From 84aa5e555ff1b51ffd4ca3acc1c04505aa3f7b96 Mon Sep 17 00:00:00 2001
From: Eli Bendersky <eliben@google.com>
Date: Wed, 26 Mar 2014 20:41:15 +0000
Subject: [PATCH] Fix problem with r204836

In CallInst, op_end() points at the callee, which we don't want to iterate over
when just iterating over arguments. Now take this into account when returning
a iterator_range from arg_operands. Similar reasoning for InvokeInst.

Also adds a unit test to verify this actually works as expected.

llvm-svn: 204851
---
 llvm/include/llvm/IR/Instructions.h    | 10 ++++++----
 llvm/unittests/IR/InstructionsTest.cpp | 26 ++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/llvm/include/llvm/IR/Instructions.h b/llvm/include/llvm/IR/Instructions.h
index e1dd34568123..06d7287ea164 100644
--- a/llvm/include/llvm/IR/Instructions.h
+++ b/llvm/include/llvm/IR/Instructions.h
@@ -1297,12 +1297,14 @@ public:
 
   /// arg_operands - iteration adapter for range-for loops.
   iterator_range<op_iterator> arg_operands() {
-    return iterator_range<op_iterator>(op_begin(), op_end());
+    // The last operand in the op list is the callee - it's not one of the args
+    // so we don't want to iterate over it.
+    return iterator_range<op_iterator>(op_begin(), op_end() - 1);
   }
 
   /// arg_operands - iteration adapter for range-for loops.
   iterator_range<const_op_iterator> arg_operands() const {
-    return iterator_range<const_op_iterator>(op_begin(), op_end());
+    return iterator_range<const_op_iterator>(op_begin(), op_end() - 1);
   }
 
   /// \brief Wrappers for getting the \c Use of a call argument.
@@ -2954,12 +2956,12 @@ public:
 
   /// arg_operands - iteration adapter for range-for loops.
   iterator_range<op_iterator> arg_operands() {
-    return iterator_range<op_iterator>(op_begin(), op_end());
+    return iterator_range<op_iterator>(op_begin(), op_end() - 3);
   }
 
   /// arg_operands - iteration adapter for range-for loops.
   iterator_range<const_op_iterator> arg_operands() const {
-    return iterator_range<const_op_iterator>(op_begin(), op_end());
+    return iterator_range<const_op_iterator>(op_begin(), op_end() - 3);
   }
 
   /// \brief Wrappers for getting the \c Use of a invoke argument.
diff --git a/llvm/unittests/IR/InstructionsTest.cpp b/llvm/unittests/IR/InstructionsTest.cpp
index 962c07eea149..94065289e2ea 100644
--- a/llvm/unittests/IR/InstructionsTest.cpp
+++ b/llvm/unittests/IR/InstructionsTest.cpp
@@ -14,11 +14,14 @@
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
 #include "gtest/gtest.h"
+#include <memory>
 
 namespace llvm {
 namespace {
@@ -47,6 +50,29 @@ TEST(InstructionsTest, ReturnInst) {
   delete r1;
 }
 
+TEST(InstructionsTest, CallInst) {
+  LLVMContext &C(getGlobalContext());
+  std::unique_ptr<Module> M(new Module("MyModule", C));
+
+  Type *ArgTypes[] = {Type::getInt8Ty(C), Type::getInt32Ty(C),
+                      Type::getInt64Ty(C)};
+  FunctionType *FTy = FunctionType::get(Type::getVoidTy(C), ArgTypes, false);
+  Function *F = Function::Create(FTy, Function::ExternalLinkage, "", M.get());
+
+  Value *Args[] = {ConstantInt::get(Type::getInt8Ty(C), 20),
+                   ConstantInt::get(Type::getInt32Ty(C), 9999),
+                   ConstantInt::get(Type::getInt64Ty(C), 42)};
+  CallInst *Call = CallInst::Create(F, Args);
+
+  // Make sure iteration over a call's arguments works as expected.
+  unsigned Idx = 0;
+  for (Value *Arg : Call->arg_operands()) {
+    EXPECT_EQ(ArgTypes[Idx], Arg->getType());
+    EXPECT_EQ(Call->getArgOperand(Idx)->getType(), Arg->getType());
+    Idx++;
+  }
+}
+
 TEST(InstructionsTest, BranchInst) {
   LLVMContext &C(getGlobalContext());