[clang][llvm][NFC] Change misexpect's tolerance option to be 32-bit

In D131869 we noticed that we jump through some hoops because we parse the
tolerance option used in MisExpect.cpp into a 64-bit integer. This is
unnecessary, since the value can only be in the range [0, 100).

This patch changes the underlying type to be 32-bit from where it is
parsed in Clang through to it's use in LLVM.

Reviewed By: jloser

Differential Revision: https://reviews.llvm.org/D131935

clang/include/clang/Basic/CodeGenOptions.h

@@ -424,7 +424,7 @@ public:
 
   /// The maximum percentage profiling weights can deviate from the expected
   /// values in order to be included in misexpect diagnostics.
-  Optional<uint64_t> DiagnosticsMisExpectTolerance = 0;
+  Optional<uint32_t> DiagnosticsMisExpectTolerance = 0;
 
 public:
   // Define accessors/mutators for code generation options of enumeration type.

clang/lib/Frontend/CompilerInvocation.cpp

@@ -113,8 +113,8 @@ using namespace llvm::opt;
 
 // Parse misexpect tolerance argument value.
 // Valid option values are integers in the range [0, 100)
-inline Expected<Optional<uint64_t>> parseToleranceOption(StringRef Arg) {
-  int64_t Val;
+inline Expected<Optional<uint32_t>> parseToleranceOption(StringRef Arg) {
+  uint32_t Val;
   if (Arg.getAsInteger(10, Val))
     return llvm::createStringError(llvm::inconvertibleErrorCode(),
                                    "Not an integer: %s", Arg.data());

llvm/include/llvm/IR/LLVMContext.h

@@ -204,8 +204,8 @@ public:
 
   bool getMisExpectWarningRequested() const;
   void setMisExpectWarningRequested(bool Requested);
-  void setDiagnosticsMisExpectTolerance(Optional<uint64_t> Tolerance);
-  uint64_t getDiagnosticsMisExpectTolerance() const;
+  void setDiagnosticsMisExpectTolerance(Optional<uint32_t> Tolerance);
+  uint32_t getDiagnosticsMisExpectTolerance() const;
 
   /// Return the minimum hotness value a diagnostic would need in order
   /// to be included in optimization diagnostics.

llvm/lib/IR/LLVMContext.cpp

@@ -148,10 +148,10 @@ uint64_t LLVMContext::getDiagnosticsHotnessThreshold() const {
   return pImpl->DiagnosticsHotnessThreshold.value_or(UINT64_MAX);
 }
 void LLVMContext::setDiagnosticsMisExpectTolerance(
-    Optional<uint64_t> Tolerance) {
+    Optional<uint32_t> Tolerance) {
   pImpl->DiagnosticsMisExpectTolerance = Tolerance;
 }
-uint64_t LLVMContext::getDiagnosticsMisExpectTolerance() const {
+uint32_t LLVMContext::getDiagnosticsMisExpectTolerance() const {
   return pImpl->DiagnosticsMisExpectTolerance.value_or(0);
 }
 

llvm/lib/IR/LLVMContextImpl.h

@@ -1387,8 +1387,8 @@ public:
   Optional<uint64_t> DiagnosticsHotnessThreshold = 0;
 
   /// The percentage of difference between profiling branch weights and
-  // llvm.expect branch weights to tolerate when emiting MisExpect diagnostics
-  Optional<uint64_t> DiagnosticsMisExpectTolerance = 0;
+  /// llvm.expect branch weights to tolerate when emiting MisExpect diagnostics
+  Optional<uint32_t> DiagnosticsMisExpectTolerance = 0;
   bool MisExpectWarningRequested = false;
 
   /// The specialized remark streamer used by LLVM's OptimizationRemarkEmitter.

llvm/lib/Transforms/Utils/MisExpect.cpp

@@ -58,7 +58,7 @@ static cl::opt<bool> PGOWarnMisExpect(
     cl::desc("Use this option to turn on/off "
              "warnings about incorrect usage of llvm.expect intrinsics."));
 
-static cl::opt<unsigned> MisExpectTolerance(
+static cl::opt<uint32_t> MisExpectTolerance(
     "misexpect-tolerance", cl::init(0),
     cl::desc("Prevents emiting diagnostics when profile counts are "
              "within N% of the threshold.."));
@@ -72,7 +72,7 @@ bool isMisExpectDiagEnabled(LLVMContext &Ctx) {
 }
 
 uint64_t getMisExpectTolerance(LLVMContext &Ctx) {
-  return std::max(static_cast<uint64_t>(MisExpectTolerance),
+  return std::max(static_cast<uint32_t>(MisExpectTolerance),
                   Ctx.getDiagnosticsMisExpectTolerance());
 }