[clang] [CodeGen][OpenMP] Set the default schedule for loops to static,1 if TSan is enabled (PR #68891)
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git-clang-format --diff 30240e428f0ec7d4a6d1b84f9f807ce12b46cfd1 8b25e95008c4d794c4423d026c39382a0c7cfbf8 -- openmp/tools/archer/tests/races/DRB006-indirectaccess2-orig-yes.c clang/lib/CodeGen/CGOpenMPRuntime.cpp
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View the diff from clang-format here.
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diff --git a/openmp/tools/archer/tests/races/DRB006-indirectaccess2-orig-yes.c b/openmp/tools/archer/tests/races/DRB006-indirectaccess2-orig-yes.c
index c9d1bf0ae..bfa451484 100644
--- a/openmp/tools/archer/tests/races/DRB006-indirectaccess2-orig-yes.c
+++ b/openmp/tools/archer/tests/races/DRB006-indirectaccess2-orig-yes.c
@@ -57,19 +57,21 @@ THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
Two pointers have a distance of 12 (p1 - p2 = 12).
-They are used as base addresses for indirect array accesses using an index set (another array).
+They are used as base addresses for indirect array accesses using an index set
+(another array).
The index set has two indices with a distance of 12 :
indexSet[5]- indexSet[0] = 533 - 521 = 12
-So there is loop carried dependence (e.g. between loops with index values of 0 and 5).
+So there is loop carried dependence (e.g. between loops with index values of 0
+and 5).
We use the default loop scheduling (static even) in OpenMP.
It is possible that two dependent iterations will be scheduled
within a same chunk to a same thread. So there is no runtime data races.
When N is 180, two iterations with N=0 and N= 5 have loop carried dependencies.
-For static even scheduling, we must have at least 36 threads (180/36=5 iterations)
-so iteration 0 and 5 will be scheduled to two different threads.
+For static even scheduling, we must have at least 36 threads (180/36=5
+iterations) so iteration 0 and 5 will be scheduled to two different threads.
Data race pair: xa1[idx]@128:5:W vs. xa2[idx]@129:5:W
*/
@@ -78,74 +80,63 @@ Data race pair: xa1[idx]@128:5:W vs. xa2[idx]@129:5:W
// REQUIRES: tsan
#include <omp.h>
#include <stdio.h>
-#include <unistd.h>
#include <stdlib.h>
+#include <unistd.h>
#define NUM_THREADS 2
#define N 180
-int indexSet[N] = {
-521, 523, 525, 527, 529, 533, // 521+12=533
-547, 549, 551, 553, 555, 557,
-573, 575, 577, 579, 581, 583,
-599, 601, 603, 605, 607, 609,
-625, 627, 629, 631, 633, 635,
-
-651, 653, 655, 657, 659, 661,
-859, 861, 863, 865, 867, 869,
-885, 887, 889, 891, 893, 895,
-911, 913, 915, 917, 919, 921,
-937, 939, 941, 943, 945, 947,
-
-963, 965, 967, 969, 971, 973,
-989, 991, 993, 995, 997, 999,
-1197, 1199, 1201, 1203, 1205, 1207,
-1223, 1225, 1227, 1229, 1231, 1233,
-1249, 1251, 1253, 1255, 1257, 1259,
-
-1275, 1277, 1279, 1281, 1283, 1285,
-1301, 1303, 1305, 1307, 1309, 1311,
-1327, 1329, 1331, 1333, 1335, 1337,
-1535, 1537, 1539, 1541, 1543, 1545,
-1561, 1563, 1565, 1567, 1569, 1571,
