[VPlan] Add VPlanTestBase.h with helper class to build VPlan for tests.

[dcaballe]

Good idea! Thanks! LGTM. Just some minor comments.

unittests/Transforms/Vectorize/VPlanHCFGTest.cpp

93

Shouldn't we keep VPlanHCFGTest name? Or, is this renaming needed?

unittests/Transforms/Vectorize/VPlanTestBase.h

9

Add small comment about the purpose of the file?

46

I had to differentiate between building 'plain' CFG and building H-CFG for testing in D48818. It would be great I you could align this code a bit with those needs. I'll introduce the necessary changes once we have this code in.

unittests/Transforms/Vectorize/VPlanHCFGTest.cpp

 //===- llvm/unittest/Transforms/Vectorize/VPlanHCFGTest.cpp ---------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "../lib/Transforms/Vectorize/VPlan.h"
-#include "../lib/Transforms/Vectorize/VPlanHCFGBuilder.h"
 #include "../lib/Transforms/Vectorize/VPlanHCFGTransforms.h"
-#include "llvm/AsmParser/Parser.h"
-#include "llvm/IR/Dominators.h"
+#include "VPlanTestBase.h"
 #include "gtest/gtest.h"
 
 namespace llvm {
 namespace {
 
-class VPlanHCFGTest : public testing::Test {
-protected:
-  std::unique_ptr<DominatorTree> DT;
-  std::unique_ptr<LoopInfo> LI;
-
-  VPlanHCFGTest() {}
-
-  VPlanPtr doBuildPlan(BasicBlock *LoopHeader) {
-    DT.reset(new DominatorTree(*LoopHeader->getParent()));
-    LI.reset(new LoopInfo(*DT));
-
-    auto Plan = llvm::make_unique<VPlan>();
-    VPlanHCFGBuilder HCFGBuilder(LI->getLoopFor(LoopHeader), LI.get());
-    HCFGBuilder.buildHierarchicalCFG(*Plan.get());
-    return Plan;
-  }
-};
-
-TEST_F(VPlanHCFGTest, testBuildHCFGInnerLoop) {
-  LLVMContext Ctx;
+TEST_F(VPlanTestBase, testBuildHCFGInnerLoop) {
   const char *ModuleString =
       "define void @f(i32* %A, i64 %N) {\n"
       "entry:\n"
       "  br label %for.body\n"
       "for.body:\n"
       "  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]\n"
       "  %arr.idx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv\n"
       "  %l1 = load i32, i32* %arr.idx, align 4\n"
       "  %res = add i32 %l1, 10\n"
       "  store i32 %res, i32* %arr.idx, align 4\n"
       "  %indvars.iv.next = add i64 %indvars.iv, 1\n"
       "  %exitcond = icmp ne i64 %indvars.iv.next, %N\n"
       "  br i1 %exitcond, label %for.body, label %for.end\n"
       "for.end:\n"
       "  ret void\n"
       "}\n";
 
-  SMDiagnostic Err;
-  std::unique_ptr<Module> M = parseAssemblyString(ModuleString, Err, Ctx);
+  Module &M = parseModule(ModuleString);
 
-  Function *F = M->getFunction("f");
+  Function *F = M.getFunction("f");
   BasicBlock *LoopHeader = F->getEntryBlock().getSingleSuccessor();
   auto Plan = doBuildPlan(LoopHeader);
 
   VPBlockBase *Entry = Plan->getEntry()->getEntryBasicBlock();
   EXPECT_NE(nullptr, Entry->getSingleSuccessor());
   EXPECT_EQ(0u, Entry->getNumPredecessors());
   EXPECT_EQ(1u, Entry->getNumSuccessors());
 
TEST_F(VPlanTestBase, testBuildHCFGInnerLoop) {
   EXPECT_EQ(IndvarAdd, ICmp->getOperand(0));
 
   LoopVectorizationLegality::InductionList Inductions;
   SmallPtrSet<Instruction *, 1> DeadInstructions;
   VPlanHCFGTransforms::VPInstructionsToVPRecipes(Plan, &Inductions,
                                                  DeadInstructions);
 }
 
-TEST_F(VPlanHCFGTest, testVPInstructionToVPRecipesInner) {
-  LLVMContext Ctx;
+TEST_F(VPlanTestBase, testVPInstructionToVPRecipesInner) {
   const char *ModuleString =
       "define void @f(i32* %A, i64 %N) {\n"
       "entry:\n"
       "  br label %for.body\n"
       "for.body:\n"
       "  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]\n"
       "  %arr.idx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv\n"
       "  %l1 = load i32, i32* %arr.idx, align 4\n"
       "  %res = add i32 %l1, 10\n"
       "  store i32 %res, i32* %arr.idx, align 4\n"
       "  %indvars.iv.next = add i64 %indvars.iv, 1\n"
       "  %exitcond = icmp ne i64 %indvars.iv.next, %N\n"
       "  br i1 %exitcond, label %for.body, label %for.end\n"
       "for.end:\n"
       "  ret void\n"
       "}\n";
 
-  SMDiagnostic Err;
-  std::unique_ptr<Module> M = parseAssemblyString(ModuleString, Err, Ctx);
+  Module &M = parseModule(ModuleString);
 
-  Function *F = M->getFunction("f");
+  Function *F = M.getFunction("f");
   BasicBlock *LoopHeader = F->getEntryBlock().getSingleSuccessor();
   auto Plan = doBuildPlan(LoopHeader);
 
   LoopVectorizationLegality::InductionList Inductions;
   SmallPtrSet<Instruction *, 1> DeadInstructions;
   VPlanHCFGTransforms::VPInstructionsToVPRecipes(Plan, &Inductions,
                                                  DeadInstructions);
 

unittests/Transforms/Vectorize/VPlanTestBase.h

+//===- llvm/unittest/Transforms/Vectorize/VPlanTestBase.h -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_UNITTESTS_TRANSFORMS_VECTORIZE_VPLANTESTBASE_H
+#define LLVM_UNITTESTS_TRANSFORMS_VECTORIZE_VPLANTESTBASE_H
+
+#include "../lib/Transforms/Vectorize/VPlan.h"
+#include "../lib/Transforms/Vectorize/VPlanHCFGBuilder.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/Support/SourceMgr.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+
+/// Helper class to create a module from an assembly string and create a
+/// VPlan.
+class VPlanTestBase : public testing::Test {
+protected:
+  std::unique_ptr<DominatorTree> DT;
+  std::unique_ptr<LoopInfo> LI;
+  std::unique_ptr<Module> M;
+  LLVMContext *Ctx;
+
+  VPlanTestBase() : Ctx(new LLVMContext) {}
+  ~VPlanTestBase() {
+    LI.release();
+    DT.release();
+    M.release();
+    delete Ctx;
+  }
+
+  Module &parseModule(const char *ModuleString) {
+    SMDiagnostic Err;
+    M = parseAssemblyString(ModuleString, Err, *Ctx);
+    return *M;
+  }
+
+  VPlanPtr doBuildPlan(BasicBlock *LoopHeader) {
+    DT.reset(new DominatorTree(*LoopHeader->getParent()));
+    LI.reset(new LoopInfo(*DT));
+
+    auto Plan = llvm::make_unique<VPlan>();
+    VPlanHCFGBuilder HCFGBuilder(LI->getLoopFor(LoopHeader), LI.get());
+    HCFGBuilder.buildHierarchicalCFG(*Plan.get());
+    return Plan;
+  }
+};
+
+} // namespace llvm
+
+#endif // LLVM_UNITTESTS_TRANSFORMS_VECTORIZE_VPLANTESTBASE_H