Address comments by improving comments

Signed-off-by: Artem Gindinson <artem.gindinson@intel.com>

Author: Artem Gindinson

clang/lib/CodeGen/CGLoopInfo.cpp

@@ -476,11 +476,12 @@ EmitIVDepLoopMetadata(LLVMContext &Ctx,
   LoopProperties.push_back(MDNode::get(Ctx, MD));
 }
 
-/// Setting the legacy LLVM IR representation of the ivdep attribute
+/// Setting the legacy LLVM IR representation of the ivdep attribute.
 static void EmitLegacyIVDepLoopMetadata(
     LLVMContext &Ctx, llvm::SmallVectorImpl<llvm::Metadata *> &LoopProperties,
     const LoopAttributes::SYCLIVDepInfo &I) {
-  // Emit "enable" metadata upon the infinite safelen specification
+  // Only emit the "enable" metadata if the safelen is set to 0, implying
+  // infinite safe length.
   if (I.SafeLen == 0) {
     Metadata *EnableMDs[] = {MDString::get(Ctx, "llvm.loop.ivdep.enable")};
     LoopProperties.push_back(MDNode::get(Ctx, EnableMDs));

clang/test/CodeGenSYCL/intel-fpga-ivdep-array.cpp

@@ -186,7 +186,7 @@ int main() {
 // CHECK-DAG: ![[IVDEP_MUL_ARR_VAL]] = !{!"llvm.loop.parallel_access_indices", ![[IDX_GROUP_A_MUL_ARR]], ![[IDX_GROUP_B_MUL_ARR]], i32 5}
 // CHECK-DAG: ![[IVDEP_MUL_ARR_INF]] = !{!"llvm.loop.parallel_access_indices", ![[IDX_GROUP_C_MUL_ARR]], ![[IDX_GROUP_D_MUL_ARR]]}
 
-// Find the single instance of a legacy "IVDep enable" MD node
+// Find the single instance of a legacy "IVDep enable" MD node.
 // CHECK-DAG: ![[IVDEP_LEGACY_ENABLE:[0-9]+]] = !{!"llvm.loop.ivdep.enable"}
 
 /// Global INF safelen and specific array INF safelen

clang/test/CodeGenSYCL/intel-fpga-ivdep-embedded-loops.cpp

@@ -164,7 +164,7 @@ int main() {
   return 0;
 }
 
-// Find the single instance of a legacy "IVDep enable" MD node
+// Find the single instance of a legacy "IVDep enable" MD node.
 // CHECK-DAG: ![[IVDEP_LEGACY_ENABLE:[0-9]+]] = !{!"llvm.loop.ivdep.enable"}
 
 /// Accesses from the inner loop only, various global safelens for the outer and the inner loops.

clang/test/CodeGenSYCL/intel-fpga-ivdep-global.cpp

@@ -94,7 +94,7 @@ int main() {
   return 0;
 }
 
-// Find recurring instances of legacy "IVDep enable/safelen" MD nodes
+// Find recurring instances of legacy "IVDep enable/safelen" MD nodes.
 // CHECK-DAG: ![[IVDEP_LEGACY_ENABLE:[0-9]+]] = !{!"llvm.loop.ivdep.enable"}
 // CHECK-DAG: ![[IVDEP_LEGACY_SAFELEN_5:[0-9]+]] = !{!"llvm.loop.ivdep.safelen", i32 5}