[clang] Add flag fallow-runtime-check-skip-hot-cutoff (#145999)

Co-authored-by: Kazu Hirata <kazu@google.com>

3 files changed, 27 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 97bc063..1c92ea4 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -805,17 +805,21 @@ static void addSanitizers(const Triple &TargetTriple,
   // SanitizeSkipHotCutoffs: doubles with range [0, 1]
   // Opts.cutoffs: unsigned ints with range [0, 1000000]
   auto ScaledCutoffs = CodeGenOpts.SanitizeSkipHotCutoffs.getAllScaled(1000000);
-
+  uint64_t AllowRuntimeCheckSkipHotCutoff =
+      CodeGenOpts.AllowRuntimeCheckSkipHotCutoff.value_or(0.0) * 1000000;
   // TODO: remove IsRequested()
-  if (LowerAllowCheckPass::IsRequested() || ScaledCutoffs.has_value()) {
+  if (LowerAllowCheckPass::IsRequested() || ScaledCutoffs.has_value() ||
+      CodeGenOpts.AllowRuntimeCheckSkipHotCutoff.has_value()) {
     // We want to call it after inline, which is about OptimizerEarlyEPCallback.
     PB.registerOptimizerEarlyEPCallback(
-        [ScaledCutoffs](ModulePassManager &MPM, OptimizationLevel Level,
-                        ThinOrFullLTOPhase Phase) {
+        [ScaledCutoffs, AllowRuntimeCheckSkipHotCutoff](
+            ModulePassManager &MPM, OptimizationLevel Level,
+            ThinOrFullLTOPhase Phase) {
           LowerAllowCheckPass::Options Opts;
           // TODO: after removing IsRequested(), make this unconditional
           if (ScaledCutoffs.has_value())
             Opts.cutoffs = ScaledCutoffs.value();
+          Opts.runtime_check = AllowRuntimeCheckSkipHotCutoff;
           MPM.addPass(
               createModuleToFunctionPassAdaptor(LowerAllowCheckPass(Opts)));
         });
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 8a18865..ceb592d 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -6028,7 +6028,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // -fasynchronous-unwind-tables and -fnon-call-exceptions interact in more
   // complicated ways.
   auto SanitizeArgs = TC.getSanitizerArgs(Args);
-
+  Args.AddLastArg(CmdArgs,
+                  options::OPT_fallow_runtime_check_skip_hot_cutoff_EQ);
   bool IsAsyncUnwindTablesDefault =
       TC.getDefaultUnwindTableLevel(Args) == ToolChain::UnwindTableLevel::Asynchronous;
   bool IsSyncUnwindTablesDefault =
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 9e269ab..f366e90 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1820,6 +1820,11 @@ void CompilerInvocationBase::GenerateCodeGenArgs(const CodeGenOptions &Opts,
   for (std::string Sanitizer : Values)
     GenerateArg(Consumer, OPT_fsanitize_skip_hot_cutoff_EQ, Sanitizer);
 
+  if (Opts.AllowRuntimeCheckSkipHotCutoff) {
+    GenerateArg(Consumer, OPT_fallow_runtime_check_skip_hot_cutoff_EQ,
+                std::to_string(*Opts.AllowRuntimeCheckSkipHotCutoff));
+  }
+
   for (StringRef Sanitizer :
        serializeSanitizerKinds(Opts.SanitizeAnnotateDebugInfo))
     GenerateArg(Consumer, OPT_fsanitize_annotate_debug_info_EQ, Sanitizer);
@@ -2322,6 +2327,18 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
       Args.getAllArgValues(OPT_fsanitize_annotate_debug_info_EQ), Diags,
       Opts.SanitizeAnnotateDebugInfo);
 
+  if (StringRef V =
+          Args.getLastArgValue(OPT_fallow_runtime_check_skip_hot_cutoff_EQ);
+      !V.empty()) {
+    double A;
+    if (V.getAsDouble(A) || A < 0.0 || A > 1.0) {
+      Diags.Report(diag::err_drv_invalid_value)
+          << "-fallow-runtime-check-skip-hot-cutoff=" << V;
+    } else {
+      Opts.AllowRuntimeCheckSkipHotCutoff = A;
+    }
+  }
+
   Opts.EmitVersionIdentMetadata = Args.hasFlag(OPT_Qy, OPT_Qn, true);
 
   if (!LangOpts->CUDAIsDevice)