Caching layout struct types

LdStCombine is a function pass. Previously, the newly-created layout
struct types are searched by invoking Module's getIdentifiedStructTypes(),
so that struct types, created from the previous functions, can be reused
whenever possible.

But getIdentifiedStructTypes() is costly. Thus, there, we caching struct
types in codegencontext for reuse.

(cherry picked from commit de5dc9e)

Author: jgu222

IGC/Compiler/CISACodeGen/MemOpt.cpp

@@ -2573,8 +2573,6 @@ namespace {
         bool getAddressDiffIfConstant(Instruction* I0, Instruction* I1, int64_t& ConstBO);
 
         // Create unique identified struct type
-        SmallVector<StructType*, 16> m_allLayoutStructTypes;
-        void initLayoutStructType(Module* M);
         StructType* getOrCreateUniqueIdentifiedStructType(
             ArrayRef<Type*> EltTys, bool IsSOA, bool IsPacked = true);
 
@@ -2588,7 +2586,6 @@ namespace {
             m_visited.clear();
             m_instOrder.clear();
             m_bundles.clear();
-            m_allLayoutStructTypes.clear();
         }
     };
 }
@@ -2773,8 +2770,6 @@ bool LdStCombine::runOnFunction(Function& F)
     }
     m_F = &F;
 
-    initLayoutStructType(m_F->getParent());
-
     // Initialize symbolic evaluation
     m_symEval.setDataLayout(m_DL);
 
@@ -3397,23 +3392,6 @@ void LdStCombine::mergeConstElements(
     EltVals.insert(EltVals.end(), mergedElts.begin(), mergedElts.end());
 }
 
-// Get all layout struct types created already for different functions in
-// the same module.
-//
-// This is for creating unique struct layout type per module. Layout
-// struct type is identified, but if two identified layout structs are
-// the same layout, they are the same.
-void LdStCombine::initLayoutStructType(Module* M)
-{
-    auto modAllNamedStructTys = M->getIdentifiedStructTypes();
-    for (auto II : modAllNamedStructTys) {
-        StructType* stTy = II;
-        if (isLayoutStructType(stTy)) {
-            m_allLayoutStructTypes.push_back(stTy);
-        }
-    }
-}
-
 // This is to make sure to reuse the layout types. Two identified structs have
 // the same layout if
 //   1. both are SOA or both are AOS; and
@@ -3422,7 +3400,8 @@ void LdStCombine::initLayoutStructType(Module* M)
 StructType* LdStCombine::getOrCreateUniqueIdentifiedStructType(
     ArrayRef<Type*> EltTys, bool IsSOA, bool IsPacked)
 {
-    for (auto II : m_allLayoutStructTypes) {
+    auto& layoutStructTypes = m_CGC->getLayoutStructTypes();
+    for (auto II : layoutStructTypes) {
         StructType* stTy = II;
         if (IsPacked == stTy->isPacked() &&
             IsSOA == isLayoutStructTypeSOA(stTy) &&
@@ -3434,7 +3413,7 @@ StructType* LdStCombine::getOrCreateUniqueIdentifiedStructType(
     StructType* StTy = StructType::create(EltTys,
         IsSOA ? getStructNameForSOALayout() : getStructNameForAOSLayout(),
         IsPacked);
-    m_allLayoutStructTypes.push_back(StTy);
+    layoutStructTypes.push_back(StTy);
     return StTy;
 }
 

IGC/Compiler/CodeGenPublic.h

@@ -849,6 +849,8 @@ namespace IGC
         SafeIntrinsicIDCacheTy m_SafeIntrinsicIDCache;
         /// metadata caching
         UserAddrSpaceMD m_UserAddrSpaceMD;
+        // structType caching : for unique identified struct type
+        llvm::SmallVector<llvm::StructType*, 16> m_allLayoutStructTypes;
         void AddRef();
         void Release();
     };
@@ -1101,6 +1103,10 @@ namespace IGC
             IGC_ASSERT(llvmCtxWrapper);
             return llvmCtxWrapper->m_UserAddrSpaceMD;
         }
+        llvm::SmallVector<llvm::StructType*, 16>& getLayoutStructTypes() {
+            IGC_ASSERT(llvmCtxWrapper);
+            return llvmCtxWrapper->m_allLayoutStructTypes;
+        }
 
         unsigned int GetSIMDInfoOffset(SIMDMode simd, ShaderDispatchMode mode)
         {