[llvm] [DirectX] initialize registers properties by calling addRegisterClass and computeRegisterProperties (PR #128818)

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,65 @@
+//===- llvm/unittests/Target/DirectX/RegisterCostTests.cpp ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "DirectXInstrInfo.h"
+#include "DirectXTargetLowering.h"
+#include "DirectXTargetMachine.h"
+#include "TargetInfo/DirectXTargetInfo.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace llvm::dxil;
+
+namespace {
+class RegisterCostTests : public testing::Test {
+protected:
+  DirectXInstrInfo DXInstInfo;
+  DirectXRegisterInfo RI;
+  DirectXTargetLowering *DL;
+
+  virtual void SetUp() {
+    LLVMInitializeDirectXTargetMC();
+    Target T = getTheDirectXTarget();
+    RegisterTargetMachine<DirectXTargetMachine> X(T);
+    Triple TT("dxil-pc-shadermodel6.3-library");
+    StringRef CPU = "";
+    StringRef FS = "";
+    DirectXTargetMachine TM(T, TT, CPU, FS, TargetOptions(), Reloc::Static,
+                            CodeModel::Small, CodeGenOptLevel::Default, false);
+    LLVMContext Context;
+    Function *F =
+        Function::Create(FunctionType::get(Type::getVoidTy(Context), false),
+                         Function::ExternalLinkage, 0);
+    DL = new DirectXTargetLowering(TM, *TM.getSubtargetImpl(*F));
+    delete F;
+  }
+  virtual void TearDown() { delete DL; }
+};
+
+TEST_F(RegisterCostTests, TestRepRegClassForVTSet) {
+  const TargetRegisterClass *RC = DL->getRepRegClassFor(MVT::i32);
+  EXPECT_EQ(&dxil::DXILClassRegClass, RC);
+}
+
+TEST_F(RegisterCostTests, TestTrivialCopyCostGetter) {
+
+  const TargetRegisterClass *RC = DXInstInfo.getRegisterInfo().getRegClass(0);
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farzonl wrote:

`DirectXTargetLowering` does not expose `DirectXRegisterInfo` so just testing it seperately to confirm we can fetch costing data off of it.

https://github.com/llvm/llvm-project/pull/128818