[compiler-rt] c9af340 - Add __divmodti4 to match libgcc.
Craig Topper via llvm-commits
llvm-commits at lists.llvm.org
Wed Sep 16 21:56:46 PDT 2020
Author: Craig Topper
Date: 2020-09-16T21:56:01-07:00
New Revision: c9af34027bc9cb852a4e5e96154a7bd89531a6de
URL: https://github.com/llvm/llvm-project/commit/c9af34027bc9cb852a4e5e96154a7bd89531a6de
DIFF: https://github.com/llvm/llvm-project/commit/c9af34027bc9cb852a4e5e96154a7bd89531a6de.diff
LOG: 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
Added:
compiler-rt/lib/builtins/divmodti4.c
compiler-rt/test/builtins/Unit/divmodti4_test.c
Modified:
compiler-rt/lib/builtins/CMakeLists.txt
compiler-rt/lib/builtins/README.txt
Removed:
################################################################################
diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
index 8dbe15364ab8..3c50df179764 100644
--- 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 f9e1bc805092..d66d725e7ab5 100644
--- 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
index 000000000000..b243ba4ef853
--- /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
index 000000000000..a9f70dcf1c1e
--- /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;
+}
More information about the llvm-commits
mailing list