[llvm] c1d935e - [InstrProf] Fix BalancedPartitioning when threads are disabled

[Ellis Hoag via llvm-commits]

Author: Ellis Hoag
Date: 2023-06-07T12:04:35-07:00
New Revision: c1d935ece34679679bf0f5f52eb20cf3683949ae

URL: https://github.com/llvm/llvm-project/commit/c1d935ece34679679bf0f5f52eb20cf3683949ae
DIFF: https://github.com/llvm/llvm-project/commit/c1d935ece34679679bf0f5f52eb20cf3683949ae.diff

LOG: [InstrProf] Fix BalancedPartitioning when threads are disabled

In https://reviews.llvm.org/D147812 we introduced the class
`BalancedPartitioning` which includes some threading code. The tests in
that diff run forever when built with `-DLLVM_ENABLE_THREADS=OFF` so
some bots were broken.

These tests were skipped in
https://reviews.llvm.org/rGa4845eaf2e9aa18dd900d7cbeff4e5ff52e4b50e
because of this.

This diff disables the threading code if `LLVM_ENABLE_THREADS` is
disabled so we can re-enable the tests.

Reviewed By: luporl

Differential Revision: https://reviews.llvm.org/D152390

Added: 
    

Modified: 
    llvm/lib/Support/BalancedPartitioning.cpp
    llvm/test/tools/llvm-profdata/show-order.proftext
    llvm/unittests/Support/BalancedPartitioningTest.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Support/BalancedPartitioning.cpp b/llvm/lib/Support/BalancedPartitioning.cpp
index 324feeade089f..e45852ee8db8f 100644
--- a/llvm/lib/Support/BalancedPartitioning.cpp
+++ b/llvm/lib/Support/BalancedPartitioning.cpp
@@ -27,6 +27,7 @@ void BPFunctionNode::dump(raw_ostream &OS) const {
 
 template <typename Func>
 void BalancedPartitioning::BPThreadPool::async(Func &&F) {
+#if LLVM_ENABLE_THREADS
   // This new thread could spawn more threads, so mark it as active
   ++NumActiveThreads;
   TheThreadPool.async([=]() {
@@ -44,9 +45,13 @@ void BalancedPartitioning::BPThreadPool::async(Func &&F) {
       cv.notify_one();
     }
   });
+#else
+  llvm_unreachable("threads are disabled");
+#endif
 }
 
 void BalancedPartitioning::BPThreadPool::wait() {
+#if LLVM_ENABLE_THREADS
   // TODO: We could remove the mutex and condition variable and use
   // std::atomic::wait() instead, but that isn't available until C++20
   {
@@ -56,6 +61,9 @@ void BalancedPartitioning::BPThreadPool::wait() {
   }
   // Now we can call ThreadPool::wait() since all tasks have been submitted
   TheThreadPool.wait();
+#else
+  llvm_unreachable("threads are disabled");
+#endif
 }
 
 BalancedPartitioning::BalancedPartitioning(
@@ -73,8 +81,10 @@ void BalancedPartitioning::run(std::vector<BPFunctionNode> &Nodes) const {
           "Partitioning %d nodes using depth %d and %d iterations per split\n",
           Nodes.size(), Config.SplitDepth, Config.IterationsPerSplit));
   std::optional<BPThreadPool> TP;
+#if LLVM_ENABLE_THREADS
   if (Config.TaskSplitDepth > 1)
     TP.emplace();
+#endif
 
   // Record the input order
   for (unsigned I = 0; I < Nodes.size(); I++)

diff  --git a/llvm/test/tools/llvm-profdata/show-order.proftext b/llvm/test/tools/llvm-profdata/show-order.proftext
index 1b80677d5d063..8ef26847ad77e 100644
--- a/llvm/test/tools/llvm-profdata/show-order.proftext
+++ b/llvm/test/tools/llvm-profdata/show-order.proftext
@@ -1,6 +1,4 @@
 # RUN: llvm-profdata order %s | FileCheck %s
-# PR63168: Balanced Partitioning tests currently hang on ARM.
-# UNSUPPORTED: target=arm{{.*}}
 
 # CHECK: a
 # CHECK: b

diff  --git a/llvm/unittests/Support/BalancedPartitioningTest.cpp b/llvm/unittests/Support/BalancedPartitioningTest.cpp
index 05f7411b43277..ebe518a8e89ca 100644
--- a/llvm/unittests/Support/BalancedPartitioningTest.cpp
+++ b/llvm/unittests/Support/BalancedPartitioningTest.cpp
@@ -17,13 +17,6 @@ using testing::Not;
 using testing::UnorderedElementsAre;
 using testing::UnorderedElementsAreArray;
 
-// PR63168: Balanced Partitioning tests currently hang on ARM.
-#if defined(__arm__)
-#define SKIP_UNSUPPORTED_PLATFORM GTEST_SKIP()
-#else
-#define SKIP_UNSUPPORTED_PLATFORM do { } while(0)
-#endif
-
 namespace llvm {
 
 void PrintTo(const BPFunctionNode &Node, std::ostream *OS) {
@@ -47,7 +40,6 @@ class BalancedPartitioningTest : public ::testing::Test {
 };
 
 TEST_F(BalancedPartitioningTest, Basic) {
-  SKIP_UNSUPPORTED_PLATFORM;
   std::vector<BPFunctionNode> Nodes = {
       BPFunctionNode(0, {1, 2}), BPFunctionNode(2, {3, 4}),
       BPFunctionNode(1, {1, 2}), BPFunctionNode(3, {3, 4}),
@@ -67,7 +59,6 @@ TEST_F(BalancedPartitioningTest, Basic) {
 }
 
 TEST_F(BalancedPartitioningTest, Large) {
-  SKIP_UNSUPPORTED_PLATFORM;
   const int ProblemSize = 1000;
   std::vector<BPFunctionNode::UtilityNodeT> AllUNs;
   for (int i = 0; i < ProblemSize; i++)
@@ -94,7 +85,6 @@ TEST_F(BalancedPartitioningTest, Large) {
 }
 
 TEST_F(BalancedPartitioningTest, MoveGain) {
-  SKIP_UNSUPPORTED_PLATFORM;
   BalancedPartitioning::SignaturesT Signatures = {
       {10, 10, 10.f, 0.f, true}, // 0
       {10, 10, 0.f, 10.f, true}, // 1