[SandboxVectorizer][NFC] Factor out common parts of SeedCollectorTest setup

It would be nice if gunit allowed custom constructors so all
these fields could be members of SeedCollectorTest, but it doesnt.

Doing this without a macro requires hoops like the abandoned
Sterling-Augustine@a294b83
so a macro seems the least bad solution.

Author: Sterling-Augustine

llvm/unittests/Transforms/Vectorize/SandboxVectorizer/SeedCollectorTest.cpp

@@ -22,7 +22,25 @@
 
 using namespace llvm;
 
-struct SeedBundleTest : public testing::Test {
+// We need several LLVM data structures to collect seeds from llvm-ir, but they
+// have to be constructed as only after parsing the asm string, and most are
+// never referred to again. Constructing them as member variables is awkward,
+// because gUnit doesn't support custom constructors, so we can't pass the asm
+// string as part of test construction. They would have to go in a sub-object
+// created after parsing.
+
+#define createLLVMF(FName, AsmString)                                          \
+  parseIR(C, AsmString);                                                       \
+  Function &LLVMF = *M->getFunction(FName);                                    \
+  DominatorTree DT(LLVMF);                                                     \
+  TargetLibraryInfoImpl TLII;                                                  \
+  TargetLibraryInfo TLI(TLII);                                                 \
+  DataLayout DL(M->getDataLayout());                                           \
+  LoopInfo LI(DT);                                                             \
+  AssumptionCache AC(LLVMF);                                                   \
+  ScalarEvolution SE(LLVMF, TLI, AC, DT, LI);
+
+struct SeedCollectorTest : public testing::Test {
   LLVMContext C;
   std::unique_ptr<Module> M;
 
@@ -49,8 +67,8 @@ class SeedBundleForTest : public sandboxir::SeedBundle {
   }
 };
 
-TEST_F(SeedBundleTest, SeedBundle) {
-  parseIR(C, R"IR(
+TEST_F(SeedCollectorTest, SeedBundle) {
+  createLLVMF("foo", R"IR(
 define void @foo(float %v0, i32 %i0, i16 %i1, i8 %i2) {
 bb:
   %add0 = fadd float %v0, %v0
@@ -64,10 +82,8 @@ define void @foo(float %v0, i32 %i0, i16 %i1, i8 %i2) {
   ret void
 }
 )IR");
-  Function &LLVMF = *M->getFunction("foo");
   sandboxir::Context Ctx(C);
   auto &F = *Ctx.createFunction(&LLVMF);
-  DataLayout DL(M->getDataLayout());
   auto *BB = &*F.begin();
   auto It = BB->begin();
   auto *I0 = &*It++;
@@ -145,8 +161,8 @@ define void @foo(float %v0, i32 %i0, i16 %i1, i8 %i2) {
   EXPECT_EQ(Slice4.size(), 0u);
 }
 
-TEST_F(SeedBundleTest, MemSeedBundle) {
-  parseIR(C, R"IR(
+TEST_F(SeedCollectorTest, MemSeedBundle) {
+  createLLVMF("foo", R"IR(
 define void @foo(ptr %ptrA, float %val, ptr %ptr) {
 bb:
   %gep0 = getelementptr float, ptr %ptr, i32 0
@@ -166,15 +182,6 @@ define void @foo(ptr %ptrA, float %val, ptr %ptr) {
   ret void
 }
 )IR");
-  Function &LLVMF = *M->getFunction("foo");
-
-  DominatorTree DT(LLVMF);
-  TargetLibraryInfoImpl TLII;
-  TargetLibraryInfo TLI(TLII);
-  DataLayout DL(M->getDataLayout());
-  LoopInfo LI(DT);
-  AssumptionCache AC(LLVMF);
-  ScalarEvolution SE(LLVMF, TLI, AC, DT, LI);
 
   sandboxir::Context Ctx(C);
   auto &F = *Ctx.createFunction(&LLVMF);
@@ -206,8 +213,8 @@ define void @foo(ptr %ptrA, float %val, ptr %ptr) {
   EXPECT_THAT(LB, testing::ElementsAre(L0, L1, L2, L3));
 }
 
-TEST_F(SeedBundleTest, Container) {
-  parseIR(C, R"IR(
+TEST_F(SeedCollectorTest, Container) {
+  createLLVMF("foo", R"IR(
 define void @foo(ptr %ptrA, float %val, ptr %ptrB) {
 bb:
   %gepA0 = getelementptr float, ptr %ptrA, i32 0
@@ -221,16 +228,6 @@ define void @foo(ptr %ptrA, float %val, ptr %ptrB) {
   ret void
 }
 )IR");
-  Function &LLVMF = *M->getFunction("foo");
-
-  DominatorTree DT(LLVMF);
-  TargetLibraryInfoImpl TLII;
-  TargetLibraryInfo TLI(TLII);
-  DataLayout DL(M->getDataLayout());
-  LoopInfo LI(DT);
-  AssumptionCache AC(LLVMF);
-  ScalarEvolution SE(LLVMF, TLI, AC, DT, LI);
-
   sandboxir::Context Ctx(C);
   auto &F = *Ctx.createFunction(&LLVMF);
   auto &BB = *F.begin();