[llvm] [nfc][InstrProfiling]Compute a boolean state as a constant and use it everywhere (PR #83756)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-pgo

Author: Mingming Liu (minglotus-6)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/83756.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp (+24-24) 


``````````diff
diff --git a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
index dbd44bd36e1148..d5d55dec6382fb 100644
--- a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -168,13 +168,33 @@ cl::opt<bool> SkipRetExitBlock(
 
 using LoadStorePair = std::pair<Instruction *, Instruction *>;
 
+static uint64_t getIntModuleFlagOrZero(const Module &M, StringRef Flag) {
+  auto *MD = dyn_cast_or_null<ConstantAsMetadata>(M.getModuleFlag(Flag));
+  if (!MD)
+    return 0;
+
+  // If the flag is a ConstantAsMetadata, it should be an integer representable
+  // in 64-bits.
+  return cast<ConstantInt>(MD->getValue())->getZExtValue();
+}
+
+static bool enablesValueProfiling(const Module &M) {
+  return isIRPGOFlagSet(&M) ||
+         getIntModuleFlagOrZero(M, "EnableValueProfiling") != 0;
+}
+
+// Conservatively returns true if value profiling is enabled.
+static bool profDataReferencedByCode(const Module &M) {
+  return enablesValueProfiling(M);
+}
+
 class InstrLowerer final {
 public:
   InstrLowerer(Module &M, const InstrProfOptions &Options,
                std::function<const TargetLibraryInfo &(Function &F)> GetTLI,
                bool IsCS)
       : M(M), Options(Options), TT(Triple(M.getTargetTriple())), IsCS(IsCS),
-        GetTLI(GetTLI) {}
+        GetTLI(GetTLI), DataReferencedByCode(profDataReferencedByCode(M)) {}
 
   bool lower();
 
@@ -186,6 +206,8 @@ class InstrLowerer final {
   const bool IsCS;
 
   std::function<const TargetLibraryInfo &(Function &F)> GetTLI;
+
+  const bool DataReferencedByCode;
   struct PerFunctionProfileData {
     uint32_t NumValueSites[IPVK_Last + 1] = {};
     GlobalVariable *RegionCounters = nullptr;
@@ -1057,26 +1079,6 @@ static std::string getVarName(InstrProfInstBase *Inc, StringRef Prefix,
   return (Prefix + Name + "." + Twine(FuncHash)).str();
 }
 
-static uint64_t getIntModuleFlagOrZero(const Module &M, StringRef Flag) {
-  auto *MD = dyn_cast_or_null<ConstantAsMetadata>(M.getModuleFlag(Flag));
-  if (!MD)
-    return 0;
-
-  // If the flag is a ConstantAsMetadata, it should be an integer representable
-  // in 64-bits.
-  return cast<ConstantInt>(MD->getValue())->getZExtValue();
-}
-
-static bool enablesValueProfiling(const Module &M) {
-  return isIRPGOFlagSet(&M) ||
-         getIntModuleFlagOrZero(M, "EnableValueProfiling") != 0;
-}
-
-// Conservatively returns true if data variables may be referenced by code.
-static bool profDataReferencedByCode(const Module &M) {
-  return enablesValueProfiling(M);
-}
-
 static inline bool shouldRecordFunctionAddr(Function *F) {
   // Only record function addresses if IR PGO is enabled or if clang value
   // profiling is enabled. Recording function addresses greatly increases object
@@ -1192,7 +1194,6 @@ static bool needsRuntimeRegistrationOfSectionRange(const Triple &TT) {
 
 void InstrLowerer::maybeSetComdat(GlobalVariable *GV, Function *Fn,
                                   StringRef VarName) {
-  bool DataReferencedByCode = profDataReferencedByCode(M);
   bool NeedComdat = needsComdatForCounter(*Fn, M);
   bool UseComdat = (NeedComdat || TT.isOSBinFormatELF());
 
@@ -1418,7 +1419,6 @@ void InstrLowerer::createDataVariable(InstrProfCntrInstBase *Inc) {
     Visibility = GlobalValue::DefaultVisibility;
   }
 
-  bool DataReferencedByCode = profDataReferencedByCode(M);
   bool NeedComdat = needsComdatForCounter(*Fn, M);
   bool Renamed;
 
@@ -1719,7 +1719,7 @@ void InstrLowerer::emitUses() {
   // and ensure this GC property as well. Otherwise, we have to conservatively
   // make all of the sections retained by the linker.
   if (TT.isOSBinFormatELF() || TT.isOSBinFormatMachO() ||
-      (TT.isOSBinFormatCOFF() && !profDataReferencedByCode(M)))
+      (TT.isOSBinFormatCOFF() && !DataReferencedByCode))
     appendToCompilerUsed(M, CompilerUsedVars);
   else
     appendToUsed(M, CompilerUsedVars);

``````````

</details>


https://github.com/llvm/llvm-project/pull/83756