (ti_int)0x8000000000000000LL << 64 | 0,                    (ti_int)0x0LL },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int)-2, (ti_int)0x4000000000000000LL << 64 | 0,                    (ti_int)0x0LL },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int) 2, (ti_int)0xC000000000000000LL << 64 | 0,                    (ti_int)0x0LL },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int)-3, (ti_int)0x2AAAAAAAAAAAAAAALL << 64 | 0xAAAAAAAAAAAAAAAALL, (ti_int)-2 },
+{ (ti_int)0x8000000000000000LL << 64 | 0, (ti_int) 3, (ti_int)0xD555555555555555LL << 64 | 0x5555555555555556LL, (ti_int)-2 },
+};
+
+#endif
+
+int main()
+{
+#ifdef CRT_HAS_128BIT
+    const unsigned N = sizeof(tests) / sizeof(tests[0]);
+    unsigned i;
+    for (i = 0; i < N; ++i)
+        if (test__divmodti4(tests[i][0], tests[i][1], tests[i][2], tests[i][3]))
+            return 1;
+
+
+#else
+    printf("skipped\n");
+#endif
+    return 0;
+}