[Remarks] Make sure -fdiagnostics-hotness-threshold implies -fdiagnostics-show-hotness

[serge-sans-paille]

Summary

When asking for -fdiagnostics-hotness-threshold, we currently require
-fdiagnostics-show-hotness otherwise we silently display nothing.

I don't see a scenario where that makes sense, so have one option impy
the other.

[thegameg]

Makes sense, thanks.

clang/test/Frontend/remarks-hotness.cpp

 // Without hotness threshold, print both hot and cold remarks.
 // RUN: %clang_cc1 -triple x86_64-linux %s -emit-llvm-only -O3 \
 // RUN:     -fprofile-sample-use=%S/Inputs/remarks-hotness.prof \
 // RUN:     -Rpass=inline -Rpass-analysis=inline -Rpass-missed=inline \
 // RUN:     -fdiagnostics-show-hotness 2>&1 \
 // RUN:     | FileCheck -check-prefix=REMARKS %s
 
 // With auto hotness threshold, only print hot remarks.
 // RUN: %clang_cc1 -triple x86_64-linux %s -emit-llvm-only -O3 \
 // RUN:     -fprofile-sample-use=%S/Inputs/remarks-hotness.prof \
 // RUN:     -Rpass=inline -Rpass-analysis=inline -Rpass-missed=inline \
 // RUN:     -fdiagnostics-show-hotness \
 // RUN:     -fdiagnostics-hotness-threshold=auto 2>&1 \
 // RUN:     | FileCheck -check-prefix=HOT_CALL %s
 
+// Make sure -fdiagnostics-hotness-threshold implies -fdiagnostics-show-hotness
+// RUN: %clang_cc1 -triple x86_64-linux %s -emit-llvm-only -O3 \
+// RUN:     -fprofile-sample-use=%S/Inputs/remarks-hotness.prof \
+// RUN:     -Rpass=inline -Rpass-analysis=inline -Rpass-missed=inline \
+// RUN:     -fdiagnostics-hotness-threshold=auto 2>&1 \
+// RUN:     | FileCheck -check-prefix=HOT_CALL %s
+
 int callee1() {
   return 1;
 }
 
 __attribute__((noinline)) int callee2() {
   return 2;
 }
 

llvm/lib/IR/LLVMRemarkStreamer.cpp

 char LLVMRemarkSetupFileError::ID = 0;
 char LLVMRemarkSetupPatternError::ID = 0;
 char LLVMRemarkSetupFormatError::ID = 0;
 
 Expected<std::unique_ptr<ToolOutputFile>> llvm::setupLLVMOptimizationRemarks(
     LLVMContext &Context, StringRef RemarksFilename, StringRef RemarksPasses,
     StringRef RemarksFormat, bool RemarksWithHotness,
     std::optional<uint64_t> RemarksHotnessThreshold) {
-  if (RemarksWithHotness)
+  if (RemarksWithHotness || RemarksHotnessThreshold.value_or(1))
       Context.setDiagnosticsHotnessRequested(true);
 
   Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
 
   if (RemarksFilename.empty())
     return nullptr;
 
   Expected<remarks::Format> Format = remarks::parseFormat(RemarksFormat);
   if (Error E = Format.takeError())
Expected<std::unique_ptr<ToolOutputFile>> llvm::setupLLVMOptimizationRemarks(
 
   return std::move(RemarksFile);
 }
 
 Error llvm::setupLLVMOptimizationRemarks(
     LLVMContext &Context, raw_ostream &OS, StringRef RemarksPasses,
     StringRef RemarksFormat, bool RemarksWithHotness,
     std::optional<uint64_t> RemarksHotnessThreshold) {
-  if (RemarksWithHotness)
+  if (RemarksWithHotness || RemarksHotnessThreshold.value_or(1))
     Context.setDiagnosticsHotnessRequested(true);
 
   Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
 
   Expected<remarks::Format> Format = remarks::parseFormat(RemarksFormat);
   if (Error E = Format.takeError())
     return make_error<LLVMRemarkSetupFormatError>(std::move(E));