[compiler-rt] 47481cb - [test] Deflake test/profile/ContinuousSyncMode/online-merging.c

[Vedant Kumar via llvm-commits]

Author: Vedant Kumar
Date: 2020-07-02T13:31:56-07:00
New Revision: 47481cbffbefb399e672cf056c15323917bf43bf

URL: https://github.com/llvm/llvm-project/commit/47481cbffbefb399e672cf056c15323917bf43bf
DIFF: https://github.com/llvm/llvm-project/commit/47481cbffbefb399e672cf056c15323917bf43bf.diff

LOG: [test] Deflake test/profile/ContinuousSyncMode/online-merging.c

This test spawns 32 child processes which race to update counters on
shared memory pages. On some Apple-internal machines, two processes race
to perform an update in approximately 0.5% of the test runs, leading to
dropped counter updates. Deflake the test by using atomic increments.

Tested with:

```
$ for I in $(seq 1 1000); do echo ":: Test run $I..."; ./bin/llvm-lit projects/compiler-rt/test/profile/Profile-x86_64h/ContinuousSyncMode/online-merging.c -av || break; done
```

rdar://64956774

Added: 
    

Modified: 
    compiler-rt/test/profile/ContinuousSyncMode/online-merging.c

Removed: 
    


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diff  --git a/compiler-rt/test/profile/ContinuousSyncMode/online-merging.c b/compiler-rt/test/profile/ContinuousSyncMode/online-merging.c
index a9f32b9c51e1..b3c33f339713 100644
--- a/compiler-rt/test/profile/ContinuousSyncMode/online-merging.c
+++ b/compiler-rt/test/profile/ContinuousSyncMode/online-merging.c
@@ -8,9 +8,9 @@
 // Create two DSOs and a driver program that uses them.
 // RUN: echo "void dso1(void) {}" > dso1.c
 // RUN: echo "void dso2(void) {}" > dso2.c
-// RUN: %clang_pgogen -dynamiclib -o %t.dir/dso1.dylib dso1.c
-// RUN: %clang_pgogen -dynamiclib -o %t.dir/dso2.dylib dso2.c
-// RUN: %clang_pgogen -o main.exe %s %t.dir/dso1.dylib %t.dir/dso2.dylib
+// RUN: %clang_pgogen -dynamiclib -o %t.dir/dso1.dylib dso1.c -mllvm -instrprof-atomic-counter-update-all=1
+// RUN: %clang_pgogen -dynamiclib -o %t.dir/dso2.dylib dso2.c -mllvm -instrprof-atomic-counter-update-all=1
+// RUN: %clang_pgogen -o main.exe %s %t.dir/dso1.dylib %t.dir/dso2.dylib -mllvm -instrprof-atomic-counter-update-all=1
 //
 // === Round 1 ===
 // Test merging+continuous mode without any file contention.