-
-1587, 1589, 1591, 1593, 1595, 1597,
-1613, 1615, 1617, 1619, 1621, 1623,
-1639, 1641, 1643, 1645, 1647, 1649,
-1665, 1667, 1669, 1671, 1673, 1675,
-1873, 1875, 1877, 1879, 1881, 1883,
-
-1899, 1901, 1903, 1905, 1907, 1909,
-1925, 1927, 1929, 1931, 1933, 1935,
-1951, 1953, 1955, 1957, 1959, 1961,
-1977, 1979, 1981, 1983, 1985, 1987,
-2003, 2005, 2007, 2009, 2011, 2013};
-
-int main (int argc, char* argv[])
-{
- double * base = (double*) malloc(sizeof(double)* (2013+12+1));
+int indexSet[N] = {521, 523, 525, 527, 529, 533, // 521+12=533
+ 547, 549, 551, 553, 555, 557, 573, 575, 577, 579,
+ 581, 583, 599, 601, 603, 605, 607, 609, 625, 627,
+ 629, 631, 633, 635,
+
+ 651, 653, 655, 657, 659, 661, 859, 861, 863, 865,
+ 867, 869, 885, 887, 889, 891, 893, 895, 911, 913,
+ 915, 917, 919, 921, 937, 939, 941, 943, 945, 947,
+
+ 963, 965, 967, 969, 971, 973, 989, 991, 993, 995,
+ 997, 999, 1197, 1199, 1201, 1203, 1205, 1207, 1223, 1225,
+ 1227, 1229, 1231, 1233, 1249, 1251, 1253, 1255, 1257, 1259,
+
+ 1275, 1277, 1279, 1281, 1283, 1285, 1301, 1303, 1305, 1307,
+ 1309, 1311, 1327, 1329, 1331, 1333, 1335, 1337, 1535, 1537,
+ 1539, 1541, 1543, 1545, 1561, 1563, 1565, 1567, 1569, 1571,
+
+ 1587, 1589, 1591, 1593, 1595, 1597, 1613, 1615, 1617, 1619,
+ 1621, 1623, 1639, 1641, 1643, 1645, 1647, 1649, 1665, 1667,
+ 1669, 1671, 1673, 1675, 1873, 1875, 1877, 1879, 1881, 1883,
+
+ 1899, 1901, 1903, 1905, 1907, 1909, 1925, 1927, 1929, 1931,
+ 1933, 1935, 1951, 1953, 1955, 1957, 1959, 1961, 1977, 1979,
+ 1981, 1983, 1985, 1987, 2003, 2005, 2007, 2009, 2011, 2013};
+
+int main(int argc, char *argv[]) {
+ double *base = (double *)malloc(sizeof(double) * (2013 + 12 + 1));
if (base == 0) {
- printf ("Error in malloc(). Aborting ...\n");
- return 1;
+ printf("Error in malloc(). Aborting ...\n");
+ return 1;
}
- double * xa1 = base;
- double * xa2 = xa1 + 12;
+ double *xa1 = base;
+ double *xa2 = xa1 + 12;
int i;
// initialize segments touched by indexSet
- for (i =521; i<= 2025; ++i) {
- base[i]=0.5*i;
+ for (i = 521; i <= 2025; ++i) {
+ base[i] = 0.5 * i;
}
-#pragma omp parallel for num_threads(NUM_THREADS) //schedule(static, 1) // default static even scheduling may not trigger data race!
- for (i =0; i< N; ++i) {
+#pragma omp parallel for num_threads( \
+ NUM_THREADS) // schedule(static, 1) // default static even scheduling
+ // may not trigger data race!
+ for (i = 0; i < N; ++i) {
int idx = indexSet[i];
- xa1[idx]+= 1.0;
- xa2[idx]+= 3.0;
+ xa1[idx] += 1.0;
+ xa2[idx] += 3.0;
}
printf("x1[999]=%f xa2[1285]=%f\n", xa1[999], xa2[1285]);
- free (base);
+ free(base);
fprintf(stderr, "DONE\n");
return 0;
}
@@ -157,5 +148,3 @@ int main (int argc, char* argv[])
// CHECK-NEXT: #0 {{.*}}DRB006-indirectaccess2-orig-yes.c:145
// CHECK: DONE
// CHECK: ThreadSanitizer: reported {{[0-9]+}} warnings
-
-
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</details>
https://github.com/llvm/llvm-project/pull/68891
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