aot compiler: Some updates for LLVM 18 (#2981)

Note: This commit includes copy-and-paste from LLVM and thus adds
the LLVM copyright notice.

cf. https://github.com/llvm/llvm-project/commit/0a1aa6cda2758b0926a95f87d39ffefb1cb90200
cf. https://github.com/llvm/llvm-project/commit/a1e9777b760fbd4428073fd7b0fc8bea15bd2183
cf. https://github.com/llvm/llvm-project/commit/56c72c7f339cd6ff780a0d6aa1a0ac8bfc1487aa

core/iwasm/compilation/aot_llvm_extra.cpp

@@ -409,7 +409,10 @@ aot_compress_aot_func_names(AOTCompContext *comp_ctx, uint32 *p_size)
         NameStrs.push_back(str);
     }
 
-    if (collectPGOFuncNameStrings(NameStrs, true, Result)) {
+#if LLVM_VERSION_MAJOR < 18
+#define collectGlobalObjectNameStrings collectPGOFuncNameStrings
+#endif
+    if (collectGlobalObjectNameStrings(NameStrs, true, Result)) {
         aot_set_last_error("collect pgo func name strings failed");
         return NULL;
     }

core/iwasm/compilation/aot_llvm_extra2.cpp

@@ -58,6 +58,7 @@ convert(LLVMRelocMode reloc_mode)
 #endif
 }
 
+#if LLVM_VERSION_MAJOR < 18
 static llvm::CodeGenOpt::Level
 convert(LLVMCodeGenOptLevel opt_level)
 {
@@ -74,6 +75,24 @@ convert(LLVMCodeGenOptLevel opt_level)
     bh_assert(0);
     return llvm::CodeGenOpt::None;
 }
+#else
+static llvm::CodeGenOptLevel
+convert(LLVMCodeGenOptLevel opt_level)
+{
+    switch (opt_level) {
+        case LLVMCodeGenLevelNone:
+            return llvm::CodeGenOptLevel::None;
+        case LLVMCodeGenLevelLess:
+            return llvm::CodeGenOptLevel::Less;
+        case LLVMCodeGenLevelDefault:
+            return llvm::CodeGenOptLevel::Default;
+        case LLVMCodeGenLevelAggressive:
+            return llvm::CodeGenOptLevel::Aggressive;
+    }
+    bh_assert(0);
+    return llvm::CodeGenOptLevel::None;
+}
+#endif
 
 static llvm::Optional<llvm::CodeModel::Model>
 convert(LLVMCodeModel code_model, bool *jit)

core/iwasm/compilation/aot_orc_extra.cpp

@@ -3,6 +3,10 @@
  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  */
 
+// 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 "llvm-c/LLJIT.h"
 #include "llvm-c/Orc.h"
 #include "llvm-c/OrcEE.h"
@@ -44,6 +48,7 @@ class InProgressLookupState;
 class OrcV2CAPIHelper
 {
   public:
+#if LLVM_VERSION_MAJOR < 18
     using PoolEntry = SymbolStringPtr::PoolEntry;
     using PoolEntryPtr = SymbolStringPtr::PoolEntryPtr;
 
@@ -86,6 +91,7 @@ class OrcV2CAPIHelper
         S.S = P;
     }
 
+#endif
     static InProgressLookupState *extractLookupState(LookupState &LS)
     {
         return LS.IPLS.release();
@@ -101,6 +107,20 @@ class OrcV2CAPIHelper
 } // namespace llvm
 
 // ORC.h
+#if LLVM_VERSION_MAJOR >= 18
+inline LLVMOrcSymbolStringPoolEntryRef
+wrap(SymbolStringPoolEntryUnsafe E)
+{
+    return reinterpret_cast<LLVMOrcSymbolStringPoolEntryRef>(E.rawPtr());
+}
+
+inline SymbolStringPoolEntryUnsafe
+unwrap(LLVMOrcSymbolStringPoolEntryRef E)
+{
+    return reinterpret_cast<SymbolStringPoolEntryUnsafe::PoolEntry *>(E);
+}
+#endif
+
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ExecutionSession, LLVMOrcExecutionSessionRef)
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(IRTransformLayer, LLVMOrcIRTransformLayerRef)
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(JITDylib, LLVMOrcJITDylibRef)
@@ -108,8 +128,10 @@ DEFINE_SIMPLE_CONVERSION_FUNCTIONS(JITTargetMachineBuilder,
                                    LLVMOrcJITTargetMachineBuilderRef)
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ObjectTransformLayer,
                                    LLVMOrcObjectTransformLayerRef)
+#if LLVM_VERSION_MAJOR < 18
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(OrcV2CAPIHelper::PoolEntry,
                                    LLVMOrcSymbolStringPoolEntryRef)
+#endif
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ObjectLayer, LLVMOrcObjectLayerRef)
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(SymbolStringPool, LLVMOrcSymbolStringPoolRef)
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ThreadSafeModule, LLVMOrcThreadSafeModuleRef)
@@ -292,8 +314,13 @@ LLVMOrcSymbolStringPoolEntryRef
 LLVMOrcLLLazyJITMangleAndIntern(LLVMOrcLLLazyJITRef J,
                                 const char *UnmangledName)
 {
+#if LLVM_VERSION_MAJOR < 18
     return wrap(OrcV2CAPIHelper::moveFromSymbolStringPtr(
         unwrap(J)->mangleAndIntern(UnmangledName)));
+#else
+    return wrap(SymbolStringPoolEntryUnsafe::take(
+        unwrap(J)->mangleAndIntern(UnmangledName)));
+#endif
 }
 
 LLVMOrcJITDylibRef