Make Function::getInstructionCount const

Summary: Function::getInstructionCount can be const.

Reviewers: davidxl, paquette

Reviewed By: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53378

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344754 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/IR/Function.h

@@ -158,7 +158,7 @@ class Function : public GlobalObject, public ilist_node<Function> {
   /// Returns the number of non-debug IR instructions in this function.
   /// This is equivalent to the sum of the sizes of each basic block contained
   /// within this function.
-  unsigned getInstructionCount();
+  unsigned getInstructionCount() const;
 
   /// Returns the FunctionType for me.
   FunctionType *getFunctionType() const {

lib/IR/Function.cpp

@@ -195,9 +195,9 @@ LLVMContext &Function::getContext() const {
   return getType()->getContext();
 }
 
-unsigned Function::getInstructionCount() {
+unsigned Function::getInstructionCount() const {
   unsigned NumInstrs = 0;
-  for (BasicBlock &BB : BasicBlocks)
+  for (const BasicBlock &BB : BasicBlocks)
     NumInstrs += std::distance(BB.instructionsWithoutDebug().begin(),
                                BB.instructionsWithoutDebug().end());
   return NumInstrs;