Index: llvm/include/llvm/Support/Program.h
===================================================================
--- llvm/include/llvm/Support/Program.h
+++ llvm/include/llvm/Support/Program.h
@@ -205,22 +205,27 @@
   /// \li 0 if the child process has not changed state.
   /// \note Users of this function should always check the ReturnCode member of
   /// the \see ProcessInfo returned from this function.
-  ProcessInfo Wait(
-      const ProcessInfo &PI, ///< The child process that should be waited on.
-      std::optional<unsigned> SecondsToWait, ///< If std::nullopt, waits until
-      ///< child has terminated.
-      ///< If a value, this specifies the amount of time to wait for the child
-      ///< process to exit. If the time expires, the child is killed and this
-      ///< function returns. If zero, this function will perform a non-blocking
-      ///< wait on the child process.
-      std::string *ErrMsg = nullptr, ///< If non-zero, provides a pointer to a
-      ///< string instance in which error messages will be returned. If the
-      ///< string is non-empty upon return an error occurred while invoking the
-      ///< program.
-      std::optional<ProcessStatistics> *ProcStat =
-          nullptr ///< If non-zero, provides
-      /// a pointer to a structure in which process execution statistics will
-      /// be stored.
+  ProcessInfo
+  Wait(const ProcessInfo &PI, ///< The child process that should be waited on.
+       std::optional<unsigned> SecondsToWait, ///< If std::nullopt, waits until
+       ///< child has terminated.
+       ///< If a value, this specifies the amount of time to wait for the child
+       ///< process. If the time expires, and \p Polling is false, the child is
+       ///< killed and this < function returns. If the time expires and \p
+       ///< Polling is true, the child is resumed.
+       ///<
+       ///< If zero, this function will perform a non-blocking
+       ///< wait on the child process.
+       std::string *ErrMsg = nullptr, ///< If non-zero, provides a pointer to a
+       ///< string instance in which error messages will be returned. If the
+       ///< string is non-empty upon return an error occurred while invoking the
+       ///< program.
+       std::optional<ProcessStatistics> *ProcStat =
+           nullptr, ///< If non-zero, provides
+       /// a pointer to a structure in which process execution statistics will
+       /// be stored.
+
+       bool Polling = false ///< If true, do not kill the process on timeout.
   );
 
   /// Print a command argument, and optionally quote it.
Index: llvm/lib/Support/Unix/Program.inc
===================================================================
--- llvm/lib/Support/Unix/Program.inc
+++ llvm/lib/Support/Unix/Program.inc
@@ -385,7 +385,8 @@
 
 ProcessInfo llvm::sys::Wait(const ProcessInfo &PI, std::optional<unsigned> SecondsToWait,
                             std::string *ErrMsg,
-                            std::optional<ProcessStatistics> *ProcStat) {
+                            std::optional<ProcessStatistics> *ProcStat,
+                            bool Polling) {
   struct sigaction Act, Old;
   assert(PI.Pid && "invalid pid to wait on, process not started?");
 
@@ -403,7 +404,6 @@
     sigemptyset(&Act.sa_mask);
     sigaction(SIGALRM, &Act, &Old);
     // FIXME The alarm signal may be delivered to another thread.
-
     alarm(*SecondsToWait);
   } else {
     WaitPidOptions = WNOHANG;
@@ -426,6 +426,9 @@
       return WaitResult;
     } else {
       if (SecondsToWait && errno == EINTR) {
+        if (Polling)
+          return WaitResult;
+
         // Kill the child.
         kill(PI.Pid, SIGKILL);
 
Index: llvm/lib/Support/Windows/Program.inc
===================================================================
--- llvm/lib/Support/Windows/Program.inc
+++ llvm/lib/Support/Windows/Program.inc
@@ -409,7 +409,8 @@
 }
 
 ProcessInfo sys::Wait(const ProcessInfo &PI, std::optional<unsigned> SecondsToWait,
-                      std::string *ErrMsg, std::optional<ProcessStatistics> *ProcStat) {
+                      std::string *ErrMsg, std::optional<ProcessStatistics> *ProcStat,
+                      bool Polling) {
   assert(PI.Pid && "invalid pid to wait on, process not started?");
   assert((PI.Process && PI.Process != INVALID_HANDLE_VALUE) &&
          "invalid process handle to wait on, process not started?");
@@ -420,7 +421,7 @@
     ProcStat->reset();
   DWORD WaitStatus = WaitForSingleObject(PI.Process, milliSecondsToWait);
   if (WaitStatus == WAIT_TIMEOUT) {
-    if (*SecondsToWait > 0) {
+    if (!Polling && *SecondsToWait > 0) {
       if (!TerminateProcess(PI.Process, 1)) {
         if (ErrMsg)
           MakeErrMsg(ErrMsg, "Failed to terminate timed-out program");
Index: llvm/unittests/Support/ProgramTest.cpp
===================================================================
--- llvm/unittests/Support/ProgramTest.cpp
+++ llvm/unittests/Support/ProgramTest.cpp
@@ -284,6 +284,45 @@
   ASSERT_EQ(-2, RetCode);
 }
 
+TEST_F(ProgramEnvTest, TestExecuteNoWaitTimeoutPolling) {
+  using namespace llvm::sys;
+
+  if (getenv("LLVM_PROGRAM_TEST_TIMEOUT")) {
+    sleep_for(/*seconds*/ 5);
+    exit(0);
+  }
+
+  std::string Executable =
+      sys::fs::getMainExecutable(TestMainArgv0, &ProgramTestStringArg1);
+  StringRef argv[] = {
+      Executable,
+      "--gtest_filter=ProgramEnvTest.TestExecuteNoWaitTimeoutPolling"};
+
+  // Add LLVM_PROGRAM_TEST_TIMEOUT to the environment of the child.
+  addEnvVar("LLVM_PROGRAM_TEST_TIMEOUT=1");
+
+  std::string Error;
+  bool ExecutionFailed;
+  ProcessInfo PI0 = ExecuteNoWait(Executable, argv, getEnviron(),
+                                  /*Redirects=*/ {}, /*MemoryLimit=*/ 0, &Error,
+                                  &ExecutionFailed);
+  ASSERT_FALSE(ExecutionFailed) << Error;
+  ASSERT_NE(PI0.Pid, ProcessInfo::InvalidPid) << "Invalid process id";
+
+  // Check that we don't kill the process with a non-0 SecondsToWait if Polling.
+  unsigned LoopCount = 0;
+  ProcessInfo WaitResult;
+  do {
+    ++LoopCount;
+    WaitResult = llvm::sys::Wait(PI0, /*SecondsToWait=*/ 1, &Error,
+                                 /*ProcStats=*/ nullptr,
+                                 /*Polling=*/ true);
+    ASSERT_TRUE(Error.empty()) << Error;
+  } while (WaitResult.Pid != PI0.Pid);
+
+  ASSERT_GT(LoopCount, 1u) << "LoopCount should be >1";
+}
+
 TEST(ProgramTest, TestExecuteNegative) {
   std::string Executable = "i_dont_exist";
   StringRef argv[] = {Executable};