[NFC][InstCombine] Fix namespace usage in InstCombine (#161902)

Author: jurahul

llvm/lib/Transforms/InstCombine/InstCombineAtomicRMW.cpp

@@ -15,13 +15,12 @@
 
 using namespace llvm;
 
-namespace {
 /// Return true if and only if the given instruction does not modify the memory
 /// location referenced.  Note that an idemptent atomicrmw may still have
 /// ordering effects on nearby instructions, or be volatile.
 /// TODO: Common w/ the version in AtomicExpandPass, and change the term used.
 /// Idemptotent is confusing in this context.
-bool isIdempotentRMW(AtomicRMWInst& RMWI) {
+static bool isIdempotentRMW(AtomicRMWInst &RMWI) {
   if (auto CF = dyn_cast<ConstantFP>(RMWI.getValOperand()))
     switch(RMWI.getOperation()) {
     case AtomicRMWInst::FAdd: // -0.0
@@ -59,7 +58,7 @@ bool isIdempotentRMW(AtomicRMWInst& RMWI) {
 
 /// Return true if the given instruction always produces a value in memory
 /// equivalent to its value operand.
-bool isSaturating(AtomicRMWInst& RMWI) {
+static bool isSaturating(AtomicRMWInst &RMWI) {
   if (auto CF = dyn_cast<ConstantFP>(RMWI.getValOperand()))
     switch (RMWI.getOperation()) {
     case AtomicRMWInst::FMax:
@@ -98,7 +97,6 @@ bool isSaturating(AtomicRMWInst& RMWI) {
     return C->isMaxValue(false);
   };
 }
-} // namespace
 
 Instruction *InstCombinerImpl::visitAtomicRMWInst(AtomicRMWInst &RMWI) {
 

llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -132,8 +132,6 @@ STATISTIC(NumReassoc  , "Number of reassociations");
 DEBUG_COUNTER(VisitCounter, "instcombine-visit",
               "Controls which instructions are visited");
 
-namespace llvm {
-
 static cl::opt<bool> EnableCodeSinking("instcombine-code-sinking",
                                        cl::desc("Enable code sinking"),
                                        cl::init(true));
@@ -146,7 +144,9 @@ static cl::opt<unsigned>
 MaxArraySize("instcombine-maxarray-size", cl::init(1024),
              cl::desc("Maximum array size considered when doing a combine"));
 
+namespace llvm {
 extern cl::opt<bool> ProfcheckDisableMetadataFixes;
+} // end namespace llvm
 
 // FIXME: Remove this flag when it is no longer necessary to convert
 // llvm.dbg.declare to avoid inaccurate debug info. Setting this to false
@@ -158,8 +158,6 @@ extern cl::opt<bool> ProfcheckDisableMetadataFixes;
 static cl::opt<unsigned> ShouldLowerDbgDeclare("instcombine-lower-dbg-declare",
                                                cl::Hidden, cl::init(true));
 
-} // end namespace llvm
-
 std::optional<Instruction *>
 InstCombiner::targetInstCombineIntrinsic(IntrinsicInst &II) {
   // Handle target specific intrinsics