Fix memory leaks in addCapability and addConditionalCapability (#3403)

Compiling with `-fsanitize=address` uncovered 2 memory leaks related to
the use of raw pointers in `addCapability` and
`addConditionalCapability`.

Instead of manually handling memory, use `std::unique_ptr` to track the
ownership of the pointed object and free the memory for us.

Author: jmmartinez

lib/SPIRV/libSPIRV/SPIRVFnVar.cpp

@@ -169,7 +169,7 @@ bool specializeFnVariants(SPIRVModule *BM, std::string &ErrMsg) {
   for (const auto &CondCap : BM->getConditionalCapabilities()) {
     const SPIRVId Condition = CondCap.first.first;
     const Capability Cap = CondCap.first.second;
-    const SPIRVConditionalCapabilityINTEL *Entry = CondCap.second;
+    const SPIRVConditionalCapabilityINTEL *Entry = CondCap.second.get();
     bool ShouldKeep = false;
     if (!evaluateConstant(BM, Entry->getCondition(), ShouldKeep, ErrMsg)) {
       return false;

lib/SPIRV/libSPIRV/SPIRVModule.cpp

@@ -665,12 +665,6 @@ SPIRVModuleImpl::~SPIRVModuleImpl() {
   for (auto I : IdEntryMap)
     delete I.second;
 
-  for (auto C : CapMap)
-    delete C.second;
-
-  for (auto C : ConditionalCapMap)
-    delete C.second;
-
   for (auto *M : ModuleProcessedVec)
     delete M;
 }
@@ -789,10 +783,12 @@ void SPIRVModuleImpl::addCapability(SPIRVCapabilityKind Cap) {
   addCapabilities(SPIRV::getCapability(Cap));
   SPIRVDBG(spvdbgs() << "addCapability: " << SPIRVCapabilityNameMap::map(Cap)
                      << '\n');
-  if (hasCapability(Cap))
+
+  auto [It, Inserted] = CapMap.try_emplace(Cap);
+  if (!Inserted)
     return;
 
-  auto *CapObj = new SPIRVCapability(this, Cap);
+  auto CapObj = std::make_unique<SPIRVCapability>(this, Cap);
   if (AutoAddExtensions) {
     // While we are reading existing SPIR-V we need to read it as-is and don't
     // add required extensions for each entry automatically
@@ -801,15 +797,16 @@ void SPIRVModuleImpl::addCapability(SPIRVCapabilityKind Cap) {
       addExtension(Ext.value());
   }
 
-  CapMap.insert(std::make_pair(Cap, CapObj));
+  It->second = std::move(CapObj);
 }
 
 void SPIRVModuleImpl::addCapabilityInternal(SPIRVCapabilityKind Cap) {
   if (AutoAddCapability) {
-    if (hasCapability(Cap))
+    auto [It, Inserted] = CapMap.try_emplace(Cap);
+    if (!Inserted)
       return;
 
-    CapMap.insert(std::make_pair(Cap, new SPIRVCapability(this, Cap)));
+    It->second = std::make_unique<SPIRVCapability>(this, Cap);
   }
 }
 
@@ -818,18 +815,19 @@ void SPIRVModuleImpl::addConditionalCapability(SPIRVId Condition,
   SPIRVDBG(spvdbgs() << "addConditionalCapability: "
                      << SPIRVCapabilityNameMap::map(Cap)
                      << ", condition: " << Condition << '\n');
-  if (ConditionalCapMap.find(std::make_pair(Condition, Cap)) !=
-      ConditionalCapMap.end()) {
+  auto Key = std::make_pair(Condition, Cap);
+  auto [It, Inserted] = ConditionalCapMap.try_emplace(Key);
+  if (!Inserted) {
     return;
   }
 
-  auto *CapObj = new SPIRVConditionalCapabilityINTEL(this, Condition, Cap);
+  auto CapObj =
+      std::make_unique<SPIRVConditionalCapabilityINTEL>(this, Condition, Cap);
   if (AutoAddExtensions) {
     assert(false && "Auto adding conditional extensions is not supported.");
   }
 
-  ConditionalCapMap.insert(
-      std::make_pair(std::make_pair(Condition, Cap), CapObj));
+  It->second = std::move(CapObj);
 }
 
 void SPIRVModuleImpl::eraseConditionalCapability(SPIRVId Condition,

lib/SPIRV/libSPIRV/SPIRVModule.h

@@ -109,9 +109,10 @@ struct SPIRVTypeImageDescriptor;
 
 class SPIRVModule {
 public:
-  typedef std::map<SPIRVCapabilityKind, SPIRVCapability *> SPIRVCapMap;
+  typedef std::map<SPIRVCapabilityKind, std::unique_ptr<SPIRVCapability>>
+      SPIRVCapMap;
   typedef std::map<std::pair<SPIRVId, SPIRVCapabilityKind>,
-                   SPIRVConditionalCapabilityINTEL *>
+                   std::unique_ptr<SPIRVConditionalCapabilityINTEL>>
       SPIRVConditionalCapMap;
   typedef std::vector<SPIRVConditionalEntryPointINTEL *>
       SPIRVConditionalEntryPointVec;