[DebugInfo] Simplify DIEInteger::SizeOf().

An AsmPrinter should always be provided to the method because some forms
depend on its parameters. The only place in the codebase which passed
a nullptr value was found in the unit tests, so the patch updates it to
use some dummy AsmPrinter instead.

Differential Revision: https://reviews.llvm.org/D85293

Author: igorkudrin

llvm/lib/CodeGen/AsmPrinter/DIE.cpp

@@ -428,10 +428,10 @@ void DIEInteger::emitValue(const AsmPrinter *Asm, dwarf::Form Form) const {
 /// SizeOf - Determine size of integer value in bytes.
 ///
 unsigned DIEInteger::SizeOf(const AsmPrinter *AP, dwarf::Form Form) const {
-  dwarf::FormParams Params = {0, 0, dwarf::DWARF32};
-  if (AP)
-    Params = {AP->getDwarfVersion(), uint8_t(AP->getPointerSize()),
-              AP->OutStreamer->getContext().getDwarfFormat()};
+  assert(AP && "AsmPrinter is required to set FormParams");
+  dwarf::FormParams Params = {AP->getDwarfVersion(),
+                              uint8_t(AP->getPointerSize()),
+                              AP->OutStreamer->getContext().getDwarfFormat()};
 
   if (Optional<uint8_t> FixedSize = dwarf::getFixedFormByteSize(Form, Params))
     return *FixedSize;

llvm/unittests/CodeGen/DIEHashTest.cpp

@@ -7,12 +7,15 @@
 //===----------------------------------------------------------------------===//
 
 #include "../lib/CodeGen/AsmPrinter/DIEHash.h"
+#include "TestAsmPrinter.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/CodeGen/DIE.h"
 #include "llvm/CodeGen/DwarfStringPoolEntry.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Format.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
 
 using namespace llvm;
@@ -26,13 +29,27 @@ class DIEHashTest : public testing::Test {
 
 private:
   StringMap<DwarfStringPoolEntry> Pool;
+  std::unique_ptr<TestAsmPrinter> TestPrinter;
+
+  void setupTestPrinter() {
+    auto ExpectedTestPrinter = TestAsmPrinter::create(
+        sys::getDefaultTargetTriple(), /*DwarfVersion=*/4, dwarf::DWARF32);
+    ASSERT_THAT_EXPECTED(ExpectedTestPrinter, Succeeded());
+    TestPrinter = std::move(ExpectedTestPrinter.get());
+  }
 
 public:
   DIEString getString(StringRef S) {
     DwarfStringPoolEntry Entry = {nullptr, 1, 1};
     return DIEString(DwarfStringPoolEntryRef(
         *Pool.insert(std::make_pair(S, Entry)).first, Entry.isIndexed()));
   }
+
+  AsmPrinter *getAsmPrinter() {
+    if (!TestPrinter)
+      setupTestPrinter();
+    return TestPrinter ? TestPrinter->getAP() : nullptr;
+  }
 };
 
 TEST_F(DIEHashTest, Data1) {
@@ -644,6 +661,10 @@ TEST_F(DIEHashTest, MemberSdata) {
 // };
 // A a;
 TEST_F(DIEHashTest, MemberBlock) {
+  if (!this->getAsmPrinter())
+    // TODO: Use GTEST_SKIP() when GTest is updated to version 1.10.0
+    return;
+
   DIE &A = *DIE::get(Alloc, dwarf::DW_TAG_structure_type);
   DIEInteger One(1);
   DIEString AStr = getString("A");
@@ -692,7 +713,7 @@ TEST_F(DIEHashTest, MemberBlock) {
 
   A.addChild(std::move(PI));
 
-  uint64_t MD5Res = DIEHash().computeTypeSignature(A);
+  uint64_t MD5Res = DIEHash(this->getAsmPrinter()).computeTypeSignature(A);
   ASSERT_EQ(0x493af53ad3d3f651ULL, MD5Res);
 }
 }